JPH1071660A - Disposable product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a disposable product which is excellent in absorption rate and absorptive capacity. SOLUTION: In a disposable product which contains at least one nonwoven fabric or tissue paper layer stuck to another nonwoven fabric, tissue paper or polyolefin film layer by use of a hot-melt adhesive composition composed of 10-80wt.%, preferably 40-60wt.% of olefin-containing polymer, 10-70wt.%, preferably 30-60wt.% of compatible tacking producing resin, 0-20% of plasticizer, 0-2% of stabilizer, 0-25% of wax, and 1-25% of surface-active agent, the adhesive composition indicates 90 deg. or under contact angle and decrease of about 40 dyne/cm or under surface tension with the surface-active agent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

FIELD OF THE INVENTION The present invention relates to hot melt adhesives for nonwovens and tissue.

[0002]

BACKGROUND OF THE INVENTION Nonwoven fabrics are an entangled network of synthetic or natural fibers or a combination of the two in which individual fibers are mechanically, chemically or thermally bonded together. . Tissue is a very similar material in which the individual fibers are bonded or unbonded to each other. Nonwovens or tissue papers are characterized by their flexibility, porosity and cohesion. Nonwovens are commonly used for a variety of applications, including insulation, packaging, household towels, surgical drapes, medical bandages, and disposable articles such as diapers, adult incontinence products, and sanitary napkins. Have been.

[0003] In many end uses, there is a need to adhere nonwovens or tissue to other supports or members. The second support is another nonwoven, tissue, or dissimilar material, such as a polyethylene film. Generally, hot melt adhesives are used to bond the glulam together. Hot-melt adhesives allow for cost-effective and uptime production because they do not require the evaporation step required for aqueous or solvent-based adhesive systems. For application to nonwovens, suitable hot melt adhesives have good flexibility (handlability), are free of stains or surface bleed, have appropriate viscosity, and use commercially available equipment Must have a set time and an air dry time, and ultimately have acceptable heat aging properties.

Another desirable property for hot melt adhesives, which is particularly important in disposable diapers, sanitary napkins, and bunk pad constructions, is to allow liquid or moisture to penetrate the superabsorbent from nonwoven fibers or to provide a core support. It is the performance of the inflatable hot tilt adhesive. This property is called bleed-through and is desirable for allowing the moisture to escape from the support to the absorbent core as soon as possible after the nonwoven is wet.

[0005] Many hot melt adhesives are hydrophobic and repel moisture rather than allowing moisture to permeate the absorbent core through itself. It is known to use fluorochemical surfactants in certain hot melt adhesives to provide improved bleed through without reducing the absorption rate or capacity of the absorbent. In addition to their use as structural adhesives, hot melt adhesives are used to bond or strengthen the nonwoven fibers together. These hot melt adhesives can also be formulated to provide improved bleed through with fluorosurfactants. However, fluorosurfactants are expensive, are absorbed by the skin, and remain in the body. These constraints make fluorosurfactants unsuitable for disposable nonwovens that come into direct contact with the human body.

[0006]

SUMMARY OF THE INVENTION When used at appropriate levels, the addition of various hydrocarbon and silicone based surfactants to conventional olefin-containing hot melt adhesives suitable for use in nonwovens. Has been found to provide the unexpected benefits of improved fluid absorption rate and fluid spreading (wicking action) and resistance to high humidity and direct immersion.

The present invention relates to (a) 10-80% by weight, preferably
40 to 60% by weight of olefin-containing polymer, (b) 10 to 70% by weight, preferably 30 to 60% by weight of compatible tackifying resin, (c) 0 to 20% of plasticizer, (d) 0 to 0% 2% stabilizer,
at least one non-woven, tissue or polyolefin film layer adhered using a hot melt adhesive composition comprising (e) 0-25% wax, and (f) 1-25% surfactant. A disposable product comprising two nonwoven or tissue layers, wherein the surfactant causes the adhesive composition to have a contact angle of 90 ° or less and about 35-40 dynes / cm or less, preferably 35 dynes / cm or less, more preferably Is 30 dynes /
cm, most preferably a decrease in surface tension of 20 dynes / cm.

[0008] When a droplet is placed on a uniform, perfectly flat solid surface, its shape and the length of time to maintain that shape are determined by three interfacial tensions: the surface tension of the solid and the surface of the liquid. It is determined by the tension and the interfacial tension between the solid / liquid. The angle between the tangent (edge) of the droplet and the solid surface is a calculated value related to the vector sum of the forces. In general, the smaller the contact angle Θ, the more the droplet tends to lose its shape and spread. The addition of a surfactant to the liquid causes a reduction in the surface tension of the droplet.

When a hot melt adhesive is used for a nonwoven fabric structure, the addition of a surfactant to the adhesive causes
The contact angle い か な る of any liquid on the adhesive is reduced. As a result of the presence of the surfactant, the liquid permeates more effectively through the adhesive layer toward the superabsorbent core. Similar results are obtained when a surfactant is added to the hot melt adhesive used to bind or reinforce the nonwoven fibers. At the same time as the contact angle of the liquid decreases, the surface tension also decreases, but this reduction in surface tension also reduces the ability of the nonwoven fabric to penetrate the liquid into the core. Therefore, in producing an adhesive suitable for this application, a balance must be made between the type and amount of surfactant used to provide optimal performance. Optimum performance is 90 ° in disposable products
It is obtained by adding to the hot melt adhesive a type and amount of a surfactant that penetrates at the following contact angles and reduces the surface tension by about 35 to 40 dynes / cm or less, preferably 35 dynes / cm or less. Can be

[0010] The improved hot melt adhesive composition used in the disposable product of the present invention prevents leakage from the absorbent core and allows for the use of thinner absorbent core supports.

A preferred surfactant is the ethoxylate of a monohydric alcohol, which is present in the adhesive in an amount of from 1 to 25% by weight. Ethoxylates of monohydric alcohols are the product of the polymerization of ethylene oxide initiated at the -OH site of the alcohol. The addition of a surfactant increases the hydrophilicity of the hot melt adhesive, rather than causing the surfactant to act as a barrier to liquid penetration, as compared to conventional hot melt adhesives, and Improve properties.

The surfactant used in the present invention includes:
When added to the adhesive composition in a sufficient amount, it imparts improved wicking properties to the adhesive without deteriorating the adhesive properties. Particularly preferred are Petr
Highly crystalline surfactants such as Unithox ™ 480, a product of olite Specialty Polymers Group, Tulsa, OK. Typically, the surfactant is used in an amount of 1 to 25% by weight, preferably 5 to 15% by weight, but the actual preferred range will depend on the particular adhesive system.

[0013] Suitable surfactants include nonionic, anionic, and silicone surfactants. Examples of nonionic surfactants are (i) ethoxylates of C ₁ -C ₁₈ , preferably C ₈ -C ₉ alkyl or dialkyl phenols, such as, for example, the Macol brand name from PPG Industries, Gurnee, Illinois.
Commercially available under DNP-10 (10 mol ethoxylate of dinonylphenol) and Triton X-100 available from Union Carbide (10 mol ethoxylate of octylphenol); (ii) C ₈ -C ₆₀ Ethoxylates of alkyl monohydric alcohols, for example, Huntsman Chemical Co.
Commercially available under the trade name Surfonic L-12-8 (8 mol ethoxylate of dodecanol), and Petr
available under the brand name Unithox480 from the olite Specialty Polymers Group, Tulsa, OK (38 molar ethoxylate crystalline surfactant); and (iii) propylene oxide polymers, such as BASF under the brand name Pluronic from BASF (Ethylene oxide / propylene oxide block copolymers having a _Mn of 200 to 3000); and by partial condensation of benzoic acid with a hydrophilic dihydric or monohydric alcohol having a _Mn of 1000 or less. The benzoate formed, for example, the condensation product of about 3 equivalents of benzoic acid with 4 equivalents of diethylene glycol (commercially available as XP 1010 from Velsicol Chemical).

Suitable anionic surfactants are C ₈ -C ₆₀ alkyl ethoxylate sulfonates, CH _3- (CH ₂ ) _11-14- (O-
_{CH 2 CH 2) 3 -SO 3} - Na +, for example, Avenel S30, available from PPG Industries; C ₈ -C ₆₀ alkyl sulfonates, e.g., Rhodapon available from Rhone Poulenc UB (C ₁₂ alkyl -SO ₃ ^- Na ⁺ ); and alkyl / aromatic sulfonates, eg, structural formula:

Embedded image And commercially available under the trade name Calsoft.

Suitable silicone surfactants are from 500 to 1
Ethoxylates or propoxylates of polydimethylsiloxane having a number average molecular weight of from 0,000, preferably from 600 to 6000, also from Osi Specialties, Danbury, CT under the trade names Silwet L-77, L-7605, and L-7500. And are commercially available as.

Preferred low molecular weight surfactants are those of low molecular weight in order to increase compatibility in the adhesive formulation. The maximum acceptable molecular weight depends on the type of surfactant and other components in the adhesive formulation. Surfactants may be added to any olefin-containing polymer commonly used for disposable applications.

Suitable olefin-containing polymers are those catalyzed by copolymerizable monomers having 15 to 45% by weight of ethylene, such as vinyl acetate, N-butyl acrylate, propylene, methyl acrylate, methyl acrylic acid, acrylic acid, metallocene. It is polymerized with an ethylene-based polymer or the like and a mixture thereof.

Further, suitable polymers include the following monomers: olefins such as ethylene, propylene, butene, hexene, octene, or other α-olefins; vinyl acetate, vinyl propionate, vinyl butyrate, vinyl hexanoate. Homopolymers or copolymers of vinyl monomers such as acrylates; acrylic monomers such as acrylic acid and methacrylic acid, methacrylic acid esters, hydroxyethyl acrylate and the like.

Preferred polymers are ethylene / vinyl acetate copolymers, such as Elvax from DuPont.
It is available under The preferred range for vinyl acetate is 18% to 40% by weight, with 33% by weight being most preferred. Polyolefin polymer, for example,
Also preferred are those available from Huls under Vestoplast.

Other adhesive compositions can be prepared according to the present invention using amorphous polyolefins or mixtures thereof as the base polymer. Amorphous polyolefins are produced by atactic polymerization of polypropylene. The polymerization takes place in the presence of a catalyst comprising a coordination complex of a transition metal halide with an organometallic compound. Solid amorphous propylene oxide has a softening point of about 150 ° C and at 190 ° C
It has a Brookfield viscosity of 1,000-50,000 cps. Suitable commercially available products include Eastman Chemical
s P1010. Amorphous polypropylene and ethylene (APE) copolymers, or amorphous polypropylene and butene copolymers (APB) or amorphous polypropylene and hexene copolymers (APH) are used as base polymers as terpolymers of propylene, butene and ethylene. A
Suitable as PBE). Suitable commercially available products include Re
Trade name Rextac 2315 (APE) from xene; Trade name from Rexene
Rextac 2730 (APB); those sold under the trade names Vestplast 750 and 708 (APBE) by Huls.

[0021] Any blend of the above base materials may be used to prepare the hot melt adhesive composition, for example, a blend of ethylene vinyl acetate and atactic polypropylene.

In all cases, the adhesive is formulated using various amounts of tackifying resins, plasticizers, waxes and / or other conventional additives well known to those skilled in the art.

Tackifying resins useful in the adhesive composition include any compatible hydrocarbon resin, synthetic polyterpene,
Rosin resin, natural terpene and the like may be used. In particular, depending on the particular base polymer, useful tackifying resins include (1) natural and modified rosins, such as gum rosin, wood rosin, tall oil rosin, distilled rosin, hydrogenated rosin, dimerized rosin, (2) glycerol esters and pentaerythritol esters of natural and modified rosins, such as palewood rosin (pale w rosin).
ood rosin), glycerol ester of hydrogenated rosin, glycerol ester of polymerized rosin, pentaerythritol ester of hydrogenated rosin, and phenol-modified pentaerythritol ester of rosin; (3) copolymers of natural terpenes and Terpolymers, for example, styrene / terpene and α-methylstyrene / terpene; (4) polyterpene resins having a softening point of from 80 ° C. to 150 ° C. as determined by ASTM method E28-58T; Generally in the presence of a Friedel-Crafts catalyst,
Produced by polymerization of terpene hydrocarbons such as bicyclomonoterpene known as pinene at relatively low temperatures; and hydrogenated polyterpene resins; (5) phenol-modified terpene resins and their hydrogenated Derivatives, such as resin products formed by the condensation of bicycloterpene and phenol in acidic media; (6) 70 ° C-13
An aliphatic petroleum hydrocarbon resin having a ring and ball softening point of 5 ° C;
(7) aromatic petroleum hydrocarbon resins and their hydrogenated derivatives; (8) alicyclic petroleum hydrocarbon resins and their hydrogenated derivatives; and (9) aromatic / aliphatic or cycloaliphatic Hydrocarbon resins include those marketed by Exxon Chemical Company under the trade names ECR 149B and ECR 179A. For some formulations, 2
A mixture of more than one species is required.

The various plasticizing or extender oils may be present in the composition in an amount of about 20% by weight, preferably 15% by weight, for imparting wetting action and / or adjusting the viscosity. Good. The plasticized or extender oils generally include not only conventional plasticized oils, but also olefin oligomers and low molecular weight polymers, and vegetable and animal oils and their derivatives. Petroleum derived oils that may be used are only slightly used (less than 30% by weight of the oil,
It is a substance having a relatively high boiling point containing aromatic hydrocarbons (in particular, not more than 15% by weight). Alternatively, the oil may not contain any aromatics. The oligomer may be present in an amount from about 350 to about 10,000.
Polypropylene, polybutene, hydrogenated polyisoprene, hydrogenated polybutadiene, and the like having an average molecular weight between Vegetable and animal oils contain glycerol esters of conventional fatty acids and their polymerization products.

Also useful as plasticizers are polar synthetic compounds such as aliphatic and aromatic polyester plasticizers available from CP Hall Co. (Stow, OH). Amidophosphate esters, sulfonamides, and phthalates are also suitable at various concentrations.

Various petroleum derivatives have been used to impart fluidity to the adhesive in the molten state and to provide flexibility to the cured adhesive, and to act as a wetting agent to bind the cellulose fibers. Waxes may also be used in amounts up to about 25% by weight of the composition. The term "petroleum derived wax" refers to both paraffins and microcrystalline waxes having a melting point in the range of 54.4-107.2 ° C (130-225 ° F), as well as low molecular weight polyethylene or Fisher-Tropsch wax. And synthetic waxes such as

[0027] Antioxidants or stabilizers may be included in the adhesive composition in amounts up to about 3% by weight. Among the antioxidants or stabilizers that can be used are high molecular weight hindered phenols and polyhydric phenols, such as sulfur and phosphorus containing phenols. Typical hindered phenols include 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxy-benzyl) benzene, pentaerythritol tetrakis-3 (3 , 5-Di-tert-butyl-4-hydroxyphenyl) propionate, n-octadecyl-3,5
-Di-tert-butyl-4-hydroxyphenol) propionate, 4,4'-methylenebis (2,6-tert-butylphenol), 4,4'-thiobis (6-tert-butyl-o-cresol), 2, 6-di-tert-butylphenol, 6- (4-hydroxyphenoxy) -2,4-bis (n-octylthio) -1,3,5-triazine, di-n-octa-decyl = 3,5-di- tert-butyl-4
-Hydroxy-benzylphosphonate, 2- (n-octylthio) -ethyl = 3,5-di-tert-butyl-4-hydroxy-
Benzoate and sorbitol hexa [3- (3,5-di-ter
t-butyl-4-) hydroxy-phenyl) -propionate]
Is included.

Other additives conventionally used in hot melt adhesives may be added to achieve various properties and to meet specific application requirements, depending on the purpose, small or large amounts. Fillers, pigments, flow control agents, dyes, etc. may be mixed into the adhesive formulation.

[0029] These hot melt adhesives can be prepared using techniques well known in the art. Typically, the adhesive composition is prepared by blending the components in the molten state over a period of about 2 hours at a temperature of about 100-200 ° C until a homogeneous blend is obtained. Various blending methods are known and any method that produces a homogeneous blend is sufficient. The resulting adhesive is characterized by having a viscosity of 50,000 cP at application temperatures below 177 ° C. (350 ° F.). The viscosity used herein is the Brookfield viscosity measured using a Brookfield viscometer model number DV-II using a No. 27 spindle at 10 rpm.

The resulting adhesives of the present invention impart durable bonds to nonwoven or tissue products and meet their unique application requirements (flexibility, non-staining, and mechanical properties). Including processable viscosity). The adhesives described herein have exceptional thermal stability and are distinguished from other moisture-sensitive products. In addition, the hydrophilic nature of the adhesive allows fluid to easily penetrate through the structure.

[0031] The adhesive product may be another support of the product,
Supports such as nonwoven products or tissue by a variety of methods including, for example, tissue, nonwovens or other commonly used supports, such as coating or spraying in an amount sufficient to cause adhesion to a polyolefin film. Can be applied.

The following examples illustrate the composition of suitable hot melt adhesives and their improved wicking properties as a result of mixing the above surfactants.

[0033]

EXAMPLE A sample adhesive was prepared and then contact angle with water,
The surface tension was reduced and the wicking speed was tested. Ingredients: The following ingredients were used: Elvax ™ 460, DuP
ont ethylene / vinyl acetate (EVA) copolymer, containing 18% vinyl acetate (VA), 2.5 (dg / min,
Melt flow index (MF with 2.2kg weight)
(MFI was also measured for the following ingredients); Elvax ™ 265, EVA from DuPont, 28%
Contains VA, has an MFI of 3 (dg / min); Elvax ™
200W, DuPont EVA, containing 28% VA, 2500 (dg / min)
MVA; Elvax ™ 140W, EVA from DuPont
Containing 33% VA and having an MFI of 400 (dg / min); Elva
x 210W, EVA from DuPont, containing 28% VA, 40
Has an MFI of 0 (dg / min); Elvax ™ 40W, DuPon
EVA from T, containing 40% VA and having an MFI of 51 (dg / min); Unitac ™ 100 L, rosin ester tackifier available from Union Camp; Macol ™ DNP-10, PPG
Molar ethoxylate of dinonyl phenol from Nire; Nire
z ™ V2040 HM, a terpene phenolic tackifier available from Arizona Chemical; Zonatac ™ 85
L and 105L with softening points of 85 ° C and 105 ° C respectively
Styrenated terpene from Arizona Chemical; Irganox
TM1010, a hindered phenol antioxidant available from Ciba-Geigy; TritonTM X-100, Union Ca
10 mole ethoxylates of octylphenol available from rbide; Surfonic ™ DNP-100, 10 mole ethoxylates of dinonylphenol available from Huntsman; L12-8 ™, 8 mole ethoxylates of dodecanol available from Huntsman Rate; Pycal ™ 94, ICI
Ethoxylates of phenol available from
ithox ™ 480, an ethoxylated _C30 monohydric alcohol with a molecular weight of 2250 g / mol, Petrolite Specialty Po
available from lymers Group, Tulsa, OK; Escorez ™ 2520, liquid aliphatic / available from Exxon Chemical /
Aromatic C ₅ -C ₉ resins; Nirez (TM) M85NS, Arizona Ch
Aromatic modified polyterpenes available from emical; Nirez
V2040HM, a terpene phenolic tackifier available from Arizona Chemical; Newtac ™ 300,
Phenol-modified polyterpene available from Arizona Chemical; AC-400 ™, containing 13% VA and 14
EVA wax available from Allied-Signal with a viscosity of 595 cP at 0 ° C; Macol ™ DNP-10, PPG Indust
10 mol ethoxylate of dinonylphenol from ries;
Avenel ™ S30, anionic surfactant, sodium sulfonated 3 mole ethoxylate of C _12-15 monohydric alcohol, available from PPG Industries; Rhodapon ™
UB, anionic surfactant, sodium lauryl sulfate,
Available from Rhone Poulenc; Silwet L-77, L-7605 and L-7500, silicone surfactant available from OSI Specialties; Pluronic ™ F38, F68, P65, P85, P6
1 and L44, an ethylene oxide / propylene oxide block copolymer surfactant available from BASF; Unit
ac ™ R98L, a hydrogenated rosin ester available from Union Camp; and Jordapon ™ CI, PPG Industries
Spherical cocoyl isethionate sodium; Aeroso
l MA80, sodium hexylsulfosuccinate from Cytec Industries; Naugard HM22, Uniroyal
Aromatic Amine / Hindered Phenol Blends available from Eastman Chemical Co .;
A tackifier based on dicyclopentadiene, available from Co., Ltd.

Example 1 A sample adhesive composition suitable for forming a nonwoven product from the above raw materials was formulated with the following composition expressed in parts by weight (PBW). The adhesive used as a control contained no surfactant.

[Table 1] The surfactants included in each of Samples DT were changed to the following surfactants indicated by trade names.

[Table 2]

The following procedure was used to test the samples. Contact angle test: Contact angle is measured using a goniometer with a microsyringe to dispense droplets of the correct size and a camera to take a picture of the angle of the droplet in contact with the solid surface. did. The contact angle is measured as the angle between the support and the tangent of the droplet at the interface. The smaller the contact angle, the more the coating will penetrate (suck up) the liquid through the discontinuous adhesive layer.

Surface tension: The surface tension of water was measured using the Dunuoy ring method. Apply 2 g of adhesive to a clean 5 cm ID
Put into a 110ml glass bottle, melt at 135 ° C in an oven,
Then cooled to room temperature. 0.85% sodium chloride solution
12 ml was poured into a dish. The surface tension of the aqueous sodium chloride solution after 15 minutes of exposure to the pure aqueous sodium chloride solution and the adhesive was measured using a KRUS K-14 tensiometer. The difference in surface tension was recorded as the decrease in surface tension (STR).

Liquid wicking area: width 7.62c including adhesive-coated surface
A sample of the support, m (3 inches) × 25.4 cm (10 inches) long, was placed 7.62 cm from the top of the front of Plexiglas ™
(3 inches) position and 7.62 from the top back
Coiled around cm (3 inches). Sample at 22.2 ° C
Conditioned at (72 ° F.) / 50% relative humidity over 24 hours. A 1-liter beaker was poured with a 0.9% aqueous sodium chloride solution dyed red to the 200 ml mark. The sample was placed in a beaker, the liquid was allowed to rise for 2 minutes, and the sample was removed from the beaker, and the total wicking area was calculated (within 10 seconds).

The results of these tests are tabulated to show that the addition of a surfactant increases the wicking area (Sample C),
Contact angle of 90 ° or less (samples A to G, K and M
T), and that the surface tension is reduced by about 35 dynes / cm or less.

[Table 3] Adhesive sample E was chosen as a representative sample for comparison to the control adhesive in a test to measure the bond strength after moisture exposure or water immersion. The adhesive was tested according to the following test procedure.

Moisture test: at a temperature of 149 ° C. (300 ° F.)
The nonwoven fabric of the sample was adhered or bonded to a polyethylene support by applying the above adhesive composition with an applicator at 137.2 m / min (450 ft / min) and 2.66 g / m ² . Two sets of adhesive layers were formed for each adhesive and conditioned for three days: one set at ambient conditions and a second set at 49 ° C.
(120 ° F), conditioned at 90% relative humidity. A rubber-based structural adhesive without surfactant was used as a control. After condition adjustment, 30.48cm /
The adhesive layer was pulled in a 180 ° T-peel mode at a crosshead speed of 12 inches / minute and a chart speed of 5.08 cm / minute (2 inches / minute). The average peel mode of the four tests was recorded, and if there was an adhesive layer failure, the type of failure was recorded instead of the peel strength.

Immersion test: adhesive sample as described above and 28
Parts by weight styrene / isoprene / styrene, 56 parts by weight partially saponified rosin, and 16 parts by weight Maco
l An adhesive layer of a polyethylene support and a non-woven fabric was prepared using a rubber-based adhesive containing a surfactant commercially available under DNP-10. The adhesive layer is 149 ° C (300 ° F),
Formed using a coater at 132.2 m / min (450 ft / min), and 4.5 g / m ² . For each adhesive, one set of adhesive layers was stored at ambient conditions. The second set of adhesive layers was soaked for 1 hour in room temperature deionized water, then drained, and the adhesive layers were tested immediately. 30.48c by Instron testing machine
m / min (12 inches / min) crosshead speed, 5.08 cm /
The adhesive layer was pulled in a 180 ° T-peel mode at a chart speed of 2 inches / minute. The average peel mode of the four tests was recorded, and if there was an adhesive layer failure, the type of failure was recorded instead of the peel strength. The results of both tests are listed in the table below.

[Table 4] The abbreviations for destruction mode are as follows: Adhesive layer breakage from non-woven fabric with some fiber detachment. 2. Adhesive layer breakage from non-woven fabric with significant fiber shedding. 3. Adhesive layer breakage from polyethylene. 4. Cohesive failure mainly to polyethylene. Those bonded using a rubber-based adhesive containing a surfactant fell apart during the immersion test.

Samples conditioned by immersion have a higher bond strength than samples conditioned at ambient temperature and humidity due to softening of the adhesive and matting of the nonwoven. The results of this test show that excellent polyethylene / nonwoven composites are obtained that withstand high moisture and direct immersion despite low contact angles.

Example II Benefits of a Crystalline Surfactant In this example, a crystalline surfactant was used to achieve a low contact angle with water and a low STR. The crystallinity of the surfactant reduces the mobility of the surfactant and the water ST
R has become smaller. Depending on the molecular structure, the crystalline site can be either the hydrophobic or the hydrophilic portion of the surfactant or both. The increase in the decrease in surface tension of water is shown in the table below. In this recipe, each component is included in parts by weight indicated in parentheses.

[Table 5] The crystallization of the surfactant in Examples U and V was determined by Perkin
-Confirmed by DSC measurement performed using Elmer DSC-7. Heat the sample to 150 ° C, hold at that temperature for 5 minutes,
Then it was cooled to room temperature at a rate of 10 ° C./min. The samples were then run at 10 ° C / to determine the crystallinity of the surfactant in the formulation.
Reheated in minutes. The heat of fusion and melting point of the sample were determined in a reheat cycle. Unithox ™ 480 itself exhibits a melting peak at 56 ° C and a heat of fusion of 112 J / g. In adhesive formulations U and V, the melting peak at 53 ° C is observed to overlap the melting peak of the EVA-based polymer. This peak indicates that the surfactant recrystallizes in the formulation (and is therefore recrystallizable).

Example III The following adhesives are examples of high viscosity, high strength, fast curing adhesives suitable for bonding fibers when entangled with other fibers in the nonwoven fabric. These compositions are given in parts by weight in the following table, and the identity of their raw materials is as described above.

[Table 6] For samples AA to DD, 100 g of each sample was placed in a glass bottle for 24 hours.
Maintained at 177 ° C (350 ° F). No phase separation occurred in any of the samples. The solidified mass of each adhesive (approximately 5 cm in diameter and 1.5 mm in thickness) was subjected to 38 ° C (100 ° F / 95% relative humidity).
%) Overnight. No leaching of surfactant occurred. A drop of water was gently placed on the surface of each adhesive by pipette. Adhesives BB-DD exhibited contact angles between 60 ° and 80 °. The contact angle decreases as the droplet stands. Adhesive AA
Showed almost instantaneous wetting of the water droplets. 1000 lbs. Of adhesive AA was prepared on a large scale in a sigma blade mixer, the melt was charged to an extruder and pelletized in water.

All three samples EE-GG were easily wetted by water droplets. The adhesive EE having a low vinyl acetate content produces a harder product than the sample GG.

In summary, the above results show that these adhesives can be used to form nonwoven disposable products. Obviously, various modifications and improvements can be made to the embodiments of the present invention described above without departing from the scope of the present invention as defined in the claims, and the above description is not intended to limit the present invention. Rather, they should be construed as illustrative only.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location B32B 27/12 B32B 27/32 Z 27/18 C08J 5/12 CES 27/32 C09J 11/06 C08J 5/12 CES 11/08 C09J 11/06 D04H 1/58 A 11/08 A41B 13/02 B D04H 1/58 A61F 13/18 310A (72) Inventor Matthew L. Sharaq United States, New Jersey 08823, Franklin Park, Rachel Court 243 (72) Inventor Vinh United States, California 90292, Marina del Rey, Oakwood Apartment P-103, South Via Marina 4105 (72) Inventor Lydia Wagner United States, New Jersey 07921, Bedminster, Encampment Drive 17 (72) Quinton United States, New Jersey 08502, Bell Mead, Monroe Avenue 74 (72) Inventor Gary Reikowitz United States, New Jersey 08822, Flemington, Broad Street 56

Claims (4)

[Claims] (1) 10-80% by weight, preferably 40-60% by weight, of an olefin-containing polymer; (b) 10-70% by weight, preferably 30-60% by weight of a compatible tackifying resin; (c) 0
-20% plasticizer, (d) 0-2% stabilizer, (e) 0-25%
And at least one nonwoven or tissue layer adhered to another nonwoven, tissue or polyolefin film layer using a hot melt adhesive composition comprising (f) 1-25% of a surfactant. A disposable product, wherein the surfactant causes the adhesive composition to exhibit a contact angle of 90 ° or less and a surface tension reduction of about 40 dynes / cm or less. 2. The surfactant is an ethoxylate of a C ₁ -C ₁₈ alkyl or dialkylphenol; an ethoxylate of a C ₈ -C ₆₀ alkyl monohydric alcohol; an ethylene oxide / propylene oxide block copolymer having a _Mn of 200 to 3000; Benzoates formed by partial condensation of benzoic acid with hydrophilic dihydric or monohydric alcohols having a M _n of 1000 or less; C ₈ -C ₆₀ alkyl ethoxylate sulfonates; C ₈ -C ₆₀ alkyl sulfonates; The disposable product according to claim 1, which is an ethoxylate or a propoxylate of an aromatic sulfonate; or polydimethylsiloxane having a number average molecular weight of 500 to 10,000. 3. The disposable product according to claim 1, wherein the surfactant is a crystalline surfactant. (4) 10-80% by weight, preferably 40-60% by weight, of an olefin-containing polymer; (b) 10-70% by weight, preferably 30-60% by weight of a compatible tackifying resin; (c) 0
-20% plasticizer, (d) 0-2% stabilizer, (e) 0-25%
A disposable product comprising an absorbent core adhered or reinforced using a hot melt adhesive composition comprising: (f) a hot melt adhesive composition comprising from 1 to 25% of a surfactant, wherein the surfactant comprises: A disposable product wherein the adhesive composition exhibits a contact angle of 90 ° or less and a decrease in surface tension of about 40 dynes / cm or less.