JP2010265345A - Pressure-sensitive adhesive sheet and laminate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure-sensitive adhesive sheet and a laminate conforming to VTM-0 rating in a test according to UL94 standards although the pressure-sensitive adhesive itself does not contain a flame retardant. <P>SOLUTION: The pressure-sensitive adhesive sheet comprises a substrate and a nonflame-retardant pressure-sensitive adhesive formed on the substrate, wherein the substrate conforms to VTM-0 rating in a test according to UL94 standards, the total thickness of the substrate and the pressure-sensitive adhesive is 35 to 200 μm, and the thickness ratio of the substrate to the pressure-sensitive adhesive ranges from 1:1 to 8:1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a pressure-sensitive adhesive sheet and a laminate, and particularly to a flame-retardant pressure-sensitive adhesive sheet and a laminate.

  Conventionally, a pressure-sensitive adhesive sheet in which a pressure-sensitive adhesive is applied to a film or paper is poor in flame retardancy. For example, in order to impart flame retardancy, for example, an acrylic polymer having an ionic crosslinking structure and water are added to the pressure-sensitive adhesive. It is known to use a composition containing aluminum oxide (see Patent Document 1).

JP 2002-322447 A (Claim 1 etc.)

  However, unless these flame retardants are added and mixed in a large amount, a sufficient flame retardant effect, for example, a flame retardant property conforming to VTM-0 cannot be obtained in a test according to the UL94 standard. In addition, these flame retardants are added and mixed in large quantities, so that the pressure-sensitive adhesive is plasticized and deposited on the pressure-sensitive adhesive sheet surface or the interface with the adherend, thereby causing contamination or deterioration of the adherend. There was a problem of promoting.

  In view of such circumstances, an object of the present invention is to provide a pressure-sensitive adhesive sheet that exhibits sufficient flame retardancy with a simple configuration, and a laminate using the pressure-sensitive adhesive sheet.

  The pressure-sensitive adhesive sheet of the present invention is a pressure-sensitive adhesive sheet comprising a base material and a non-flame retardant pressure-sensitive adhesive formed on the base material, and the base material is a test according to UL94 standard. VTM-0, the total thickness of the base material and the pressure sensitive adhesive is 35 to 200 μm, and the thickness ratio of the base material and the pressure sensitive adhesive is 1: 1 to 8 : 1.

  In the present invention, even if a non-flame retardant pressure-sensitive adhesive that does not contain a flame retardant in the pressure-sensitive adhesive is formed on a base material that conforms to VTM-0 in a test conforming to the UL94 standard with a single base material, Sufficient flame retardancy can be obtained by providing a flame-retardant adherend on the pressure-bonding sheet.

  The laminate of the present invention comprises the pressure-sensitive adhesive sheet, and is an adherend conforming to VTM-0 or V-0 in a test according to UL94 standard on the side opposite to the base material of the pressure-sensitive adhesive. Is provided. Even if the laminate of the present invention is a non-flame retardant pressure-sensitive adhesive that does not contain a flame retardant in the pressure-sensitive adhesive, the adherend conforming to VTM-0 or V-0 and the UL94 standard in a test according to the UL94 standard. By providing a base material conforming to VTM-0 in the test according to the above, sufficient flame retardancy can be obtained as a whole.

  Preferably, as a sufficient flame retardancy, it is mentioned that this laminate conforms to VTM-0 in a test according to the UL94 standard.

  In the pressure-sensitive adhesive sheet and laminate of the present invention, even if a non-flame retardant pressure-sensitive adhesive is used, a base material conforming to VTM-0 is provided in a test according to the UL94 standard. By providing it on an adherend that conforms to VTM-0 in a test according to the above, there is an excellent effect that sufficient flame retardancy can be obtained. In the pressure-sensitive adhesive sheet and laminate of the present invention, since no flame retardant is added to the pressure-sensitive adhesive, the pressure-sensitive adhesive is plasticized and deposited on the pressure-sensitive adhesive sheet surface and the adherend. As a result, there is an excellent effect that contamination and deterioration of the adherend are not promoted.

  Hereinafter, the pressure-sensitive adhesive sheet of the present invention will be described in detail by dividing it into (1) a substrate and (2) a pressure-sensitive adhesive. 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.

(1) Base material The base material of this invention has a flame retardance which adapts to VTM-0 in the test according to UL94 specification. As such a base material, a film made of a polyimide resin, a polyphenylene sulfide resin, a polyetherimide resin, a polyphenylene etherimide resin, a polyetheretherketone resin, or the like and having flame retardancy with a single resin can be used. In addition, a polycarbonate resin, a polystyrene resin, a polyethylene resin, a polyester resin, a polyolefin resin, a polyurethane resin, a phenol resin, a urea resin, an EVA resin, an acrylic resin, an acrylonitrile butadiene resin (ABS resin), an epoxy resin, containing a flame retardant described later. Examples include a flame retardant film made of a polystyrene-polycarbonate alloy resin, a polystyrene-ABS alloy resin, a polyamide resin, and the like.

  Moreover, it is good also as a base material which has a flame retardance by coating one of the above-mentioned resin on a base material. As the substrate in this case, for example, a sheet-like or film-like plastic, paper such as impregnated paper, metal foil, woven fabric, non-woven fabric, or the like may be used. Moreover, although the thickness of a base material is suitably determined according to the use of an adhesive sheet, it is about 10-300 micrometers normally, Preferably it is about 20-200 micrometers. In this embodiment, it is about 10-190 micrometers, Preferably it is about 20-180 micrometers, Most preferably, it is about 25-145 micrometers.

  Here, as the flame retardant, a halogen flame retardant, an inorganic flame retardant, or the like can be used. In particular, it is preferable to use an inorganic flame retardant from the viewpoint of environmental friendliness. Moreover, you may use in combination of 2 or more among the flame retardants mentioned below.

  Inorganic flame retardants include antimony trioxide, antimony pentoxide, zinc sulfide, zinc borate, molybdenum compound, tin compound, zirconium oxide, iron oxide, zinc oxide, carbon black, copper nitrate, iron nitrate, sulfonate metal salt, Phosphazene compounds, nanocomposite fillers, fumed silica, finely divided calcium carbonate, lithium carbonate, ferrocene, iron oxide, ferric hydroxide, activated ferrooxide, nickel oxide, aluminum / copper zeolite, copper thiocyanide, oxalic acid Copper, acetyl aluminum acetate, hydrated metal compounds, hydroquinoline metal salts (Fe, Mo, Co, V), phthalocyanine metal salts (Fe, Cu, Mn, Co, V), red phosphorus, ammonium phosphate, etc. Is mentioned.

  Halogen flame retardants include hexabromobenzene, bis (dibromopropyl) tetrabromobisphenol A, bis (dibromopropyl isocyanurate), tris (tribromoneopentyl phosphate, decabromodiphenyl oxide, brominated epoxy resin, bis (penta Bromophenoxy) triazine, ethylenebistetrabromophthalimide, polybromophenylindane, brominated polystyrene, tetrabromobisphenol A polycarbonate, brominated phenylene oxide, polypentabromobenzyl acrylate, chlorinated paraffin, chlorinated polyethylene, chlorendic anhydride , Cycloaliphatic chlorine compounds, brominated phenols, dibromometacresol, tris (chloroethyl) phosphate, tris (chloropropyl) phos Eto and the like.

  Other flame retardants include triphenyl phosphate, tricresyl phosphate, trixylyl phosphate, triethyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, cresyl bis (di-2,6-xylenyl) phosphate, 2 ethyl hexyl diphenyl phosphate , Dimethylmethyl phosphate, resorcinorbis (diphenyl) phosphate, bisphenol A bis (dicresyl) phosphate, resorcinorbis (di-2,6-xylenyl) phosphate, diethyl-N-N-bis (2hydroxyethyl) aminomethyl phosphate, silicone compounds , Hindered amine compounds, melamine compounds, guanidine compounds and the like.

  As a specific product example of the substrate of the present invention, as a non-halogen flame retardant-containing film, Toray Industries, Inc. Lumirror ZV-10, Torelina, Miktron, Toray DuPont Kapton, Mitsubishi Plastics Corporation Superior Examples include UT and dialermy. Also, LAXRON Polyca SDB-3 manufactured by Tokiwa Electric Co., Ltd., Fumilon manufactured by Wako Resin Co., Ltd., NF / Vertical manufactured by Takeda Sangyo Co., Ltd., Sunroid Barrier manufactured by Sumitomo Bakelite Co., Ltd. Barocks, Oida Industrial Co., Ltd. safety film, etc. are mentioned. Note that the present invention is not limited to these product examples.

  In addition, the surface of the substrate opposite to the surface to which the pressure-sensitive adhesive is applied is subjected to a surface coating treatment for printing / printing, a white coating treatment for concealing, aluminum deposition, etc. It may be.

(2) Pressure-sensitive adhesive The pressure-sensitive adhesive in the present invention is non-flame retardant, (a) acrylic pressure-sensitive adhesive, (b) rubber-based pressure-sensitive adhesive, (c) silicone-based feeling A pressure adhesive or the like can be used. These may also be solvent-based pressure sensitive adhesives, hot melt pressure sensitive adhesives, water based pressure sensitive adhesives, UV curable pressure sensitive adhesives, and the like.

(A) Acrylic pressure-sensitive adhesive As an acrylic pressure-sensitive adhesive, as a main component, for example, an acrylate ester homopolymer, a copolymer containing two or more acrylate ester units, an acrylate ester and other functions What contains at least 1 sort (s) chosen from the copolymer with an ionic monomer is used. Examples of the acrylate ester include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, n-butyl (meth) acrylate, (meth ) Isobutyl acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, isooctyl (meth) acrylate, n-octyl (meth) acrylate , N-nonyl (meth) acrylate, isononyl (meth) acrylate, decyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate , Myristyl (meth) acrylate, palmityl (meth) acrylate, (meth) Such as acrylic acid stearyl and the like. Examples of the functional monomer include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate. , (Meth) acrylic acid hydroxyalkyl esters such as (meth) acrylic acid 3-hydroxybutyl and (meth) acrylic acid 4-hydroxybutyl; (meth) acrylamide, N-methyl (meth) acrylamide, N-methylol (meth) Acrylamides such as acrylamide and dimethyl (meth) acrylamide; monomethylaminoethyl (meth) acrylate, monoethylaminoethyl (meth) acrylate, monomethylaminopropyl (meth) acrylate, monoethylaminopropyl (meth) acrylate, etc. No (meta) ak Le acid monoalkyl aminoalkyl; (meth) acrylic acid, crotonic acid, itaconic acid, maleic acid, ethylenically unsaturated carboxylic acids such as citraconic acid. Other monomers copolymerizable with the above monomers include aromatic vinyl compounds such as vinyl benzoic acid, styrene and α-methylstyrene; vinyl ester compounds such as vinyl acetate and vinyl propionate; vinyl glycidyl ether and the like. Examples thereof include vinyl ether compounds; conjugated diene compounds such as butadiene and isoprene; and alicyclic vinyl compounds such as N-vinyl-2-pyrrolidone.

(B) Rubber-based pressure-sensitive adhesive The rubber-based pressure-sensitive adhesive includes, for example, natural rubber, polyisoprene rubber, polyisobutylene, polybutadiene rubber, fluorine rubber, urethane rubber, butyl rubber, chloroprene rubber, acrylic rubber, as a main component. Ethylene-propylene-diene copolymer (EPDM rubber), styrene-isoprene copolymer, styrene-butadiene copolymer, styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-butadiene -What contains at least 1 sort (s) chosen from butylene-styrene copolymer, styrene-isobutylene copolymer, styrene-isobutylene-styrene copolymer, etc. is used.

(C) Silicone-based pressure-sensitive adhesive Examples of the silicone-based pressure-sensitive adhesive include those containing polydimethylsiloxane, polymethylphenylsiloxane, or polydiphenylsiloxane as a main component.

  The pressure-sensitive adhesive contains known additives such as a tackifier, a crosslinking agent, a wetting agent, a preservative, a thickener, a photoinitiator, an organic filler, and an inorganic filler softener as necessary. May be. 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.

  The thickness of the pressure-sensitive adhesive layer is preferably 5 to 60 μm, and particularly preferably 10 to 50 μm.

  Hereinafter, (3) adherend in the laminate using the pressure-sensitive adhesive sheet of the present invention described above will be described.

(3) Adherent As the adherend in the present invention, one that conforms to VTM-0 or V-0 in a test according to the UL94 standard can be used. Examples of the adherend include a plastic plate for electronic equipment, a film, and a housing. As such an adherend material, the same substrate as described in (1) can be used. Polyimide resin, polyphenylene sulfide resin, polyetherimide resin, polyphenylene etherimide resin, polyetheretherketone resin It is possible to use a film, a plastic plate, or the like that is made of a resin and has flame retardancy with a single resin. Also, flame retardant-containing polycarbonate resin, polystyrene resin, polyethylene resin, polyester resin, polyolefin resin, polyurethane resin, phenol resin, urea resin, EVA resin, acrylic resin, acrylonitrile butadiene resin (ABS resin), epoxy resin, polystyrene- Examples include a flame retardant film made of polycarbonate alloy resin, polystyrene-ABS alloy resin, polyamide resin, and the like. As the flame retardant herein, one or more of the flame retardants described in (1) can be used.

  The manufacturing method of the pressure sensitive adhesive sheet of this invention is demonstrated.

  First, a pressure-sensitive adhesive composition coating solution is prepared by diluting a pressure-sensitive adhesive composition with an organic solvent system, an emulsion system, or the like.

  And the obtained pressure sensitive adhesive composition coating liquid is apply | coated to a base material, and a pressure sensitive adhesive layer is formed. Under the present circumstances, in order to accelerate | stimulate bridge | crosslinking, a pressure-sensitive adhesive layer may be heat-processed, and heat processing temperature is 50-150 degreeC, for example. Moreover, you may laminate | stack a base material after apply | coating and drying the pressure-sensitive adhesive composition mentioned above with respect to the peeling surface of the peeling sheet prepared separately. The method for applying the pressure-sensitive adhesive composition 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.

  As a configuration of such a pressure-sensitive adhesive sheet, the total thickness of the base material and the pressure-sensitive adhesive is 35 to 200 μm, and the ratio of the thickness of the base material and the pressure-sensitive adhesive Is 1: 1 to 8: 1. By being in this range, when an adherend is provided on the pressure-sensitive adhesive sheet, VTM-0 can be obtained in a test according to sufficient flame retardancy, that is, UL94 standard. If this range cannot be satisfied, sufficient flame retardancy cannot be obtained.

  A release sheet may be laminated on the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet according to this embodiment. As the release sheet, conventionally known ones can be used. For example, at least one surface of a resin film such as polyethylene terephthalate or polypropylene is provided with a silicone release agent, a long-chain alkyl release agent, an alkyd resin release agent, etc. It is possible to use a release sheet that has been subjected to a release treatment. The thickness of the release sheet is usually about 10 to 200 μm, preferably about 20 to 100 μm.

  The laminate thus obtained is excellent in flame retardancy and conforms to VTM-0 in a test according to the UL94 standard.

  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, 95 parts by mass of n-butyl acrylate, 5 parts by mass of acrylic acid, 0.3 parts by mass of azobisisobutyronitrile, 150 parts by mass of ethyl acetate The nitrogen substitution was carried out over 1 hour. Then, it heated up at 70 degreeC and superposed | polymerized for 8 hours. When the molecular weight of the obtained polymer was measured by GPC (polystyrene conversion), the weight average molecular weight was about 400,000. 1.0 part by mass of an isocyanate-based crosslinking agent (trade name: L-45, manufactured by Soken Chemical Co., Ltd.) was added to the obtained polymer solution immediately before the adhesion processing to obtain a coating solution.

  The obtained coating solution is applied to a release film (product name SP-PET381031 manufactured by Lintec Corporation) using an applicator, heated and dried at 100 ° C. for 1 minute, and a pressure-sensitive adhesive layer having a thickness of about 20 μm. Then, a polyethylene terephthalate (PET) film (product name: Lumirror ZV-10 # 40, VTM-0 acquired product manufactured by Toray Industries, Inc., manufactured by Toray Industries, Inc.) with a double-sided polyimide coating treatment having a thickness of 45 μm is laminated, and pressure-sensitive adhesion of Example 1 A sheet was produced.

  Further, the release film was peeled off and attached to a 125 μm-thick polyimide film (product name: Kapton 500H, VTM-0 acquired product) as an adherend to obtain a laminate of Example 1.

(Example 2)
The pressure-sensitive adhesive sheet and laminate of Example 2 were obtained in the same manner as in Example 1 except that the thickness of the pressure-sensitive adhesive layer was 10 μm in Example 1.

(Example 3)
The pressure-sensitive adhesive sheet and laminate of Example 3 were obtained in the same manner as in Example 1 except that the thickness of the pressure-sensitive adhesive layer was 30 μm in Example 1.

Example 4
In Example 1, a polyethylene terephthalate film treated with a 25 μm double-sided polyimide coat was used instead of a 45 μm double-sided polyimide coated polyethylene terephthalate film (manufactured by Toray Industries, Inc., product name: Lumirror ZV-10 # 40, VTM-0 acquired product). A pressure-sensitive adhesive sheet and laminate of Example 4 were obtained in the same manner as in Example 1 except that a film (manufactured by Toray Industries, Inc., product name: Lumirror ZV-10 # 25, VTM-0 acquired product) was laminated.

(Example 5)
In Example 1, a polyethylene terephthalate film treated with 144 μm double-sided polyimide coating was replaced with a 45 μm double-sided polyimide coated polyethylene terephthalate film (manufactured by Toray Industries, Inc., product name: Lumirror ZV-10 # 40, VTM-0 acquired product). A pressure-sensitive adhesive sheet and laminate of Example 5 were obtained in the same manner as in Example 1 except that a film (manufactured by Toray Industries, Inc., product name: Lumirror ZV-10 # 140, VTM-0 acquired product) was laminated.

(Comparative Example 1)
In Example 1, a transparent polyethylene terephthalate film having a thickness of 50 μm (Toray Industries, Inc., product name: Lumirror ZV-10 # 40, VTM-0 acquired product manufactured by Toray Industries, Inc., manufactured by Toray Industries, Inc.) was treated with a double-sided polyimide coat of 45 μm. The pressure-sensitive adhesive sheet and laminate of Comparative Example 1 were obtained in the same manner as in Example 1 except that the product manufactured by Co., Ltd., product name: T-60, VTM-2 acquired product) was laminated.

(Comparative Example 2)
In Example 5, the pressure-sensitive adhesive sheet and laminate of Comparative Example 2 were obtained in the same manner as in Example 5 except that the thickness of the pressure-sensitive adhesive layer was 60 μm.

(Comparative Example 3)
In Example 4, the pressure-sensitive adhesive sheet and laminate of Comparative Example 3 were obtained in the same manner as in Example 4 except that the thickness of the pressure-sensitive adhesive layer was 80 μm.

(Comparative Example 4)
In Example 1, instead of the 125 μm-thick polyimide film as the adherend, Example 1 was used except that a 125 μm-thick PET film (product name: A4300, UL standard unacceptable product) was used. In the same manner as described above, the pressure-sensitive adhesive sheet and laminate of Comparative Example 4 were obtained.

  Table 1 summarizes the conditions of the examples and comparative examples. In addition, the flame retardant evaluation of the obtained pressure-sensitive adhesive laminate sample was carried out by peeling the release film of the pressure-sensitive adhesive sheet and applying the vertical combustion test method of UL94, a flammability test standard for plastic materials issued by Under Riders Laboratories. The UL94VTM rank was determined accordingly. The results are shown in Table 2.

  The base material conforms to VTM-0 in the test conforming to the UL94 standard, the total thickness of the base material and the pressure sensitive adhesive is 35 to 200 μm, and the thickness ratio of the base material to the pressure sensitive adhesive is 1. In Examples 1 to 5 which are: 1 to 8: 1, all conformed to VTM-0 in the test according to the UL94 standard. On the other hand, the comparative example that does not satisfy these requirements did not conform to VTM-0 in the test according to the UL94 standard. That is, Comparative Example 1 in which the base material does not conform to VTM-0 in the test conforming to the UL94 standard, Comparative Example 2 in which the total thickness of the base material and the pressure-sensitive adhesive is too thick, and the thickness of the base material and the pressure-sensitive adhesive In Comparative Example 3 in which the ratio is too low, a VTM-0-acquired base material is used as the base material, and in Comparative Example 4 in which the UL94 test rejected product is used as the adherend, both conform to VTM-0 in the test conforming to the UL94 standard. I never did.

Claims (3)

A pressure-sensitive adhesive sheet comprising a substrate and a non-flame retardant pressure-sensitive adhesive formed on the substrate,
The base material conforms to VTM-0 in a test according to UL94 standard,
The total thickness of the base material and the pressure-sensitive adhesive is 35 to 200 μm, and the thickness ratio of the base material and the pressure-sensitive adhesive is 1: 1 to 8: 1. Pressure sensitive adhesive sheet. A pressure-sensitive adhesive sheet according to claim 1,
A laminate comprising an adherend conforming to VTM-0 or V-0 in a test conforming to the UL94 standard on the opposite side of the base material of the pressure-sensitive adhesive. The laminate according to claim 2 conforms to VTM-0 in a test according to UL94 standard.