JP6144965B2 - Hot melt adhesives and disposable products - Google Patents

Description

  The present invention relates to hot melt adhesives and disposable products.

  Conventionally, disposable diapers, sanitary napkins, pet sheets and the like have been frequently used as disposable products. In such a disposable product, a moisture-permeable film is disposed on a portion that comes into contact with the skin, thereby preventing a user or pet from being peeled off. The moisture permeable film is provided with moisture permeability by providing fine pores. A moisture-permeable olefin resin film or the like is used as the moisture-permeable film. The moisture permeable film is bonded and integrated with a base material (nonwoven fabric, paper, etc.) constituting a disposable product by a hot melt adhesive.

  In a disposable product, when the hot melt adhesive oozes out from the moisture permeable film, the hot melt adhesive directly contacts the skin of the user or pet, causing a rash. Therefore, the hot melt adhesive is required not to exude from the moisture permeable film.

  Further, even when the hot melt adhesive protrudes from the moisture permeable film, the hot melt adhesive comes into direct contact with the skin of the user or pet, causing rash. Therefore, when a hot melt adhesive is applied to an adherend such as a substrate or a moisture permeable film by spraying (spraying machine), it is necessary to accurately apply a desired amount of the hot melt adhesive at a desired position. There is. Therefore, sprayability is also required for hot melt adhesives.

  At the time of application of the hot melt adhesive, the hot melt adhesive is held in a molten state in the tank, and then sequentially discharged by spraying. Therefore, it is also required that the hot melt adhesive does not decompose or deteriorate by heating in the tank.

  In the gathered portion of the disposable product, the stretched rubber is bonded and integrated with a hot melt adhesive. Such a hot melt adhesive is in a state in which shear stress is always applied. Therefore, it is necessary for the hot melt adhesive to be able to bond and integrate the base material and the rubber even when shear stress is applied. Therefore, the hot melt adhesive is also required to have a high adhesion holding force. In the present invention, the “adhesion holding force” means the adhesive force of the hot melt adhesive in a state where shear stress is applied to the hot melt adhesive.

  Patent Document 1 contains a base polymer composed of an amorphous propylene / ethylene random copolymer having a number average molecular weight of 500 to 20000 and an ethylene content of 10 to 80% by weight, and waxes. Olefin-based hot melt adhesives have been proposed. This olefin-based hot melt adhesive has excellent adhesion to a moisture-permeable olefin-based resin film.

  However, olefin-based hot melt adhesives have low adhesion retention and cannot be used for gathered parts of disposable products. Therefore, it is necessary to separately prepare another adhesive for bonding the gathered portions, and the manufacturing process becomes complicated.

  On the other hand, a hot melt adhesive in which a styrene block copolymer is added to an olefin resin has been proposed in order to improve the adhesion retention of the olefin hot melt adhesive. For example, Patent Document 2 contains 10 to 80% by weight of an α-olefin resin, 1 to 35% by weight of a styrene-ethylene-propylene-styrene block copolymer, and 20 to 60% by weight of a tackifier resin. A hot melt adhesive is disclosed. However, such hot melt adhesives have low compatibility and low thermal stability, and thus are easily decomposed and deteriorated by heating in the tank.

JP-A-5-148465 Japanese Patent Laid-Open No. 4-77591

  The present invention does not ooze out from the moisture permeable film, has a high adhesive retention, is excellent in sprayability, has excellent thermal stability, is not easily decomposed or deteriorated by heating in a tank, and has a long time. Provided is a hot-melt adhesive that hardly causes thermal deterioration even when continuously heated.

  The hot melt adhesive of the present invention includes an ethylene-octene copolymer, a thermoplastic elastomer containing a styrene-ethylene-butylene-olefin crystal block copolymer and / or an olefin crystal-ethylenebutylene-olefin crystal block copolymer, and And a tackifying resin.

  The hot melt adhesive of the present invention contains an ethylene-octene copolymer. The ethylene-octene copolymer is a copolymer of ethylene and octene, and may be a random copolymer or a block copolymer.

  An ethylene-octene copolymer has a high melt flow rate (MFR) ethylene-octene copolymer and a low melt flow rate from the viewpoint of maintaining high adhesive retention of a hot melt adhesive and improving sprayability. It preferably contains an (MFR) ethylene-octene copolymer. Specifically, the ethylene-octene copolymer includes an ethylene-octene copolymer having a melt flow rate of 500 to 1250/10 minutes and an ethylene-octene copolymer having a melt flow rate of 15 to 30 g / 10 minutes. It is preferable to contain a coalescence. The melt flow rate of the ethylene-octene copolymer is a value measured under conditions of 190 ° C. and 2.16 kgf (21.2 N) in accordance with ASTM D1238.

  Examples of commercially available ethylene-octene copolymers include “AFFINITY GA1875”, “ENGAGE 8407”, and “INFUSE 9807” manufactured by Dow Chemical.

  The hot melt adhesive of the present invention contains a thermoplastic elastomer. The thermoplastic elastomer includes a styrene-ethylene-butylene-olefin crystal block copolymer and / or an olefin crystal-ethylenebutylene-olefin crystal block copolymer. It contains an ethylene-octene copolymer and a thermoplastic elastomer containing a specific block copolymer, whereby the hot melt adhesive of the present invention exhibits excellent adhesion retention.

  As the styrene-ethylene-butylene-olefin crystal block copolymer (A), a polymer block (A1) having a styrene component of 90% by weight or more and a polybutadiene polymer having a 1,2-vinyl bond content of 30 to 70%. A block copolymer composed of a combined block (A2) and a polybutadiene polymer block (A3) having a 1,2-vinyl bond content of less than 30% is converted into at least 80% or more olefinic non-blocking component in the block copolymer. A hydrogenated block copolymer obtained by hydrogenating a saturated bond and having a number average molecular weight of 40,000 to 700,000 is preferable. The polybutadiene polymer block (A3) becomes a crystalline block segment showing a structure similar to that of low-density polyethylene by hydrogenation. In the present invention, the number average molecular weight of a polymer refers to a value calculated from a GPC pattern and a calibration curve of a sample having an unknown molecular weight by preparing a calibration curve of molecular weight and elution volume from GPC measurement of standard polystyrene with a known molecular weight. In the hydrogenated block copolymer, the presence or absence of crystalline block segments can be analyzed by a differential scanning calorimeter (DSC). After the styrene-ethylene-butylene-olefin crystal block copolymer (A) is heated and melted, it is cooled to −140 ° C. at a temperature lowering rate of 10 ° C./min, and then to 150 ° C. at a temperature rising rate of 20 ° C./min. When the temperature is raised, an endothermic peak is observed at 40 to 110 ° C. when the polymer contains a crystalline block segment.

In the present invention, the 1,2-vinyl bond content refers to a value calculated based on the following formula in the polymer block.
1,2-vinyl bond content (%)
= 100 × (1,2-vinyl bond amount)
/ [(1,2-vinyl bond amount) + (1,4-vinyl bond amount)]

  In the polymer block (A1) of the styrene-ethylene-butylene-olefin crystal block copolymer (A) before hydrogenation, if the content of the styrene component is small, the adhesive strength of the hot melt adhesive may be reduced. Therefore, 90% by weight or more is preferable.

  In the styrene-ethylene-butylene-olefin crystal block copolymer (A) before hydrogenation, the content of 1,2-vinyl bonds in the polybutadiene polymer block (A2) is preferably 30 to 70%. When the content of the 1,2-vinyl bond is small, a polyethylene chain is formed by hydrogenation and the rubber elasticity is lowered, so that the adhesive retention of the hot melt adhesive may be lowered. On the other hand, if the content of the 1,2-vinyl bond is large, the glass transition temperature is increased by hydrogenation and the rubber elasticity is lowered, so that the adhesive retention of the hot melt adhesive may be lowered.

  The content of the polymer block (A2) in the styrene-ethylene-butylene-olefin crystal block copolymer (A) before hydrogenation is preferably 30 to 80% by weight, and more preferably 35 to 70% by weight.

  In the styrene-ethylene-butylene-olefin crystal block copolymer (A) before hydrogenation, the content of 1,2-vinyl bonds in the polybutadiene polymer block (A3) is preferably less than 30%. When the content of the 1,2-vinyl bond is large, a crystalline block segment showing a structure similar to that of low-density polyethylene is not formed even when hydrogenated, and the adhesive retention of the hot melt adhesive may be reduced. is there.

  5-30 weight% is preferable and, as for content of the polymer block (A3) in the styrene-ethylene-butylene-olefin crystal block copolymer (A) before hydrogenation, 15-25 weight% is more preferable.

  As a method for producing the styrene-ethylene-butylene-olefin crystal block copolymer (A), first, 1,3-butadiene is polymerized using an organolithium initiator, and then the 1,2-vinyl bond content is 30 to 30. 1,3-Butadiene is polymerized to 70% to produce block-shaped polybutadiene having different 1,2-vinyl bond contents. Next, a block copolymer before hydrogenation is produced by adding a vinyl aromatic compound containing 90% by weight or more of styrene to polybutadiene for polymerization. And a styrene-ethylene-butylene-olefin crystal block copolymer (A) can be manufactured by hydrogenating the block copolymer before hydrogenation in a well-known manner.

  Examples of the vinyl aromatic compound include styrene, t-butyl styrene, α-methyl styrene, p-methyl styrene, divinyl benzene, 1,1-diphenyl styrene, N, N-diethyl-p-aminoethyl styrene, and vinyl. Examples include pyridine. Of these, styrene and α-methylstyrene are preferable.

  Examples of the organic lithium compound include n-butyllithium, sec-butyllithium, tert-butyllithium, propyllithium, amyllithium, and butyllithium / barium nonylphenoxide / trialkylaluminum / dialkylaminoethanol.

  As the olefin crystal-ethylene butylene-olefin crystal block copolymer (B), a polybutadiene polymer block (C) having a 1,2-vinyl bond content of 20% or less and a polybutadiene block or a vinyl aromatic compound-butadiene copolymer are used. A polymer block comprising a polymer block (D) having a 1,2-vinyl bond content in the butadiene portion of 25 to 95% and a block structure of C- (D-C) n or (C-D) A block copolymer obtained by hydrogenating 90% or more of a butadiene portion of a linear or branched block copolymer represented by m (where n is an integer of 1 or more and m is an integer of 2 or more). Polymers are preferred.

  The polybutadiene polymer block (C) in the block copolymer before hydrogenation becomes a crystalline block segment showing a structure similar to ordinary low-density polyethylene by hydrogenation. In the block copolymer, the presence or absence of the crystalline block segment can be analyzed by a differential scanning calorimeter (DSC). After the olefin crystal-ethylenebutylene-olefin crystal block copolymer (B) is heated and melted, it is cooled to -140 ° C. at a temperature decrease rate of 10 ° C./min, and then to 150 ° C. at a temperature increase rate of 20 ° C./min. When the temperature is raised, an endothermic peak is observed at 40 to 110 ° C. when the polymer contains a crystalline block segment.

  The content of 1,2-vinyl bonds in the polybutadiene polymer block (C) in the block copolymer before hydrogenation is preferably 20% or less. When the content of the 1,2-vinyl bond is large, a crystalline block segment showing a structure similar to that of low-density polyethylene is not formed even when hydrogenated, and the adhesive retention of the hot melt adhesive may be reduced. is there.

  The polymer block (D) in the block copolymer before hydrogenation is similar to the rubbery ethylene-butene copolymer or rubbery vinyl aromatic compound-ethylene-butene copolymer by hydrogenation. It becomes a polymer block showing the structure.

  Examples of the vinyl aromatic compound include styrene, t-butyl styrene, α-methyl styrene, p-methyl styrene, divinyl benzene, 1,1-diphenyl styrene, N, N-diethyl-p-aminoethyl styrene, and vinyl. Examples include pyridine. Of these, styrene and α-methylstyrene are preferable.

  The content of 1,2-vinyl bonds in the butadiene portion in the polymer block (D) of the block copolymer before hydrogenation is preferably 25 to 95%, more preferably 25 to 75%, and more preferably 25 to 55%. Is particularly preferred. Even if the content of the 1,2-vinyl bond is small or large, it shows a crystal structure derived from polyethylene chain or polybutene-1 chain after hydrogenation, and rubber elasticity is lowered. Holding power may be reduced.

  The content of the polybutadiene polymer block (C) in the block copolymer before hydrogenation is preferably 5 to 90% by weight, and more preferably 10 to 85% by weight. If the content of the polybutadiene polymer block (C) is small, the crystalline polymer block may be insufficient, and the adhesion retention of the hot melt adhesive may be lowered. Moreover, when there is much content of a polybutadiene polymer block (C), the adhesive retainability of a hot-melt-adhesive agent may fall.

  10-95 weight% is preferable and, as for content of the polymer block (D) in the block copolymer before hydrogenation, 15-90 weight% is more preferable. When there is little content of the said polymer block (D), the adhesive retainability of a hot-melt-adhesive agent may fall. Moreover, when there is much content of the said polymer block (D), a crystalline polymer block may run short and the adhesiveness retention of a hot-melt-adhesive agent may fall.

  As a method for producing the olefin crystal-ethylene butylene-olefin crystal block copolymer (B), 1,3-butadiene is polymerized using an organolithium initiator so that the 1,2-vinyl bond content is 20% or less. After the polymerization, 1,3-butadiene or a vinyl aromatic compound and 1,3-butadiene are polymerized so that the 1,2-vinyl bond content of the butadiene portion is 25 to 95%. The block copolymer is produced. An olefin crystal-ethylene butylene-olefin crystal block copolymer (B) can be produced by hydrogenating the butadiene portion of this block copolymer so as to be 90% or more in a known manner.

  The content of the thermoplastic elastomer in the hot melt adhesive is preferably 1 to 30 parts by weight and more preferably 15 to 25 parts by weight with respect to 100 parts by weight of the ethylene-octene copolymer. When the content of the thermoplastic elastomer is small, the adhesive holding power of the hot melt adhesive may be reduced. Moreover, when there is much content of a thermoplastic elastomer, the sprayability of a hot-melt-adhesive may fall.

  The thermoplastic elastomer contains at least one of a styrene-ethylene-butylene-olefin crystal block copolymer (A) and an olefin crystal-ethylenebutylene-olefin crystal block copolymer (B).

  When both the styrene-ethylene-butylene-olefin crystal block copolymer (A) and the olefin crystal-ethylenebutylene-olefin crystal block copolymer (B) are contained as the thermoplastic elastomer, The content of the styrene-ethylene-butylene-olefin crystal block copolymer (A) is preferably 20 to 80% by weight. When there is little content of a block copolymer (A), the adhesive retention of a hot-melt-adhesive agent may fall. Moreover, when there is much content of a block copolymer (A), the sprayability of a hot-melt-adhesive agent may fall. On the other hand, the content of the olefin crystal-ethylene butylene-olefin crystal block copolymer (B) in the thermoplastic elastomer is preferably 20 to 80% by weight. When there is little content of a block copolymer (B), the sprayability of a hot-melt-adhesive may fall. Moreover, when there is much content of a block copolymer (B), the adhesive retention of a hot-melt-adhesive agent may fall.

  Examples of the styrene-ethylene-butylene-olefin crystal block copolymer (A) include trade name “DYNARON 4600P” manufactured by JSR Corporation. Examples of the olefin crystal-ethylene butylene-olefin crystal block copolymer (B) include trade name “DYNARON 6200P” manufactured by JSR Corporation.

  The hot melt adhesive of the present invention contains a tackifying resin. The tackifying resin is not particularly limited. For example, natural rosin, modified rosin, hydrogenated rosin, natural rosin glycerol ester, modified rosin glycerol ester, natural rosin pentaerythritol ester, modified rosin pentaerythritol ester, water Pentaerythritol ester of rosin, natural terpene copolymer, three-dimensional polymer of natural terpene, hydrogenated derivative of natural terpene copolymer, terpene resin, hydrogenated terpene resin, hydrogenated derivative of phenolic modified terpene resin; C5 petroleum resin , C9 petroleum resin, C5C9 petroleum resin, dicyclopentadiene petroleum resin and other petroleum resins; petroleum resin hydrogenated products. In addition, tackifying resin may be used independently or 2 or more types may be used together. In the hydrogenated product of petroleum resin, all of the unsaturated bonds present in the petroleum resin may be hydrogenated (hydrogenation rate: 100%) or a part of the unsaturated bonds may be hydrogenated. .

  The tackifying resin is preferably a hydrogenated resin such as a hydrogenated petroleum resin, a hydrogenated terpene resin, or a hydrogenated rosin, more preferably a hydrogenated petroleum resin, and all of the unsaturated bonds are hydrogenated. Petroleum resin is particularly preferred. These tackifying resins can reduce the hot melt adhesive from seeping out from the moisture permeable film, and can improve the sprayability and thermal stability of the hot melt adhesive.

  As the tackifying resin, from the viewpoint of improving the adhesion retention and adhesion of the hot-melt adhesive, a petroleum resin hydrogenated product and a non-hydrogenated petroleum resin may be used in combination. In such a case, the content of the hydrogenated product of the petroleum resin in the tackifying resin is preferably 40% by weight or more, more preferably 40 to 90% by weight, and more preferably 50 to 70% by weight with respect to the total amount of the tackifying resin. % Is more preferable. The content of the non-hydrogenated petroleum resin in the tackifying resin is preferably 60% by weight or less, more preferably 10 to 60% by weight, and more preferably 30 to 50% by weight with respect to the total amount of the tackifying resin. .

  The ring-and-ball softening point temperature of the adhesion-imparting resin is preferably 85 ° C. or higher and more preferably 90 ° C. or higher because a hot melt adhesive composition having excellent cohesive strength, thermal stability and creep suitability can be obtained. In addition, the ring and ball softening point temperature of the tackifying resin is preferably 125 ° C. or lower, more preferably 120 ° C. or lower, because the hot melt adhesive composition can be made flexible and can be prevented from becoming brittle. . The ring and ball softening point temperature of the tackifier resin is a value measured in accordance with JIS K 2207.

  In addition, as a commercial item of tackifying resin, for example, trade name “Escollet 5600” manufactured by Tonex Co., Ltd., trade name “Marca Clear H” manufactured by Maruzen Petrochemical Co., Ltd., and product name “Clearon K100” manufactured by Yasuhara Chemical Co., Ltd. Product name “Arcon P100” manufactured by Arakawa Chemical Co., Ltd. Product name “Arcon M100” manufactured by Arakawa Chemical Co., Ltd. Product name “Imabe S100” manufactured by Idemitsu Petrochemical Co., Ltd. Product name “Clearon K4090” manufactured by Yasuhara Chemical Co., Ltd., Tonex The product name “ECR231C” manufactured by the company, the product name “Rigalite R7100” manufactured by Eastman Chemical Company, the product name “Rigalite C6100” manufactured by Eastman Chemical Company, and the like can be given.

  60-150 weight part is preferable with respect to 100 weight part of ethylene-octene copolymers, and, as for content of tackifying resin in a hot-melt-adhesive, 85-130 weight part is more preferable. When the content of the tackifying resin is small, the adhesive strength of the hot melt adhesive may be reduced. Moreover, when there is much content of tackifying resin, a hot-melt-adhesive agent will become hard and the texture of a to-be-adhered body may fall.

  The hot melt adhesive preferably contains a plasticizer. By using a plasticizer, it is difficult for the hot melt adhesive to exude from an adherend such as a moisture permeable film, and at the time of melting, an appropriate viscosity is imparted to the hot melt adhesive to improve the sprayability of the hot melt adhesive. Can be improved.

  The plasticizer is not particularly limited, and examples thereof include paraffinic, naphthenic, or aromatic process oils; liquid polybutene, liquid polybutadiene, liquid polyisoprene, and other resins that are liquid at room temperature (weight average molecular weight Mw: 300 to 10000); hydrogenated products of these liquid resins; natural or synthetic waxes of paraffinic wax, microcrystalline wax, low molecular weight polyolefin wax (weight average molecular weight Mw: 1000 to 30000); a mixture of two or more of these Can be mentioned. In addition, a plasticizer may be used independently or 2 or more types may be used together. Of these, paraffin wax is preferred. By using paraffin wax, the thermal stability of the hot melt adhesive can be improved.

  Commercially available plasticizers include, for example, the product name “LP350” manufactured by Kukdon Oil & Chem, the product name “Diana Fresia S32” manufactured by Idemitsu Kosan Co., Ltd., and the product name “PS-32” manufactured by Idemitsu Kosan Co., Ltd. Product name “Diana Process Oil PW-90” manufactured by BP Chemicals, product name “Emerper M1930” manufactured by BP Chemicals, product name “Kaydol” manufactured by Crompton, product name “White Rex 335” manufactured by TonenGeneral Sekiyu KK, Petro China The product name “KN4010” manufactured by the company and the product name “150F” manufactured by Nippon Seiwa Co., Ltd. can be exemplified.

  The content of the plasticizer in the hot melt adhesive is preferably 50 to 100 parts by weight and more preferably 55 to 80 parts by weight with respect to 100 parts by weight of the ethylene-octene copolymer. When the content of the plasticizer is small, the sprayability of the hot melt adhesive may be lowered. Moreover, when there is much content of a plasticizer, the adhesiveness retention of a hot-melt-adhesive agent may fall.

  The hot melt adhesive preferably contains an antioxidant. The antioxidant is not particularly limited, and examples thereof include 2,6-di-t-butyl-4-methylphenol and n-octadecyl-3- (4′-hydroxy-3 ′, 5′-di-t-). Butylphenyl) propionate, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6-tert-butylphenol), 2,4-bis (octylthiomethyl) ) -O-cresol, 2-t-butyl-6- (3-t-butyl-2-hydroxy-5-methylbenzyl) -4-methylphenyl acrylate, 2,4-di-t-amyl-6 [1- (3,5-di-t-amyl-2-hydroxyphenyl) ethyl] phenyl acrylate, 2- [1- (2-hydroxy-3,5-di-tert-pentylphenyl)] acrylate Hindered phenolic antioxidants such as tetrakis [methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane; dilauryl thiodipropionate, lauryl stearyl thiodipropionate, Sulfur-based antioxidants such as pentaerythritol tetrakis (3-laurylthiopropionate); phosphorus-based antioxidants such as tris (nonylphenyl) phosphite and tris (2,4-di-t-butylphenyl) phosphite Etc. Antioxidants may be used alone or in combination of two or more.

  Examples of commercially available antioxidants include trade names “Irganox 1010”, “Irganox 1520”, “Irganox HP2225FF”, “Irgafos 168” manufactured by BASF Japan, and “Irganos 168”. Examples thereof include “Sumilyzer TP-D”, “Sumilyzer-GM”, and “Sumilyzer-TPS”.

  The content of the antioxidant in the hot melt adhesive is preferably 0.7 to 2.5 parts by weight with respect to 100 parts by weight of the ethylene-octene copolymer. When the content of the antioxidant is small, it may not be possible to prevent the molecular weight from being lowered, gelled, colored, or odor generated by the heat of the hot melt adhesive. Moreover, when there is much content of antioxidant, antioxidant may bleed out on the surface of a hot-melt-adhesive, and the adhesive force of a hot-melt-adhesive may fall.

  In addition, the hot melt adhesive of the present invention may contain additives such as fillers, light stabilizers, ultraviolet absorbers and the like as long as the physical properties are not impaired.

  The hot melt adhesive of the present invention is first heated to 120 to 170 ° C., more preferably 130 to 160 ° C., to obtain a molten state having an appropriate melt viscosity. Next, the molten hot melt adhesive is applied to the adherend by spraying or the like. And after adhering adherends through a hot melt adhesive, the hot melt adhesive is cooled. As a result, the adherends can be bonded and integrated. As the adherend, a substrate, a moisture permeable film, or the like is used.

  As a method for applying the hot melt adhesive to the adherend, a non-contact coating method is preferable. The non-contact coating method means a coating method in which a spray (spouter) is not brought into contact with an adherend when a hot melt adhesive is applied. For example, spiral coating that can be applied spirally, omega coating or control seam coating that can be applied in a wavy shape, slot spray coating or curtain spray coating that can be applied in the form of a surface, dot coating that can be applied in the form of dots, etc. Can be mentioned.

  Hot melt adhesives are preferably used in the manufacture of disposable products. Although it does not specifically limit as a disposable product, For example, what is called hygiene materials, such as a paper diaper, a sanitary napkin, a pet sheet, a hospital gown, and a lab coat, etc. are mentioned.

  Since the hot melt adhesive of the present invention has the configuration as described above, it has an excellent adhesive force, does not ooze from the adherend, exhibits an excellent adhesive holding force, and is suitable for spraying. In addition to being excellent, it has excellent thermal stability, hardly decomposes or deteriorates even when heated in the tank, and hardly causes thermal deterioration even when it is used continuously for a long time.

(Examples 1-13, Comparative Examples 1-6)
Ethylene-octene copolymer 1 (trade name “Affinity GA1875” manufactured by DOW Chemical, MFR: 1250 g / 10 min), ethylene-octene copolymer 2 (trade name “ENGAGE 8407” manufactured by DOW Chemical, MFR: 30 g / 10 minutes), ethylene-octene copolymer 3 (trade name “INFUSE 9807” manufactured by DOW Chemical, MFR: 15 g / 10 minutes), propylene polymer (trade name “RT 2115” manufactured by REXtac LLC), propylene-butene Copolymer ("RT 2715" manufactured by REXtac LLC), styrene-ethylene-butylene-olefin crystal block copolymer (SEBC, product name "DYNARON 4600P" manufactured by JSR), olefin crystal-ethylenebutylene-olefin bond Block copolymer (CEBC, trade name “DYNARON 6200P” manufactured by JSR), styrene-ethylene-butadiene-styrene elastomer 1 (SEBS1, trade name “DYNARON 8600P” manufactured by JSR), styrene-ethylene-butadiene-styrene elastomer 2 (SEBS2, trade name “G-1726” manufactured by Kraton Polymer Co., Ltd.), hydrogenated product of petroleum resin (trade name “Arcon P-100” manufactured by Arakawa Chemical Co., Ltd.), ring and ball softening point temperature: 100 ° C., hydrogenation rate: 100 %), Hydrogenated petroleum resin (trade name “Arcon M-100” manufactured by Arakawa Chemical Co., Ltd., ring and ball softening point temperature: 100 ° C., hydrogenation rate: 70%), petroleum resin (non-hydrogenated) (Exon Mobile) “Escollet 1310”, ring and ball softening point temperature: 93 ° C., hydrogenation rate: 0%), naphthenic pro Suoil (trade name “KN4010” manufactured by Petro China), paraffin wax (trade name “150F” manufactured by Nippon Seiwa Co., Ltd.) and hindered phenol antioxidant (trade name “Irganox 1010” manufactured by BASF Japan) The hot melt adhesive was manufactured by melting and kneading at 170 ° C. in the amounts shown in Tables 1 and 2, respectively.

  The thermal stability (compatibility, generation of foreign matter), sprayability, adhesion holding power, adhesion strength and oozing property of the obtained hot melt adhesive were measured in the following manner, and the results are shown in Tables 1 and 2. .

[Thermal stability (compatibility)]
20 g of hot melt adhesive was put in a glass bottle, put in a hot air dryer at 180 ° C. without a lid, and after 72 hours, the presence or absence of separation of the hot melt adhesive in a high temperature state was visually observed. The case where it was transparent without separation was designated as “◎”, the case where it was not separated but became opaque was designated as “◯”, and the case where it was separated was designated as “X”.

[Thermal stability (foreign matter generation)]
20 g of hot melt adhesive was put in a glass bottle, put in a 180 ° C. hot air dryer without a lid, and after 72 hours, whether or not carbonization and foreign matter were generated in the hot melt adhesive in a high temperature state was visually observed. . The case where the occurrence of carbonization and foreign matter was not confirmed was indicated as “◯”, and the case where carbonization or foreign matter occurred was indicated as “x”.

[Sprayability]
The hot melt adhesive was spirally applied to the center of a polyethylene terephthalate film (thickness: 50 μm) at a coating temperature of 160 ° C., a coating amount of 5 g / m ² , and a coating width of 17 mm using an ejector. Another polyethylene terephthalate film was superposed on the polyethylene terephthalate film via a hot melt adhesive, pressed, and then the hot melt adhesive was cooled to room temperature. Thus, two polyethylene terephthalate films were bonded and integrated through a hot melt adhesive to produce a laminated sheet. The hot melt adhesive of the laminated sheet was visually observed through a polyethylene terephthalate film. The case where the spiral pattern of the hot melt adhesive was retained was designated as “◎”. Although the spiral pattern was retained, a case where the hot melt adhesive was scattered around the spiral pattern within a range not causing a problem in the use of the product was indicated as “◯”. The case where it was necessary to increase the coating pressure of the ejector in order to maintain the spiral pattern was indicated as “Δ”. The case where there was a problem in the use of the product was designated as “x”.

[Adhesive retention strength]
A laminated sheet was produced in the same manner as in the measurement of sprayability. The laminated sheet was cut into a flat rectangular shape having a width of 2.5 cm and a length of 9 cm to prepare a test piece. The test piece was disposed in a state where the surface of the polyethylene terephthalate film faced the vertical direction. A 500 g weight was attached to the surface of the polyethylene terephthalate film of the test piece. The weight was attached to the center in the width direction at the lower end of the test piece. In this state, the test piece was left under the condition of 40 ° C., and the time from when the test piece was left until the 500 g weight dropped was measured. The case where it took more than 6 minutes to fall was designated as “◎”. A case where the time until dropping was 4 minutes or more and less than 6 minutes was defined as “◯”. The case where the time until dropping was 2 minutes or more and less than 4 minutes was defined as “Δ”. And when it was less than 2 minutes until it dropped, it was set as "x".

[Adhesive strength]
A hot melt adhesive was spirally coated on a spunbonded nonwoven fabric at a coating temperature of 160 ° C., a coating amount of 5 g / m ² , and a coating width of 17 mm. And the hot melt adhesive was cooled to room temperature. As a result, the spunbonded nonwoven fabric and the moisture-permeable polyethylene film were bonded and integrated with each other via a hot melt adhesive to prepare a test piece. The test piece was cut into a strip shape having a width of 25 mm in the direction parallel to the direction of the spiral pattern and the spiral pattern being in the middle, and the 180 ° peel strength (g / 17 mm) was measured under a peel rate of 300 mm / min. . The case where the peel strength was 150 g / 17 mm or more was designated as “◎”. A case where the peel strength was 130 g / 17 mm or more and less than 150 g / 17 mm was defined as “◯”. A case where the peel strength was 100 g / 17 mm or more and less than 130 g / 17 mm was defined as “Δ”. And the case where peeling strength was less than 100g / 17mm was made into "x".

[Bleedability]
A test piece was prepared in the same manner as the measurement of adhesive strength, and this test piece was left in a hot air dryer at 60 ° C. for 24 hours, and then the test piece was left at 20 ° C. for 10 minutes. . The surface of the moisture-permeable polyethylene film of the test piece was visually observed. A case where the spiral pattern did not ooze out on the surface of the moisture-permeable polyethylene film and the spiral pattern could not be discriminated was designated as “◎”. A case where the spiral pattern slightly exudes on the surface of the moisture-permeable polyethylene film but the spiral pattern could not be discriminated was indicated as “◯”. And when the spiral pattern oozes out on the surface of a moisture-permeable polyethylene film and the spiral pattern was able to be discriminated, it was set as "x".

Claims (2)

100 parts by weight of an ethylene-octene copolymer, 1-30 parts by weight of a thermoplastic elastomer containing a styrene-ethylene-butylene-olefin crystal block copolymer and / or an olefin crystal-ethylenebutylene-olefin crystal block copolymer, A hot-melt adhesive comprising 60 to 150 parts by weight of a tackifying resin.   A disposable product comprising the hot melt adhesive according to claim 1.