CA2228310A1 - Heat resistant dry cleaning bag - Google Patents

Abstract

A dry cleaning process is conducted in a hot air clothes dryer using a containment bag. The bag is constructed using heat resistant polymers, such as nylon, to avoid unanticipated hot spots in the dryer. The bag retains its integrity and can be re-used in subsequent dry cleaning operations.

Description

HEAT RESISTANT DRY CLEANING BAG

FIELD OF THE INVENTION
The present invention relates to fabric dry cle~ning which is cond~lcte~ in a bag-type Co../A;..~. in a hot air envi~or....~t CROSS REFERENCE
This applirati~)n claims priority under Title 35, United States Code ll9(e) from Provisional Application Serial No. 60/002,167, filed August 11, 1995 and Provisional Application Serial No. 60/005,684, filed October 17, 1995.
BACKGROUND OF THE INVENTION
By rl71e~ 1 d_r.~ ;O~, the term "dry cle~ning" has been used to describe p.ocesses for cl~ni~ textiles using nonaqueous solvents. Dry cleaning is an old art, with solvent ~ g first being recorded in the United Kingdom in the 1860's.
Typically, dry cle~ning processes are used with gall~rc;llls such as woolens which are subject to shrinkage in ~q~leollc laundering baths, or which are judged to be too valuable or too delir~te to subject to ~queo~ls laundering processes. Various L~,.l,oc~ul,oll and halocarbon solvents have tr~tlition~lly been used in illllll.;l~ion dry .c pro.ecs~C and the need to handle and reclaim such solvents has mainly restricted the practice of convention~l dry cl~ni.~ to co~ ,;al eSt~h!i~h..~
While solvent-based dry rl~n;..~ proce.,ses are quite effective for removing oily soils and stains, they are not optimal for removing particlll~tt~c such as clay soils, and may require special ll~ c-~ corl~litionc to remove pl~lf ~l~ceolls stains. Ideally, partiCIll~t~s and IJlot~ ceoll~ stains are removed from fabrics using detersive ingl~di~.,~ and OpC.ali~lg con~itior~ which are more akin to ~queo!l~ launderingplocesseS than to conv~ntinn~l dry rl~zmir~g In s~dA;ti~n to the ~ ;"~ filnction, dry cle~ning also provides UllpOl l~LIII
... r.~ For ~ . Iç, dry ~ B removes unde~i, ble odors and ~ h ~IW~1S matter such as hair and lint from ga~ , which are then generally folded or pressed to remove wrinkles and restore their original shape. Of course, such l~,rl~ :h...~ .1 benrr~c are also afforded by ~ eolls laundering procPcses As can be seen from the foregoing, and aside from the effects on certain fabrics such as woolens, there are no special, inherent adv. n~ P~ for solvent-based e.~;ol~ dry ~le~nin~ over ~qlleolls clp~ning processes with respect to fabric clP~ning or lcr~ nl Moreover, on a per~ clll basis, conl,.-l .-;ial dry cle~ningis much more e,~ ns;~e than ~leo~1s Cle~ninE procescPc- Acco-di~Jy, it would be of conQ;derable benefit to consumers to provide non-;l.~ ,;on dry clP~ning p.ocesses which can be used in the home.

.

One type of home dly cleaning system comprises a carrier sheet cont~ining various cleaning agents, and a plastic bag. The garments to be cleaned are placed in the bag together with the sheet, and then tumbled in a conventional clothes dryer. In a commercial embodiment~ multiple single-use flat sheets and a single multi-use plastic bag are provided in a par~ e The present invention is directed to the solution of a problem which appears to have been heretofore unrecognized in the home dry r,le~ning field. It has now been discovered that some conv~ntion~l laundly dryers, which otherwise appear to be filnctioning quite normally, can reach air and surface te."pe,al~res which exceed the ~Yrected norms for this t,vpe of appliance. Specifically, air temperatures in various regions of the dryer drum can reach 250~F (121~C) to 300~F (149~C), and surface temperatures of 350~F (177~C) to 400~F (204~C) have been recorded. Such hot spot~e.,.~,.al~res are very much higher, e.g., 100-250~F (39-120~C) than the programmed Opc,a~ g temperatures used in conv~ntion~l dryers. This situation appears to be ~u~ish~gly wide-spread and seems to affect 5-10% of the dryers which have been investi~te-l Upon due concid~ration, the development of such hot spots can be presumed to result from poor dryer venting, clogged lint filters, m~lfi7nr,tir~ning ttn~ ,.al~lre sensors, or co...ls;~ ;o.-c of such factors. Whatever the rewn, the development of such high te...p~.al-lres has now been found to cause ~m~ccept~ble melting or fusing of convçntiQn~l plastic bags used for in-home dry r, l~nir~g Such bags are then rendered un~ce~l~hle for Imlitirle uses. In e,~l~e...c ~ -ces, loss of bag i~ltt~ily can subject ~a,.,lC.lL~ to un~ccepl-~hly high t~ a~u,~,s. By the practice of the present invention, dry ~ ,g bags Colll~ g a heat-re~
polymer such as nylon are used to o~,e,co--.c this problem. ~ O.L~.LlY, this allows the bag to be re-used in subsequent dry-cle~ni~ operations.
BACKGROUND ART
Dry clP~l~;ng ~rocesses are ~icrlQsed in: EP 429,172Al, publieh~d 29.05.91, Leigh, et al.; and in U.S. 5,238,587, issued 8/24/93, Smith, et al. Other ,.,f~,rences relating to dry cleA ~; ~g col.~l.G3:l;one and proc~cec, as well as wrinkle ll~n~ c for fabrics, include: GB 1,598,911; and U.S. Patents 4,126,563, 3,949,137, 3,593,544, 3,647,354; 3,432,253 and 1,747,324; and Gennan app~ic~tiorlc 2,021,561 and

2,460,239, 0,208,989 and 4,007,362. Cle~nin~ll:-spotting con~rositiQn~ and m~th(-lc are also disclosed, for ex~mple~ in U.S. Patents 5,102,573; 5,041,230;
4,909,962; 4,115,061; 4,886,615; 4,139,475; 4,849,257; 5,112,358; 4,659,496;
4,806,254; 5,213,624; 4,130,392; and 4,395,261. Sheet :,ub:iLlales for use in a laundry dryer are disclosed in (~n~ n 1,005,204. U.S. 3,956,556 and 4,007,300 relate to p~,.r~,raLed sheets for fabric con~litiQning in a clothes dryer. U.S. 4,692,277 discloses the use of 1,2-octanediol in liquid cleaners. See also U.S. Patents

3,591,510; 3,737,387; 3,764,544; 3,882,038; 3,907,496; 4,097,397; 4,102,824;

4,336,024; 4,606,842; 4,758,641; 4,797,310; 4,802,997; 4,943,392; 4,966,724;
4,983,317; 5,004,5~7; 5,062,973; 5,080,822; 5,173,200; EP 0 213 500; EP0 261 718; G.B. 1,397,475; WO 91/09104; WO 91/13145; WO 93/25654 and Hunt, D.G.
and N.H. Morris, "PnB and DPnB Glycol Ethers", HAPPI~ April 1989, pp. 78-82.
SIJ~IARY OF THE INVENTION
The present invention encomrAcsec a process for rleAning fabrics in a conv~nfior ~ tomAfic clothes dryer, comprising the steps of placing soiled fabrics in a flexible cc~ bag together with a rl~Aning composition, sealing said bag,placing said bag in the drum of the clothes dryer and ope,~Ling the dryer under convçntiQnAl usage con~itiQnc involving rotation of the dryer drum and the introduction of hot air into the drum, which co,ll~,lises the improvement wherein said bag is constructed of a polymer which is a ...~ nb-~ s~lected from the group conci~ g of nylon (~l efe. . ~,d) and polyester, and co- . .b; ~ ;onC thereof, whereby melting of said bag by the pr_se.~ce of ~ ed hot spots in said dryer is avoided.
In a p~ert;"~,d ~"o-,ess herein, a carrier is used to releasably contain the l~lFAI~ g co""~os;l;on. A pler~ d carrier herein CC~ll" lises a sheet of hydro. ~ gled fibers. Cell~llose sheets in the manner of disposable paper towels, and the like, can also be used as a carrier.
In anoll..,r pl~,f~ ,d aspect, the ~ F~;IW CC)~ )OS;l;OII used in the present invention CO--~ a .------hLr s~le~,~e;l from the group CQI~ . of methoxy-, ethoxy-, p-vpuAy- and butoxy-p-upo~y p-u~ ol. In yet a,~oLl,~r aspect, the ~ An;~g co~poS;~;on cv,..~";~s 1,2-v~ upA;c~l In a highly pl.,f~ d aspect, the II
CQ~pQ= l;l~n CO~ ;~S a n- ALur, of butoxy ~u~G~y propanol and 1,2-oct~n~;ol All p~ ~s, ratios and p,upc,lions herein are by weight, unless otherwise speçifi~A All dc.~ . n~ cited are, in rele~ part, inco".o~led herein by f.,f~,rellc_.
BRIEF DESCRIPTION QF THE DRAWINGS
Figure 1 is a p~ ye~lh~e of a ~ ";,~ sheet of the type used herein.
Figure 2 is a p~.~pe~ e of a cl~ sheet loosely resting on a co~
bag which is in a pre-folded con~itio~l Figure 3 is a pw ,~e-;Li~e of the sheet within the bag which is ready to receivethe fabrics to be dry cleaned in a hot air dryer.
DETAILED DESCRrPTION OF THE INVENTION
Con-~;t....~ Bag - The construction of the flexible bag used herein uses thermal resi~ L films to provide the needed t~,.,.p~,.àl~lre reCict~nre to internal self-sealing and external surface derul~alioll now found to be caused by overheated clothes dryers. In addition, the bags are resistant to the rh.omic~l agents used in the rl~s3ning compositions herein and subst~nti~lly imperrneable to their vapors and to water vapor. By proper selection of bag material, unacceptable results such as bag m~lting, melted holes in bags, and sealing of bag wall-to-wall are avoided. In ap.c~l-ed mode, the closure means for the bag is also constructed of a thermal t L~-l material.
The ~ ;ons of the co~ nt bag can vary, depending on the int~nded end-use. For example, a bag can be provided which is snffirient to contain one or two silk blouses. Alternatively, a bag suitable for h~n~ling a man's suit can beprovided. Typically, the bags herein will have an internal volume of from about 10,000 cm3 to about 25,000 cm3. Bags in this size range are s~ffiri~nt to ~ccc!.. ~rJId~te a re~eon~ le load of fabrics (e.g., 1-5 kg) without being so large as to block dryer vents.
The bag herein is p-~Ç~-~bly flexible, yet is plere.~bly durable enough to w;~ ml ' . Ic uses. Typically, such bags are p-~ ed from 0.0025 mm to 0.0075 mm (1-3 mil) ~ c~ c polymer sheets. If some rigidity in the bag is desired, somewhat thicker sheets can be used.
In a pl~ rt ...,d embodiment, 0.0025 mm to 0.0075 mm nylon film is sealed into a 26 inch (66 cm) x 30 in. (76 cm) bag in the manner shown in the Figures. Sealing is pr~.~ly done using a~andald implllee heating equipment. In an alternate mode, a sheet of nylon is simply folded in half and sealed along two of its edges. In yet anc,ll.er mode, bags can be made by air blowing operations.
tion to thermally stable Hnylon-only" bags, the co-.~ I bags herein can also be ~ pa.~.d using sheets of co-extruded nylon and/or polyester or nylonand/or polyester outer and/or inner layers surrounding a less thermally suitable inner core such as pol~ .ylene. In an alternate mode, a bag is constructed using a nonwoven outer "shellH co...~,. ;a;ng a heat-r~aial~-l material such as nylon orpol.~ lene Le.4ph~ and an inner sheet of a polymer which provides a vapor barrier. The non-woven outer shell prole_ls the bag from melting and provides animproved tactile i-..~ ;,;on to the user. Whatever the construction, the objective is to protect the bag's ;nleg.;ly under contlitionc of thermal stress at te..-pe.~ res up to at least about 400-500~F (204~C to 260~C).
Cleaning Compositions - The r,h~omir,~l compositions which are used to provide the r~le~ning filnction in the present process comprise ingredients which are safe and effective for their inten-led use. Since the process herein does not involve an ~lueo~c rinse step, the r~ ning compositions employ ingredients which do not leave u--de~ble residues on fabrics when employed in the manner ~~icciosed herein. While conventional laundry detergents are typically formnl~ted to provide good cle~ning on cotton and cotton/polyester blend fabrics, the cle~ning compositions herein must be form~ ted to also safely and effectively clean and refresh fabrics such as wool, silk, rayon, rayon acetate, and the like.
In addition, the cle~nin~ compositions herein comprise ingredients which are specially selecte~1 and forn~ tecl to ...;.-i.n;,~ dye removal from the fabrics being rle~n~ In this regard, it is recognized that the solvents typically used in i...n.e,~;on dry rl~nin~ processes can remove some portion of certain types of dyes from certain types of fabrics. However, such removal is tolerable in immersion processes since the dye is removed relatively uniformly across the surface of the fabric. In contrast, it has now been determined that high concel-l,alions of certain types of rle~ning ingredients at specific sites on fabric surfaces can result in unacceptable localized dye removal.
The plcrt:llt;d cle~nin~ compositions herein are form--l~ted to ..~ e or avoid this pre~'- n The dye removal attributes of the present cl~ g compositions can be co---pared with art-~licclosed cleaners using photographic or photo..,eL.ic measu.~,...,.lls, or by means of a simple, but effective, visual grading test. Numerical score units can be ~csignecl to assist in visual grading and to allow for st~tictic~l l. e~ of the data, if desired. Thus, in one such test, a colored g~ ...~,..l (typically, silk, which tends to be more susce~,Lil,le to dye loss than most woolen or rayonfabrics) is treated by p~ in~-on cleaner using an absG.l,e..L, white paper hand towel.
Hand p~ e is applied, and the ~mollnt of dye which is l-~"Ç~ ,d onto the white towel is ~esccd visually. Numerical units ranging from: (1) "I think I see a little dye on the toweln; (2) "I know I see some dye on the towel"; (3) I see a lot of dye on the towelH; through (4) "I know I see quite a lot of dye on the towel" are s-eCigT-~d by 1~ ~f ~
In ~ ifion to the Çc..~u...g conriderations, the ~ con~l-os;l;sn herein is prere.ably fo..~ d such that it is not so adhesive in nature that it renders thedevice unhandy or r1iffi~ult to use. However, and while not int~n-tin~ to be limiting of the present invention, the prerw-~d ~le~n;ng compositions ~ic~k!sed herein afford a spot-~ n;-~e process which is both effective and ~esthetic~lly p'~ - ~ when usedwith a device acco-~inl3 to this invention.
Having due regard to the foregoi..g conr;d~rations, the following illustrates the hl~die,llls used in the ele~ning compositions herein, but is not intpnr~ed to be limiting thereo~
(a) Solvent - The compositions will preferably co---~.;se at least about 4%, typically from about 5% to about 25%, by weight, of organic solvent. The objective is to provide at least about 0.4 g, preferably from about 0.5 g to about 2.5 g, of solvent per kg of fabrics being cle~nerl , (b) Fmllleifier - The compositions will comprise s--fficient Pmllleifi~r to provide a stable, homogeneous composition ~o~"~ ,i,-g cc""~onents f (a), (b) and (d). For the plerelled ~mlllcifi~rs disclosed hereina~ler, levels as low as 0.05%, preferably 0.07% to about 0.20%, by weight, are quite c~tief~ctory. If less P~rient ~om~leifi~ors are used, levels up to about 2%, by weight, can be used, but may leave some noticeable residues on the fabrics.
(c) Water -The compositions will COIll~liSe at least about 60%, typically from about 80% to about 95%, by weight, of water. Stated otherwise, the objective is to provide at least about 6 g of water per kg of fabrics being cl~nPd (d) Optionals - The compo,eitiQne herein may col--~.ise various optional in~tdie.,L~, inrlu~in~ perfumes, conventiQn~l surf~ct~nte, and the like.
If used, such optional ill~ d;e.llS will typically co"""ise from about 0.1% to about 10%, by weight, of the co,."~osi~ions, having due regard for residues on the cleaned fabrics.
It has now been de~tl~llhled that 1,2-oct~nPrliQl ("OD") affords special ad~t~,es in the formulation of the cl~p~ning compositio~e herein. From the ~l; n~ of ~P l~ c, OD is a relatively innocuol~e and low odor material.Mo.~,o~,., OD appears to vol~l;l; ~ from fabric surfaces without leaving visiblereQ;~ues This is PcpPri~lly illlpOl~ in a dry ,,l~ process of the present type which is con~Gtp~d without a rinse step. From the p~.rolll,ance ~l~"~poi-", OD
appears to r-n~l;O~ both as a solvent for greasy/oily stains and as what might be tenned a "pseudo-surfactant~ for particulate soils and water-soluble stains. Whatever the physical-~ l reason, OD has now been found to be a superior wetting agent with respect to both cle~ninc~ and ease-of-use in the present context of home-use 3 c~ os:l;onc and proc~s~s If used, OD will CollllJIi~ at least about 0.05%, typically from about 0.1% to about 1.5%, by weight of the c~ nin~
compositions herein.
A plert;.l~,d solvent herein is butoxy p-upo~y propanol (BPP) which is available in co.. ~ ,ial q~nl;l;fS as a ~fiA~ule of isomers in about equal amounts.
The isomers, and mixtures thereof, are useful herein. The isomer structures are as follows:

- CA 022283l0 l998-0l-30 n--C 4Hg--O--C H2C H2C H~O--C H2C H2C H2--O H

n--C4Hg--O--CH2 C--O--CH2CH2CH2- OH

n--C 4Hg--O--C H2C H2C H O--C H2 C--O H

BPP is on~ ng for cl~p~ning~ and is so effective that it allows the amount of the relatively eAI,~nsive 1,2-oct~ne~iiol to be ...;~ P~l Moreover, it allows for the formulation of effective clP~ning compositions herein without the use of convention~l surf~ ntc Importantly, the odor of BPP is of a degree and characterthat it can be relatively easily masked by conventional perfume ingl~di.,..Ls. While BPP is not cornplPtçly micr;ble with water and, hence, could negatively impact procPscing of the cl~n;~X co-,.l,os;l;onC herein, that potential p,.~'~ has been,.~cc~r.~lly o~e.~iu-lle by means of the PEMlJLEN-type polyacrylate Pm-llcifiP-s, as ~ ~licr,losed he~
The BPP solvent used herein is preferably a mixture of the af("t;~aid isomers.
In a pr~L -- d mode, the r1~n;.~g colllpos;l;onc COI~ e a mixture of the 1,2-o~ e~;9l and BPP, at a weight ratio of OD:BPP in the range of from about 1:250 to about 2:1, pref~,.ably from about 1:200 to about 1:5.
A highly pl~r~ ;d PmlllcifiPr herein is co....... ~ ,;ally available under the trademark PEMULEN, The B. F. Goodrich Company, and is des~,,il,.;d in U.S.
Patents 4,758,641 and 5,004,557, illcolyoral-~d herein by ~cr,.ence. PEMULEN
polymeric Pml~tCifiP~s are high ~'e lls~r weight polyacrylic acid po1ymers. The ~I,u-;lur~ of PEMULEN inrl~dPc a small portion that is oil-loving (lipophilic) and a large water-lo~ing (hydrophilic) portion. The structure allows PEMULEN to filn~ion as a primary oil-in-water em~llcifiPr. The lipophilic portion adsorbs at the oil-water interface, and the l~rLl-ophilic portion swells in the water forming a n~lwc,lk around the oil d-upl~,ls to provide emulsion stability. An hl-l,csll~ll advantage for the use of such polyacrylate Pm~lcifiPrs herein is that c~e~ning comrositiQnc can bepl ~ cd which contain solvents or levels of solvents that are otherwise not soluble or readily ble with water. A further advantage is that effective Pm-llcifir~ti~n can be ~cco~pliche~ using PEMULEN-type PmlllcifiPr at eAIl~,.llely low usage levels (0.05-0.2%), thereby ...;.-;...;,;-~g the level of any residue le~ on fabrics following product usage. For co.-.pa.ison, typically about 3-7% of conventional anionic ornonionic surf~rt~ntc are required to stabilize oil-in-water emlllcionc~ which increases the likelihood that a residue will be left on the fabrics. Another advantage is that Pmlllcifir~tion (proceccing) can be accomplished effectively at room te~ ela~lre.
While the clP~ning compositions herein function quite well with only the 1,2-oct~nP~iol, BPP, PEMULEN and water, they may also optionally contain detersive surf~rt~ntc to further enh~nce their rle~nin~ performance. While a wide variety of detersive surf~rf~nts such as the C12-C16 alkyl sulfates and alkylbenzene sulfonates, the C12-C16 ethoxylated (EO 0.5-10 avg.) alcohols, the C12-C14 N-methyl gl~c~mides, and the like can be used herein, it is highly plefe~,~d to use surfactants which provide high grease/oil removal. Tnrl-lded among such pleîwl~d surfactantsare the C12-C16 alkyl ethoxy sulfates (AES), especially in their m~gnPci-lm salt form, and the C12-C16 dimethyl amine oxides. Especially plc:fellt;d mixtures colll~lise MgAElS/MgAE6 sS/ C12 dimethyl amine oxide, at a weight ratio of about 1:1:1, and MgAEIS/C12 dimethyl amine oxide at a 2:1 weight ratio. If used, such surf~ct~nts will typically comprise from about 0.05% to about 2.5%, by weight, ofthe e~ning co,llpo~ ions herein.
In adtlitiQn to the p.-~"~d solvents and PrmllcifiPrs ~l;c~l~sed above, the g COlllpC5,:l;QnC herein may co",p,;s~ various optional in~di.;"L~., such as ,ru",es, preservatives, co-solvents, ~ e-~., salts for viscosity control, pH
tPrs or buffers, anti-static agents such as VERSAFLEX 157 or VERSAFLEX
2004 from National Starch Company, so~pnprs~ colorants, mothproofing agents, insect reppllpnt~ and the like. Enzymes such as proteases, lipases, amylases and.~Lu~s thereof can also be used at levels from about 0.0001% to about 1% of the co...l.os;l;o~1c The following illustrates pl~"~d ranges for clP~ning compositions for use herein, but is not intPnded to be limiting thereof.
Tn~ e d;~ % (wt.) Formula Range BPP* 5-25%
1,2-O,~ l o 1 7%
MgAElS 0.01-0.8%
MgAE6.5S 0.01-0.8%
C12 Dimethyl Arnine Oxide 0.01-0.8%
PEMULEN** 0.05-0.20%
Ethoxylated Alcohol*** 0.1-2.5%
Perfiume 0.01-1.5%
Water R~l~n-~e pH range from about 6 to about 8.
*Other solvents or co-solvents which can be used herein include various glycol ethers, inclu~ing materials marketed under trademarks such as Carbitol, methyl Carbitol, butyl Carbitol, propyl Carbitol, and hexyl Cellosolve, and especially methoxy pl ~,po,~y propanol (MPP), ethoxy propoxy propanol (EPP), propoxy propoxy propanol (PPP), and all isomers and mixtures, respectively, of MPP, EPP,and PPP, and the like, and mixtures thereof. Indeed, although somewhat less p,t;fc.l~d, the MPP, EPP and PPP, respectively, can replace the BPP solvent in the fc"~oh,g rkP~ning compositions. The levels of these solvents, and their ratios with 1,2-o~ AiQl~ are the same as with the prefel,~d BPP solvent. If desired, and having due regard for safety and odor for in-home use, various conventional chlorinated and hydrocarbon dry rlP~nin~ solvents may also be used. Tnrludpd among these are 1,2-dichlo,oclhane, trichloroethylene, isoyal~lns~ and mixtures thereof.
**As rlieclosed in U.S. Patents 4,758,641 and 5,004,557, such polyacrylates include homopolymers which may be crosslinL-ed to varying degrees, as well as non-crocelinl~ed Plefell~d herein are homopolymers having a molecular weight in the range offrom about 100,000 to about 10,000,000, preferably 200,000 to 5,000,000.***C12-C13 alcohol with about 6.5 EO's is p-t;Ç~ d; available as Neodol from Shell.
FYcr~llpnt clP~nin~ pelrulmancc is secured using any of the foregoillg non-.llm~ ;on processes and articles to provide from about 3 g to about 50 g of the rl ~ p CCilllyGS;liOnS per kg offabric being cie~ned Carrier - When used in a dry c1e~ning operation of the present type, the for~,going cle~ .g compositions are preferably used in col,lbinalion with a carrier, such that the rlP~ning co---pos;l;or- yelr~ll"s its function as the surfaces of the fabrics being cleaned come in contact with the surface of the carrier. The carrier releasahly C~ A;.~C the ~ A~ e composition By Hreleasably CC,..~ " means that the cl~ni~-g cc,lnyo~ilion is effectively ~eleased from the carrier onto the soiled fabrics as part of the dry ~IF~ . process herein.
The carrier can be in any desired form, such as powders, flakes, shreds, and the like. However, it will be appreciated that such co..~ ted carriers would have to be s~,pa ~Icd from the fabrics at the end of the ~le~ , process. Accol.lingly, it is highly pltife..~ d that the carrier be in the form of an integral pad or sheet which svbal~ ;Ally ,..~ ,;.,c its structural integrity throughout the ~lP~ning process. Such pads or sheets can be pl eyal ~,d, for example, using well-known metho<1e for m~n~f~ ing non-woven sheets, paper towels, fibrous batts, cores for b~n~ gPc diapers and c-~ ni~le and the like, using materials such as wood pulp, cotton, rayon, polyester fibers, and mixtures thereof. Woven cloth pads may also be used, but are not pr~,felled over non-woven pads due to cost considerations. Integral carrier pads or sheets may also be prt;pared from natural or synthetic syonges, foarns, and the like.

The carriers are designed to be safe and effective under the intended op~a~ing conditions of the present process. The carriers must not be fl~mm~hle during theprocess, nor should they deleteriously interact with the rle~ning composition or with the fabrics being cle~nPd In general, non-woven polyester-based pads or sheets are quite suitable for use as the carrier herein.
The carrier used herein is most preferably non-linting. By "non-linting" herein is meant a carrier which resists the ch~d~ing of visible fibers or microfibers onto the fabrics being cleaned, i.e., the deposition of what is known in common parlance as "lint". A carrier can easily and ~deq~-~t~ly be judged for its acceptability with respect to its non-linting qualities by rubbing it on a piece of dark blue woolen cloth and visually inspe.;li,lg the cloth for lint r~Q;d~es The non-linting qualities of sheet or pad carriers used herein can be achieved by several means, in~ in~ but not limited to: pl~palil,g the carrier from a single strand of fiber; employing known bonding te~hniqll~c collullol-ly used with nonwoven materials, e.g., point bonding, print bonding, adhesive/resin saturation bonding, adhesive/resin spray bonding, stitch bonding and bonding with binder fibers. In an alternate mode, a carrier can be pre~,ared using an abso,l,e.,l core, said core being made from a material which, itself, sheds lint. The eore is then enveloped within a sheet of porous, non-linting material having a pore size which allows passage of the P CO,--i o~:';onc~ but Ihluugh which lint from the core cannot pass. An ~Y~mrle of such a carrier co".l"ises a c~ lQse or polyester fiber core enveloped in a non-woven polyester serim.
The earrier should be of a size which provides s~ffiri~nt surface area that effeetive contaet bet veen the surface of the carrier and the surface of the fabrics being eleaned is aehieved. Of eourse, the size of the earrier should not be so large as to be u.~han~ for the user. Typieally, the d;-~ cnc of the carrier vill be s~ffirient to provide a ,-~-oscopic surface area (both sides of the carrier) of at least about 360 em2, ~ r~ in the range from about 360 em2 to about 3000 em2. For , a l~c~ earrier may have the rlim~nQi~c (X-dile_liol~) of from about 20 em to about 35 em, and (Y-direetion) of from about 18 em to about 45 cm.
The carrier is intended to contain a snffirient amount of the rle~nin~
cQmrositiQr to be effective for its intenrled purpose. The capacity of the carrier for the cle---;ng c~---pos;l;ol- will vary acco,-li-,g to the intPnded usage. For ~y~mrlp carrier/rle~ning co...l,osilion pads or sheets which are int~nded for a single use will require less capacity than such pads or sheets which are intended for mllltirle uses.
For a given type of carrier the capacity for the rle~ning composition will vary mainly with the thirl-n~cc or "caliper" (Z-direction; dry basis) of the sheet or pad. For WO 97/07278 PCT~US96/12976 purposes of illustration, typical single-use polyester sheets used herein will have a thirl~nese in the range from about 0.1 mm to about 0.7 rnm and a basis weight in the range from about 30g/m2 to about 100g/m2. Typical multi-use polyester pads herein will have a thir~n~cs in the range from about 0.2 mm to about 1.0 mm and a basis weight in the range from about 40 glm2 to about 150 g/m2. Open-cell spongesheets will range in thiCl~n~C~ from about 0.1 mm to about 1.0 mrn. Of course, the fore~oing ~limPn~ionc may vary, as long as the desired quantity of the c~ ning composition is effectively provided by means of the carrier.
The p~cÇellcd carrier herein comprises a binderless (or optional low binder), hydro~nf~led absoll,~nt material, especially a material which is form~ ted from a blend of cellulosic, rayon, polyester and optional bicomponent fibers. Such materials are available from Dexter, Non-Wovens Division, The Dexter Col ,uo, alion as HYDRASPUN~, especi~lly Grade 10244. The m~mlf~ctl-re of such materials forms no part of this invention and is already ~licclose(l in the literature. See, for ~Y~mrl~
U.S. Patents 5,009,747, Vi,.,.-.el~Ly, et al., April 23, 1991 and 5,292,581, Vi~ y, et al., March 8, 1994, incorporated herein by ler~ ce. P~eréll~,d materials for use herein have the following physical pl upel lies.
Grade Optional 10244 Targets Ran~e Basis Weight gmlm2 55 35-7S
Th~ n~ss ~If.~,~ unS 355 100- 1500 Density gm/cc 0.155 0.1-0.25 Dry Tensile gm/25 mm Wet Tensile gm/25 mm MD* 700 200-1250 CD* 300 100-500 Bligl.~ 5S % 80 60-90 Absol~,lioll Capacity % 735 400-900 (H2O) Dry Mullen gm/cm2 1050 700-1200 t *MD - m~rhine direction; CD - cross direction As ~l;c- 1osed in U.S. 5,009,747 and 5,292,281, the h~.lr~e~ gl;-.~ process provides a nonwoven material which CO~ ,liSeS c~ ocic fibers, and pl'è~el~bly atleast about ~% by weight of synthetic fibers, and requires less than 2% wet strength agent to achieve improved wet ~LI.,nglil and wet toughn~ss W O 97/07278 PCTrUS96/12976 Surprisingly, this hydroentangled carrier is not merely a passive absorbent for the rl~ning compositions herein, but actually opLi~ es~le~ning performance. While not intPntling to be limited by theory, it may be specul~ted that this carrier is more effective in delivering the cle~nin composition to soiled fabrics. Or, this particular carrier might be better for removing soils by contact with the soiled fabrics, due to its ..~lu.e of fibers. Whatever the reason, improved dry ~le~ning pt~ru~ lce iS
secured.
In addition to the improved cleaning pe.rullllallce, it has now been discovered that this hydroPnt~nglP,d carrier material provides an additional, unexpected benefit due to its resiliency. In-use, the dry cle~ning sheets herein are dPsigned to function in a s~lb~ ly open confi~ration. However, the sheets are packaged and sold to the conC~mPr in a folded configuration. It has been discovered that carrier sheets made from convpntion~l materials tend to undesirably revert to their folded configuration in-use. This unde~..~le attribute can be ove~col.lc by pc.rc,l~;ng such sheet, but this r~lu~ an ~drlition~l processing step. It has now been discovered that the hyd.o~ .glPd materials used to form the carrier sheet herein do not tend to re-fold during use, and thus do not require such pe-ru-~lions (~Itho--gh, of course, p~lru~Lions may be used, if desired). Acco,~ ly, this newly-discovered and ~ led all~ilJule ofthe carrier materials herein makes them optimal for use in the manner of the present invention.
Process - The present Cl~ning process using the thermally stable CQ~
bag is condl~ pd in a l~ h!;~g app~al-ls in the plese.lce of heat. In a convenient mode a co~ f- bag with the carrier/rle~ning composition and env~lG~,ing the soiled fabric is sealed and placed in the drum of an ~tom~tic hot air clothes dryer. The drum is allowed to revolve, which imparts a tumbling action to the bag and ~g~t~tion of its co~ ; com,u"~ ly with the tumblin~ By virtue of this ~glt~tion, the fabrics come in contact. with the carrier CQ~ the clP~ning cGIn~osilion. The tllmhling and heating are carried out for a period of at least about 10 ...;....lee, typically from about 20 mimlt~PS to about 30 minlltes The process can be conAucted for longer or shorter periods, dc~ g on such factors as the degree and type of soiling of the fabrics, the nature of the soils, the nature of the fabrics, the fabric load, the amount of heat applied, and the like, according to the needs of the user.
EXAMPLE I
A dry C~ ning article in sheet form is asselllbled using a sheet substrate and aclP~ning co,n~,os;~ion plepared by ~mixing the following ingredients.
In~l~die,ll % (wt.) BPP* 7 0 1 ,2-octanediol o.5 PEMULEN TR-l** 0.125 KOH 0.08 Perfume 0.75 Water and minors*** R~l~nce *Isomer mixture, available from Dow Ch~omir~l Co.
**PEMULEN TR-2, B. F. Goodrich, may be s~bstit~lte~
***Tn~ des preservatives such as KATHON~.
A non-linting carrier sheet is prepared using stock HYDRASPUN~ Grade 10244 fabric, described above. The fabric is cut into square carrier sheets, ap~lo,c;~ lely 9 in (22.9 cm) x 10 in (25.4 cm), i.e., 580.6 cm2 sheets.
23 Grams of the above-noted r le~ning composition are evenly applied to the sheet by spreading onto the sheet with a roller or spatula using hand pressure. In an alternate mode, the çl~nin~ composition can be applied by dipping or spraying the CO~ O~;Qn onto the substrate, followed by sq~le~7ing with a roller or pair of nip rollers, i.e., by "dip-squee7in~ll or "spray sq~le~ ". The external surfaces of the sheet are damp but not tacky to the touch. The finiched sheet can be folded for p~ ing, and when unfolded and used in the manner di~rlosecl herein, the sheet renla"ls in the desired unfolded configuration.
EXAMPLE II
The following illustrates a typical process herein using the CG.. l~i.. l bag herein, but is not ;.~ ed to be limiti~ thereof.
As shown in Figure 2, a flat sheet (2) of flexible nylon polymer with a patch ofVelcro~Ltype f~cten~r (3) is aaa~;lllbl - ~ In an alternate mode, a nylon zipper or Zip-Lok~ type dosure means as well as contact adhesive or simple ties can be used. Aco.~ F--l bag is formed by folding the sheet and bondi,lg along border (4). As shown in Figure 3, closure flap (5) with sealing means (3) allows closing and sealing ofthe bag by ullposhlg sealing means (3) onto contact surface (6). In a typical mode, a sheet (1) of the type described in F~ . 'e I is placed in the plastic bag having a volume of about 25,000 cm3, as shown in Figure 3. Up to about 2 kg of dry ga l"eula to be cleaned are then placed in the bag. When the g~llle.lLs and the dry ~1~AI~ g sheet are placed in the bag, the air is prel~,ably not squeezed out ofthe bag before closing and sealing. This allows the bag to billow, thereby providing sl~ffi~ient J space for the fabrics and rle~ning sheet to tumble freely together. The bag is then closed, sealed and placed in a convention~l hot-air clothes dryer. The dryer is started and the bag is ~ e~ for a period of 20-30 mim-t~s at a dryer air t~""~e,all-re in the range from about 50~C to about 400~C. During this time, the sheet comes into close W O 97/07278 PCT/US96/1~976 contact with the fabrics. After the m~chine cycle is complete, the bag and its contents are removed from the dryer, and the spent dry cleaning sheet is discarded. The nylon bag is retained for re-use. The bag retains its integrity even at the highest temperatures in the range and can be re-used 5-10 times, or more. The fabrics are cleaned and refreshed. The water present in the cleaning composition serves tO
wrinkles in the fabrics.
In an alternate mode, heavily soiled areas of the fabric being cleaned can optionally be pre-treated by pressing or rubbing a fresh dry cl~ning sheet accord.l~
to this invention on the area. The sheet and pre-treated fabric are then placed in the nylon bag, and the dry rie~ning process is con~ cted in the manner described herein.
EXAMPLE III
The following illustrates a typical dry cle~ning kit herein, but is not inttonrled to be limiting thereo~
A dry ~k~ning kit is ~csembled pa~ ging multiple (typically, 5-10) single use dry cle--~ g sheets of the type described herein together with a sealable, reusable nylon conlS~in~r bag, in a pac~ e Cc~ Jl;s;llg a convention~l c~rdboard box suitable for retail sales.
EXAMPLE IV
A dry cle~nin~E~ composition with reduced t~ndenry to cause dye ''blee~iin~ll orremoval from fabrics as tiicclosed above is as follows.
INGREDIENT PERCENT (wt.) (RANGE) Bulu~y~ o~ypropanol (BPP) 7.000 4.0 - 25.0%
NEODOL 23 - 6.5* 0.750 0.05 - 2.5%
1,2-O~;l; nf~Ji~l 0.500 0.1 - 10.0%
r~.rulll~ 0.750 0.1-2.0%
PemulenTR-l 0.125 0.05 - 0.2%
p~JtA~ IIydlu~de (KOH) 0.060 0.024 - 0.10 PulAc~ Chloride 0.075 0.02 - 0.20 Water (rliCtillPd ordf ~ni~p~d) 90.740 60.0- 95.0%
Target pH = 7.0 *Shell; C12-C13 ~ hol~ ethoxylated with average EO of 6.5.
15-25 Grams of a composition of the foregoing type are placed on a HYDRASPUN~ carrier sheet for use in the manner tlicclc!sed herein.
R~Q;deS the optional nonionic surf~ct~ntc used in the cleaning compositions herein, which are pl e rel ably Cg-C 18 ethoxylated (E01 - 15) alcohols or the coll.~lJor~ g ethoxylated alkyl ph~nolc, the compositions can contain t;l~ylllcS to CA 022283l0 l998-0l-30 further enh~nce cle~ning performance. r iraees~ amylases and protease enzymes, or mixtures thereof, can be used. If used, such enzymes will typically comprise from about 0.001% to about 5%, preferably from about 0.01% to about 1%, by weight, ofthe composition. Commercial detersive enzymes such as LIPOLASE, ESPERASE, ALCALASE, SAVINASE and TERMAMYL (all ex. NOVO) and MAXATASE and RAPIDASE (ex. Intern~tion~l Bio-Synthesis, Inc.) can be used.
If an ~ntiet~tic benefit is desired, the compositions used herein can contain ananti-static agent. If used, such anti-static agents will typically comprise at least about 0.5%, typically from about 2% to about ~%, by weight, of the compo~iti~ne F'léÇ~ ed anti-stats include the series of sulfonated polymers available as VERSAFLEX 157, 207, 1001, 2004 and 7000, from National Starch and Chemical Company.
The compositions herein can optionally be stabilized for storage using conventinn~l preservatives such as KATHON~ at a level of 0.001%-1%, by weight.
If the compositions herein are used in a spot-~ mode, they are Çel~bly pressed (not rubbed) onto the fabric at the spotted area using an applicator pad CO,l",li~l.lg looped fibers, such as is available as APLIX 200 or 960 Uncut Loop, from Aplix, Inc., Charlotte,.NC. An underlying absoll,~,.lL sheet or pad of looped fibers can optionally be placed beneath the fabric in this mode of operation.

Claims (7)

1. In a process for cleaning fabrics in a conventional automatic clothes dryer, comprising the steps of placing soiled fabrics in a flexible containment bag together with a cleaning composition, sealing said bag, placing said bag in the drum of the clothes dryer and operating the dryer under conventional usage conditionsinvolving rotation of the dryer drum and the introduction of hot air into the drum, the improvement wherein said bag is constructed of a polymer which is a member selected from the group consisting of nylon, polyester, and combinations thereof, whereby melting of said bag by the presence of unanticipated hot spots in said dryer is avoided.

2. A process according to Claim 1 wherein a carrier releasably contains the cleaning composition.

3. A process according to Claim 2 wherein the carrier comprises a sheet of hydroentangled fibers.

4. A process according to Claim 1 wherein the cleaning composition comprises a member selected from the group consisting of methoxy-, ethoxy-, propoxy- and butoxy-propoxy propanol.

5. A process according to Claim 1 wherein the cleaning composition comprises 1,2-octanediol.

6. A process according to Claim 1 wherein the cleaning composition comprises a mixture of butoxy propoxy propanol and 1,2-octanediol.

7. A process according to Claim 6 wherein the bag is nylon.