Patent 3710797 - DISPOSABLE DIAPER
|United States Patent||Patent Number 3,710,797|
|Marsan||Issued January 16, 1973|
A disposable diaper is provided with a plurality of scored fold lines arranged in a symmetrical, complex pattern including a central dividing line so that the diaper can be folded on itself prior to use. Four pairs of inwardly directed folds originate from the side edges of the diaper to define two pairs of angular symmetrical areas of essentially triangular configuration having a common base on opposites sides of the central dividing line. The configuration of the scores is such that when the diaper is folded in half, the said angular symmetrical areas form a double gusset fold. This preforms the diaper into a particularly useful form which is easily fitted to an infant so that it snugly conforms to his legs when the diaper is pinned in place.
|Inventors:||Mario S Marsan (Springfield Township Hamilton County OH)|
|Assignee:||The Proctor (Cincinnati, OH)|
|Filed:||February 26, 1971|
|Current U.S. Class:||604/385201 - 604/370 - 604/374|
|Current CPC Class:||A61F 13/49001 (20130101)|
|Current International Class:||A61F013/15 (20060101)|
|Field of Search:||;128/280,284,287|
|3180335||April 1965||Duncan et al.|
CROSS-REFERENCE TO RELATED APPLICATION
This is a continuation-in-part of application Ser. No. 825,094, filed Apr. 15, 1960 and now abandoned which, in turn, is a continuation-in-part of application Ser. No. 803,768, filed Mar. 3, 1969, now abandoned.
What is claimed as new is:
1. A disposable diaper comprising a plurality of superposed layers including a topsheet, a layer of absorbent materials and a bottom sheet, said diaper having a plurality of folds including infolds and outfolds to permit folding over on itself prior to actual usage, said folds including:
a. a central fold separating the diaper into two portions, said central fold including outer infolds, a central infold and an intermediate outfold between said central infold and each of said outer infolds,
b. an inner point at the joinder of each of said intermediate outfolds with the central infold
c. an intermediate point at the joinder of each of said intermediate outfolds with its adjoining outer infold,
d. two outfolds extending inwardly on each said portion from opposite side edges of the diaper, said last mentioned outfolds each extending toward the intermediate point nearest the side edge from which it originates,
e. two infolds extending inwardly on each said portion from opposite side edges of the diaper, said last mentioned infolds each extending toward the inner point nearest the side edge from which it originates, and
f. said central infold having a length of from about 1 inch to about 4 inches to obtain optimum fit of said diaper as measured by its containment characteristics.
2. A disposable diaper as claimed in claim 1 wherein said infolds extending inwardly from the side edges are joined at the inner points by a small radius and said outfolds extending inwardly from the side edges are joined at the intermediate points by a small radius.
3. A disposable diaper as claimed in claim 2 wherein said diaper includes a plastic bottom sheet and said infolds and outfolds extending from the side edges are formed by narrow lines of discontinuity in the absorbent material.
4. A disposable diaper as claimed in claim 3 wherein the absorbent material of the diaper is an airfelt material substantially uniformly distributed between the topsheet and the bottom sheet.
BACKGROUND OF THE INVENTION
In the past decade, the advent of the disposable paper diaper has revolutionized the diapering of infants. Disposable diapers found in the market place today have a variety of fold configurations and are characterized by various combinations of paper and absorbent materials. Most present day diapers have at least one common drawback in that they require the consumer to perform a difficult manipulative process in order to properly conform the diaper to the complex contours of the infant. The location of the functional components of the diaper, i.e. the absorptive materials, frequently hinder and further complicate the folding process. Thus, while most consumers regard this type of product as a great advance in the art, still one of the most frequent complaints is the lack of a more practical folding configuration which would make the placement of the diaper on the infant a bit less tedious.
SUMMARY OF THE INVENTION
The nature and substance of the invention will be more readily appreciated after giving consideration to its principal objectives.
A major object of the invention is the provision of a disposable diaper which is folded in such fashion that it is readily opened and applied to the infant without excessive manipulation by the consumer.
Another object of the invention is the provision of such a diaper in which the components thereof are located so that their function is performed most effectively and with the least interference with the conformability and fit of the diaper on the infant.
A further object of the invention is the provision of a disposable diaper of the above character which is also provided with a pocket of optimum width and minimum depth in order that it will carry out its absorptive functions effectively and efficiently without placing excessive bulk of material in the crotch of the infant.
A still further object of the invention is the provision of a diaper as aforesaid which is folded in compound fashion and yet can be readily folded in half to permit packaging in flat compact form prior to use without affecting the relative ease with which the diaper is converted from its folded form when fitted on an infant.
These and other objects are achieved by the provision of a disposable diaper having a plurality of superposed layers of paper and absorbent materials. The diaper is formed with a plurality of scored folds including infolds and outfolds to permit it to be readily folded in half prior to actual usage. The folds include a central fold which divides the diaper across its central portion. The central fold is alternately divided into infolded and outfolded portions. A plurality of symmetrically placed infolds and outfolds extend from the central fold to the opposite side edges of the diaper to provide two pairs of symmetrical angular areas of essentially triangular configuration above and below the central fold line at each edge. When the diaper is folded on itself, the symmetrical angular areas are formed into a double gusset fold.
BRIEF DESCRIPTION OF THE DRAWING
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter regarded as forming the present invention, it is believed the invention will be better understood from the following description taken in connection with the accompanying drawing in which:
FIG. 1 is a fragmentary perspective view of the diaper of the invention showing the configuration of the several score lines which achieve the preferred folding configuration.
FIG. 2 is a perspective view of the diaper of FIG. 1 after the diaper has been partially folded over on its central fold line.
FIG. 3 is a perspective view illustrating the diaper of the invention after it has been folded nearly in half thereby illustrating its compact and convenient form prior to actual usage.
FIG. 4 is a perspective view of the diaper illustrating its configuration when pinned in place on an infant.
FIG. 5 is a fragmentary elevation illustrating the operative components of a line scoring apparatus that can be employed to emboss the fold lines on the diaper in order to achieve the preferred folding effect.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Referring now to the drawings and particularly to FIG. 1 thereof, a disposable diaper 10 is illustrated. The diaper 10 is fabricated from the usual multiple layers of various materials which may typically include tissue paper, crepe paper, nonwoven fabrics as well as suitable absorptive fillers such as wadding, cellulosic fluff or airfelt materials in suitable combinations as will be appreciated by those familiar with the art.
The preferred construction of the diaper illustrated in FIG. 1 comprises a bottom sheet 11 which is made from a suitable paper or nonwoven fabric material, this being the sheet which is normally furthest removed from the skin of the infant. A crepe layer 12 is superposed over the bottom sheet 11. The layer 12 is in turn covered with a layer of cellulosic fluff or airfelt 13. The three lowermost layers constitute the outer foundation for the entire diaper throughout its area there being one or more narrow layers of absorptive material supported medially thereof as will now be described.
The central portion of the preferred diaper is characterized by a plurality of preformed absorptive strips which are superposed over the airfelt layer 13 in the course of assembly. These central layers are each composites containing opposite outer layers of tissue paper and/or crepe paper there being a layer of airfelt material interposed therebetween.
In the preferred construction, a first narrow layer 14 which is about one-third the overall width of the entire diaper is placed upon the airfelt layer 13 essentially as shown in the drawing. The narrow layer 14 is preferably comprised of a composite sheet of wet strength crepe paper 15, airfelt 16 and wet strength crepe paper 17. The layer 14 is preferably embossed with a typical diamond network pattern to join the materials and to reduce their overall bulk.
In the present construction, a second narrow composite layer 18 is placed upon the layer 14. The layer 18 is also a composite of wet strength crepe paper 19, airfelt 20 and wet strength crepe paper 21. The components in the layer 18 are superposed and cling together without embossing. It should be noted that the second narrow layer 18 is preferably slightly wider than the first layer 14 (about one-fourth inch on each side) so that the side edges of the layers 14 and 18 do not create an exaggerated step in cross section.
Any one or more of the airfelt layers 13, 16 and 20 can be replaced with paper wadding or other bulk materials having the necessary hydrophilic properties to achieve similar results. However, in the present combination, airfelt is preferred for each of these layers by reason of economy, efficiency and ease of assembly.
A full layer of tissue or wet strength crepe paper 22 covers the narrow central layers 14 and 18 and the entire assemblage is covered by a topsheet 23 which is ultimately placed against the skin of the infant when the diaper is in use. The topsheet 23 preferably has hydrophobic characteristics and can be either a saturated paper or nonwoven fabric material.
The several layers of the diaper as heretofore described are placed in the stated superposed relationship as the diaper 10 is passed through an assembly operation. The edges of the bottom sheet 11 and topsheet 23 are joined by suitable adhesives either with or without the lapping of the edges of one over the other. Preferably, however, the edges of the topsheet 23 are lapped over and adhered to complete the assembly and hold the several layers in their desired relationship.
A pattern of embossed fold lines is then impressed into the assembled diaper in order that it readily folds in half essentially as shown in FIG. 3. The fold lines are embossed into the diaper so that each can be characterized as either an "infold" or an "outfold." For purposes of the ensuing description, an "infold" will be understood to mean an embossed line on the diaper which will naturally cause the surface areas of the paper topsheet 23 lying on either side of the "infold" to fold into superposed relation when the end edges 24 and 25 are brought together in the manner illustrated in FIG. 3; similarly, an "outfold" will be understood to mean an embossed line on the diaper which will naturally cause the surface areas of the bottom sheet 11 lying on either side of the "outfold" to fold into superposed relation when the end edges 24 and 25 are brought together.
The completed disposable diaper 10 is provided with a predetermined pattern of infolds and outfolds to achieve the objects of the invention. A composite central fold 26 is provided extending from the end point 27 to the end point 28. The central fold 26 separates the entire diaper 10 into approximately equal portions. The central fold 26 includes a central infold 29 extending between the inner point 30 and the inner point 31. Intermediate outfolds 32 and 33 are provided extending outwardly from the inner points 30 and 31, respectively, to the intermediate points 34 and 35, respectively. The outer infolds 36 and 37 extend to the end points 27 and 28, respectively, from the intermediate points 34 and 35, respectively.
Referring again to FIG. 1, it will be noticed that the reference numerals 18a and 18b designate the side edges of the narrow composite layer 18. The edges 18a and 18b intersect the intermediate outfolds 32 and 33, respectively, in relative close proximity to the inner points 30 and 31, respectively. As a consequence of this construction, the majority of the fold lines (both infolds and outfolds) lie beyond the edges of the central composite layer 18. This results in a superior folding structure as will be hereinafter described.
Outer points 38, 39, 40 and 41 are provided as convergence points for additional infolds and outfolds along the side edges of the diaper preferably so that each outer point is further from the central fold 26 than it is from its nearest end edge 24 or 25. Each of the outer points 38, 39, 40 and 41 preferably lies at about the same distance from the central fold 26. Extending from the outer points are the infolds 42, 43, 44 and 45. The infolds 42 and 43 merge at the inner point 30 and the infolds 44 and 45 merge at the inner point 31. Similarly, outfolds 46 and 47 extend from the outer points 38 and 40, respectively, to the intermediate point 34; and outfolds 48 and 49 extend from the outer points 39 and 41, respectively, to the intermediate point 35.
With the above combination of infolds and outfolds, the diaper 10 is readily folded on itself during which manipulation it passes through the configuration illustrated in FIG. 2. This is accomplished by merely bringing the outer edges 24 and 25 together so that the central infold 29 in effect functions as a hinge point. In the course of the folding sequence, the inner triangular areas 50, 51, 52 and 53 on either side of the intermediate outfolds 32 and 33 fold inwardly (see FIG. 2) against the areas of the topsheet 23 which adjoin the infolds 42, 43, 44 and 45, respectively. Similarly, the outer triangular areas 54, 55, 56 and 57 formed on either side of the outer infolds 36 and 37 fold together in pairs 54-55 and 56-57 as a result of the outfolds 46, 47, 48 and 49. Thus, when the diaper is folded in half as illustrated in FIG. 3, a full double gusset fold is formed at each side by the triangular areas 52-53 and 56-57 on the other side.
While the diaper has been described in its preferred form, it will be apparent that certain modifications can be made without deviating from the basic inventive concept. For example, the infold lines 42-43 and 44-45 can be joined by a small radius where they merge on the composite central fold 26 at the points 30 and 31, respectively. The same can be done to the merger of the outfolds 46-47 and 48-49, i.e. they can be joined by a small radius at the points 34 and 35, respectively. Additionally, the terminus of the infold 43 and outfold 47 at the outer point 40 can be spaced a relatively short distance so that they intercept the side edge of the diaper at relatively closely spaced points. The latter structure can also be carried out with respect to the infold 42 and outfold 46, the infold 44 and outfold 48, and the infold 45 and outfold 49. In the latter arrangement, the triangular areas 50-57, inclusive will take the form of symmetrical angular areas of generally triangular configuration.
The diaper 10 is normally supplied in the folded condition illustrated in FIG. 3. When it is to be used, the edges 24 and 25 are merely separated sufficiently to fit the diaper snugly and comfortably to an infant whereupon the edges 24 and 25 form a continuous waistband when the corners are pinned.
It will be appreciated by an examination of FIG. 4, that the double gusset folded areas tend to readily conform to the thigh portions of the leg of the infant. This allows quick and easy fitting and provides a snug and comfortable diaper fit that will neither bind nor wad on the infant as can occur when the diaper is improperly folded with some presently known constructions.
It will also be apparent that a pocket is formed in the lower portion of the diaper between the inner points 30 and 31. Preferably, therefore, the points 30 and 31 are spaced sufficiently apart so that the resultant pocket is of optimum width and minimum depth. This allows the normal diapering functions to be performed without placing an excessive amount of bulky diaper material in the crotch of the infant. In order to obtain best diaper fit as measured by optimum containment of fluids and waste material, it has been found that the length of the central infold 29 is critical. Best results are obtained with a central infold 29 of from about 1 inch to about 4 inches in length and preferably from about 2 inches to about 3 inches in length. When the length of infold 29 is less than about 1 inch there is a significant reduction in fluid containment because of the proximity of the outer triangular areas 54-57. When greater than 4 inches, there is a significant reduction in the fit at the leg opening which also reduces diaper containment efficiency for fluids and other wastes.
Another of the superior characteristics of the present construction is the provision of four points, viz, the inner points 30 and 31 and the intermediate points 34 and 35, on the central fold 26. The use of four points allows the infolds 42, 43, 44 and 45 to radiate from two spaced inner points 30 and 31; similarly, it allows the outfolds 46, 47, 48 and 49 to radiate from the intermediate points 34 and 35. The provision of these spaced radiation points allows the diaper to be readily transformed from its flat folded configuration (FIG. 3) to a shaped body fitting configuration as in FIG. 4. In other words, it results in a diaper construction which is much more easily conformed to the complex contours of the infant.
In order to maintain the shape and configuration for optimum performance when in use, the placement of glue spots is preferred to hold certain areas of the diaper in place. For example, a glue spot in the area denoted by the distal end of the lead line from the reference numeral 51 will hold the inner triangle 51 in relative superposition against the corresponding area of the topsheet 23. Preferably the glue spot is placed from about one-fifth to about one-half the distance downwardly from the outer point 40 in terms of the height of the triangle 51 as measured between the infold 43 and the outfold 47, and about in the middle one-third measured transversely between the infold 43 and the outfold 47. Similarly placed glue spots can also be applied to the inner triangles 50, 52 and 53. The outer triangles 54-57 can also have a similar glue spot applied thereto on the bottom sheet 11 in a similar location in relation to their respective outer points to hold them in relative superposition with respect to the bottom sheet 11.
It is also worthy of mention that certain functional advantages accrue because of the presence of the intermediate outfolds 32 and 33 which are interposed between the central infold 29 and the outer infolds 36 and 37, respectively. The primary advantage obtained from this central fold configuration is the provision of a diaper that is snugger fitting around the legs and lower body of the infant with a fit that is more comfortable since the folds minimize and distribute excessive bulky diaper material. As a result of the snugger fit obtained because of this fold configuration, the diaper is less likely to leak or, in other words, its containment characteristics are greatly enhanced. There is no need to expound on the desirability and virtues of this attribute.
It was previously indicated that the edges 18a and 18b of the second narrow composite layer 18 intersect the intermediate outfolds 32 and 33, respectively. As a result of this preferred diaper construction, the majority of the length of each of the infolds 42, 43, 44 and 45 and the entire lengths of the outfolds 46, 47, 48 and 49 lie beyond the edges 18a and 18b. In other words, the heavy absorbent central strip comprising the superposed composite central layers 14 and 18 are not encumbered with these fold lines. This results in a fold structure in which the leg folds are less bulky. It also provides one additional reason for which the diaper is snugger fitting and less prone to leakage in addition to the characteristics and structural features previously mentioned.
After pinning the diaper in place, a pair of conventional pants made from plastic or other water impervious material may be worn by the child. In some cases it may be desirable to cover the bottom sheet 11 of the diaper with an integral layer of thin plastic material to eliminate the need for separate plastic pants.
FIG. 5, illustrates the principal portions of an apparatus for making the infolds and outfolds in the diaper in order to obtain the preferred folding effect for each of the fold lines previously described. For purposes of illustration, the manner of forming the outer infold 37 will be described, it being understood that all of the other folds (both infolds and outfolds) can be made in like fashion.
In the area of the infold 37, the diaper is composed of the bottom sheet 11, the crepe paper layer 12, the airfelt layer 13, the tissue or crepe paper layer 22 and the paper topsheet 23. The formation of an infold or a preferential folding effect is obtained by compressing the diaper assembly to emboss a fold that is predisposed to folding inwardly, i.e. so that the surfaces of the topsheet 23 on either side of the fold 37 tend to fold together.
This effect can be accomplished by the use of a suitably shaped steel rib 58 which is preferably about one-eighth inch wide with its leading edge tapering inwardly and terminating in a flat 59 preferably about 3/64 of an inch in width. The flat 59 is pressed into the diaper material which is supported by a resilient rubber backing 60 so that the latter is penetrated about one-eighth of an inch. This requires a pressure which can vary anywhere from 10 pounds per lineal inch of rib to 1000 pounds per lineal inch of rib depending on the diaper materials and the hardness of the rubber coil. The outfolds are similarly formed except that the steel rib is impressed into the assemblage from the side covered by the bottom sheet 11. The entire configuration of infolds and outfolds can be formed in this fashion.
When making diapers on a production basis, the infolds and outfolds can be formed by providing a first roller having suitable steel ribs placed thereon for embossing all of the infolds, and; a second roller having suitable steel ribs placed thereon for embossing all of the outfolds. The diaper is properly embossed for folding after passing beneath each of the rollers which are suitably backed by cooperating rubber rolls. It is also possible to pass the diaper between a single pair of rollers in which the infolds and outfolds will all be embossed into the diaper in one pass. In any case, compression of the airfelt when embossing the fold lines is a key factor in causing a tendency in the diaper to fold on the fold lines in the direction from which it is embossed.
As an alternative, articulated folds can be provided in place of the embossed infolds 42-45 and the embossed outfolds 46-49. These are formed by providing narrow (about one-fourth inch to about three-eighths inch) discontinuities or lines of isolation in the absorbent material and adhering the bottom sheet 11 and topsheet 23 in these areas. Best results are obtained in this type of structure by providing a plastic bottom sheet 11 and adhering it to the topsheet 23 in the narrow areas of the discontinuities which then form articulated infolds 42-45 and articulated outfolds 46-49. An example of a diaper structure of this kind is described in the co-pending application of Mario S. Marsan, Ser. No. 53,762, filed July 10, 1970. titled DISPOSABLE DIAPER WITH IMPROVED CONTAINMENT CHARACTERISTICS which is also assigned to the assignee of the present invention.
While particular embodiments of the invention have been illustrated and described, it will be obvious to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the invention and it is intended that all such changes and modifications are within the scope of this invention.