JP2016204541A - Moisture-curable hot melt adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a moisture curable hot melt adhesive excellent in holding powder of a sheet at high temperature (50°C) while having ordinal condition adhesive strength and heat creep resistance at high levels.SOLUTION: The moisture curable hot melt adhesive is a reaction product of a polyisocyanate compound and a raw material composition containing crystalline polyester polyol of 20 to 30 mass%, polyether polyol of 35 to 40 mass%, an acrylic copolymer having glass transition temperature of 50 to 90°C of 15 to 25 mass% and thermoplastic polycaprolactone of 3 to 7 mass% and contains an urethane polymer containing an isocyanate group in a terminal.SELECTED DRAWING: None

Description

  The present invention relates to a moisture curable hot melt adhesive.

  2. Description of the Related Art Conventionally, design properties are imparted by adhering a decorative sheet with makeup such as coloring to the surface of a base material such as furniture, exterior material, and interior material using an adhesive.

  As an adhesive used for adhesion between a base material and a decorative sheet, an adhesive containing an organic solvent and a moisture curable hot melt adhesive are known. In particular, moisture-curing hot melt adhesives are often used because they do not contain volatile organic compounds (VOC) that cause sick house syndrome and are measures against occupational hygiene and environmental pollution.

  As the moisture curable hot melt adhesive, for example, a hot melt adhesive mainly composed of a urethane prepolymer having an isocyanate group at the molecular end is used (for example, Patent Document 1). Such a moisture-curing hot melt adhesive is applied to a substrate in a heated and melted state, and then cooled and solidified to express initial adhesive strength. After that, by leaving the substrate coated with the moisture-curable hot melt adhesive for a certain period of time, the isocyanate group reacts with the moisture contained in the atmosphere or the substrate, so that the urethane prepolymer has a crosslinked structure. The moisture curable hot melt adhesive is cured and the adhesive strength is further improved.

JP 2001-262113 A

  In adhering the decorative sheet to the surface of the base material using a moisture curable hot melt adhesive, the moisture curable hot melt adhesive exhibits initial adhesive strength by cooling and solidifying, and fixes the decorative sheet. However, if the atmospheric temperature is high, it takes time to solidify, and the development of the initial adhesive strength is delayed. For example, in summer, the substrate surface temperature may be 50 ° C. Therefore, in the summer, the sheet is likely to float or peel off immediately after being laminated.

  Further, the melt viscosity of moisture-curable hot melt adhesives currently used for bonding decorative sheets is mainly 40000 mP · s or less at 120 ° C. If the melt viscosity of the moisture curable hot melt adhesive is 40000 mP · s or less at 120 ° C., the same workability as before can be expected. Considering workability, the melt viscosity of the moisture-curable hot melt adhesive is preferably 40000 mP · s or less at 120 ° C.

  Accordingly, an object of the present invention is to maintain a sheet holding power at a high temperature (50 ° C.) while maintaining a high level of normal adhesive strength and heat-resistant creep properties, which are basic properties required for a moisture-curable hot melt adhesive. It is to provide a moisture curable hot melt adhesive having excellent initial adhesive strength.

  The moisture-curable hot melt adhesive of the present invention is a crystalline polyester polyol of 20 to 30% by mass, which is a condensation polymer of a linear polycarboxylic acid having 12 carbon atoms and a linear polyol having 6 carbon atoms. A raw material composition and a polyisocyanate containing 35 to 40% by weight of a polyether polyol, 15 to 25% by weight of an acrylic copolymer having a glass transition temperature of 50 to 90 ° C., and 3 to 7% by weight of a thermoplastic polycaprolactone A urethane prepolymer which is a reaction product with a compound and which contains an isocyanate group at a terminal, and in the raw material composition, the crystalline polyester polyol, the polyether polyol, and the acrylic copolymer The total amount of the thermoplastic polycaprolactone and the polyisocyanate compound is 100% by mass. And wherein the door.

  The moisture curable hot melt adhesive has a melt viscosity at 120 ° C. of 40000 mPa · s or less.

  The moisture curable hot melt adhesive of the present invention is a basic performance required for a moisture curable hot melt adhesive, which is a high level of normal adhesive strength and heat-resistant creep resistance, at a high temperature (50 ° C.). Excellent sheet holding power (initial adhesive strength).

  The moisture-curable hot melt adhesive of the present invention is a crystalline polyester polyol, polyether polyol, which is a condensation polymer of a linear polycarboxylic acid having 12 carbon atoms and a linear polyol having 6 carbon atoms, A urethane prepolymer which is a reaction product of an acrylic copolymer having a glass transition temperature of 50 to 90 ° C. and a raw material composition containing a thermoplastic polycaprolactone and a polyisocyanate compound, and containing an isocyanate group at the terminal. Contains polymer.

(Crystalline polyester polyol)
The raw material composition contains a crystalline polyester polyol. The crystalline polyester polyol is a condensation polymer of a linear polycarboxylic acid having 12 carbon atoms and a linear polyol having 6 carbon atoms.

  In the moisture curable hot melt adhesive, a crystalline polyester polyol having crystallinity is used as the polyester polyol. By using the crystalline polyester polyol, the initial adhesive strength of the moisture curable hot melt adhesive is expressed.

  Whether or not the polyester polyol is crystalline is determined based on the following criteria. In the present invention, the crystalline polyester polyol means that the endothermic amount of the melting curve measured at a heating rate of 10 ° C./min in the differential scanning calorimetry (DSC) measurement specified in JIS K7121 is 3 cal / g (12 558 J / g) or higher. The non-crystalline polyester polyol has an endothermic amount of 3 cal / g (12.558 J / g) measured by a differential scanning calorimetry (DSC) specified in JIS K7121 at a heating rate of 10 ° C./min. g) means a polyester polyol that is less than

  Examples of the linear polycarboxylic acid having 12 carbon atoms include dodecanedioic acid, and linear dicarboxylic acids having carboxy groups (—COOH) at both ends and having 12 carbon atoms are preferable. Diacid is preferred.

  Examples of the linear polyol having 6 carbon atoms include hexanediol, and a linear polyol having hydroxyl groups (—OH) at both ends and having 6 carbon atoms is preferable. 1,6-hexanediol Is more preferable.

  As the crystalline polyester polyol, since the initial adhesive strength of the moisture curable hot melt adhesive is excellent, a linear dicarboxylic acid having a carboxy group at both ends and having 12 carbon atoms, and a hydroxyl group at both ends And is a condensation polymer of a straight-chain polyol having 6 carbon atoms, and is preferably a condensation polymer of dodecanedioic acid and 1,6-hexanediol.

  The number average molecular weight of the crystalline polyester polyol is 400 to 10000, preferably 1000 to 5000, and more preferably 2000 to 4000. When the number average molecular weight of the crystalline polyester polyol is within the above range, the molecular chain length between cross-linking points in the urethane prepolymer becomes an appropriate length, and the moisture-curable hot melt adhesive has excellent initial adhesive strength.

  The number average molecular weight of the crystalline polyester polyol, polyether polyol, acrylic copolymer, and thermoplastic polycaprolactone is a value measured in the following manner. The number average molecular weight can be measured using a gel permeation chromatograph (GPC) method. For example, a sample solution is prepared by dissolving polyether polyol in tetrahydrofuran (THF) so as to have a concentration of 1.0% by mass, and a standard solution is prepared by GPC method using the sample solution and measurement conditions described below. The measurement can be performed using a refractive index detector based on polystyrene.

  As a measuring device, for example, a system (all manufactured by Shimadzu Corp.) comprising LC-9A for liquid feeding device, RID-6A for refractive index detector, CTO-6A for column oven, and C-R4A for data analysis device. Can be used. As the GPC column, for example, three GPC-805 (exclusion limit of 4 million) and one GPC-804 (exclusion limit of 400,000) (both manufactured by Shimadzu Corporation) can be connected in this order and used. The measurement conditions are a sample injection volume of 25 μL (liter), an eluent tetrahydrofuran (THF), a liquid feed volume of 1.0 mL / min, and a column temperature of 45 ° C.

  The content of the crystalline polyester polyol in the raw material composition is 20 to 20% when the total amount of the crystalline polyester polyol, polyether polyol, acrylic copolymer, thermoplastic polycaprolactone, and polyisocyanate compound is 100% by mass. 30 mass%, and preferably 23-27 mass%. When the content of the crystalline polyester polyol is 20% by mass or more, the moisture curable hot melt adhesive is excellent in initial adhesive strength. When the content of the crystalline polyester polyol is 30% by mass or less, the open time of the moisture curable hot melt adhesive becomes long and high adhesive strength is maintained.

(Polyether polyol)
The raw material composition contains a polyether polyol. The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyoxyethylene polyoxypropylene glycol, and an alkylene oxide adduct of bisphenol A represented by the structural formula of Chemical Formula 1. Can be mentioned. As the polyether polyol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol, and an alkylene oxide adduct of bisphenol A are preferable, and polypropylene glycol is more preferable. Among the alkylene oxide adducts of bisphenol A, an adduct formed by adding ethylene oxide and / or propylene oxide to bisphenol A is more preferable. In polyoxyethylene polyoxypropylene glycol, the arrangement of polyoxyethylene units and polyoxypropylene units may be random or block. The alkylene oxide adduct of bisphenol A can be obtained, for example, by subjecting an active hydrogen of bisphenol A to an alkylene oxide addition reaction. Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide, and isobutylene oxide. When two or more types of alkylene oxide are added to bisphenol A, the arrangement of each alkylene oxide unit may be random or block.

  It is preferable that the polyether polyol contained in the raw material composition does not contain a hydrolyzable silyl group. The hydrolyzable silyl group is a group formed by bonding 1 to 3 hydrolyzable groups to a silicon atom.

  The hydrolyzable group of the hydrolyzable silyl group is not particularly limited, and examples thereof include a hydrogen atom, an alkoxy group, an acyloxy group, a ketoximate group, an aminooxy group, a mercapto group, and an alkenyloxy group.

式中、ｎ及びｍは、正の整数である。

In the formula, n and m are positive integers.

  The number average molecular weight of the polyether polyol is 400 to 10000, preferably 1000 to 5000, and more preferably 2000 to 4000. When the number average molecular weight of the polyether polyol is within the above range, the molecular chain length between crosslinking points in the urethane prepolymer becomes an appropriate length, and the moisture-curable hot melt adhesive has excellent initial adhesive strength.

  The content of the polyether polyol in the raw material composition is 35 to 40 masses when the total amount of the crystalline polyester polyol, polyether polyol, acrylic copolymer, thermoplastic polycaprolactone and polyisocyanate compound is 100 mass%. %, And preferably 36 to 38% by mass. When the content of the polyether polyol is 35% by mass or more, the melt viscosity of the moisture-curable hot melt adhesive is lowered, and workability and adhesiveness are improved. When the content of the moisture curable hot melt adhesive is 40% by mass or less, the moisture curable hot melt adhesive has excellent initial adhesive strength.

  The raw material composition may contain a polyol other than the polyester polyol and the polyether polyol as long as the physical properties of the moisture-curable hot melt adhesive are not impaired. Examples of such polyols include polyester polyols other than the above polyester polyols, polyether polyols other than the above polyether polyols, polyalkylene polyols, and polycarbonates.

(Acrylic copolymer)
The acrylic copolymer is a copolymer of (meth) acrylic acid and an acrylic monomer. In the present invention, (meth) acrylic acid means acrylic acid or methacrylic acid. An acrylic copolymer may be used independently or 2 or more types may be used together.

  The acrylic monomer is not particularly limited as long as it can be copolymerized with (meth) acrylic acid. For example, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl ( (Meth) acrylate, isobutyl (meth) acrylate, sec-butyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n- Examples thereof include alkyl (meth) acrylates such as nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, and lauryl (meth) methacrylate. In addition, an acrylic monomer may be used independently or 2 or more types may be used together. In the present invention, (meth) acrylate means acrylate or methacrylate.

  Acrylic copolymers are, for example, trade names “Dynacol AC1630”, “Dynacol AC1920”, “Dynacol AC4830”, and “Dynacol AC1750” from Evonik Japan, and trade names “Dynar BR” from Mitsubishi Rayon. 113 "and" Dianar BR-122 ".

  The number average molecular weight of the acrylic copolymer is preferably 80000 or more, and more preferably 120,000 or more. When the acrylic copolymer has a number average molecular weight of 80,000 or more, the acrylic copolymer has a large molecular weight and thus has a large intermolecular cohesive force, and the moisture-curable hot melt adhesive has excellent initial adhesive strength. The number average molecular weight of the acrylic copolymer is preferably 300000 or less, and more preferably 250,000 or less. When the number average molecular weight of the acrylic copolymer is 300000 or less, a significant increase in viscosity of the moisture curable adhesive is suppressed, and workability of the moisture curable adhesive is improved.

  The glass transition temperature of the acrylic copolymer is 50 to 90 ° C, preferably 50 to 80 ° C. When the glass transition temperature of the acrylic copolymer is within the above range, the time from melting to solidification of the moisture curable hot melt adhesive is appropriate, and the moisture curable hot melt adhesive has excellent initial adhesive strength. Have.

  The glass transition temperature of the acrylic copolymer is measured by DSC in accordance with JIS K7121, heated from room temperature to 120 ° C. at a heating rate of 10 ° C./min, and then from 120 ° C. at a cooling rate of 10 ° C./min. Cool to 0 ° C., and then set the temperature at the midpoint of the step in the DSC curve measured when heated from 0 ° C. to 120 ° C. at a heating rate of 10 ° C./min.

  The content of the acrylic copolymer in the raw material composition is 15 to 15% when the total amount of the crystalline polyester polyol, the polyether polyol, the acrylic copolymer, the thermoplastic polycaprolactone and the polyisocyanate compound is 100% by mass. It is 25 mass%, and 17-22 mass% is preferable. When the content of the acrylic copolymer is 15% by mass or more, the moisture curable hot melt adhesive has excellent initial adhesive strength. When the content of the acrylic copolymer is 25% by mass or less, the melt viscosity of the moisture-curing hot melt adhesive is lowered, and workability and normal adhesive strength are improved.

(Thermoplastic polycaprolactone)
The raw material composition contains thermoplastic polycaprolactone. Thermoplastic polycaprolactone is a polymer produced by ring-opening polymerization of ε-caprolactone.

  The thermoplastic polycaprolactone may be used alone or in combination of two or more. Thermoplastic caprolactone is commercially available from, for example, Perstorp under the trade names “Capa6400” and “Capa6500”. The number average molecular weight of the thermoplastic polycaprolactone is preferably 10,000 to 80,000, and more preferably 30,000 to 80,000. When the number average molecular weight of the thermoplastic polycaprolactone is within the above range, the thermoplastic polycaprolactone has a large molecular weight and therefore has a large intermolecular cohesive force, and the moisture-curable hot melt adhesive has an excellent initial adhesive strength.

  The content of the thermoplastic polycaprolactone in the raw material composition is 3 to 7 when the total amount of the crystalline polyester polyol, polyether polyol, acrylic copolymer, thermoplastic polycaprolactone and polyisocyanate compound is 100% by mass. % By mass, preferably 4-6% by mass. When the content of the thermoplastic polycaprolactone is 3% by mass or more, the moisture-curable hot melt adhesive has excellent initial adhesive strength. When the content of the thermoplastic polycaprolactone is 7% by mass or less, the open time of the moisture curable hot melt adhesive is increased, and the normal adhesive strength is improved.

(Polyisocyanate compound)
A polyisocyanate compound refers to a compound having two or more isocyanate groups in one molecule.

  Examples of the polyisocyanate compound include 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4-diphenylmethane diisocyanate (2,4-MDI), 2,2'-diphenylmethane diisocyanate (2,2 ' -MDI), carbodiimide modified diphenylmethane diisocyanate, polymethylene polyphenyl polyisocyanate, carbodiimidized diphenylmethane polyisocyanate, tolylene diisocyanate (TDI, 2,4, 2,6, or mixtures thereof), xylylene diisocyanate (XDI) 1,5-naphthalene diisocyanate (NDI), tetramethylxylene diisocyanate, phenylene diisocyanate, hexamethylene diisocyanate (HDI), dimer acid diisocyanate , Norbornene diisocyanate, lysine diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, isophorone diisocyanate (IPDI), hydrogenated diphenylmethane diisocyanate (hydrogenated MDI), hydrogenated xylylene diisocyanate (hydrogenated XDI), cyclohexane diisocyanate, dicyclohexyl Examples include methane diisocyanate and isophorone diisocyanate. A polyisocyanate compound may be used independently or 2 or more types may be used together.

  As the polyisocyanate compound, 4,4'-diphenylmethane diisocyanate, 2,4-diphenylmethane diisocyanate, 2,2'-diphenylmethane diisocyanate, and carbodiimide-modified diphenylmethane diisocyanate are preferable, and 4,4'-diphenylmethane diisocyanate is more preferable.

(Urethane prepolymer)
The moisture curable hot melt adhesive contains a urethane prepolymer that is a reaction product of a raw material composition and a polyisocyanate compound and contains an isocyanate group at the terminal.

  Specifically, the urethane prepolymer is obtained by reacting a raw material composition containing crystalline polyester polyol, polyether polyol, acrylic copolymer and thermoplastic polycaprolactone with a polyisocyanate compound.

  In the entire raw material composition and the polyisocyanate compound, the ratio of the total number of moles of isocyanate groups (—NCO) to the total number of moles of hydroxyl groups (—OH) (total number of moles of isocyanate groups / total number of moles of hydroxyl groups) is 1. 5 to 3 is preferable, and 2 to 2.5 is more preferable. When the ratio of the total number of moles of isocyanate groups (—NCO) and the total number of moles of hydroxyl groups (—OH) (total number of moles of isocyanate groups / total number of moles of hydroxyl groups) is 1.5 or more, the urethane prepolymer The viscosity is moderate, and the moisture curable hot melt adhesive has excellent coatability and further has excellent heat-resistant creep resistance after curing. When the ratio of the total number of moles of isocyanate groups (—NCO) and the total number of moles of hydroxyl groups (—OH) (total number of moles of isocyanate groups / total number of moles of hydroxyl groups) is 3 or less, an unreacted polyisocyanate compound And the foaming of the moisture curable hot melt adhesive can be suppressed during the moisture curing of the moisture curable hot melt adhesive.

  As a method for synthesizing a urethane prepolymer, for example, a urethane prepolymer is melted by heating a raw material composition containing a crystalline polyester polyol, a polyether polyol, an acrylic copolymer, and a thermoplastic polycaprolactone to 80 to 140 ° C. After the raw material composition is dehydrated under reduced pressure or the like, a polyisocyanate compound is added to the molten raw material composition in a nitrogen atmosphere, and the raw material composition and the polyisocyanate compound are reacted to make a urethane A method of synthesizing a polymer is mentioned.

(Other additives)
The moisture curable hot melt adhesive contains the urethane prepolymer, but an additive may be contained in addition to the urethane prepolymer.

  The additive is not particularly limited as long as the physical properties of the moisture curable hot melt adhesive are not impaired. For example, tackifier, oil, plasticizer, thermoplastic resin, curing catalyst, stabilizer, filler, antioxidant Agents, light stabilizers, ultraviolet absorbers, colorants, flame retardants, fragrances, pigments, dyes, and polymers having hydrolyzable silyl groups. In addition, an additive may be used independently or 2 or more types may be used together.

  Examples of the tackifier include rosin resins, terpene resins, aliphatic petroleum resins, and aromatic petroleum resins. The ring-and-ball softening point of the tackifier is preferably 90 to 150 ° C. The ring and ball softening point refers to a temperature measured according to JAI-7-1999 (Japan Adhesive Industry Association Standard). A tackifier may be used independently or 2 or more types may be used together.

  Examples of the oil include process oil, extender oil, softener, naphthenic oil, and paraffinic oil. Oils may be used alone or in combination of two or more.

  Examples of the plasticizer include phosphoric acid esters such as tributyl phosphate and tricresyl phosphate, phthalic acid esters such as dioctyl phthalate, fatty acid-basic acid esters such as glycerin monooleate, and fatty acid diacids such as dioctyl adipate. Hydrocarbon oils such as basic esters, aliphatic esters such as butyl oleate and methyl acetylricinoleate, trimellitic esters, chlorinated paraffins, alkyldiphenyls, partially hydrogenated terphenyls, process oils, epoxidized soybean oil , Epoxy plasticizer of benzyl epoxy stearate, vinyl polymers obtained by polymerizing vinyl monomers, polyalkylene glycols such as diethylene glycol dibenzoate, triethylene glycol dibenzoate, pentaerythritol ester An ester of Le and the like. A plasticizer may be used independently or 2 or more types may be used together.

  Examples of the thermoplastic resin include polyvinyl acetate, polystyrene derivatives, polyisobutene, polyolefins, polyalkylene oxides, polyurethanes, polyamides, natural rubber, polybutadiene, polyisoprene, nitrobutadiene rubber (NBR), styrene-butadiene- Styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS), styrene-ethylene-butylene-styrene block copolymer (SEBS), hydrogenated nitrobutadiene rubber (hydrogenated NBR), hydrogenated Styrene-butadiene-styrene block copolymer (hydrogenated SBS), hydrogenated styrene-isoprene-styrene block copolymer (hydrogenated SIS), and hydrogenated styrene-ethylene-butylene-styrene block copolymer (hydrogenated SEBS) ) It can be mentioned. A thermoplastic resin may be used independently or 2 or more types may be used together.

  The curing catalyst is used to improve the moisture reactivity of the moisture curable hot melt adhesive. As the catalyst, an amine curing catalyst or a tin curing catalyst is used. The amine curing catalyst is not particularly limited, but a morpholine compound is preferable. Specific examples of the morpholine compound include 2,2′-dimorpholinodiethyl ether, bis (2,6-dimethylmorpholinoethyl) ether, bis (2- (2,6-dimethyl-4-morpholino) ethyl). -(2- (4-morpholino) ethyl) amine, bis (2- (2,6-dimethyl-4-morpholino) ethyl)-(2- (2,6-diethyl-4-morpholino) ethyl) amine, tris (2- (4-morpholino) ethyl) amine, tris (2- (4-morpholino) propyl) amine, tris (2- (4-morpholino) butyl) amine, tris (2- (2,6-dimethyl-4 -Morpholino) ethyl) amine, tris (2- (2,6-diethyl-4-morpholino) ethyl) amine, tris (2- (2-ethyl-4-morpholino) ethyl) amine, And tris (2- (2-ethyl-4-morpholino) ethylamine, etc. The tin-based curing catalyst is not particularly limited, and examples thereof include stannous acid, dibutyltin dilaurate, dibutyltin dioctate, and dibutyltin diacid. Acetate, dioctyltin dilaurate, dioctyltin dioctate, dioctyltin diacetate, stannous dioctanoate, etc. The curing catalyst may be used alone or in combination of two or more.

  The stabilizer is not particularly limited, but an organic phosphorus compound is preferable. Examples of the organic phosphorus compound include tricresyl phosphate, triethyl phosphate, tributyl phosphate, tris (2-ethylhexyl) phosphate, tributoxyethyl phosphate, triphenyl phosphate, octyl diphenyl phosphate, tris ( Isopropylphenyl) phosphate, cresyl diphenyl phosphate, triphenyl phosphite, triphenyl phosphine, triphenyl phosphine oxide, aromatic phosphate condensed ester. Among these, organic phosphorus compounds that are solid at normal temperature are preferable, and triphenyl phosphite, triphenyl phosphine, triphenyl phosphine oxide, and aromatic phosphoric acid condensed esters are more preferable. According to the organic phosphorus compound, the thermal stability of the moisture curable hot melt adhesive can be improved without reducing the curing rate of the moisture curable hot melt adhesive. A stabilizer may be used independently or 2 or more types may be used together.

  Examples of the filler include, for example, silica, talc, clay, calcium carbonate, magnesium carbonate, anhydrous silicon, hydrous silicon, calcium silicate, titanium dioxide, carbon black, bentonite, organic bentonite, shirasu balloon, glass microballoon, phenol Examples thereof include organic microballoons formed from resins and vinylidene chloride resins, and particles formed from resins such as PVC (polyvinyl chloride) and PMMA (polymethyl methacrylate). A filler may be used independently or 2 or more types may be used together.

  Examples of the antioxidant include a monophenol antioxidant, a bisphenol antioxidant, and a polyphenol antioxidant. Antioxidants may be used alone or in combination of two or more.

  As the light stabilizer, for example, a hindered amine light stabilizer is preferably used. Among these, a hindered amine light stabilizer in which the amine moiety is a tertiary amine is more preferable. Examples of the light stabilizer include N, N ′, N ″, N ′ ″-tetrakis- (4,6-bis- (butyl- (N-methyl-2,2,6,6-tetramethylpiperidine). -4-yl) amino) -triazin-2-yl) -4,7-diazadecane-1,10-diamine, bis (2,2,6,6-tetramethyl-1 (octyloxy) -4 decanoate -Piperidinyl) ester, the reaction product of 1,1-dimethylethyl hydroperoxide and octane, bis (1,2,2,6,6, -pentamethyl-4-piperidyl [[3,5-bis (1,1- Dimethylethyl) -4-hydroxyphenyl] methyl] butyl malonate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate, methyl 1,2,2,6,6-pentamethyl-4 -Piperidylse Sebacate, and bis (1-octyloxy-2,2,6,6-tetramethyl-4-piperidyl) can be mentioned are. Light stabilizers such sebacate may also be alone, or two or more are used alone.

  Examples of ultraviolet absorbers include benzotriazole ultraviolet absorbers and benzophenone ultraviolet absorbers. An ultraviolet absorber may be used independently or 2 or more types may be used together.

  The polymer having a hydrolyzable silyl group has at least one crosslinkable hydrolyzable silyl group in one molecule. The hydrolyzable silyl group is a group in which the hydrolyzable group is bonded to a silicon atom. Examples of the hydrolyzable group include a hydrogen atom, a halogen atom, an alkoxy group, an acyl oxide group, a ketoximate group, an amino group, an amide group, an acid amide group, an aminooxy group, a mercapto group, and an alkenyl oxide group. It is done.

  As the hydrolyzable silyl group, an alkoxysilyl group in which an alkoxy group is bonded to a silicon atom is preferable because no harmful by-product is formed after the reaction. Examples of the alkoxy group include methoxy group, ethoxy group, propyloxy group, isopropyloxy group, butoxy group, tert-butoxy group, phenoxy group, and benzyloxy group. Of these, a methoxy group and an ethoxy group are preferable.

  Examples of the alkoxysilyl group include trialkoxysilyl groups such as trimethoxysilyl group, triethoxysilyl group, triisopropoxysilyl group and triphenoxysilyl group; dialkoxysilyl such as dimethoxymethylsilyl group and diethoxymethylsilyl group Groups; monoalkoxysilyl groups such as methoxydimethylsilyl group and ethoxydimethylsilyl group. The polymer having a hydrolyzable silyl group may have one or more of these alkoxysilyl groups.

  Preferable examples of the main chain of the polymer having a hydrolyzable silyl group include polyalkylene oxide, polyether polyol, (meth) acrylate polymer, and polyolefin. Examples of the polyalkylene oxide include polyethylene oxide, polypropylene oxide, and polybutylene oxide. Examples of the polyether polyol include polyethylene glycol, polypropylene glycol, polytetramethylene glycol, random copolymers and block copolymers thereof, and alkylene oxide adducts of bisphenol A. As a monomer which comprises a (meth) acrylate type polymer, the alkyl (meth) acrylate whose carbon number of an alkyl group becomes like this. Preferably it is 1-12, More preferably, it is 2-8. Examples of the polyolefin include homopolymers and copolymers such as ethylene and propylene, and specifically, polyethylene (for example, low density polyethylene (LDPE), medium density polyethylene (MDPE), linear low density polyethylene (LLDPE). ), Metallocene-catalyzed polyethylene, high-density polyethylene (HDPE), etc.), polypropylene (PP), ethylene-α-olefin copolymers (ethylene-propylene copolymers, etc.), and the like.

[Cosmetic materials]
The above-described moisture-curable hot melt adhesive of the present invention is suitably used for the production of a cosmetic material. The moisture curable hot melt adhesive of the present invention is preferably used for bonding and integrating the base material and the decorative sheet.

  The configuration of the decorative material is not particularly limited, and includes a configuration of a conventionally known decorative material. For example, a cosmetic material in which a base material and a decorative sheet are bonded and integrated with the moisture-curable hot melt adhesive of the present invention can be mentioned.

  Since the moisture curable hot melt adhesive has the above-described configuration, the basic performance required for the moisture curable hot melt adhesive, which is the normal performance, and the high level of heat resistance creep resistance, Since the initial adhesive strength of the sheet is excellent at high temperatures (50 ° C.), peeling and floating of the decorative sheet can be suppressed even at high temperatures in summer.

  The melt viscosity of the moisture curable hot melt adhesive is preferably 40000 mP · s or less at 120 ° C. When the melt viscosity of the moisture curable hot melt adhesive is 40000 mP · s or less, excellent workability is obtained. The melt viscosity of the moisture-curing hot melt adhesive was measured using a B-type viscometer under the conditions of a temperature of 120 ° C. and a rotation speed of 20 rpm in accordance with Japan Adhesive Industry Association Standard JAI-7-1999. Refers to the melt viscosity obtained. The B-type viscometer is commercially available from Brookfield under the trade name “B-type viscometer digital rheometer DVII (rotor No. 29)”, for example.

  As a method for producing a decorative material, for example, a moisture-curing hot melt adhesive is melted by heating to 70 to 160 ° C., and then applied onto one of a base material or a decorative sheet and applied moisture. A laminated body is obtained by superposing the other of the base material or the decorative sheet on the curable hot melt adhesive, and the moisture curable hot melt adhesive is cured by curing the laminated body, whereby the adhesive layer is formed. There is a method of forming a decorative material in which a base material and a decorative sheet are bonded and integrated with an adhesive layer while forming.

  Examples of the method for applying the heat-cured moisture-curable hot melt adhesive to the substrate or the decorative sheet include a roll coater, a spray coater, a T-die coater, and a knife coater.

  In addition, before curing the laminate, it is preferable to press the substrate, the moisture-curable hot melt adhesive, and the decorative sheet by performing a roll press, a flat press, a belt press or the like on the laminate.

  Base materials used for decorative materials include vinyl chloride resin, vinylidene chloride resin, polyethylene resin, polypropylene resin, polystyrene resin, ABS resin, polyamide resin, polyester resin, polyurethane resin, polyvinyl alcohol resin, ethylene-vinyl acetate copolymer resin Synthetic resin plates made of synthetic resin such as chlorinated polypropylene resin and melamine resin; wood such as natural wood, plywood, medium density fiber board (MDF) particle board, hard fiber board, semi-rigid fiber board, and laminated wood; Examples include inorganic boards; and metal plates made of metals such as aluminum, iron, and stainless steel. In the base material, the surface to be bonded and integrated with the adhesive layer is subjected to primer treatment such as plasma treatment, electrodeposition coating treatment such as acrylic resin or melamine acrylic resin, and alumite treatment as necessary. It may be. In addition to the groove portion, a curved surface portion such as an R portion or an inverted R portion may be formed on the base material.

  Examples of the decorative sheet include polyester, nylon, polystyrene, polycarbonate, vinyl chloride, ethylene-vinyl acetate copolymer, a sheet made of a synthetic resin such as polyvinyl alcohol, polyethylene, and polypropylene, paper, a veneer, and a metal foil. The decorativeness of the decorative sheet may be enhanced by applying a color or pattern to the surface.

  The decorative material of the present invention is preferably used as, for example, exterior materials such as flooring, wooden doors and panels, window frames, sills, handrails, skirting boards, edges, kitchens, and closets, interior materials, and furniture.

  The use point of the moisture-curing hot melt adhesive will be described. First, the moisture curable hot melt adhesive is taken out from a storage container such as an aluminum pack. Since the moisture-curable hot melt adhesive is excellent in peelability from a storage container such as an aluminum pack, it can be easily taken out from the storage container.

  Next, after the moisture curable hot melt adhesive is heated to 100 to 130 ° C. and melted, the molten moisture curable hot melt adhesive is applied to the adherend. Another adherend is superposed on the moisture curable hot melt adhesive applied to the adherend, and the two adherends are superposed via the moisture curable hot melt adhesive. At this time, the moisture curable hot melt adhesive maintains excellent initial adhesive strength over a long period of time, so that the two adherends are reliably overlaid through the moisture curable hot melt adhesive. Can be held. Furthermore, since the moisture-curing hot melt adhesive has a long open time, it is possible to easily align the two adherends.

  Thereafter, the moisture curable hot melt adhesive is cured by leaving it for 120 to 168 hours in an environment having a relative humidity of 50 to 60%, preferably at 20 to 25 ° C. Thus, the two adherends can be bonded and integrated. Since the hot melt adhesive has excellent normal adhesive strength and heat-resistant creep resistance after curing, the two adherends are stably bonded and integrated over a long period of time.

  Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited thereto.

  First, it describes about the detail of each component used for manufacture of a moisture hardening type hot-melt-adhesive in the Example and comparative example which are mentioned later.

(Crystalline polyester polyol)
・ Crystalline polyester polyol (A1)
Crystalline polyester polyol obtained by condensation polymerization of dodecanedioic acid (12 carbon atoms) and 1,6-hexanediol (6 carbon atoms) (number average molecular weight: 3600, trade name “ETERRNACOLL 3010” manufactured by Ube Industries, Ltd.)
・ Crystalline polyester polyol (A2)
Crystalline polyester polyol obtained by condensation polymerization of dodecanedioic acid (12 carbon atoms) and 1,6-hexanediol (6 carbon atoms) (number average molecular weight: 2500, trade name “ETERRNACOLL 3015” manufactured by Ube Industries, Ltd.)

(Polyether polyol)
・ Polyether polyol (B1)
Polypropylene glycol (number average molecular weight: 3000, trade name “Exenol 3020” manufactured by Asahi Glass Co., Ltd.)
・ Polyether polyol (B2)
Polypropylene glycol (number average molecular weight: 400, trade name “Exenol 420” manufactured by Asahi Glass Co., Ltd.)
・ Polyether polyol (B3)
Polypropylene glycol (number average molecular weight: 2000, trade name “EXCENOL 2020” manufactured by Asahi Glass Co., Ltd.)

(Acrylic copolymer)
Acrylic copolymer (C1) (number average molecular weight: 140000, glass transition temperature: 65 ° C., trade name “Dynacol AC1750” manufactured by Evonik Japan)
-Acrylic copolymer (C2) (number average molecular weight: 210000, glass transition temperature: 50 ° C., trade name “Dianar BR-122” manufactured by Mitsubishi Rayon)

(Thermoplastic polycaprolactone)
Thermoplastic polycaprolactone (D1) (number average molecular weight: 50000, manufactured by Perstorp, trade name “Capa6500”)
Thermoplastic polycaprolactone (D2) (number average molecular weight: 37000, manufactured by Perstorp, product name “Capa6400”)

(Polyisocyanate compound)
・ 4,4'-diphenylmethane diisocyanate

(Examples 1-13, Comparative Examples 1-8)
Predetermined amounts of crystalline polyester polyols (A1) to (A2), polyether polyols (B1) to (B3), acrylic copolymers (C1) to (C2), and heat shown in Table 1 and Table 2 Plastic polycaprolactones (D1) to (D2) were put into a 1-liter four-necked flask having a stirring blade, heated to 140 ° C. and melted to obtain a raw material composition in a molten state.

  The obtained raw material composition was dehydrated under a reduced pressure of 133.3 Pa (1 mmHg) or less, and then the inside of the flask was purged with nitrogen gas to cool the raw material composition to 80 ° C. Next, a predetermined amount of 4,4'-diphenylmethane diisocyanate shown in Table 1 was added to the raw material composition in the flask. In the total amount of the raw material composition and 4,4′-diphenylmethane diisocyanate, the ratio of the total number of moles of isocyanate groups (—NCO) to the total number of moles of hydroxyl groups (—OH) (total moles of isocyanate groups / total moles of hydroxyl groups) The numbers are shown in Tables 1 and 2.

  The inside of the flask was stirred and reacted for 3 hours under a nitrogen gas atmosphere to obtain a moisture curable hot melt adhesive containing a urethane prepolymer containing an isocyanate group at the terminal.

  About the obtained moisture hardening type hot melt adhesive, the melt viscosity at 120 ° C., the initial creep test (initial adhesive strength), the normal state adhesive strength and the heat resistant creep test were measured as follows, and the results are shown in Table 1 and Table 1. It was shown in 2.

(Melt viscosity)
Using a B-type viscometer commercially available from Brookfield under the trade name “B-type viscometer digital rheometer DVII (rotor No. 29)”, the temperature is 120 in accordance with Japan Adhesive Industry Association Standard JAI-7-1999. The measurement was performed under the condition of ° C.
40000 mP · s or less was designated as “◯”, and 40000 mP · s or more as “x”.

(Initial creep test (initial adhesive strength))
After the moisture curable hot melt adhesive is heated to 120 ° C. and melted, the molten moisture curable hot melt adhesive is applied to one surface of a planar rectangular olefin sheet (thickness 180 μm) with a coating thickness of 50 μm. Worked. Then, after superposing the olefin sheet on the medium density fiber (medium density fiber board, hereinafter referred to as MDF) base material, the surface temperature of which was adjusted to 50 ° C., through the applied moisture curable hot melt adhesive, A test piece was obtained by rolling a rubber roll on the olefin sheet to press-bond the olefin sheet and the MDF substrate.

  In a 50 ° C. atmosphere, the test piece was placed horizontally such that the olefin sheet was on the bottom surface, and then a load of 12 g / 30 mm was applied in the vertical direction to one end in the length direction of the olefin sheet. After 5 minutes passed in this state, the length (mm) at which the olefin sheet was peeled was measured.

(Normal adhesive strength)
After the moisture curable hot melt adhesive is heated to 120 ° C. and melted, the molten moisture curable hot melt adhesive is applied to one surface of a planar rectangular olefin sheet (thickness 180 μm) with a coating thickness of 50 μm. Worked. Then, after superposing the olefin sheet on the MDF base material whose surface temperature was adjusted to 40 ° C. via the coated moisture-curable hot melt adhesive, rolling the rubber roll on the olefin sheet, A test piece was obtained by pressure bonding the sheet and the MDF substrate.

  Next, the moisture-curable hot melt adhesive was cooled and solidified by leaving the test piece in an environment of 23 ° C. and 55% relative humidity for 1 hour. Thereafter, the test piece was left to stand in an environment of a temperature of 23 ° C. and a relative humidity of 55% for one week to cure the moisture-curable hot melt adhesive. Then, the olefin sheet was peeled from the MDF substrate at a peeling angle of 180 degrees and a peeling speed of 200 mm / min, and the average peel strength at this time was measured as “normal adhesive strength (N / 25 mm)”.

(Heat resistant creep test)
In the same manner as in the above procedure for measuring the normal adhesive strength, a test piece was prepared and the moisture-curable hot melt adhesive of the test piece was moisture-cured. In a temperature environment of 60 ° C., the test piece was placed horizontally so that the olefin sheet was on the lower surface, and then one end in the length direction of the olefin sheet was applied with a weight of 500 g / 25 mm in the vertical direction. . After the lapse of 24 hours in this state, the length (mm) at which the olefin sheet was peeled was measured.

Claims (2)

Crystalline polyester polyol 20-30 mass%, polyether polyol 35-40 mass%, which is a condensation polymer of linear polycarboxylic acid having 12 carbon atoms and linear polyol having 6 carbon atoms, glass transition It is a reaction product of a raw material composition containing 15 to 25% by mass of an acrylic copolymer having a temperature of 50 to 90 ° C. and 3 to 7% by mass of thermoplastic polycaprolactone and a polyisocyanate compound, and is terminated with an isocyanate. In the raw material composition, the crystalline polyester polyol, the polyether polyol, the acrylic copolymer, the thermoplastic polycaprolactone, and the polyisocyanate compound. Moisture-curing hot melt contact characterized in that the total amount is 100% by mass Agent. The moisture-curable hot melt adhesive according to claim 1, wherein the melt viscosity at 120 ° C is 40000 mPa · s or less.