JP2018002891A - Decorative film and decorative molding having the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a decorative film excellent in adhesiveness under high temperature and high humidity and adhesiveness to a curved surface, and to provide a decorative molding having the same.SOLUTION: A decorative film has an adhesive layer including an adhesive composition containing a vinyl polymer (A), an acrylic adhesive polymer (B), and a crosslinking agent on at least one surface of a base material. When the adhesive composition is coated to a separator and is dried to obtain an adhesive layer, a first Tg that is a glass transition temperature of the whole adhesive layer is -80°C or higher and 10°C or lower, and a second Tg that is a glass transition temperature calculated from a surface layer portion of the adhesive layer obtained by X-ray photoelectron spectroscopy is higher than that the first Tg by 30°C or higher.SELECTED DRAWING: None

Description

  The present specification relates to a decorative film and a decorative molded body including the decorative film. In detail, it is related with a decorative film provided with favorable adhesiveness under high temperature and high humidity, and a decorative molded body provided with the same.

  The pressure-sensitive adhesive (also referred to as a pressure-sensitive adhesive) is processed into a form such as a tape or a label, and is used in a wide range of applications. Further, the adherend is also applied to various substances such as plastic, paper, metal, glass and ceramics.

  Furthermore, the pressure-sensitive adhesive is also used for a decorative film for the purpose of protecting members such as home appliances or automobile interior products and imparting design properties. The decorative film is manufactured by laminating a decorative layer, an adhesive layer, and the like on a base material layer made of a vinyl chloride resin or a polyolefin resin. A decorative film having such a pressure-sensitive adhesive layer is disclosed in Patent Document 1.

  Patent Document 2 discloses a pressure-sensitive adhesive composition that exhibits good adhesiveness at high temperatures by segregating a vinyl polymer as a tackifier on the surface layer of the pressure-sensitive adhesive layer. It is described that this pressure-sensitive adhesive composition is used for pressure-sensitive adhesive films, pressure-sensitive adhesive sheets, pressure-sensitive adhesive tapes, labels, and the like.

JP 2012-213894 A JP 2014-088549 A

  In the use of the decorative film, a performance capable of following a complicated shape having a curved surface or an uneven portion and exhibiting good adhesiveness even under high temperature conditions is required. In addition, when a decorative film is bonded to a plastic molded body, air bubbles (foaming) are generated from the plastic substrate, etc. when exposed to high-temperature and high-humidity conditions for a long time, and floats at the adhesive interface with the adhesive layer. Peeling may occur. The decorative film is required to have excellent durability without causing such appearance defects.

  Although the decorative film of Patent Document 1 has good adhesion at room temperature, there are concerns about performance such as adhesion at high temperatures. Further, the adhesiveness to the curved surface is not sufficient.

  The present specification describes a decorative film as a novel use of a pressure-sensitive adhesive composition, which has excellent adhesion at high temperatures and high humidity and adhesion to a curved surface, and does not cause the above-mentioned problems, and a coating provided with the same. A decorative molded body is provided.

  As a result of intensive studies in view of the above problems, the present inventors have paid attention to a pressure-sensitive adhesive composition containing an acrylic pressure-sensitive adhesive polymer and a low molecular weight vinyl polymer. That is, when forming a pressure-sensitive adhesive layer with a pressure-sensitive adhesive composition containing a predetermined acrylic pressure-sensitive adhesive polymer and a vinyl polymer having a predetermined molecular weight range, the low molecular weight vinyl polymer is formed on the surface of the pressure-sensitive adhesive layer. I have learned that segregation is possible. And as a novel use of this pressure-sensitive adhesive composition, it was found that it can be used for the decorative film as described above. According to the present specification, the following means are provided.

[1] A decorative film comprising an adhesive layer containing an adhesive composition containing a vinyl polymer (A) and an acrylic adhesive polymer (B) on at least one surface of a substrate,
The vinyl polymer (A) has a glass transition temperature (Tg) of 30 ° C. or more and 200 ° C. or less, a number average molecular weight of 500 to 10,000, and 100 parts by mass of the acrylic adhesive polymer (B). 0.5 parts by mass or more and 60 parts by mass or less based on
When the pressure-sensitive adhesive composition is applied to a separator and dried to obtain a pressure-sensitive adhesive layer, the first Tg, which is the glass transition temperature of the pressure-sensitive adhesive layer as a whole, is −80 ° C. or higher and 10 ° C. or lower,
The second Tg, which is the glass transition temperature calculated from the surface layer portion obtained by X-ray photoelectron spectroscopy of the pressure-sensitive adhesive layer, is 30 ° C. or more higher than the first Tg.
Decorative film.
[2] The acrylic adhesive polymer (B) contains 85% by mass or more of a structural unit derived from an alkoxyalkyl ester of (meth) acrylic acid with respect to all the constituent monomers. Decorative film.
[3] The decorative film according to [1] or [2], wherein the adhesive layer has a haze value of 2.0 or less.
[4] The peel strength of the pressure-sensitive adhesive sheet provided with a 100 μm-thick polyethylene terephthalate film substrate with a pressure-sensitive adhesive layer having a thickness of 50 μm made of the pressure-sensitive adhesive composition is 3.0 N / 25 mm or more at 85 ° C. The decorative film according to any one of [1] to [3].
[5] A decorative molded body obtained by sticking the decorative film according to any one of [1] to [4] to a molded body.

  According to the decorative film including the pressure-sensitive adhesive layer containing the pressure-sensitive adhesive composition disclosed in the present specification (hereinafter also referred to as the present pressure-sensitive adhesive composition), the pressure-sensitive adhesive layer is subjected to high temperature and high humidity and against a curved surface. In addition, since sufficient adhesiveness can be exhibited, practical adhesiveness can be obtained. Moreover, a decorating molded object provided with such a decorating film can be obtained.

  The present specification relates to a decorative film having a pressure-sensitive adhesive layer excellent in adhesiveness under high temperature conditions and adhesiveness to a curved surface, and a decorative molded body including the decorative film.

  This pressure-sensitive adhesive composition contains a vinyl polymer (A) having a certain glass transition temperature and a number average molecular weight and an acrylic pressure-sensitive adhesive polymer (B), and the vinyl polymer (A) is used as a surface layer of the pressure-sensitive adhesive layer. It is possible to control the glass transition temperature of the surface layer of the pressure-sensitive adhesive layer by segregating. The pressure-sensitive adhesive layer obtained from the present pressure-sensitive adhesive composition has excellent curved surface adhesion and durability as well as excellent adhesion under high temperature and high humidity conditions.

  The segregation behavior of the vinyl polymer (A) on the surface of the pressure-sensitive adhesive layer when forming a pressure-sensitive adhesive layer with the present pressure-sensitive adhesive composition is determined by the specific vinyl polymer (A) and the acrylic pressure-sensitive adhesive polymer (B ) And are not completely compatible, but not completely phase separated. Preferably, the vinyl polymer (A) has a lower polarity than the acrylic adhesive polymer (B).

  As described above, the pressure-sensitive adhesive composition uses a vinyl polymer (A) that is not completely compatible with the acrylic pressure-sensitive adhesive polymer (B). At that time, the degree of segregation can be adjusted by appropriately adjusting the amount of the vinyl polymer (A) used in the pressure-sensitive adhesive composition. If the amount of the vinyl polymer (A) used is too small, segregation on the surface of the pressure-sensitive adhesive layer becomes insufficient, and a sufficient effect may not be obtained. On the other hand, when there is too much usage-amount of a vinyl polymer (A), as a result of phase-separating with an acrylic adhesive polymer (B), there exists a tendency for transparency and adhesive performance of an adhesive layer to fall. In addition, the glass transition temperature of the vinyl polymer (A), the amount of the crosslinking agent, and the like are appropriately adjusted, whereby the glass transition temperature of the surface layer portion of the pressure-sensitive adhesive layer can be adjusted.

  Furthermore, such a pressure-sensitive adhesive layer according to the present pressure-sensitive adhesive composition can suppress the lifting and peeling of the pressure-sensitive adhesive layer even when there is outgas from the adherend at high temperatures, and can exhibit good adhesion durability.

  The segregation of the vinyl polymer (A) occurs when the pressure-sensitive adhesive layer is formed, and the vinyl polymer (A) is segregated on the surface layer side (air interface side) where the solvent evaporates. Therefore, for example, when two surface layers opposed in the thickness direction in the sheet-like or film-like pressure-sensitive adhesive layer of the present pressure-sensitive adhesive composition are in contact with a substance having a low surface energy such as a gas or a certain solid, such a substance. A pressure-sensitive adhesive layer containing a vinyl polymer (A) at a higher concentration on the low surface energy interface side in contact with the pressure-sensitive adhesive layer and a vinyl polymer (A) at a lower concentration on the central side in the thickness direction of the pressure-sensitive adhesive layer. Can be obtained. That is, a pressure-sensitive adhesive layer having a gradient composition having a higher concentration of the vinyl polymer (A) on the surface layer side of the pressure-sensitive adhesive layer can be obtained. From the viewpoint of the acrylic pressure-sensitive adhesive polymer (B), a pressure-sensitive adhesive layer having a gradient composition having the acrylic pressure-sensitive adhesive polymer (B) at a lower concentration on the surface layer side of the pressure-sensitive adhesive layer can be obtained.

  For example, when only one surface of the two surface layers opposed in the thickness direction in the sheet-like or film-like pressure-sensitive adhesive layer of the present pressure-sensitive adhesive composition is the low surface energy interface side, A pressure-sensitive adhesive layer containing the coalescence (A) at a higher concentration can be obtained.

  As for this adhesive composition, Tg calculated from the composition of the surface layer part obtained by the X-ray photoelectron spectroscopy analysis of an adhesive layer as a result of segregation of the vinyl polymer (A) in an adhesive layer is the whole adhesive layer. It can be made 30 ° C. or higher than the Tg. Thereby, the adhesive characteristic of an adhesive layer can be controlled and favorable adhesive strength can be obtained. That is, since a relatively high Tg is provided in the vicinity of the adhesive interface constituted by the surface layer of the pressure-sensitive adhesive, it is possible to exhibit good adhesiveness that has not been achieved in the past. For example, even when the temperature is high, the pressure-sensitive adhesive layer can be prevented from floating and peeling off, and good durability can be exhibited. Moreover, it can have favorable adhesiveness with respect to a curved surface.

  Hereinafter, the disclosure of this specification will be described in detail. In the present specification, “(meth) acryl” means acryl and / or methacryl, and “(meth) acrylate” means acrylate and / or methacrylate. The “(meth) acryloyl group” means an acryloyl group and / or a methacryloyl group.

  This pressure-sensitive adhesive composition contains a vinyl polymer (A) and an acrylic pressure-sensitive adhesive polymer (B). Details of the vinyl polymer (A), the acrylic pressure-sensitive adhesive polymer (B), and the pressure-sensitive adhesive composition containing these will be sequentially described below.

[Vinyl polymer (A)]
The vinyl polymer (A) disclosed in the present specification can be a polymer having a glass transition temperature (Tg) of 30 ° C. or higher and 200 ° C. or lower. The minimum with preferable Tg is 40 degreeC or more, More preferably, it is 50 degreeC or more, More preferably, it is 60 degreeC or more, More preferably, it is 70 degreeC or more. The upper limit with preferable Tg is 180 degrees C or less, More preferably, it is 150 degrees C or less, More preferably, it is 120 degrees C or less, More preferably, it is 110 degrees C or less, More preferably, it is 100 degrees C or less. Moreover, the more preferable range of Tg is 50 degreeC or more and 180 degrees C or less, More preferably, they are 60 degreeC or more and 150 degrees C or less. In the present specification, a value measured by differential scanning calorimetry (DSC) at a heating rate of 10 ° C./min is adopted as Tg. When the Tg is less than 30 ° C., the Tg of the surface layer portion of the pressure-sensitive adhesive layer is hardly sufficiently high, the adhesive strength to various adherends is not sufficient, and the durability may be inferior. In general, Tg does not exceed 200 ° C. due to restrictions on raw material monomers.

  As the monomer constituting the vinyl polymer (A), various vinyl unsaturated compounds having radical polymerizability can be used, for example, (meth) acrylic acid compounds, aromatic vinyl compounds, unsaturated compounds. Carboxylic acid, unsaturated acid anhydride, hydroxyl group-containing unsaturated compound, amino group-containing unsaturated compound, amide group-containing unsaturated compound, alkoxyl group-containing unsaturated compound, cyano group-containing unsaturated compound, nitrile group-containing unsaturated compound And maleimide compounds. These compounds may be used alone or in combination of two or more.

  Among these, it is preferable that the main component is a (meth) acrylic acid-based compound because appropriate compatibility can be obtained with respect to the acrylic pressure-sensitive adhesive polymer. The specific use amount of the (meth) acrylic acid compound is preferably in the range of 10% by mass to 100% by mass. More preferably, it is the range of 30 mass% or more and 95 mass% or less, More preferably, it is the range of 50 mass% or more and 90 mass% or less.

  Examples of the (meth) acrylic acid compound include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, and n-butyl (meth) acrylate. , Isobutyl (meth) acrylate, tert-butyl (meth) acrylate, amyl (meth) acrylate, n-hexyl (meth) acrylate, n-octyl (meth) acrylate, ethylhexyl (meth) acrylate, ( (Meth) acrylic acid alkyl esters such as (meth) acrylic acid n-dodecyl, (meth) acrylic acid n-octadecyl; (meth) acrylic acid cyclohexyl, (meth) acrylic acid methylcyclohexyl, (meth) acrylic acid tert-butyl Cyclohexyl, cyclododecyl (meth) acrylate, (meth) acrylic acid Aliphatic vinyl monomers such as bornyl, adamantyl (meth) acrylate, dicyclopentenyl (meth) acrylate, dicyclopentanyl (meth) acrylate; phenyl (meth) acrylate, (meth) acrylic acid An aromatic ring-based vinyl polymer such as benzyl may be mentioned. These compounds may be used alone or in combination of two or more.

  Among these, (meth) acrylic acid can be set at a relatively high Tg, has a high effect of suppressing the lifting and peeling of the pressure-sensitive adhesive sheet, and has good adhesion to an olefinic adherend. It is preferable to use an aliphatic cyclic vinyl monomer such as isobornyl, dicyclopentanyl (meth) acrylate, cyclohexyl (meth) acrylate, and adamantyl (meth) acrylate. The specific use amount of the aliphatic cyclic vinyl monomer is preferably in the range of 10% by mass to 90% by mass and more preferably 20% by mass to 80% by mass with respect to all the constituent monomers of the vinyl polymer (A). % Or less is more preferable, and 30 mass% or more and 70 mass% or less are further more preferable.

  Examples of the aromatic vinyl compound include styrene, α-methyl styrene, o-methyl styrene, p-methyl styrene, vinyl toluene, β-methyl styrene, ethyl styrene, p-tert-butyl styrene, vinyl xylene, vinyl naphthalene, and the like. Is mentioned. These compounds may be used alone or in combination of two or more. The specific use amount of the aromatic vinyl compound is preferably in the range of 1% by mass to 40% by mass and more preferably 5% by mass to 30% by mass with respect to all the constituent monomers of the vinyl polymer (A). Preferably, 5 mass% or more and 20 mass% or less are more preferable.

  Examples of unsaturated carboxylic acids include (meth) acrylic acid, ethacrylic acid, maleic acid, fumaric acid, itaconic acid, crotonic acid, citraconic acid, cinnamic acid, and monoalkyl esters of unsaturated dicarboxylic acid (maleic acid). , Fumaric acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, monoalkyl esters such as citraconic anhydride) and the like. These compounds may be used alone or in combination of two or more.

  Examples of the unsaturated acid anhydride include maleic anhydride, itaconic anhydride, citraconic anhydride, and the like. These compounds may be used alone or in combination of two or more.

  Examples of the hydroxyl group-containing unsaturated compound include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, and 2-hydroxybutyl (meth) acrylate. , Mono (meth) acrylates of polyalkylene glycols such as 3-hydroxybutyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol, polypropylene glycol, p-hydroxystyrene, m-hydroxystyrene O-hydroxystyrene, p-isopropenylphenol, m-isopropenylphenol, o-isopropenylphenol and the like. These compounds may be used alone or in combination of two or more.

  Examples of the amino group-containing unsaturated compound include dimethylaminomethyl (meth) acrylate, diethylaminomethyl (meth) acrylate, 2-dimethylaminoethyl (meth) acrylate, 2-diethylaminoethyl (meth) acrylate, ( 2- (di-n-propylamino) ethyl (meth) acrylate, 2-dimethylaminopropyl (meth) acrylate, 2-diethylaminopropyl (meth) acrylate, 2- (di-n-propyl) (meth) acrylate Amino) propyl, 3-dimethylaminopropyl (meth) acrylate, 3-diethylaminopropyl (meth) acrylate, 3- (di-n-propylamino) propyl (meth) acrylate, and the like. These compounds may be used alone or in combination of two or more.

  Examples of the amide group-containing unsaturated compound include (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N-methylol (meth) acrylamide and the like. These compounds may be used alone or in combination of two or more.

  Examples of the alkoxyl group-containing unsaturated compound include 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, 2- (n-propoxy) ethyl (meth) acrylate, and (meth) acrylic acid. 2- (n-butoxy) ethyl, 3-methoxypropyl (meth) acrylate, 3-ethoxypropyl (meth) acrylate, 2- (n-propoxy) propyl (meth) acrylate, 2- (meth) acrylic acid 2- (N-butoxy) propyl and the like can be mentioned. These compounds may be used alone or in combination of two or more.

  Examples of the cyano group-containing unsaturated compound include cyanomethyl (meth) acrylate, 1-cyanoethyl (meth) acrylate, 2-cyanoethyl (meth) acrylate, 1-cyanopropyl (meth) acrylate, and (meth) acrylic. 2-cyanopropyl acid, 3-cyanopropyl (meth) acrylate, 4-cyanobutyl (meth) acrylate, 6-cyanohexyl (meth) acrylate, 2-ethyl-6-cyanohexyl (meth) acrylate, ( And (meth) acrylic acid 8-cyanooctyl. These compounds may be used alone or in combination of two or more.

  Examples of the nitrile group-containing unsaturated compound include (meth) acrylonitrile, ethacrylonitrile, α-ethylacrylonitrile, α-isopropylacrylonitrile, α-chloroacrylonitrile, α-fluoroacrylonitrile and the like. These compounds may be used alone or in combination of two or more.

  Examples of maleimide compounds include maleimide, N-methylmaleimide, N-isopropylmaleimide, N-butylmaleimide, N-dodecylmaleimide, N-cyclohexylmaleimide, N-phenylmaleimide, N- (2-methylphenyl) maleimide, Examples thereof include N- (4-methylphenyl) maleimide, N- (2,6-dimethylphenyl) maleimide, N- (2,6-diethylphenyl) maleimide, N-benzylmaleimide, N-naphthylmaleimide and the like. These compounds may be used alone or in combination of two or more.

  In addition to the above compounds, dialkyl esters of unsaturated dicarboxylic acids, vinyl ester compounds, vinyl ether compounds and the like can also be used. Examples of the dialkyl ester of unsaturated dicarboxylic acid include dialkyl esters such as maleic acid, fumaric acid, itaconic acid, citraconic acid, maleic anhydride, itaconic anhydride, and citraconic anhydride. Examples of the vinyl ester compound include methylene aliphatic monocarboxylic acid ester, vinyl acetate, vinyl propionate, vinyl pivalate, vinyl butyrate, vinyl benzoate, vinyl formate, and vinyl cinnamate. Examples of the vinyl ether compound include vinyl methyl ether, vinyl ethyl ether, vinyl n-butyl ether, vinyl isobutyl ether, vinyl phenyl ether, vinyl cyclohexyl ether, and the like.

  The number average molecular weight (Mn) of the vinyl polymer (A) can be 500 or more and 10,000 or less. Preferably they are 500 or more and 7,000 or less, More preferably, they are 1,000 or more and 5,000 or less. When Mn exceeds 10,000, the compatibility with the acrylic adhesive polymer (B) is deteriorated. On the other hand, in order to produce a polymer having Mn of less than 500, there are problems such as the necessity of using a large amount of a polymerization initiator and a chain transfer agent, and a decrease in productivity.

  In addition, the ratio (Mw / Mn) between the weight average molecular weight (Mw) and the above (Mn) is preferably 3.0 or less from the viewpoint that good adhesive strength is easily obtained. More preferably, it is 2.5 or less, More preferably, it is 2.0 or less, More preferably, it is 1.8 or less. In addition, the weight average molecular weight Mw and the number average molecular weight Mn are standard polystyrene conversion values obtained using gel permeation chromatography (GPC).

  The vinyl polymer (A) is not particularly limited with respect to its production method, but can be easily obtained by polymerizing the above monomers by employing a known radical polymerization method such as a solution polymerization method, for example. . In the case of the solution polymerization method, an organic solvent and a vinyl monomer raw material are charged into a reactor, a thermal polymerization initiator such as an organic peroxide or an azo compound is added, and the mixture is heated to 50 to 300 ° C. for copolymerization. As a result, the intended vinyl polymer can be obtained. The vinyl polymer may be used as a solution dissolved in an organic solvent, or may be used by distilling off the solvent by heating under reduced pressure.

  The charging method of each raw material including the monomer may be batch initial batch charging in which all raw materials are charged at once, or semi-continuous charging in which at least one raw material is continuously fed into the reactor. A continuous polymerization method in which the raw materials are continuously supplied and the product resin is continuously withdrawn from the reactor may be used.

  As the organic solvent used in the solution polymerization method, organic hydrocarbon compounds are suitable, cyclic ethers such as tetrahydrofuran and dioxane, aromatic hydrocarbon compounds such as benzene, toluene and xylene, ethyl acetate and butyl acetate and the like. Examples include esters, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, and alcohols such as methyl orthoformate, methyl orthoacetate, methanol, ethanol, and isopropanol. One or more of these can be used. Among these organic solvents, ethyl acetate, butyl acetate, acetone, and methyl ethyl ketone, which have a relatively low boiling point so as to dissolve the vinyl polymer well and facilitate purification, are preferable.

  The initiator used in the present specification can be an azo compound, an organic peroxide, an inorganic peroxide, or the like, but is not particularly limited. You may use the redox type polymerization initiator which consists of a well-known oxidizing agent and a reducing agent. Moreover, a well-known chain transfer agent can also be used together.

  Examples of the azo compound include 2,2′-azobis (isobutyronitrile), 1,1-azobis (cyclohexane-1-carbonitrile), azocumene, and 2,2′-azobis (2-methylbutyronitrile). ), 2,2′-azobisdimethylvaleronitrile, 4,4′-azobis (4-cyanovaleric acid), 2- (tert-butylazo) -2-cyanopropane, 2,2′-azobis (2,4 , 4-trimethylpentane), 2,2′-azobis (2-methylpropane), dimethyl 2,2′-azobis (2-methylpropionate), and the like.

  Examples of the organic peroxide include cyclohexanone peroxide, 3,3,5-trimethylcyclohexanone peroxide, methylcyclohexanone peroxide, 1,1-bis (tert-butylperoxy) -3,3,5-trimethylcyclohexane. 1,1-bis (tert-butylperoxy) cyclohexane, n-butyl-4,4-bis (tert-butylperoxy) valerate, cumene hydroperoxide, 2,5-dimethylhexane-2,5-di Hydroperoxide, 1,3-bis [(tert-butylperoxy) -m-isopropyl] benzene, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, diisopropylbenzene peroxide, tert -Butyl cumyl peroxide Decanoyl peroxide, lauroyl peroxide, benzoyl peroxide, 2,4-dichlorobenzoyl peroxide, bis (tert-butylcyclohexyl) peroxydicarbonate, tert-butylperoxybenzoate, 2,5-dimethyl-2,5 -Di (benzoyl peroxy) hexane etc. are mentioned.

  Examples of inorganic peroxides include potassium persulfate, sodium persulfate, and ammonium persulfate.

  Examples of redox type polymerization initiators include sodium sulfite, sodium thiosulfate, sodium formaldehyde sulfoxylate, ascorbic acid, ferrous sulfate and the like, potassium peroxodisulfate, hydrogen peroxide, tert-butyl hydroper What used an oxide etc. as an oxidizing agent can be used.

  The vinyl polymer (A) can also be obtained by continuous polymerization in a temperature range of 180 to 350 ° C. using a stirred tank reactor. In this polymerization method, since a relatively low molecular weight vinyl polymer can be obtained without substantially using a polymerization initiator or a chain transfer agent, a polymer having a high purity is obtained. However, it is preferable because it is advantageous. When the polymerization temperature is lower than 180 ° C., a polymerization initiator and a large amount of chain transfer agent are required for the polymerization reaction, and the obtained copolymer is easily colored and generates an unpleasant odor. On the other hand, when the polymerization temperature exceeds 350 ° C., a decomposition reaction is likely to occur during the polymerization reaction, and the resulting copolymer is colored. Therefore, the transparency of the pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition containing the polymerization reaction is increased. There is concern about the decline. Furthermore, according to such a polymerization method, a vinyl polymer having a small molecular weight distribution range can be obtained. The polymerization initiator may be optionally used, but is preferably used at about 1% by mass or less based on the total monomers.

[Acrylic adhesive polymer (B)]
The acrylic pressure-sensitive adhesive polymer (B) disclosed in this specification is a polymer containing (meth) acrylic acid esters as main structural units. The glass transition temperature (Tg) of the acrylic adhesive polymer (B) is preferably a polymer having adhesiveness in the range of −80 ° C. to 0 ° C., and in the range of −80 ° C. to −20 ° C. Is more preferable, and the range of −80 ° C. or higher and −30 ° C. or lower is more preferable. In addition, Preferably it is the range of -80 degreeC or more and -40 degrees C or less. When Tg is less than −80 ° C., the cohesive force of the obtained pressure-sensitive adhesive layer becomes insufficient, and the curved surface adhesion tends to deteriorate. When Tg exceeds 0 ° C., the step following ability and the adhesive strength at low temperatures may not be sufficient.

  Furthermore, the acrylic tacky polymer (B) preferably has a weight average molecular weight (Mw) of 100,000 or more from the viewpoint of exhibiting sufficient cohesive force and good adhesiveness. More preferably, it is 250,000 or more, More preferably, it is 400,000 or more. On the other hand, if the weight average molecular weight is too large, the step following property tends to be lowered, and the handling in production becomes difficult. Accordingly, the upper limit value is preferably 2,000,000 or less. More preferably, it is 1,500,000 or less, More preferably, it is 1,000,000 or less.

  As a monomer constituting the acrylic adhesive polymer (B), an alkyl (meth) acrylate having an alkyl group having 4 to 12 carbon atoms in that an acrylic copolymer having a low Tg and having an adhesive property is obtained. Examples thereof include esters and alkoxyalkyl (meth) acrylates having a C2-C12 alkoxyalkyl group, and one or more of these can be used.

  Examples of the (meth) acrylic acid alkyl ester having an alkyl group having 4 to 12 carbon atoms include n-butyl (meth) acrylate, isobutyl (meth) acrylate, n-hexyl (meth) acrylate, (meth) N-octyl acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, (meth) Examples of preferred monomers include n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, (meth ) N-nonyl acrylate, isononyl (meth) acrylate, and the like.

  Examples of the alkoxyalkyl (meth) acrylate having an alkoxyalkyl group having 2 to 12 carbon atoms include methoxymethyl (meth) acrylate, ethoxymethyl (meth) acrylate, butoxymethyl (meth) acrylate, (meth) Examples include methoxyethyl acrylate, ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, methoxybutyl (meth) acrylate, ethoxybutyl (meth) acrylate, butoxybutyl (meth) acrylate, and the like.

  The amount of (meth) acrylic acid alkyl ester having 4 to 12 carbon atoms and / or (meth) acrylic acid alkoxyalkyl having 2 to 12 carbon atoms is the total amount of acrylic copolymer. 30 mass% or more and 100 mass% or less are preferable on the basis of a constituent monomer, and 50 mass% or more and 99 mass% or less are still more preferable. When the amount is less than 30% by mass, the adhesive strength, initial adhesive strength (tack), low-temperature tackiness, and the like of the obtained adhesive composition are insufficient.

  Among the above, alkoxyalkyl (meth) acrylate is more preferable in that the vinyl polymer (A) is easily segregated to the surface layer in the pressure-sensitive adhesive layer while exhibiting good pressure-sensitive adhesive performance. The amount of (meth) acrylic acid alkoxyalkyl ester used is preferably 40% by mass or more, more preferably 45% by mass or more, and further preferably 50% by mass or more. Moreover, Preferably it is 60 mass% or more, More preferably, it is 70 mass% or more, More preferably, it is 80 mass% or more, More preferably, it is 85 mass% or more. Moreover, Preferably it is 90 mass% or more, More preferably, it is 92 mass% or more, More preferably, it is 95 mass% or more. In addition, the upper limit of the usage-amount of (meth) acrylic-acid alkoxyalkylester is 100 mass%.

  In addition to the above (meth) acrylic acid alkyl ester and (meth) acrylic acid alkoxyalkyl ester, the acrylic pressure-sensitive adhesive polymer (B) can be copolymerized with other monomers as long as the adhesiveness is not impaired. The body can be used.

  Examples of other vinyl monomers include α, β-ethylenically unsaturated carboxylic acid monomers such as (meth) acrylic acid, itaconic acid, maleic acid and fumaric acid; styrene, α-methylstyrene, vinyl Aromatic vinyl monomers such as toluene; cyclohexyl (meth) acrylate, methyl cyclohexyl (meth) acrylate, tert-butylcyclohexyl (meth) acrylate, cyclododecyl (meth) acrylate, isobornyl (meth) acrylate Aliphatic cyclic vinyl monomers such as itaconic acid monoethyl ester, fumaric acid monobutyl ester and other monoalkyl esters of unsaturated dicarboxylic acids; (meth) acrylic acid 2-hydroxyethyl, (meth) acrylic acid 3- Hydroxypropyl, 4-hydroxybutyl (meth) acrylate, polyethylene glycol Hydroxyl group-containing monomers such as (meth) acrylate, polypropylene glycol (meth) acrylate and polyethylene-polypropylene glycol mono (meth) acrylate; ethylene such as acrylamide, N-methylolacrylamide, N-methoxymethylacrylamide, N-methoxybutylacrylamide Unsaturated carboxylic acid amides and N-substituted compounds; unsaturated alcohols such as allyl alcohol; (meth) acrylonitrile, vinyl acetate, glycidyl (meth) acrylate, diacetone acrylamide, etc., and one of these or Two or more types can be used.

  In addition, a polyfunctional polymerizable monomer having two or more polymerizable functional groups such as a (meth) acryloyl group and an alkenyl group in the molecule may be used.

  Polyfunctional (meth) acrylate compounds include ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, polyethylene glycol di (meth) acrylate, polypropylene glycol di ( Di (meth) acrylates of dihydric alcohols such as (meth) acrylate; trimethylolpropane tri (meth) acrylate, trimethylolpropane ethylene oxide modified tri (meth) acrylate, glycerin tri (meth) acrylate, pentaerythritol tri ( Poly (meth) acrylates such as tri (meth) acrylates and tetra (meth) acrylates of trihydric or higher polyhydric alcohols such as (meth) acrylates and pentaerythritol tetra (meth) acrylates Mention may be made of the rate, and the like.

  Examples of polyfunctional alkenyl compounds include polyfunctional allyl ether compounds such as trimethylolpropane diallyl ether, pentaerythritol diallyl ether, pentaerythritol triallyl ether, tetraallyloxyethane, and polyallyl saccharose; polyfunctional allyl compounds such as diallyl phthalate; methylene Examples thereof include bisamides such as bisacrylamide and hydroxyethylenebisacrylamide; polyfunctional vinyl compounds such as divinylbenzene.

  Examples of the compound having both (meth) acryloyl group and alkenyl group include allyl (meth) acrylate, isopropenyl (meth) acrylate, butenyl (meth) acrylate, pentenyl (meth) acrylate, (meth) acrylic acid. 2- (2-vinyloxyethoxy) ethyl and the like can be mentioned.

  The acrylic adhesive polymer (B) can also be obtained by a known radical polymerization method such as a solution polymerization method, a suspension polymerization method, or an emulsion polymerization method.

[Adhesive composition]
This adhesive composition can contain a vinyl polymer (A) and an acrylic adhesive polymer (B). The vinyl polymer (A) has appropriate compatibility with the acrylic adhesive polymer (B). For this reason, the pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition containing them exhibits good transparency, and the vinyl polymer (A) partially segregates in the pressure-sensitive adhesive layer, and the vinyl polymer (A ) May be higher than other portions.

  Thus, when it takes the structure where the density | concentration of the vinyl polymer (A) in the surface layer of an adhesive layer becomes higher than others, it has sufficient curved surface adhesiveness. Furthermore, since the pressure-sensitive adhesive layer in the vicinity of the adhesive interface has a relatively high Tg, it can exhibit good adhesion even under high temperature conditions. In addition, the pressure-sensitive adhesive sheet can be prevented from floating or peeling off due to outgas generated from the adherend. In addition to the segregation behavior of the vinyl polymer (A) in the present pressure-sensitive adhesive composition, the difference in Tg between the surface layer of the pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer as described below is the difference between the vinyl polymer (B) and the acrylic polymer (B). In addition to the blending ratio of A), the monomer composition (polarity) and molecular weight of the vinyl polymer (A), it can be adjusted by appropriately setting Tg, Mw / Mn, and the like.

  This pressure-sensitive adhesive composition can contain 0.5 parts by mass or more and 60 parts by mass or less of the vinyl polymer (A) in terms of solid content with respect to 100 parts by mass of the acrylic adhesive polymer (B). The minimum of preferable content is 1 mass part or more, More preferably, it is 3 mass parts or more, More preferably, it is 4 mass parts or more. Moreover, the upper limit of preferable content is 50 mass parts or less, More preferably, it is 40 mass parts or less, More preferably, it is 30 mass parts or less. Moreover, the range of preferable content is 1 to 40 mass parts, More preferably, it is 3 to 30 mass parts. When the amount of the vinyl polymer (A) used is less than 0.5 parts by mass, the segregation of the vinyl polymer (A) in the pressure-sensitive adhesive layer is insufficient, and particularly satisfactory results cannot be obtained in high-temperature adhesiveness. There is. On the other hand, when it exceeds 60 parts by mass, the vinyl polymer (A) is excessively segregated, and as a result, the step following property and the adhesiveness including tack may be insufficient. Moreover, it may phase-separate with an acrylic adhesive polymer (B), and the transparency of an adhesive layer may fall.

[Crosslinking agent]
The pressure-sensitive adhesive composition can contain a crosslinking agent. The cross-linking agent is not necessarily required, but addition of the cross-linking agent is considered depending on the intended adhesive properties and the form of the present pressure-sensitive adhesive composition, for example, whether it is an emulsion form or a solution form. By containing a cross-linking agent, the cohesive strength and adhesive strength of the pressure-sensitive adhesive layer obtained from the present pressure-sensitive adhesive composition are adjusted, and further, adhesion at high temperatures and high humidity and adhesion to curved surfaces are imparted. be able to. Crosslinking agents include glycidyl compounds having two or more glycidyl groups, isocyanate compounds having two or more isocyanate groups, aziridine compounds having two or more aziridinyl groups, oxazoline compounds having an oxazoline group, metal chelate compounds, butylated melamine compounds Etc. Among these, it is preferable to use an aziridine compound, a glycidyl compound, and an isocyanate compound.

  Examples of the aziridine compound include 1,6-bis (1-aziridinylcarbonylamino) hexane, 1,1 ′-(methylene-di-p-phenylene) bis-3,3-aziridylurea, 1,1 ′. -(Hexamethylene) bis-3,3-aziridylurea, ethylenebis- (2-aziridinylpropionate), tris (1-aziridinyl) phosphine oxide, 2,4,6-triaziridinyl-1,3,5 -Triazine, trimethylolpropane-tris- (2-aziridinylpropionate), etc. are mentioned.

  Examples of the glycidyl compound include ethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, glycerin diglycidyl ether, neopentyl glycol diglycidyl ether, and 1,6-hexanediol diester. Such as glycidyl ether, tetraglycidyl xylenediamine, 1,3-bis (N, N-diglycidylaminomethyl) cyclohexane, trimethylolpropane polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, etc. A polyfunctional glycidyl compound is mentioned.

  As the isocyanate compound, a compound having two or more isocyanate groups is preferably used. As the isocyanate compound, aromatic, aliphatic, and alicyclic isocyanate compounds, and modified products (such as prepolymers) of these isocyanate compounds can be used.

  Examples of the aromatic isocyanate include diphenylmethane diisocyanate (MDI), crude diphenylmethane diisocyanate, tolylene diisocyanate, naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), xylene diisocyanate (XDI), and tetramethylxylylene diisocyanate (TMXDI). And tolidine diisocyanate (TODI). Examples of the aliphatic isocyanate include hexamethylene diisocyanate (HDI), lysine diisocyanate (LDI), and lysine triisocyanate (LTI). Examples of the alicyclic isocyanate include isophorone diisocyanate (IPDI), cyclohexyl diisocyanate (CHDI), hydrogenated XDI (H6XDI), and hydrogenated MDI (H12MDI). The modified isocyanate includes urethane modified products, dimers, trimers, carbodiimide modified products, allophanate modified products, burette modified products, urea modified products, isocyanurate modified products, oxazolidone modified products, isocyanates. Examples thereof include base end prepolymers.

  The content of the crosslinking agent is preferably 0.01 parts by mass or more and 10 parts by mass or less with respect to 100 parts by mass of the acrylic adhesive polymer (B). A more preferable lower limit is 0.03 parts by mass or more, and further preferably 0.05 parts by mass or more. Moreover, a more preferable upper limit is 5 parts by mass or less, and further preferably 2 parts by mass or less. A more preferable range is 0.03 parts by mass or more and 5 parts by mass or less, and a further preferable range is 0.05 parts by mass or more and 2 parts by mass or less.

[Tg of first pressure-sensitive adhesive layer formed from the present pressure-sensitive adhesive composition (first Tg)]
The glass transition temperature (Tg) of the entire pressure-sensitive adhesive layer formed from the present pressure-sensitive adhesive composition, that is, the first Tg can be in the range of −80 ° C. or higher and 10 ° C. or lower. A preferable lower limit is −70 ° C. or higher, and more preferably −60 ° C. or higher. Moreover, a preferable upper limit is 0 degrees C or less, More preferably, it is -10 degrees C or less, More preferably, it is -20 degrees C or less. A preferred range is from -70 ° C to -20 ° C. When the first Tg is less than −80 ° C., the cohesive force of the resulting pressure-sensitive adhesive layer tends to be insufficient, and the curved surface adhesion and the like tend to be deteriorated. The adhesive strength below may not be sufficient. The Tg of the present pressure-sensitive adhesive composition can be obtained by DSC using a temperature increase rate of 10 ° C./min and a nitrogen atmosphere as a measurement atmosphere.

[Tg calculated from the composition of the surface layer portion of the pressure-sensitive adhesive layer (second Tg)]
The second Tg of the pressure-sensitive adhesive composition, that is, the pressure-sensitive adhesive layer obtained by X-ray photoelectron spectroscopy when the pressure-sensitive adhesive composition is applied to a separator and dried to obtain a pressure-sensitive adhesive layer. Tg calculated from the composition of the surface layer part is obtained by calculation from the composition ratio of the vinyl polymer (A) and the acrylic adhesive polymer (B) obtained from X-ray photoelectron spectroscopy (XPS). It can be understood as Tg of the composition that forms the surface layer from the surface of the layer to the depth of about 5 nm. The details of the measurement method can follow the operations described in the examples described later.

  The second Tg is not particularly limited, but is preferably 0 ° C. or higher. When the second Tg is 0 ° C. or more, a Tg difference described below can be easily obtained. As a result, the high-temperature adhesiveness and durability of the adherend can be secured together with the curved surface adhesiveness. The second Tg is more preferably 10 ° C or higher, still more preferably 25 ° C or higher, and still more preferably 40 ° C or higher. In addition, 2nd Tg can be suitably adjusted with Tg, a compounding ratio, etc. of a vinyl polymer (A).

[Difference between Tg (first Tg) of the entire pressure-sensitive adhesive layer and Tg (second Tg) calculated from the composition of the surface layer portion of the pressure-sensitive adhesive layer]
In the present pressure-sensitive adhesive composition, the second Tg (Tg calculated from the composition of the surface layer portion of the pressure-sensitive adhesive layer) is 30 ° C. or more higher than the first Tg (Tg of the whole pressure-sensitive adhesive layer). Is preferred. According to the pressure-sensitive adhesive layer having such a Tg composition, the higher the temperature of the pressure-sensitive adhesive layer of the conventional general pressure-sensitive adhesive, the lower the adhesiveness. Strength) and high curved surface adhesion.

  Furthermore, even when the second Tg is higher than the first Tg by 30 ° C. or more, even when a transparent plastic substrate such as polypropylene and polycarbonate is used as an adherend and exposed to high temperature and high humidity. In addition, floating and peeling at the adhesive interface with the pressure-sensitive adhesive layer due to bubbles (foaming) generated from a plastic substrate or the like are suppressed, and good durability (foaming resistance) is exhibited.

  The second Tg is preferably higher than the first Tg by 40 ° C. or more, more preferably 50 ° C. or more, more preferably 60 ° C. or more, still more preferably 65 ° C. or more, and 70 ° C. or more. Even more preferred. The upper limit of the height of the second Tg relative to the first Tg is not particularly limited, but is 230 ° C. from the values that the first Tg and the second Tg can take, and is generally 200 ° C. It is as follows.

[Mass fraction (A / A + B) of vinyl polymer (A) with respect to the total mass of vinyl polymer (A) and acrylic adhesive polymer (B) in the surface layer portion of the pressure-sensitive adhesive layer]
In measuring the second Tg, composition analysis by X-ray photoelectron spectroscopic analysis of the surface layer of the pressure-sensitive adhesive layer is performed. At this time, the mass fraction of the vinyl polymer (A) in the surface layer can be obtained. This mass fraction can be used as an index of the segregation state of the vinyl polymer (A) in the surface layer portion of the pressure-sensitive adhesive layer.

  For example, the mass fraction is preferably 55% or more and 95% or less. Within this range, segregation to the surface layer portion of the vinyl polymer (A) occurs, and curved surface adhesion and durability can be obtained even under high temperature and high humidity. More preferably, it is 60% or more, still more preferably 65% or more, still more preferably 70% or more, still more preferably 75% or more, and still more preferably 80% or more. Further, the mass fraction is preferably 90% or less, and more preferably 85% or less.

[Adhesion (peel strength)]
This pressure-sensitive adhesive composition is a polypropylene (PP) plate at 85 ° C. and a peeling speed of 300 mm / min for a pressure-sensitive adhesive sheet comprising a pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition and having a thickness of 50 μm on a 100 μm-thick polyethylene terephthalate film substrate. It is preferable that the adhesive strength with respect to is 3.0 N / 25 mm or more. By setting the adhesive strength under a high temperature condition of 85 ° C. to 3.0 N / 25 mm or more, the adhesive strength under a high temperature and high humidity condition is sufficiently high with respect to the PP plate. Prevention and good curved surface adhesion can be ensured. More preferably, it is 3.5 N / 25mm or more, More preferably, it is 4.0 N / 25mm or more.

  Here, in producing the pressure-sensitive adhesive layer (pressure-sensitive adhesive sheet), the pressure-sensitive adhesive composition is directly applied to a polyester film substrate and dried to obtain a pressure-sensitive adhesive sheet, or once applied to a release paper or the like. Any method of transferring to a polyester film substrate after processing may be employed. Although drying may be performed at room temperature, from the viewpoint of productivity and the like, the drying is usually performed for several seconds to several tens of minutes under a heating condition of 40 to 150 ° C. using a dryer. The method is common. More specifically, after applying this pressure-sensitive adhesive composition to a PET film separator so that the thickness after drying is 50 μm, it is necessary to remove ethyl acetate by drying at 80 ° C. for 4 minutes. In accordance with the above, a 38 μm thick PET separator having a peeling force different from that of the separator is bonded, and left to stand at 40 ° C. for 5 days. Can be obtained.

  In measuring the peel strength, the adhesive film sample was further transferred to an easily adhered PET film (100 μm) to obtain an evaluation adhesive sheet, which was applied to a PP plate (manufactured by Sumitomo Noblen, Nobrene MHB, 2 mm thickness). After sticking the pressure-sensitive adhesive sheet and pressing for 20 minutes under a condition of 0.5 MPa and 50 ° C. using a tabletop pressure degassing apparatus TBR-200 (manufactured by Chiyoda Electric Industry Co., Ltd.), for example, a tensile tester with a thermostatic bath Using a graph R type (manufactured by Toyo Seiki Co., Ltd.) etc., the 180 ° peel strength of the pressure sensitive adhesive sheet is measured according to JISZ-0237 “Testing method of pressure sensitive adhesive tape / pressure sensitive adhesive sheet” at 23 ° C. or 85 ° C. It can be strength.

  The pressure-sensitive adhesive layer of the present pressure-sensitive adhesive composition has high adhesiveness at high temperature to polypropylene as an adherend, but these characteristics are based on the Tg composition (distribution) of the pressure-sensitive adhesive layer. Therefore, high temperature adhesiveness can be provided regardless of the type of material of the adherend.

[Transparency (haze value)]
A haze value can be used as an index for evaluating the transparency of the pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition. As described above, the pressure-sensitive adhesive layer obtained from the present pressure-sensitive adhesive composition has an appropriate compatibility with the acrylic pressure-sensitive adhesive polymer (B). Shows good transparency.

  The haze value can be evaluated by the following method, for example. That is, after peeling one separator from the adhesive film sample by this adhesive composition, transferring to a glass plate, and peeling the other separator, it left still at 23 degreeC and 50% RH conditions for one day, and used a haze meter. Use to measure haze value. It can be evaluated that the lower the haze value, the better the transparency. A preferred haze value is 2.0 or less. When the haze value is 2.0 or less, it can be said that there is certain preferable transparency. A more preferable haze value is 1.6 or less, still more preferably 1.4 or less, and still more preferably 1.0 or less.

(Foam resistance)
The pressure-sensitive adhesive layer obtained by the present pressure-sensitive adhesive composition has a relatively high Tg of the pressure-sensitive adhesive layer surface layer, and is excellent in adhesiveness at the interface with the adherend. For this reason, even if gas generate | occur | produces from a to-be-adhered body, the floating and peeling of an adhesive layer are suppressed.

  For example, the foam resistance can be evaluated by the following method. That is, a laminate in which an adhesive film sample having a thickness of 100 μm is pasted on one surface of an adhesive film sample made of the present adhesive composition, and an adherend (PP plate or polycarbonate (PC) plate) is pasted on the other surface. After the body was prepared and subjected to pressure treatment at 50 ° C., 0.5 MPa, 20 minutes, the laminate was subjected to a load for 24 hours in a 60 ° C./90% constant temperature and humidity chamber, and the appearance after the load was observed, The ratio of the foamed area to the total area is obtained as appropriate. For example, the resistance to foaming is evaluated based on whether or not the appearance changes and the foaming area is 10% of the whole.

  In addition to the vinyl polymer (A) and the acrylic adhesive polymer (B) as a tackifier, this pressure-sensitive adhesive composition is optionally provided with a tackifier, a plasticizer, an antioxidant, an ultraviolet absorber, aging. It can also be set as the composition containing additives, such as an inhibitor, a flame retardant, an antifungal agent, a silane coupling agent, a filler, and a coloring agent.

  Tackifiers include rosin derivatives such as rosin ester, gum rosin, tall oil rosin, hydrogenated rosin ester, maleated rosin, disproportionated rosin ester; terpene phenol resin, α-pinene, β-pinene, limonene, etc. (Hydrogenated) petroleum resin; coumarone-indene resin; hydrogenated aromatic copolymer; styrene resin; phenol resin; xylene resin; (meth) acrylic polymer.

  Examples of the plasticizer include di-n-butyl phthalate, di-n-octyl phthalate, bis (2-ethylhexyl) phthalate, di-n-decyl phthalate, diisodecyl phthalate and the like; bis (2-ethylhexyl) adipate, di-n Adipic acid esters such as octyl adipate; Sebacic acid esters such as bis (2-ethylhexyl) sebacate; di-n-butyl sebacate; Azelaic acid esters such as bis (2-ethylhexyl) azelate; Paraffins such as chlorinated paraffin Glycols such as polypropylene glycol; epoxy-modified vegetable oils such as epoxidized soybean oil and epoxidized linseed oil; phosphate esters such as trioctyl phosphate and triphenyl phosphate; phosphite esters such as triphenyl phosphite; ; Ester oligomers such as esterified products of adipic acid and 1,3-butylene glycol; low molecular weight polymers such as low molecular weight polybutene, low molecular weight polyisobutylene and low molecular weight polyisoprene; oils such as process oil and naphthenic oil Etc.

  Antioxidants include 2,6-di-tert-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-tert-butyl-4-ethylphenol, stearyl-β- (3,5-di- -Tert-butyl-4-hydroxyphenyl) propionate, 2,2'-methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-tert-butylphenol), 4, 4'-thiobis (3-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert-butylphenol), 3,9-bis [1,1-dimethyl-2- [β -(3-tert-Butyl-4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetra Oxaspiro [5.5] undecane, 1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5 -Di-tert-butyl-4-hydroxybenzyl) benzene, tetrakis- [methylene-3- (3 ', 5'-di-tert-butyl-4'-hydroxyphenyl) propionate] methane, bis [3,3' -Bis- (4'-hydroxy-3'-tert-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3 ', 5'-di-tert-butyl-4'-hydroxybenzyl) -Phenolic antioxidants such as -S-triazine-2,4,6- (1H, 3H, 5H) trione, tocopherols; dilauryl 3,3'-thiodipro Sulfur antioxidants such as onate, dimyristyl 3,3′-thiodipropionate, stearyl 3,3′-thiodipropionate; triphenyl phosphite, diphenylisodecyl phosphite, 4,4′-butylidene-bis (3-methyl-6-tert-butylphenylditridecyl) phosphite, cyclic neopentanetetraylbis (octadecyl phosphite), tris (nonylphenyl) phosphite, tris (monononylphenyl) phosphite, tris (di Nonylphenyl) phosphite, diisodecylpentaerythritol diphosphite, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (3,5-di-tert-butyl-4-hydroxybenzyl -9,10- Hydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-decyloxy-9,10-dihydro-9-oxa-10-phosphaphenanthrene, tris (2,4-di-tert-butylphenyl) phos Phyto, cyclic neopentanetetrayl bis (2,4-di-tert-butylphenyl) phosphite, cyclic neopentanetetrayl bis (2,6-di-tert-butyl-4-methylphenyl) phosphite, Examples thereof include phosphorus antioxidants such as 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite.

  Examples of UV absorbers include salicylic acid UV absorbers such as phenyl salicylate, p-tert-butylphenyl salicylate, p-octylphenyl salicylate; 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy- 4-octoxybenzophenone, 2-hydroxy-4-dodecyloxybenzophenone, 2,2′-dihydroxy-4-methoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2-hydroxy-4-methoxy Benzophenone ultraviolet absorbers such as -5-sulfobenzophenone and bis (2-methoxy-4-hydroxy-5-benzoylphenyl) methane; 2- (2'-hydroxy-5'-methylphenyl) benzotriazole, 2- ( 2 -Hydroxy-5'-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) benzotriazole, 2- (2'-hydroxy-3'-tert) -Butyl-5'-methylphenyl) -5-chlorobenzotriazole, 2- (2'-hydroxy-3 ', 5'-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2'- Hydroxy-3 ′, 5′-di-tert-amylphenyl) benzotriazole, 2- (2′-hydroxy-4′-octoxyphenyl) benzotriazole, 2- [2′-hydroxy-3 ′-(3 ″) , 4 ", 5", 6 "-tetrahydrophthalimidomethyl) -5'-methylphenyl] benzotriazole, 2,2-methylenebis [4 (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol], 2- (2′-hydroxy-5′-methacryloxyphenyl) -2H-benzotriazole, Benzotriazole ultraviolet absorbers such as 2,2′-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol]; 2-ethylhexyl- Cyanoacrylate ultraviolet absorbers such as 2-cyano-3,3′-diphenyl acrylate and ethyl-2-cyano-3,3′-diphenyl acrylate; nickel bis (octylphenyl) sulfide, [2,2′-thiobis ( 4-tert-octylphenolate)]-n-butylamine nickel, nickel complex-3,5-di-t Examples thereof include nickel-based ultraviolet stabilizers such as ert-butyl-4-hydroxybenzyl-phosphate monoethylate and nickel-dibutyldithiocarbamate.

  Anti-aging agents include poly (2,2,4-trimethyl-1,2-dihydroquinoline), 6-ethoxy-1,2-dihydro-2,2,4-trimethylquinoline, 1- (N-phenylamino) ) -Naphthalene, styrenated diphenylamine, dialkyldiphenylamine, N, N′-diphenyl-p-phenylenediamine, N-phenyl-N′-isopropyl-p-phenylenediamine, N, N′-di-2-naphthyl-p- Phenylenediamine, 2,6-di-tert-butyl-4-methylphenol, mono (α-methylbenzyl) phenol, di (α-methylbenzyl) phenol, tri (α-methylbenzyl) phenol, 2,2′- Methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4-ethyl-6- ert-butylphenol), 4,4′-butylidenebis (6-tert-butyl-3-methylphenol), 4,4′-thiobis (6-tert-butyl-3-methylphenol), 1,1-bis (4 -Hydroxyphenyl) cyclohexane, 2,5-di-tert-butylhydroquinone, 2,5-di-tert-amylhydroquinone, 2-mercaptobenzimidazole, zinc salt of 2-mercaptobenzimidazole, 2-mercaptomethylbenzimidazole, Examples include nickel dibutyldithiocarbamate, tris (nonylphenyl) phosphite, dilauryl thiodipropionate, distearyl thiodipropionate.

  Flame retardants include tetrabromobisphenol A, 2,2-bis (4-hydroxy-3,5-dibromophenyl) propane, hexabromobenzene, tris (2,3-dibromopropyl) isocyanurate, 2,2-bis Halogen flame retardants such as (4-hydroxyethoxy-3,5-dibromophenyl) propane, decabromodiphenyl oxide, halogen-containing polyphosphate; ammonium phosphate, tricresyl phosphate, triethyl phosphate, tris (β-chloroethyl) Phosphorus flame retardants such as phosphate, trischloroethyl phosphate, trisdichloropropyl phosphate, cresyl diphenyl phosphate, xylenyl diphenyl phosphate, acidic phosphate ester, nitrogen-containing phosphorus compound; red phosphorus, tin oxide, ammonium trioxide Inorganic flame retardants such as mon, zirconium hydroxide, barium metaborate, aluminum hydroxide, magnesium hydroxide; poly (dimethoxysiloxane), poly (diethoxysiloxane), poly (diphenoxysiloxane), poly (methoxyphenoxysiloxane) Siloxane flame retardants such as methyl silicate, ethyl silicate, and phenyl silicate.

  Examples of fungicides include benzimidazole, benzothiazole, trihaloallyl, triazole, organic nitrogen sulfur compounds and the like.

  As silane coupling agents, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-methacryloxypropyltrimethoxysilane, vinyltriacetoxysilane, γ-glycidoxypropyltrimethoxysilane, γ-glycidoxy Propyltriethoxysilane, β- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, γ-chloropropylmethoxysilane, vinyltrichlorosilane, γ-mercaptopropyltrimethoxysilane, γ-aminopropyltriethoxysilane, N-β (Aminoethyl) -γ-aminopropyltrimethoxysilane and the like can be mentioned.

  Examples of the filler include inorganic powder fillers such as calcium carbonate, titanium oxide, mica, and talc; and fibrous fillers such as glass fibers and organic reinforcing fibers.

  If this adhesive composition contains a vinyl polymer (A) and an acrylic adhesive polymer (B), there will be no special restriction | limiting in the form. For example, it may be used as a form of a solvent-type pressure-sensitive adhesive composition dissolved in an organic solvent such as ethyl acetate, or a form of an emulsion-type pressure-sensitive adhesive composition in which an acrylic pressure-sensitive adhesive polymer and a tackifier are dispersed in an aqueous medium. It may be used as In the case of a solution-type pressure-sensitive adhesive composition and an emulsion-type pressure-sensitive adhesive composition, the medium such as an organic solvent or water used is usually 20 to 80 parts by mass with respect to 100 parts by mass of the pressure-sensitive adhesive composition.

  When used as an emulsion-type pressure-sensitive adhesive, a stabilizer can be blended. This stabilizer is used for vinyl chloride such as cadmium stearate, zinc stearate, barium stearate, calcium stearate, lead dibutyltin dilaurate, tris (nonylphenyl) phosphite, triphenylphosphite, diphenylisodecylphosphite, etc. Stabilizer; di-n-octyltin bis (isooctylthioglycolate) salt, di-n-octyltin maleate polymer, di-n-octyltin dilaurate, di-n-octyltin maleate Ester salt, di-n-butyltin bismaleic acid ester salt, di-n-butyltin maleate polymer, di-n-butyltin bisoctylthioglycol ester salt, di-n-butyltin β-mercaptopropionate polymer, di -N-Butyl tin dilaure Di-n-methyltin bis (isooctyl mercaptoacetate) salt, poly (thiobis-n-butyltin sulfide), monooctyltin tris (isooctylthioglycolate), dibutyltin maleate, di-n-butyltin maleate ester・ Carboxylate and di-n-butyltin malate ester ・ Organic tin stabilizers such as mercaptides; tribasic lead sulfate, dibasic lead phosphite, basic lead sulfite, dibasic lead phthalate, silica Lead stabilizers such as lead acid, dibasic lead stearate, lead stearate; metal soap stabilizers such as cadmium soap, zinc soap, barium soap, lead soap, composite metal soap, calcium stearate Etc.

  In addition to the vinyl polymer (A) and the acrylic pressure-sensitive adhesive polymer (B), the present pressure-sensitive adhesive composition includes a monofunctional and / or polyfunctional (meth) acrylic acid monomer, and By using a composition containing a photopolymerization initiator or the like, the composition may be used as a so-called syrup-type photocurable pressure-sensitive adhesive composition that is cured by active energy rays such as ultraviolet rays.

  In the case of the photocurable pressure-sensitive adhesive composition, the composition may contain an organic solvent or the like, but is generally used as a solventless type containing no solvents.

  Monofunctional (meth) acrylic acid monomers include (meth) acrylic acid alkyl esters having an alkyl group having 1 to 12 carbon atoms; (meth) acrylic acid cyclohexyl, (meth) acrylic acid dicyclopentyl, (meta ) (Meth) acrylic acid esters having a cyclic structure such as isobornyl acrylate; hydroxyalkyl (meth) acrylates such as hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, hydroxybutyl (meth) acrylate Esters; (meth) acrylic acid and the like. These compounds may be used alone or in combination of two or more.

  Polyfunctional (meth) acrylic acid monomers include butanediol di (meth) acrylate, hexanediol di (meth) acrylate and other alkylene glycol di (meth) acrylates; triethylene glycol di (meth) acrylate Polyalkylene glycol di (meth) acrylates such as: trimethylolpropane tri (meth) acrylate and its ethylene oxide and / or propylene oxide modified products, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, etc. Can be mentioned. In addition, a polymer (macromonomer) having a (meth) acryloyl group such as polyurethane (meth) acrylate and polyisoprene-based (meth) acrylate can also be used. Specific examples of the polyisoprene-based (meth) acrylate include an esterified product of a maleic anhydride adduct of isoprene polymer and 2-hydroxyethyl methacrylate. These compounds may be used alone or in combination of two or more.

  Examples of the photopolymerization initiator include benzoin and its alkyl ethers, acetophenones, anthraquinones, thioxanthones, ketals, benzophenones, xanthones, acylphosphine oxides, α-diketones, and the like. Moreover, in order to improve the sensitivity by an active energy ray, a photosensitizer can also be used together. Examples of the photosensitizer include benzoic acid and amine photosensitizers. These can also be used in combination of two or more. As for the usage-amount of a photoinitiator and a photosensitizer, 0.01-10 mass parts is preferable with respect to 100 mass parts of monofunctional and / or polyfunctional (meth) acrylic-acid type monomers.

  Furthermore, this pressure-sensitive adhesive composition includes the vinyl polymer (A), a monofunctional and / or polyfunctional (meth) acrylic acid monomer, in addition to the photocurable pressure-sensitive adhesive composition described above. Moreover, it can be used also as a photocurable adhesive composition by a composition containing a photoinitiator. The said acrylic adhesive polymer (B) can be mixed with the said photocurable adhesive composition as needed.

[Production of pressure-sensitive adhesive composition]
If this adhesive composition contains a vinyl polymer (A) and an acrylic adhesive polymer (B) in the specified amount, there are no particular restrictions on the mixing method. For example, this pressure-sensitive adhesive composition may be obtained by mixing a vinyl polymer (A) and an acrylic pressure-sensitive adhesive polymer (B), or an acrylic pressure-sensitive adhesive polymer (B) in the presence of the vinyl polymer (A). ) May be polymerized to obtain the present pressure-sensitive adhesive composition.

  The present pressure-sensitive adhesive composition can be obtained by adjusting the Tg (first Tg) of the entire pressure-sensitive adhesive layer and the Tg (second Tg) of the surface of the pressure-sensitive adhesive layer when the pressure-sensitive adhesive layer is formed. That is, those skilled in the art will realize the adhesiveness of the pressure-sensitive adhesive layer to be finally obtained in order to realize the first Tg, the second Tg, and the temperature difference thereof. Based on the teaching, the present pressure-sensitive adhesive composition can be obtained by appropriately selecting and blending the vinyl polymer (A) and the acrylic pressure-sensitive adhesive polymer (B).

  The pressure-sensitive adhesive composition is prepared by, for example, dissolving a vinyl polymer (A) in a solvent such as ethyl acetate to prepare a polymer solution, and adding a polymer of an acrylic pressure-sensitive adhesive polymer (B) to the polymer solution. It can be produced by mixing the solution and, if necessary, mixing a crosslinking agent.

[Decorative film]
This pressure-sensitive adhesive composition can constitute a pressure-sensitive adhesive layer of a decorative film. A decorative film including a pressure-sensitive adhesive layer obtained from the pressure-sensitive adhesive composition can exhibit sufficient adhesiveness under high temperature and high humidity and on a curved surface.

  That is, the pressure-sensitive adhesive layer provided in the decorative film is a composition derived from the pressure-sensitive adhesive composition, the first Tg of the whole pressure-sensitive adhesive layer, the second Tg calculated from the composition of the surface layer portion of the pressure-sensitive adhesive layer, These temperature differences can be provided. More preferably, the aforementioned peel strength can be provided.

  In addition to the pressure-sensitive adhesive layer described above, the decorative film can include a decorative layer and a base material layer in this order.

  After the decorative film is decorated on the molded body, the base material layer is positioned in the outermost layer of the decorative molded body, which will be described later, and functions as a protective layer for the decorative molded body. The material which comprises a base material layer should just be a material which has a softness | flexibility, and a plastic is preferable. More preferably, it is a thermoplastic. The thermoplastic plastic is not particularly limited, and examples thereof include polyethylene terephthalate (PET) resin, acrylic resin, ABS resin, polycarbonate resin, polypropylene resin, and polyethylene resin. Among these, as a material used for the base material layer, a PET resin is preferable.

  The thickness of the base material layer is preferably 25 μm to 300 μm, more preferably 50 μm to 200 μm. When the thickness of the base material layer is within the above range, when the decorative molded body is produced by a vacuum forming method, the processability, shape followability, and handleability are improved.

  A decoration layer is a layer provided in order to provide the designability of a decoration film, and forms patterns, such as a text, a figure, a pattern, and a trademark, by printing etc. The pattern formed on the decorative layer can be formed by a known printing method such as gravure printing with printing ink, offset printing, silk screen printing, transfer printing from a transfer sheet, sublimation transfer printing, and ink jet printing.

  The thickness of the decoration layer is preferably 5 to 40 μm, more preferably 5 to 30 μm. When the thickness of the decorative layer is within the above range, a sufficient thickness can be secured to express a complicated design such as gradation.

  The decorative film disclosed in the present specification can further include a release layer. The release layer prevents unintended adhesion, and is peeled off when the decorative film is bonded to the molded body. The material constituting the release layer is not particularly limited. For example, polyester films such as polyethylene terephthalate, polybutylene terephthalate and polyethylene naphthalate, plastic films such as polyolefin films such as polypropylene and polyethylene; glassine paper, kraft paper, clay coated paper A material such as paper can be used. These thicknesses can be about 10 to 400 μm.

[Decorated molded body]
This specification can provide a decoration molded object (henceforth this decoration molded object) provided with the decoration film indicated by this specification. Since this decorative molded body includes a decorative film provided with a pressure-sensitive adhesive layer obtained from the present pressure-sensitive adhesive composition, the decorative molded body does not float or peel even when exposed to high temperature and high humidity, and has excellent durability. .

  The molded body to which the decorative film is bonded is not particularly limited, and may be an article or the like that can bond a decorative film such as a home appliance, an automobile interior, or a miscellaneous product.

  For the production of the decorative molded body, a vacuum molding method or an injection molding method can be used. In the vacuum forming method, the decorative film is stretched while being softened by heating, the space on the molded body side of the decorative film is decompressed, and the space on the opposite side is pressurized as necessary, thereby forming the decorative film into a molded body. Adhering while forming along the surface shape. In the injection molding method, the present decorative film is set in a mold cavity of an injection molding machine, and the present decorative film is bonded along the surface shape of the molded body by performing injection molding. By these methods, this decorative molded body can be obtained.

  Hereinafter, specific examples embodying the disclosure of this specification will be shown. However, the disclosure of the present specification is not limited to the following specific examples. In the following description, “part” means part by mass, and “%” means mass%.

  Various analyzes in this specification were performed by the methods described below.

<Solid content>
About 1 g of the measurement sample was weighed (a), then the residue after drying at 155 ° C. for 30 minutes in the ventilation dryer was measured (b) and calculated from the following formula. A weighing bottle was used for the measurement. Other operations were in accordance with JIS K 0067-1992 (chemical product weight loss and residue test method).
Solid content (%) = (b / a) × 100

<Molecular weight measurement>
The molecular weight was measured by GPC under the following conditions.
GPC: Tosoh (HLC-8120)
Column: Tosoh (TSKgel-SuperMP-M x 4)
Sample concentration: 0.1%
Flow rate: 0.6 ml / min Eluent: Tetrahydrofuran Column temperature: 40 ° C
Detector: Differential refractometer (RI)
Reference material: Polystyrene

<Glass transition point (Tg)>
Tg of the vinyl polymer (A), the acrylic adhesive polymer (B) and the adhesive composition was measured by DSC under the following conditions.
DSC: manufactured by TA Instrument (Q-100)
Temperature rise: 10 ° C / min Measurement atmosphere: Nitrogen

<Polymer composition>
The polymer composition was calculated from the monomer charge and the monomer consumption by GC measurement.
GC: Made by Agilent Technologies (7820A GC System)
Detector: FID
Column: 100% dimethylsiloxane (CP-Sil 5CB) Length 30m, inner diameter 0.32mm
Calculation method: Internal standard method

1. Synthetic Synthesis Example 1 of Vinyl Polymer (Synthesis of Polymer A-1)
In a four-necked flask with an internal volume of 1 liter, 45 parts by mass of methyl methacrylate (MMA), 5 parts by mass of styrene (St), 245 parts by mass of butyl acetate, dimethyl 2,2′-azobis (2-methylpropionate) ( A mixed solution consisting of 2.7 parts by mass of V-601 manufactured by Wako Pure Chemical Industries, Ltd. was charged, and the mixed solution was sufficiently deaerated by bubbling with nitrogen gas, and the internal temperature of the mixed solution was raised to 90 ° C. Separately, polymerization was performed by dropping a mixed liquid consisting of 180 parts by mass of MMA, 19 parts by mass of St, 24 parts by mass of V-601, and 90 parts by mass of butyl acetate into the flask from a dropping funnel over 5 hours. After completion of the dropping, the polymerization solution was dropped into 6000 parts by mass of hexane to isolate the vinyl polymer in the polymerization solution, thereby obtaining a polymer A-1. The polymer composition of the obtained polymer A-1 was calculated from the charged amount and the monomer consumption by GC measurement. As a result, it was composed of 90% by mass of MMA and 10% by mass of St, and was Mw5650, Mn3270, and Mw / Mn1.73. Tg was 80 ° C.
The composition and analysis results of the polymer A-1 are shown in Table 1.

Synthesis Example 2 (Synthesis of Polymer A-2)
A mixed solution consisting of 200 parts by mass of butyl acetate and 4.1 parts by mass of V-601 was charged into a 4-liter flask having an internal volume of 1 liter, and this mixture was sufficiently degassed by bubbling nitrogen gas. The internal temperature was raised to 90 ° C. Separately, polymerization is carried out by dropping a mixed liquid consisting of 114 parts by mass of MMA, 140 parts by mass of isobornyl methacrylate (IBXMA), 78 parts by mass of V-601 and 90 parts by mass of butyl acetate into the flask from a dropping funnel over 5 hours. It was. After completion of the dropwise addition, the polymer solution was dropped into a mixed solution consisting of 2800 parts by weight of methanol and 700 parts by weight of distilled water, whereby the vinyl polymer in the polymerization solution was isolated to obtain polymer A-2.
The composition and analysis results of the polymer A-2 are shown in Table 1.

Synthesis Example 3 (Synthesis of Polymer A-3)
A liquid mixture consisting of 75 parts by mass of butyl acetate and 1.7 parts by mass of V-601 is charged into a four-necked flask having an internal volume of 0.5 liter, and this mixture is sufficiently degassed by bubbling with nitrogen gas and mixed. The internal temperature of the liquid was raised to 90 ° C. Separately, polymerization was performed by dropping a mixed liquid consisting of 80 parts by mass of MMA, 63 parts by mass of IBXMA, 33 parts by mass of V-601, and 90 parts by mass of butyl acetate into the flask from a dropping funnel over 5 hours. After completion of the dropping, the polymerization solution was dropped into a mixed solution consisting of 2800 parts by mass of methanol and 700 parts by mass of distilled water, whereby the vinyl polymer in the polymerization solution was isolated to obtain a polymer A-3.
The composition and analysis results of the polymer A-3 are shown in Table 1.

Synthesis Example 4 (Synthesis of Polymer A-4)
A mixed solution consisting of 200 parts by mass of butyl acetate and 4.0 parts by mass of V-601 was charged into a 4-liter flask having an internal volume of 1 liter, and this mixture was sufficiently degassed by bubbling nitrogen gas. The internal temperature was raised to 90 ° C. Separately, polymerization was performed by dropping a mixed liquid composed of 59 parts by mass of MMA, 200 parts by mass of IBXMA, 75 parts by mass of V-601, and 90 parts by mass of butyl acetate into the flask from a dropping funnel over 5 hours. After completion of the dropping, the polymerization solution was dropped into a mixed solution consisting of 2800 parts by mass of methanol and 700 parts by mass of distilled water to isolate vinyl polymerization in the polymerization solution, thereby obtaining a polymer A-4.
The composition and analysis results of the polymer A-4 are shown in Table 1.

Synthesis Example 5 (Synthesis of Polymer A-5)
A four-necked flask with an internal volume of 1 liter is charged with a mixed solution consisting of 230 parts by mass of butyl acetate, 50 parts by mass of MMA, and 11.6 parts by mass of V-601, and this mixture is sufficiently degassed by bubbling with nitrogen gas. The internal temperature of the mixture was raised to 90 ° C. Separately, polymerization was carried out by dropping a mixed liquid consisting of 200 parts by mass of MMA, 46 parts by mass of V-601 and 90 parts by mass of butyl acetate into the flask from a dropping funnel over 5 hours. After completion of the dropping, the polymerization solution was added dropwise to 6000 parts by mass of hexane to isolate the vinyl polymer in the polymerization solution, thereby obtaining a polymer A-5.
The composition and analysis results of the polymer A-5 are shown in Table 1.

2. Synthesis Synthesis Example 6 of Acrylic Adhesive Polymer (Synthesis of Polymer B-1)
A 4-liter flask having an internal volume of 2 liters was charged with 285 parts by mass of methoxyethyl acrylate (MEA), 15 parts by mass of 2-hydroxyethyl acrylate (HEA), and 520 parts by mass of ethyl acetate. The mixture was sufficiently deaerated by bubbling, the internal temperature of the mixed solution was raised to 40 ° C., 11.5 parts by mass of azobisvaleronitrile (V-65) was charged, and polymerization was started. After 4 hours, the acrylic adhesive polymer was isolated by adding the polymerization solution dropwise to 10000 parts by mass of hexane to obtain a polymer B-1. The obtained polymer B-1 was composed of 95% by mass of MEA and 5% by mass of HEA and had Mw 500000, Mn 70000, and Mw / Mn 7.1.
Table 2 shows the composition and analysis results of the polymer B-1.

Synthesis Example 7 (Synthesis of polymer B-2)
MEA 255 parts by mass, 8 parts by mass of butyl acrylate (BA), 15 parts by mass of HEA, and 520 parts by mass of ethyl acetate are charged into a 2-liter flask having an internal volume of 2 liters, and this mixture is sufficiently degassed by bubbling nitrogen gas. Then, the internal temperature of the mixed solution was raised to 40 ° C., 11.4 parts by mass of V-65 was charged, and polymerization was started. After 4 hours, the acrylic adhesive polymer was isolated by adding the polymerization solution dropwise to 10000 parts by mass of hexane to obtain a polymer B-2. Obtained polymer B-2 consisted of 85 mass% of MEA, 10 mass% of BA, and 5 mass% of HEA, and was Mw 520000, Mn 80000, Mw / Mn 6.5.
Table 2 shows the composition and analysis results of the polymer B-2.

Synthesis Example 8 (Synthesis of Polymer B-3)
A 4-liter flask with an internal volume of 2 liters was charged with 188 parts by mass of MEA, 192 parts by mass of BA, 20 parts by mass of HEA, and 740 parts by mass of ethyl acetate, and this mixture was sufficiently degassed by bubbling nitrogen gas. The temperature was raised to 40 ° C., 10.3 parts by mass of V-65 was charged, and polymerization was started. After 4 hours, the acrylic adhesive polymer was isolated by dropping the polymerization solution into 10000 parts by mass of hexane to obtain a polymer B-3. The obtained polymer B-3 was composed of 47% by mass of MEA, 48% by mass of BA, and 5% by mass of HEA, and had Mw 510000, Mn 90000, and Mw / Mn 5.7.
Table 2 shows the composition and analysis results of the polymer B-3.

3. Production and evaluation of pressure-sensitive adhesive composition Example 1
Polymer A-1 obtained in Synthesis Example 1 was dissolved in ethyl acetate to prepare a polymer A-1 solution having a solid concentration of 30% by mass. Similarly, the polymer (B-1) obtained in Synthesis Example 6 was dissolved in ethyl acetate to prepare a polymer (B-1) solution having a solid content concentration of 30% by mass. 4 parts by mass of the polymer A-1 solution, 100 parts by mass of the polymer B-1 solution, and 0.16 parts by mass of Takenate D-110N (solid content concentration 75% by mass, manufactured by Mitsui Chemicals) as a crosslinking agent are mixed. A pressure-sensitive adhesive composition was obtained.

  This pressure-sensitive adhesive composition was applied onto a polyethylene terephthalate (PET) separator having a thickness of 38 μm so that the thickness after drying was 50 μm. By drying the pressure-sensitive adhesive composition at 80 ° C. for 4 minutes, ethyl acetate was removed and a crosslinking reaction was performed, and a PET separator having a thickness of 38 μm different from that of the separator was bonded, and 5 ° C. at 5 ° C. The adhesive film sample with a double-sided separator was obtained by standing for aging and aging (aging).

  The obtained adhesive film sample was subjected to various measurements and evaluations by the following methods. The obtained results are shown in Table 3.

<Gel fraction with respect to acrylic adhesive polymer (B)>
0.2 g of adhesive was collected from the adhesive film sample, and the initial weight of the adhesive was weighed. The adhesive was immersed in 50 g of ethyl acetate and allowed to stand at room temperature for 16 hours. Thereafter, the mixture was filtered through a 200 mesh wire mesh, and the residue remaining on the mesh was dried at 80 ° C. for 3 hours and weighed. From the initial weight and the residual weight, the gel fraction with respect to the acrylic adhesive polymer (B) was calculated by the following formula.
Gel fraction (%) = (weight of residue) / [(initial weight) × (solid content of acrylic adhesive polymer (B)) / (solid content of the entire pressure-sensitive adhesive composition)] × 100

<Transparency (haze value)>
The release film was peeled off from the adhesive film sample, transferred to a glass plate (1 mm thickness), and the other release film was peeled off. After standing at 23 ° C. and 50% RH for 1 day, measuring the haze value by using a haze meter “Haze Meter NDH2000” (model name) manufactured by Nippon Denshoku Co., Ltd. enables transparency in the composition. Evaluated.

<Peel strength for polypropylene (PP)>
The pressure-sensitive adhesive film sample was transferred to a PET film (100 μm) subjected to easy adhesion treatment to obtain a pressure-sensitive adhesive sheet for evaluation. The adherend was a PP plate (manufactured by Sumitomo Noblen, Nobrene MHB, 2 mm thickness), and the above adhesive sheet for evaluation was bonded to the plate, and a table pressure defoaming device TBR-200 (manufactured by Chiyoda Electric Co., Ltd.) was used. After pressure bonding at 5 MPa and 50 ° C. for 20 minutes, JIS Z-0237 “adhesive tape” was used under conditions of 23 ° C. and 85 ° C. using a tensile tester with a thermostatic bath, “Strograph R type” (manufactured by Toyo Seiki Co., Ltd.). According to the “Pressure sheet test method”, the 180-degree peel strength of the pressure-sensitive adhesive sheet was measured and used as the adhesive strength. The peeling speed was 300 mm / min.

<Tg of the surface layer portion of the pressure-sensitive adhesive layer>
From the peak area ratio of O1s and C1s measured by X-ray photoelectron spectroscopy (XPS) of the adhesive film sample, vinyl relative to the total amount of vinyl polymer (A) and acrylic adhesive polymer (B) in the surface layer portion of the adhesive layer Each mass fraction (w _A and w _B ) of the polymer (A) and the acrylic adhesive polymer ( _B ) was calculated, and the Tg of the surface layer portion was calculated based on the FOX formula.
XPS measurement was performed under the following conditions.
Apparatus: PHI5000 VersaProbe manufactured by ULVAC-PHI
X-ray: Al-Kα (1486.6 eV)
X-ray incident angle on sample: 0 ° (angle with respect to normal of sample measurement surface)
Photoelectron detection angle: 45 ° (angle with respect to normal of sample measurement surface)

ここで、
（Ｏ／Ｃ）_Ａ+B：粘着剤組成物を乾燥して得られた粘着剤層のＸＰＳ測定から求められるＯ１ｓとＣ１ｓのピーク面積比
Ｗ_Ａ：ビニル重合体（Ａ）及びアクリル系粘着性ポリマー（Ｂ）の総量に対するビニル重合体（Ａ）の質量分率
Ｍ_ｗ−Ａ：ビニル重合体（Ａ）の全構成単量体単位の加重平均分子量
Ｍ_ｗ−Ｂ：アクリル系粘着剤組成物（Ｂ）の全構成単量体単位の加重平均分子量
Ｎ_Ｏ−Ａ：ビニル重合体（Ａ）を構成する全構成単量体の平均単量体構造式中に含まれる酸素原子数
Ｎ_Ｏ−Ｂ：アクリル系粘着性ポリマー（Ｂ）を構成する全構成単量体の平均単量体構造式中に含まれる酸素原子数
Ｎ_Ｃ−Ａ：ビニル重合体（Ａ）を構成する全構成単量体の平均単量体構造式中に含まれる炭素原子数
Ｎ_Ｃ−Ｂ：アクリル系粘着性ポリマー（Ｂ）を構成する全構成単量体の平均単量体構造式中に含まれる炭素原子数 A specific method for calculating the mass fraction is described below.
The peak area ratio of O1s and C1s by XPS measurement is the pressure-sensitive adhesive layer surface layer part formed from a pressure-sensitive adhesive composition comprising a vinyl polymer (A) and an acrylic pressure-sensitive adhesive polymer (B) as shown in the following formula (1). It is represented by the ratio of the number of oxygen atoms and the number of carbon atoms present per unit weight.

here,
(O / C) _{A + B} : Peak area ratio between O1s and C1s determined from XPS measurement of the pressure-sensitive adhesive layer obtained by drying the pressure-sensitive adhesive composition W _A : vinyl polymer (A) and acrylic pressure-sensitive adhesive Mass fraction _Mw-A of vinyl polymer (A) with respect to the total amount of polymer (B): Weighted average molecular weight _Mw-B of all constituent monomer units of vinyl polymer (A): Acrylic adhesive composition Weighted average molecular weight N _O-A of all constituent monomer units in (B): Number of oxygen atoms N _O— contained in the average monomer structural formula of all constituent monomers constituting the vinyl polymer (A) _B : Number of oxygen atoms contained in the average monomer structural formula of all constituent monomers constituting the acrylic adhesive polymer (B) N _C-A : All constituent single quantities constituting the vinyl polymer (A) the number of carbon atoms contained averaged in the monomer structure of the body N _C-B: acrylic adhesive polymer The average number of carbon atoms contained in the monomer structure of the total constituent monomer constituting the (B)

ここで、
（Ｏ／Ｃ）_Ａ：ビニル重合体（Ａ）を乾燥して得られたフィルムのＸＰＳ測定から求められるＯ１ｓとＣ１ｓのピーク面積比

ここで、
（Ｏ／Ｃ）_Ｂ：アクリル系粘着性ポリマー（Ｂ）を乾燥して得られたフィルムのＸＰＳ測定から求められるＯ１ｓとＣ１ｓのピーク面積比 Moreover, the peak area ratio of O1s and C1s calculated | required by the XPS measurement of the film obtained by drying each single body of a vinyl polymer (A) and an acrylic adhesive polymer (B) is following Formula (2) and ( 3).

here,
(O / C) _A : Peak area ratio of O1s and C1s determined from XPS measurement of a film obtained by drying the vinyl polymer (A)

here,
(O / C) _B : Peak area ratio of O1s and C1s determined from XPS measurement of a film obtained by drying the acrylic adhesive polymer (B)

さらに、上記で求めたＷ_Ａの値と下記式（５）から、アクリル系粘着性ポリマー（Ｂ）の質量分率（Ｗ_Ｂ）が算出される。

ここで、
Ｗ_Ｂ：ビニル重合体（Ａ）及びアクリル系粘着性ポリマー（Ｂ）の総量に対するアクリル系粘着性ポリマー（Ｂ）の質量分率 The following formula (4) is derived from the above formulas (1) to (3), and from this, the mass fraction of the vinyl polymer (A) with respect to the total amount of the vinyl polymer (A) and the acrylic adhesive polymer (B). (W _A ) is calculated.

Further, the mass fraction (W _B ) of the acrylic pressure-sensitive adhesive polymer ( _B ) is calculated from the value of W _A obtained above and the following formula (5).

here,
W _B : Mass fraction of the acrylic adhesive polymer (B) with respect to the total amount of the vinyl polymer (A) and the acrylic adhesive polymer (B)

About Example 1, each element in the said Formula (4) is shown below.
(O / C) _{A + B} : 0.3 (actual value)
(O / C) _A : 0.3 (actual value)
(O / C) _B : 0.5 (actual value)
N _C-A : From the number of carbon atoms in the MMA1 molecule (5), the number of carbon atoms in the St1 molecule (8), and the composition ratio, 5 × 90 (%) + 8 × 10 (%) = 5.3
N _C-B : From the number of carbon atoms in MEA1 molecule (6), the number of carbon atoms in HEA1 molecule (5) and the composition ratio, 6 × 94 (%) + 5 × 6 (%) = 5.9
M _w−A : From the molecular weight of MMA (100), the molecular weight of St (104), and the composition ratio, 100 × 90 (%) + 104 × 10 (%) = 100
M _w−B : From the molecular weight of MEA (130), the molecular weight of HEA (116), and the composition ratio, 130 × 94 (%) + 116 × 6 (%) = 129
By substituting these values into the equation (4), W _A = 0.8 was obtained, and from the equation (5), W _B = 0.2 was obtained.

Next, Tg of the surface layer portion was calculated from the surface composition obtained by the measurement according to the formula of FOX represented by the following formula (6), and a value of 50.3 ° C. was obtained.
1 / [Tg of surface layer portion] (K) = W _A / Tg _A + W _B / Tg _B (6)
here,
Tg _A : Tg of vinyl polymer (A) (80 ° C.)
Tg _B : Tg of acrylic adhesive polymer (B) (−31 ° C.)

<Durability of curved laminated film>
A pressure-sensitive adhesive film was attached to one side of the pressure-sensitive adhesive film sample to prepare a pressure-sensitive adhesive sheet, and then cut to a width of 20 mm and a length of 12.5 mm. This was wound around a cylindrical bar of PP of 8 mmΦ, and was fixed to the cylindrical bar by laminating with a cellophane tape. By the above procedure, the pressure-sensitive adhesive sheet is affixed over approximately 50% of the circumference of each cylindrical bar. Next, with the cellophane tape fixed, a pressure bonding process was performed in an autoclave at 50 ° C., 0.5 MPa, for 20 minutes. After crimping, the sample was stored at 23 ° C. and 50% RH for 1 hour, and the cellophane tape was peeled off. The sample was allowed to stand at 23 ° C. for 24 hours and 120 ° C. for 24 hours, and the presence or absence of peeling of the pressure-sensitive adhesive sheet was measured. did.
◯: No peeling △: Distance from which the adhesive sheet peeled is 1 mm or less ×: Distance from which the adhesive sheet was peeled exceeded 1 mm

<Foaming resistance>
A laminated body in which an easy-adhesive PET film having a thickness of 100 μm was pasted on one side of an adhesive film sample and a PP plate or a polycarbonate (PC) plate was pasted on the other side was prepared. A pressure bonding treatment of 5 MPa for 20 minutes was performed. Thereafter, a load was applied to the laminate in a 60 ° C./90% constant temperature and humidity chamber for 24 hours, and the appearance after the load (whether foaming was present) was visually confirmed and evaluated according to the following criteria.
○: No change in appearance △: Area of the foamed portion is 10% or less with respect to the area of the test piece ×: Area of the foamed portion exceeds 10% with respect to the area of the test piece

Examples 2-6 and Comparative Examples 1-4
In Example 1, the types and ratios of the vinyl polymer and the acrylic pressure-sensitive adhesive polymer were changed as shown in Tables 3 and 4 to obtain a pressure-sensitive adhesive composition, and the same measurements as in Example 1 were performed. The results are shown in Tables 3 and 4.

  As shown in Table 3, in each of Examples 1 to 6 using the pressure-sensitive adhesive composition disclosed in this specification, the Tg of the surface layer portion of the pressure-sensitive adhesive layer is 40 ° C. rather than the Tg of the whole pressure-sensitive adhesive layer. As described above, the film exhibited high peel strength (23 ° C. and 85 ° C.) and good foam resistance against PP and PC plates. Especially, when the Tg of the surface layer portion of the pressure-sensitive adhesive layer is 60 ° C. or higher than the Tg of the whole pressure-sensitive adhesive layer and the Tg of the surface layer portion of the pressure-sensitive adhesive layer is 25 ° C. or higher, good curved surface adhesion is achieved even under high temperature conditions (120 ° C., 24 h).

  Furthermore, compared with Examples 4-6, in Examples 1-3, the 85-mass structural unit derived from the (meth) acrylic-acid alkoxyalkylester with respect to all the structural monomers of an acrylic adhesive polymer (B). %, The results showed good results in all of peel strength, curved surface adhesion and foam resistance.

  On the other hand, as shown in Table 4, in Comparative Examples 1 to 3 using the pressure-sensitive adhesive composition that does not segregate, no Tg distribution in the pressure-sensitive adhesive layer was observed, and both peel strengths at 23 ° C. and 85 ° C. were observed. While becoming low, curved-surface adhesiveness and foam resistance were not sufficient. In Comparative Example 4, the Tg of the surface layer portion of the pressure-sensitive adhesive layer and the Tg of the entire pressure-sensitive adhesive layer are similarly low, and the Tg of the surface layer portion of the pressure-sensitive adhesive layer is only 0.8 ° C. higher than the Tg of the entire pressure-sensitive adhesive layer. Therefore, neither curved-surface adhesiveness nor foaming resistance could be exhibited.

Claims (5)

A decorative film comprising an adhesive layer containing an adhesive composition containing a vinyl polymer (A) and an acrylic adhesive polymer (B) on at least one side of a substrate,
The vinyl polymer (A) has a glass transition temperature (Tg) of 30 ° C. or more and 200 ° C. or less, a number average molecular weight of 500 to 10,000, and 100 parts by mass of the acrylic adhesive polymer (B). 0.5 parts by mass or more and 60 parts by mass or less based on
When the pressure-sensitive adhesive composition is applied to a separator and dried to obtain a pressure-sensitive adhesive layer, the first Tg, which is the glass transition temperature of the pressure-sensitive adhesive layer as a whole, is −80 ° C. or higher and 10 ° C. or lower,
The second Tg, which is the glass transition temperature calculated from the surface layer portion obtained by X-ray photoelectron spectroscopy of the pressure-sensitive adhesive layer, is 30 ° C. or more higher than the first Tg.
Decorative film.   The decorative film according to claim 1, wherein the acrylic pressure-sensitive polymer (B) contains 85% by mass or more of a structural unit derived from (meth) acrylic acid alkoxyalkyl ester with respect to all the structural monomers. .   The decorative film of Claim 1 or 2 whose haze value of the said adhesive layer is 2.0 or less.   The peeling strength with respect to the polypropylene board in 85 degreeC of the adhesive sheet which equipped the 100-micrometer-thick polyethylene terephthalate film base material with the 50-micrometer-thick adhesive layer which consists of the said adhesive composition is 3.0 N / 25mm or more. 3. The decorative film according to any one of 3. The decorative molded body formed by sticking the decorative film in any one of Claims 1-4 to a molded body.