JP5118355B2 - Laminated adhesive sheet for metal decorative board - Google Patents

Description

  The present invention relates to a laminated adhesive sheet for a metal decorative board, and more particularly to a laminated adhesive sheet for a metal decorative board that is less likely to float or peel when attached to an adherend made of a three-dimensional metal material.

Conventionally, decorative sheets are used for interiors of buildings, surface decorations of joinery, interiors of vehicles, and the like. This decorative sheet is often used as a decorative plate by being bonded to a base material such as a metal plate, wood, plywood, laminated wood, or a wooden board such as a particle board or hard board.
As the decorative sheet, generally, a base sheet, a sheet having a printed layer and a transparent resin layer sequentially applied on one surface thereof, a colored base sheet, and a transparent resin layer applied on one surface thereof are used. In addition, those having an adhesive layer on the other surface of the base sheet in these decorative sheets are used. As the transparent resin layer, for example, a fluorine resin-containing layer, an acrylic resin-containing layer, or a layer containing a fluorine resin and an acrylic resin is known. Moreover, as a base material sheet, a vinyl chloride resin sheet, an acrylic resin sheet, etc. are used abundantly from a viewpoint of workability, a weather resistance, etc.
As such a decorative sheet, for example, (1) a decorative sheet including a base sheet containing an acrylic resin and a printed layer formed by printing, a fluororesin is provided on at least the surface of the base sheet. And a decorative sheet (for example, refer to Patent Document 1) having a fluorine-containing resin-containing layer containing acrylic resin at a specific ratio, and (2) a fluorine-containing terpolymer or A decorative pressure-sensitive adhesive sheet in which a surface layer containing a mixture of 100 parts by weight of a fluorine-based binary copolymer and 30 to 70 parts by weight of an acrylic resin is provided and a pressure-sensitive adhesive layer is laminated on the other surface ( For example, see Patent Document 2).
By the way, when a decorative sheet having a pressure-sensitive adhesive layer on the back side is attached to an adherend made of a metal material and used as a metal decorative plate, especially when attached to an adherend having a three-dimensional shape, it does not float or peel off. Less is required.
However, Patent Document 1 is a technique for obtaining a decorative sheet that is excellent in chemical resistance, transparency, and printability, and does not mention anything about floating and peeling when used as a metal decorative board. Patent Document 2 is a technique for obtaining a decorative pressure-sensitive adhesive sheet that is excellent in weather resistance and stain resistance, and is difficult to whiten when pulled. No mention is made like Reference 1.
JP 2006-281563 A JP-A-7-188619

  Under such circumstances, the present invention is less likely to float or peel off when attached to an adherend made of a metal material having a three-dimensional shape (hereinafter sometimes referred to as a metal-based adherend). It is made for the purpose of providing the laminated adhesive sheet for metal decorative boards.

The present inventors have conducted extensive studies to develop a laminated pressure-sensitive adhesive sheet for metal decorative plate having favorable properties described above, to obtain a knowledge described below.
Conventionally, in “adhesive strength by 180 ° peeling method” (hereinafter referred to as 180 ° peel adhesive strength) measured by JIS Z 0237, which is often used for measuring the adhesive strength of adhesive sheets, a three-dimensional metal When a laminated pressure-sensitive adhesive sheet is affixed to the adherend, the difference between the laminated pressure-sensitive adhesive sheet that is likely to be lifted or peeled off and the laminated pressure-sensitive adhesive sheet that is less likely to occur is unlikely to occur, and the test method according to JIS Z 0237 It was found that it was difficult to adopt as a discrimination method.
Therefore, the present inventors have further researched, created a constant load test method as a new test method, and measured the amount of peeling (displacement amount) after 24 hours to obtain a three-dimensional metal deposition. It has been found that the laminated adhesive sheet affixed to the body can be easily discriminated from those that are likely to be lifted or peeled off and those that are difficult to peel off.
Based on this knowledge, in the laminated pressure-sensitive adhesive sheet having a fluororesin-containing layer on one surface of the thermoplastic resin substrate film and having a pressure-sensitive adhesive layer on the other surface, the constant load test method is used for 24 hours. It has been found that those having a subsequent peeling amount of 10 mm or less can meet the object of the present invention.
The present invention has been completed based on such findings.
That is, the present invention

[1] A laminated adhesive sheet having a fluororesin-containing layer on one surface of a thermoplastic resin substrate film and an adhesive layer on the other surface , each of the fluororesin-containing layers being a 2-layer structure containing a fluorine-based resin and an acrylic resin in a layer of, and in the layer of the base film side, the content of the fluorine-based resin and an acrylic resin, the mass ratio 5:95 45:55, and in the other layer, the content ratio of the fluororesin and the acrylic resin is 55:45 to 95: 5 by mass ratio, and the pressure-sensitive adhesive layer contains butyl acrylate units. are those formed with an acrylic pressure-sensitive adhesive containing a resin component and an isocyanate-based crosslinking agent mainly, and properties by the constant load test described below, is the amount peeling after 24 hours 10mm or less Discriminated Metal veneer laminated pressure-sensitive adhesive sheet, characterized in that the,
Constant load test On a flat adherend made of stainless steel, a 50 mm portion of a laminated adhesive sheet (size: 25 mm x 100 mm, marked with a marked line at 50 mm) is affixed and allowed to stand for 24 hours at 23 ° C and 50% RH. Thereafter, a load of 1.96 N is applied in the direction of 90 ° to the end of the laminated adhesive sheet that is not attached, and the amount of peeling (deviation amount) after 24 hours is measured under the above conditions.
[ 2 ] In the following constant load test, the laminated pressure-sensitive adhesive sheet for metal decorative plates according to the above item [1] , wherein the characteristic is determined by the amount of peeling after 20 hours being 20 mm or less,
Constant load test On a flat adherend made of stainless steel, a 50 mm portion of a laminated adhesive sheet (size: 25 mm x 100 mm, marked with a marked line at 50 mm) is affixed and allowed to stand for 24 hours at 23 ° C and 50% RH. Thereafter, a load of 1.96 N is applied in the 90 ° direction to the end of the laminated adhesive sheet that is not attached under the dry condition of 40 ° C., and the amount of peeling (deviation amount) after 24 hours is measured.
[3] The laminated pressure-sensitive adhesive sheet for metal decorative plates according to the above [1] or [2], wherein the thermoplastic resin base film is made of a vinyl chloride resin.
[ 4 ] The laminated adhesive sheet for metal decorative plates according to any one of [1] to [ 3 ] above, wherein the metal of the metal decorative plate is aluminum or an aluminum alloy.
[5] The laminated pressure-sensitive adhesive sheet for metal decorative plates according to the above [4], wherein the pressure-sensitive adhesive layer contains a silane coupling agent, and
[6] The laminated pressure-sensitive adhesive sheet for metal decorative plates according to any one of [1] to [5], wherein the surface of the pressure-sensitive adhesive layer is covered with a release sheet,
Is to provide.

  ADVANTAGE OF THE INVENTION According to this invention, when it affixes on a three-dimensional-shaped metal type adherend, the lamination adhesive sheet for metal decorative boards with few floating or peeling can be provided.

The laminated pressure-sensitive adhesive sheet for metal decorative plates of the present invention (hereinafter sometimes simply referred to as a laminated pressure-sensitive adhesive sheet) has a fluororesin-containing layer on one surface of a thermoplastic resin substrate film, It is a laminated pressure-sensitive adhesive sheet having a structure having a pressure-sensitive adhesive layer on the surface.
There is no restriction | limiting in particular in the base film in the laminated adhesive sheet of this invention, Arbitrary things are suitably selected from the well-known films conventionally used as a base film of the decorative sheet used for a metal decorative board. Can be used. Such base films include thermoplastic resins such as acrylic resins, vinyl chloride resins, polystyrene resins, ABS resins, polyolefin resins, polyester resins, polycarbonate resins, and pigments and dyes. The usual various films are mentioned. Among these, a vinyl chloride resin film and an acrylic resin film are preferable from the viewpoint of shape followability, workability, weather resistance, and the like.
Examples of the vinyl chloride resin material constituting the vinyl chloride resin film include, for example, polyvinyl chloride having a number average degree of polymerization of about 800 to 2500, and a copolymer mainly composed of vinyl chloride (for example, ethylene-vinyl chloride copolymer). , Vinyl acetate-vinyl chloride copolymer, vinyl chloride-halogenated olefin copolymer, etc.), or other compatible resins based on these polyvinyl chloride or vinyl chloride copolymers (for example, polyester resins, epoxies) Resin, acrylic resin, vinyl acetate resin, urethane resin, acrylonitrile-styrene-butadiene copolymer, partially saponified polyvinyl alcohol, and the like. The polyvinyl chloride or the copolymer mainly composed of vinyl chloride may be obtained by any conventional production method such as bulk polymerization, emulsion polymerization, suspension polymerization, and solution polymerization. These vinyl chloride resins may be used singly or in combination of two or more.
This vinyl chloride resin material can be prepared by blending about 20 to 50 parts by mass of a plasticizer with respect to 100 parts by mass of the vinyl chloride resin. Moreover, stabilizers, such as a lead salt stabilizer, a metal soap stabilizer, and an organic tin stabilizer, can be blended as necessary.

Meanwhile, the acrylic resin constituting the acrylic resin film such as a poly (meth) acrylate, poly (meth) acrylate, poly (meth) acrylic acid propyl, poly (meth) acrylate, butyl (meth ) Methyl acrylate- (meth) butyl acrylate copolymer, (meth) ethyl acrylate- (meth) butyl acrylate copolymer, ethylene-methyl (meth) acrylate copolymer, styrene- (meth) acryl Examples thereof include a resin comprising a homopolymer or a copolymer containing a (meth) acrylic acid ester such as an acid methyl copolymer. In addition, (meth) acryl means acryl or methacryl. These acrylic resins may be used alone or in combination of two or more.
For the thermoplastic resin constituting the base film, various additives as necessary, for example, antioxidants, ultraviolet absorbers, light stabilizers, flexibility imparting agents, flame retardants, antistatic agents, foaming agents, lubricants In addition, fillers, colorants and the like can be appropriately blended.
There are no particular restrictions on the film forming method, and there are known methods such as solution casting (casting), melt extrusion (extrusion), inflation, calendering, sol casting, etc. It can select suitably according to the kind of resin.
The film thus formed can be subjected to uniaxial stretching treatment or biaxial stretching treatment as necessary. Although there is no restriction | limiting in particular in the thickness of a base film, Usually, about 50-300 micrometers, Preferably it is 100-200 micrometers.
In the present invention, the base film is formed on one side or both sides as desired by an oxidation method, an unevenness method, or the like for the purpose of improving the adhesiveness with the pressure-sensitive adhesive layer or the fluororesin-containing layer provided thereon. Surface treatment can be applied. Examples of the oxidation method include corona discharge treatment, plasma treatment, chromic acid treatment (wet), flame treatment, hot air treatment, ozone / ultraviolet irradiation treatment, and examples of the unevenness method include a sand blast method, a solvent, and the like. Treatment methods and the like. These surface treatment methods are appropriately selected depending on the type of the substrate, but in general, the corona discharge treatment method is preferably used from the viewpoints of effects and operability. Moreover, what gave the primer process to the single side | surface or both surfaces can also be used.

In the laminated pressure-sensitive adhesive sheet of the present invention, a printing layer such as a solid printing layer or a pattern layer can be applied to the bonding surface of the base film with the fluororesin-containing layer by a conventionally known means, if necessary. .
In the laminated pressure-sensitive adhesive sheet of the present invention, the fluororesin-containing layer provided on one surface of the base film is preferably a layer containing a fluororesin and an acrylic resin, and examples of the fluororesin include a polyfluoride resin. Vinylidene fluoride (PVDF), ethylene-tetrafluoroethylene copolymer, ethylene trifluoride chloride, tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer, vinylidene fluoride, vinyl fluoride, perfluoro-perfluoropropylene- Examples include perfluorovinyl ether copolymer, polytetrafluoroethylene (PTFE), tetrafluoroethylene-hexafluoropropylene copolymer (FEP), and tetrafluoroethylene-ethylene copolymer (ETFE). These may be used individually by 1 type and may be used in combination of 2 or more type.
Examples of the acrylic resin include poly (meth) methyl acrylate, poly (meth) ethyl acrylate, poly (meth) acrylate propyl, poly (meth) acrylate butyl, and (meth) acrylate methyl- (meth). (Butyl acrylate copolymer, (meth) ethyl acrylate- (meth) butyl acrylate copolymer, ethylene- (meth) methyl acrylate copolymer, styrene- (meth) methyl acrylate copolymer, etc. Examples thereof include resins made of a homopolymer or a copolymer containing a (meth) acrylic ester. These may be used individually by 1 type and may be used in combination of 2 or more type.

In the laminated adhesive film of the present invention, fluorine-based resin-containing layer provided on one surface of the substrate film preferably has a two-layered structure including a fluorine-based resin and an acrylic resin in each layer. And in the layer by the side of a base film, from a viewpoint of the intensity | strength at the time of laminating | stacking on a base film, the content rate of fluororesin and acrylic resin is 5: 95-45: 55 by mass ratio. Is preferable, and it is more preferable that it is 10: 90-40: 60.
In the other layer, from the viewpoint of weather resistance, the content ratio of the fluororesin and the acrylic resin is preferably 55:45 to 95: 5 by mass ratio, and 60:40 to 90 : 10 is more preferable.
Each fluorine-containing resin-containing layer has various additives as necessary, for example, an antioxidant, an ultraviolet absorber, a light stabilizer, a flexibility imparting agent, a flame retardant, an antistatic agent, a foaming agent, a lubricant, and a filler. A coloring agent, a coloring agent, etc. can be contained suitably. There is no restriction | limiting in particular in the manufacturing method of this fluororesin content layer of 2 layer laminated structure, For example, it can manufacture by a coextrusion method etc.
In the present invention, the thickness of the fluororesin-containing layer is not particularly limited, but is usually about 10 to 50 μm. Further, the thickness ratio of the base film / fluorine-based resin-containing layer is preferably about 100/5 to 100/40, more preferably 100/10 to 100/30, from the viewpoints of transparency, cost, manufacturing suitability, and the like. .
Although there is no restriction | limiting in particular in the joining method of a base film and a fluorine-type resin content layer, The dry lamination method by the method using adhesives, heat sealing, etc. can be used.

In the laminated pressure-sensitive adhesive sheet of the present invention, the pressure-sensitive adhesive layer is provided on the opposite surface of the base film on the side where the fluororesin-containing layer is provided. The pressure-sensitive adhesive that can be used for this pressure-sensitive adhesive layer is not particularly limited, and various pressure-sensitive adhesives mainly composed of an acrylic pressure-sensitive adhesive, a rubber-based pressure-sensitive adhesive, or a silicone-based pressure-sensitive adhesive can be used. An acrylic pressure-sensitive adhesive is preferably used from the viewpoint of suitability for application to a metal-based adherend. For example, acrylic resins constituting the acrylic adhesive include ethyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and n-pentyl (meth) acrylate. 2-methylbutyl (meth) acrylate, n-hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) ) At least one C2-C12 alkyl ester of (meth) acrylic acid such as acrylate (monomer A) and acrylic acid, methacrylic acid, acrylamide, N-methylolacrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, etc. Functional group containing a At least one drill-based monomer and (monomers B) can be exemplified those obtained by being copolymerized. Copolymerization ratio of the monomers A and B is preferably from 99.5 / 0.5 to 70/30 in mass ratio of the monomer A / monomer B, more preferably in the range of 99 / 1-75 / 25. In particular, butyl acrylate (BA) and acrylic acid (AA) are copolymerized within a mass ratio of BA / AA of preferably 98/2 to 80/20, more preferably 95/5 to 85/15. The copolymer obtained by this is preferably used from the point of a constant load test.
The acrylic resin preferably has a weight average molecular weight (Mw) of 200,000 to 1,000,000, more preferably 400,000 to 800,000, and this molecular weight depends on the amount of the polymerization initiator or a chain transfer agent is added. Can be adjusted.

As the adhesive, particularly those containing a resin component mainly comprising butyl acrylate units crosslinking agent, weather resistance, from the viewpoint of sticking suitability for metallic adherend.
Examples of the crosslinking agent include polyisocyanate compounds, epoxy resins, melamine resins, urea resins, dialdehydes, methylol polymers, aziridine compounds, metal chelate compounds, metal alkoxides, metal salts, and the like. A polyisocyanate compound which is a crosslinking agent is preferably used. This crosslinking agent can be blended in an amount of about 0.1 to 10 parts by mass with respect to 100 parts by mass of the solid content of the (meth) acrylic acid ester copolymer.
Here, examples of the polyisocyanate compound include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate and xylylene diisocyanate, aliphatic polyisocyanates such as hexamethylene diisocyanate, and isophorone diisocyanate. Nalto, cycloaliphatic polyisocyanates such as hydrogenated diphenylmethane diisocyanate, etc., and their biurets, isocyanurates, and low molecular weights such as ethylene glycol, propylene glycol, neopentyl glycol, trimethylolpropane, castor oil The adduct body etc. which are a reaction material with an active hydrogen containing compound can be mentioned. These crosslinking agents may be used individually by 1 type, and may be used in combination of 2 or more type.

The pressure-sensitive adhesive includes a tackifier, a softener, a leveling agent, a silane coupling agent, a filler, a coloring agent such as a dye or a pigment, an ultraviolet absorber, a light stabilizer, and an antioxidant as necessary. A weathering assistant or the like can be contained. In particular, when the adherend is aluminum, it is preferable to add a silane coupling agent from the viewpoint of suitability for sticking.
Examples of the silane coupling agent include triethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, and β- (3,4-epoxy. (Cyclohexyl) ethyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) -γ-aminopropylmethyldimethoxysilane, γ-aminopropyltriethoxysilane, N -Phenyl-γ-aminopropyltrimethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-chloropropyltrimethoxysilane and the like. Among these γ- aminopropyltriethoxysilane, N-beta-amino silanes such as (aminoethyl)-.gamma.-aminopropyltrimethoxysilane is preferred.
This silane coupling agent may be used individually by 1 type, and may be used in combination of 2 or more type. Moreover, the compounding quantity is about 0.01-0.5 mass part with respect to 100 mass parts of solid content of the above-mentioned (meth) acrylic acid ester copolymer.

The pressure-sensitive adhesive layer may be directly applied and formed on one side of the base film, and after the pressure-sensitive adhesive is applied to the release treatment surface of the release sheet and dried to form the pressure-sensitive adhesive layer, You may stick together. Various methods can be used as the method for forming the pressure-sensitive adhesive layer without any particular limitation. For example, an air knife coater, blade coater, bar coater, gravure coater, roll coater, curtain coater, die coater, knife coater, screen coater , Mayer bar coaters, kiss coaters and the like.
The thickness of an adhesive layer is about 10-100 micrometers normally, Preferably it is 30-80 micrometers.
The surface of the pressure-sensitive adhesive layer is preferably covered with a release sheet in order to protect it. Any release sheet may be used. For example, films made of various resins such as polyethylene terephthalate, polybutylene terephthalate, polyethylene, polypropylene, polyarylate, polyethylene laminated paper, polypropylene laminated paper, clay coat Various paper materials such as paper, resin-coated paper, glassine paper, and high-quality paper can be used as the base material, and the surface of the base material bonded to the pressure-sensitive adhesive layer can be peeled off as necessary.
In this case, a typical example of the release treatment includes formation of a release agent layer made of a release agent such as a silicone resin, a long-chain alkyl resin, or a fluorine resin.
The thickness of the release sheet is not particularly limited and may be appropriately selected.

The laminated adhesive sheet of the present invention conforms to JIS Z 0237 for 50 mm of laminated adhesive sheet (size: 25 mm × 100 mm, marked line at 50 mm) on a flat adherend made of stainless steel (SUS # 360). Then, 50 mm of the release sheet of the pressure-sensitive adhesive sheet is peeled off, pasted once by a 2 kg roll on the adherend, and left for 24 hours at 23 ° C. and 50% RH. Is applied to the end of the laminated adhesive sheet that is not attached, and a load of 1.96 N is applied in the 90 ° direction (with a 200 g weight), and the amount of peeling (displacement) after 24 hours is measured under the above conditions. In the constant load test, peeling after 24 hours is required to be 10 mm or less. Preferably it is 5 mm or less, More preferably, it is 3 mm or less. Similarly, after applying for 24 hours under conditions of 23 ° C. and 50% RH, a load of 1.96 N was applied in the 90 ° direction to the end of the laminated adhesive sheet that was not attached under the conditions of 40 ° C. and dry. It is important that the amount of peeling (deviation amount) after 24 hours is 20 mm or less. Preferably it is 10 mm or less, More preferably, it is 5 mm or less.
A laminated pressure-sensitive adhesive sheet having such characteristics can be obtained by appropriately selecting the type of pressure-sensitive adhesive and the thickness of the pressure-sensitive adhesive layer.
Conventionally, in the 180 ° peel adhesive force measured by JIS Z 0237, which is often used for measuring the adhesive strength of an adhesive sheet, when a laminated adhesive sheet is affixed to a three-dimensional metallic adherend, The laminated adhesive sheet that is easily peeled off and the laminated adhesive sheet that is less likely to be peeled off are not easily different, but according to the constant load test method, when pasted on a three-dimensional metallic adherend, A laminated pressure-sensitive adhesive sheet that is unlikely to float or peel off can be easily identified.
The laminated pressure-sensitive adhesive sheet having the above characteristics is less likely to float or peel when attached to a three-dimensional metal adherend.
The laminated pressure-sensitive adhesive sheet of the present invention is used for a metal decorative board. The metal-based adherend to which the laminated adhesive sheet is attached is not particularly limited, and examples thereof include a plate made of aluminum or an aluminum alloy, a three-dimensional article or sheet, and various steel plates such as a stainless steel plate. An adherend made of aluminum or an aluminum alloy is preferable.
Metal decorative plate laminated pressure-sensitive adhesive sheet is affixed to the present invention, for example, interior of buildings, joinery surface decoration, used like interior of the vehicle.

EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by these examples.
In addition, the performance of the laminated adhesive sheet obtained in each example was calculated | required by the method shown below.
(1) Constant load test A laminated adhesive sheet having a size of 25 mm x 100 mm was prepared, stuck to an adherend so that the sticking area was 25 mm x 50 mm, and stuck after being left for 24 hours in an environment of 23 ° C and 50% RH. over no laminated adhesive sheet end load 1.96N to 90 ° direction of the environment or 40 ° C., to measure the peeled amount of 24 hours at the conditions of drying. Stainless steel was used for the adherend.
(2) 180 ° peel adhesive strength (JIS Z 0237)
The laminated adhesive sheet of 25mm × 200mm, 23 ℃, the adhesion area under 50% RH environment affixed to an adherend to be 25 mm × 100 mm. 24 hours after sticking, the laminated adhesive sheet is peeled from the adherend in the direction of 180 ° in an environment of 23 ° C. and 50% RH. The adhesive strength at that time was measured.
(3) Actual press test A laminated adhesive sheet was bonded to a 1 mm aluminum plate, cured for one week at 23 ° C and 50% RH, and then three-dimensional with a diameter of 170.5 mm and a depth of 20 mm using a 200 t hydraulic press. The shape is pressed and floating is confirmed after 5 cycles of a cycle test with 1 cycle of 80 ° C. × 5 hours.
○ ・ ・ ・ ・ No floating △ ・ ・ ・ ・ Slight floating × ・ ・ ・ ・ With floating

Production Example 1 Production of Laminated Base Sheet One side of a polyvinyl chloride film having a degree of polymerization of 800 and a thickness of 110 μm, a film A having a thickness of 20 μm with a polymethyl methacrylate (PMMA): PVDF mass ratio of 80:20 and a thickness of 20 μm The film having the other surface laminated with a film B having a PMMA: PVDF mass ratio of 20:80 and a thickness of 10 μm [manufactured by Denki Chemical Co., Ltd., trade name “DENKA DX film DX-14S30”, thickness 30 μm] The A side was dry laminated by heat fusion to produce a laminated base sheet.

Example 1
Using a reactor equipped with a thermometer, a stirrer, a reflux condenser, and a nitrogen gas inlet tube, 90 parts by mass of butyl acrylate (BA) and 10 parts by mass of acrylic acid (AA) were charged, and azobisisobutyronitrile was added in an amount of 0. 3 parts by mass was added, and polymerization was performed at 80 ° C. for 8 hours in a nitrogen gas atmosphere. After completion of the reaction, the solid content was adjusted to 34% by mass with toluene to obtain an acrylic copolymer solution having a weight average molecular weight of 500,000 and a BA / AA composition ratio (BA / AA mass ratio) of 90:10. . An acrylic pressure-sensitive adhesive coating solution was prepared by adding 2 parts by mass of an isocyanate-based crosslinking agent [trade name “BHS8515”, solid content: 37.5% by mass] to 100 parts by mass of this copolymer solution.
Next, the acrylic pressure-sensitive adhesive coating liquid is applied to the release-treated surface of a release sheet [manufactured by LINTEC, trade name “SP-10NL RB-5”, thickness 100 μm] and dried to give an adhesive layer (thickness 65 μm). after forming the, by bonding the polyvinyl chloride film surface of the laminated base material sheet obtained in production example 1 and its release-sheet laminated adhesive layer to prepare a multilayer adhesive sheet.
The performance evaluation results of this laminated adhesive sheet are shown in Table 1.

Example 2
A silane coupling agent [trade name “DOW CORNING Z-6040 (R) SILANE” manufactured by Toray Dow Corning Co., Ltd.]] was added to the acrylic pressure-sensitive adhesive coating liquid prepared in Example 1, and the solid content of the acrylic pressure-sensitive adhesive coating liquid was 100. A laminated pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that 0.03 part by mass was contained with respect to part by mass.
The performance evaluation results of this laminated adhesive sheet are shown in Table 1.
Comparative Example 1
In Example 1, the BA / AA mass ratio 90:10 was changed to 2-ethylhexyl acrylate (2EHA) / AA mass ratio 47/53, and an epoxy crosslinking agent [Nippon Carbite Industries, Ltd. instead of an isocyanate crosslinking agent] A laminated pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that 1 part by mass, manufactured by the company, trade name “CK101”, solid content 45 mass%] was used.
The performance evaluation results of this laminated adhesive sheet are shown in Table 1.
Comparative Example 2
In Example 1, a laminated pressure-sensitive adhesive sheet was produced in the same manner as in Example 1 except that 1 part by mass of the epoxy-based crosslinking agent “CK101” (supra) was used instead of the isocyanate-based crosslinking agent.
The performance evaluation results of this laminated adhesive sheet are shown in Table 1.
Comparative Example 3
In Example 1, it implemented except having used 1 mass part of chelate type crosslinking agents [The product name "M-5A" by the Soken Chemicals company, solid content 4.95 mass%] instead of the isocyanate type crosslinking agent. A laminated pressure-sensitive adhesive sheet was produced in the same manner as in Example 1.
The performance evaluation results of this laminated adhesive sheet are shown in Table 1.

  As can be seen from Table 1, the laminated adhesive sheets of the present invention (Examples 1 and 2) have a small amount of peeling (amount of deviation) in the constant load test, and no occurrence of lifting is observed in the actual press test. Further, from the data of 180 ° peel adhesive strength of Examples 1 and 2 and Comparative Example 1, it is difficult to determine whether or not the press work is good.

  The laminated pressure-sensitive adhesive sheet of the present invention is used for a metal decorative board, and has little floating and peeling when it is attached to a three-dimensional metallic adherend.

Claims (6)

A laminated adhesive sheet having a fluororesin-containing layer on one surface of a thermoplastic resin substrate film and an adhesive layer on the other surface, wherein the fluororesin-containing layer is formed on each layer. a 2-layer structure containing a fluorine-based resin and an acrylic resin, and in the layer of the base film side, the content of the fluorine-based resin and an acrylic resin, a mass ratio of 5: 95-45: 55 In the other layer, the content ratio of the fluororesin and the acrylic resin is 55:45 to 95: 5 in mass ratio, and the pressure-sensitive adhesive layer is mainly composed of butyl acrylate units. It was formed using an acrylic pressure-sensitive adhesive containing a resin component and an isocyanate-based cross-linking agent, and in the following constant load test, the characteristics were determined by the amount of peeling after 24 hours being 10 mm or less. Octopus Metal veneer laminated pressure-sensitive adhesive sheet according to claim.
Constant load test On a flat adherend made of stainless steel, a 50 mm portion of a laminated adhesive sheet (size: 25 mm x 100 mm, marked with a marked line at 50 mm) is affixed and allowed to stand for 24 hours at 23 ° C and 50% RH. Thereafter, a load of 1.96 N is applied in the direction of 90 ° to the end of the laminated adhesive sheet that is not attached, and the amount of peeling (deviation amount) after 24 hours is measured under the above conditions. In constant load test described below, the laminated pressure-sensitive adhesive sheet metal decorative plate according to claim 1, the characteristic is determined by amount peeling after 24 hours is 20mm or less.
Constant load test On a flat adherend made of stainless steel, a 50 mm portion of a laminated adhesive sheet (size: 25 mm x 100 mm, marked with a marked line at 50 mm) is affixed and allowed to stand for 24 hours at 23 ° C and 50% RH. Thereafter, a load of 1.96 N is applied in the 90 ° direction to the end of the laminated adhesive sheet that is not attached under the dry condition of 40 ° C., and the amount of peeling (deviation amount) after 24 hours is measured. The laminated adhesive sheet for a metal decorative board according to claim 1 or 2, wherein the thermoplastic resin base film is made of a vinyl chloride resin. The laminated adhesive sheet for a metal decorative board according to any one of claims 1 to 3 , wherein the metal of the metal decorative board is aluminum or an aluminum alloy. The laminated adhesive sheet for metal decorative plates according to claim 4, wherein the adhesive layer contains a silane coupling agent. The laminated pressure-sensitive adhesive sheet for metal decorative plates according to any one of claims 1 to 5, wherein the surface of the pressure-sensitive adhesive layer is covered with a release sheet.