CA1272851A - Paper diaper - Google Patents
Paper diaperInfo
- Publication number
- CA1272851A CA1272851A CA000515842A CA515842A CA1272851A CA 1272851 A CA1272851 A CA 1272851A CA 000515842 A CA000515842 A CA 000515842A CA 515842 A CA515842 A CA 515842A CA 1272851 A CA1272851 A CA 1272851A
- Authority
- CA
- Canada
- Prior art keywords
- layer
- crust
- fluid
- diaper
- partition
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Absorbent Articles And Supports Therefor (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A paper diaper comprises, from the top downwards, a fluff pulp surface layer or ply, a holed or grooved partition layer, a diffusion crust layer, and a fluff pulp main layer or ply, all wrapped up in a non-woven fabric. When the diaper is worn, fluid discharged is absorbed in a somewhat localized area, passes downwards through this area, and then falls down through the partition layer onto the crust layer which diffuses the fluid throughout substantially the whole area of the diaper and also retains some. Thus, the whole of the diaper is slightly moistened but does not cause any dis-comfort such as a drippingly wet feeling. Flowing back of the fluid from the crust layer to the surface layer is prevented by the partition layer.
A paper diaper comprises, from the top downwards, a fluff pulp surface layer or ply, a holed or grooved partition layer, a diffusion crust layer, and a fluff pulp main layer or ply, all wrapped up in a non-woven fabric. When the diaper is worn, fluid discharged is absorbed in a somewhat localized area, passes downwards through this area, and then falls down through the partition layer onto the crust layer which diffuses the fluid throughout substantially the whole area of the diaper and also retains some. Thus, the whole of the diaper is slightly moistened but does not cause any dis-comfort such as a drippingly wet feeling. Flowing back of the fluid from the crust layer to the surface layer is prevented by the partition layer.
Description
2~
FIELD OF THE INVENTION
This invention relakes to diapers for absorbing and retaining fluid such as urine, and particularly to paper diapers having fluff pulp as a primary element.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a diagrammatic cross-sectional view across the width of a basic embodiment of the paper diapex of the invention, a portion of the width being omi-tted for simplicity;
FIG. 2 is a fragmentary perspective view of a portion of a main part Qf the paper diaper of Fig. l;
FIG.3 is a fragmentary perspective view, similar to Fig. 2, of a second embodiment of the invention having a modified partition layer;
FIG. 4 is a fragmentary perspective view of a third embodiment of the invention having a separately formed partition l~yer;
FIG. 5 is a fragmentary perspective view of a further embodiment of a separately formed partition layer;
FIG. 6 is a fragmentary perspective view of yet a further en~bodiment of a separately formed partition layer; and FIG. 7 is a diagrammatic cross-sectional view across the width of a prior art paper diaper.
BACKGRO~ND OF THE INVENTION
Heretofore, ma~y paper diapers have utilized fluff pulp for absorbing the fluid. Fig. 7 of the accompanying drawings illustrates a typical structure of a paper diaper of the prior art.
, ,: . : . . ' : . . -~L~7~51 In the diaper of Fig. 7, a fluff pulp layer "b" of a certain thickness is disposed on a suitable support paper "a", a vinyl sheet "c" covers underneath the support paper "a", and a non-woven sheet "d" is placed on top of the fluff pulp layer "b". Side edges "e" and "e"' of the diaper are heat sealed, and both ends in the longitudinal direction, that is the direction perpenducular to the sheet of the drawing, are also heat sealed to provide a finished product. As to specific shapes of the product, there are flat ones for the adult, folded ones to fit the groin to be fastened about the waist, or rolled up ones with side edges shrunk for infants.
The fluff pulp which is used as a principal material of such paper diapers is produced relatively at a low cost and is well accepted by the industry. However, it is a mass of short fibers with the fibers being little entwined with each other, so that it is unable to maintain a given shape and collapses easily. Since the fibers are not entwined in the fluff pulp, and there exists substantial gaps or clearance between the fibers, there - la -, _ ` ' ' , ' ', ' " '' '~ "
ls generated no capillary action and the fluid cannot be transferred throughout the mass of fluff pulp. Despite these shortcomings, ~luPf pulp is generally used as the principal element of a liquld or fluid absorbing diaper.
S Applicant has observed closely the conditions of absorb-ing and retaining the excretion, particularly ~luid such as urine, and referred to generally herein as the fluid, and realized there are several problems that must be settled. Tne discharged fluid passes through the ex--~ ternal member, that is the non-woven fabric t'd", which is in direct contact with a human body, to permeate and slnk into the fluff pulp layer "bi', but such permeation and sinking of the fluid is substantially confined or limited to a local area ~ enclosed by dotted lines in Fig. 7. This area R is coextensive with an arez of the diaper where the fluid excreted from the human body makes contact with the diaper. Even if the fluid per-meates and sinks into the thickness of the fluff pulp layer "b", there is no spreading of the fluid in the lateral direction "~' of the diaper. Likewise, there is no spreading of the fluid in the longitudinal direction.
The ~luld merely sinks down in substantially perpendicular direction ~z" causing the fluff pulp to cave-in. When a large ~uantity of fluid is discharged locally, the 2~ area R cannot retain the fluid within itself, and part o~ the fluid penetrates to the Sur~acQ of the vinyl sheet "c" at the bottom and starts flowing out therefrom over the internal sur~ace of the vinyl sheet "c". Some portion of the fluid seeps along the fluff pulp surround-
FIELD OF THE INVENTION
This invention relakes to diapers for absorbing and retaining fluid such as urine, and particularly to paper diapers having fluff pulp as a primary element.
BRIEF DESCRIPTION OF THE DRAWINGS
In the accompanying drawings:
FIG. 1 is a diagrammatic cross-sectional view across the width of a basic embodiment of the paper diapex of the invention, a portion of the width being omi-tted for simplicity;
FIG. 2 is a fragmentary perspective view of a portion of a main part Qf the paper diaper of Fig. l;
FIG.3 is a fragmentary perspective view, similar to Fig. 2, of a second embodiment of the invention having a modified partition layer;
FIG. 4 is a fragmentary perspective view of a third embodiment of the invention having a separately formed partition l~yer;
FIG. 5 is a fragmentary perspective view of a further embodiment of a separately formed partition layer;
FIG. 6 is a fragmentary perspective view of yet a further en~bodiment of a separately formed partition layer; and FIG. 7 is a diagrammatic cross-sectional view across the width of a prior art paper diaper.
BACKGRO~ND OF THE INVENTION
Heretofore, ma~y paper diapers have utilized fluff pulp for absorbing the fluid. Fig. 7 of the accompanying drawings illustrates a typical structure of a paper diaper of the prior art.
, ,: . : . . ' : . . -~L~7~51 In the diaper of Fig. 7, a fluff pulp layer "b" of a certain thickness is disposed on a suitable support paper "a", a vinyl sheet "c" covers underneath the support paper "a", and a non-woven sheet "d" is placed on top of the fluff pulp layer "b". Side edges "e" and "e"' of the diaper are heat sealed, and both ends in the longitudinal direction, that is the direction perpenducular to the sheet of the drawing, are also heat sealed to provide a finished product. As to specific shapes of the product, there are flat ones for the adult, folded ones to fit the groin to be fastened about the waist, or rolled up ones with side edges shrunk for infants.
The fluff pulp which is used as a principal material of such paper diapers is produced relatively at a low cost and is well accepted by the industry. However, it is a mass of short fibers with the fibers being little entwined with each other, so that it is unable to maintain a given shape and collapses easily. Since the fibers are not entwined in the fluff pulp, and there exists substantial gaps or clearance between the fibers, there - la -, _ ` ' ' , ' ', ' " '' '~ "
ls generated no capillary action and the fluid cannot be transferred throughout the mass of fluff pulp. Despite these shortcomings, ~luPf pulp is generally used as the principal element of a liquld or fluid absorbing diaper.
S Applicant has observed closely the conditions of absorb-ing and retaining the excretion, particularly ~luid such as urine, and referred to generally herein as the fluid, and realized there are several problems that must be settled. Tne discharged fluid passes through the ex--~ ternal member, that is the non-woven fabric t'd", which is in direct contact with a human body, to permeate and slnk into the fluff pulp layer "bi', but such permeation and sinking of the fluid is substantially confined or limited to a local area ~ enclosed by dotted lines in Fig. 7. This area R is coextensive with an arez of the diaper where the fluid excreted from the human body makes contact with the diaper. Even if the fluid per-meates and sinks into the thickness of the fluff pulp layer "b", there is no spreading of the fluid in the lateral direction "~' of the diaper. Likewise, there is no spreading of the fluid in the longitudinal direction.
The ~luld merely sinks down in substantially perpendicular direction ~z" causing the fluff pulp to cave-in. When a large ~uantity of fluid is discharged locally, the 2~ area R cannot retain the fluid within itself, and part o~ the fluid penetrates to the Sur~acQ of the vinyl sheet "c" at the bottom and starts flowing out therefrom over the internal sur~ace of the vinyl sheet "c". Some portion of the fluid seeps along the fluff pulp surround-
3~ ing, and in contact with, the vinyl sheet, but sinCQ thefluff puip is unable to absorb the fluid by itself, the amount of the fluid that so seeps is limited; most of this fluid collects on the vinyl sheet surrounding the area R and leaks laterally towards the side edges. In , - . - , . ' .
. - .
5~
order to prevent this lateral leaking, it will become neressary to perform additional steps, for example, to tighten that part o~ the diaper which contacts the groin into a cup-like shape, or to shrink the side edges. Such will merely increa~e the manufncturing cost while serving little purpose of dispersing or diffusing the fluid.
Further, lf the lateral leakage is prevented by means of the additional steps just described, the area R be-comes a gorge of the diaper when worn by a person. The fluid collects in this gorge-like part in quantity and wets the area R drippingly while the fluff pulp outside the area R is not wet at all. This condition is felt by a wearer who feels discomfort in using the diaper. Thus, the flu~f pulp, which has been prepared ~or tha purpose of absorbing and retaining the fluid, ~ctually causes this localized "fluid collection" which brings about a contrary effect of giving the wearer a thoroughly wet feeling. In addition, m~st of the remain-ing fluff pulp does not function to absorb and retain the fluid, which means a gross waste or uneconomical use of a signi~icant amount of the material making up the diaper.
In order to try and improve the poor performance in ab-sorbing and retaining the ~luid when using fluff pulp, it has been proposed to use high polymer absorbing material together therewith. Re~erring to Fig. 7, the high polymer absorbent can be inserted between the support sheet "a" and the ~luf~ pulp layer "b". Pulverized polymer contained in the high polymer absorbent has a high degree ofhydrophilic property and is capable of ab-sorbing an amount of fluid sixty times its own weight, havlng tne characteristics of taking in the fluid while it swells and is gelled. However, since it does not possess the property of dispersing fluid, it cannot trans ~er the fluid laterally to the remaining dry polymer, even when the polymer under the area R is satura-ted with the fluid.
It is not only incapable of solving the problem of local "fluid collection" in the fluff pulp, but also presents another problem of increasing the product cos-t since the high polymer absorbent is expensive.
SV~MARY OF THE INVENTION
This invention is concerned with solving or mitigating tlle problems of discomfort in use resulting from the wet feeling caused by localized flùid collection, waste or uneconomical use of raw material, and increase of manufacturing cos-t.
Accordingly, it is an object of the invention to provide a paper diaper which is pleasant to use yet inexpensive to manufacture, wherein the main element of the diaper is the fluff pulp, and substantially the whole of which is effectively utilized to maximize absorption and retention of the fluid.
Another object of the invention is to minimize the overall si~e of the diaper while obtaining effective fluid absorption and retention.
According to the present invention there is provided apaper diaper comprising: a surface layer of fluff pulp in which fibers thereof are not entwined but are aggregated together; a partition layer having spaced-apart openings therein and being located under the surface, the partition layer being non-absorbent but the openings allowing fluid to fall down therethrough; a crust layer comprising fluff pulp fibers which are oriented in a longitudinal direction of the paper diaper and are bonded to each other, the crust layer being disposed under the partition layer ,, , . , : , .. .
, :
.
, .
~.~7~5~L
to receive and diffuse in an oriented manner the fluid falling down through the openings in the partitlon layer and to retain at least some of the fluid; a fluff pulp main layer disposed under the crust layer and comprising Eluff pulp fibers which are not essentially entwined and bonded to each other; the main layer having upstanding peripheral edge portions between which the crust layer is disposed; the main layer being integrally continu-ous with a lower part of the crust layer and the upstanding peripheral edge portions being integrally continuous with edge portions of the crust layer; the crust layer being enclosed by the partition layer, the upstanding peripheral edge portions and the main layer, and an outer covering enclosing the layers.
The fluff pulp of the surface layer or ply allows the 1uid to permeate therethrough within a localized area, the crust layer under the partition layer diffuses and retains the fluid over a wide area, so that the diaper of the invention conveys to the user a soft touch without giving a wet feeling, and offers a pleasant feeling in use. The fluid/ after passing through the fluf pulp of the surface layer or ply over a narrow area ~lightly wider than the local area where the fluid is discharged, passes through the holes or o-ther openings in the partition layer to the crust layer. The crust layer exerts, by means of capillary action, its inherent diffusion and retaining properties over a much wider area to distribute and permeate the fluid in a small quantity per unit area to the main ].ayer or ply of fluff pulp at both the forward and rear ends of the diaper. Thus, the fluid is caused to be dispersed and retained inside substantially the whole area of the diaper, allowing the diaper to be only slightly moistened throughout. There is no locali~ed : . . . .
~L~7X~5~
or concentrated collection of fluid at or in any of the partltion layer, diffusion crust layer, or the lower main layer or ply of fluff pulp. The interior of the whole of the diaper may give the user n moist~ned feel~ng, however, the diaper does not convey any unpleasant drip-pingly wet feeling, and the edges or ears of the main layer or ply of fluf~ pulp remaining at both sides of the crust layer effectively prevent lateral leaking of the fluid Other objects, features and advantages of the present invention will become more fully apparent from the follow-ing detailed description of the preferred embodiment, the appended claims and the accompanying drawings.
. --. - . - . ., . ~ . : .
~l~'7 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figs. 1 and 2 ~how a basic embodiment o~ the invention, Fig. i sho~ing schematically a partial cross-section of the paper diaper of the invention, and Fig. 2 is a partial enlarged per~pective view of the principal part o~ the paper diaper of Fig. 1.
The paper diaper o~ the invention comprises malnly a fluff pulp surface layer or ply 1 at the top; a partltion layer 3, with openings, holes or the llke therethrough, which is located under the sur~ace layer and allows the fluid falling down from above to fall down to a lower layer without essentially absorbing the fluid; a crust layer 5 under the partition layer 3 which absorbs the fluid that falls down and disperses such fluid in an orientatèd manner, namely in lateral direction x but pre-dominantly in longitudinal direction y (see Fig. 2); and a ~luf~ pulp main layer or ply 7 inherently and integral-ly continuous to the crust layer 5, with the ~lu~ pulpmain layer 7 and the crust layer 5 being continuous at the lower face 6 of the crust layer as well as at both sides. Slde edges of the fluff pulp main layer 7 form ears 8. Under the fluff pulp main layer 7, there ls placed water resistant paper 9. The whole of the above components are wrapped in a non-woven fabric. Xn Fig. 1, upper and lower non-woven fabrics 10 and 10' are set to gether a.t side edges of the diaper, as shown at 10e, and heat sealed. Instead, it may be so arranged that one continuous sheet of non-woven fabric encloses the whole diaper with the edges heat sealed at one side edge or at the center C of the underside. Although not shown in the drawing, bvth ends in the longitudinal direction are ~imilarly heat sealed to present a completed~paper diaper.
. ~ .
- -'' : ' .' ' ', . : ,:
.
~ 7~
Flu~f pulp comprises a mass of short ~ibers 7 and since short fibers are not essentially entwlned wlth each other, it i8 a mas~ that is ~ragile and collapsible. Such un-twined ~luff pulp flbers are plled together and compressed or the like to form a surface layer or ply 1 of suitable thickness in which short fibers are arranged tightly. It i9 preferable to place suitable deodorant or aromatic under.the surface lay~r 1, or to mix the same in the lower portion thereof. The deodorant or aromatic may be, according to the invention, mixed into fluff pulp in pulverized form or by spraying or the like when the ~lu~f pulp for the surfaoe layer is caused to fall down from a loader to be piled. Any suitable odor improving agent may be used.
In making the crust layer 5, a belt-like body of fluf~
pulp of suitable thickness is placed on a belt, pre-ferably air permeable belt, air is sucked from below the belt to draw the piled fluff pulp down against the belt.
Water in m~nute particles is applied to the upper surface of the belt-like body of fluff pulp by spraying or splashingl so that pulp fibers down to a certain thickness ~rom the surface absorb water. This applying of water should be care~ully executed to avoid cave-in of the fluf~
pulp, or penetration through the whole thickness of the piled pulp sheet due to wetting of a localized area. The thickness of piled pulp sheet that does not absorb water makes the ~luff pulp main layer 7.
Next, preRsure is applied to the upper surface of the ~iber layer along substantially the longitudinal direotion of the belt-like body of the fluff pulp ln a longitudinal tangential direction to orient or align the fibers that absorbed water as much and predominantly as possible in the longitudinal direction. At the same time, this , .' :.. ' ' ' . '- - " ' ' . - , -:
, ~
action causes the oriented fibers to bond tightly to-gether leaving little gap or clearance between them.
Then, by heat drying the fiber layer that absorbed water, the crust layer 5 is formed in which the fibers nearer to the surface are more closely bonded while maintaining their longitudinal orientation.
In the crust layer 5, the fibers, schematically shown in Fiæ. 2 as aligned fibers 5f, are caused to extend pre-dom~nantly and substantially in the same direction, these ~ibers having minute gaps between each other. Thus the bonded aligned fibers will exhibit oaplllary action in the lengthwise direction y, and these flbers form an aggre~ated layer with sufficient strength, due to the bonding o~ the fibers, so that when fluid seeps in there will be no collapsing of the part that absorbs the fluid;
such collapsing would occur if the flu~f pulp ~ibers were simply unorientated and unentwined as in the prior art.
By ad~usting the extent o~ applicatlon of the minute water particles to the surface of fluff pulp, as well as the degree o~ pressure applied, the thickness of the above crust layer and the degree of bonding and the orientation of ~ibers therein may be modified.
Tha lower part 6 of the crust layer 5, wherein the orien-tation and the degree of bonding are weak, is inherently 25 continuous with the fluf~ pulp main layer 7. In the main layer 7, fibers are not entwined nor oriented. In Figs.
1 and 2, the lower part 6 of the crust layer is shown by a dotted llne for the sake o~ convenience, but in reality there is not any clear and definite demarcation between 30 the lower part 6 of the crust layer and the main layer 70 The crust layer 5 is also integrally continuous, at both of its sldes, to both side edges or ears 8 of the fluff pulp main layer 7.
- : .
: ' ~'7~
In order to form the partition layer 3, openings or gaps are ~ormed in the sur~ace of ~he crust layer 5. These openings are created by ~orming, in the crust layer 5, a plurality o~ grooves 2 extending in the longitudinal direction. Grooves 2 may be ~ormed by causing a roller having a plurality o~ annular rib-like protrusions to make contact with the surface o~ the crust layer to make parts o~ the surface corresponding to said protrusions cave in.
Therea~ter, a pharmaceutical, such as a water resistant agent or a water repellent agen*, is applied in suitable manner to the remalning top protruding surface o~ the crust layer to provide a skin or ~ilm 4 which does not absorb water. The sur~ace skin 4 extends between ad-jacent grooves 2. In ~ig. 2 the ~ilm 4 is shown as some-thing that is not transparent, but, in reality, it maybe made transparent so that fibers arranged in the crust layer 5 may be seen therethrough. The grooves 2 are illustrated as being like square waves with sharp edges, but it will be understood that where grooves are made by 2Q pressing with a roller having rib-like protrusions, the edges and bottom o~ the respective grooves take on shapes that do not have sharply de~ined edges. Thus, the parti-tion layer 3 is formed with a number o~ parallel grooves 2 extending in the longitudinal direction with film 4 ~5 located between the tops o~ the grooves. The ~ilm 4,which does not absorb water, is integral with the protruding upper surface o~ the crust layer 5, and repels the ~luid falling down thereon so causing the fluid to ~all down ~urther into the grooves 2; this ~luid then seeps into the absorbent crust layer 5. The ~ilm 4 also ~unction~ to preYent the ~luid which has seeped into the crust layér 5 and, subsequently~ into the fluf~ pulp main layer 7 ~rom flowing back upwardly to the surface layer 1, even when some pressure is applied thsreto.
, . . . .
.
- . .
': .~ '' , ~. - - , ''' : ' ' ':
Flg. 3 is a partial perspective ~iew o~ ano~her embodiment showing another example o~ the partition layer in which a ~ilm 4, that does not absorb water, is attached integral-ly with the crust layer 5' in which many dimples 2' have 5 .been formed. The ~ilm 4' doe~ not cover the concave sur~aces of the dimples 2'. The ~ilm 4' is sh~wn as a transparent element which allows the fibers o~ the crust layer to be seen therethrough.
Unlike the partition layers 3 and 3' integrally ~ormed with the crust layer as explained above, it is pos~ible to provide a partltion layer separate ~rom the crust layer. Fig. 4 shows such an example in a partial per-spective view wherein the partition layer 3" comprise~ a water resistant sheet 13 made o~ paper, non-woven fabric, or the like to which a water resistant or water repellent process has been carried out. Openings 12 are formed through the sheet 13 by making longitudinal slots there-alon~, the slots being closed at each end. Water resist-ant sheet 13 is placed on the sur~ace o~ crust layer 5".
As shown ln Fig. 5, instead o~ slots, a water resls$ant sheet 13' having a number o~ windows 12' punched through it may replace partition layer 3" to be placed on the surface o~ crust layer 5". Each window 12' may be a circular, oval, or other shaped hole.
As a separate partition layer, an open woven fabric 23, like a net, as shown in Fig. 6, on which a water resistant or water repellent process has been carried out, may be employed. Th~ fluid passeS through interstices 22 of the net, is dlspersed thereby and ~alls down onto the crust layer 5, 5'` or 5" upon which the net is supported.
.
, - .
` ~ ' . .
- . - ~ :: . .
,, In the above embodiments, crust layers 5' and 5" are manu~actured similarly to erust layer 5, and similarly integrally merge into the main fluff pulp layer 7~
Now, fluid absorbing and retaining action o~ the paper diaper of the invention will be explained. Referring to Figs. 1 and 2, discharged ~luid passes through non-woven ~abric 10 and ~luff pulp sur~ace layer 1 withing the area R and reaches the partitlon layer 3. Since ~luff pulp sur~ace layer 1 is a mass o~ short fibers not en-twined, the fluid does not stop in the sur~ace layer 1,but soon reaches the apertured partition layer 3 and f~lls into holes, gaps or grooves therebelow. Thus, fluff pulp surface layer 1 in contact with human body does not convey a wet feeling, namely does not give an un-pl~asant ~eeling. Further, the surface layer 1 serves asa buffer means to convey to the skin a feeling of soft touch.
The fluid that reaches onto the impervious film 4 o~ the partition layer 3 cannot be absorbed and spreads in the longitudinal direction, sh~wn by the arrows y in Fig. 2, on top of the ~ilm 4; while some o~ the fluid spreads in the lateral direction shown by the arrows x and drains or falls through the apertures of the film 4 into the grooves 2 below, and then seeps into the crust layer 5 through the locations or areas between the sides of the grooves. Once the ~luid seeps into the crust layer 5, the ~lu~d is prevented from flowing backward (i.e. up-wards) by the partition layer 3. The crust layer 5, which exhibits capillary action predominantly in the longitudinal direction y, draws the ~luid mainly in the longitudlnal direction while drawing some portion in the lateral direction x, thus causing the ~luid to be dis-persed in both longitudinal and lateral directions, - . ' ' , - : . . . :
: .
~' - : ~ . . , ' ' ' ,. '.
:~7~
~ 13 -namely throughout the en-tire area of the paper diaper.
The crust layer 5 does not only diffuse the fluid, but also is capable of retaining a substantial amount o~
fluid in itsel~.
When the ~luid, which has been di~fused and retained over a wlde area of the crust layer in the manner described above9 can no more be retained in the crust layer, the ~luid seeps into the fluf~ pulp main layer 7 as indicated by the arrows z in Fig. 2. Penetratlon of the fluid in ~he z direc~c~on does not take place jus~ w~thin locallzsd area R as explained in connection with the known article shown in Fig. 7, but instead takes place at many places over the wide area of the entire diaper. Consequently, the amount of fluid that seeps into the main layer 7 in this way i8 small per unit areaO Because o~ this, the fluid is prevented from penetrating only a certain local area of the ~luff pulp layer 7 to collect at the bottom thereof, and the entire thickness of the fluff pulp main layer 7 both in longitudinal and lateral directions is evenly moistened by a small amount of the fluid. Thus, the uneconomical de~ect of known diapers in which most o~ the main layer in the longitudinal direction, except for the locali~ed area R, remains dry without absorbing the fluid is avoided, and the fluff pulp main layer 7 is effectively utilized by the present invention. Water repellent paper 9 performs the primary function of supporting the main layer 7, which is slightly and evenly moistened all over as described above, and does not work like a saucer to collect the ~luid penetrating through, and falling down from, the main layer 7. Therefore, that which supports the bottom o~ the water repellent paper 9 need not be a vinyl sheet as in the prior art, but direct wrapping with a non-woven fabric 10', which is advantage-ously gentle to the skin, can be effectively employed.
.
, - , . ~ ' - ' ' . : , ' .
.
However, for the sake of safety, a vlnyl sheet may be employed if desired.
The ears 8, at both side edges of the fluff pulp main layer 7, stop spreadi~gout of the fluid in the lateral direction x beyond the edges of ~he partition layer 3 and diffus1on crust lay~r 5. Since the ears ~ contain a mass of ~ibers not entwined, there is no diffusion and transfer of the fluid, so that the fluid does not seep or leak out laterally. Ears 8 also serve as a buffer when the diaper is applied to a person's body, making the diaper more comfortable to wear.
As will ba realized, the invention has the e~ect as follows: the discharge is widely diffused and distributed over the entire area of the diaper, so that maximum over-lS all effective utilization of the main absorbent materialis reali~ed/ without giving a dripplingly wet feeling to a user even when more fluid than previously possible is absorbed; and if the diaper is to be changed when the same volume o~ discharge fluid as before (i.e. with known diapers) is excreted, the size of the diaper may be made smaller so improving the feeling when the diaper is strapped on the user. Since edges of the fluff pulp of the primary element of the diaper can completely prevent lateral spread and leakage of the fluid, complex addi-tional manufacturing processing, such as shrinking orrolling of the part of the diaper in contact with the groin, may be omitted, and the use of expensive material such as high polymer absorbent is not necessary 80 that the manufacturing costs can be reduced.
In summary, the paper diaper of the invention does not bring about a concentration of fluid collection, and the flu~f pulp main laysr adJacent to the skin is not , - ~
.
- --: :.--' - ; ' :
~ :' . . ,: .. .
~72~
noticeably wetted, and gives a dry and soft feeling to the user which is effective in giving a pleasant feeling in use.
The above described embodiments, of course, are not to be construed as limiting the breadth of the present invention. Modlfications, and other alternative con-structions, will be apparent which are within the spirit and scope of the invention as defined in the appended claims.
.
:
:
:
:
:
. .. . :: .
`~ - : '.. , , .: . .
:
.
:: ` ` ` .: ` :
-. : :~ ~ : . .
. - .
5~
order to prevent this lateral leaking, it will become neressary to perform additional steps, for example, to tighten that part o~ the diaper which contacts the groin into a cup-like shape, or to shrink the side edges. Such will merely increa~e the manufncturing cost while serving little purpose of dispersing or diffusing the fluid.
Further, lf the lateral leakage is prevented by means of the additional steps just described, the area R be-comes a gorge of the diaper when worn by a person. The fluid collects in this gorge-like part in quantity and wets the area R drippingly while the fluff pulp outside the area R is not wet at all. This condition is felt by a wearer who feels discomfort in using the diaper. Thus, the flu~f pulp, which has been prepared ~or tha purpose of absorbing and retaining the fluid, ~ctually causes this localized "fluid collection" which brings about a contrary effect of giving the wearer a thoroughly wet feeling. In addition, m~st of the remain-ing fluff pulp does not function to absorb and retain the fluid, which means a gross waste or uneconomical use of a signi~icant amount of the material making up the diaper.
In order to try and improve the poor performance in ab-sorbing and retaining the ~luid when using fluff pulp, it has been proposed to use high polymer absorbing material together therewith. Re~erring to Fig. 7, the high polymer absorbent can be inserted between the support sheet "a" and the ~luf~ pulp layer "b". Pulverized polymer contained in the high polymer absorbent has a high degree ofhydrophilic property and is capable of ab-sorbing an amount of fluid sixty times its own weight, havlng tne characteristics of taking in the fluid while it swells and is gelled. However, since it does not possess the property of dispersing fluid, it cannot trans ~er the fluid laterally to the remaining dry polymer, even when the polymer under the area R is satura-ted with the fluid.
It is not only incapable of solving the problem of local "fluid collection" in the fluff pulp, but also presents another problem of increasing the product cos-t since the high polymer absorbent is expensive.
SV~MARY OF THE INVENTION
This invention is concerned with solving or mitigating tlle problems of discomfort in use resulting from the wet feeling caused by localized flùid collection, waste or uneconomical use of raw material, and increase of manufacturing cos-t.
Accordingly, it is an object of the invention to provide a paper diaper which is pleasant to use yet inexpensive to manufacture, wherein the main element of the diaper is the fluff pulp, and substantially the whole of which is effectively utilized to maximize absorption and retention of the fluid.
Another object of the invention is to minimize the overall si~e of the diaper while obtaining effective fluid absorption and retention.
According to the present invention there is provided apaper diaper comprising: a surface layer of fluff pulp in which fibers thereof are not entwined but are aggregated together; a partition layer having spaced-apart openings therein and being located under the surface, the partition layer being non-absorbent but the openings allowing fluid to fall down therethrough; a crust layer comprising fluff pulp fibers which are oriented in a longitudinal direction of the paper diaper and are bonded to each other, the crust layer being disposed under the partition layer ,, , . , : , .. .
, :
.
, .
~.~7~5~L
to receive and diffuse in an oriented manner the fluid falling down through the openings in the partitlon layer and to retain at least some of the fluid; a fluff pulp main layer disposed under the crust layer and comprising Eluff pulp fibers which are not essentially entwined and bonded to each other; the main layer having upstanding peripheral edge portions between which the crust layer is disposed; the main layer being integrally continu-ous with a lower part of the crust layer and the upstanding peripheral edge portions being integrally continuous with edge portions of the crust layer; the crust layer being enclosed by the partition layer, the upstanding peripheral edge portions and the main layer, and an outer covering enclosing the layers.
The fluff pulp of the surface layer or ply allows the 1uid to permeate therethrough within a localized area, the crust layer under the partition layer diffuses and retains the fluid over a wide area, so that the diaper of the invention conveys to the user a soft touch without giving a wet feeling, and offers a pleasant feeling in use. The fluid/ after passing through the fluf pulp of the surface layer or ply over a narrow area ~lightly wider than the local area where the fluid is discharged, passes through the holes or o-ther openings in the partition layer to the crust layer. The crust layer exerts, by means of capillary action, its inherent diffusion and retaining properties over a much wider area to distribute and permeate the fluid in a small quantity per unit area to the main ].ayer or ply of fluff pulp at both the forward and rear ends of the diaper. Thus, the fluid is caused to be dispersed and retained inside substantially the whole area of the diaper, allowing the diaper to be only slightly moistened throughout. There is no locali~ed : . . . .
~L~7X~5~
or concentrated collection of fluid at or in any of the partltion layer, diffusion crust layer, or the lower main layer or ply of fluff pulp. The interior of the whole of the diaper may give the user n moist~ned feel~ng, however, the diaper does not convey any unpleasant drip-pingly wet feeling, and the edges or ears of the main layer or ply of fluf~ pulp remaining at both sides of the crust layer effectively prevent lateral leaking of the fluid Other objects, features and advantages of the present invention will become more fully apparent from the follow-ing detailed description of the preferred embodiment, the appended claims and the accompanying drawings.
. --. - . - . ., . ~ . : .
~l~'7 .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figs. 1 and 2 ~how a basic embodiment o~ the invention, Fig. i sho~ing schematically a partial cross-section of the paper diaper of the invention, and Fig. 2 is a partial enlarged per~pective view of the principal part o~ the paper diaper of Fig. 1.
The paper diaper o~ the invention comprises malnly a fluff pulp surface layer or ply 1 at the top; a partltion layer 3, with openings, holes or the llke therethrough, which is located under the sur~ace layer and allows the fluid falling down from above to fall down to a lower layer without essentially absorbing the fluid; a crust layer 5 under the partition layer 3 which absorbs the fluid that falls down and disperses such fluid in an orientatèd manner, namely in lateral direction x but pre-dominantly in longitudinal direction y (see Fig. 2); and a ~luf~ pulp main layer or ply 7 inherently and integral-ly continuous to the crust layer 5, with the ~lu~ pulpmain layer 7 and the crust layer 5 being continuous at the lower face 6 of the crust layer as well as at both sides. Slde edges of the fluff pulp main layer 7 form ears 8. Under the fluff pulp main layer 7, there ls placed water resistant paper 9. The whole of the above components are wrapped in a non-woven fabric. Xn Fig. 1, upper and lower non-woven fabrics 10 and 10' are set to gether a.t side edges of the diaper, as shown at 10e, and heat sealed. Instead, it may be so arranged that one continuous sheet of non-woven fabric encloses the whole diaper with the edges heat sealed at one side edge or at the center C of the underside. Although not shown in the drawing, bvth ends in the longitudinal direction are ~imilarly heat sealed to present a completed~paper diaper.
. ~ .
- -'' : ' .' ' ', . : ,:
.
~ 7~
Flu~f pulp comprises a mass of short ~ibers 7 and since short fibers are not essentially entwlned wlth each other, it i8 a mas~ that is ~ragile and collapsible. Such un-twined ~luff pulp flbers are plled together and compressed or the like to form a surface layer or ply 1 of suitable thickness in which short fibers are arranged tightly. It i9 preferable to place suitable deodorant or aromatic under.the surface lay~r 1, or to mix the same in the lower portion thereof. The deodorant or aromatic may be, according to the invention, mixed into fluff pulp in pulverized form or by spraying or the like when the ~lu~f pulp for the surfaoe layer is caused to fall down from a loader to be piled. Any suitable odor improving agent may be used.
In making the crust layer 5, a belt-like body of fluf~
pulp of suitable thickness is placed on a belt, pre-ferably air permeable belt, air is sucked from below the belt to draw the piled fluff pulp down against the belt.
Water in m~nute particles is applied to the upper surface of the belt-like body of fluff pulp by spraying or splashingl so that pulp fibers down to a certain thickness ~rom the surface absorb water. This applying of water should be care~ully executed to avoid cave-in of the fluf~
pulp, or penetration through the whole thickness of the piled pulp sheet due to wetting of a localized area. The thickness of piled pulp sheet that does not absorb water makes the ~luff pulp main layer 7.
Next, preRsure is applied to the upper surface of the ~iber layer along substantially the longitudinal direotion of the belt-like body of the fluff pulp ln a longitudinal tangential direction to orient or align the fibers that absorbed water as much and predominantly as possible in the longitudinal direction. At the same time, this , .' :.. ' ' ' . '- - " ' ' . - , -:
, ~
action causes the oriented fibers to bond tightly to-gether leaving little gap or clearance between them.
Then, by heat drying the fiber layer that absorbed water, the crust layer 5 is formed in which the fibers nearer to the surface are more closely bonded while maintaining their longitudinal orientation.
In the crust layer 5, the fibers, schematically shown in Fiæ. 2 as aligned fibers 5f, are caused to extend pre-dom~nantly and substantially in the same direction, these ~ibers having minute gaps between each other. Thus the bonded aligned fibers will exhibit oaplllary action in the lengthwise direction y, and these flbers form an aggre~ated layer with sufficient strength, due to the bonding o~ the fibers, so that when fluid seeps in there will be no collapsing of the part that absorbs the fluid;
such collapsing would occur if the flu~f pulp ~ibers were simply unorientated and unentwined as in the prior art.
By ad~usting the extent o~ applicatlon of the minute water particles to the surface of fluff pulp, as well as the degree o~ pressure applied, the thickness of the above crust layer and the degree of bonding and the orientation of ~ibers therein may be modified.
Tha lower part 6 of the crust layer 5, wherein the orien-tation and the degree of bonding are weak, is inherently 25 continuous with the fluf~ pulp main layer 7. In the main layer 7, fibers are not entwined nor oriented. In Figs.
1 and 2, the lower part 6 of the crust layer is shown by a dotted llne for the sake o~ convenience, but in reality there is not any clear and definite demarcation between 30 the lower part 6 of the crust layer and the main layer 70 The crust layer 5 is also integrally continuous, at both of its sldes, to both side edges or ears 8 of the fluff pulp main layer 7.
- : .
: ' ~'7~
In order to form the partition layer 3, openings or gaps are ~ormed in the sur~ace of ~he crust layer 5. These openings are created by ~orming, in the crust layer 5, a plurality o~ grooves 2 extending in the longitudinal direction. Grooves 2 may be ~ormed by causing a roller having a plurality o~ annular rib-like protrusions to make contact with the surface o~ the crust layer to make parts o~ the surface corresponding to said protrusions cave in.
Therea~ter, a pharmaceutical, such as a water resistant agent or a water repellent agen*, is applied in suitable manner to the remalning top protruding surface o~ the crust layer to provide a skin or ~ilm 4 which does not absorb water. The sur~ace skin 4 extends between ad-jacent grooves 2. In ~ig. 2 the ~ilm 4 is shown as some-thing that is not transparent, but, in reality, it maybe made transparent so that fibers arranged in the crust layer 5 may be seen therethrough. The grooves 2 are illustrated as being like square waves with sharp edges, but it will be understood that where grooves are made by 2Q pressing with a roller having rib-like protrusions, the edges and bottom o~ the respective grooves take on shapes that do not have sharply de~ined edges. Thus, the parti-tion layer 3 is formed with a number o~ parallel grooves 2 extending in the longitudinal direction with film 4 ~5 located between the tops o~ the grooves. The ~ilm 4,which does not absorb water, is integral with the protruding upper surface o~ the crust layer 5, and repels the ~luid falling down thereon so causing the fluid to ~all down ~urther into the grooves 2; this ~luid then seeps into the absorbent crust layer 5. The ~ilm 4 also ~unction~ to preYent the ~luid which has seeped into the crust layér 5 and, subsequently~ into the fluf~ pulp main layer 7 ~rom flowing back upwardly to the surface layer 1, even when some pressure is applied thsreto.
, . . . .
.
- . .
': .~ '' , ~. - - , ''' : ' ' ':
Flg. 3 is a partial perspective ~iew o~ ano~her embodiment showing another example o~ the partition layer in which a ~ilm 4, that does not absorb water, is attached integral-ly with the crust layer 5' in which many dimples 2' have 5 .been formed. The ~ilm 4' doe~ not cover the concave sur~aces of the dimples 2'. The ~ilm 4' is sh~wn as a transparent element which allows the fibers o~ the crust layer to be seen therethrough.
Unlike the partition layers 3 and 3' integrally ~ormed with the crust layer as explained above, it is pos~ible to provide a partltion layer separate ~rom the crust layer. Fig. 4 shows such an example in a partial per-spective view wherein the partition layer 3" comprise~ a water resistant sheet 13 made o~ paper, non-woven fabric, or the like to which a water resistant or water repellent process has been carried out. Openings 12 are formed through the sheet 13 by making longitudinal slots there-alon~, the slots being closed at each end. Water resist-ant sheet 13 is placed on the sur~ace o~ crust layer 5".
As shown ln Fig. 5, instead o~ slots, a water resls$ant sheet 13' having a number o~ windows 12' punched through it may replace partition layer 3" to be placed on the surface o~ crust layer 5". Each window 12' may be a circular, oval, or other shaped hole.
As a separate partition layer, an open woven fabric 23, like a net, as shown in Fig. 6, on which a water resistant or water repellent process has been carried out, may be employed. Th~ fluid passeS through interstices 22 of the net, is dlspersed thereby and ~alls down onto the crust layer 5, 5'` or 5" upon which the net is supported.
.
, - .
` ~ ' . .
- . - ~ :: . .
,, In the above embodiments, crust layers 5' and 5" are manu~actured similarly to erust layer 5, and similarly integrally merge into the main fluff pulp layer 7~
Now, fluid absorbing and retaining action o~ the paper diaper of the invention will be explained. Referring to Figs. 1 and 2, discharged ~luid passes through non-woven ~abric 10 and ~luff pulp sur~ace layer 1 withing the area R and reaches the partitlon layer 3. Since ~luff pulp sur~ace layer 1 is a mass o~ short fibers not en-twined, the fluid does not stop in the sur~ace layer 1,but soon reaches the apertured partition layer 3 and f~lls into holes, gaps or grooves therebelow. Thus, fluff pulp surface layer 1 in contact with human body does not convey a wet feeling, namely does not give an un-pl~asant ~eeling. Further, the surface layer 1 serves asa buffer means to convey to the skin a feeling of soft touch.
The fluid that reaches onto the impervious film 4 o~ the partition layer 3 cannot be absorbed and spreads in the longitudinal direction, sh~wn by the arrows y in Fig. 2, on top of the ~ilm 4; while some o~ the fluid spreads in the lateral direction shown by the arrows x and drains or falls through the apertures of the film 4 into the grooves 2 below, and then seeps into the crust layer 5 through the locations or areas between the sides of the grooves. Once the ~luid seeps into the crust layer 5, the ~lu~d is prevented from flowing backward (i.e. up-wards) by the partition layer 3. The crust layer 5, which exhibits capillary action predominantly in the longitudinal direction y, draws the ~luid mainly in the longitudlnal direction while drawing some portion in the lateral direction x, thus causing the ~luid to be dis-persed in both longitudinal and lateral directions, - . ' ' , - : . . . :
: .
~' - : ~ . . , ' ' ' ,. '.
:~7~
~ 13 -namely throughout the en-tire area of the paper diaper.
The crust layer 5 does not only diffuse the fluid, but also is capable of retaining a substantial amount o~
fluid in itsel~.
When the ~luid, which has been di~fused and retained over a wlde area of the crust layer in the manner described above9 can no more be retained in the crust layer, the ~luid seeps into the fluf~ pulp main layer 7 as indicated by the arrows z in Fig. 2. Penetratlon of the fluid in ~he z direc~c~on does not take place jus~ w~thin locallzsd area R as explained in connection with the known article shown in Fig. 7, but instead takes place at many places over the wide area of the entire diaper. Consequently, the amount of fluid that seeps into the main layer 7 in this way i8 small per unit areaO Because o~ this, the fluid is prevented from penetrating only a certain local area of the ~luff pulp layer 7 to collect at the bottom thereof, and the entire thickness of the fluff pulp main layer 7 both in longitudinal and lateral directions is evenly moistened by a small amount of the fluid. Thus, the uneconomical de~ect of known diapers in which most o~ the main layer in the longitudinal direction, except for the locali~ed area R, remains dry without absorbing the fluid is avoided, and the fluff pulp main layer 7 is effectively utilized by the present invention. Water repellent paper 9 performs the primary function of supporting the main layer 7, which is slightly and evenly moistened all over as described above, and does not work like a saucer to collect the ~luid penetrating through, and falling down from, the main layer 7. Therefore, that which supports the bottom o~ the water repellent paper 9 need not be a vinyl sheet as in the prior art, but direct wrapping with a non-woven fabric 10', which is advantage-ously gentle to the skin, can be effectively employed.
.
, - , . ~ ' - ' ' . : , ' .
.
However, for the sake of safety, a vlnyl sheet may be employed if desired.
The ears 8, at both side edges of the fluff pulp main layer 7, stop spreadi~gout of the fluid in the lateral direction x beyond the edges of ~he partition layer 3 and diffus1on crust lay~r 5. Since the ears ~ contain a mass of ~ibers not entwined, there is no diffusion and transfer of the fluid, so that the fluid does not seep or leak out laterally. Ears 8 also serve as a buffer when the diaper is applied to a person's body, making the diaper more comfortable to wear.
As will ba realized, the invention has the e~ect as follows: the discharge is widely diffused and distributed over the entire area of the diaper, so that maximum over-lS all effective utilization of the main absorbent materialis reali~ed/ without giving a dripplingly wet feeling to a user even when more fluid than previously possible is absorbed; and if the diaper is to be changed when the same volume o~ discharge fluid as before (i.e. with known diapers) is excreted, the size of the diaper may be made smaller so improving the feeling when the diaper is strapped on the user. Since edges of the fluff pulp of the primary element of the diaper can completely prevent lateral spread and leakage of the fluid, complex addi-tional manufacturing processing, such as shrinking orrolling of the part of the diaper in contact with the groin, may be omitted, and the use of expensive material such as high polymer absorbent is not necessary 80 that the manufacturing costs can be reduced.
In summary, the paper diaper of the invention does not bring about a concentration of fluid collection, and the flu~f pulp main laysr adJacent to the skin is not , - ~
.
- --: :.--' - ; ' :
~ :' . . ,: .. .
~72~
noticeably wetted, and gives a dry and soft feeling to the user which is effective in giving a pleasant feeling in use.
The above described embodiments, of course, are not to be construed as limiting the breadth of the present invention. Modlfications, and other alternative con-structions, will be apparent which are within the spirit and scope of the invention as defined in the appended claims.
.
:
:
:
:
:
. .. . :: .
`~ - : '.. , , .: . .
:
.
:: ` ` ` .: ` :
-. : :~ ~ : . .
Claims (14)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A paper diaper, comprising:
a surface layer of fluff pulp in which fibers thereof are not entwined but are aggregated together;
a partition layer having spaced-apart openings therein and being located under said surface, said partition layer being non-absorbent but said openings allowing fluid to fall down therethrough;
a crust layer comprising fluff pulp fibers which are oriented in a longitudinal direction of the paper diaper and are bonded to each other, said crust layer being disposed under said partition layer to receive and diffuse in an oriented manner the fluid falling down through the openings in said partition layer and to retain at least some of the fluid;
a fluff pulp main layer disposed under said crust layer and comprising fluff pulp fibers which are not essentially entwined and bonded to each other;
said main layer having upstanding peripheral edge portions between which said crust layer is disposed;
said main layer being integrally continuous with a lower part of said crust layer and said upstanding peripheral edge portions being integrally continuous with edge portions of said crust layer;
said crust layer being enclosed by said partition layer, said upstanding peripheral edge portions and said main layer; and an outer covering enclosing said layers.
a surface layer of fluff pulp in which fibers thereof are not entwined but are aggregated together;
a partition layer having spaced-apart openings therein and being located under said surface, said partition layer being non-absorbent but said openings allowing fluid to fall down therethrough;
a crust layer comprising fluff pulp fibers which are oriented in a longitudinal direction of the paper diaper and are bonded to each other, said crust layer being disposed under said partition layer to receive and diffuse in an oriented manner the fluid falling down through the openings in said partition layer and to retain at least some of the fluid;
a fluff pulp main layer disposed under said crust layer and comprising fluff pulp fibers which are not essentially entwined and bonded to each other;
said main layer having upstanding peripheral edge portions between which said crust layer is disposed;
said main layer being integrally continuous with a lower part of said crust layer and said upstanding peripheral edge portions being integrally continuous with edge portions of said crust layer;
said crust layer being enclosed by said partition layer, said upstanding peripheral edge portions and said main layer; and an outer covering enclosing said layers.
2. The paper diaper of claim 1, wherein said partition layer comprises a plurality of grooves in a top surface of said crust layer and extending in a longitudinal direction of the diaper, and a fluid resistant covering over the top surface of said crust layer between said grooves.
3. The paper diaper of claim 1, wherein said partition layer comprises a plurality of cavities dented into a top surface of the crust layer, and non-absorbent film covering said top surface except where said cavities are disposed.
4. The paper diaper of claim 1, wherein said partition layer comprises a water resistant layer separate from the crust layer and placed on a top surface of the crust layer.
5. The paper diaper of claim 1, wherein an odor improving agent is mixed in the lower part of the fluff pulp making up the surface layer.
6. The paper diaper of claim 5, wherein said agent is a deodorant.
7. The paper diaper of claim 5, wherein said agent is an aromatic.
8. The diaper of claim 1, wherein said partition layer comprises a fluid resistant coating on said crust layer.
9. The diaper of claim 1, wherein said partition layer comprises an open woven fabric, said openings being formed by interstices between woven elements of the fabric.
10. The diaper of claim 1, wherein said partition layer comprises a fluid impervious film extending over said crust layer.
11. A diaper, comprising:
a surface layer of fluff pulp;
a partition layer having a plurality of openings therethrough, said partition layer being disposed below said surface layer;
a crust layer comprising fluff pulp fibers which are oriented and bonded together, the crust layer being disposed beneath said partition layer;
a fluff pulp main layer below said crust layer;
an outer covering enclosing said layers;
said surface layer comprising fluff pulp fibers which are compacted together;
said crust layer orientated fibers being orientated in a lengthwise direction of the diaper;
said crust layer having grooves in a top surface thereof, said grooves extending lengthwise in said lengthwise direction and extending downwardly only partway through said crust layer;
said partition layer comprising a fluid resistant coating on said top surface of said crust layer between said grooves, said openings extending in said lengthwise direction in register with said grooves;
said main layer comprising fluff pulp fibers which are not entwined and not bonded together;
said main layer being integrally continuous with a lower part of and with side edges of said crust layer;
upstanding edge portions of said main layer enclosing the side edges of said crust layer;
said outer covering comprising non-woven fabric extending over upper and lower surfaces of the diaper; and an odor improving agent being disposed in a lower portion of said surface layer adjacent said partition layer.
a surface layer of fluff pulp;
a partition layer having a plurality of openings therethrough, said partition layer being disposed below said surface layer;
a crust layer comprising fluff pulp fibers which are oriented and bonded together, the crust layer being disposed beneath said partition layer;
a fluff pulp main layer below said crust layer;
an outer covering enclosing said layers;
said surface layer comprising fluff pulp fibers which are compacted together;
said crust layer orientated fibers being orientated in a lengthwise direction of the diaper;
said crust layer having grooves in a top surface thereof, said grooves extending lengthwise in said lengthwise direction and extending downwardly only partway through said crust layer;
said partition layer comprising a fluid resistant coating on said top surface of said crust layer between said grooves, said openings extending in said lengthwise direction in register with said grooves;
said main layer comprising fluff pulp fibers which are not entwined and not bonded together;
said main layer being integrally continuous with a lower part of and with side edges of said crust layer;
upstanding edge portions of said main layer enclosing the side edges of said crust layer;
said outer covering comprising non-woven fabric extending over upper and lower surfaces of the diaper; and an odor improving agent being disposed in a lower portion of said surface layer adjacent said partition layer.
12. A diaper, comprising;
an upper layer of fluff pulp through which fluid can freely pass downwards;
a partition layer below said upper layer, said partition layer preventing passage of the fluid therethrough except through openings in the partition layer, said openings being spaced apart and distributed over the partition layer;
a body of fluff pulp below said partition layer;
said body having an integral top crust layer juxtaposed said partition layer, said crust layer having fluff pulp fibers oriented in a longitudinal direction of the diaper and bonded together to enable the fluid passing downwards through said openings to be absorbed in said crust layer and seep throughout said crust layer in said longitudinal direction by capillary action;
said crust layer having depressions in a top portion thereof extending downwardly from a top surface thereof and only partway through said crust layer;
said depression being in register with said openings;
and said body of fluff pulp having upwardly extending peripheral edge portions extending parallel to said longitudinal direction and enclosing side edges of said crust layer to minimize lateral leakage from said side edges of the fluid absorbed in said crust layer.
an upper layer of fluff pulp through which fluid can freely pass downwards;
a partition layer below said upper layer, said partition layer preventing passage of the fluid therethrough except through openings in the partition layer, said openings being spaced apart and distributed over the partition layer;
a body of fluff pulp below said partition layer;
said body having an integral top crust layer juxtaposed said partition layer, said crust layer having fluff pulp fibers oriented in a longitudinal direction of the diaper and bonded together to enable the fluid passing downwards through said openings to be absorbed in said crust layer and seep throughout said crust layer in said longitudinal direction by capillary action;
said crust layer having depressions in a top portion thereof extending downwardly from a top surface thereof and only partway through said crust layer;
said depression being in register with said openings;
and said body of fluff pulp having upwardly extending peripheral edge portions extending parallel to said longitudinal direction and enclosing side edges of said crust layer to minimize lateral leakage from said side edges of the fluid absorbed in said crust layer.
13. The diaper of claim 12, wherein:
said upper layer is compressed and fibers thereof are arranged tightly; and said partition layer comprises a fluid resistant coating on said top surface of said crust layer and extending over said top surface between said openings.
said upper layer is compressed and fibers thereof are arranged tightly; and said partition layer comprises a fluid resistant coating on said top surface of said crust layer and extending over said top surface between said openings.
14. A diaper for absorbing fluid, comprising:
a surface layer of fluff pulp which is compressed and in which fibers thereof are not entwined but are arranged tightly together, said surface layer allowing the fluid to pass downwardly therethrough;
a partition layer located under said surface layer, said partition layer having a plurality of spaced-apart openings therethrough and distributed thereover, said partition layer preventing passage of the fluid therethrough except through said openings;
a crust layer comprising fluff pulp fibers which are orientated in a longitudinal direction of the diaper and bonded together, said crust layer being disposed under said partition layer to receive and diffuse throughout said crust layer the fluid passing through said openings and to retain at least some of this fluid;
a fluff pulp main layer below and on opposite sides of said crust layer, said main layer comprising fluff pulp fibers which are not essentially entwined and bonded together, and said main layer being integrally continuous with a lower part and side edges of said crust layer;
said main layer having upwardly extending edge portions which bound and enclose said side edges of said crust layer and minimize seepage of the fluid from said side edges;
the fibers of said crust layer having weak orientation and bonding at a bottom portion of said crust layer where said crust layer blends into said main layer;
said partition layer comprising a transparent film of water resistant material coated on an upper surface of said crust layer and extending thereover between said openings;
said crust layer having spaced-apart depressions in said upper surface, said depressions underlying said openings to receive the fluid passing downwardly through said openings and said depression extending downwardly only partway through said crust layer;
an odor improving agent adjacent a bottom of said surface layer;
a layer of water resistant paper under said main layer;
an outer covering of non-woven fabric enclosing said surface layer, said main layer, said crust layer, and said paper layer; and said partition layer, said crust layer, and said main layer interrelating to cause the fluid absorbed by the diaper to be diffused over a wide area of said crust layer with a substantial amount of the fluid being retained in said crust layer, any fluid said crust layer is not able to retain being distributed throughout said main layer which then becomes evenly moistened.
a surface layer of fluff pulp which is compressed and in which fibers thereof are not entwined but are arranged tightly together, said surface layer allowing the fluid to pass downwardly therethrough;
a partition layer located under said surface layer, said partition layer having a plurality of spaced-apart openings therethrough and distributed thereover, said partition layer preventing passage of the fluid therethrough except through said openings;
a crust layer comprising fluff pulp fibers which are orientated in a longitudinal direction of the diaper and bonded together, said crust layer being disposed under said partition layer to receive and diffuse throughout said crust layer the fluid passing through said openings and to retain at least some of this fluid;
a fluff pulp main layer below and on opposite sides of said crust layer, said main layer comprising fluff pulp fibers which are not essentially entwined and bonded together, and said main layer being integrally continuous with a lower part and side edges of said crust layer;
said main layer having upwardly extending edge portions which bound and enclose said side edges of said crust layer and minimize seepage of the fluid from said side edges;
the fibers of said crust layer having weak orientation and bonding at a bottom portion of said crust layer where said crust layer blends into said main layer;
said partition layer comprising a transparent film of water resistant material coated on an upper surface of said crust layer and extending thereover between said openings;
said crust layer having spaced-apart depressions in said upper surface, said depressions underlying said openings to receive the fluid passing downwardly through said openings and said depression extending downwardly only partway through said crust layer;
an odor improving agent adjacent a bottom of said surface layer;
a layer of water resistant paper under said main layer;
an outer covering of non-woven fabric enclosing said surface layer, said main layer, said crust layer, and said paper layer; and said partition layer, said crust layer, and said main layer interrelating to cause the fluid absorbed by the diaper to be diffused over a wide area of said crust layer with a substantial amount of the fluid being retained in said crust layer, any fluid said crust layer is not able to retain being distributed throughout said main layer which then becomes evenly moistened.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000515842A CA1272851A (en) | 1986-08-13 | 1986-08-13 | Paper diaper |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000515842A CA1272851A (en) | 1986-08-13 | 1986-08-13 | Paper diaper |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1272851A true CA1272851A (en) | 1990-08-21 |
Family
ID=4133720
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000515842A Expired CA1272851A (en) | 1986-08-13 | 1986-08-13 | Paper diaper |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1272851A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5509915A (en) | 1991-09-11 | 1996-04-23 | Kimberly-Clark Corporation | Thin absorbent article having rapid uptake of liquid |
-
1986
- 1986-08-13 CA CA000515842A patent/CA1272851A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5509915A (en) | 1991-09-11 | 1996-04-23 | Kimberly-Clark Corporation | Thin absorbent article having rapid uptake of liquid |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4676786A (en) | Paper diaper | |
| CN2247516Y (en) | Disposable body fluid absorption liner | |
| US6458111B1 (en) | Disposable absorbent article | |
| US4282874A (en) | Disposable absorbent article of manufacture | |
| US5728084A (en) | Absorbent article with controlled distribution of liquid | |
| EP1016396B1 (en) | Absorbent article having strike window | |
| EP0556996B1 (en) | Underpad for incontinent patients | |
| KR890002046B1 (en) | Absorbant pad | |
| US6569137B2 (en) | Absorbent incontinence pads | |
| EP0067916A1 (en) | Quilted diaper and sanitary napkin products | |
| IE862900L (en) | All-in-one diaper with branched absorbent pad | |
| GB2087240A (en) | Sanitary napkin with two reservoirs | |
| WO1986007242A1 (en) | Absorbent article | |
| JPH08510665A (en) | Absorbent article having crimped joint for preventing seepage of stain | |
| US6118042A (en) | Absorbent article with controlled distribution of liquid | |
| IE51061B1 (en) | Disposable diapers | |
| IE45552B1 (en) | Absorbent articles | |
| MXPA99003893A (en) | Absorption material having temperature dependent absorption capacity and the use thereof in an absorbent article | |
| US20020007165A1 (en) | Absorbent core for use in a sanitary absorbent article and method for manufacturing | |
| HUT63761A (en) | United, combined fluid-absorbing device | |
| CA1272851A (en) | Paper diaper | |
| JPH11318982A (en) | Absorptive article | |
| JP3427525B2 (en) | Absorbent articles | |
| US6738735B1 (en) | Method of determining the efficiency of an absorbent article having two absorbent layers that each contain a superabsorbent | |
| DE19936154C2 (en) | Flat flexible layer composite |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKLA | Lapsed |