CA2185226A1

CA2185226A1 - Pressure sensitive adhesive(s) and article(s)

Info

Publication number: CA2185226A1
Application number: CA002185226A
Authority: CA
Inventors: Mary L. Brown; Cheryl L. Moore; Donald R. Battles; Richard J. Goetz
Original assignee: Individual
Current assignee: 3M Co
Priority date: 1994-04-04
Filing date: 1995-02-24
Publication date: 1995-10-12
Also published as: EP0754213B1; JPH09511538A; DE69502489D1; AU1930195A; US5641567A; FI963968A; US5512612A; CN1145087A; FI963968A0; WO1995027016A1; DE69502489T2; BR9507271A; EP0754213A1; HK1011147A1; CN1094500C

Abstract

A pressure sensitive adhesive that employs a water-dispersible polymer is provided. In one embodiment of the invention the adhesive comprises microparticles and the water-dispersible component. In another embodiment the adhesive comprises a novel water-dispersible polymer that contains a plurality of poly(alkoxyalkyl) acrylate units as a major component. This polymer may be used as the water-dispersible component. The pressure sensitive adhesive may be provided as a tape and used with labels for containers, sterilization indicator tapes and labels, closure systems for envelopes, surgical wrappers, and mammalian body coverings. It may also be used in the preparation of paper web splices. In one embodiment of the invention the tape is repulpable. In another embodiment it is launderable.

Description

2t 85226 PRESSI~RE Sl~NSITrVE AD~IESIVE(S) AND ARTICIE(S) S
Field of the In~entior~
This invention relates to pressure sensitive adhesives and articles made therefrom.
10 R~rk~ro~ d o~ tbe Tnvention Pressure sensitive adhesives (PSAs) have gained ~vide spread accept~ce in many ~ ;.- These adhesives are I~ by being normally tacky at room ~ r (e.g., 20C) and forming a bond to a surface by tAe application of, at most, very light finger pressure. They possess a balance of 15 ~;~u~hl~ic and elastic properties which result in a fou}-fold balance of adhesion, cohesion, ~ L~l,in~ and elasticity. They have sufficient col~c~ and elasticity so that they can be handled and removed from surfaces without leaving a residue even though they are tacky. PSAs do not embrace ~J~ C merely because they are sticky or adhere to a surface.
~ lu~iclc-containing PSAs represent one category of PSAs. This category of PSAs contains a plurality of l,.;~,up~ l~ which may or may not be inherently pressure sensitive and may or may not be hollow. r ' u~ i.h cont~ining PSAs may also include a binder to assist im securing the particles toa substrate. The binder may be inherently pressure sensitive if desired.
25 Examples of these PSAs are disclosed in the art. For example, see U.S.
3,857,731 (Merrill et al), U.S. 4,656,218 (Kinoshita), U.S. 4,735,837 (Miyasaka et al), U.S. 4,855,170 (Darvall et al), U.S. 4,994,322 (Delgado et al), U.S. 5,118,750 (Silver et al), and WO 93/02855 (Mallya et al). The adhesives disclosed in these references are not water-30 ~ r~r~ihl~ They ~ ' and form tacky globules when attempts are made to repulp them. The globules, commonly referred to as "stickies" in the WO 95/2~016 PCT/IJS95/02295 art, plug screens used in the repulping process and lead to increased ".~.,..r . ~ time and expense. Additionally, any globules that are not removed by screening adversely affect the quality of the paper product resultingfrom such recycling efforts. As a result a need exists for a water-dispersible S pressure sensitive .,.i~luy~Liclc adhesive that can be readily repulped.
Surnmar~ of the In~ention The present invention overcomes the d;~. g of the prior art. In one aspect of the invention it provides a normally tacky pressure sensitive 10 adhesive ~ made up of a blend of:
A) a polymeric, solvent insoluble but solvent dispersible u~ L;~.lC ~ , ', and B) a water-dispersible polymeric: .
The l~ ,u~.~Liclc component comprises from 0.1 to 99.9 parts by weight of the 15 adhesive ~ The water-dispersible component c~ ,ly comprises from 99.9 to 0.1 parts by weight of the adhesive ~
In another aspect of the invention there is provided a water-dispersible pressure sensitive adhesive .~ " that comprises the product of the emulsion poly,.._ i~Liu-, product of A) from about 50 to 98 parts by weight, preferably from about 80 to 95 parts by weight, of a poly(alkoxyalkyl) acrylate; and B) from about 50 to 2 parts by weight, preferably from about 20 to 5 parts by weight, of a carboxylic acid.
25 These polymers, which contain primarily poly(alkoxyalkyl) acrylate units are pressure sensitive in and of themselves.
The adhesive C~ u~iLiull of the invention is preferably water-r,~ihlP It has improved ~. . r~" " ~ ~ in one or more of tack, adhesion, andhumidity resistance when compared to the c~ , of the prior art. It may 30 be provided either in bulk form or as a PSA sheet of any desired width, that is as a narrow strip or a tape or as a wide film. In elther case, the pressure

-2-2t 85226 WO 95/27016 PCTiU595/02295 sensitive sheet compnses a thin layer (typically less than 125 ~L thick.
Additionally, the adhesive layer may be provided on one or more opposed surfaces of a flexible support. If the adhesive layer is strippably bonded to the support, the resulting product is an adhesive transfer tape. If the adhesive is 5 essentially p. . ,.,~ bonded to the support, the support is referred to herein as a backing.
The adhesive film of the present invention is useful in a variety of c~ ;....c For example, it can be used in the ~ of repulpable paper splices (both permanent and temporary). Additionally, such adhesives can 10 be used with labels for containers, '1 ' indicator tapes and labels, closure systems for containers such as envelopes, closure systems for surgical wrappers, and m-Ar~m~ body coverings (e.g., surgical gowns, sheets, drapes and the like). Other uses for the adhesive and tape of the imvention will be apparent to those skilled in the art as a result of this disclosure.
As used throughout this ~ ri Al;nll, the following terms have the following meanings:
~Water-dispersible" means that the particular material is capable of passing either the TAPPI test UM-213 or the T ' ' ~ Test each of which is described in more detail below.
"Blend" means to a physical ~ ' of the ~"~Li~l~s and the water-dispersible polymeric . L ' The ~ , are not covalently bonded to one another although they may be associated via hydrogen bonding.
' ~ Descr;ntion The ~i. ~ ;rlt Com~nnPr~
The ~ U~Li._l~ component useful in the invention is comprised of polymeric, ~plA~ mtrir~ solvent insoluble but solvent dispersible v~)~uLi~
These spheres may be inherently pressure sensitive if desired, although they ne~d not be so. Additionally, a crosslinker may be added if desired. As 30 l~ ur_~Lul~d, the l~ s are generally spheroidal in shape. They typically have an average diameter in ~h range of from I to 300 (preferably WO 9~/2701G I ~ 9 from 1 to 50) 1~. The ~ UUdlLiCl~,~ used in the invention may be solid or hollow. Hollow ~ lU~Liclc~ may contain more than one void. Typically, the hollow or void portion of the n,i,,-ul ~Li~l~s is less than lO0 ~m in average diameter.
The ~ lu~allicl~s may be prepared by various; ~ processes.
For example the l~ up~lid.,~ may be obtained via suspension ~ul~
such as the following "two-step" i ' ~ pol~ iul~ process comprising the steps of:
a) forming (i) forming a water-in-oil emulsion by mixing an aqueous solution of polar monomer(s) with oil phase monomer(s)l the oil phase monomer(s) being selected from alkyl (meth)acrylate esters and vinyl esters; and (ii) forming a water-in-oil-in-water emulsion by dispersing the water-in-oil emulsion into an aqueous phase; and b) initiating pol~ll.~li~liul., preferably by application of heat ûr radiation.
In this process, the first step preferably involves forming a water-iD-oil emulsion of an aqueous solution of monomer(s) (at least some of which is a 20 polar monomer) in an oil phase monomer, i.e., at least one (meth)acrylate ûr vinyl ester monomer, with optiûnal free radically reactive l.~.l.ul l.ilic oligûmers and/or polymers, using an emulsifier having a low l,~.l.u~l,ili~,-lipophilic balance (HLB) value. Suitable emulsifiers are those having an ~ILB value below about 7, preferably in the range of about 2 to about 7. Examples of such 25 emulsifiers include sorbitan ' , sorbitan trioleate, and t:LIlu~
oleyl alcohol such as Brijn' 93, available from Atlas Chemical Industries, Inc.
In the first phase of t he first step, oil phase monomer~s), emulsifier, a free radical initiator, and, optionally, free radically reactive hydrophilic oligomer and/or polymer, and, 30 optionally, a ~., " 1-in~ monomer or monomers as defined below are combined, and an aqueous solution of all or a portion of the polar monomer(s) is agitated and WO95/27016 1~,I/IJ., _."`?'~qS
poured into the oil phase mixture to form a water-in-oil emulsion. The free radically reactive hydrophilic oligomer and/or polymer, may be added to either the oil phase or the water phase. A thickening agent, e.g., methyl cellulose may also be included in the aqueous phase of the water-in-oil emulsion. In the second phase S of the first step, a water-in-oil-in-water emulsion is formed by dispersing the water-in-oil emulsion of the first step into an aqueous phase containing an emulsifier having an HLB value above about 6. The aqueous phase may also contain any portion of the polar monomer(s) which was not added in step one.
~xamples of such emulsifiers mclude eLIlu~y' ' sorbitan ~ Lhv~0 lauryl alcohol; and alkyl sulfates. In both steps, when an emulsifier is utilized, its should be greater than its critical micelle ~ which is herein defined as the minimum cnr.._. ~,,l;..., of emulsifler necessary for the formation of micelles, i.e., ' U~,U~;C . ~ r~ of emulsifier molecules.
Critical micelle ~ .,l;..., is slightly different for each emulsifier, usable 15 cl~n~Pn~r~rinn~ ranging from about 1.0 x 104 to about 3.0 molesAiter. Additional detail concerning the l~ c ~, - A~ of water-in-oil-in-water emulsions, i.e., multiple emulsions, may be found in various literature references, e.g., S ~ Sys~mc Their ('hPmic~ry. ph~rm-A~y. & E~ir~ln~y, (D. Attwood and A. T. Florence, Chapman & Hall Limited, New York, 1983). If the water-in-oil-in-water emulsion 20 is stable, then hollow or multi-void ul~LiCI~ will be formed.
The second, or final process step of this method involves the application of heat or radiation to initiate pùl~ ~Liull of the monomers. Useful imitiators are those which are normally suitable for free radical pul~ of acrylate or vinyl ester monomers and which are oil soluble and of very low solubility in 25 water. However, when the polar monomer is N-vinyl ~ ' ' , the use of benzoyl peroxide as the initiator is l~ Examples of such initiators include azo ., 's, l~ydlu~ u~id~ peroxides, and the like, and L~ ;AI~ such as ~. ,..~,l,/ - , benzoin ethyl ether, and 2,2-dimethoxy-2-phenyl ~ lJ~ r 30 Use of a water soluble poly--.~li~Liu.. initiator causes formation of substantial amounts of latex. The extremely small particle size of latex particles _5 renders any significant formation of latex u~.t1~ ~;."h1r The initiator is generally used in an amount ranging from about O.Ol percent up to about lO percent by weight of the total pol~ .i~ltl~ preferably up to about S percent.
Mi~luy~uLcl~t may also be prepared by a simpler ("one-step") S ~ - process comprising aqueous suspension p~ly~ .;~L~tl~ of at least one alkyl (meth)acrylate ester monomer or vinyl ester monomer and, optionally, at least one polar monomer in the presence of at least one emulsifier which is capable of producing a water-in-oil emulsion inside the droplets, which is substantia ly stable during ~ r,- ~'..., and L~ ... In this process the lO aqueous suspension optionally, and preferably, also includes a free radically reactive hydrophilic oligomer and/or polymer.
As in the two-step; ' ~ process, the emulsifier is utilized in ..... I.,l;.~tl~ greater than its critical micelle ~.. - . ,l,~;.. Examples of such emu~sifiers include alkylaryl ether sulfates such as sodium alkylaryl ether 15 sulfate, e.g., TritonTU Wl30, available from Rohm and Haas; alkylaryl poly(ether) sulfates such as alkylaryl poly(ethylene oxide) sulfates, preferablythose having up to about 4 ethoxy repeat units; and alkyl sulfates, such as sodium lauryl sulfate, slmmrts illm lauryl sulfate, i ' -' - lauryl sulfate, and sodium hexadecyl sulfate; alkyl ether sulfates such as 5 lauryl 20 ether sulfate; and alkyl poly(ether) sulfates, such as alkyl poly(ethylene oxide) sulfates, preferably those having up to about 4 ethoxy units. Alkyl sulfates, alkyl ether sulfates; alkylaryl ether sulfates; and mixtures thereof are preferred as they provide a maximum void volume per uy~L~l~ for a minimum amount of surfactant. Nonionic Pm~ ifit r~, e.g., Siponic"5 Y-500-70 25 (t;~.u~L,t~ oleyl alcohol, available from Alcolac, Inc.); and PLURONIC
Pl03 (a block copolymer of PC~ IUYYI~ oxide) and yul~(c~hjlt~ oxide), avlilable from BASF Corporation) can be utilized alone or in ; with anionic emulsifiers. Polymeric stabilizers may also be present but are not necessary.
Both the "two-step" and "one-step" methods produce an aqueous suspension of monomer droplets. Upon poly.,.. li~iiu.l the droplets become 21 ~5226 WO 9~i/27016 r~
.ul,~Licle~. The majority of the ~ U~ iCl~s have interior cavities that, upon drying, become voids.
Another process which may be used to prepare the ~ U Licl~ forms an oil-in-water emulsion and then disperses the emulsion into an aqueous phase.
5 The aqueous phase comprises at least one alkyl (meth)acrylate ester monomer or vinyl ester monomer, and optionally a free radically reactive hydrophilic oligomer and/or polymer. This process employs a suspension stabilizer rather than an emulsifier. As a result, this process forms monomer droplets which have no interior cavities. Upon pol~ .". . ;, 1 ;. ,.. these droplets become solid 10 I~ lu~ ULiCI~.
Discrete polymeric .~ .ulJ~uLicl~ may also be prepared via suspension poly. ;~ as disclosed in U.S.Patent Nos. 3,691,140; 4,166,152;
4,636,432; 4,656,218; and 5,045,569 which all describe adhesive - A "' Preparation of the microparticles of this invention may be modified by 15 withholding the addition of all or part of the optional free radically reactive hydrophilic oligomer and/or polymer, and optionally polar monomers until after pOl~lr.~li~Liu.. of the oil phase is initiated; however, the . l must be added to the pOI,ylll~ ilig mixture prior to 100% conversion.
The ll~i~lU~uLicl~ may be prepared from a number of materials. For 20 example, alkyl acrylate and l..~Lll~ yl~t~ monomers may be used to prepare the spheres. These monomers are ~u..~Liu..~l I ' acrylate and ly' esters of non-tertiary alkyl alcohols. The alkyl groups of these alcohols preferably contain from 4 to 14 carbon atoms. These acrylate monomers are oleophilic, water, 1Cifj~ , have restricted water solubility, 25 and as IIUIIIUPOIYI~ IS~ generally have glass transition i , below about -10C. ~xamples of such monomers include but are not limited to those selected from the group consisting of isooctyl acrylate, 4-methyl-2-pentyl acrylate, 2-.1.elllyll,u~yl acrylate, isoamyl acrylate, sec-butyl acrylate, n-butyl acrylate, 2 ~LIIYIII~AYI acrylate, isodecyl ll,~..ll~ yl~,~" isononyl acrylate, 30 isodecyl acrylate, and mixtures thereof.

Preferred acrylate monomers include those selected from the group consisting of isooctyl acrylate, isononyl acrylate, isoamyl acrylate, isodecyl acrylate, 2-ethylhexyl acrylate, n-butyl acrylate, sec-butyl acrylate, and mixtures thereof.
Acrylate or ~ y' or other vinyl monomers which, as hul~u~uly~ have glass transition ~ , higher than about -10 to 0C, e.g., tert-butyl acrylate, isobomyl acrylate, butyl ~ ,I;Ia~ , vinyl acetate, acrylonitrile, mixtures thereof, and the like, may optionally be utilized in Cullju,..liull with one or more of the acrylate, ..~.~.y' and vinyl ester 10 monomers provided that f~he glass transition; ~ c of the resultant polymer is below about -10C.
Vinyl ester monomers suitable for use in the ll~ u~icl~ include but are not limited to those selected from the group consisting of vinyl 2-ethylh~Y~n~f~, vinyl caprate, vinyl laurate, vinyl ~ ' O vinyl hexanoate, 15 vinyl ~ r' ', vinyl decanoate, vinyl octanoate, and other ~ ' ' vinyl esters of linear or branched carboxylic acids comprising 1 to 14 carbon atoms which as l~u~-o~ul~ have glass transition i below about -10C. Preferred vinyl ester monomers include those selected from the consisting of vinyl laurate, vinyl caprate, vinyl 2 Llh~ , and 20 mixtures thereof.
The polar monomers useful in preparing the ..;_~u~uli~,l.,i. are both somewhat oil soluble and water soluble, resulting in a rlictrihlltion of the polar monomer between the aqueous and oil phases. ~ ,v~ examples of suitable polar monomers include but are not limited to those selected from the 25 group consisting of acrylic acid; methacrylic acid; itaconic acid; crotonic acid;
maleic acid; fumaric acid; sulfoethyl ~ ly' and ionic monomers such as sodium ~l~Ll~oc~ nn~(~n l~ acrylate; sodium acrylate; i ' y - p-vinyl benzimide; N,N-dimethyl-N-(beta-methoxy-ethyl) ~ propionate betaine; ~ lly ' yl~lll;J~, 1,1-dimethyl-1-(2,3-30 dillyd~u~y~lu~yl)amine l~ clyl~ ;dc; N-vinyl IJy~lulidull~ N-vinyl ula~ ; acrylamide; t-butyl a~-yL..--;-lc, dil...~l.yLI...;.lO ethyl a~,yl, I~;d~

wo gsl270l6 2 8 PCTNS9S102295 N-octyl acrylamide; mixtures thereof, and the like. Preferred polar monomers include those selected from the group consisting of " -" -~~mOnU~ U IIUA ylic acids; ~ ~li~lJuA~ylic acids; a~. y N
substituted a~lyl~~ , salts thereof, and mixtures thereof. ~xamples of such 5 monomers include but are not limited to those selected from the group consisting of acrylic acid; sodium acrylate; N-vinyl ,u~ lido..c, and mixtures thereof.
Optionally there may be included free radically reactive hydrophilic oligomers and/or polymers in the ~ lu~al~id~. ;Ahese include but are not 10 limited to those selected from the group consisting of poly(alkylene oxides) such as poly(ethylene oxide); poly(vinyl methyl ether); poly(a~ la.l,id~);
poly-(N-vinyl pyrrolidone); poly(vinyl alcohol); and mixtures thereof.
ru,.. I"",~l;,. .1 derivatives of free radically reactive ~I~ul~ r ~
oligomers and polymers useful in the ~ ,lu~ include those selected from 15 the group consisting of macromers of the general formula:
X~(Y)n~Z
wherein X is a group that is free radically cu,uul~...~li~l,l~ with the free radically polyl.l~li~le monomer(s) and polar monomer(s);
Y is a divalent linking group;
n is an integer of 0 to 1;
Z is a monovalent hydrophilic polymeric or oligomeric moiety having a degree of pOl~ a~iu.. greater than or equal to 2.
l~xamples of such Illa~ include but are not limited to those 25 selected from the group consisting of acrylate and Il~ ~ functional oligomers and polymers, where X represents H2C=CRI-, where Rl represents H or CH3; Y is a divalent carboxyl group; n = I; and Z is a hydlu~llilic oligomeric or polymeric moiety having a degree of pol~"l~.iLd~iull greater than or equal to 2. Such .: also include but are not limited to p-styryl !

_9_ WO 9512~01G PCT/[~S95/02295 functional materials, X represents H2C=CRI-, where Rl represents H or CH3;
Y represents ~CE~2-n = l; and Z is a l~d-u~ ilic oligomeric or polymeric moiety having a degree of pul~ iu~ greater than or equal to 2. D r - 1 or -r ~- 1 oligomers and polymers having more than one X group radically 10 I,u~lylll~.i~bl~ with the free radically cu~l.y ' ' monomers and polar monomers of the ~ u~ ~uL;~ used in the present invention, such X groups either pendant from or i ~ liJd~ 'lir polymeric or oligomeric moiety Z, are also useful in the l..i~up~Li~leJ of the present invention.
Pleferred Illo~ u~ olll~ include those selected from the group 15 consisting of acrylate terminated poly(ethylene oxide); ,.I~,a.c,~l~' terminated poly(ethylene oxide); methoxy poly(ethylene oxide) I..~;lla~l~' , butoxy poly(ethylene oxide) Ill~ lat~" p-vinyl benzyl terminated poly(ethylene oxide); acrylate terminated poly(ethylene glycol); IIl~Lh~.ly;~ terminated poly(ethylene glycol); methoxy poly(ethylene glycol) I~._L;I.,~,I.r' ', butoxy 2û poly(ethylene glycol) ..I.,Ll.~ ~, p-vinyl benzyl terminated poly(ethylene glycol); poly(ethylene oxide) diacrylate; poly(ethylene oxide) d;...~
and mixtures thereof. These ' ' ' materials are preferred because they are easily prepared through well-known ionic polyll..,~ iu.. techniques and are also highly effective in providing grafted hydrophilic segments along free 25 radically polrl..~i~ acrylate polymer backbones.
Preferred ....,~.... ,.. ~..,... ~ also include those selected from the group consisting of p-vinyl benzyl terminated poly(N-vinyl ~ ); p-vinyl benzyl terminated poly(acrylamide); ~ LI~ ,ly~ , terminated poly(N-vinyl ~yllulidull-); and mixtures thereof. These 111.1~11 may be prepared 30 through the . -~ irir~l;-- reaction of a carboxy terminated N-vinyl ~ ulidu.
or acrylamide, beta l~ Luplu~iu~l;c acid chain transfer agent, and wo 95127016 r_l,u,.,s/A~sS
chloromethyl styrene or ~ tll~ luyl chloride as described in a series of papers by M. Akashi et al. tAngew. Makromol. Chem., 1~2, 81 (1985); J. Appl.
Polym. Sci., 39, 2027 (1990); J. Polym. Sci., Part A: Polym. Chem., 27, 3521 (1989] all ill~.Ul~, ' ' by reference herein.
Preferably at least one polar monomer is included in the but I~ u~AI~icl~, may also be prepared using alkyl acrylate, alkyl l"~
and/or vinyl ester monomer(s) alone or in ' only with other vinyl free radically pùlylll~i~lJlc monomers, e.g., vinyl acetate. However, when a tl~ yl~t~ monomer alone is utilized, a ~ ' lcine agent, must be included 10 unless the hydrophilic component comprises more than one radically ~u~oly...~.i~l le group X as defined in Formula I. Most preferably at least about 1 part to about 10 parts by weight polar monomer is included as this ratioprovides ...i~.u~ with balanced PSA properties.
The ,~ ;. ., from which the .. i~lu~ s are made may also 15 contain a .. IIl;r~ .,Al crosslinking agent. The term ~ l" as used herein refers to crosslinking agents which possess two or more free radically p~l.~...~"i~l,l~ ~l..~' Ily, ' ' groups. Useful r, ~ .u ,~li..ki..g agents include those selected from the group consisting of acrylic or .rl~ .ylic esters of diols such as butanediol diacrylate, 20 triols such as glycerol, and tetrols such as l yalli~l. Other useful ~lu~lh~illg agents include those selected from the group consisting of polymeric ' ~ ~ acrylates and .l.Ci~lld~l~' , e.g., poly(ethylene oxide) diacrylate or poly(ethylene oxide) .li..._Ll~ ul~v;ll~
' ' ~ agents, such as substituteo and I ' ~livhl~ll,.,..~..~, and 25 ~iiflmrtinnAl urethane acrylates, such as EbecrylTU 270 and Ebecryl 230TU (1500 weight average molecular weight and 5000 weight average molecular weight acrylated urethanes, respectively - both available from Radcure Specialties), and mixtures thereof.
The microparticles useful in this invention are preferably comprised, 30 based on 100 parts by weight total, of 100 parts or less of at least one freeradically pùlyllll,liLalJI~ monomer selected from the group consisting of aL~cyl acrylate esters, alkyl ~ Lllu~ly' esters, vinyl esters, and mixtures thereof;
and optionally ûbout 0 to ûbout 30 parts by weight of one or more polar lllullvlll~l~, and optionally ûbout 0 to ûbout 40 parts by weight of at least one hydrophilic oligomer or polymer .
Preferably the pressure sensitive l"i~lu~Licl~s comprise about 80 to ûbout 98 parts of free radically puly~.. ";~bl~ monomer selected from the group consisting of alkyl acrylûte esters, alkyl ~ y' esters, vinyl esters, and mixtures thereof; and optionally about 1 to 17 parts of at least one polar monomer; and optionally about 1 to 18 parts of a l~JIv~l~ilic oligomer or 10 polymer ~.omrnnPnt based on 100 parts by weight total. Most preferably the pressure sensitive ~ -uy~u~ s comprise about 87 to about 98 parts of free radically polyl,l~;~lc monomer; and optionally about 1 to 8 parts of a polar monomer; and optionally about 1 to 5 parts of a hydrophilic oligomer or polymer CQmrnn,-~t based on 100 parts by weight total.
When a crosslinker is employed, it is typically employed at a level of up to about 10 equivalent weight percent. Above about 0.15 equivalent weight percent, of the total POIYI~ lu~Li.,le ~ the u~L~
become non-tacky. The ~equivalent weight percent" of a given compound is defined as the number of equivalents of that compound divided by the total 20 number of equivalents in the total (I~ lu~ icl~) . wherein an equivalent is the number of grams divided by the equivalent weight. The equivalent weight is defined as the molecular weight divided by the number of poly...~l;~l,l~ groups in the monomer ~m the case of those monomers with only one yulyl..~l;~lc group, equivalent weight = molecular weight). The 25 crosslinker can be added at any time before 100% conversion to polymer of the monomers of said In;~lu~ iclc ~ Preferably it is added before initiation occurs.
The relative amounts of the above c~ are important to the properties of the resultant I--i~lU~JdlLiCI~. Use of higher levels of a 30 ~ crosslinker will result in nontacky l..i~.u~ulid~,s. In such cases the water sûluble, or ~ r~r~ , polymeric component must be tacky. In 2 t 85226 WO 951Z7016 PCTlllS95/0229S
those cases where the water soluble, or Ai~r~rCihlf~, rolymeric component is notitself tacky, it is necessary for the ~ up~L;cll adhesive to be so.
The W~t~-Dis~ersible Polym~ri~ C~ onent The polymeric component useful in the invention comprises sufficient hydrophilic units capable of rendering the polymer water_Ai~r~;lllf.
Preferably, the po~ymeric component contains functional groups which are capable of interacting with the Illh~l~ ,' Such functional groups include, by way of example, hydroxyl groups, carboxyl groups, amino groups, sulfonyl lû groups, and the like. Adhesives of the invention which employ polymeric ' with these types of functional groups have been found to exhibit improved shear strength.
A wide variety of water-dispersible materials are useful as the polymeric component in the invention. Non-]imiting examples of these materials include 15 those selected from the group consisting of surfactants such as poly(ethyleneoxide) alkylphenyl ethers, such as those sold under the name IGEPAL CO and IGEPAL CA (available from Rl~u..e ~u~l~lC, Inc.); poly(ethylene oxide) lauryl, cetyl, and oleyl ethers such as those sold under the name Brij (available from IC; Americas, Inc.); poly(ethylene oxide) laurate; poly(ethylene oxide) 20 oleate; sorbitan oleate; ethylene oxi~ lu~ oxide block co~,ul~ such as those sold under the name PLURONIC and TETRONIC (available from BASF Cf`rrf~r~tif~n); and organic phosphate esters, such as Gafac0 PE-510 (available from T"t , ~ Specialty Products).
Other water-dispersible polymers useful in the invention include those 25 disclosed in U.S. 2,838,421, U.S. 3,441,430, U.S. 4,442,258, U.S. 3,890,292, and U.S. 5,196,504, and DE-C 23 1176. Examples of such ~f.~ .,t~
include but are not limited to those selected from the group consisting of poly(acrylic acid); poly(vinyl alcohol); poly'~N-vinyl ~llulidu.~
poly(acrylamide); poly(alkoxyalkyl (meth)acrylates), such as 2-ethoxy ethyl 30 acrylate, 2-ethoxy ethyl l~.~LI.~ ' , 2-(2~Lllu~ u~y) ethyl acrylate, and 2-methoxy ethyl acrylate (available from SARTOMER Company, Inc.);

wo ss/27016 ~ )., N ??gS
poly(vinyl methyl ether); poly(vinyl methyl l:Lllc,~ lal~;u anhydride), sold under the name Gantrez~ (available from T, ~ ;.",~l Speeialty Produets); poly(ether polyols), such as poly(~,-u~ .,l glycol) and the like, sueh as those sold under the name SannixsY (available from Sanyo Chemical Industries); CO~O~
5 thereof, and the like. Copolymers of these and alkyl (meth)aerylate esters or vinyl esters are also suitable. Gums sueh as those derived from okra and guar may also be used.
A ~Li~,ul~uly useful water-dispersible polymer eomprises the pressure sensitive emulsion polymers disclosed above. When the emulsion polymer is 10 combined with the ~-iwu~Licl~ ~ a pressure sensitive adhesive is produecd whieh has optimal shear strength. These emulsion polymers eomprise the ~oly,..~i~Liu.. produet of a poly(alkoxyalkyl) aerylate, and a carboxylie acid. Additionally, an essentially water-insoluble alkyl acrylate and a cu~,ol~ emulsifier monomer may be included in the pol.y",~.;~Liu"
15 ,...,,lu,,,, ..l~ The alkyl acrylate typically comprises from 0 to 40 partS by weight, preferably 0 parts by weight, of the ~ol~ li~Lu., mixture. The emulsifier monomer typically comprises from 0 to 6 parts by weight, preferably O to 4 parts by weight, of the pol~ iLaLiu~ mixture.
Examples of poly(alkoxyalkyl) acrylates useful in preparing the emulsion 20 polymer include but are not limited to those selected from 2-(2-~Ll~u~ hv~.y) ethyl aerylate, 2-ethoxyethyl aerylate, 2 ~II-u~ yl aerylate, 2-ll~hVA~ IIYI -.~ ' , POIJ~LIIYI~ glycol IIIVIIV~I,l,~' ' and ...~Lll~ and the like.
Examples of earboxylic acids useful in preparing the emulsion polymer 25 include but are not limited to those selected from aerylie aeid, ~ aeid, itaeonic acid, crotonic acid, maleic aeid, fumaric acid, beta-~l.u.~,ll.yl acrylate, and the like.
Examples of alkyl acrylates useful in preparing the emulsion polymer include but are not limited to those selected from ~ Lllyl(ll.~Lll) acrylate, 30 ethyl(meth)acylttt,n~D~yl~meth)tcrylttt,2~ lt~tyltte, 21 ~5226 wo95127016 1..~ t2~s~
isoamyl acrylate, sec-butyl acrylate, isooctyl acrylate, 2-ethylhexyl acrylate, isononyl acrylate, isodecyl acrylate, and the like.
Examples of ~ul~oly~ i~hlc surfactant monomers useful in preparing the emulsion polymer include but are not limited to those which are anionic 5 vinyl functional cllrf~rt~nt~ such as sodium vinyl sulfonate, sodium styrene sulfonate, alkylene polyalkoxy sulfates, and the like.
Another polymeric component useful in the l~ ulu~uliClC contau~ing adhesive of the invention is described in copending application Serial No.
08/093,080. This application discloses a pressure sensitive adhesive polymer 10 comprised of AA, BB and CC monomers. The AA monomer is a h~
monomer selected from the group consisting of an acrylic or a ' yl;c ester of a non-tertiary alcohol having from 2 to 14 carbon atoms. The AA monomer comprises from 50 to ~0% by weight of AA plus BB plus CC monomers. The BB monomer is selected from ~-~cubw~lllyl aerylate (BCEA) or a salt thereof, 15 and mixtures of BCEA or a salt thereof, and other vinyl carboxylic acids or a salt thereof. The BB monomer comprises from about 10 to about 30% by weight of AA plus BB plus CC monomers. If a mixture of BCEA and the vinyl carboxylic acid or its salt is used, the BCEA must comprise at least 10%
by weight of the polymer. Additionally, the carboxylic acid groups of the 20 polymer have been neutralized with an alkali metal hydroxide. The quantity of the hydroxide used to neutralize the acid groups is from about 0.5 to 2 equivalents of the hydroxide per acid group. The CC monomer is a water-dispersible ~ ul~lol~uLu monomer which has the formula X-Y-Z. In the C
monomer, X is a moiety cu~uly,.,.li~lc with AA and BB, Y is a divalent 25 ]inking group which joins X to Z and Z is a water-dispersible group which eontains at least two units whieh are essentially unreaetive under free radical initiated cu,uolyl~ iull eonditions whieh can be used to form the polymer.
CC eomprises from 10 to 30% by weight of the AA plus BB plus CC
monomers.
This pressure sensitive polymer typically has an inherent viscosity (IV) at 27.5C in l-butanone of from 0.2 to oYer 2 dl/g. Preferably the IV is in the range of 0.7 to 1.5 dl/g. Most preferably the IV is in the range of from 0.9 to 1.4 dl/g.
The AA monomer useful in preparing the terpolymer is a l~ydlu~
~r1nrlmPn~ acrylic or ..I. tl..~lyli~ ester of a non-tertiary aleohol, whieh aleohol 5 eontains from 2 to 14 earbon atoms and preferably from 4 to 12 earbon atoms.
n is preferred that the non-tertiary alcohol be an alkyl aleohol. The term ''lly-llu~JII~;c'' is used herein to mean that the AA monomer laeks substantial affinity for water, that is, it neither substantially adsorbs nor absorbs water at room t~ r Examples of monomers suitable for use as the A monomer inelude the esters of either acrylie aeid or l~ lylic aeid with non-tertiary aleohols sueh as ethanol, I-propanol, 2-propanol, I-butanol, 2-butanol, I-pentanol, 2-pentanol, 3-pentanol, 2-methyl-1-butanol, I-hexanol, 2-hexanol, 2-methyl-1-pentanol, 3-methyl-1-pentanol, 2-ethyl-1-butanol, 3,5,5-trimethyl-1-hexanol, 3-15 heptanol, 1-octanol, 2-octanol, i~uc~ lalcul~ol, 2-ethyl-1-hexanol, I-decanol, 1-dodecanol, I-tridecanol, I-lrl~11f. -....l and the like. The preferred AA
monomer is the ester of acrylic acid with butyl aleohol or isooctyl aleohol or a,..,..l... -l;.... thereof, although c..,..l, ~ c of two or more different AA
monomers are suitable.
Monomer AA is preferably present in an amount of 50 to 80% by weight based on the total monomer content used to prepare the terpolymer.
More preferably monomer AA is present in an amount of 60 to 75% by weight The BB monomer useful in preparing the terpolymer is polar and is cu~,ul~ ' '- with the AA amd CC monomers. It is either BCEA or a salt 25 thereof, or a mixture of BCEA or a salt thereof and vinyl carboxylie aeid sueh as acrylie acid or a salt thereof. Examples of useful vinyl carboxylie aeids include acrylic acid, Ill~ lylic acid, itaconic acid, maleie aeid and fumarie aeid. BCEA is a commereially available material. It is provided as a mixture of ingredients. For example, BCEA is available from Rhone Pûulene, 30 Cranbury, NJ as a mixture of 20 weight % aerylic acid, 40 weight % BCEA
and 40 weight % other acrylic acid oligomers. Preferably, the amount of BB

monomer mixture used to prepare the polymer is in the range of 10-20 weight %.
A n~ ..trAli7ine agent is employed in the , of this polymer. It is employed at a level sufficient to neutr~ e at least 50% of the adhesive 5 copolymer acid moiety. Excess r~ trAli7ine agent, i.e., up to 2 . ~. ' of - li7in~ per acid group may be employed. Preferably from 0.75 to 1.5 equivalents of ~ ,e agent per acid group are employed. ~ is achieved via the use of an alkali metal hydroxide or a ~ ' of an albli metal hydroxide with a minor amount of another . ~, l;,;"~ agent. A wide 10 variety of other n~ rAli7ine agents may be used as will be understood by those skilled in the art. The selection of the other n~ rAli7ine agent, and the amountemployed may be varied to achieve a desired result. However, the type and amount selected must not render tne adhesive non-dic~r~ Preferably sodium and potassium hydroxide are used as ~ agents.
The CC monomer useful in preparing the terpolymer is a water-dispersible ~ .u..~ole~_ul~r monomer. Preferably the CC monomer contains only one vinyl group ~uu~ lc with the AA and BB monomers.
Typically, the CC monomer contains a plurality of hydrophilic sites which impart the required hydrophilicity of the monomer.
A preferred X group of the CC monomer is a vinyl group of the general formula 11 H2C=CRI_ wherein Rl is a hydrogen atom or a methyl group.
A preferred Y group of the CC monomer is a divalent carbonyl group.
A preferred Z moiety of the CC monomer is an ~'i" /pul~.. wi., material with a molecu~ar weight of 300 to 30,000, preferably from 350 to 5,000 and more preferably from 400 to 750. Preferably, the Z moiety is a poly(~lhu~ylu~ ulii~c) or a poly(N-~i..yl~u.ylluli~u.~-) or a poly(alk~ ~,id~) structure. It is also possible to use a Z compound which is a copolymer of 30 different ...~ i,u ~ , e.g. a N-vinylpyrrolidone and a.,ly' ' If such a copolymer is prepared, one of the monomers, e.g. the acrylamide is present only in minor amounts, that is less than 10% by weight.
Monomer CC is preferably present in an amount of from lO to 30% by weight, more preferably in the amount of 15 to 25% by weight of the total 5 monomers.
The ratio of the ~ U~,~uliClc component to the water dispersible component employed in the invention may vary over a wide range of c;, l,v~ For example, the adhesive ~ may comprise from 0.1 to 99.9 parts by weight of the Il~ v~ cl~ and ~
10from 99.9 to 0.1 parts by weight of the water-dispersible polymer It has been discovered that certain narrower ranges of these two . , are preferred for specific utilities. For example, adhesive ~ , , , from about 50 to 95 (preferably from 60 to 95) parts by weight of the lopdlliclc component and, Cull~ from about 50 to 5 (preferably 15 from 40 to 5) parts by weight of the water-dispersible polymer component can be used to provide tapes that are especially useful in paper splicing, 1~
Adhesive ~ ;n"~ that comprise from about 10 to 50 (preferably from 10 to 40) parts by weight of the Ill;.lup~ a and,, , ' ~'~, from about 90 to 50 (preferably from 90 to 40) parts by weight of the water-20 dispersible component are especially useful in closure systems for surgicalwrappers and in n~ l body coverings such as surgical gowns, sheets, drapes and the like. In these ~ the tapes can be used without losing their pressure sensitive adhesive properties during the process. It can also be used with a s~ 7~tinn indicator to indicate that a wrapped package 25 has passed through a ct~rili7~tinn cycle. However, the wrappers and tapes that utilize the adhesive of the invention can be laundered because the adhesive of the invention disperses in alkaline laundering solutions. C~ " the adhesives do not need to be removed prior to Mr,~ifvinF ~rn~
The adhesive blend of the invention may optionally contain one, or more, modifying agents to impart or enhance desired ~ related to the 1~9 ~ of the adhesive or to its ~rrlir~ti~m Modifying agents are 5 generally employed at a level adequate to achieve the desired result without affecting the pressure sensitive properties of the adhesive. Examples of useful modifying agents include, but are not limited to, thickening agents such as those selected from the group consisting of alkali swellable, associative polymers, such as those sold under the names UCAR POLYPHOBE (available from 10 Union Carbide, Inc.); AlcogumTM (available from Alco Chemical); Rheolaten' (available from Rheox); Acrysoln' (available from Rohm & Haas); and Carbopol~ (available from B. F. Goodrich).
N~tr~li7in~ agents, which are often employed in v ~ ';--" with thickening agents or carboxylic acid functional polymers, may also be used in 5 the present invention. Such r- .1l, ,l;,, . ~ include, but are not limited to, those selected from the group consisting of metal ions, such as sodium, potassium, calcium, "~L~ n, copper, aluminum, or _inc; and amines, such as ammonia, and organic amines such as n~ ;,.yld~ , ~ ' amine, h~,A~ yl. n~.l;,.",;..--Other modifying agents which may be used to alter the properties of the adhesive blend include, but are not limited to, those selected from the group consisting of tackifying resins, plastici_ers, pigments, fillers, flow control agellts, and stabili_ers Suitable materials useful as the flexible support or backing for the 25 articles of the invention include, but are not limited to, paper, latex saturated paper, polymeric film, cellulose acetate film, ethyl cellulose film, cloth (i.e., woven or nonwoven sheeting formed of synthetic or natural materials), metallic foil, and ceramic sheeting.
Examples of materials that can be included in the flexible support 30 include polyolefins (such as ~ol~.il,yl~l~, poly~,u~,yl~ ,~c (including isotatic ~vly~Jlv~yl~le)~ pul.~Lyl~ , polyester, polyvinyl alcohol, poly(ethylene WO 95/27016 PCT/US95/0~95 terephthalate), poly(butylene terephthalate), poly(~ ul~ ,oly(vi"ylid~.,.
fluoride), and the like. Commercially available backing materials useful in the invention include kraft paper (available from Mt~n~ln~k Paper, Inc.);
cellophane (available from Flexel Corp.); spun-bond poly(ethylene) and 5 ~OIY(~JIU~ such as TyvekTK and Typarn' (available from DuPont, Inc.);
and porous films obtained from poly(ethylene) and l~uly(~u~fl~ nc), such as Teslinn' (available from PPG Industries, Inc.), and Cellguardn' (available from Hoechst-Celanese) .
The flexible support may also comprise a release coated substrate. Such 10 substrates are typically employed when an adhesive transfer tape is provided.Examples of release coated substrates are well known in the art. They include, by way of example, silicone-coated kraft paper and the like.
Tapes of the invention may also illCul; ' a low adhesion backsize (LAB). Typically this LAB is applied to the tape backing surface that is 15 opposite that bearing the pressure sensitive adhesive. LABS are known in the art.
These and other examples of the invention are illustrated by the following examples which should not be viewed as limiting in scope. Examples of the invention were prepared and examined for 1~11n~PrPhility, tack, adhesion,20 shear and r~Prl-lr~hility. The following test methods were employed.
TPCt Methf ,ic ~k In this test, a Delrin wheel (29 g im weight) with diameter of 8.13 cm 25 and rim width of 1.9 cm is rolled down a plane having a length of 26.7 cm andincline at 24 to a horizontal surface on which the tape to be evaluated is positioned, adhesive side up. The distance the wheel rolls along the horizontal adhesive surface is measured, the tack being inversely ~ l to the distance the wheel travels.

WO9~i127016 .~,I/U.~ 7795 Rev~ n~'~ilif,y Repulpability is measured according to TAPPl test UM-213. For a double-faced tape, one 20 cm x 2.54 cm strip is ~Id~h,h~l bet veen two 20 cm x 2.54 cm strips of blotter paper. For a single-faced tape, t vo 20 cm 5 2.54 cm strips are adhered to blotter paper. The samples are cut into ~plwu~ tdy 1.5 cm squares. A sufficient number of 1.5 cm squares of blotter paper are then added to the tape/blotter paper I ' to provide a total test sample weight of 15 g. The test sample is then placed in a Waring Blender with 500 ml of room t~ , tap water. After the blender has run 10 for 20 seconds, it is stopped for 1 minute while the stock which has splashed up the sides and on the cover of the blender is washed back into the bottom with a water bottle. The blender is then run for an additional 20 seconds, washed down as before, and run for a final 20 seconds. The stock is then removed from the blender and made into a handsheet on a sheet mold. The sheet is 15 removed from the mold, pressed between blotter paper for 90 seconds in a hydraulic press, dried, and examined for any particles Of ~ tape. If two or fewer particles are present, the tape is considered to have passed the test. The presence of one or t vo particles does not constitute failure since these can be due to dirty equipment, or screens. When a material fails the test, the 20 particles will be dispersed throughout the sheet.
The foregoing test does not apply to tape products where, the backing is a material, such as polyester film, which does not lend itself to repulping. TheA;~ y of the adhesive employed on such a backing may be d~
by testing the adhesive film either in the form of an adhesive transfer tape or as 25 a layer on a water-dispersible support layer.
T~.n~Pnr~ T~f A test specimen was produced by laminating a section of tape to be tested to an untreated 50% cotton/50% polyester fabric (available from Standard 30 Textile Co., Cincinnati, OH as Barrier Supreme~). A 1.8 kg (4 Ib) rubber roller was used to laminate the tape to the fabric such that the ~ u~al lidc WO95/27016 r_lr~ r/n~c containing adhesive was left exposed. The test specimen was then steam sterilized using a 134"C, 10-minutes, four-pulse prevacuum cycle and a one-minute steam dry time.
The test specimens were then laundered in a 60 Ib. c ' washing 5 machine (Milnor washer, Model No. 36021BWE/ALA; Pillerin Milnor Corp., Kenner, LA). The specimens went through a typical laundry cycle for surgical linens including: (a) a three-minute cold alkaline brealc in a 0.1% Paralate 55 GLllTM Commercial Liquid Laundry Alkali (Ecolab Inc., St. Paul, MN); a three-minute cold water flush, an eight-minute hot breaWsuds wash using 0.1%
10 of Paralate 55 GLWTM Commercial Liquid Laundry Alkali, and 0.05%
Kindet~M Commercial Liquid Laundry Detergent (Ecolab Inc.); two three-minute hot water flushes; a three minute cold water flush; a ~..~ cold sour/soft rinse using 0.05% Tri Liquid Sour 55GLTM C~ 1 Liquid Laundry Sour (Ecolab Inc.), and 0.05% Tex Special LiquidTM 1~ 1 15 Liquid Denim Lubricant/Softener (Ecolab Inc.), and a six minute extraction to remove excess liquid.
Each laundered specimen was inspected for a pass, meaning that no adhesive residue remained on the fabric, or for a fail, meaning that there was an adhesive residue on the fabric.
Adhesion This test is for 180 peel adhesion to paper. A 3.175 cm strip of bond paper is laminated to a 5 cm x 12.5 cm stainless steel test panel using a double-faced pressure sensitive tape. One end of a 2.54 cm x 25 cm strip of sample 25 tape is then laid over the laminated bond paper (if sample is double-faced tape, then 68 glm2 kraft paper backing is placed on one adhesive side of the sample tape). Uniform adhesive contact is assured by passing a 2 kg roller over the 12.5 cm sample length at a rate of 30.6 mm/minute. The tape is then doubled back on itself and peeled from the bond paper surface at 30.5 cm/minute. The 30 force to remove the tape is recorded using an Instron Model 1122 operated at 21C and 50% relative humidity.

Wo 9sl27016 2 1 85226 p~ SS
,~h~r Stren~th A 2.54 cm x 2.54 cm end portion of a 2.54 cm x 15 cm st}ip of tape is used. If the tape has adhesive on only one surface, that adhesive face is adhered to a bright annealed steel test panel and rolled down with two passes of a 2 ~g 5 roller. If the tape has adhesive on each surface, the adhesive whose shear strength is to be tested is adhered to the bright annealed steel panel and then a section of 68 g/m~ supercalendared kraft paper backing is laminated to the otheradhesive face. The panel is then clamped in a jig which is disposed at 2 to thevertical, so that the 12.5 cm free end of the tape extends downward, at an angle10 of 178~ to the test panel, and a 1000 g weight is attached to the tape end. The time for the tape to separate from the panel is reported in to the nearest minute, the shear stren~th being directly related to the elapsed time. Further details are found in the dru~ i Test Methods for Pressure-Sensitive Tapes, Test PSTC-7. For tapes made with adhesive of this invention, it is desirable to have 15 shear times as high as possible, preferably exceeding 1000 minutes, although an adhesive may be ~Li~r~ ~u~ if its shear time is as low as 40 minutes.
Al~b~
The following al,l,.~viG~io.,s are used in the examples disclosed herein.
AA = acrylic acid 20 BA = butyl acrylate BCEA = beta-~l,.,A~ l acrylate PEOA = poly(ethylene oxide) ~ average molecular weight of 750 EOEA = 2-ethoxy ethyl acrylate EOEOEA = 2-(2-ethoxy)ethoxy ethyl acrylate 25 HDDA = 1,6 ~ ACIllCdiOI diacrylate IOA = isooctyl acrylate MSA = llliclu~ Liclc adhesive PC = water-dispersible polymeric component PPG = P~ U~ glycol) 30 PAA = poly(acrylic acid) PVA = poly(vinyl alcohol) `- ` 21 85226 wo 95/27016 ~ A77AC
Repulp = ~cpl~lpql-ility test P = pass (Rrrlllrq~-ilitY test) F = fail (R~rUlr ~ ity test) The l~ h ~ expression that introduces each ~/IC~ iUII identifies the 5 ,.,~,...." i~ cu~ and the weight ~ of each used in the Mi"l,.v~icl~ Pl~;val~lliull lû Microparticle Colrrnn~nt A (IOA:AA:PEOA/97:2:1) 4.8 g of AA, 2.4 g of PEOA and 1.13 g LucidolTK 70 (70% benzoyl peroxide; available from Elf Atochem) were dissolved in 232 g IOA. 0.75 g Siponate~ DS-10 (sodium dodecyl benzene sulfonate surfactant; available from Rhone-Poulenc) was dissolved in 360 g of water. The IOA mixture was then 15 added to the surfactant solution and emulsified using an Omnin' Mixer until the droplet size was less than 5 microns. The 40 % solids emulsion was then charged to the I liter baffled reactor, heated to 65C, degassed with N2 ailowed to react for 8 hours.
Microparticle Cl~mr~Qn~nt B (IOA:AA:PEOA/89:1:101 2.1 g of AA, 21 g of PEOA, 0.21 g of poly(ethylene oxide)9 dimethacrylate, and 0.99 g of Lucidoln' 70 were dissolved in 186.9 g of IOA.
6 g of StandapoFU. A surfactant ' lauryl sulfate, ~Iercules) was dissolved in 390 g of water. The IOA mixture was added to the surfactant 25 solution, then emulsified using an Omnin' Mixer until the droplet size was less than 5 ,..i~l ulrl~t. l ~. The emulsion was then charged to a 1 liter indented resin flask, heated to 60C, degassed with argon, and ailowed to react for 18 hours.

WO 95127016 2 1 8 5 2 2 6 r~ r7''9';
Micro~rtirl~ ('nnl~nn~nt C (IOA R~ AA pEQA~79 17 1 3) 2.1 g of AA 8.4 g of PEOA, 39.9 g of BA, 0.25 g of HDDA, and 0.99 g of LucidolrY -70 were dissolved in 186.9 g of IOA. 6.5 g of Standapolr". A
S surfactant (a lauryl sulfate, Hercules) was dissolved in 390 g of water. The IOA mixture was added to the surfàctant solution, then emulsified using an Omnin' hIixer until the droplet size was less than S The emulsion was then charged to a 1 liter indented resin flask, heated to 65C, degassed with argon, and allowed to react for 22 hours.
h~iuluv~u~ Comi~n,nn~nt D (IOA:AA ~l~DA/96:~ ~) 4.2 g of AA, 4.2 g of HDDA, and 1.13 g of Lucidoln' -70 were dissolved in 230 g of IOA. 0.75 g of sodium dodecyl benzene sulfonate surfactant was dissolved in 360 g of water. The IOA mixture was added to the lS surfactant solution, then emulsified using an OmnirU Mixer until the droplet size was less than S ,,.i~.u,~.~t~.~. The emulsion was then charged to a 1 liter indented resin flask, heated to 65C, degassed with argon, and allowed to react for 12 hours. The resulting ,.,;clu~Li~ were non-tacky.
~ "u~ iclc ComI~nn~nt E (100% IOA) The Illi~lU~u~iCl~ were prepared in a 1 liter indented resin flask that was charged with 450 ml of deionized water and 4 g of Standapolr". The aqueous solution was stirred at 400 rpm, heated to 70C, and degassed with argon. 150 g of IOA and 0.71 g of LucidollY -70 were added to the hot 25 aqueous surfactant solution. The t~ Lul~; was then r~duced to 65C, and the mixture allowed to react for 22 hours. The ~ average particle diameter was 33 microns as determined by optical Illi~,lU;~UUIJ,y.

W~r-Dis~ersible Polymeric Component Preparation PC-l (EOEOEA:AA/80:20) 1217 g deionized water and 0.39 g potassium persulfate were added to a three liter flask equipped with condenser, agitator, and nitrogen purge line.
5 The mixture was heated to 76C, purged with N2 and, agitated at 150 rpm.
Charges I, II, and In were prepared. Charge I contained 13.5 g MazonT"
SAM-211, Cu~ lly available from PPG/Mazer Chemicals, dissolved in 100 g deionized water. Charge II contained 0.39 g potassium persulfate dissolved in 50 g deionized water. Charge III contained 240 g EOEOEA, 60 g 10 AA, and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge m were added to the flask and reacted for 30 minutes. The remaining portion of Charge III and all of Charge II were then added; .. ~ .. lly to the flask over a 1-2.5 hour period. The contents of the flask were then reacted for an additional 35 minutes after the last charge of ingredients. The emulsified 15 contents were cooled and drained from the flask. They had a pH = 3.32, a Brookfield viscosity = 5 cps, and particle size = 182 ~L.
PC-2 (EOEA:AA/ ~5:15) 800 g deionized water and 0.39 g potassium persulfate were added to a 20 two liter flask equipped with condenser, agitator, and nitrogen purge line. The contents were heated to 76C, purged with N2 and agitated at 300 rpm.
Charges I, II, and m were prepared. Charge I contained 13.5 g Mazon~
SAM-211 dissolved in 100 g deionized water. Charge II contained 0.39 g potassium persulfate dissolved in 50 g deionized water. Charge m contained 25 255 g EOEOEA, 45 g and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge III were added to the flask and reacted for 30 minutes. The remaining part of Charge III and all of Charge II were then added il~ .-~lly over a 1-2.5 hour period. After the last addition the contents of the flask were reacted for an additional 35 minutes. The emulsified contents were cooled and drained 30 from the flask. The polymer had a particle size = 94.3 ~L.

PC-3 (EO~OE~:BA:AA/75:15:10) 800 g deionized water and 0.39 g potassium persulfate were added to a two liter flask equipped with condenser, agitator, and nitrogen purge line and heated to 76C, purged with N2 and agitated at 300 rpm. Charges 1, II, and 5 m were prepared. Charge I contained 13.5 g Mazonr'L SAM-211 dissolved in 100 g deionized water. Charge n contained 0.39 g potassium persulfate dissolved in 50 g deionized water. Charge III contained 225 g EOEOEA, 45 g BA, 30 g AA, and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge m were added to the flask and reacted for 30 minutes. The remaining por~ion 10 of Charge III and all of Charge II were added 1ly over a 1-2.5 hour period. The in~rt~Ai~n~c were reacted for an additional 35 minutes after the last charge. The emulsified contents were cooled and drained from the flask. The polymer had a particle size = 236 ~.
PC-4 (l~OEOEA:BA:AA/70:1~
1672 g deionized water, 20.9 g Mazon~ SAM-211, and 2.1 g potassium persulfate were added to a three liter flask equipped with condenser, agitator, and nitrogen purge line, heated to 76C, purged with N2 and agitated at 200 rpm. A premix containing 292.6 g EOEOEA, 62.7 g BA, 62.7 g AA, and 20 0.30 g t-dodecyl mercaptan were prepared and add to the flask through a dropping funnel over 5 hour period. The emulsified product was then cooled and drained from the flask. The polymer had a pH = 2.46, a Brool~leld viscosity = 4.5 cps and a particle size = 108~.
PC-5 (EOEOE~:BA:AA/50:35: 1~) 1672 g deionized water, 20.9 g Mazon~ SAM-211, and 2.1 g pohssium persulfate were added to a three liter flask equipped with condenser, agihtor, and nitrogen purge line, heated to 76C, purged with N2 and, agihted at 200 rpm for a premix conhining 209 g EO~OEA, 146.3 g BA, 62.7 g AA, and 30 0.21 g t-dodecyl mercaptan was prepared and added to the flask through a dropping funnel over 6 hour period. The emulsified reaction product was then ~ ; 21 85226 WO 95/27016 r~ A779i cooled and drained from the flask. It had a pH = 2.55, a Brookfield viscosity = 4.5 cps, and a particle size = 91.0~L.
PC-6 (EOEOEA-RCEA/82:18) 2000 g deionized water and 0.65 g potassium persulfate were added to a three liter flask equipped with condenser, agitator, and nitrogen purge line, heated to 76C, purged with N2 and, agitated at 150 rpm. Charges I, II, and m were prepared. Charge I contained 22.5 g Mazonn' SAM-211 dissolved in 100 g deionized water. Charge II contained 0.65 g potassium persulfate dissolved in 50 g deionized water. Charge nI contcuned 410 g EOEOEA, 90 g BCEA, and 0.15 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge III
were added to the flask and reacted for 30 minutes. The remaining portion of Charge III and all of Charge II were then added over a 1-5 hour period. The contents of the flask were reacted for an additional 35 minutes after the last 15 charge. The emulsified reaction product was cooled and drained from the flask. It had a pH = 4.47, a Brookfield viscosity = 1.5 cps, and a particle size = 146~u.
PC-7 (EOEOEA:BA:AA/60:~tl:20) 1217 g deionized water and 0.39 g potassium persulfate were added to a three liter flask equipped with condenser, agitator, and nitrogen purge line, arld heated to 76C, purged with N2 and, agitated at 150 rpm. Charges I, II, and m were prepared. Charge I contained 13.5 g Mazonn' SAM-211 dissolved irl 100 g deionized water. Charge II contained 0.39 g potassium persulfate in 50 g dissolved in deionized water. Charge III contained 180 g EOEOEA, 60 g BA, 60 g AA, and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge III
were added to the flask and reacted for 30 minutes. The remaining Charge m and all of Charge II were then added over a 1-2.5 hour period. The contents of the flask were then reacted for an additional 30 minutes after which they were 30 cooled and drained. The emulsified reaction product had a particle size = 101 ~L, and Brookfield viscosity = 5.0 cps ~WO 95127016 r~
PC-8 (EOEOEA:IOA:I~-t'F~150:17:33) 1220 g deionized water and 0.39 g potassium persulfate were added to a three liter flask equipped with condenser, agitator, and nitrogen purge line, heated to 76C, purged with N2 and, agitated at 150 rpm. Charges I, II, and 5 m were prepared. Charge I contained 13.5 g Mazonn' SAM-211 dissolved in 100 g deioniied water. Charge II contained 0.39 g potassium persulfate dissolved in 50 g deionized water. Charge III contained 150 g EOEOEA, 51.0 g IOA, 99.0 g BECE, and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge III were added to the flask and reacted for 30 minutes. The 10 remaining Charge III and all of Charge Il were then added over a 1-3 hour period. The contents of the flask were reacted for additional 35 minutes. The emulsified reaction product was cooled and drained from the flask. It had a pH
= 3.32, a Brookfield viscosity = 3 cps, and a particle size = 210~L.
PC-9 (EOEOEA:AA/95:5) 800 g deionized water and 0.39 g of potassium persulfate were added to a two liter split resin flask equipped with condenser, agitator, and nitrogen purge line, and heated to 76C and, agitated at 150 rpm. The flask was purged with 1 liter per minute N2. Charges I, II, and In were prepared. Charge I
20 contained 15.0 g Mazon~K SAM-211, dissolved in 100 g deionized water.
Charge II contained 0.39 g potassium persulfate dissolved in 50 g deionized water. Charge III contained 285 g EOEOEA, available from Sartomer Chemical Co., 15 g AA, and 0.09 g t-dodecyl mercaptan. Charge I and 75.0 g of Charge m were added to the flask and reacted for 30 minutes. The 25 remaining Charge III and all of Charge II were then.added over a 1-2.5 hour period. The contents of the flask were reacted for an additional 30 minutes after which the emulsified reaction product was cooled and drained from the flask.

WO 95127016 ~ 4 PC-IO nOA:AA/85:15) 800 g deionized water and 0.39 g F,otassium persulfate were added to a two liter split resin flask equipped with condenser, agitator, and nitrogen purge line. The reactants were heated to 76C, purged with N2 (I l/min) and, 5 agitated at 150 rpm Charges I, and II, were prepared. Charge I contained 13.5 g Mazonn' SAM-211 dissolved in 100 g deionized water. Charge II
contained 225 g IOA, 45 g AA, and 0.09 g t-dodecyl mercaptan. Charge I
and 75 g of Charge II were added to the flask and reacted for 30 minutes at 76C. The remaining portion of Charge II was then added over a 2 hour 10 period. The contents of the flask were then reacted for an additional 30 minutes. The resulting emulsified reaction product was then cooled and drained from the flask. It had a solids content of 26.8% by weight and a particle size of 128, ~ . . s.
PC-ll (EOEOEA:AA/90:10) 2403 g deionized water and 1.17 g potassium persulfate were added to a five liter flask equipped with condenser, agitator, and nitrogen purge line. Thereactants were heated to 76C, purged with N2 and, agitated at 150 rpm.
Charges 1, II, and m were prepared. Charge I contained 40.5 g Mazonn' 20 SAM-211 dissolved in 297.0 g deionized water. Charge II contained 1.17 g potassium persulfate dissolved in 100 g deionized water. Charge III contained 810 g EOEOEA, 90 g AA, and 0.27 g t-dodecyl mercaptan. Charge I and 300 g of Charge m were added to the flask and reacted for 30 minutes. The remaining Charge III and all of Charge II were then added over a 1-2.5 hour 25 period. The contents of the flask were then reacted for an additional 30 minutes. The resulting emulsified reaction product was then cooled and drained from the flask.
PC-12 (EOEOEA:AA/90:10) 62.3 kg deionized water and 21.2 g potassium persulfate to a 25 gallon (951) glass-lined reactor and heated to 76C. The contents of the reactor were agitated at 75 rpm and purged with N2. Charges I and II were then prepared.
Charge I contained 1.6 kg AA, 735 g Mazon~ SAM-211, 14.7 kg EOEOEA, and 4.9 g t-dodecyl mercaptan. Charge II contained 5.3 kg deionized water and 21 2 g potassium persulfate. 4.3 kg of Charge I were added to the reactor and S reacted for 30 minutes. The remaining Charge I and all of Charge II were then added to the reactor over a 1.5-2 hour period. The contents of the reactor were reacted for an additional one hour. The resulting emulsified reaction product was cooled and drained from the reactor. It had a particle size = 228~, and a Brookfield viscosity = 4 cps.

EY~m~r1.~ 1-10 Adhesive tape samples employing only Mic.ul,~uLi~l~ C . A-E
were prepared by mixing the IlI-UlU~ with 1% by weight of an associative, alkali-swellable thickener, (TJCAR Polyphoben' 104, available from 15 Union Carbide) and neutralized with potassium hydroxide and poly(u,~ u~yl r)tri~mine to a pH of 7. The adhesive was coated on a release surface and dried in a oven at 79C for three minutes This was laminated to rcrystex" tissue paper to provide a single sidcd W -~llU-,liUI~. To obtain a double sided construction, adhesive was coated onto the opposite side of the 20 single sided sample and dried in a similar manner. Testing was conducted after removal of the release liner.
Adhesive tape samples for Examples 1-10 were prepared by mixing the Mi1lu~1iclc Comrnnrnt A with the desired water soluble, or ~ r~ r polymeric cnm~mnr~nt then thickened, ~r.~r~1j7~i and coated in the same 25 manner as used with the tapes made from Mi.,.u~ lc ~': , A-E
above. The water soluble, or ~i~r~rcihl~, polymeric , employed were an organic phosphate ester, Gafac PE-510, available from l ~t . ~
Specialty Products; poly(vinyl alcohol), PVA, with a molecular weight of 8 x 105 g/mol; poly(acrylic acid), PAA, with a molecular weight of 2 x 105 g/ mol;
30 poly(ethylene oxide), PEO, with a molecular weight of 106 g/mol; et;.u,.y alkylphenols, Igepal CA-520, CA-630 and C0-630, available from WO 95/2701G ~ /U~
T, ~ ."'l;.. I Specialty Productc; poly(alkylene glycol), Sannix't SP-750, available from Sanyo Chemical Industries; and PUIY(~IU~ ~ glycol), PPG, with a molecular weight of 400 g/mol.
These examples show that addition of a water soluble, or ~ ~r~
5 polymeric component to a ~ u~ adhesive provides enhanced w~ C~ in tack while _ repulpability. These results are recorded in Table 1.
TABLE I
Repulp 10 Example Polymeric Cnmrnmnt % P.C. Tack Test (mm) (PlF) Control None . 0 80 P
(All Mi~l ul,~u Lidc ~ A) Gafac PE-510 0.5 15 P
2 Gafac PE-510 1.0 20 P

3 PVA 1.0 33 P
15 4 PAA 1.0 38 P
5 PEO 1.0 29 P
6 Igepal CA-520 2.5 48 P
7 Igepal CA-630 2.5 47 P
8 Igepal C0-630 2.5 36 P
20 9 Sannix~ SP-750 5.0 30 P
PPG 5.0 33 P
F~mrPc 11-21 Examples 11-21 were prepared in the same manner as Examples 1-10 25 using Mi~lulJ~Li~lC Component A and the Polymeric C~ , indicated im Table 2. However, no thickening agent was added.
These examples show that when the water soluble, or .iicr~
polymeric component added is a PSA, the adhesion p r..". ~ is improved in ~WO95/27016 P~,l/LI.~_.. -all cases, as is the tack in most cases, while IIIA;I ~ rerlllp~l-ility. The results are recorded in Table 2.

PC Repulp polymeric Cnmrn~nt Tack Test Adbesion Example rnmrnnPn~ (%) (mm) (P/F) ~/cm) (PC) None (All 0 80 P 3.6 Control Mic~ ~ Licl~
~nmrnn~ nt A) 11 PC-l 22 56 P 6.9 10 12 PC-2 22 17 P 8.0 13 PC-3 22 20 P 7.3 14 PC-4 22 123 P 7. 1 15 PC-5 22 79 P 6.9 16 PC-6 22 14 P 8.4 15 17 PC-7 13 38 P 6.3 18 PC-8 13 20 P 7.1 19 PC-l 13 33 P 6.4 20 PC-9 13 21 P 5.8 21 PC-10 22 32 P 6.0 F~ c 22-33 In Examples 22-33 the water soluble, or (1icln~-r~ , rolymeric component used was PC-ll and the Mi~ ~Liclc r , was Mi~ icle r: . A. Example 22 was prepared in tbe same manner as 25 Example l; and Examples 23-32 were prepared in the same manner as Example 11. Example 33 was neutralized as described in Example 11.
These examples ~ the properties of tbe invention over a wide range of polymeric component c~ The results show enhanced WO95/27016 r~ m ' 7~5 in tack and adhesion and in shear (in most cases), while repulpability is m~int~in~l, with respect to Control A as recorded in Table 3.

S Polymeric Tack Repulp Adhesion RT
Example t"-~r (mm) Test (N/cm) Shear (%) (P/F) Adhesion (min) Control 0 (All 80 P 3.6 1330 A Mi.,lu~,~licl~
~nm~n~nt A) 22 S 62 P 5.4 2800+
10 23 9 37 P 5.4 2800+
24 13 24 P 5.4 2800 +
25 23 21 P 6. 1 2800+
26 31 18 P 6.1 2800+
27 38 18 P 5.7 2800+
15 28 43 22 P 6.1 2020 (Shear) 29 47 22 P 6.5 1650 (Shear) 30 60 35 P 5.7 130 (Shear) 31 75 33 P 5.9 76 (Shear) 32 90 39 P 5.9 S7 (Shear) 20 33 100 31 P 7.8 130 (All PC-ll) (Shear) -WO 95/27016 r_l",,, /n~9~;
Control A popped off after 1330 minutes. EJ~amples 28, 29 and 33 sheared at the indicated time.
F.~ c 34-38 These Examples show the effect of combining a water~
polymeric c~rrm~n~ consisting of a copolymer of EOEOEA and acrylic acid at various ratios, with different types of ' -r li!cl~ adhesives. E~an~s 34, 35, 36, 37, and 38 (with a polymeric .~ l . l) were prepared in the same manner as Example 11.
Control B and Example 34 compare ~ u~
which contain 10% PEOA. Control B employs no polymeric ~ l ~
Example 34 employs 22% by weight of PC-5. Ill~ ulali~l~ of PC-5 rc~lts in improved adhesion and rerl-Ir~iIity as shown in Table 4.

15 Example Mi~ PC Tack Repulp Adhes~on ~-n~n~ Component (mm) Test ~lc~) (PIF) Control B B --- 19 F 5.8 34 B PC-S 35 P 6.7 Control C and Example 35 compare ' ~ , "' which 20 contain PEOA and butyl acry~ate. Control C employs no polymeric .
Example 35 contains 22% by weight PC-1. ~ JUldiUn of PC-l results in improved adhesion and r~r--lp~lility as shown in Table 5.
TABLE, ~
Example Mi~lu~Li~l~ PC Tack Repulp A~Dn .m.~n~ (mm) Test (N/cm~
(PIF) 25 Control C C --- 33 F 3.7 35 C PC-1 180 P 5.6 WO 95/27016 p~ gc --Control D and Examples 36 and 37 compare ~ U~ J~
which are tack free. Control D employs no polymeric ~ , Examples 36 and 37 employ 33 and 43 weight percent PC-4, ~ ly. T
of PC-4 results in improved tack and adhesion, while 1" lCr 1 5 as shown in Table 6.

Example Microparticle PC Tack Repulp Adhesion C~ , (mm) Test (N/cm) (P/F) Control D D --- ~ #** P ***
10 36 D PC~ 150 P 1.3 37 D PC-4 150 P 2.9 ***tack free, unable to test Control E and Example 38 compare Illi~,lU~J~lLiCI~ C~ which are large in size, diameter = 33 Il~i~ lu~ t~ relative to all other Examples disclosed herein in which the diameter is ~ IU..illldt~ 3 ~ ,lUII.~
Control E employs no polymeric comrnn~nt Example 38 employed 43 percent by weight of PC-12. I~ uluu~liù~ of PC-12 results in . u.. in tack 20 and repulpability.

Example Microparticle PC Tack Repulp Adhesion ~nmrnnPn~ t'nmrnnPn~ (mm) Test (N/cm) (P/F) Control E E --- 170 F 6.1 38 E PC-12 130 P 4.1 Fs~nlT)lP~ 39-42 Pressure sensitive adhesive tapes of the invention were prepared, laminated to untreated 50% cotton/50% polyester fabric (Barrier Supreme"') and laundered as described in the T ~-ln~Pnn~ Test. The backing employed in the tape was "Crystex" tissue paper. The adhesive ~ tested and the results obtained are set out in Table 8.

s Mi~lUp~llLiCIe (~ A ' Water-Dispersible C
Example Mat'l. Parts by Weight Mat'l. Parts by Weight 10 41 A 87 PC-l 13 All samples showed no evidence of residue on the laundered fabric.
Fx~mr~l. 43 A water-dispersible polymer was prepared. First, a mono-l,letl.uAypul~;llyl(eneglycol) acrylate monomer with a molecular weight of 750 was prepared by Fischer ~-cf~nfi~finn of Carbowax~ 750 (Union Carbide).
One hundred parts of the Carbowax'U 750 and 100 parts of toluene were 20 introduced to a flask which was equipped with a Dean-Stark condenser and a stirrer. The solution was heated to reflux ~ ..,l.. .~1l",= for two hours. 11.3 parts of acrylic acid, 4.5 parts of p-toluene sulfonic acid, 3,000 ppm of Irganoxm PS 800 (Ciba-Geigy) and 500 ppm r' '- ' ~ were added into this mixture. The solution was heated to reflux ~ c for another 16 hours.
25 After cooling down to room ~ . excess acid was neutralized with 4.5 parts of calcium hydroxide. The formed precipitate was filtered off.
v~ lly the toluene was evaporated under reduced pressure to yidd a solid 100% acrylate monomer.
A water-dispersible pressure sensitive adhesive polymers was prepared by charging butyl acrylate (BA), BCEA (.ul.lln.l~;.,lly available as a mixture of wo 95/27016 PCTIUS951022gS
20 weight % acrylic acid, 40 weight % BCE A, 40 weight % other acrylic acid oligomers from Rhone Poulenc), the mono~ l.u,.~ l.yl~,~gly~l) acrylate monomer to a one quart bottle containing a solvent mixture of ethyl acetate, methanol and isopropanol, and 0.51 grams ,.1.~ ' I"ne 5 monomer charge comprised betwoen 32 and 34% of the p~l~...~i~liu..
mixture. The mixture was d~.J~ d by purging with one liter per mihute nitrogen for two minutes. The bottle was sealed and placed in a rotating water bath at 55C for 24 hours to effect essentially complete pol~ The inherent Yiscosity (IV) of the resultant polymer was then measured in 2-10 butanone at 27.5C. N~ l.,.li,;l.~ agent (86.8% pure KOH, 1.25equivalents based upon 100% pure KOH) in a 3.57 N 50:50 methanol:water (V/V) solution was blended into the adhesive pûlymer. M; '`'l ~ I .. l. ~ (A) w~re then mixed into the adhesive polymer to give a final ratio of 20 g to 100 g adhesive polymer (i.e., 16.7% .~ .u~ by weight).
15 The resultant neutralized .,li.. u~ containing pressure sensitive adhesive .-. ,~ i(." was applied to a 29 pound basis weight Kraft paper (M-2383) Smooth Crepe Semi-Bleached Kraft Saturating Paper from Mosinee Paper Corporation of Mosinoe, Wisconsin) to form a closure tape as describod below.
The pressure sensitive adhesives in the solvent system were coated on the Kraft paper at 0.68 grams per 154.8 cm2 (24 in2) using a standard laboratory knife coater, with drying for 15 minutes in a forced air oven at 100C.
Table 9 shows the initial adhesion, post-st~ ~ili7~ti~- adhesion, pre-25 ~ rili7~tir~n wrapper closure (T(0)), post-ct~rili7~ti~n wrapper closure ~A, and rlic~rr;l~ility of the closure tapes of Example 43 and Cu..l~al~Li~
Example I on a lluulu~ lly-treated pûlyester wrapper. The following test procedures were utilized.

WO 95/2701G P~ n7~c l~itial Adhesion to TrP~t~l~)r~e Wr~rs Samples of a lluulu~l..".,i~lly-treated polyester drape (available from Standard Textile Co., Cincinnati, OH as WrapPels'' T) were cut into 3.81 cm by 10.16 cm strips and adhered with #410 double coated tape available from the 5 3M Co.) to a 5.08 cm by 12.2 cm steel plate. Example closure tapes of the invention (2.54 cm by 10.16 cm) were applied to the drape and were rolled twice with a 2 kg rubber roller.
One end of each of the plate was placed in the jaws on an Instron Model 1122 tensile tester (Instron Corp., Canton, MA), while one end of the closure 10 tape was adhered to the opposing set of jaws of the tensile tester to allow removal of the tape from the drape at essentially a 180 peel angle. The rate ofjaw movement was 30.48 cm/minute and the tensile tester recorded the force required to separate the tape laminate from the drape. The results were recorded in Newtons per 2.54 cm (N/2.54 cm). The initial adhesion 15 , ~ derives from the fact that the dwell time of the tape on the drape was short; i.e., the example tape was applied and peeled without a long residence time (i.e., less than 5 minutes) in between, and ! ' '- '- had not yet taken place.
Post-sterili7~tinn A~lh~;nn to TrP~tPA Dr~P
The same method as the initial adhesion test was used for this test, except that prior to testing, the example closure tapes were steam steriliz_d at a setting of 273F (134C), in a 10 minute gravity cycle with a three minute steam dry time. The sterilizer used was a Barnstead Model GLS-IOD (MDT
25 Biologic Co., Rancho Dominquez, CA). In addition, the laminate was allowed to cool at room r "l~ for a minimum of 4 hours before peel testing. The results were recorded in N/2.54 cm.

2 t 8 5226 wo sst270l6 .
,~tz~ti~ Shear Str~ ~h The tapes were tested for static shear strength as follows. A stainless steel plate was washed with diacetone and wiped with a tissue (KIM-WIPE) and then washed again with heptane followed by wiping with a tissue. The heptane 5 wash was repeated two more times. A length of the tape was applied to the WraPeln' T drape material to provide a 2.54 cm by 2.54 cm bond area. The remainder of the tape hung over the edge and was doubled back to form a loop.
A 2 kg roller was passed back and forth over the bond area once in the length direction of the tape. A 250 g weight was hung from the loop and the resulting 10 assembly hung vertically in a room maintained at 20C and 50% relative humidity. The time to failure (i.e., the time for the tape to fall from the stainless steel plate) was measured.
Table g Property Initial Adhesion 229 N/2.54 cm Post S~P~ili7~ti-n Adhesion (N/2.54 cm) 88 N/2.54 cm Static Shear 88 min 20 D;~ ibilily Pass While this invention has been described in terrns of specific ~..,I,o.l"~ it should be understood that it is capable of further, r~ "
25 The claims herein are intended to cover those variations one skilled in the art would recognize as the chemical equivalent of what has been described here.

Claims

What is claimed is:

1. A water dispersible normally tacky pressure sensitive adhesive composition comprising a blend of:
A) a polymeric, elastomeric, solvent insoluble but solvent dispersible microparticle component and B) a water-dispersible polymeric component, wherein said adhesive composition is repulpable when tested according to TAPPI
test UM-213.

2. A pressure sensitive adhesive composition according to claim 1 comprising from about 0.1 to 99.9 parts by weight of said microparticle component, and correspondingly from 99.9 to 0.1 parts by weight of said water-dispersible component.

3. A pressure sensitive adhesive composition according to claim 1 wherein the microparticle portion of said microparticle component is either a solid particle or a particle containing at least one void.

4. A pressure sensitive adhesive composition according to claim 3 wherein (A) the microparticle component comprises the polymer of:
(1) 100 parts by weight or less of at least one free radically polymerizable monomer selected from the group consisting of alkyl acrylate esters, alkyl methacrylate esters vinyl esters and mixtures thereof;
(2) 0 to 30 parts by weight of at least one polar monomer copolymerizable with the free radically polymerizable monomer of part A(1); and (3) 0 to 40 parts by weight of at least one hydrophilic oligomer or polymer copolymerizable with either of the free radically polymerizable monomer A(1) and the polar monomer A(2), and (B) the water-dispersible polymer component comprises the polymer of:
(1) 50 to 98 parts by weight of a water soluble poly(alkoxyalkyl) acrylate; and correspondingly (2) 50 to 2 parts by weight of a carboxylic acid.

5. A pressure sensitive adhesive composition according to claim 4 wherein the microparticle component comprises from about 80 to 98 parts of the free radically polymerizable monomer, from about 1 to 17 parts by weight of the polar monomer and from about 1 to 18 parts by weight of the hydrophilic oligomer or polymer.

6. A pressure sensitive adhesive composition according to claim 5 wherein said hydrophilic component comprises macromonomers of the general formula X-(Y)n-Z
wherein X is a group that is free radically copolymerizable with the free radically polymerizable monomer and optional polar monomer(s);
Y is a divalent linking group;
n is an integer of 0 to 1; and Z is a monovalent hydrophilic polymeric or oligomeric moiety having a degree of polymerization greater than or equal to 2.

7. A pressure sensitive adhesive composition according to claim 5 wherein the water-dispersible polymer component further comprises from about 0 to 40 parts by weight of an essentially water-insoluble alkyl acrylate and from 0 to 6parts by weight of an emulsifier monomer.

8. A pressure sensitive adhesive composition according to claim 7 wherein the water-dispersible polymer component comprises from about 80 to 95 parts by weight of said poly(alkoxyalkyl) acrylate, from about 20 to 5 parts by weight of said carboxylic acid, and from about 0 to 4 parts by weight of said emulsifier monomer.

9. A pressure sensitive adhesive sheet comprising a layer of the water dispersible normally tacky pressure sensitive adhesive of claim 1.

10. A pressure sensitive adhesive sheet according to claim 9 wherein said layer of normally tacky pressure sensitive adhesive is provided on at least one surface of a flexible support.

11. A pressure sensitive adhesive tape according to claim 10 wherein said layer of normally tacky pressure sensitive adhesive is strippably bonded to saidflexible support.

12. A pressure sensitive adhesive tape according to claim 10 wherein said layer of normally tacky pressure sensitive adhesive is essentially permanently bonded to said flexible support.

13. A pressure sensitive adhesive tape according to claim 12 wherein said tape is repulpable.

14. A repulpable, pressure sensitive adhesive tape comprising a thin layer of the normally tacky pressure sensitive adhesive composition of claim 1, wherein the microparticle component is a suspension polymerized material.

15. A water-dispersible pressure sensitive adhesive tape according to claim 14 comprising from 10 to 95 parts by weight of said microparticle component and correspondingly from 90 to 5 parts by weight of said water-dispersible polymeric component.

16. A repulpable pressure sensitive adhesive tape according to claim 15 comprising from 50 to 95 parts by weight of said microparticle component and correspondingly from 50 to 5 parts by weight of said water-dispersible polymeric component.

17. A launderable pressure sensitive adhesive tape according to claim 15 comprising from 10 to 50 parts by weight of said microparticle component and correspondingly from 90 to 50 parts by weight of said water-dispersible polymeric component.

18. A launderable pressure sensitive adhesive tape according to claim 17 comprising from 10 to 40 parts by weight of said microparticle component and from 90 to 60 parts by weight of said water-dispersible component.

19. A pressure sensitive adhesive tape according to claim 14 wherein said microparticle component is pressure sensitive.

20. A pressure sensitive adhesive tape according to claim 14 wherein said water-dispersible polymeric component is pressure sensitive.

21. A fabric bearing the pressure sensitive adhesive tape of claim 18.

22. A fabric according to claim 21 in the form of a mammalian body covering.

23. A pressure sensitive adhesive tape according to claim 10 in the form of a sterilization indicator tape.

24. A splice comprising first and second repulpable sheets joined together by a pressure sensitive adhesive tape according to claim 14.

25. A water-dispersible pressure sensitive adhesive polymer useful as part B) of claim 1 comprising the emulsion polymerization product of:
A) from about 50 to 98 parts by weight of a poly(alkoxyalkyl)acrylate; and correspondingly B) from about 50 to 2 parts by weight of carboxylic acid; and C) from about 0 to 40 parts by weight of an essentially water-insoluble alkyl acrylate: and D) from about 0 to 6 parts by weight of an emulsion monomer copolymerizable with either of said poly(alkoxyalkyl)acrylate or said carboxylic acid.

26. A pressure sensitive adhesive sheet comprising a layer of a normally tacky pressure sensitive adhesive polymer according to claim 25.

27. A pressure sensitive adhesive tape according to claim 26 wherein said layer of said pressure sensitive adhesive polymer is provided on at least a portion of at least one surface of a flexible support.

28. A pressure sensitive adhesive tape comprising a flexible, repulpable support layer, a layer of a normally tacky pressure sensitive adhesive polymer according to claim 25 on at least a portion a first side of said support layer, and a layer of a release agent on at least a portion of a second side of said support layer, said second side of said support layer being opposite said first side of said support layer.