US2916037A - Disposable diaper - Google Patents

Description

Dec. 8, 1959 G. c. HANSEN DISPOSABLE DIAPER Filed Nov. 19, 1956 IN V EN TOR.

650865 6! H)? ,vs EM BY M024. MEN 4-411 Arraensv:

Statcs Patent ill Application November 19, 1956, Serial No. 622,869

2 Claims. (Cl. 128-284) This invention relates to a disposable diaper.

. vInits preferred embodiment as herein disclosed, the daiper con'lpr'isesfan inner pad of partly refined pulp which' h'as been stabilized by spraying with adhesive. The stabilization of a pulp pad in this manner is not herein claimed, comprising the subject matter of a separate application. v

The partial refinement of the pulp has to do with the degree to which its fibers have been separated. In the original .wood, the fibers are, of course, bonded together. In the pumping operation, the fibers are torn apart and the bonding agent present in the growing timber is eliminated. Nevertheless, considerable adhesion between individual fibers remains and in the refining operations these are mechanically separated by known procedures. The; present: invention requires that the refining operation; be stopped at an intermediate point. If the refining is-insufficient, the pulp will be coarse and harsh to the touch. If the refining is carried to a maximum degree, the fibers will not only be separated but broken up to such a point that the resulting pulp pad will have the action of a wick and tend to disseminate rather than to retain the liquids it is designed to catch and hold.

The refined pulp is formed into a batt by procedures forming no part of the present invention and this batt is first sprayed wtih a sizing adhesive and is then laminated to backing and facing plies, both of which are porous or absorbent, the preferred difference lying in the fact that the facing ply is desirably a non-woven fabric and the backing ply a porous wet strength paper. One or more plies of absorbent paper may be placed between the basic facing ply and the pulp pad to eifect dispersion of liquids and to render the pad softer by preventing pulp fibers from protruding through the facing ply. A wide variety of adhesives may be used for sizing, including dextrin, starch, resin or latex in any liquid vehicle suspension. The amount of dilute adhesive used may vary from one to five grams per diaper of seven inches by sixteen inches and the degree of concentration is indicated by the fact that this will ordinarily represent a raneg of seven-tenths of a gram to 1.5 grams of adhesive solids per diaper. Products of other dimensions would, of course, be treated proportionately.

In the assembly of the product, the facing web and the web or webs of underlying tissue, if any, are fed beneath the advancing web of pulp, one or both surfaces of which have been freshly sprayed with sizing. The rear face of the web of pulp is always sized. When the front face of the pulp web is sized, underlying tissues will always be employed. The facing web is made materially wider than the web of sized pulp and the margins of the facing web are turned over onto the exposed face of the pulp and subjected to the action of gluing rolls after which the backing web is applied and subjected to pressure to bond it securely to the inturned margins of the facing web.

Finally, the resulting laminated web is cut into individual diaper lengths and the end margins of the individual diapers are subjected to heavy sealing pressure. Undoubtedly, the seal is partially attributable to the still adhesive surfaces of the fiber of the pad, but it is believed that the embossing pressure exerted thereon is primarily responsible for closing the ends of the diaper and interlocking the fibers of the pad with each other and with the backing and facing sheets. It is considered very desirable that the pulp'extend to the end of the pad to intervene between the facing and backing sheets at all points, clear to the ends of the diaper.

In use, the diaper is desirably held to the childs body by some means other than itself. It can, for example, be supported by a conventional cloth diaper. Desirably, the diaper of the present invention is used as an insert in a specially designed, moisture-proof garment which is here illustrated but is not claimed herein, since it forms the subject matter of another application.

In the drawings:

Fig. 1 is a view in perspective of a complete diaper embodying the present invention, portions thereof being broken away to expose interior plies.

Fig. 2 is a view in cross section through the diaper shown in Fig. 1.

Fig. 3 is an enlarged fragmentary detail view of an end portion of the diaper in inverted plan.

Fig. 4 is a detail view on a further enlarged scale taken on line 4-4 of Fig. 3.

Fig. 5 is a view in perspective showing the diaper of the present invention introduced into the garment for purposes of application to a child.

Fig. 6 is a diagrammatic view in longitudinal section showing, merely by may of exemplification, a series of procedural steps in the production of the diaper of the present invention.

As already indicated, the preferred practice involves use of a non-woven fabric for the facing ply 1 which represents the top surface of my improved diaper. Beneath this there is optionally incorporated one or more plies 2 of absorbent paper tissue of the grade of facial tissue or the like.

The center of the diaper comprises a pad 3 of partially refined pulp stabilized or bonded by minute quantities of adhesive which connect its fibers at innumerable points, the adhesive being used so sparingly that it does not stiffen the pulp pad.

The bottom of the pad comprises a backing ply 4 of paper of high wet strength but nevertheless porous. The diaper is made relatively thin. For some babies, a single diaper of this weight is ample. However, it is an important feature of the present diaper that the backing sheet as well as the facing sheet be porous and permeable so that, when a plurality of diapers are used simultaneously, liquid will pass from one to another to neutralize the absorbent capacity of them all.

The width of the facing ply 1 preferably exceeds the,

Width of the pulp pad 3 sufficiently to permit the side margins 5 of the facing ply to be turned over the edges of the pad and to receive bonded connection with the backing ply 4 which is held thereto by an intervening strip of adhesive shown at 6 in Fig. 2.

The pulp pad 3 projects to the end of the diaper as shown at 7 in Fig. 4. At its ends, the diaper is of considerably reduced thickness by reason of embossing 8 (Fig. 3) which actually unites the fibers, as is well known in the paper converting field. The adhesive size with which the fibers of the pad 3 have been sprayed will bond the backing ply 4 to pad 3 and will also assist in closing the ends. When sizing is sprayed on the front of the batt, it will bond the pad 3 to the tissue. The intermittent and/or adhesive connection of the several plies as a result of the embossing operation at the ends of the diaper desirably stiffens these ends, this being advantageous in holding the diaper securely inposi-tion in such a a gannent asthat'shown' in Fig. 5.

""In' use, the end'porti'ons' of the resulting diaper, ge-' nerically designated by reference character 10 in Fig. 5, are inserted-beneath,the. overhanging web portions 11 of al garment lz which has'las'tic' sid nap'satziataad 14' and glove fasteners or .other'connecting inea iislwhereiby. the 7 side flaps may be connected toie achlother and to the upwardly'folded endporti'ns 15." ,Eurth eii 'dfltails' of; this garment are ,notrequired, 'sincegit jfiorrns no; part bftjhelpresentinvention'j It is de'sire'dto'nQteZOHIY that it. is desirably made oflwaterproof but'fflexible'ln'iaterial and has a largeopening 16 through which most of the upper surface of the diaper is exposed toIreceiye bodily excretions from the child wearing the garment.

Thefidiaperisusufliciently flexible] sotthatl jti is ,readily 'manipulated into place-through this opening and iswithdrawable with equal facility for disposal. The, stiffness l. tweb: Zahare turned bytgonyentionaliiorniers indie about the edges of the pulp in the manner already dis- 7 sure of sealing rolls 32 and 33.-

t fabric facing ply overlying the'fro'nffa'ce of thebattand ,of the embossed diaper ends helps torhlold thefdiape'r'tflat t and in place. a The entire diaper isdesir'ab-ly made of pad and tissue materials capable of disintegrationin water to the diagrammatic disclosure in this view is solelyby way of exemplification. It does not represent. the only'way in which the diaper can be manufactured. X

From the parent roll 18 of pulp, the pulp web..19 passes betweentupper and lower'spray 'ndzzles20;and 21, nozzle 20 spraying adhesive sizing upon thefupper surface of web 19 (as viewed in Figure 6) and, if:desired, nozzle 21 spraying adhesive'sizigg on:the.. lower surface. r t v V Beneath the path of .the' pulp webt are supply rolls 22 and 23 from which the webs 24 of top/facing material a p p 7 n p and.,25 .oftissue materialpass into lamination .wit-h'the As shown at 34 and 35, conventional cutting and embossing dies sever the individual diapers and seal their l ends in the manner above'idesci'ib'ed.

1. A multi-ply'diaperfor use as aninsert in a garment diaper holder ctimprisinghbattbf paztially frefined pulp, the back of rsaidt b l bsin si ssl RQB rpm-wov n having marginsoverturnedzpntolnthehacl of the batt, a

porous wet strength paper backing ply secured to the batt;

by the said sizing and adhesively secured to the margins of the facing ply, said batt extending to both ends of the diaper dcthe-en vqi t aperrbsia cl stifi- .c ne -by b in Q QP SQ -f a 2 m t -p y di pe fqrfus fas riserd 'ape ho d r c mpris ng a but at Pat a the b clsof sa d-b it ie n fiize pawns ab f ng p ytQ erllip et cntlf s fj having margins overturned onto the ba'clg' po w strength Pap r l ls u nly seen w h: d z n ian esi e Yurjeid to a a th a n p y, i tbat e ten 11 toiboth'e lc g diaperand th end ft e perbq n closed-a ened by embossing. V V

4 References Cited in the' fil'e of fthis patent I UNITED STATES PATENTS. r t

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