US2973760A - Sanitary napkin - Google Patents

Description

March 7, 1961 DUDLEY 2,973,760

SANITARY NAPKIN Filed June 30, 1958 4 Sheets-Sheet 1 INVENTOR. 1 /z, 419rq 01/015) j "ylj. @Q RM,

ATIZWA/EX March 7, 1961 E. DUDLEY SANITARY NAPKIN 4 Sheets-Sheet 2 Filed June 30, 1958 -x v V X? mm E mm M H MQ w W \0 H m EM M Z w .NN 2% \w w R NW kw MM E. DUDLEY SANITARY NAPKIN March 7, 1961 Filed June 30, 1958 A TTOAIVEK March 7, 1961 E. DUDLEY 2,973,760

SANITARY NAPKIN Filed June 30, 1958 4 Sheets-Sheet 4 571g INVENTOR.

51/2455 DQDZEY B Paper Company, Chester, Pa., a corporation of Pennsylvania Filed June so, 1958, Ser. No. 745,544 2 Claims. (01; 128-287) The present invention relatesto catarnenial devices" and particularly to that type which is a sanitary napkin in pad form rather than in tampon form.

'One'obj ect of the pr'esent invention is to provide a new and difierent pad type of sanitary napkin.

'Another object of this invention is to provide a sanitary napkin pad which conforms to the female anatomy to provide more comfort and utility.

Another object of the invention is to provide a napkin that will not slip out of place While worn. v

A further object of the invention is to provide anapkin which will give the user security against strike through to the underside of the pad while in use. a

Aniadditional object of the invention is to provide a sanitary pad that will not fold, distort or collapse in use.

Another object of the invention is to provide a sanitary Another object of the present invention is to provide'a sanitary napkin which will remain firm without bunching when worn.

Another object of WOT I1.

appended'specification', claimsand-i drawings.

Gatamenialrdevices, have long been known and butit is a relatively short time ago that the sanitary napkin which. is .jin general use today was developed; The disposable sanitary napkin of the pad type,- which-is the; mo st popular type,, was, first marketed; some time:

the present, invention is to provide a sanitary napkin which'is substantially invisible when Furtherobjects will be apparent by reference: to the rent used o Ice vices a'nd' can be manufactured rapidly and at low cost with relativelyinexpensive machinery. V

,Fofr the purpose of illustrating the invention, there are shown in the accompanying drawings forms thereof which are at present preferred, although it is to be understood that thevarious instrumentalities of which the invention consists can be variously arranged and organized and that the invention is not limited to the precise arrangements and organizations of the instrumentalities as herein shownand described.

In vthe drawings, wherein like reference characters indicate like parts: V

Figure 1 is a side elevational view illustrating the sanitary napkin of the present invention as it may appear when supported by a'belt;

Figure 2 is a perspective view of the sanitary napkin of thepresent invention disposed in a generally curved shape which illustrates theconformation of the napkin as it is worn.

Figure 3 represents a vertical cross-sectional view taken generally along line 3--3 of FigureZ and, without showing the details of construction, illustrating the generaloutlirie of the'napkin as worn.

Figure 4 is a vertical cross-sectional view taken-along line 44 of Figure 9lwith the component parts disposed in extended position more clearly to illustrate the relationship of the components.

Figure 5 is a vertical c'ross sectional view, similar to Figure '4 but showing another embodiment of the present invention. p 1

Figure -6 is a perspective view of the napkin of Figure 4 showing the component parts as they might be assembled and with the cover or envelope illustrated by dashdot lines.

Figure 7 is a perspective view similar to'Figure 6 illus-- Figures 3, 8 and 9; it is to: be noted that. the napkin of the present invention has side edges 15 and 16 which are afllfthoitlln of the; century. -'1fhese disposable-sani-w tary napkinsare usually, made of highly absorbent'cellulose; material generally rectangular in shape and rela 1 tively wide and also relatively thin in cross section and;

can, be produced on, high speed machinery capable :inexpensively of; fabricating-large quantities of such nap.-= kins. However, i fold; and distort is thatthey are P il?) being re l ati semipermeable through? in u has beenobSerVedthat these padsoftena use; with consequent bunching. anddiscomfort and 1 CSS" o f;- efliCieIlcy-- The reason. for this dapted to the female anatomy. Such.

to. i e-- g of clothing ri '1. t. i- A r I m and varied forms of sanitary napkins to" ovier'cometiiis' "probleiin but the capital equipment neces sar'y to manufacture sanitary napkins is'expensive. and

not readily changed to make new types. Moreover, it

is only recently that tlie lsanitarynapkin manufacturer's-v have beenin' a position to advertise thein product in the popular press and magazines and therefore'the successn'ot'parallel to 'forrn a pad. which isa truncated triangle or elongated trapezoid. This is clearly shown in Figure's 8 and 9'. Furthermore, the napkin is formed so that it does'not collapse or bunch and the vertical cross-'- or bunchirig of the napkin into the desired shape while it is beingjwor n. jAsl mentioned above, sanitary napkins of the past have b een relatively wide and flat, with generally parallel sideedges. Such napkins didnot conform to; the shape of thefemale anatomy and, when worn, were .Of necessity compressed or; bunched together be tweenzthe legs; in; the anal region, and were uncomfortable,

and in many cases were used in a manner not con- The structure of the napkin which accomplishes this end is illustrated more particularly in Figures 4 to 7 inclusive:

That embodiment of the napkin which is illustrated in Figure 4 includes an outer cover 21 which may be of gauze, non-woven fabric or a similar type of reinforced absorbent material. This cover 21 is primarily an envelope for retaining the component parts of the napkin therein but is also used as the means of securing the napkin in place to a belt 27, as illustrated in Figure 1, and hence must be relatively strong and have sufficient tensile strength to withstand the rigors of normal use. a

The napkin of the present invention also includes an impervious generally central or medial strip 22 which extends fully from side to side and from end to end as shown clearly in Figures 6 and 7. This strip 22 is a fluid barrier and may consist of a thin sheet of polyethylene or a thin sheet of paper having a polyethylene coating thereon. Thus the barrier 22 effectively divides the napkin into two separate areas, one on each side of the medial strip and each of which area is adequate, in terms of its absorptive capacity and volume satisfactorily to provide the protective services required of a sanitary napkin.

Referring to Figure 4, the napkin on each side of the barrier 22 consists of a generally central portion 23 or 23-11 composed of an absorbent material called fluff which is made by grinding highly purified wood cellulose in a hammer :mill and forming a batt of the resultant product. Such material has capacity to retain large volumes of fluid and provides necessary bulk and volume. It is preferred that one of such batts 23-0 be shorter in length than the other 23, so that the vertical dimension of the napkin may taper toward its ends, as illustrated in Figures 1, 6 and 10. Although such tapering is not essential to the function of the napkin it is desirable from a comfort standpoint and also so as to render the napkin generally inconspicuous when worn.

On each side of each of the batts 23 and 23-a there are disposed a number of layers of creped wadding 24.

Creped wadding is generally understood in the papermaking art to mean a sheet of tissue'paper creped, when dry,

on a so-called Yankee Dryer and generally such creped wadding has a basis weight of from 8' to 15 pounds per ream and a stretch value exceeding 10%. It is made from highly purified cellulose fiber and is extremely absorbent while yet possessing certain 'capillarity or directional characteristics and strength whichassist' in the rapid distribution of the menstrual fluid to the absorbent portions of the napkin on the same side of the barrier 22. This characteristic is particularly desirable in the .early stages of menstrual flow where the volume of fluid may be quite high and the need arises for effective absorptive use of all portions of the napkin on the side nearest the body of the wearer.

It can be understood by referring to Figures 6 and 7 that each napkin of the present invention'is, in reality, a double faced napkin with the absorptive portions on each side of the medial strip 22 efiectively functioning as a single napkin and of sufficient capacity to handle necessary fluid discharge. a a

More importantly, however, the composition of the pad provides a structure which is two sided and hence the pad may be worn with either of the two major surfaces facing inwardly. The barrier strip 22, which is as wide and as long as the widest and longest dimensions of the pad, and hence has its edges coextensive with the outer edges of the pad, as shown clearly in Figures 6 and 7 affords complete protection against strike-through and the two-sided construction of the napkin makes it unneces sary to identify one or the other of the two sides as being the'side which should be disposed against the body since either side may be Worn in contact with the body.

Still more importantly, the side of the napkin which does not directly receive the menstrual discharge and hence does not collapse because of being softened by the menstrual fluid operates as a supporting means and shaperetaining means, as is more clearly illustrated in Figures 2, 3 and 8. It has been found to be psychologically important from the standpoint of feel and appearance as well as structurally necessary, utility wise, to provide a pad which affords adequate bulk and capacity and the napkin of the present invention provides these features even though at first glance it appears substantially narrower than the napkins of the past. The napkin of the present invention is pre-formed to conform to the female anatomy and is constructed, in such shape, to provide adequate absorptive and protective characteristics. Therefore, the pad may be somewhat less flexible than prior pads because its shape is correct and it does not become compacted in the anal region where protection is not an issue as do the thin, wide napkins of the prior art. Thus the present napkin functions properly without distortion. The portion of the napkin not receiving the fluid below the barrier 22 remains dry and retains its original shape, as shown in Figure 3, while yet permitting the upper portion to follow the contours of the famale anatomy as shown in Figures 1, 2 and 3. The lower portion of the napkin which is shielded from overflow of menstrual fluid by the barrier 22 retains its generally trapezoidal shape and supports the barrier strip 22 in proper position where it functions to protect the clothing of the wearer.

It will be noted from the foregoing that the napkin, though generally narrower, is appreciably thicker than the napkins of the prior art, thus providing a structure which has adequate absorptive capacity on either side of the barrier strip while also insuring that the napkin will fit properly and comfortably without distortion or compacting. In fact, the napkin, because of its shape and size, conforms to body contours and does not move out of place when worn. Although, by way of illustration, the napkins, as manufactured, are generally 1% inches thick at the central portion, material settling or compacting during shipment may change this dimension somewhat. However, the average napkin, prior to use, and hence in its unused state, will provide an absorbent structure havmg, at a density of approximately .035 gram per cubic centimeter of volume, a total weight of approximately 10 grams, exclusive of the cover.

Further, by way of illustration, the napkin of the present invention may be about 2%. inches wide at the front and about 1 /3 inches wide at the rear portion, and about 8inches long. It will also be noted from Figures 1 and 2 that the napkin is intended to be worn with the wider portion toward the front and at a slightly higher elevation than the narrower terminal portion. This insures a more comfortable napkin and places the absorptive portions in a position more adequately to receive the menstrual fluid .and eliminating unnecessary, uncomfortable and unused material near the rectal opening.

With reference to Figures 9 and 10 it can be seen that the frontal portion 25 of the cover 21 is somewhat shorter than the rearward portion 26 of the same cover. When such terminal portions 25 and 26 are affixed to the supsecure retainer for the absorbent portions of the pad.

In the embodiment illustrated in Figures 5 and 7 the I medial strip 22 is still centrally disposed within the cover 21 and substantially equal amounts of absorptive material are disposed on each side of the medial strip. However, in this embodiment, the fluff is disposed in four separate batts, with somewhat thinner batts 28a and 28 on one side of the strip 22 and batts 28-0 and ZS-d on the other side of the barrier. Layers of creped wadding 29-a separate the batt 28-a from the cover and, similarly, layers of creped wadding zi -b separate the batt 28-d from thecover 21. Layers of creped wadding Sit-a and w-b separate the batts 28-a and 28-19 and the batts 23-0 and 23-a' respectively.

The absorptive capacity of the napkin shown in Figure 4 is substantially the same as the absorptive capacity of the napkin of Figure 5, the principal difference in struc ture being the arrangement and number of the layers of creped wadding and the fluff batts and the principal reason for the difference in the two napkins is with respect to the flow distributing characteristics.

Figures 6 and'7 illustrate the manner in which the components of Figures 4 and 5, respectively, are assembled so that the napkin has a generally tapered or feathered edge at each end so as to render the napkin less conspicuous when Worn. The components may also be secured together at the end by suitable means such as adhesive or embossments (as illustrated in Figure 11) which not only assist in maintaining the plies in position during assembly and particularly keep the barrier strip 22 from shifting during use and hence fully protect the side ofthe pad not against the body, but also assist in preserving the feathered edge or taper referred to above. Each of the layers of each napkins is, however, shaped to the generally trapezoidal conformation illustrated in Figure 9 so as to provide a thick, but narrow, structure at the central portion and thus afford the highly absorptive and yet form retaining structure which is deemed so desirable. In this way there is a greater amount of absorbent material located where it is most needed while yet providing reduced thickness at the two ends, which contributes to comfort. At the same time, the wider forward end provides more absorptive capacity than the narrow rearward end and this is found to be particularly important in view of the fact that the direction of the menstrual fiow is toward the center and front of the pad due to the forward slant of the channel delivering the menstrual fluid, and thus the pad of the present invention disposes the absorptive material in the most effective position. v

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof, and it is therefore desiredthat the present embodiment be considered in all respects as illustrative and not restrictive, reference being had to the appended claims rather than to the foregoing description to indicate the scope of the invention.

taper, said napkin including a soft, strong, pervious cover and a pad assembly of absorbent material comprising a plurality of layers of fluff and a plurality of layers of creped wadding, said absorbent material being distributed in approximately equal amounts at the opposite faces of an impervious generally central barrier, said barrier having its edges coextensive with the widest and longest components of the pad, whereby the find and the wadding on only one face of said barrier absorb menstrual fluid during use and the fluff and wadding on the opposite face of said barrier remain dry and firm.

2. A relatively thick and narrow double faced sanitary napkin having a confimlration which conforms to the female anatomy by being generally trapezoidal in the direction of its long axis and being thicker at the central portion than at the ends to provide a double longitudinal taper, said napkin including a soft, strong, pervious cover and a pad assembly of absorbent material comprising a plurality of layers of fluff and a plurality of layers of creped wadding, said absorbent material being distributed in approximately equal amounts at the opposite faces of an impervious generally central barrier, said barrier having its edges coextensive with the Widest and longest components of the pad and being secured to the material adjacent the barrier to prevent lateral movement of the barrier within the pad, whereby the fluff and the wadding on only one face of said barrier absorb menstrual fluid during .use and the fluff and wadding on the opposite face of said barrier remain dry and firm.

References Cited in the file of this patent UNITED STATES PATENTS Belgium Apr. 15, 1954

Images