JP2011116830A - Pressure-sensitive adhesive composition, pressure-sensitive adhesive layer and pressure-sensitive adhesive laminated product - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive composition capable of forming a pressure-sensitive adhesive layer excellent in flame retardancy as well as in self-adhesive properties and transparency, a pressure-sensitive adhesive layer, and a pressure-sensitive adhesive laminated product provided with a pressure-sensitive adhesive layer. <P>SOLUTION: The pressure-sensitive adhesive composition comprises a (meth)acrylic acid ester polymer comprising a recurring unit composed of a (meth)acrylic acid ester bearing a phosphoric acid ester group and a recurring unit composed of a (meth)acrylic acid ester bearing a 1-18C alkyl group, and an amine compound. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive adhesive composition, a pressure-sensitive adhesive layer, and a pressure-sensitive adhesive laminate.

  For example, electronic parts or materials constituting them are often required to pass the UL standard as safety standards, and among them, the flame retardant standard is often required. For example, electrical insulating tapes used for electronic parts and the like are required to have high flame resistance characteristics that pass UL94 standard as UL standard. In order to impart flame retardancy to this tape, conventionally known are those using halogen compounds such as chlorine and bromine as flame retardants, and systems using both halogen compounds and antimony oxide. However, when a halogen-based compound is used as a flame retardant, there is a problem that a halogen-based gas that adversely affects the human body during combustion is a problem, and a method for making flame retardant without using a halogen-based compound is required. ing.

  The same is a problem in the flame-retardant of pressure-sensitive adhesives, and a method of flame-retarding without using a halogen-based compound has been studied. Thus, pressure-sensitive adhesives and pressure-sensitive adhesive sheets using phosphorus compounds such as ammonium polyphosphate, melamine polyphosphate, red phosphorus, and phosphate esters as flame retardants have been proposed (for example, see Patent Documents 1 to 4). However, when a phosphorus compound as described above is added, there is a problem in that the physical properties of the adhesive are deteriorated and the adherend is deteriorated. Further, depending on the type of phosphorus compound, an aggregate may be generated in the pressure-sensitive adhesive. In the case where aggregates are generated in the pressure-sensitive adhesive, the pressure-sensitive adhesive layer formed by applying the pressure-sensitive adhesive becomes opaque, and there is a problem that the use is limited.

Japanese Patent No. 3498124 JP 2000-169811 A Japanese Patent Laid-Open No. 2001-271044 JP 2006-219564 A

  The present invention provides a pressure-sensitive adhesive composition, a pressure-sensitive adhesive layer, and a pressure-sensitive adhesive layer capable of forming a pressure-sensitive adhesive layer having excellent flame retardancy and excellent tackiness and transparency. An object is to provide an adhesive laminate.

  As a result of intensive studies to achieve the above object, the present inventors have included a (meth) acrylic acid ester-based polymer having a phosphoric acid ester group and an amine compound, thereby providing flame retardancy, It has been found that a pressure-sensitive adhesive composition that can form a pressure-sensitive adhesive layer excellent in tackiness and transparency, a pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive layer and a pressure-sensitive adhesive layer can be obtained, The present invention has been completed.

  1st aspect of this invention which solves the said subject consists of a repeating unit which consists of (meth) acrylic acid ester which has a phosphate ester group, and (meth) acrylic acid ester which has a C1-C18 alkyl group. A pressure-sensitive adhesive composition comprising: a (meth) acrylic acid ester-based polymer containing a repeating unit; and an amine-based compound.

  2nd aspect of this invention mix | blends so that the total amount of the said amine-type compound may be 0.1-50 mass parts with respect to 100 mass parts of said (meth) acrylic acid ester-type polymers. In the pressure-sensitive adhesive composition according to the first aspect,

  According to a third aspect of the present invention, in the first or second aspect, the repeating unit comprising the (meth) acrylic acid ester having a phosphate ester group is represented by the following general formula (1). In the pressure-sensitive adhesive composition described.

(In General Formula (1), A is an alkylene group having 1 to 8 carbon atoms, R ₁ is H or CH ₃ , and R ₂ and R ₃ are each independently H, C _n H _{2n + 1} (n = 1 To 8), or a group represented by C ₆ H _m (CH ₃ ) _5-m (m = 0 to 5).

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the amine compound is at least one of a secondary amine compound, a tertiary amine compound, an amidine compound, and a guanidine compound. In a pressure sensitive adhesive composition as described in one embodiment.

  According to a fifth aspect of the present invention, in the (meth) acrylic acid ester-based polymer, the proportion of repeating units composed of the (meth) acrylic acid ester having a phosphate group is 10 to 50 mol%. The pressure-sensitive adhesive composition according to any one of the first to fourth aspects is characterized.

  6th aspect of this invention exists in the pressure sensitive adhesive layer which consists of a crosslinked material of the pressure sensitive adhesive composition as described in any one 1st-5th aspect.

  According to a seventh aspect of the present invention, there is provided a pressure-sensitive adhesive laminate comprising the pressure-sensitive adhesive layer according to the sixth aspect on at least one surface of a substrate.

  The pressure-sensitive adhesive composition of the present invention includes a repeating unit composed of a (meth) acrylic acid ester having a phosphate ester group and a repeating unit composed of a (meth) acrylic acid ester having an alkyl group having 1 to 18 carbon atoms. , A (meth) acrylic acid ester-based polymer, and an amine-based compound, which can form a pressure-sensitive adhesive layer having excellent flame retardancy and excellent tackiness and transparency. is there. Moreover, such a pressure-sensitive adhesive composition can prevent a decrease in pressure-sensitive physical properties and deterioration of an adherend. In addition, a pressure-sensitive adhesive layer and a pressure-sensitive adhesive laminate having both flame retardancy, tackiness, and transparency can be provided.

  Hereinafter, the present invention will be described in detail by classifying into (1) a pressure-sensitive adhesive composition, (2) a pressure-sensitive adhesive layer, and (3) a pressure-sensitive adhesive laminate.

(1) Pressure-sensitive adhesive composition The pressure-sensitive adhesive composition of the present invention has a repeating unit composed of (meth) acrylic acid ester having a phosphate ester group and an alkyl group having 1 to 18 carbon atoms (meta ) A (meth) acrylate polymer containing a repeating unit made of an acrylate ester and an amine compound.

  In addition, (meth) acrylic acid is a general term for acrylic acid or methacrylic acid, and other “(meth)” conforms to this. Moreover, a polymer shall be a general term for a homopolymer and a copolymer.

  The (meth) acrylic acid ester polymer according to the present invention comprises a repeating unit composed of a (meth) acrylic acid ester having a phosphate group (hereinafter referred to as “monomer (A)”), and a carbon number of 1 to 1. And a repeating unit composed of a (meth) acrylic acid ester having 18 alkyl groups (hereinafter referred to as “monomer (B)”). This (meth) acrylic acid ester polymer is a copolymer of a (meth) acrylic acid ester having a phosphoric acid ester group and a (meth) acrylic acid ester having a C 1-18 alkyl group. However, it may be copolymerized with other monomers, and is preferably copolymerized with a monomer having a crosslinkable functional group in the molecule. The (meth) acrylic acid ester polymer is obtained by polymerizing a (meth) acrylic acid ester monomer having an appropriate functional group to form the main chain portion of the (meth) acrylic acid ester polymer. The compound having a suitable functional group and a phosphate ester group may be reacted to introduce a phosphate ester group into the main chain of the polymer.

  Examples of the repeating unit composed of the monomer (A) include a repeating unit represented by the following general formula (1). By including the repeating unit composed of the monomer (A), the flame retardancy can be improved, and the adhesiveness and transparency can be improved. Moreover, by including the repeating unit represented by the following general formula (1), the pressure-sensitive adhesive composition is more excellent in flame retardancy.

(In General Formula (1), A is an alkylene group having 1 to 8 carbon atoms, R ₁ is H or CH ₃ , and R ₂ and R ₃ are each independently H, C _n H _{2n + 1} (n = 1 To 8), or a group represented by C ₆ H _m (CH ₃ ) _5-m (m = 0 to 5).

  Specific examples of the monomer (A) that forms the repeating unit represented by the general formula (1) include (meth) acryloyloxyethyl diethyl phosphate, (meth) acryloyloxyethyldipropyl phosphate, (meth) acryloyloxy. Examples thereof include ethyl diphenyl phosphate, (meth) acryloyloxymethyl phosphate, (meth) acryloyloxyethyl phosphate, (meth) acryloyloxypropyl phosphate, (meth) acryloyloxypentyl phosphate, (meth) acryloyloxyhexyl phosphate and the like. These may be used alone or in combination of two or more.

  The monomer (B) includes methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, (meth ) Pentyl acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate, (meth) acrylate n Nonyl, isononyl (meth) acrylate, decyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, myristyl (meth) acrylate (Meth) acrylic acid such as palmitic acid (meth) acrylate and stearyl (meth) acrylate Mention may be made of the ether and the like. These may be used alone or in combination of two or more. By including a repeating unit composed of the monomer (B), a pressure-sensitive adhesive composition having excellent tackiness can be obtained.

  The other monomer is not particularly limited as long as it is a compound copolymerizable with the monomer (A) or the monomer (B), but a monomer having a crosslinkable functional group in the molecule is not limited. Polymerization is preferred.

  In the (meth) acrylic acid ester polymer according to the present invention, at least one of the monomers (A) and (B) and other monomers copolymerized as necessary has a crosslinkable functional group. It is preferable to make it. By having a crosslinkable functional group, it can react with a crosslinking agent to form a pressure sensitive adhesive layer.

  As the monomer having a crosslinkable functional group in the molecule, those containing at least one of a hydroxyl group, a carboxyl group, an isocyanate group, and an epoxy group as the functional group are preferable. Specific examples of the monomer having a crosslinkable functional group in the molecule include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, (meth ) (Meth) acrylic acid hydroxyalkyl esters such as 2-hydroxybutyl acrylate, 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate; monomethylaminoethyl (meth) acrylate, (meth) Monoethylaminoalkyl (meth) acrylates such as monoethylaminoethyl acrylate, monomethylaminopropyl (meth) acrylate, monoethylaminopropyl (meth) acrylate; acrylic acid, methacrylic acid, crotonic acid, maleic acid, itacon Examples thereof include ethylenically unsaturated carboxylic acids such as acid and citraconic acid. These monomers may be used independently and may be used in combination of 2 or more type.

  In the present invention, as the other monomer, a monomer having no crosslinkable functional group may be copolymerized. Examples of such monomers include aromatic vinyl compounds such as vinyl benzoic acid, styrene, and α-methyl styrene; vinyl ether compounds such as vinyl glycidyl ether; (meth) acrylamide, N-methyl (meth) acrylamide, and N-methylol. (Meth) acrylamide compounds such as (meth) acrylamide; Nitrile compounds such as (meth) acrylonitrile; butadiene, isoprene and the like.

  The (meth) acrylic acid ester polymer according to the present invention preferably has a weight average molecular weight (Mw) of 10,000 to 1,000,000, more preferably 60,000 to 900,000. Thereby, it can be set as the pressure sensitive adhesive composition which can prevent a bleed out and can form the pressure sensitive adhesive layer excellent in adhesive physical property. In addition, a weight average molecular weight means what was obtained by measuring by GPC (gel permeation chromatography).

  In the (meth) acrylic acid ester polymer according to the present invention, the copolymerization ratio of the monomer (A) is preferably 10 to 50 mol%, more preferably 15 to 40 mol%, particularly preferably. It is 20-30 mol%. By setting the copolymerization ratio of the monomer (A) to 10 mol% or more, the flame retardancy is excellent.

  In addition, the (meth) acrylic acid ester-type polymer concerning this invention can be manufactured by arbitrary well-known polymerization methods, such as solution polymerization and block polymerization. Examples of the initiator used in the polymerization include azobisisobutylnitrile, benzoyl peroxide, di-t-butyl peroxide, cumene hydroperoxide and the like.

  The form of the copolymer is not particularly limited, and any of random, block, and graft copolymers may be used.

  In the present invention, by adding an amine compound, the phosphate compound is trapped even if the phosphate compound is desorbed from the (meth) acrylate polymer having a phosphate group over time. can do.

  Examples of the amine compound according to the present invention include primary amine compounds, secondary amine compounds, tertiary amine compounds, imidazole compounds, amidine compounds, and guanidine compounds.

  Examples of the primary amine compound include methylamine, ethylamine, butylamine, S-butylamine, t-butylamine, amylamine, octylamine, allylamine, ethoxymethylamine, benzylamine, cyclohexylamine and the like. As the secondary amine compound, piperidine, piperidine derivatives (for example, LA-57, LA-67, LA-68LD, LA-77Y; manufactured by ADEKA), dimethylamine, diethylamine, dipropylamine, diallylamine, dihexylamine, Examples include didodecylamine and hexamethylenetetramine. Tertiary amine compounds include N, N, N ′, N′-tetramethylethylenediamine, 1,4-diazabicyclo [2.2.2] octane, 1,8-diazabicyclo [5.4.0] undeca- 7-ene (DBU), N-ethylmorpholine, piperidine derivatives (for example, LA-52, LA-62, LA-63P, LA-81; manufactured by ADEKA), trimethylamine, triethylamine, tripropylamine, 4-dimethylamino Examples include pyridine. Examples of the imidazole compound include N-methylimidazole, 2-methylimidazole, N-vinylimidazole, 1,2-dimethylimidazole, 2-phenylimidazole and the like. Examples of amidine compounds include acetamidine, benzamidine, N, N′-diphenylformamidine, and the like. Guanidine compounds include guanidine, triphenylguanidine, tricyclohexylguanidine, 1,3-dicyclohexyl-2-phenylguanidine, 1,1,3,3-tetramethylguanidine, 1,2,3-triphenylguanidine, 1, Examples include 3-diphenylguanidine.

  Among these, secondary amine compounds, tertiary amine compounds, amidine compounds and guanidine compounds are preferable, and secondary amine compounds and tertiary amine compounds are particularly preferable. This is because it has a strong basicity and has a high ability to trap phosphoric acid compounds produced by elimination and the like, and it is possible to further suppress changes in adhesive properties over time.

  The pressure-sensitive adhesive composition of the present invention is a total amount of the amine compound with respect to 100 parts by mass of the (meth) acrylic acid ester polymer composed of the monomer (A) and the monomer (B). Is preferably blended so as to be 0.1 to 50 parts by mass, particularly preferably 1 to 30 parts by mass. Thereby, it can be set as the pressure-sensitive-adhesive composition which forms the pressure-sensitive-adhesive layer with a small time-dependent change of adhesive physical property. If the compounding ratio of the amine compound to the (meth) acrylic acid ester polymer is too low, the desired effect may not be sufficiently obtained. If the compounding ratio of the amine compound is too high, bleeding may occur. There is a risk of reducing the adhesive strength.

  Furthermore, the pressure-sensitive adhesive composition includes an ultraviolet absorber, a softening agent (plasticizer), a curing accelerator, a filler, an anti-aging agent, a tackifier, a pigment, a dye, a coupling agent, and the like as necessary. Various additives can be added. Examples of the tackifier include rosin and derivatives thereof, polyterpene, terpene phenol resin, coumarone-indene resin, petroleum resin, styrene resin, xylene resin and the like. Examples of the softening agent include liquid polyether, glycol ester, liquid polyterpene, liquid polyacrylate, phthalic acid ester, trimellitic acid ester, and the like.

  Furthermore, the pressure-sensitive adhesive composition may contain a solvent such as an organic solvent as required. When the pressure-sensitive adhesive composition contains a solvent, the concentration of the solid component ((meth) acrylic acid ester-based polymer having a phosphate group, cross-linking agent) is not particularly limited, and is applied directly to a predetermined substrate. Even if it is the density | concentration which can be processed, the density | concentration used by diluting in the case of coating may be sufficient.

  Examples of such solvents include ketone solvents such as acetone, methyl ethyl ketone, diethyl ketone, methyl isobutyl ketone, and cyclohexanone; ester solvents such as ethyl acetate, propyl acetate, and butyl acetate; 1,2-dimethoxyethane, tetrahydrofuran, 1,4- Ether solvents such as dioxane; halogen solvents such as chloroform, carbon tetrachloride and chlorobenzene; aromatic hydrocarbon solvents such as benzene, toluene and xylene; N, N-dimethylformamide, N, N-dimethylacetamide, Amide solvents such as N-methylpyrrolidone; Aliphatic hydrocarbon solvents such as pentane, hexane and heptane; Alicyclic hydrocarbon solvents such as cyclopentane and cyclohexane; and a mixed solvent composed of two or more of these solvents And so on.

  After the pressure-sensitive adhesive composition of the present invention is diluted as necessary, it is applied to a predetermined substrate and crosslinked to form a pressure-sensitive adhesive layer. In addition, when applying a pressure sensitive adhesive composition, it is preferable to adjust a density | concentration using these organic solvents etc. for viscosity adjustment. The concentration is preferably adjusted to be in the range of 10 to 60% by mass.

(2) Pressure-sensitive adhesive layer The pressure-sensitive adhesive layer of the present invention comprises a crosslinked product of the pressure-sensitive adhesive composition described above.

  The type of the crosslinking agent is not particularly limited, and specific examples include isocyanate compounds, epoxy compounds, metal chelate compounds, melamine resins, aziridine compounds, metal alkoxides, metal salts and the like. From the viewpoint of obtaining an appropriate cohesive force, an isocyanate compound or an epoxy compound is particularly preferably used. These compounds may be used alone or in combination of two or more.

  As the isocyanate compound, lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; alicyclic isocyanates such as cyclopentylene diisocyanate, cyclohexylene diisocyanate and isophorone diisocyanate; 2,4-tolylene diisocyanate, 4,4 '-Diphenylmethane diisocyanate, aromatic diisocyanates such as xylylene diisocyanate; trimethylolpropane / tolylene diisocyanate 3 adduct (for example, Nippon Polyurethane Industry, trade name: Coronate L, Toyo Ink, trade name: BHS- 8515, manufactured by Soken Chemical Co., Ltd., trade name: L-45), trimethylolpropane / hexamethylene diisocyanate 3 adduct (for example, Nippon Polyurethane Industry) Ltd., trade name: Coronate HL), an isocyanurate of hexamethylene diisocyanate (for example, Nippon Polyurethane Industry Co., Ltd., trade name: Coronate HX) isocyanate adducts and the like; and the like. These isocyanate compounds may be used alone or in combination of two or more.

  Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine (for example, Mitsubishi Gas Chemical Company, trade name: TETRAD-X), and 1,3-bis (N, N-dioxy). Examples include glycidylaminomethyl) cyclohexane (for example, trade name: TETRAD-C manufactured by Mitsubishi Gas Chemical Company, Inc.). These compounds may be used alone or in combination of two or more.

  These crosslinking agents may be previously contained in the pressure-sensitive adhesive composition of the present invention. The amount of these crosslinking agents used is preferably 0.01 to 15 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid ester polymer having a phosphate group according to the present invention, More preferably, 0.5 to 5 parts by mass is contained. By setting the crosslinking agent in the above range, good adhesion and durability can be obtained. When the content of the cross-linking agent is less than 0.01 parts by mass, the cross-linking is insufficient and the cohesive force of the pressure-sensitive adhesive composition is reduced, which may cause adhesive residue. On the other hand, when the content is more than 15 parts by mass, the cohesive force is increased, the fluidity is lowered, the wetness to the adherend is insufficient, and peeling may be caused.

(3) Pressure-sensitive adhesive laminate The pressure-sensitive adhesive laminate of the present invention has the pressure-sensitive adhesive layer of the present invention on at least one side of a substrate. The base material here includes a release sheet in addition to the base base material.

  In addition, you may have a base base material as a support body, and it does not need to have it. Specific examples include those having a pressure-sensitive adhesive layer on at least one side of the base substrate, and those having a pressure-sensitive adhesive layer on the release treatment surface of the release sheet instead of the base substrate. Moreover, you may stick a peeling sheet on a pressure sensitive adhesive layer as needed. The release sheet can protect the pressure-sensitive adhesive layer

  The base substrate is not particularly limited. For example, in addition to sheet-like plastic materials such as polyvinyl alcohol, triacetyl cellulose, polymethyl methacrylate, polycarbonate, polysulfone resin, polynorbornene resin, polyethylene, polypropylene, polyethylene Resin film such as terephthalate, polyvinyl chloride, ethylene / vinyl acetate copolymer, polyurethane, polystyrene, polyimide, etc., the surface of plastic film coated with resin such as polyimide, paper such as impregnated paper, metal foil, woven fabric, Nonwoven fabrics or laminates thereof can be mentioned. The base substrate is appropriately selected depending on the use of the pressure-sensitive adhesive laminate. The thickness of such a base substrate is usually 6 to 300 μm, preferably 12 to 200 μm.

The release sheet is not particularly limited, and it is possible to use a sheet such as paper or film that has been subjected to a release treatment with a release agent. Examples of the paper include high-density base paper such as glassine paper, clay-coated paper, kraft paper, or paper obtained by laminating a film such as polyethylene on high-quality paper. Examples of the film include a film made of a resin such as polyethylene terephthalate, polypropylene, polyethylene, or a foamed film thereof. Examples of the release agent include a fluororesin, a silicone resin, and a long chain alkyl group-containing carbamate resin. A release agent is suitably used as a release sheet by applying a release agent to a sheet so that the dry mass is about 0.1 to 3 g / m ² and providing a release layer by heat curing or UV curing.

A method for producing the pressure-sensitive adhesive laminate of the present invention will be described.
First, the pressure sensitive adhesive composition is diluted with an organic solvent system to prepare a pressure sensitive adhesive composition coating solution.

  Then, the obtained pressure-sensitive adhesive composition coating liquid may be directly applied to the surface of the base substrate to form a pressure-sensitive adhesive layer on the base substrate, or the pressure-sensitive adhesive layer may be formed on the release sheet. A pressure-sensitive adhesive composition coating solution is applied to form a pressure-sensitive adhesive layer, which is then attached to a base substrate, and the pressure-sensitive adhesive layer is transferred to the base substrate or another release sheet. May be. The method for applying the pressure-sensitive adhesive composition onto the substrate is not particularly limited, and examples thereof include a roll knife coater, a die coater, a roll coater, a bar coater, a gravure roll coater, a reverse roll coater, and a dipping method. . After applying the pressure-sensitive adhesive composition coating liquid by these methods, the pressure-sensitive adhesive layer may be heat-treated to remove the solvent and promote crosslinking, and the heat treatment temperature is, for example, 50-150 ° C. The thickness of the pressure-sensitive adhesive layer formed by crosslinking the pressure-sensitive adhesive composition is preferably about 1 to 200 μm and more preferably about 10 to 100 μm in a dry state.

  The pressure-sensitive adhesive laminate of the present invention comprises a pressure-sensitive adhesive layer composed of a crosslinked product of the pressure-sensitive adhesive composition described above, and is excellent in flame retardancy, tackiness and transparency. . The pressure-sensitive adhesive layer in the pressure-sensitive adhesive composition preferably has a haze value of 5% or less measured according to JIS K 7136 standard.

  The pressure-sensitive adhesive laminate of the present invention can be suitably used as an electronic member or a material constituting them. Moreover, it is suitable for use in exteriors of electrical products, building materials, automobile parts, labels for handling fire, and the like.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further more concretely, these do not restrict | limit the scope of the present invention at all.

Example 1
In a reaction vessel equipped with a stirrer, reflux condenser, nitrogen inlet, and thermometer, 47 parts by mass (0.36 mol) of n-butyl acrylate as monomer (B), 3 mass of 2-hydroxyethyl acrylate Parts (0.025 mol), methacryloyloxyethyl diphenyl phosphate (manufactured by Daihachi Chemical Industry: MR-260) as a monomer (A) 50 parts by mass (0.13 mol), azobisisobutyronitrile 0.3 Part by mass and 150 parts by mass of ethyl acetate were added, and nitrogen substitution was performed at room temperature for 1 hour. Then, it heated up at 70 degreeC and superposition | polymerization was performed for 8 hours. When the obtained polymer was subjected to molecular weight measurement by GPC (polystyrene conversion), the weight average molecular weight (Mw) was 650,000.

  With respect to 100 parts by mass of the resulting polymerization solution, 1.0 part by mass of an isocyanate-based crosslinking agent (manufactured by Toyo Ink Manufacturing Co., Ltd .: BHS8515, solid content 37.5% by mass), 1,4-diazabicyclo as an amine compound [2.2.2] Octane (manufactured by Wako Pure Chemical Industries, Ltd .: 100% by mass) 0.4 parts by mass was added to obtain a pressure-sensitive adhesive composition.

  This composition is applied to a polyethylene terephthalate (PET) film (Toray Co., Ltd .: Lumirror 50T60) with a thickness of 50 μm using an applicator, heated and dried at 90 ° C. for 1 minute, and pressure-sensitive adhesive with a thickness of about 20 μm. A pressure sensitive adhesive laminate was prepared by laminating a release film (PIN 381031 manufactured by Lintec Corporation) on the surface of this layer.

(Example 2)
Instead of 1,4-diazabicyclo [2.2.2] octane, a piperidine derivative (manufactured by ADEKA: LA-63P, solid content: 100% by mass) was used in the same manner as in Example 1 except that 0.4 parts by mass was used. A pressure sensitive adhesive laminate was prepared.

(Example 3)
Instead of 1,4-diazabicyclo [2.2.2] octane, the same procedure as in Example 1 was carried out except that 0.4 parts by mass of 2-methylimidazole (manufactured by Wako Pure Chemical Industries, Ltd .: solid content: 100% by mass) was used. A pressure sensitive adhesive laminate was prepared.

Example 4
In the same manner as in Example 1 except that 4 parts by mass of a piperidine derivative (ADEKA: LA-63P, solid content: 100% by mass) was used instead of 1,4-diazabicyclo [2.2.2] octane. A pressure-bonding laminate was produced.

(Example 5)
A pressure-sensitive adhesive laminate was produced in the same manner as in Example 1 except that 47 parts by mass of 2-ethylhexyl acrylate was used instead of n-butyl acrylate.

(Example 6)
A pressure-sensitive adhesive laminate was produced in the same manner as in Example 1 except that a polyimide (PI) film having a thickness of 25 μm (manufactured by Toray DuPont: Kapton 100H) was used instead of the PET film.

(Example 7)
A pressure-sensitive adhesive laminate was produced in the same manner as in Example 2 except that a 25 μm thick PI film (manufactured by Toray DuPont: Kapton 100H) was used instead of the PET film.

(Example 8)
A pressure-sensitive adhesive laminate was produced in the same manner as in Example 3 except that a 25 μm-thick PI film (manufactured by Toray DuPont: Kapton 100H) was used instead of the PET film.

Example 9
A pressure-sensitive adhesive laminate was prepared in the same manner as in Example 4 except that a 25 μm thick PI film (Toray DuPont: Kapton 100H) was used instead of the PET film.

(Example 10)
A pressure-sensitive adhesive laminate was prepared in the same manner as in Example 5 except that a 25 μm-thick PI film (manufactured by Toray DuPont: Kapton 100H) was used instead of the PET film.

(Comparative Example 1)
In a reaction vessel equipped with a stirrer, reflux condenser, nitrogen inlet, and thermometer, 45 parts by mass of n-butyl acrylate, 50 parts by mass of 2-ethylhexyl acrylate, 3 parts by mass of acrylic acid, 2-hydroxyethyl acrylate 2 Part by mass, 0.3 part by mass of azobisisobutyronitrile, and 150 parts by mass of ethyl acetate were added, and nitrogen substitution was performed over 1 hour. Then, it heated up at 60 degreeC and superposed | polymerized for 8 hours. Mw of the obtained polymer was 600,000. To 100 parts by mass of the obtained polymerization solution, 1 part by mass of tolylene diisocyanate crosslinking agent (Toyo Ink Manufacturing Co., Ltd .: BHS8515, solid content concentration 37.5% by mass) and phosphate ester flame retardant (bisphenol) 10 parts by mass of A bis (diphenyl phosphate) (manufactured by Daihachi Chemical Co., Ltd .: CR-741, solid content 100% by mass) was added to obtain a pressure-sensitive adhesive composition.

  This composition is applied to a polyethylene terephthalate (PET) film (Toray Co., Ltd .: Lumirror 50T60) with a thickness of 50 μm using an applicator, heated and dried at 90 ° C. for 1 minute, and pressure-sensitive adhesive with a thickness of about 20 μm. A pressure sensitive adhesive laminate was prepared by laminating a release film (PIN 381031 manufactured by Lintec Corporation) on the surface of this layer.

(Comparative Example 2)
A pressure-sensitive adhesive laminate was produced in the same manner as in Comparative Example 1 except that the phosphate ester flame retardant was changed to 20 parts by mass.

(Comparative Example 3)
A pressure-sensitive adhesive laminate was prepared in the same manner as in Example 1 except that 1,4-diazabicyclo [2.2.2] octane was not used.

(Comparative Example 4)
A pressure-sensitive adhesive laminate was prepared in the same manner as in Comparative Example 1 except that a polyimide (PI) film having a thickness of 25 μm (Toray DuPont: Kapton 100H) was used instead of the PET film.

(Comparative Example 5)
A pressure-sensitive adhesive laminate was prepared in the same manner as in Comparative Example 2 except that a polyimide (PI) film (Toray DuPont: Kapton 100H) having a thickness of 25 μm was used instead of the PET film.

(Comparative Example 6)
A pressure-sensitive adhesive laminate was prepared in the same manner as in Comparative Example 3 except that a polyimide (PI) film having a thickness of 25 μm (manufactured by Toray DuPont: Kapton 100H) was used instead of the PET film.

  Evaluation of the pressure-sensitive adhesive laminates of the above Examples and Comparative Examples was performed as follows. The results are shown in Table 1 for the base substrate using the PET film and Table 2 for the PI film.

<Flame retardance evaluation>
In the flammability test, the release film of the pressure-sensitive adhesive laminate was peeled off, and the UL94VTM rank was determined based on the vertical flammability test method of the flammability test standard UL94 issued by Underwriters Laboratories.

<Adhesive strength change>
The pressure-sensitive adhesive laminate was measured for adhesion to an SUS plate after being accelerated at 23 ° C. × 50% RH and 70 ° C. × Dry for 7 days according to JIS Z 0237. And the change rate of the adhesive force was computed. In addition, the case where the change rate of the adhesive force of the pressure-sensitive adhesive laminate for test was less than 20% was evaluated as ◯, the case where it was 20 to 50% was evaluated as Δ, and 50% or more was evaluated as ×.

<Transparency evaluation>
The release film of the pressure-sensitive adhesive laminate is peeled off, and the haze value of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive laminate based on the PET film is measured using a visible light transmittance measuring device (Nippon Denshoku Industries Co., Ltd.). Manufactured by Haze Meter NDH2000) and measured according to JIS K 7136 standard. The light incident surface was the pressure sensitive adhesive layer surface.

(Summary of results)
The pressure-sensitive adhesive laminates of Examples 1 to 5 using a PET film as the base substrate have a flame retardancy evaluation determination of VTM-2, which is excellent in flame retardancy, and the rate of change in adhesive strength is It was less than 20%. Further, the haze value was 1.2% or less, and the transparency was excellent.

  On the other hand, the pressure-sensitive adhesive laminates of Comparative Example 3 and Comparative Example 6 that did not contain an amine compound had a large decrease in adhesive strength after the accelerating conditions. This is presumably because the phosphate compound was eliminated from the repeating unit consisting of (meth) acrylic acid ester having a phosphate ester group. In addition, Comparative Example 1 and Comparative Example 4 that do not include any repeating unit or amine compound composed of (meth) acrylic acid ester having a phosphate ester group and have a small amount of the phosphate ester flame retardant are after the promotion conditions. It is considered that the adhesive strength was greatly reduced and the adhesive strength was reduced by bleeding out of the phosphate ester flame retardant. Furthermore, in Comparative Example 2 and Comparative Example 5 in which a large amount of phosphate ester flame retardant is blended, although the flame retardant is excellent, the pressure sensitive adhesive and the phosphate ester flame retardant are not compatible, so the flame retardant is pressure sensitive. Since it was localized in the adhesive, the adhesive strength was low and it could not be used.

  In addition, the pressure-sensitive adhesive laminates of Examples 6 to 10 using a PI film as a base substrate are very excellent in flame retardancy and have no change in adhesive strength, and no agglomerates are confirmed. There wasn't.

As mentioned above, (meth) acrylic acid containing the repeating unit which consists of a (meth) acrylic acid ester which has a phosphate ester group, and the repeating unit which consists of a C1-C18 alkyl group (meth) acrylic acid ester A pressure-sensitive adhesive composition containing an ester polymer and an amine compound is excellent in flame retardancy, excellent in tackiness and transparency, and hardly deteriorates in adhesive properties over time. I understood.

Claims (7)

A (meth) acrylic acid ester-based polymer comprising a repeating unit composed of a (meth) acrylic acid ester having a phosphoric acid ester group and a repeating unit composed of a (meth) acrylic acid ester having an alkyl group having 1 to 18 carbon atoms. Coalescence,
An amine compound,
A pressure-sensitive adhesive composition comprising: 2. The mixture according to claim 1, wherein the total amount of the amine compound is 0.1 to 50 parts by mass with respect to 100 parts by mass of the (meth) acrylic acid ester polymer. Pressure-sensitive adhesive composition. The pressure-sensitive adhesive composition according to claim 1 or 2, wherein the repeating unit composed of (meth) acrylic acid ester having a phosphate group is represented by the following general formula (1).
(In General Formula (1), A is an alkylene group having 1 to 8 carbon atoms, R ₁ is H or CH ₃ , and R ₂ and R ₃ are each independently H, C _n H _{2n + 1} (n = 1 To 8), or a group represented by C ₆ H _m (CH ₃ ) _5-m (m = 0 to 5). The pressure-sensitive adhesive according to any one of claims 1 to 3, wherein the amine compound is at least one of a secondary amine compound, a tertiary amine compound, an amidine compound, and a guanidine compound. Composition. The said (meth) acrylic-ester type polymer is that the ratio of the repeating unit which consists of the (meth) acrylic acid ester which has the said phosphate ester group is 10-50 mol%, The characterized by the above-mentioned. The pressure-sensitive adhesive composition according to any one of the above. The pressure sensitive adhesive layer which consists of a crosslinked material of the pressure sensitive adhesive composition as described in any one of Claims 1-5. A pressure-sensitive adhesive laminate comprising the pressure-sensitive adhesive layer according to claim 6 on at least one side of a substrate.