JP2002338906A - Flame-retardant pressure-sensitive adhesive tape and method for manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a flame-retardant pressure-sensitive adhesive tape which is excellent in basic adhesion characteristics such as tack and maintenance and has a high flame retardancy, and to provide a method for manufacturing the same. SOLUTION: In a flame-retardant pressure-sensitive adhesive tape formed by coating a substrate with a solventless photo-curable pressure-sensitive adhesive, which is prepared by adding a flame-retardant to a photo-curable pressure- sensitive adhesive primarily comprising at least an alkyl (meth) acrylate ester monomer, a monomer containing a polar group, an acrylic polymeric mass having a photo-active functional group and a photopolymerization initiator, 5-100 pts.wt. of phosphazene, 10-200 pts. wt. of hydrated alumina and 5-100 pts.wt. of ammonium polyphosphate are mixed as the flame-retardant with 100 pts.wt. of the photo-curable pressure-sensitive adhesive.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photocurable pressure-sensitive adhesive obtained by adding a flame retardant to an acrylic photocurable pressure-sensitive adhesive, and a method for producing the same. About.

[0002]

2. Description of the Related Art In recent years, in industries such as the electric and electronic fields,
Adhesives and pressure-sensitive adhesives used for joining parts are required to have high flame retardancy, high heat resistance, high adhesiveness, high reliability, etc. as products have higher performance, higher functionality, and more variety. Is growing. In particular, from the viewpoint of improving work efficiency and work environment, various components are often joined using a tape-like or sheet-like adhesive instead of a liquid adhesive.

[0003] In order to impart flame retardancy to this pressure-sensitive adhesive tape, it has conventionally been general to use a halogen-based flame retardant and antimony oxide in combination to make the adhesive tape flame-retardant. In some cases, toxic halogen-based gas may be generated in the human body at the time of combustion, or may cause corrosion of equipment and the like. Therefore, a flame-retarding method using no halogen-based flame retardant is urgently required.

As a flame retarding method not using a halogen-based flame retardant, it is known to incorporate a hydrated metal compound such as magnesium hydroxide or aluminum hydroxide.
In order to obtain a high flame-retardant effect, a large amount must be blended in the pressure-sensitive adhesive, which causes a problem that the pressure-sensitive adhesive properties are impaired.

Further, Japanese Patent Application Laid-Open No. 8-193187 proposes an adhesive tape using a mixture of a nitrogen-containing phosphorus compound such as ammonium polyphosphate and red phosphorus as a flame retardant.

[0006]

However, the pressure-sensitive adhesive tape described in JP-A-8-193187 has a problem that phosphine gas is generated because red phosphorus is used as a flame retardant.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems. By using phosphazene as a flame retardant, there is no generation of phosphine gas, and an acrylic high molecular weight having a photoactive functional group. Found that by using the body as a base polymer, a flame-retardant adhesive tape having good adhesive properties can be obtained,
This has led to the present invention.

[0008]

In order to achieve the object of the present invention, the present invention is configured as described in the appended claims.

That is, the present invention provides at least (meth)
A flame-retardant is used in a photocurable pressure-sensitive adhesive mainly containing an acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic high molecular weight substance having a photoactive functional group, and a photopolymerization initiator. In a flame-retardant pressure-sensitive adhesive tape obtained by coating the added solvent-free type photocurable pressure-sensitive adhesive on a substrate, phosphazene is used as a flame retardant in an amount of 5 to 100 parts by weight based on 100 parts by weight of the photocurable pressure-sensitive adhesive. Mix by weight.

Further, the present invention mainly comprises at least an alkyl (meth) acrylate monomer, a polar group-containing monomer, an acrylic high molecular weight material having a photoactive functional group, and a photopolymerization initiator. In a flame-retardant pressure-sensitive adhesive tape obtained by coating a solvent-free type photocurable pressure-sensitive adhesive with a flame retardant added to a photocurable pressure-sensitive adhesive as a component, 100 parts by weight of the photocurable pressure-sensitive adhesive On the other hand, as the flame retardant, 5 to 100 parts by weight of phosphazene and 10 to 200 parts by weight of hydrated alumina are blended.

[0011] Further, a light having at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator as main components. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free light-curable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the light-curable pressure-sensitive adhesive, Phosphazene is used as the flame retardant in an amount of 5 to 10
0 parts by weight and 5 to 100 parts by weight of ammonium polyphosphate are blended.

[0012] Further, a light mainly comprising at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free light-curable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the light-curable pressure-sensitive adhesive, Phosphazene is used as the flame retardant in 5 to 10
0 parts by weight, 10 to 200 parts by weight of hydrated alumina and 5 to 100 parts by weight of ammonium polyphosphate are blended.

In these cases, the oxygen index is set to 23 or more.

Further, in the method for producing a flame-retardant pressure-sensitive adhesive tape, a photo-curable film formed by applying the solvent-free photo-curable pressure-sensitive adhesive containing the flame retardant on a substrate to a thickness of 5 to 500 μm. When curing the adhesive layer, under an inert gas atmosphere,
Alternatively, the photocurable pressure-sensitive adhesive layer is cured by light irradiation while covering the transparent protective film from above.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The flame-retardant pressure-sensitive adhesive tape of the present invention comprises at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, and an acrylic polymer having a photoactive functional group. Phosphazene 5 to 10 with respect to 100 parts by weight of a photocurable pressure-sensitive adhesive containing a photopolymerization initiator as a main component.
0 parts by weight, or 5 to 100 parts by weight of phosphazene and 10 to 200 parts by weight of hydrated alumina, or 5 to 100 parts by weight of phosphazene and 5 to 100 parts of ammonium polyphosphate
5 to 100 parts by weight of phosphazene, 10 to 200 parts by weight of hydrated alumina and 5 to 100 parts by weight of ammonium polyphosphate are applied to the substrate with a solvent-free photocurable pressure-sensitive adhesive. It does not generate toxic halogen-based gas or phosphine gas during combustion,
Moreover, it does not contain antimony which has an adverse effect on the human body, is excellent in basic adhesive properties such as adhesive strength and holding power, and has flame retardancy.

The phosphazenes used here are, specifically, trade names SA-100 and SPR-1 manufactured by Otsuka Chemical Co., Ltd.
00, NF-46, NF-68, NF-100 and the like.

Phosphazene decomposes during combustion to produce phosphoric acid or polyphosphoric acid, which further forms a carbonized layer film and develops flame retardancy by shielding the tape from heat and oxygen.

The hydrated alumina used in combination here is:
Although not particularly limited, the specific surface area is 5 m ² / g or less, and the average particle diameter is 3 μm or more and 25 μm or less. Use of hydrated alumina having an average particle size outside this range affects the processability, sedimentation, and the like of the pressure-sensitive adhesive. Specifically, trade names HX, H-21, H-3 manufactured by Showa Denko KK
1, H-32, H-42, H-42M, H-43, H-
43M, H-100, H-210, H-310, H-3
20, H-32ST, H-320ST, H-42ST
E, H-42STV, H-32T, H-34, H-34
HL, H-10CX, H-31I, H-32I, H-3
2S, H-42S and the like.

Hydrated alumina causes dehydration endothermic reaction at around 300 ° C. in crystallization water, and exhibits flame retardancy.

The ammonium polyphosphate used here is Sumisafe P manufactured by Sumitomo Chemical Co., Ltd., Exolit 422, Exolit 462, H
ostflamTPAP745, Terage C60, C70, and C80 manufactured by Chisso Corporation.

The above-mentioned ammonium polyphosphate acts as a foaming agent at the time of combustion, and at the time of combustion, a heat-insulating foam layer is formed.
The flame retardancy is exhibited by lowering the temperature inside the surface layer of the molded product.

In general, when the amount of the flame retardant is too large, the adhesive strength is reduced. When the amount is too small, the effect of the flame retardancy is reduced, and the flame retardant properties in the standard may not be satisfied. That is, if the compounding amount of the flame retardant with respect to 100 parts by weight of the photocurable pressure-sensitive adhesive exceeds 100 parts by weight for phosphazene, 200 parts by weight for hydrated alumina, and 100 parts by weight for ammonium polyphosphate, There is a risk of lowering the power. Also, if the compounding amount of the flame retardant per 100 parts by weight of the photocurable pressure-sensitive adhesive is less than 5 parts by weight for phosphazene, 10 parts by weight for hydrated alumina, and less than 5 parts by weight for ammonium polyphosphate, There is a possibility that the effect of the flame retardancy is reduced and the flame retardant characteristics in the standard are not satisfied.

The acrylic high molecular weight compound having a photoactive functional group used in the present invention is used for improving workability such as coating property. The acrylic high molecular weight product has a weight average molecular weight of 200,000 to 3,000,000 and a photoactive functional group content of 0.01 to 2.0 meq /
What is g is good.

As a method for introducing the photoactive functional group into the acrylic high molecular weight compound, an isocyanate compound having a (meth) acryloyloxy group in the side chain of the acrylic high molecular weight compound (for example, -Methacryloyloxyethyl isocyanate). In this way, an acrylic high molecular weight substance having a photoactive functional group such as a (meth) acryloyloxy group can be obtained. However, the introduction method is not particularly limited. This acrylic high molecular weight substance is used by dissolving in an acrylic monomer or the like.

When the weight average molecular weight of the above-mentioned acrylic high molecular weight compound having a photoactive functional group is less than 200,000,
In consideration of coatability and the like, it is difficult to obtain a high-viscosity adhesive composition of several thousands to tens of thousands cP, which is not preferable. When the weight average molecular weight is more than 3,000,000, there is no particular problem in the properties of the pressure-sensitive adhesive tape, but it is difficult to mass-produce an acrylic high molecular weight substance, which is not preferable.

The composition of the acrylic high molecular weight compound having a photoactive functional group in the pressure-sensitive adhesive composition is adjusted according to the target pressure-sensitive adhesive properties and the viscosity at the time of coating.
It is used at 5 to 50% by weight in the adhesive composition. The main component of the acrylic high molecular weight substance having a photoactive functional group is usually a copolymer of a (meth) acrylic acid alkyl ester monomer and a polar group-containing monomer, for example, 2-ethylhexyl acrylate and acryl A copolymer with an acid, a copolymer of isooctyl acrylate and 2-hydroxyethyl methacrylate, a terpolymer of 2-ethylhexyl acrylate, acrylic acid and 2-hydroxyethyl methacrylate, and the like are used. However, the present invention is not particularly limited to these.

The above-mentioned alkyl (meth) acrylate monomer includes, for example, ethyl group, propyl group,
A butyl group, pentyl group, hexyl group, 2-ethylhexyl group, octyl group, isooctyl group, nonyl group, isononyl group, decyl group, etc.
Examples of (meth) acrylic acid esters having the following alkyl groups include: The above-mentioned alkyl (meth) acrylate is used alone or in combination of two or more.

The above polar group-containing monomers include acrylic acid, methacrylic acid, itaconic acid, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, dimethylaminoethyl acrylate, acrylonitrile, methacrylonitrile , N-vinyl-2-pyrrolidone and the like, and a polymerizable unsaturated monomer having a polar group such as a carboxyl group, a hydroxyl group and an amino group in the molecule.

The compounding amount of the polar group-containing monomer is from the above-mentioned alkyl (meth) acrylate 99 to 70.
It is preferably from 1 to 30% by weight based on the weight%. When the amount of the polar group-containing monomer is less than 1% by weight, the adhesive strength of the pressure-sensitive adhesive tape is reduced. When the amount of the polar group-containing monomer is more than 30% by weight, the adhesive force of the adhesive tape is low. In any case, which is not preferred. In addition,
The polar group-containing monomers described above are used alone or in combination of two or more.

The photopolymerization initiator used in the present invention is, for example, a general photopolymerization initiator used for radical photopolymerization such as a vinyl group or a (meth) acryloyloxy group, or a curing agent for an ultraviolet curable resin. The radical photopolymerization initiator used can be used. For example, compounds such as benzoin, benzoin methyl ether, benzoin ethyl ether, trichloroacetophenone, benzophenone, and benzyl can be used.

The following photopolymerization initiators sold by Ciba Specialty Chemicals can also be used. For example, benzyldimethyl ketal compounds such as 2,2-dimethoxy-1,2-diphenylethan-1-one (Irgacure 651 from Ciba Specialty Chemicals), 1-hydroxycyclohexylphenyl ketone (Ciba Specialty Chemicals) Irgacure 184), 2-hydroxy-2-methyl-1
Α-hydroxyketone compounds such as -phenylpropan-1-one (Darocur 1173 of Ciba Specialty Chemicals), 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) butanone-1
Α-aminoketone compounds such as (Irgacure 369 of Ciba Specialty Chemicals), bis (2,
Bisacylphosphine oxide compounds such as 4,6-trimethylbenzoyl) phenylphosphine oxide (Irgacure 819 of Ciba Specialty Chemicals), bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl 1: 3 mixture of bisacylphosphine oxide such as phosphine oxide and Darocure 1173 (Irgacure 1700 from Ciba Specialty Chemicals), bis (2,6-dimethoxybenzoyl) -2,4,4-trimethylpentyl phos A 1: 1 mixture of a bisacylphosphine oxide such as finoxide and Irgacure 184 (Irgacure 1850 from Ciba Specialty Chemicals), benzoin ethyl ether,
Benzoin ether compounds such as benzoin isopropyl ether are exemplified. In particular, a photopolymerization initiator such as a bisacylphosphine oxide-based compound that generates two or more active species (radicals) from one molecule of the photopolymerization initiator by light irradiation is preferable.

These photopolymerization initiators are preferably used in a proportion of 0.01 to 5 parts by weight based on 100 parts by weight of the acrylic high molecular weight compound having a photoactive functional group. When the amount is less than 0.01 part by weight, it is difficult to complete the photocuring reaction sufficiently. When the amount is more than 5 parts by weight, the molecular weight of the obtained pressure-sensitive adhesive polymer is low. In any case, it is not preferable in terms of the properties of the pressure-sensitive adhesive tape.

The polyfunctional photopolymerizable compound used as a cross-linking agent in the pressure-sensitive adhesive composed of the acrylic polymer having a photoactive functional group is 100% by weight of the acrylic polymer having a photoactive functional group. To 0.01 parts
About 5 parts by weight of a photopolymerizable compound such as a polyfunctional (meth) acrylic monomer is preferred. Such polyfunctional photopolymerizable compounds include hexanediol (meth) acrylate, neopentyl di (meth) acrylate, pentaerythritol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate And polyethylene glycol di (meth) acrylate, polypropylene glycol di (meth) acrylate, epoxy acrylate oligomer, polyester acrylate oligomer, urethane acrylate oligomer, and the like.

It is desirable that the flame retardant pressure-sensitive adhesive tape of the present invention has an oxygen index of 23 or more, preferably 25 or more, which is an index of flame retardancy. If the oxygen index is less than 23, it may become flammable and the self-extinguishing property may be lost.

The method for producing a flame-retardant pressure-sensitive adhesive tape of the present invention comprises the steps of: providing a solvent-free photocurable pressure-sensitive adhesive containing a flame retardant on a substrate;
When the photocurable pressure-sensitive adhesive layer formed by coating to a thickness of about 500 μm is cured, the light-curable pressure-sensitive adhesive layer is irradiated with light under an inert gas atmosphere or while covering with a transparent protective film from above. Therefore, it is possible to prevent the surface effect of the pressure-sensitive adhesive layer from being hindered by oxygen in the air. In particular, when covering with a transparent protective film, volatilization of the monomer due to heat generation during curing is prevented, and the film thickness of the flame-retardant pressure-sensitive adhesive tape is made uniform.

In this case, it is desirable that the coating thickness of the adhesive is 5 μm or more, preferably 50 μm or more. If the coating thickness of the pressure-sensitive adhesive is less than 5 μm, the particle diameter becomes smaller than the particle diameter of the flame retardant, and a flame-retardant pressure-sensitive adhesive tape cannot be obtained, which is not preferable. Further, when the coating thickness of the adhesive is 500 μm or more,
It is not preferable because bubbles are mixed in the tape.

The flame-retardant pressure-sensitive adhesive tape of the present invention is widely used for applications requiring flame retardancy. In particular, it is suitably used for various electronic parts which are easily affected by halogen gas. They are bonded to form electronic components. Such electronic components are not particularly limited, and include, for example, interlayer insulation of a transformer and lamination of an electromagnetic shielding film.

[0038]

EXAMPLES The flame-retardant pressure-sensitive adhesive tape of the present invention and the method for producing the same will be specifically described with reference to examples. However, the flame-retardant pressure-sensitive adhesive tape of the present invention and the method for producing the same are not limited thereto. In the description of Examples and Specific Examples of the present invention, "parts" indicates parts by weight.

Example 1 Acrylic acid copolymer 27.5
Part, 60 parts of 2-ethylhexyl acrylate, 12.5 parts of acrylic acid, 5 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., Ltd., trade name: SPR-100), and two double bonds in the molecule. A pressure-sensitive adhesive obtained by adding 0.05 parts of the reactive monomer (hexanediol acrylate) having the above and 0.3 parts of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) and uniformly mixing the resulting mixture with a polyester 50 thickness on film (50μm thickness)
It was applied so as to have a thickness of 0 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 2 Acrylic acid copolymer 27.5
Parts, 2-ethylhexyl acrylate 60 parts, and acrylic acid 12.5 parts in an adhesive composition, 100 parts of propoxyphosphazene (trade name: SPR-100, manufactured by Otsuka Chemical Co., Ltd.)
And 0.05 parts of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) are added. Was coated on a polyester film (50 μm thick) so as to have a thickness of 500 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. . As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 3 28 parts of acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 20 parts of propoxyphosphazene (trade name: SPR-100, manufactured by Otsuka Chemical Co., Ltd.), 50 parts of hydrated alumina (trade name: H-21, manufactured by Showa Denko KK) 0.01 part of a reactive monomer having two or more heavy bonds (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) were added and uniformly mixed. Adhesive, 70μ thick polyester film (50μm thick)
m, and a transparent protective film was overlaid thereon and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 4 28 parts of acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 20 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 100 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), two parts in the molecule 0.01 part of a reactive monomer having two or more heavy bonds (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) were added and uniformly mixed. An adhesive is applied to a polyester film (50 μm thick) with a thickness of 70
μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 5 28 parts of acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 20 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 200 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), and two parts in the molecule. 0.01 part of a reactive monomer having two or more heavy bonds (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) were added and uniformly mixed. An adhesive is applied to a polyester film (50 μm thick) with a thickness of 70
μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 6 28 parts of acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 100 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 200 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21),
0.01 part of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) are added and mixed uniformly. The pressure-sensitive adhesive obtained as described above is applied to a polyester film (50 μm thick) with a thickness of 5 μm.
It was applied so as to have a thickness of 00 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 7 28 parts of acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 20 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 10 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), and two parts in the molecule. 0.01 part of a reactive monomer having two or more heavy bonds (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) were added and uniformly mixed. An adhesive is applied to a polyester film (50 μm thick) with a thickness of 500
μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 8 28 parts of acrylic acid copolymer
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Parts of the adhesive composition, 20 parts of propoxyphosphazene (trade name: SPR-100, manufactured by Otsuka Chemical Co., Ltd.), 50 parts of hydrated alumina (trade name: H-21, manufactured by Showa Denko KK) 0.01 part of a reactive monomer having two or more heavy bonds (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) were added and uniformly mixed. Adhesive, 5μm thick polyester film (50μm thick)
, A transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 9 28 parts of an acrylic acid copolymer,
62 parts of 2-ethylhexyl acrylate, 10 of acrylic acid
Part of the adhesive composition, 20 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., Ltd., trade name: SPR-100) and ammonium polyphosphate (manufactured by Sumitomo Chemical Co., trade name: Sumisafe P)
Of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals). , A pressure-sensitive adhesive obtained by mixing uniformly, a polyester film (50 μm thick)
Was coated so as to have a thickness of 500 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and self-extinguishing properties.

Example 10 Acrylic acid copolymer 28
Parts, 62 parts of 2-ethylhexyl acrylate, 10 parts of acrylic acid, 20 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), and ammonium polyphosphate (manufactured by Sumitomo Chemical Co., trade name) : 100 parts of Sumisafe P) and 0.1 part of a reactive monomer (hexanediol acrylate) having two or more double bonds in the molecule.
And 0.1 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) and uniformly mixed.
(thickness: μm) so as to have a thickness of 70 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 11 Acrylic acid copolymer 28
Parts, 62 parts of 2-ethylhexyl acrylate, 10 parts of acrylic acid, 100 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), and ammonium polyphosphate (manufactured by Sumitomo Chemical Co., trade name) : Sumisafe P), 100 parts of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate), 0.01 part and photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) 0.3 Add the parts
The adhesive obtained by uniform mixing is applied to a polyester film (50 μm thick) so as to have a thickness of 70 μm, a transparent protective film is overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. Was. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 12 Acrylic acid copolymer 28
Part, 2-ethylhexyl acrylate 62 parts, acrylic acid 10 parts, a propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 20 parts, hydrated alumina (manufactured by Showa Denko KK, trade name) : 50 parts of H-21),
10 parts of ammonium polyphosphate (trade name: Sumisafe P, manufactured by Sumitomo Chemical Co., Ltd.), 0.01 part of a reactive monomer (hexanediol acrylate) having two or more double bonds in a molecule, and Irgacure 819 photopolymerization initiator (Ciba Specialty Chemicals) Add 0.3 parts,
The adhesive obtained by uniform mixing is applied to a polyester film (50 μm thick) so as to have a thickness of 70 μm, a transparent protective film is overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. Was. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 13 Acrylic acid copolymer 28
Part, 2-ethylhexyl acrylate 62 parts, acrylic acid 10 parts, 20 parts propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), hydrated alumina (manufactured by Showa Denko KK, trade name) : H-21) is 100
Part, ammonium polyphosphate (Sumitomo Chemical Co., trade name:
10 parts of Sumisafe P), 0.01 part of a reactive monomer (hexanediol acrylate) having two or more double bonds in the molecule, and Irgacure 819 photopolymerization initiator.
(Ciba Specialty Chemicals Co.) Add 0.3 part, uniformly mix and apply the resulting adhesive to a polyester film (50 μm thick) to a thickness of 70 μm, and place a transparent protective coating on it. Overlay the film, irradiate light,
A flame-retardant adhesive tape was obtained. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 14 Acrylic acid copolymer 28
Part, 2-ethylhexyl acrylate 62 parts, acrylic acid 10 parts, a propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 20 parts, hydrated alumina (manufactured by Showa Denko KK, trade name) : 10 parts of H-21),
100 parts of ammonium polyphosphate (manufactured by Sumitomo Chemical Co., Ltd., trade name: Sumisafe P), a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate)
To the polyester film (50 μm thick) to a thickness of 70 μm, and the resulting mixture was uniformly mixed with 0.01 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) and 0.3 part of a photopolymerization initiator. And apply
A transparent protective film was overlaid thereon and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent adhesive basic properties and flame retardancy.

Example 15 Acrylic acid copolymer 28
Part, 62 parts of 2-ethylhexyl acrylate, 10 parts of acrylic acid, 100 parts of propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), and hydrated alumina (manufactured by Showa Denko KK, trade name) : H-21) is 200
Part, ammonium polyphosphate (Sumitomo Chemical Co., trade name:
100 parts of Sumisafe P), 0.01 part of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate), and Irgacure 819 photopolymerization initiator
(Ciba Specialty Chemicals) 0.3 part is added, and the pressure-sensitive adhesive obtained by mixing uniformly is applied to a polyester film (50 μm thick) to a thickness of 500 μm, and a transparent protective film is applied thereon. Overlay the film, irradiate light,
A flame-retardant adhesive tape was obtained. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Example 16 Acrylic acid copolymer 28
Part, 2-ethylhexyl acrylate 62 parts, acrylic acid 10 parts, a propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), 20 parts, hydrated alumina (manufactured by Showa Denko KK, trade name) : H-21) is 200
Part, ammonium polyphosphate (Sumitomo Chemical Co., trade name:
Reactive monomer (hexanediol acrylate) having 5 parts of Sumisafe P) and two or more double bonds in the molecule
To the polyester film (50 μm thick) to a thickness of 70 μm, and the resulting mixture was uniformly mixed with 0.01 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) and 0.3 part of a photopolymerization initiator. And apply
A transparent protective film was overlaid thereon and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this flame-retardant pressure-sensitive adhesive tape had excellent adhesive basic properties and flame retardancy.

Example 17 Acrylic acid copolymer 28
Part, 2-ethylhexyl acrylate 62 parts, acrylic acid 10 parts, 20 parts propoxyphosphazene (manufactured by Otsuka Chemical Co., trade name: SPR-100), hydrated alumina (manufactured by Showa Denko KK, trade name) : H-21) is 200
Part, ammonium polyphosphate (Sumitomo Chemical Co., trade name:
10 parts of Sumisafe P), 0.01 part of a reactive monomer (hexanediol acrylate) having two or more double bonds in the molecule, and Irgacure 819 photopolymerization initiator.
(Ciba Specialty Chemicals Co.) Add 0.3 part, uniformly mix and apply the resulting adhesive to a polyester film (50 μm thick) to a thickness of 70 μm, and place a transparent protective coating on it. Overlay the film, irradiate light,
A flame-retardant adhesive tape was obtained. As shown in Table 1, this flame retardant pressure-sensitive adhesive tape had excellent basic adhesive properties and flame retardancy.

Comparative Example 1 Acrylic acid copolymer 27.5
Part, 2-ethylhexyl acrylate 60 parts, acrylic acid 12.5 parts, 0.05 part of a reactive monomer (hexanediol acrylate) having two or more double bonds in the molecule, and a photopolymerization initiator Irgacure 819
(Ciba Specialty Chemicals Co.) Add 0.3 part, uniformly mix and apply the resulting adhesive to a polyester film (50 μm thick) to a thickness of 70 μm, and place a transparent protective coating on it. Overlay the film, irradiate light,
An adhesive tape was obtained. As shown in Table 1, this adhesive tape was inferior in flame retardancy.

Comparative Example 2 Acrylic acid copolymer 27.5
Part, 2-ethylhexyl acrylate 60 parts, acrylic acid 12.5 parts, 100 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), and two double bonds in the molecule. 0.05 parts of the reactive monomer (hexanediol acrylate) having the above and a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) 0.
The adhesive obtained by adding 3 parts and uniformly mixing is applied to a polyester film (50 μm thick) so as to have a thickness of 70 μm, a transparent protective film is superimposed thereon, and light irradiation is performed. A flammable adhesive tape was obtained. As shown in Table 1, this adhesive tape was inferior in flame retardancy.

Comparative Example 3 Acrylic Acid Copolymer 27.5
Part, 2-ethylhexyl acrylate 60 parts, 12.5 parts of acrylic acid, 100 parts of ammonium polyphosphate (Sumitomo Chemical Co., Ltd., trade name: Sumisafe P), and two or more double bonds in the molecule. 0.05 parts of a reactive monomer (hexanediol acrylate) and 0.3 parts of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) are added and uniformly mixed to obtain a pressure-sensitive adhesive. 70μ thick on film (50μm thick)
m, and a transparent protective film was overlaid thereon and irradiated with light to obtain a flame-retardant adhesive tape. This adhesive tape had self-extinguishing properties as shown in Table 1.

Comparative Example 4 Acrylic Acid Copolymer 27.5
Part, 2-ethylhexyl acrylate 60 parts, acrylic acid 12.5 parts, adhesive composition 50 parts hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), ammonium polyphosphate (manufactured by Sumitomo Chemical Co., Ltd.) Product name: Sumisafe P) 50
And 0.05 parts of a reactive monomer having two or more double bonds in the molecule (hexanediol acrylate) and 0.3 part of a photopolymerization initiator Irgacure 819 (Ciba Specialty Chemicals) are added. Was applied to a polyester film (50 μm thick) so as to have a thickness of 70 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. .
This adhesive tape had self-extinguishing properties as shown in Table 1.

Comparative Example 5 Acrylic acid copolymer 27.5
Parts, 2-ethylhexyl acrylate 60 parts, acrylic acid 12.5 parts, an adhesive composition, 50 parts of hydrated alumina (manufactured by Showa Denko KK, trade name: H-21), and aromatic condensed phosphoric acid ester (Dahachi) 50 parts of Chemical Industry Co., Ltd., trade name: PX-200), 0.05 parts of a reactive monomer (hexanediol acrylate) having two or more double bonds in the molecule, and a photopolymerization initiator Irgacure 819 (Ciba. (Specialty Chemicals Co., Ltd.) 0.3 part was added, and the pressure-sensitive adhesive obtained by mixing uniformly was mixed with a polyester film (50 μm thick).
Was coated so as to have a thickness of 70 μm, a transparent protective film was overlaid thereon, and irradiated with light to obtain a flame-retardant adhesive tape. As shown in Table 1, this adhesive tape was inferior in flame retardancy.

Various properties of the obtained flame-retardant pressure-sensitive adhesive tape were measured by the following methods, and the results are shown in Table 1.

[0062]

[Table 1] [Adhesive force] According to the method of JIS Z 0237-1991, the adhesive surface of the flame-retardant adhesive tape test piece was slightly adhered to a stainless steel plate to be adhered, and a load of 2 kg was applied from above the test piece via a polyester film. With a roller of
Twenty minutes after the adhesive tape was bonded, the adhesive tape was peeled off by 180 ° at a peeling speed of 300 mm / min using an Aiko tensile tester to measure the adhesive strength.

[Holding force] According to the method of JIS Z 0237, the adhesive surface of the flame-retardant adhesive tape test piece was attached to a stainless steel plate to be adhered such that an area of 25 mm × 25 mm was in contact with the stainless steel plate. Through the top 5
After pressing with a kg roller and leaving for 72 hours, 1
After applying a load of kg and standing at 80 ° C. for 24 hours, those that did not fall were rated as ○, and those that fell were rated as x.

[Oxygen Index] In a mixed gas of oxygen and nitrogen which gradually rises, the oxygen concentration can be reduced under the condition that the material keeps burning like a candle flame, and it can barely keep burning. The oxygen concentration is called the limiting oxygen index. By measuring this, the flammability of the polymer material can be measured. As a measure of flammability, those with an oxygen index of 22 or less are considered to be flammable, those with an oxygen index of 23 to 27 are self-extinguishing, and those with an oxygen index of 28 or more are flame-retardant. Are said to have flame retardancy. The oxygen index was measured according to JIS K7201.
Method.

[0065]

As described above, the present invention relates to an alkyl (meth) acrylate monomer, a polar group-containing monomer, an acrylic high molecular weight material having a photoactive functional group, In a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photocurable pressure-sensitive adhesive with a flame retardant added to a photocurable pressure-sensitive adhesive containing a polymerization initiator as a main component, Since 5 to 100 parts by weight of the phosphazene is blended as the flame retardant with respect to 100 parts by weight of the adhesive, a flame-retardant adhesive tape excellent in basic adhesive properties and flame retardancy can be obtained.

Further, the present invention comprises a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator as main components. In the photo-curable pressure-sensitive adhesive to be used, in a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photo-curable pressure-sensitive adhesive to which a flame retardant is added, on the base material, On the other hand, phosphazene is used as the flame retardant in an amount of 5 to 10
Since 0 parts by weight and 10 to 200 parts by weight of hydrated alumina are blended, a flame-retardant pressure-sensitive adhesive tape excellent in basic adhesive properties and flame retardancy can be obtained.

Further, the present invention comprises a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator. In the photo-curable pressure-sensitive adhesive to be used, in a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photo-curable pressure-sensitive adhesive to which a flame retardant is added, on the base material, On the other hand, phosphazene is used as the flame retardant in an amount of 5 to 10
Since 0 parts by weight and 5 to 100 parts by weight of ammonium polyphosphate are blended, a flame-retardant pressure-sensitive adhesive tape having excellent basic adhesive properties and flame retardancy can be obtained.

Further, the present invention comprises a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator as main components. In the photo-curable pressure-sensitive adhesive to be used, in a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photo-curable pressure-sensitive adhesive to which a flame retardant is added, on the base material, On the other hand, phosphazene is used as the flame retardant in an amount of 5 to 10
0 parts by weight, 10 to 200 parts by weight of hydrated alumina and 5 to 100 parts by weight of ammonium polyphosphate to obtain excellent adhesive basic properties and flame-retardant adhesive tape with more excellent flame retardancy. Can be.

In these cases, since the oxygen index is 23 or more, a flame-retardant pressure-sensitive adhesive tape excellent in flame retardancy can be obtained. Further, in the method for producing a flame-retardant pressure-sensitive adhesive tape, a photocurable pressure-sensitive adhesive layer formed by applying the solvent-free photocurable pressure-sensitive adhesive containing the flame-retardant on a substrate to a thickness of 5 to 500 μm. When curing, under an inert gas atmosphere,
Alternatively, since the photocurable pressure-sensitive adhesive layer is cured by light irradiation while being covered with a transparent protective film from above, the surface effect of the pressure-sensitive adhesive layer due to oxygen in the air can be prevented from being hindered. In particular, when covering with a transparent protective film, volatilization of the monomer due to heat generation during curing is prevented, and the film thickness of the flame-retardant pressure-sensitive adhesive tape is made uniform.

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kazuo Naume 3819 Notobe, Tama-ku, Kawasaki-shi, Kanagawa F-Term in Sliontec Co., Ltd. (reference) 4J004 AA10 AA17 AA18 AB07 CA00 FA05 FA08 GA01 4J040 DF011 FA091 FA101 FA111 FA131 HA136 HB13 HB14 HB18 JB09 KA13 KA36 KA42 LA08 NA19

Claims (6)

[Claims] 1. A light comprising at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic polymer having a photoactive functional group, and a photopolymerization initiator. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free light-curable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the light-curable pressure-sensitive adhesive, A flame-retardant pressure-sensitive adhesive tape, comprising 5 to 100 parts by weight of phosphazene as the flame retardant. 2. A light containing at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic high molecular weight substance having a photoactive functional group, and a photopolymerization initiator. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free type photocurable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the photocurable pressure-sensitive adhesive, A flame-retardant pressure-sensitive adhesive tape, comprising 5 to 100 parts by weight of phosphazene and 10 to 200 parts by weight of hydrated alumina as the flame retardant. 3. A light containing at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic high molecular weight substance having a photoactive functional group, and a photopolymerization initiator. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free light-curable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the light-curable pressure-sensitive adhesive, A flame-retardant pressure-sensitive adhesive tape, comprising 5 to 100 parts by weight of phosphazene and 5 to 100 parts by weight of ammonium polyphosphate as the flame retardant. 4. A light comprising at least a (meth) acrylic acid alkyl ester monomer, a polar group-containing monomer, an acrylic high molecular weight material having a photoactive functional group, and a photopolymerization initiator. In a curable pressure-sensitive adhesive, a flame-retardant pressure-sensitive adhesive tape obtained by applying a solvent-free light-curable pressure-sensitive adhesive to which a flame retardant has been added, on the basis of 100 parts by weight of the light-curable pressure-sensitive adhesive, A flame-retardant pressure-sensitive adhesive tape, comprising 5 to 100 parts by weight of phosphazene, 10 to 200 parts by weight of hydrated alumina and 5 to 100 parts by weight of ammonium polyphosphate as the flame retardant. 5. The flame-retardant pressure-sensitive adhesive tape according to claim 1, wherein the oxygen index is 23 or more. 6. A method according to claim 1, wherein the solvent-free photo-curable pressure-sensitive adhesive containing the flame retardant according to claim 1 is applied to a substrate.
When the photocurable pressure-sensitive adhesive layer formed by coating to a thickness of about 500 μm is cured, the light-curable pressure-sensitive adhesive layer is irradiated with light under an inert gas atmosphere or while covering with a transparent protective film from above. A method for producing a flame-retardant pressure-sensitive adhesive tape, characterized by being produced by curing with an adhesive.