DE3306843A1 - ABSORBENT PRODUCT - Google Patents

Description

The invention relates to an absorbent product with an integrated structure, with / being in particular around a disposable diaper and a sanitary napkin.

As a first embodiment of the invention, the disposable diaper will be described, while the sanitary napkin will be explained below.

So far, a layer made by blending has been used as the waterproof backing layer for disposable diapers a low density polyethylene with 3 to 5 wt .-% titanium oxide, a PiIm formed from the mixture, was with a basis weight of 20 to 30 g / m, whereupon the PiIm was then embossed. As a result of the impermeability to vapor Such a layer creates a so-called clammy condition around the wearer's buttocks as the inside of the The diaper becomes extremely damp during a long period of use. Such a cramped condition causes reddened skin irritation and a tingling warmth on the wearer's skin surface, and when the diaper is worn at such a stage for a long period of time, such a diaper can even result in a rash on the wearer's skin. The need for a vapor-permeable waterproof layer for a Diaper has already been recognized and proposals have been made regarding the use of porous films, but there was previously no vapor-permeable, water-impermeable PiIm available, which in view of the pilm strength and in particular the resistance to ice, flexibility, economy and moisture permeability put to rest.

The invention is accordingly based on the object of providing an absorbent product of the type mentioned at the beginning.

⁰ OPy Y

art to design that, while avoiding the disadvantages indicated, the development of a clammy condition underneath the top layer with the risk of skin irritation is avoided.
5

This object is achieved according to the invention by the features indicated in the characterizing part of the main claim. With regard to preferred embodiments, reference is made to the features of the subclaims.
. The invention is to be explained in more detail below with reference to the accompanying drawings. It shows in detail:

J ¹ Ig. 1 shows a cross section through a disposable diaper according to the invention,

Fig. 2 shows a cross section through a sanitary napkin according to

of the invention and

Pig. Figure 3 shows a cross section through another embodiment of the sanitary napkin according to the invention.

The disposable diaper according to the invention comprises an integrated: Construction of a vapor-permeable, liquid-impermeable Backing layer 1, an absorbent layer 2 located thereon and a liquid-permeable layer 3 » which rests on the absorbent layer, whereby the vapor-permeable, The liquid-impermeable backing layer is composed of an illm, which is manufactured by the mixing of 100 parts by weight of a polyolefin resin, 28 to 200 parts by weight of a filler; and 10 to 70 % By weight of a liquid or waxy hydrocarbon polymer, whereby the mixture is formed into a film, which is then laterally and / or in the longitudinal direction stretches until it takes on a dimension more than that

1.2 times the original dimension in that direction constitutes, whereby fine pores are formed within the film.

Examples of polyolefin resins which can be used in accordance with the invention are polyethylene high density, polypropylene resins, and linear low density polyethylene resins. These resins can either be used alone or in mixtures of two or more of these ingredients, although preferred is a linear polyethylene resin use low density alone or a high density polyethylene resin alone.

As fillers according to the invention, it is possible to use both inorganic and organic fillers. Examples of suitable inorganic fillers are calcium carbonate, talc, clay, kaolin, silica, diatomaceous earth, Magnesium carbonate, barium carbonate, magnesium sulfate, barium sulfate, Calcium sulfate, aluminum hydroxide, zinc oxide, magnesium hydroxide, calcium oxide, magnesium oxide, titanium dioxide, alumina, Mica, asbestos powder, glass powder, "shirasu" (white sandy precipitate), zeolite, silica, and the like. Among these, calcium carbonate, talc, clay, silica, diatomaceous earth and barium sulfate are preferred.

Examples of organic fillers include cellulose powder, such as wood flour and cellulose powder, which are either alone or as a mixture of two or more ingredients can be used.

The average particle size of the fillers which are used according to the invention is preferably around

pm

less than 30, more preferably less than

around . Yehin

10 and most preferably between 1 and 5 '.

An oversized particle size causes a poor pore density of the stretched film, while an extremely small one Particle size leads to poor dispersibility of the filler in the resin and, accordingly, to a poor processability.

It is desirable to have a surface treatment of the filler perform in order to achieve a better dispersibility of the filler in the resin and thus at the same time also better film stretchability. One treatment the filler with a fatty acid or a metal salt thereof leads to a particularly advantageous result.

The liquid or waxy hydrocarbon polymer used according to the invention can be selected of liquid polybutadiene, liquid polybutene and hydrates of liquid polybutadiene, among which saturated poly » Preferred are hydroxy-substituted hydrocarbons obtained by hydrogenating hydroxy-limited liquids Polybutadienes.

The saturated polyhydroxy substituted hydrocarbons are hydrocarbon polymers in which the main chain has at least 1.5 hydroxyl groups per molecule and are saturated is, or is substantially saturated by hydrogenation. Such polymers are preferably number average Molecular weight (measured by the vapor pressure method) in the range from 400 to 48,000, preferably between 500 and 20,000. An extremely low number average the molecular weight cannot be satisfactory Weather resistance revealed, while an extremely high number average molecular weight s / a poor Flowability of the polymer results, making it difficult to treat the polymer appropriately. The average number the hydroxyl groups per molecule should be 1.5 »or more preferred, 1.8 or more, and most preferably 2.0 to

5.0 be. It is desirable that the hydroxyl groups are present at one or both ends of the main chain or at the end of a long side chain.

Such saturated polyhydroxy-substituted hydrocarbons can be obtained by a known method, for example by the hydrogenation of butadiene-based, liquid polymers, which are obtained by radical polymerization of butadiene alone or together with a copolymerizable monomer using hydrogen peroxide or the like as a polymerization initiator. Isoprene, chloroprene, styrene, methyl acrylate, methyl methacrylate, methyl vinyl ether or the like can be used as a copolymerizable mono-

15 mers can be used.

The hydrogenation can be carried out in the usual way using a nickel catalyst (for example as a reduced Nickel or Raney nickel), a cobalt catalyst, a platinum catalyst, a palladium catalyst, a Bhodium catalyst, a ruthenium catalyst or a Mixture or an alloy catalyst therefrom.

It is to be considered that the introduction of the carbon-hydrogen polymer with a polar hydroxyl group at the end gives beneficial results in the improvement the compatibility of the components of the film with one another.

The polyolefin resin can be mixed with a heat-30 and / or ultraviolet stabilizer, a pigment, a antistatic agent, a fluorescent agent and the like according to a conventional method.

Regarding the proportions of the polyolefin resin, the filler of the liquid or waxy hydrocarbon polymer, it is recommended that the filler be mixed in an amount of 28 to 200 parts by weight while the

liquid or wax-like hydrocarbon polymers are mixed in in amounts of 10 to 70 parts by weight, both based on Ί00 parts by weight of the polyolefin resin.

If the proportion of the filler is less than 28 parts by weight, there cannot be sufficient pores in the stretched film would be formed, while if the amount of the filler exceeds 200 parts by weight, poor kneading ability, poor dispersibility and poor film or sheet formability result, and besides stretched product has low surface strength.

In the manufacture of the waterproof layer according to the invention, the above-mentioned three materials are mixed and a film or layer is formed from the mixture in a known manner. Then, the film or the Layer stretched more than 1.2 times its original dimension in at least one direction to form of fine pores in the film or layer. In the case of uniaxial stretching of the film or layer, a Roll stretching is used, but pipe stretching can also be used to achieve a specific load in a Apply direction (stretching direction).

Such stretching can be done in one step or in two or more steps.

Usually the stretch ratio can result in the desired porosity if stretching in one direction is more than 1.2 times, preferably 1.2 to 4.0 times, and even more preferably 1.2 to 2.0 times the original Dimension in at least one direction of the film.

So ± l1 in the case of uniaxial and biaxial stretching, it is possible to apply a heat treatment to the film to precisely stabilize after stretching. It

it is also possible to carry out a known surface treatment, such as a corona discharge or flame treatment.

The film or layer thus obtained is excellent Water vapor and gas permeability due to the interconnected pores. When using such a film or such a layer as a backsheet for a disposable diaper, must be flexible, strong and economical Care should be taken, and these factors are largely determined by the basis weight of the film or the layer affected. The basic weight is preferred

2
wisely in the range of 20 g / m and most preferred

ο
between 25 "Hid MO g / m. From an economic point of view, it is desirable that the basis weight be lower

than 20 g / m 2, but using currently available techniques such a low basis weight is not possible a sufficiently high film or layer strength for the practical use leads. From the standpoint of strength it is

a basis weight in excess of 50 g / m 2 is desirable, but such a high basis weight is impractical in view of the fact that it is on economy and flexibility is.

Other components of the disposable diaper according to the invention should be described below.

Several layers of paper have long been used as the absorption medium used. In recent times, however, it has become customary to use cellulose flakes that are wrapped in paper or wet strength paper, to be used for reasons of mass production and economy. These conventional absorbent media can be used in the disposable diaper according to the invention are, however, in order to intensify the effect, it is desirable to use a novel structure, according to which a superabsorbent polymer in the

Sorption medium is introduced, so that of this Medium absorbed urine is held therein, even if the body weight of the wearer is placed thereon. As a super absorbent It is advantageous to use polymers, for example Aquakeep from Seitetsu Kagaku KK.

Fiber fleece is usually used as a liquid-permeable Layer 3> which covers the diaper surface that comes into contact with the wearer's skin. In order to achieve the object on which the invention is based, is it is desirable to employ a liquid-permeable layer capable of preventing the absorbed Liquid neither emerges from the absorption medium. For this purpose, a hydrophobic one is advantageously used Fiber fleece is used, which mainly consists of polyester fibers or Pdlyolefin fibers. Others too Techniques such as those in Japanese Utility Model 11212/1981 and Japanese Patent Application Laid-Open 123745 / Wi may be beneficial for this purpose

20 find use.

In addition to the basic structural features mentioned above, it is also possible to use other known features, . such as a pressure-sensitive adhesive tape as a diaper holder or the attachment of an elastic element to prevent liquid leakage. These devices can easily be used with the disposable diaper according to FIG Invention to be connected.

The invention will be explained in further detail below with reference to various specific examples, but these examples are not intended to limit the invention. In the examples, the term "% ⁿ weight savings ent, unless otherwise stated.

Preparation 1 (Manufacture of saturated polyhydroxy substituted Hydrocarbon)

3kg of commercially available polyhydroxypolybutadiene (R-4-5 HT manufactured by Arco Inc., number average molecular weight (Mn) = 3110; OH group = 0.82 meq / g; cis-1,4- = 15%; trans- 1.4- = 58 % \ vinyl = 2? %) , 3 kg of cyclohexane and 300 g of a catalyst made of ruthenium (5%) on a carbon support (a product by Japan Engelhard Go.) Were placed in an autoclave with a capacity of 10 1 was entered and after the interior of the system had been flushed with purified argon gas, high-purity hydrogen gas was introduced into the autoclave, and heating was started at the same time. The steady state conditions (internal temperature = about 100 ^° G; internal pressure = about 50 kg / cm) were reached in about 30 minutes. The Seaktionssystern was left to stand under these conditions for about 15 hours, whereupon the

15 hydrogenation reaction was observed. Following this

the polymer was refined and dried in the usual manner.

The polymer obtained was waxy, and so was the IR absorption spectrum analysis showed it to be a saturated hydrocarbon polymer, essentially free of double bonds. The -OH group content of the hydrate was 0.8 meq / g.

Preparation 2 (Manufacture of saturated polyhydroxy-substituted Hydrocarbon)

The hydrogenation was carried out in the same manner as this has been described for the preparation 1, with the exception that a liquid polybutadiene G-2000 (manufactured by Nippon Soda KK, molecular weight = 2000) as polyhydroxypolybutadiene was used. The polymer obtained was liquid and had an iodine value of 5 g / 100 g, a hydroxyl value of 4-4 KOH mg / g and a viscosity of 775 poise

30 ⁰ C.

example 1

20 kg of high density polyethylene resin (Novatek ER-002; "Novatek" is a registered trademark of Mitsubishi Kasei Kogyo KK) and 5 kg of saturated polyhydroxy substituted hydrocarbon (the same as obtained in Preparation 2) were stirred and placed in a Henschel Mixer mixed, whereupon 25 kg of calcium carbonate (average particle size 1.2 microns, treated with a fatty acid) was added, followed by further mixing with stirring.

The mixture thus obtained was additionally mixed and granulated by means of a twin screw mixer DM-65 (manufactured by Nippon Seikojo KK).

The product was subjected to blown film extrusion using an extruder of 40 mm in diameter to form

m.
of a 70 Ai / thick film. The extrusion conditions were like

20 follows:

Cylinder temperature: 170-190-210-230 ⁰ C Preßkopftemperatur: 230 ⁰ C

Take-up speed: 8 m / minute, blowing ratio =

flat width »314 mm

The obtained film was uniaxially stretched by means of a roll stretcher under the following stretching conditions:

XQ stretching temperature: 80 ⁰ G

Draw ratio: 2.7 times the original

length

Stretching speed: 11.0 m / minute

The stretched film was sufficiently productive and satisfactory

• ^ bleached. He was also evenly stretched, and the surface looked good.

Using the porous film thus obtained as a back :; Ghi.eht a disposable diaper was made in the following manner. A superabsorbent polymer (Aquakeep, manufactured by Seitetsu Kagaku KK) was evenly between Layers of pulp flakes at a rate of 70g / m distributed to form an absorbent medium with a

Basis weight of 300 g / m. * This layering was made with wet strength Wrapped in paper. The coated layer was applied to the backing layer and by means of a nonwoven fabric

(Basis weight 20 g / m), which is mainly made up of hydrophobic fibers, in particular ES fibers (a product by Chisso KK) composed, covered, whereupon the individual components are finally combined into a uniform object with a tape attached to it

15 became.

Example 2

20 kg of a linear low density polyethylene resin (Ultzex 2021-NF, where "Ultzex" is a registered symbol of Mitsubishi Sekiyu Kagaku Kogyo KK) and 5 kg of saturated polyhydroxy substituted hydrocarbon according to preparation 1, were stirred and mixed in a Henschel mixer, whereupon 25 kg of calcium carbonate (average Particle size 1.2 -; treated with fatty acid) was added, followed by an additional mixture below Stir."

The obtained mixture was further mixed and granulated by a twin screw mixer DSM-65 (manufactured by Nippon Seikojo KK).

The resulting product was blown film extrusion using an extruder having a diameter of 40 mm to form a 70 yu, -thick film. The ex-

COPY]

trusion terms were as follows:

Cylinder temperatures: press head temperature: Recording speed:

170-190-210-230 200 ⁰ C

8 m / minute, blow ratio = 2.0, flat width = 314- well

The resulting PiIm was uniaxially stretched with the aid a roller stretcher under the following conditions:

Draw temperature: draw ratio:

Stretching speed:

80 ⁰ C

2.5 times the original length

11.0 m / minute

The stretched film was porous, sufficiently bleached, and uniformly stretched, and the surface looked good.

Using this porous film as a backing sheet, a disposable diaper was manufactured in the same manner as that in Example 1 has been described.

Examples 3 to 7

Purue Ji'ilmo were made in the same way as this was described in Example 1, but the proportions of the high-density polyethylene ^ the filler and of the saturated polyhydroxy-substituted hydrocarbon were changed as shown in Table 1. Under Using these porous films as the backing layer, disposable diapers were made in the same manner as described in Example 1, manufactured.

Examples 8-10

Using the hydrocarbon polymer obtained according to Receiving preparation 1, porous films were made in the same

Prepared as described in Example 1, except that the draw ratio was changed, as difi £ is shown in Table 1. There were disposable diapers in prepared in the same manner as in Example 1 using the respective porous films as the backing layer.

Examples 11 to 12

Porous films were obtained in the same manner as set forth in Example 1, except that talc was used (MS Tale, a product of Japan Talc Co.) or diatomaceous earth were used as fillers. Disposable diapers were made in the same manner as in Example 1, using the porous films as a backing layer. 15th

Examples 13-15

Porous films were obtained by the method of Example 1, but with the proportions of the linear polyethylene low density, filler and hydrocarbon polymer were changed as shown in Table is listed. Disposable diapers were made in the same manner as described in Example 1 below Use of the porous films as a backing layer.

Examples 16-18

Porous films were made in the same manner as described in Example 2, using liquid polybutadiene (Nisso PB-G, available from Nippon Soda KK) or liquid polybutene (Nisseki Polybutene HV-300, available from Nippon Sekiyu Kagaku KK) as a liquid hydrocarbon polymer and using calcium carbonate or talc (MS Tale, available from Nippon Talc KK) as a filler. Disposable diapers are made in the same way.

provides, as described in Example 1, under Ver,

application of the porous films as a backing layer.

Comparative examples 1 to 3

Porous films were obtained in the same manner as described in Example 1, with the exception that that no hydrocarbon polymer was added to the blend; and that the draw temperature and draw ratio was changed. Using these porous films as backing sheets, disposable diapers were made, accordingly the procedure according to example 1. 10

Comparative Examples 4-6

Porous films were obtained in the same manner as described in Example 2, except that no hydrocarbon polymer was used was added to the mixture and that the stretching temperature and the draw ratio were changed; became. Disposable diapers were made in the same manner as as described in Example 1, using the porous films as the backing layer.

The properties of the films obtained in Examples 1 to 18 and Comparative Examples 1 to 6, the angular formability and the test results and their applicability are compiled in Table 1. Similar evaluations were also employed on a disposable diaper made using a commercially available one available backsheet and another disposable diaper made using two layers commercially available ring-shaped diapers made of bleached cotton cloth with commercially available wool flannel and a diaper cover. The results are also shown in Table 1 (Comparative Examples 7 and 8).

The characters indicated in the column headed "Composition" in Table 1 are defined in Table 2.

The values shown in Table 1 were made according to the following Procedure determined.

1) strength

5 a) tensile strength:

A test piece with the dimensions 10 140 mm was placed in the side Direction placed on the sample film and at a speed of 300 mm / minute with pulling intervals of 100 mm using a Tensilon tensile strength meter pulled, and the maximum load was given as tensile strength.

b) Tear strength:

A 30 60 mm test piece was in the stretching direction

1> of the sample film and with a 30 mm slot provided in the middle part of the shorter side of the test piece. The tear strength was measured by the Use of the Tensilons tensile strength meter. the The tear speed was set at 300 mm / minute.

2) moisture permeability

ο
A-Og / m ¹¹ 'of fluff pulp was wrapped with a paper and formed into a 10 × 10 cm layer. This sheet was placed on an aluminum plate, and then 20 ml of a physiological saline solution was dropped so that it was evenly distributed over the entire sheet. Then the aluminum plate and the layer were covered with a 12 χ 12 cm sample film, and the four sides were secured with vinyl tape.

30. hold. The prepared test piece was attached to the wall (acrylic plate) of a constant temperature water tank at 30 G, and 2 hours later, the changes in weight were measured. The measurements were carried out at 20 ^° C. and 60 % relative humidity.

3) Use test

The manufactured disposable diapers were tested by seven test

babies continuously for a week (for a test)
inserted, and the condition of the diaper rash and
other difficulties encountered during the test period were observed. If the test babies because of
poor health (such as diarrhea)
Suffering from a blown diaper, these test babies were removed from the test results during the course of the test. The tests were carried out during a period from June to October.

Composition (*)

Stretching conditions

strength

g ^ 1OO cm χ

Polyolefin- Filling- Carbon- Temperature- Stretch- PiIm- Tensile- _ Tear-Resistance- ₂ ' _hours resin medium water- ( ⁰ C) behavior- thickness strength Cg)

stoffροΓν- nis (/ um) speed

Moist- Flexi- Veg- Remarkable- bilicity throws urgency diaper

formability and use test

meres

D - 1

50

C - 2
10

2.7

220

1.6

one in seven babies had mild heat pimples

A - 2
40

B - 1
50

C - 1
10

2.5

28 140

1.7

all seven babies showed no deviation

A - 1
45

B - 1
50

C - 2
5

2.7

38 240

1.2

two out of 7 babies suffered and had slight heat pimples:

A-1 B-1 0-2
. 30 50 20

2.7 36

136

A-1 BT C - 2
70 20 10

2.7 35

256

0.2

3 out of 7 babies'. <· ■ · 'had one ^: >,'; Diaper from s chi ag, '<similar. Prickly heat. ,

A-I B-1 0-2

35

2.7 37

233

0.5

A-1 B-1 0-2
30 60 10

2.7 33

148

half of the diapers examined were cracked during the use test

: Part by weight

Table 1

Composition (*)

Stretching conditions

strength

° * / 100 cm Polyolefin filler carbon temperature stretch film tensile tear strength-2 '£

Resin aitfeel water- ( ⁰ C) behavior- thickness strength Cg)

material polymer

(/ um) speed

^/ Cs)

Feuchtig- Flexi- Weg- Pear through- mobility throwing urgency diaper

formability and use test

C.

A - 1
40 B - 1
50 0 -
10 1 2 80 2.7 35 215 9 1.4 UBgIi
shape:
ge st: > »»
I » Il Il π 2 80 1.5 4-5 241 12.5 0.6 Il > »
»»
J
>>> Il I! It 1 80 1.2 50 289 13.3 - 0.2 r>
> » It B - 2
50 σ -
10 1 80 2.7 35 219 7.1 1.3 11th B - 3
50 c -
10 80 2.7 36 231 7.8 1.4 A - 2
45 B - 1
50 c -
5 80 2.5 30th 183 9.5 1.8 A - 2
55 B - 1
35 G -
10 80 2.5 30th 195 15.2 0.4

A-2 B-1 G-1
60 10

80

2.5

29

120

5.6

2.0

25% of the examined Vindeb. were during the Use tests cracked

A-2B-2 0-3
50 10

80

2.5

30th

145

1.9

Composition (*)

Stretching conditions

strength

Heat setting | 3 _do ^ e ()

Moist, flexible, path, clearance urgency diaper

Polyolefin Filling Carbon Temperature Stretching Film Tensile SeL ^ ou ^^ hours resin medium water (C) ratio- thickness strength (g)

stoff-Dolv- - nis (/ um) keit

Comparative examples:

1 A - 1 B - 1st
50 50

110

4.0

25 134

1.5

Geb ^ also-

A -
40 2 B - 3
50 meres 3 80 2 , 5 31 (G) 10 , 3 2 , 2 17th It B - 1
50 C -
10 4th 80 2 , 5 30th 148 9 ,1 1 ,8th 18th C -
10 154

the diaper tore during its manufacture

2 Il It 110 4.0 35 165 4.5 1.2 the diaper tore
while d. Usage? -
testes; ^l «. ' 3 Il It 110 6.0 25th 126 2.4 1.6 «<■
the diaper tore '· «*
during the
Manufacture ', "" « 4th A - 2
50 π 100 6.0 25th 102 3.3 1.7 tf
ι ι <
U te «
X f
* VJl Il M. 100 6.0 33 124 4.7 1.5 The diaper tore%, v
during the '.''<
Most used «, /» ',

*: Part by weight

Tabel

Damp - Fl ex - Path - Remarkable mobility throws urgency diaper

Composition (*)

Stretching conditions

strength

sr / 100 cm χ polyolefin filler carbon temperature stretch film tensile tear strength §g _hours

resin medium water (C) ratio- thickness strength (g)

material polymer

(/ um) speed ⁷ '(g) malleability u.
Usage test

B 50

100

6.0

1.1

the diaper tore
during the use test

26 0.03 5 out of 7 babies
had diaper rash,
similar Heat pimples

1.6

of 7 babies
suffered from
slight heat pimples

Usage of a han · delsübl. avail. watertight *

Use v. 2 layers:

j where rip; at.

! u. finer

available ^ Wiält

deckjing

1 "

J *

Part by weight

Table 2

Sign meaning

A-1 high density polyethylene, Novatek EEO02 (Mitsubishi Kasei Kogyo)

A-2 linear low density polyethylene, Ultzex 2021-NF (Mitsui Sekiyu Kagaku)

/ | q B-1 calcium carbonate, average particle size = 1.2 / u ^f "'treated with fatty acid

B-2 Talc, MS Tale (Japan Tale) B-3 Diatomaceous earth

C-1 wax-like hydrocarbon polymer, 15 produced by hydrogenation of Hydroxy1-be -

bordered polybutadiene (preparation 1)

C-2 liquid hydrocarbon polymer made by the hydrogenation of hydroxyl-capped Polybutadiene (preparation 2)

C-3 liquid polybutadiene, Nisso PBG

(Nippon Soda)

C-4 liquid polybutene, Nisseki polybutene HV-300 (Nippon Sekiyu Kagaku)

From Table 1 there is an obvious difference in the film flexibility between Example 1 according to the invention and Comparative Examples 1 to 3- It is fixed

30 notify that in the cases of the comparative examples (known paper diapers) difficulties during manufacture occur and the diapers, even if well shaped, will tear during use. Example 2 is a diaper using a linear polyethylene resin lower

35 density. The difference in film flexibility from Comparative Examples 4 to 6 is evident. The diapers according to Examples 3 to 7 were produced

using a high-density polyethylene and changing the proportions of the resin, the filler and the hydrocarbon polymer. The limit of the mixing ratios the respective three components can be derived from these examples. In Examples 1 and 8 through 10, the I film working conditions were changed to to vary the thickness of the porous film produced. In these examples, though, there is an improvement in film strength is to be noted, the flexibility and the Moisture permeability reduced. Thus, the allowable limits of film thickness can be determined from these results. Examples 11 and 12 are cases in which Talc and diatomaceous earth were used as fillers. It is found that the films obtained in these examples have properties equal to those of the film of Example 1. In examples 2 and 13 to 18, porous films were made using linear low density polyethylene, and the Diapers were similarly made using these films. It should be noted that linear polyethylene low density to high density polyethylene in terms of flexibility and moisture permeability of the film is preferable. Comparative Example 7 is a disposable diaper made using a commercially available backing layer. 5 of the 7 babies who wore these diapers had after 2 days of use Diaper rash. Comparative Example 8 is a diaper (Baby pants), made from commercially available wool. In the use test, two pieces of commercially available diaper were made from annular bleached cotton cloth hereby used. All use tests and the changing times of the diapers were carried out by the respective mother of the test babies left.

From the above results, it is found that the disposable diaper according to the invention an excellent practical

Has usability.

The absorbent product according to the invention can also be designed as a sanitary napkin. If the invention as If a sanitary napkin is used, it is preferable to use a liquid rubber in the polyolefin resin for the backing layer of the liquid or waxy hydrocarbon polymer.

The sanitary napkin is shown in Figs. Fig. 2 is a schematic representation of a cross section of a Embodiment of the sanitary napkin according to the invention. the Sanitary napkin comprises 1. an absorbent layer 13, which consists of individual layers of cotton-like cellulose, a water absorbing paper 14 and a hey onf as er cloth 15, 2. a water-repellent layer 12, which is is a porous film made by melt molding a composition with a polyolefin resin, a filler; and a liquid rubber, and then stretching the molded product with the bottom being the sides and a part of the upper surface of the absorbent layer is covered with the water-absorbent layer 12, and 3. a surface layer 11 that covers the whole.

Fig. 3 is a schematic representation of the cross section another embodiment of the sanitary napkin according to the invention. The sanitary napkin comprises 1. the absorbent layer 13, which is a single layer of the cotton-like one Cellulose acts, the water-absorbent paper 14 and the rayon fiber layer, 2. the surface layer 11, the covering the upper surface of the absorbent layer; and 3. the water repellent layer 12 which is is the above-mentioned porous film covering the bottom, sides and ends of the absorbent layer, wherein the water-repellent layer 12 by means of a hot melt adhesive 16 on the inside of the ends of the surface layer 11 is attached to this layer 11.

Lie absorbent layer used in the present product is used generally contains a polymer having a high water absorption property as well as cotton-like cellulose 13, the water-absorbent paper 14, and the rayon fiber layer 15.

The product is characterized by a porous film that is impenetrable for human secretion, however is permeable for steam to obtain the film, by melt molding the composition the polyolefin resin, a filler and liquid rubber, whereby the molded product is subjected to a stretching treatment, which is then used as a water-repellent layer. As the polyolefin resin and filler, the above-mentioned embodiments can be used. Liquid polybutadiene and liquid polybutene, for example, can be used as liquid rubber can be used. From the viewpoint of film-forming properties and the strength of the stretched one Product, the mixing ratio is preferably 100 parts by weight of the polyolefin resin to 28 to 200 parts by weight of the filler and 10 to 70 parts by weight of the liquid rubber. This is due to the stretching treatment of the film Draw ratio at least 1.2 in at least one direction. The porous film thus obtained has open pores and accordingly has a high vapor permeability and is resistant to water pressure, with no possibility of penetration for human secretion. Preferably, a large amount of human vaporizes Secretion through the bandage that is not in contact with the body. A porous film with water vapor permeability (according to ASTM E 26-66 (E)) of at least 1000 (g / m χ 24 hours) and preferably of at least 2000 (g / m 24 hours) is used. If a film with a water vapor penetration rate of less than 1000 (g / m χ 24 hours) is used, a large amount of the

human secretion in the bandage. Accordingly "owns Such a film has little effect on reducing stuffiness, and the importance of using one porous film as a water-repellent layer is decreased.

Example 19

5kg of liquid hydroxyl-limited polybutadiene (trademark Poly bd, R-4-5HT, a product of the Idemitsu company Sekiyu Kagaku KK) became 20 kg of high density polyethylene resin (Trademark Novatec BROO2, a product of Mitsubishi Kasei Kogyo KK) was added, and the mixture was stirred in a Henschel mixer. Then 25 kg of calcium carbonate (average particle diameter: 1.2 λι ·, treated with fatty acid) added and the whole thing was stirred up.

The resulting mixture was mixed in a double-screw mixer DSM-65 (a product of Ninon Seiko-sho KK) was kneaded and pelletized. The pellets were blow molded, with the help of an extruder with a diameter of

4-0 mm to form a 70yu · 'thick film. The extrusion conditions were as follows:

Cylinder temperatures: Take-off speed

Press head temperature:

150-180-180 ⁰ C

4 m per minute blow-up ratio = 1.3, flat width = 300 mm 18O ⁰ C

The resulting film was monoaxially stretched using a roll stretching machine.

The stretching conditions were as follows:

Drawing temperature: drawing ratio: drawing speed:

100 ⁰ C 2.2 4.4 m / minute

Thus, a sufficiently bleached porous film was obtained. The porous film had a good surface appearance and was free from uneven stretching.

A sanitary napkin as shown in Fig. 2 was made using the porous film as a wasffir-repellent Layer.

Examples 20 to 25

Porous films were prepared in the same manner as in Example 19 except that the stretching temperature and the draw ratio as shown in Table 3 were used. Sanitary napkins were made using of the obtained porous films as a water-repellent layer.

Comparative Examples 4 and 5

Porous films were made in the same manner as in Example 19 except that liquid rubber was not used and the stretching temperature and the draw ratio according to the information in Table 3 were used became. Sanitary napkins were manufactured in the same manner as in Example 19 using the obtained ones porous films as a water-repellent layer.

Comparative example 6

Sanitary napkins were made in the same manner as in Example 19 using one sheet consisting of made of a layer structure of paper and polyethylene film ("poly-lami water-repellent paper") as a water-repellent Layer.

Film thickness, water vapor, permeability and flexibility that in Examples 19 to 23 and Comparative Examples 4 to 6 obtained films were measured, and the results are compiled in Table 3.

In contrast to conventional sanitary napkins, the napkins according to the invention have the advantage that a part of the human Secretion is evaporated through the water-repellent layer of the bandage, as a water-repellent layer porous film is used, which is impenetrable for human secretion, but permeable to steam, so that accordingly, there is no stuffiness or uncomfortable feeling while wearing. Beyond that Difficulty such as a rash or irritation

15 decreased due to the stuffiness.

Tabel Stretching conditions

Temp. Stretching ratio (C; ratio

Film thickness

Water vapor * permeability g / m χ 24 hours

flexibility

Remarks

Lp "iel

2.2

1.5 1.2 2.2

35 45 50 36 37

2530 1920 1250 2700 2910

O 0

match example

2.2 3.0

34- 2170 30th 2010 30th 330

the films were torn

the water-repellent layer of a conventional one Bandage

Water vapor permeability was determined according to ASTM Ξ26-66 (E)

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Claims (11)

Patent claims: 1. Absorbent product with an integrated arrangement of a liquid-impermeable backing layer, an absorbent medium located thereon and a liquid-permeable layer which is placed on the absorbent Medium rests, characterized in that the backing layer consists of a porous, vapor-permeable, liquid-impermeable Film made by mixing 100 parts by weight of a polyolefin resin, 28 to 200 parts Parts by weight of filler particles and 10 to 70 parts by weight of a liquid or wax-like hydrocarbon polymer or a liquid gum, whereupon the mixture is formed into a film that is then wrapped around the 1.2 times the original dimension in at least is stretched in a surface direction to form fine pores in the film. 2. Absorbent product according to claim 1, characterized characterized in that the polyolefin 10 resin is a high density polyethylene. 3. Absorbent product according to claim 1, characterized in that the polyolefin resin is a linear low density polyethylene resin. 4. Absorbent product according to claim 1, characterized characterized in that the film consists essentially of 30 to 55% by weight of the resin, 35 to 55% by weight of the filler and 5 to 20% by weight of KohlftnwgEtffirfsboff ~ 20 polymer. 5 · Absorbent product according to claim 1, characterized characterized in that the film consists essentially of about 40% by weight of the resin, about 50% by weight of the resin Filler and about 10% by weight of the hydrocarbon polymer. 6. Absorbent product according to claim 1, characterized in that the polyolefin resin is selected is from the group consisting of low density polyethylene and high density polyethylene, while the hydrocarbon polymer is selected from the group consisting of polybutadiene, polybutene and saturated hydroxy-substituted Hydrocarbon polymer obtained by hydrogenation of hydroxy substituted liquid polybutadiene 35 with from 1.5 to 5 hydroxyl groups per molecule, the Hydrocarbon polymers have an average molecular weight of from 400 to 48,000. 7. Absorbent product according to claim. 6, thereby characterized in that the ulm is 1.2 to 4.0 times the original dimension in at least one surface direction is stretched. 8. Absorbent product according to claim 6, characterized characterized in that the filler particles are a par- ywtn Particle size in the range from 1 to 5. 9 · Absorbent product according to claim 6, characterized in characterized in that the film has a basis weight from 20 to 50 g / m. 10. Absorbent product according to claim 1, characterized in that it is a disposable diaper acts. 11. Absorbent product according to claim 1, characterized in that it is a sanitary napkin 20 acts.