CN104830243B - Double-sided adhesive sheet and its manufacturing method - Google Patents

Abstract

The present invention relates to double-sided adhesive sheet and its manufacturing methods.The present invention provides height difference absorbability excellent double-sided adhesive sheet and its manufacturing method.Double-sided adhesive sheet of the invention is for the fixed component for constituting portable electronic device, the double-sided adhesive sheet has acrylic adhesive layer, the acrylic adhesive layer contains acrylic polymer as basic polymer, the acrylic polymer contain 9~30 mass % derive from polar monomer Component units, the acrylic adhesive layer with a thickness of 280 μm or more.

Description

Double-sided adhesive sheet and its manufacturing method

Technical field

The present invention relates to double-sided adhesive sheet and its manufacturing methods.

Background technique

In the past, double-sided adhesive sheet is used in various technical fields.For example, portable in mobile phone, portable data assistance etc. In the field of formula electronic equipment, double-sided adhesive sheet is used for the fixation between various components.In patent document 1, it as its an example, drapes over one's shoulders Revealed using double-sided adhesive sheet will protect portable electronic device display unit protection panels (lens) be fixed to shell on Technology.The double-sided adhesive sheet be glued in the state of being clipped between protection panels and shell on these components and by these It is fixed to each other between component.

Patent document

Patent document 1: Japanese Unexamined Patent Publication 2009-108314 bulletin

Summary of the invention

Problem to be solved by the invention

In recent years, it as the component (such as shell, framework) for constituting portable electronic device, is used sometimes comprising plastics Injection-molded article.Component (hereinafter referred to as injection moulding component) comprising injection-molded article due to general metal member phase Popular portable electronic device is used for than being able to suppress the reasons such as cost.

But in this injection moulding component, sometimes due to warpage, shrinkage cavity etc. and to form the height difference portion distorted (such as convex Portion).When pasting existing double-sided adhesive sheet on such injection moulding component, worry in double-sided adhesive sheet and injection moulding structure Gap is formed between the height difference portion of part, which becomes the various bad reasons such as leak, the light leakage of portable electronic device.

Problem of the present invention is that solving the problems, such as existing above-mentioned various, and purpose below is solved.That is, of the invention It is designed to provide the excellent double-sided adhesive sheet of height difference absorbability and its manufacturing method.

The means used to solve the problem

The present inventor in order to realize that foregoing purpose has carried out research extensively and profoundly, as a result, it has been found that, constituted for fixed In the double-sided adhesive sheet of the component of portable electronic device, there is acrylic adhesive layer, the acrylic adhesive layer Contain acrylic polymer as basic polymer, the acrylic polymer contains 9~30 mass % from polarity The Component units of monomer, and the acrylic adhesive layer with a thickness of 280 μm or more of double-sided adhesive sheet, height difference is inhaled The property received is excellent, so as to complete the present invention.

In aforementioned double-sided adhesive sheet, the acrylic polymer can be derived from containing 50 mass % or more has carbon former The Component units of (methyl) alkyl acrylate for the linear or branched alkyl group that subnumber is 1~20.

In aforementioned double-sided adhesive sheet, the acrylic polymer can derive from list containing carboxyl containing 2 mass % or more The Component units of body are as the Component units for deriving from polar monomer.

In aforementioned double-sided adhesive sheet, the acrylic polymer can derive from hydroxyl list containing 2 mass % or more The Component units of body are as the Component units for deriving from polar monomer.

In aforementioned double-sided adhesive sheet, the acrylic polymer can derive from second containing heterocycle containing 10 mass % or more The Component units of alkenyl monomer are as the Component units for deriving from polar monomer.

In aforementioned double-sided adhesive sheet, the acrylic polymer can be containing from more than two polymerizable officials The Component units for the polyfunctional monomer that can be rolled into a ball.

In aforementioned double-sided adhesive sheet, transmissivity on the thickness direction of the acrylic adhesive layer can for 5% with Under.

In aforementioned double-sided adhesive sheet, described adhesive layer can contain colorant, and the content of the colorant can be 0.25 mass % or less.

In aforementioned double-sided adhesive sheet, the colorant can be black colorant.

In aforementioned double-sided adhesive sheet, the solvent insoluble component ratio of described adhesive layer can be 50% or more.

In aforementioned double-sided adhesive sheet, the solvent insoluble component ratio of described adhesive layer can be 60% or more.

In aforementioned double-sided adhesive sheet, the component for constituting portable electronic device may include the injection moulding of plastics Product.

In aforementioned double-sided adhesive sheet, shape when vertical view may include selected from by band-like, strip, U-shaped, L shape and frame-shaped Any one in the group of composition.

The manufacturing method of double-sided adhesive sheet of the invention includes: will be containing a variety of lists for being used to form acrylic polymer Body ingredient, the monomer component a part polymerization obtained from partial polymer, Photoepolymerizationinitiater initiater and colorant bonding Agent composition is applied on supporter and the process of film of the formation comprising described adhesive composition；With

To the film irradiation light, makes the monomer component photopolymerization in the film and form the acrylic polymer It closes object and makes the curing of coating and the process that obtains acrylic adhesive layer；

The use level of Photoepolymerizationinitiater initiater described in described adhesive composition is formed relative to the acrylic compounds 100 mass parts of whole monomer components of polymer are 0.3 mass parts or more, and colorant described in described adhesive composition Use level relative to whole 100 mass parts of monomer component be 0.25 below the mass.

Invention effect

According to the present invention it is possible to provide the excellent double-sided adhesive sheet of height difference absorbability and its manufacturing method.

Detailed description of the invention

Fig. 1 is the schematic sectional view of the double-sided adhesive sheet of embodiment 1.

Fig. 2 is the approximate vertical view for indicating the sample for evaluation group of the evaluation for height difference absorbability.

Fig. 3 is the line A-A cross-sectional view of Fig. 2.

Appended drawing reference

10 double-sided adhesive sheets

20 acrylic adhesive layers

30,40 release liner

Specific embodiment

The double-sided adhesive sheet of present embodiment includes to polymerize based on there is at least one layer to contain acrylic polymer The double-sided adhesive sheet of the acrylic adhesive layer (hereinafter sometimes referred to simply as " adhesive phase ") of object.In addition, in general, " double Face bonding sheet " is otherwise referred to as the different titles such as " double-faced adhesive tape ", " both-sided adhesive film ", in this specification, will state It is unified for " double-sided adhesive sheet ".In addition, the surface of the adhesive phase in double-sided adhesive sheet is known as " adhesive surface " sometimes.

As the form of double-sided adhesive sheet, preferably without substrate (supporter), so-called no substrate both-sided adhesive Piece.This is the composition for only including acrylic adhesive layer without substrate double-sided adhesive sheet.Hereinafter, being had for double-sided adhesive sheet Acrylic adhesive layer be described in detail.

(acrylic adhesive layer)

Adhesive phase contains acrylic polymer as basic polymer (main component).Adhesive phase (100 matter Measure %) in the containing ratio (quality %) of acrylic polymer be preferably 50 mass % or more, more preferably 60 mass % or more, Further preferably 75 mass % or more.In addition, in adhesive phase the containing ratio (quality %) of acrylic polymer the upper limit Be not particularly limited, preferably 100 mass % hereinafter, more preferably 99.9 mass % hereinafter, further preferably 99 mass % Below.

(acrylic polymer)

Acrylic polymer (100 mass %) derives from the Component units of polar monomer containing 9~30 mass %.

(polar monomer)

Polar monomer includes at least to have a kind of polar group and the monomer containing polymerizable unsaturated bond.Acrylic compounds Polymer (100 mass %) preferably comprises 12 mass % or more, further preferably 15 mass % or more from polar monomer Component units.In addition, acrylic polymer (100 mass %) preferably comprises 30 mass % or less, further preferably 26 matter Measure the Component units that % or less derives from polar monomer.

It as polar monomer, can enumerate for example: carboxyl group-containing monomer, hydroxyl monomer and containing heterocyclic vinyl monomer Deng.These monomers may be used singly or two or more in combination.

In addition, a preferred embodiment as the Component units from polar monomer, can enumerate for example: from containing The Component units of carboxylic monomer, from hydroxyl monomer Component units with derive from the composition list containing heterocyclic vinyl monomer Member is used in combination.

(carboxyl group-containing monomer)

Acrylic polymer (100 mass %) preferably comprises 2 mass % or more, further preferably 3 mass % or more Component units derived from carboxyl group-containing monomer are as the Component units for deriving from polar monomer.In addition, acrylic polymer (100 Quality %) preferably comprise Component units work of the 5 mass % or less, further preferably 4 mass % or less from carboxyl group-containing monomer For from the Component units of polar monomer.

As carboxyl group-containing monomer, can enumerate for example: (methyl) acrylic acid, itaconic acid, maleic acid, fumaric acid, crotonic acid, Iso-crotonic acid, their acid anhydrides (for example, maleic anhydride, itaconic anhydride etc. contain anhydride monomers) etc..These monomers can individually make With or be used in combination.

In addition, in this specification, " (methyl) acrylic acid " expression " acrylic acid " and/or " methacrylic acid " (" acrylic acid " Either or both in " methacrylic acid ").

(hydroxyl monomer)

Acrylic polymer (100 mass %) preferably comprises 2 mass % or more, further preferably 3 mass % or more Component units derived from hydroxyl monomer are as the Component units for deriving from polar monomer.In addition, acrylic polymer (100 Quality %) preferably comprise Component units work of the 5 mass % or less, further preferably 4 mass % or less from hydroxyl monomer For from the Component units of polar monomer.

It as hydroxyl (hydroxy) monomer, can enumerate for example: (methyl) acrylic acid 2- hydroxy methacrylate, (methyl) propylene Sour 3- hydroxy propyl ester, (methyl) acrylic acid 4- hydroxybutyl, the own ester of (methyl) acrylic acid 6- hydroxyl, vinyl alcohol, allyl alcohol etc..This A little monomers may be used singly or two or more in combination.

(containing heterocyclic vinyl monomer)

Acrylic polymer (100 mass %) preferably comprise 10 mass % or more, further preferably 12 mass % or more, Further preferably 15 mass % or more are used as from the Component units containing heterocyclic vinyl monomer and derive from polar monomer Component units.In addition, acrylic polymer (100 mass %) preferably comprises 30 mass % or less, further preferably 25 matter Amount % or less, further preferably 20 mass % or less is used as from the Component units containing heterocyclic vinyl monomer and derives from The Component units of polar monomer.

As heterocyclic vinyl monomer is contained, can enumerate for example: n-vinyl-2-pyrrolidone, (methyl) acryloyl Quinoline, N- vinylpiperidone, N- vinyl piperazine, N- vinyl pyrrole, N- vinyl imidazole, N- vinyl caprolactam etc..This A little monomers may be used singly or two or more in combination.

((methyl) alkyl acrylate)

In addition, acrylic polymer (100 mass %), which preferably comprises 50 mass % or more and derives from, has carbon atom number 1 The structure of (methyl) alkyl acrylate (sometimes referred to simply as " (methyl) alkyl acrylate ") of~20 linear or branched alkyl group At unit.

Acrylic polymer (100 mass %) further preferably 60 mass % or more, further preferably 70 matter Measure the Component units that % or more derives from (methyl) alkyl acrylate.In addition, acrylic polymer (100 mass %) is preferred The Component units of (methyl) alkyl acrylate are derived from containing 85 mass % or less, further preferably 80 mass % or less.

It as (methyl) alkyl acrylate, can enumerate for example: (methyl) methyl acrylate, (methyl) acrylic acid second Ester, (methyl) propyl acrylate, (methyl) isopropyl acrylate, (methyl) n-butyl acrylate, (methyl) isobutyl acrylate, (methyl) sec-butyl acrylate, (methyl) tert-butyl acrylate, (methyl) amyl acrylate, (methyl) isoamyl acrylate, (first Base) Hexyl 2-propenoate, (methyl) heptylacrylate, (methyl) 2-ethyl hexyl acrylate, (methyl) 2-EHA, (methyl) Isooctyl acrylate monomer, (methyl) nonyl acrylate, the different nonyl ester of (methyl) acrylic acid, (methyl) decyl acrylate, (methyl) propylene Sour isodecyl ester, (methyl) acrylic acid hendecane base ester, (methyl) dodecylacrylate, (methyl) acrylic acid tridecyl Ester, (methyl) acrylic acid tetradecane base ester, (methyl) acrylic acid pentadecane base ester, (methyl) aliphatic acrylate, (first Base) acrylic acid heptadecane base ester, (methyl) octadecyl acrylate, (methyl) acrylic acid nonadecane base ester, (methyl) propylene Sour eicosane base ester etc..These monomers may be used singly or two or more in combination.

In addition, preferably there is the linear or branched alkyl group of carbon atom number 1~14 as (methyl) alkyl acrylate (methyl) alkyl acrylate, more preferably (methyl) acrylic acid alkyl of the linear or branched alkyl group with carbon atom number 1~8 Ester, further preferred n-butyl acrylate (BA), 2-EHA (2EHA), Isooctyl acrylate monomer, the different nonyl of acrylic acid Ester etc..

(polyfunctional monomer)

In addition, acrylic polymer can be containing from more than two polymerizable officials containing unsaturated double-bond The Component units for the polyfunctional monomer (hereinafter sometimes referred to simply as " polyfunctional monomer ") that can be rolled into a ball.

Acrylic polymer (100 mass %) preferably comprises 0.01 mass % or more, further preferably 0.02 mass % Above, further preferably 0.05 mass % or more derives from the Component units of polyfunctional monomer.In addition, acrylic Object (100 mass %) preferably comprises 0.5 mass % or less, further preferably 0.3 mass % or less from polyfunctional monomer Component units.

It as polyfunctional monomer, can enumerate for example: hexylene glycol two (methyl) acrylate, butanediol two (methyl) propylene Acid esters, (poly-) ethylene glycol two (methyl) acrylate, (poly-) propylene glycol two (methyl) acrylate, neopentyl glycol two (methyl) third Olefin(e) acid ester, pentaerythrite two (methyl) acrylate, pentaerythrite three (methyl) acrylate, dipentaerythritol six (methyl) third Olefin(e) acid ester, trimethylolpropane tris (methyl) acrylate, tetramethylol methane three (methyl) acrylate, (methyl) acrylic acid Allyl ester, (methyl) vinyl acrylate, divinylbenzene, epoxy acrylate, polyester acrylate, carbamate propylene Acid esters etc..These monomers may be used singly or two or more in combination.

In addition, when containing in acrylic polymer from the Component units of polyfunctional monomer, acrylic polymer Acrylic polymer containing cross-linking type, coherency, bonding force of adhesive phase etc. improve.

(other monomers)

In the range of not damaging the purpose of the present invention, acrylic polymer can be containing other other than above-mentioned monomer Monomer is as Component units.It as such monomer, can enumerate for example: (methyl) acrylamide, N, N- dimethyl (methyl) Acrylamide, N- methylol (methyl) acrylamide, N- methoxy (methyl) acrylamide, N- butoxymethyl (methyl) The amide-containings monomers such as acrylamide, N- ethoxy (methyl) acrylamide；(methyl) acrylate, (methyl) propylene The emulsion stabilities such as sour dimethylamino ethyl ester, (methyl) tbutylaminoethylacrylate；(methyl) glycidyl Ester, (methyl) acrylic acid methylglycidyl esters etc. contain epoxy based monomers；The cyano-containings monomer such as acrylonitrile, methacrylonitrile；Second The monomers containing sulfonic group such as sodium olefin sulfonate；The phosphorous acid-based monomers such as acryloyl phosphoric acid 2- hydroxy methacrylate；N-cyclohexylmaleimide, The monomers containing imide such as isopropylmaleimide；The lists containing isocyanate group such as 2- methylacryoyloxyethyl isocyanates Body；The vinyl esters such as vinyl acetate, vinyl propionate；The aromatic ethenyl compounds such as styrene, vinyltoluene；Second The alkene such as alkene, butadiene, isoprene, isobutene or dienes；The vinyl ethers such as vinyl alkyl ethers；Vinyl chloride etc..This A little monomers may be used singly or two or more in combination.

(manufacturing method of acrylic polymer)

Known or usual polymerization preparation can be used in acrylic polymer.As polymerization, can enumerate Such as: solution polymerization process, emulsion polymerization, mass polymerization, light polymerization method etc..Wherein, when preparing acrylic polymer, Preferably by the heat cure reaction or active energy beam for using the polymerization initiators such as thermal polymerization, Photoepolymerizationinitiater initiater (such as ultraviolet light) curing reaction.Especially since have many advantages, such as the thickness for shortening polymerization time, increasing adhesive phase, because This is preferably by the curing reaction for using Photoepolymerizationinitiater initiater.

For example, can be (such as purple by irradiating active energy beam to the monomer composition for being combined with Photoepolymerizationinitiater initiater Outside line) and make monomer polymerization, thus prepare acrylic polymer.In addition, when preparing acrylic polymer, can with polymerize Initiator cooperates the other ingredients contained in adhesive phase together.In addition, the thermal polymerization for being used to prepare acrylic polymer is drawn The polymerization initiators such as hair agent, Photoepolymerizationinitiater initiater may be used singly or two or more in combination.

As thermal polymerization, can enumerate for example: azo type polymerization initiator [such as 2,2 '-azodiisobutyronitriles, 2,2 '-azos bis- (2- methylbutyronitriles), bis- (2 Methylpropionic acid) dimethyl esters of 2,2 '-azos, bis- (the 4- cyano penta of 4,4 '-azos Acid), azobisisovaleronitrile, bis- (2- amidine propane) dihydrochlorides of 2,2 '-azos, the bis- [2- (5- methyl -2- imidazoles of 2,2 '-azos Quinoline -2- base) propane] dihydrochloride, bis- (the 2- methyl-prop amidine) dithionates of 2,2 '-azos, bis- (N, the N methylenes of '-two of 2,2 '-azos Base isobutyl amidine) dihydrochloride etc.], peroxide type polymerization initiator is (for example, dibenzoyl peroxide, peroxidating maleic acid The tert-butyl ester, lauroyl peroxide etc.), oxidation-reduction type polymerization initiator etc..As the usage amount of thermal polymerization, without spy It does not limit, as long as the range that can be used as thermal polymerization in the past.

As Photoepolymerizationinitiater initiater, can enumerate for example: benzoin ethers Photoepolymerizationinitiater initiater, acetophenones photopolymerization are drawn Send out agent, α -one alcohols Photoepolymerizationinitiater initiater, aromatic sulfonyl class Photoepolymerizationinitiater initiater, photolytic activity oximes Photoepolymerizationinitiater initiater, Benzoin class Photoepolymerizationinitiater initiater, benzil class Photoepolymerizationinitiater initiater, benzophenone Photoepolymerizationinitiater initiater, ketal class photopolymerization Initiator, thioxanthene ketone class Photoepolymerizationinitiater initiater, acylphosphine oxide class Photoepolymerizationinitiater initiater etc..

As the benzoin ethers Photoepolymerizationinitiater initiater, can enumerate for example: benzoin methylether, benzoin ethyl ether, benzene Acyloin propyl ether, benzoin iso-propylether, benzoin isobutyl ether, 2,2- dimethoxy -1,2- diphenylethane -1- ketone (BASF AG Manufacture, trade name: IRGACURE 651), anisoin methyl ether etc..As the acetophenones Photoepolymerizationinitiater initiater, Ke Yilie It illustrates such as: 1- hydroxycyclohexyl phenyl ketone (BASF AG's manufacture, trade name: IRGACURE 184), 4- phenoxy group dichloro-benzenes Ethyl ketone, 4- tert-butyl dichloroacetophenone, 1- [4- (2- hydroxyl-oxethyl) phenyl] -2- hydroxy-2-methyl -1- propane -1- ketone [BASF AG's manufacture, trade name: IRGACURE2959], 2- hydroxy-2-methyl -1- phenyl-propane -1- ketone [BASF AG's system Make, trade name: DAROCUR 1173], methoxyacetophenone etc..As the α -one alcohols Photoepolymerizationinitiater initiater, can enumerate Such as: 2- methyl -2- hydroxypropiophenonepreparation, 1- [4- (2- hydroxyethyl) phenyl] -2- hydroxy-2-methyl propane -1- ketone etc..

As the aromatic sulfonyl class Photoepolymerizationinitiater initiater, can enumerate for example: 2- naphthalene sulfonyl chloride etc..As described Photolytic activity oximes Photoepolymerizationinitiater initiater can be enumerated for example: 1- phenyl -1,2- propanedione -2- (O- carbethoxyl group) oxime etc..It is described In benzoin class Photoepolymerizationinitiater initiater, including, for example, benzoin etc..In the benzil class Photoepolymerizationinitiater initiater, including, for example, benzene Even acyl etc..In the benzophenone Photoepolymerizationinitiater initiater, including, for example: benzophenone, benzoylbenzoic acid, 3,3 '-diformazans Base -4- methoxy benzophenone, polyvinyl benzophenone, Alpha-hydroxy cyclohexyl phenyl ketone etc..The ketal class photopolymerization In initiator, including, for example, benzil dimethyl ketal etc..In the thioxanthene ketone class Photoepolymerizationinitiater initiater, including, for example, thioxanthene Ketone, 2-chlorothioxanthone, 2- methyl thioxanthones, 2,4- dimethyl thioxanthone, isopropyl thioxanthone, bis- clopenthixal ketone of 2,4-, 2,4- Diethyl thioxanthone, isopropyl thioxanthone, 2,4- diisopropylthioxanthone, dodecyl thioxanthones etc..

It as acylphosphine oxide class Photoepolymerizationinitiater initiater, can enumerate for example: bis- (2,6- Dimethoxybenzoyl) benzene Base phosphine oxide, bis- (2,6- Dimethoxybenzoyls) (2,4,4- tri-methyl-amyl) phosphine oxide, bis- (2,6- dimethoxy benzene first Acyl group) normal-butyl phosphine oxide, bis- (2,6- Dimethoxybenzoyls) (2- methylpropane -1- base) phosphine oxide, bis- (2,6- diformazans Oxygroup benzoyl) it is (1- methylpropane -1- base) phosphine oxide, bis- (2,6- Dimethoxybenzoyl) tert-butyl phosphine oxides, double (2,6- Dimethoxybenzoyl) cyclohexyl phosphine oxide, bis- (2,6- Dimethoxybenzoyl) octyl phosphine oxides, bis- (2- first Oxygroup benzoyl) (2- methylpropane -1- base) phosphine oxide, bis- (2- methoxybenzoyl bases) (1- methylpropane -1- base) oxygen Change phosphine, bis- (2,6- diethoxy benzoyls) (2- methylpropane -1- base) phosphine oxide, bis- (2,6- diethoxy benzoyls) (1- methylpropane -1- base) phosphine oxide, bis- (2,6- dibutoxy benzoyls) (2- methylpropane -1- base) phosphine oxide, it is bis- (2, 4- Dimethoxybenzoyl) (2- methylpropane -1- base) phosphine oxide, bis- (2,4,6- trimethylbenzoyl) (2,4- diamyls Phenyl) phosphine oxide, bis- (2,6- Dimethoxybenzoyl) benzyl phosphine oxides, bis- (2,6- Dimethoxybenzoyls)- 2- phenyl propyl phosphine oxide, bis- (2,6- Dimethoxybenzoyl) -2- phenylethyl phosphine oxides, bis- (2,6- dimethoxy benzenes Formoxyl) benzyl phosphine oxide, bis- (2,6- Dimethoxybenzoyl) -2- phenyl propyl phosphine oxides, bis- (2,6- dimethoxy benzenes Formoxyl) -2- phenylethyl phosphine oxide, 2,6- Dimethoxybenzoyl benzyl butyl phosphine oxide, 2,6- dimethoxy benzene first Acyl group octyl phosphine oxide, bis- (2,4,6- trimethylbenzoyl) -2,5- diisopropyl phenyl phosphine oxides, bis- (2,4,6- Trimethylbenzoyl) it is -2- aminomethyl phenyl phosphine oxide, bis- (2,4,6- trimethylbenzoyl) -4- aminomethyl phenyl phosphine oxides, double (2,4,6- trimethylbenzoyl) -2,5- diethyl phenyl phosphine oxide, bis- (2,4,6- trimethylbenzoyl) -2,3,5,6- Tetramethylphenyl phosphine oxide, bis- two n-butoxyphenyl phosphine oxides of (2,4,6- trimethylbenzoyl) -2,4-, 2,4,6- front three Base benzoyl diphenyl phosphine oxide, bis- (2,6- Dimethoxybenzoyl) -2,4,4- trimethylpentylphosphine oxides, it is bis- (2, 4,6- trimethylbenzoyl) isobutyl group phosphine oxide, 2,6- Dimethoxybenzoyl -2,4,6- trimethylbenzoyl-just Butyl phosphine oxide, bis- (2,4,6- trimethylbenzoyl) phenyl phosphine oxides, bis- (2,4,6- trimethylbenzoyl) -2,4- two Butoxy phenyl phosphine oxide, 1,10- bis- [bis- (2,4,6- trimethylbenzoyl) phosphine oxides] decane, three (2- toluyls Base) phosphine oxide etc..

As long as the usage amount of Photoepolymerizationinitiater initiater can form acrylic polymer by photopolymerization reaction, without spy It does not limit, for example, 100 mass parts of whole monomer components for being formed relative to acrylic polymer are preferably 0.01~5 Mass parts, more preferably 0.03~3 mass parts, further preferably 0.05~2 mass parts.The usage amount of Photoepolymerizationinitiater initiater is When such range, it can be sufficiently carried out polymerization reaction, and be able to suppress the decline of the molecular weight of the polymer of generation.Knot Fruit, it can be ensured that be formed by the cohesiveness etc. of adhesive phase.

When activating Photoepolymerizationinitiater initiater, irradiating active energy beam to the monomer composition for being combined with Photoepolymerizationinitiater initiater is Important.As such active energy beam, can enumerate for example: alpha ray, β ray, gamma-rays, neutron ray, electronics are penetrated The ionizing rays such as line, ultraviolet light etc., particularly preferred ultraviolet light.In addition, the irradiation energy of active energy beam, irradiation time, photograph Shooting method etc. is not particularly limited, as long as Photoepolymerizationinitiater initiater can be made to activate and the reaction of monomer component occurs.

The weight average molecular weight (Mw) of acrylic polymer is, for example, 100,000~5,000,000.Acrylic polymer Weight average molecular weight measurement can by GPC (gel permeation chromatography) method carry out polystyrene conversion find out.Specifically, TSKgelGMH-H (20) × 2 can be used as column, uses tetrahydrofuran in the HPLC8020 that TOSOH Co., Ltd manufactures Solvent is measured under conditions of flow velocity 0.5ml/ minutes.

(colorant)

Adhesive phase can contain colorant as the ingredient other than acrylic polymer.Adhesive phase, which passes through to contain, to be had Toner and have appearance design, optical characteristics (light-proofness, light reflective etc.).Colorant can be used alone or two kinds with On be applied in combination.

In addition, the containing ratio (%) of colorant is not particularly limited in adhesive phase (100 mass %), it can be according to purpose It suitably sets, such as preferably 0.25 mass % is hereinafter, more preferably 0.20 mass % or less.In addition, adhesive phase (100 matter Measure %) in colorant containing ratio (%) for example be preferably 0.1 mass % or more.

For example, the visible transmission in the case that adhesive phase is used for shading purposes, on the thickness direction of adhesive phase Rate is not particularly limited, and preferably 5.0% hereinafter, more preferably 3.0% or less.Transmission of visible light can pass through aftermentioned reality Apply the method measurement recorded in example.

In addition, adhesive phase is preferably coloured to black in the case that adhesive phase is used for shading purposes.As being used for The black colorant of adhesive phase can be enumerated for example: carbon black (for example, furnace black, channel black, acetylene black, thermal crack black, Lampblack), graphite, copper oxide, manganese dioxide, nigrosine, black, titanium is black, Cyanine Black, active carbon, ferrite are (for example, non magnetic Ferrite, magnetic ferrites), magnetic iron ore, chromium oxide, iron oxide, molybdenum disulfide, chromium complex, combined oxidation species black color Element, the organic black pigment of Anthraquinones etc..Wherein, from the viewpoint of cost, availability, preferred carbon black.

In addition, adhesive phase is preferably coloured to white in the case that adhesive phase is used for light reflection purposes.As with In the white color agents of adhesive phase, can enumerate for example: titanium oxide is (for example, rutile titanium dioxide, Detitanium-ore-type dioxy Change the titanium dioxide such as titanium), zinc oxide, aluminium oxide, silica, zirconium oxide, magnesia, calcium oxide, tin oxide, barium monoxide, oxidation Caesium, yttrium oxide, magnesium carbonate, calcium carbonate (for example, precipitated calcium carbonate, powdered whiting etc.), barium carbonate, zinc carbonate, aluminium hydroxide, Calcium hydroxide, magnesium hydroxide, zinc hydroxide, alumina silicate, magnesium silicate, calcium silicates, barium sulfate, calcium sulfate, barium stearate, the flowers of zinc, Zinc sulphide, talcum, silica, aluminium oxide, clay, kaolin, titanium phosphate, mica, gypsum, white carbon black, diatomite, swelling The Inorganic whites such as soil, lithopone, zeolite, sericite, endellite colorant, acrylic resin particle, polystyrene type tree Fat granule, polyurethane based resin particle, amide resin particle, polycarbonate resin particle, polysiloxanes resin particle, Organic white color agents such as ureaformaldehyde resin particle, melamine resin particle etc..

(other additives)

In the range of not damaging the purpose of the present invention, adhesive phase can also contain additive as shown below.As Additive can be enumerated for example: the metal powder of copper, nickel, aluminium, chromium, iron, stainless steel etc., calcium carbonate are (for example, powdered whiting, light Matter calcium carbonate), magnesium carbonate, sodium carbonate, the hydroxide such as carbonate, aluminium hydroxide, the magnesium hydroxide such as calcium carbonate, talcum, mica, Clay, bentonite, silica, aluminium oxide, alumina silicate, titanium oxide, hollow microsphere, heat-expandable microsphere, tackifier, crosslinking agent (such as epoxies crosslinking agent, isocyanates crosslinking agent, polysiloxane-based crosslinking agent,Oxazolines crosslinking agent, aziridines are handed over Join agent, silane-type cross-linking agent, alkyl etherified melamine class crosslinking agent, metal-chelating species crosslinking agent), crosslinking accelerator, silicon Alkane coupling agent, age resister, pigment, dyestuff, ultraviolet absorbing agent, antioxidant, chain-transferring agent, plasticizer, softening agent, prevent it is quiet Electric agent, solvent, polymer, adhesive (such as rubber adhesive, vinyl alkyl ethers adhesive, polysiloxane-based bonding Agent, polyester adhesive, polyamide-based adhesive, polyurethane binding, fluorine-containing type adhesive, epoxy adhesive) etc..This A little additives may be used singly or two or more in combination.

Adhesive phase preferably has the structure for containing substantially no bubble.In this specification, " containing substantially no bubble " Refer to other than the case where being inevitably mixed into, does not form bubble within the adhesive layer actively.In such adhesive phase The content of bubble is preferably zero.In addition, total volume of the containing ratio of bubble relative to adhesive phase in actual adhesive phase (100 volume %) is preferably 3 volume % hereinafter, more preferably 1 volume % or less.

In addition, the containing ratio (volume %) of bubble can be measured by the following method in adhesive phase.

(measuring method)

(1) adhesive phase through-thickness is cut off, production inhibits the measurement sample of the state of the damage to cut surface as far as possible Product.Furthermore it is possible to adhesive phase is immersed in liquid nitrogen, then by described adhesive fault rupture, to make measurement sample.

(2) then, using electric field emission type scanning electron microscope (FE-SEM), (Co., Ltd. Hitachi's high-tech is manufactured, type Number: 100 times of displays S-4800) are amplified into the section (section, the plane of disruption) of obtained measurement sample.

(3) then, amplification display the section in, will be surrounded by (wide 1mm) × (thickness of adhesive phase) four The part of side shape is set as reference area S1, finds out the total area S2 for the bubble portion for including in the S1.

(4) bubble rate (%) in the section is found out by (S2/S1) × 100.

(5) operation for repeating above-mentioned (1)~(4), adhesive phase is taken with amounting at equal intervals at 5 positions in one direction Sample, the containing ratio (volume %) using the average value of obtained each bubble rate as bubble in adhesive phase.

(manufacturing method of adhesive phase (double-sided adhesive sheet))

Adhesive phase is formed using such as adhesive composition.As adhesive composition, as long as being capable of forming above-mentioned Adhesive phase is then not particularly limited, and can suitably be selected according to purpose.As adhesive composition, examined from viewpoints such as operability Consider the adhesive composition, it is preferable to use curing type, the adhesive composition of the curing type contains: containing being used to form propylene The monomer composition of the various of monomer ingredient of acids polymers, the polymerization initiator for making the polymerizing monomer components and according to Need the mixture of other ingredients such as colorant to be added.In particular, as adhesive composition, it is preferable to use photopolymerization causes Adhesive composition of the agent as the light-cured type of polymerization initiator.The adhesive composition of curing type is so-called no-solvent type Adhesive composition, can be prepared by mixing described polymerization initiator etc. in the monomer composition.

In addition, the monomer composition is including, for example, (methyl) alkyl acrylate, (the hydroxyl list of monomer containing acidic-group Body, carboxyl group-containing monomer), the mixture of each monomer component containing heterocyclic vinyl monomer etc..The monomer composition according to monomer at Point type, ratio of components etc. and it is different, but be usually in a liquid state.Therefore, to improve the viscosity of the monomer composition, improve behaviour For the purpose of property made (operability) etc., monomer component contained in the monomer composition can be made partially polymerized and form part Polymer.The monomer composition containing the partial polymer becomes the state of slurry.In addition, in the monomer composition Unreacted monomer component suitably polymerize after the adhesive composition for preparing the curing type.

Known or usual polymerization can be used in the polymerization of the partial polymer.It is, for example, possible to use above-mentioned Polymerization initiator (such as Photoepolymerizationinitiater initiater) illustrated in " manufacturing method of acrylic polymer ", various, by the list Monomer component in body composition suitably polymerize.In addition, the aggregate rate of the partial polymer is for example adjusted to 5~15 matter % is measured, 7~10 mass % are preferably adjusted to.The aggregate rate of the partial polymer for example can be by grasping the monomer in advance The correlativity of the aggregate rate of the viscosity of composition and the partial polymer adjusts the monomer combination based on the correlativity The viscosity of object, is thus suitably adjusted.In addition, the partial polymer is wrapped eventually as a part of acrylic polymer Containing within the adhesive layer.

In addition, when using polyfunctional monomer as the monomer component for being used to form acrylic polymer, polyfunctional monomer May be fitted in the monomer composition before forming the partial polymer, also may be fitted to be formed it is described partially polymerized In the monomer composition after object.But from the acrylic polymer for forming cross-linking type, adhesive phase is reliably improved The viewpoints such as coherency consider, polyfunctional monomer is preferably cooperated to the monomer composition after forming the partial polymer In.

The adhesive composition of the curing type after preparation on the supporter appropriate such as substrate, release liner by applying Cloth is that stratiform etc. is applied.Then, curing process is implemented to the described adhesive composition (film) of stratiform.In addition, according to It needs before and after curing process, implements drying process.Described adhesive composition contains thermal polymerization to be caused as polymerization When agent, described adhesive composition is solidified by heating initiated polymerization.In contrast, described adhesive composition contains When Photoepolymerizationinitiater initiater is as polymerization initiator, described adhesive composition is caused by irradiation ultraviolet light isoreactivity energy-ray Polymerization reaction and solidify (photocuring).The irradiation of active energy beam can be from the single side of the adhesive composition (film) of stratiform Side carries out, and can also carry out from two surface sides.It is available to can be used in this implementation when thus described adhesive composition being solidified The adhesive phase of the double-sided adhesive sheet of mode.

In addition, known or usual oxygen can be appropriately carried out when being solidified (photocuring) using active energy beam Blocking method on the described adhesive composition (adhesive phase) of stratiform (for example, be bonded the branch appropriate such as release liner, substrate Support body carries out photocuring reaction in a nitrogen atmosphere) so that polymerization reaction not by the obstruction of the oxygen in air.

In addition, known or usual rubbing method can be used in the coating (coating) of described adhesive composition, can be used General coating machine is (for example, intaglio plate roll-coater, reversion roll-coater, contact roll-coater, immersion roll-coater, scraper apply Cloth machine, knife type coater, flush coater, comma coater, direct coating machine etc.).

As long as the adhesive group of above-mentioned curing type can be used in adhesive phase in addition, not damaging the purpose of the present application Close adhesive composition (for example, adhesive composition of the solvent type adhesive composition, emulsion-type) formation other than object.

Here, being illustrated to an example of the manufacturing method of adhesive phase (double-sided adhesive sheet).The manufacturing method be for The manufacturing method of the adhesive phase of shading purposes.

The manufacturing method includes: will be containing various of monomer ingredient, the monomer for being used to form acrylic polymer The adhesive combination of partial polymer, Photoepolymerizationinitiater initiater and colorant (such as carbon black) obtained from a part polymerization of ingredient Object is applied on supporter and forms the process (first step) of the film comprising described adhesive composition and to the film Irradiation light (such as ultraviolet light) makes the monomer component photopolymerization in the film and forms the acrylic polymer simultaneously And makes the curing of coating and obtain the process (the second step) of acrylic adhesive layer.

Moreover, in the manufacturing method, the use level of Photoepolymerizationinitiater initiater described in described adhesive composition relative to 100 mass parts of whole monomer components for being used to form the acrylic polymer are 0.3 mass parts or more, and the bonding The use level of colorant described in agent composition relative to whole 100 mass parts of monomer component be 1.5 below the mass, it is excellent It is selected as 1.0 below the mass.The use level of Photoepolymerizationinitiater initiater and the use level of colorant are this in described adhesive composition When the range of sample, Photoepolymerizationinitiater initiater can be fully activated using the light of irradiation in the second step, and can will be described Monomer component fully polymerize (photopolymerization).Therefore, it according to the manufacturing method, is capable of forming containing colorant and thickness ratio Biggish adhesive phase (such as 280 μm or more).In addition, even if the use level of colorant is such range, if adhesive The thickness of layer is big, then can fully reduce the transmission of visible light on the thickness direction of adhesive phase.

(thickness of adhesive phase)

Adhesive phase with a thickness of 280 μm or more, preferably 300 μm or more, more preferably 350 μm or more.Adhesive phase Thickness (μm) be such range when, even if being formed with height difference portion (such as protrusion), adhesive phase on the surface of adherend The shape to follow height difference portion can be deformed and be glued on adherend in a manner of seamlessly adhering to height difference portion.

The upper limit of the thickness of adhesive phase is not particularly limited, and can be suitably set according to purpose, such as preferably 1500 μ M hereinafter, more preferably 800 μm hereinafter, further preferably 600 μm or less.

(release liner)

The surface (adhesive surface) of adhesive phase can be protected until when using by release liner in double-sided adhesive sheet. Each adhesive surface of double-sided adhesive sheet can by respectively each self-shield of release liner, can also by be wound as it is scroll-like in the form of by A piece of release liner protects each adhesive surface.Release liner is used as the protection materials of adhesive surface, when pasting on adherend Removing.In addition, release liner also works as supporter in the case that double-sided adhesive sheet is no substrate double-sided adhesive sheet.Separately Outside, release liner may not necessarily be also set on both-sided adhesive face.

As release liner, usual peeling paper etc. can be used, be not particularly limited.As release liner, can make With for example: with lift-off processing layer substrate, comprising fluoropolymer-containing low adhesivity substrate, include the low of non-polar polymer Adhesivity substrate etc..It as the substrate with lift-off processing layer, can enumerate for example: utilize polysiloxane-based lift-off processing The stripping treatment agents such as agent, chain alkyl class stripping treatment agent, fluorine-containing type stripping treatment agent, molybdenum sulfide be surface-treated after base Material.As the fluoropolymer comprising in fluoropolymer-containing low adhesivity substrate, can enumerate for example: polytetrafluoroethyl-ne Alkene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoraoethylene-hexafluoropropylene copolymer, chlorine vinyl fluoride-inclined difluoro Ethylene copolymer etc..In addition, can enumerate for example as the non-polar polymer: olefine kind resin is (for example, polyethylene, poly- Propylene) etc..

As the substrate being surface-treated using stripping treatment agent, can enumerate for example: poly terephthalic acid second The polyester films such as diol ester；The olefine kind resins film such as polyethylene film, polypropylene film；Polyvinyl chloride film；Polyimides Film；The polyamide films such as nylon film；The plastic films such as rayon film；Or fine paper, Japan paper, brown paper, glass Paper, synthetic paper, face apply the stationeries such as paper.Wherein, from the viewpoint of processability, preferably polyester film or stationery, more preferably poly- pair Ethylene terephthalate.It is formed in addition, release liner can use known or customary way.In addition, the thickness of release liner Degree etc. is also not particularly limited.

(supporting base material)

Double-sided adhesive sheet can have supporting base material as needed.As the supporting base material, such as plastics can be used Film substrate (hereinafter referred to as plastic film substrate).The material of plastic film substrate is not particularly limited, and can enumerate for example: The acrylic resins such as the polyester resins such as polyethylene terephthalate, polymethyl methacrylate, polycarbonate, three second Acyl cellulose, polysulfones, polyarylate, polyimides, polyvinyl chloride, polyvinyl acetate, polyethylene, polypropylene, ethylene-propylene are total Polymers, trade name " ARTON (cyclic olefin quasi polymer, JSR manufacture) ", trade name " ZEONOR (cyclic olefin quasi polymer, Japan's auspicious father-in-law manufacture) " etc. the plastic materials such as cyclic olefins quasi polymer.In addition, these plastic materials can be used alone or It is used in combination.In addition, " supporting base material " be in use (stickup) double-sided adhesive sheet together with adhesive phase Paste the part on adherend.The release liner removed (when stickup) when the use of double-sided adhesive sheet is not included in the " branch In support group material ".

(shape)

The shape of double-sided adhesive sheet is not particularly limited, and can suitably set depending on the application.Tool as double-sided adhesive sheet Shape can enumerate the various shapes such as (band-like), strip for example band-like when vertical view, U-shaped (U shape), L shape, frame-shaped (ring-type).

(height difference absorbability)

The double-sided adhesive sheet of present embodiment has excellent height difference absorbability, even if the surface in adherend is formed with height Poor portion (such as protrusion), adhesive phase can also deform to follow the shape in height difference portion and seamlessly to adhere to height difference The mode in portion is glued on adherend.The adhesive phase of such double-sided adhesive sheet have appropriateness flexibility, can deform with Absorb the height difference portion on adherend.Therefore, the adhesive phase of the double-sided adhesive sheet of present embodiment also can be to allow its error Mode paste on the adherend for example comprising the low component of dimensional accuracy.

In addition, in the double-sided adhesive sheet of present embodiment, the height in the height difference portion on adherend that can be absorbed relative to The thickness (100%) of adhesive phase is preferably 35% hereinafter, more preferably 30% or less.

(other characteristics)

The bonding force (N/20mm) of the double-sided adhesive sheet (adhesive phase) of present embodiment is not particularly limited, such as preferably For 20N/20mm or more.Bonding force can be measured by the method recorded in aftermentioned embodiment.In addition, present embodiment is double Face bonding sheet (adhesive phase) has the characteristic (retentivity) being unlikely to be peel off long-time pastes on adherend.It keeps Power can be measured by the method recorded in aftermentioned embodiment.In addition, the double-sided adhesive sheet (adhesive phase) of present embodiment With the characteristics such as operational (operability), durability, resistance to falling impacts characteristic.

(purposes of double-sided adhesive sheet)

The double-sided adhesive sheet of present embodiment can will for example constitute the various components of portable electronic device or various Module uses when fixed.It as such portable electronic device, can enumerate for example: mobile phone, PHS (personal handhold phone System), smart phone, tablet computer (plate computer), mobile computer (mobile PC), portable data assistance (PDA), electricity The portable radio receiver such as sub- notepad, portable television or portable radio, portable game machine, portable audio The cameras such as player, digital camera, video camera of Portable image pickup type etc..

It as the specifically used mode of double-sided adhesive sheet, is not particularly limited, can enumerate for example: is fixed saturating on toward shell Mirror (especially glass lens), toward fixed display panel on shell, toward fixing the input such as sheet keyboard or touch panel on shell Device, being bonded of protection panels and shell of information display section, the fitting between shell, being bonded of shell and decorative sheet, Constitute various components or the fixation of module etc. of portable electronic device.

In addition, " lens " in this specification are to include the transparent body and unglazed refraction action for showing the refraction action of light Transparent body both sides concept.That is, " lens " in this specification also include the simple window panel of no refraction action.

In addition, can be enumerated as the component for being preferably used in portable electronic device for using double-sided adhesive sheet fixed Such as the plastics component for passing through the formation such as injection moulding.For example, double-sided adhesive sheet can be preferred for constituting portable electronic The fixation etc. of the optical component and plastics shell of equipment.

As the material for constituting the plastics component, it is not particularly limited, can enumerates for example: acrylic resin, Plastic material well known to polycarbonate resin, polyethylene terephthalate etc..In addition, double-sided adhesive sheet can also be suitble to use Adherend other than the plastics such as glass, metal (including metal oxide).

In addition, the double-sided adhesive sheet of present embodiment can be used in the device other than above-mentioned portable electronic device Fixed various parts or various modules.As the device other than the portable electronic device, can enumerate for example: display device (image display device), input unit etc..It as the display device, can enumerate for example: liquid crystal display device, organic EL (electroluminescent) display device, PDP (Plasmia indicating panel), Electronic Paper etc..In addition, as the input unit, Ke Yilie It illustrates such as: touch panel.

Embodiment

Hereinafter, the present invention is described in more detail based on embodiment.In addition, the present invention is not by any restriction of these embodiments.

[embodiment 1]

(production of slurry)

In 78 mass parts of 2-EHA (2EHA), the n-vinyl-2-pyrrolidone as monomer component (NVP) liquid monomer mixture (the monomer combination that 18 mass parts and 4 mass parts of acrylic acid 2- hydroxy methacrylate (HEA) mix Object) in, cooperate trade name " (2,2- dimethoxy -1, the 2- diphenylethanes-of IRGACURE 651 as Photoepolymerizationinitiater initiater 1- ketone) " (manufacture of BASF Amada Co., Ltd.) 0.05 mass parts and trade name " IRGACURE184 (1- hydroxycyclohexylphenyl first Ketone) " (manufacture of BASF Amada Co., Ltd.) 0.05 mass parts, then irradiate ultraviolet light until viscosity (BH viscosimeter, No. 5 rotors, 10rpm, 30 DEG C of measuring temperature) reach about 15Pas, to obtain obtained from a part polymerization comprising above-mentioned monomer component The slurry (2EHA/NVP/HEA=78/18/4) of partial polymer.

(production of adhesive composition A)

In 100 mass parts afore-mentioned slurries, acrylic acid (AA) 4 mass parts, 1,6- hexanediyl ester are added (HDDA) 0.12 mass parts, to obtain the mixture of the slurry.Add the light as additional quantity again in the mixture Trade name " IRGACURE 651 (2,2- dimethoxy -1,2- diphenylethane -1- ketone) " (BASF Japanese strain of polymerization initiator The manufacture of formula commercial firm) 0.7 mass parts.Then, 0.21 mass parts of carbon black are added again in the mixture as black pigment (black Colorant).They are sufficiently mixed, adhesive composition A is thus obtained.

In addition, adhesive composition A contain 104.12 mass parts be used to form whole monomers of acrylic polymer at Point.In whole monomer components, contain 8.7 mass parts monomers containing acidic-group (4 mass parts of carboxyl group-containing monomer, hydroxyl monomer 4.7 Mass parts), contain heterocyclic vinyl monomer containing 18 mass parts.

(production of double-sided adhesive sheet)

Described adhesive composition A is applied on the single side of release liner 30 being release-treated and makes the thickness after solidifying Degree is 400 μm, to obtain coating layer.Then, another release liner 40 is fitted into institute from the single-face side being release-treated It states on coating layer.In addition, using single side release-treated polyethylene terephthalate system as release liner 30,40 Substrate (trade name " MRF ", the manufacture of polyester film Co., Ltd., Mitsubishi；Or trade name " MRN ", Mitsubishi's polyester film strain formula meeting Society's manufacture).

It then, is 5W/cm through 30,40 pairs of the release liner coating layer irradiation illumination from two sides²Ultraviolet light 3 divide Clock solidifies the coating layer, to obtain 400 μm of thickness of adhesive phase 20.In addition, the generating source as ultraviolet light, makes " black light lamp (the Block ラ ッ Network ラ イ ト) " manufactured with Toshiba Corporation.In addition, the illumination of ultraviolet light (is passed through using UV detector Trade name " UVR-T1 " (Topcon Corporation's system, peak response: 350nm) measurement) it adjusts.

By above-mentioned mode, the double-sided adhesive sheet (no substrate double-sided adhesive sheet) 10 of embodiment 1 has been obtained (referring to figure 1)。

[embodiment 2]

(production of double-sided adhesive sheet)

Using adhesive composition A same as Example 1, the embodiment 2 of the adhesive phase with 350 μm of thickness is made Double-sided adhesive sheet (no substrate double-sided adhesive sheet).Specifically, adhesive composition A is applied to being stripped for release liner Make on the single side of processing after solidifying with a thickness of 350 μm, in addition to this, made the double of embodiment 2 similarly to Example 1 Face bonding sheet.

[embodiment 3]

(production of adhesive composition B)

In 100 mass parts afore-mentioned slurries (slurry similarly to Example 1), acrylic acid (AA) 4 mass parts and 1 are added, 0.12 mass parts of 6- hexanediyl ester (HDDA), to obtain the mixture of the slurry.In the mixture again Add the trade name " (2,2- dimethoxy -1,2- diphenyl second of IRGACURE 651 of the Photoepolymerizationinitiater initiater as additional quantity Alkane -1- ketone) " (manufacture of BASF Amada Co., Ltd.) 0.5 mass parts.Then, 0.5 mass of carbon black is added again in the mixture Part is used as black pigment (black colorant).They are sufficiently mixed, adhesive composition B is thus obtained.

In addition, adhesive composition B contain 104.12 mass parts be used to form whole monomers of acrylic polymer at Point.In whole monomer components, contain 8.7 mass parts monomers containing acidic-group (4 mass parts of carboxyl group-containing monomer, hydroxyl monomer 4.7 Mass parts), contain heterocyclic vinyl monomer containing 18 mass parts.

(production of double-sided adhesive sheet)

Using adhesive composition B, the double-sided adhesive sheet (nothing of the embodiment 3 of the adhesive phase with 300 μm of thickness is made Substrate double-sided adhesive sheet).Specifically, replacing adhesive composition A using adhesive composition B, and by adhesive composition B Be applied to make on the single side of release liner being release-treated after solidifying with a thickness of 300 μm, in addition to this, with embodiment 1 The double-sided adhesive sheet of embodiment 3 is similarly made.

[comparative example 1]

(production of double-sided adhesive sheet)

Using adhesive composition B similarly to Example 3, the comparative example 1 of the adhesive phase with 250 μm of thickness is made Double-sided adhesive sheet (no substrate double-sided adhesive sheet).Specifically, adhesive composition B is applied to being stripped for release liner Make on the single side of processing after solidifying with a thickness of 250 μm, in addition to this, made the double of comparative example 1 similarly to Example 3 Face bonding sheet.

[evaluation]

(total light transmittance)

For each double-sided adhesive sheet (only adhesive phase) of Examples 1 to 3 and comparative example 1, pass through side as shown below Method measures total light transmittance (%).Measurement result is as shown in table 1.

The double-sided adhesive sheet for having removed the state of a release liner is pasted into glass slide (trade name " S-1112 ", pine The manufacture of Lang Xiaozi industrial group, total light transmittance 91.8%, mist degree 0.4%), then another release liner is removed, is tried Test piece.Then, the total of the test film is measured using haze meter (trade name " HM-150 ", color technical research institute manufacture in village) Light rate.

(solvent insoluble component ratio)

Solvent is measured not by method as shown below for each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1 Molten component ratio (quality %) (only adhesive phase).Measurement result is as shown in table 1.

The adhesive phase (initial quality W1) of specified amount is impregnated into the ethyl acetate solution in regulation container, and It places one week at room temperature.Then, insoluble component is taken out from container, and measures the quality (W2) after being dried, by (W2/W1) × 100 are used as solvent insoluble component ratio (quality %).

(height difference absorbability)

Is evaluated by height difference and is inhaled by method as shown below for each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1 The property received.

Fig. 2 is the top view of the sample for evaluation group used when evaluating height difference absorbability, and Fig. 3 is the line A-A section view of Fig. 2 Figure.In Fig. 2 and Fig. 3,41 indicate that polycarbonate plate, 42 indicate that height difference adhesive tape, 43 indicate that window frame shape double-sided adhesive sheet, 44 indicate third Olefin(e) acid resin plate (acrylic resin lens), 45 indicate non-woven fabrics.Hereinafter, specifically describing the evaluation step of height difference absorbability Suddenly.

Firstly, by the double-sided adhesive sheet of Examples and Comparative Examples be cut into wide 1mm window frame shape (frame-shaped) (laterally: 60mm, It is longitudinal: 40mm), to obtain the double-sided adhesive sheet (hereinafter referred to as window frame shape double-sided adhesive sheet) of window frame shape.One evaluation is used Sample sets prepare 4 window frame shape double-sided adhesive sheets.Then, 4 acrylic acid resin plates (acrylic resin lens, laterally: 60mm, longitudinal direction: 40mm, thickness: 1mm) on by the acrylic acid resin plate carry out fringing in a manner of be bonded the window respectively Frame-shaped double-sided adhesive sheet.

Respectively prepare to be pasted with two pieces of height difference glue in the form of arranged side by side in parallel to each other with the acrylic acid resin plate The a piece of polycarbonate plate (PC plate) of band (width: 5mm, thickness: 100 μm).Then, four are crimped respectively on the polycarbonate plate A acrylic acid resin plate, so that the window frame shape double-sided adhesive sheet is Chong Die with the height difference band and in the window frame shape The inside of double-sided adhesive sheet configures non-woven fabric plate (width: 35mm, length: 55mm, thickness: 0.05mm), comments to obtain four The sample for evaluation group that valence is integrally formed with sample (referring to Fig. 2 and Fig. 3).Each acrylic acid resin plate is once round-trip in 2kg roller Under conditions of be crimped on polycarbonate plate.In addition, each sample for evaluation respectively has the height difference portion of the convex of 100 μm of height, Window frame shape double-sided adhesive sheet is overlapped in a manner of crossing in the height difference portion.The non-woven fabric plate is limited in each evaluation sample The inside of product.Due to the property that the changes colour when non-woven fabric plate has water suction, according to non-woven fabric plate, whether there is or not change colour can To confirm by visual observation, whether there is or not infiltrations inside each sample for evaluation.

Such sample for evaluation group is placed 30 minutes at standard state (temperature: 23 DEG C, humidity: 50%RH) and is carried out Aging.Then, it is based on IPX7 standard (JIS C0920/IEC60529), by sample for evaluation group in standard state (temperature: 23 DEG C, humidity: 50%RH) under submerged 30 minutes in the sink of depth of water 1m, and by confirming that the inside of each sample for evaluation has The height difference absorbability of double-sided adhesive sheet (window frame shape double-sided adhesive sheet) is evaluated without infiltration.

For each embodiment and comparative example, prepare two sample for evaluation groups, for amount to 8 evaluation samples confirm whether there is or not Infiltration.Based on this, whether there is or not infiltrations as a result, evaluating the height difference absorbability of double-sided adhesive sheet in each embodiment and comparative example.As commenting Valence is as a result, list the number for amounting to the evaluation sample not seeped water in 8 evaluation samples in table 1.

In addition, two pieces of height difference adhesive tapes are omitted for each embodiment and comparative example, in addition to this, by using with above-mentioned evaluation The same step of sample makes the sample for evaluation without height difference portion.Then, for not having the evaluation sample in the height difference portion Product evaluate that whether there is or not infiltrations in the same manner as the case where height difference portion with having.As evaluation result, is listed in table 1 and amount to 8 evaluation samples The number for the evaluation sample not seeped water in product.

(bonding force (to PC plate))

Each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1 is measured by method as shown below to poly- carbon The bonding force (N/20mm) of acid esters plate.Measurement result is as shown in table 1.

It is removed from both-sided adhesive on piece by a release liner, exposes an adhesive surface of adhesive phase.In the exposing Adhesive surface on, paste and 50 μm of thickness of PET film of lift-off processing is not carried out is usually coated to double-sided adhesive sheet.After lining Double-sided adhesive sheet cut out width 20mm as test film.As adherend, back and forth wiped using with the rag for being saturated with isopropanol Wipe the clean polycarbonate plate (PC plate) after being cleaned 10 times.Another release liner is removed from the test film, By being crimped onto the roller primary round-trip method of 2kg on the adherend test film.It will be crimped on adherend The test film of state is placed 30 minutes under 23 DEG C, the determination of the environment of 50%RH, then using cupping machine in tensile speed The peel strength (N/20mm) of measurement test piece under conditions of 300mm/ minutes, 180 ° of peel angle.

(bonding force (to SUS plate))

For each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1, the bonding force to stainless steel (SUS304B) plate is measured (N/20mm).Measuring method in addition to use stainless steel (SUS304B) plate replace polycarbonate plate (PC plate) other than with above-mentioned feelings Condition is same.The results are shown in Table 1.

(retentivity (60 DEG C))

For each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1,60 DEG C are evaluated by method as shown below Retentivity under environment.Evaluation result is as shown in table 1.

It is removed from both-sided adhesive on piece by a release liner, exposes an adhesive surface of adhesive phase.In the exposing Adhesive surface on, paste and 50 μm of thickness of PET film of lift-off processing is not carried out is usually coated to double-sided adhesive sheet.After lining Double-sided adhesive sheet cut out the size of width 10mm, length 50mm as test film.As adherend, using to be saturated with toluene Rag back and forth wipe the clean bakelite plate after being cleaned 10 times.Another release liner is shelled from the test film From by being crimped onto the roller of 2kg primary round-trip method on the adherend test film, to reach one end outer Side.The test film of the state on adherend (bakelite plate) will be crimped on after 40 DEG C are placed 30 minutes, by the bakelite plate 40 Dangle in the environment of DEG C, above-mentioned test film free end (from above-mentioned bakelite plate stretch out part) apply 500g load and It is placed 2 hours in the environment of 60 DEG C.The case where test film is fallen from adherend before from applying above-mentioned load by 2 hours Under, judge retentivity for " bad ".In addition, test film is also maintained at adherend after 2 hours from applying above-mentioned load In the case where upper, judge retentivity for " good ".In addition, listing the distance that test film deviates after 2 hours in table 1 (mm)。

(retentivity (80 DEG C))

Retentivity for each double-sided adhesive sheet of Examples 1 to 3 and comparative example 1, in the environment of 80 DEG C of evaluation.Evaluation side Method is identical as above-mentioned situation other than replacing in the environment of 60 DEG C in the environment of being set as 80 DEG C.The results are shown in Table 1.

Table 1

The double-sided adhesive sheet of embodiment 1 has 400 μm of thickness of adhesive phase.Acrylic in the adhesive phase Object contains the composition that 74.9 mass % (=78/104.12 × 100) derive from 2EHA (an example of (methyl) alkyl acrylate) Unit.In addition, the acrylic polymer contains 17.3 mass % (=18/104.12 × 100) from NVP (containing heterocycle An example of vinyl monomer) Component units.In addition, the acrylic polymer contains 3.84 mass % (=4/104.12 × 100) Component units of HEA (an example of monomer containing acidic-group and hydroxyl monomer) are derived from.In addition, the acrylic compounds Polymer contains 3.84 mass % (=4/104.12 × 100) from AA (the one of monomer containing acidic-group and carboxyl group-containing monomer Example) Component units.It is derived from addition, the acrylic polymer contains 0.12 mass % (=0.12/104.12 × 100) The Component units of HDDA (an example of polyfunctional monomer).In addition, the acrylic polymer contains 25 mass % from pole The Component units of property monomer.The solvent insoluble component ratio (%) of the adhesive phase of embodiment 1 is 73 mass %.

The double-sided adhesive sheet of embodiment 1 all evaluates sample in amounting to 8 evaluation samples as shown in table 1 and does not seep water.By This is it has been confirmed that the height difference absorbability of the adhesive phase of the double-sided adhesive sheet of embodiment 1 is excellent.

The double-sided adhesive sheet of embodiment 2 has 350 μm of thickness of adhesive phase.Acrylic in the adhesive phase Object derives from NVP's from the Component units of 2EHA, containing 17.3 mass % containing 74.9 mass % similarly to Example 1 Component units, containing 3.84 mass % from HEA Component units, containing 3.84 mass % from AA Component units, The Component units of HDDA are derived from containing 0.12 mass %.It is derived from addition, the acrylic polymer contains 25 mass % The Component units of polar monomer.But the solvent insoluble component ratio (%) of the adhesive phase of embodiment 2 is lower than embodiment 1, is 72 mass %.

The double-sided adhesive sheet of embodiment 2 also all evaluates sample in amounting to 8 evaluation samples as shown in table 1 and does not seep water. It is possible thereby to confirm, the height difference absorbability of the adhesive phase of the double-sided adhesive sheet of embodiment 2 is excellent.

The double-sided adhesive sheet of embodiment 3 has 300 μm of thickness of adhesive phase.Acrylic in the adhesive phase Object derives from NVP's from the Component units of 2EHA, containing 17.3 mass % containing 74.9 mass % similarly to Example 1 Component units, containing 3.84 mass % from HEA Component units, containing 3.84 mass % from AA Component units, The Component units of HDDA are derived from containing 0.12 mass %.It is derived from addition, the acrylic polymer contains 25 mass % The Component units of polar monomer.But the solvent insoluble component ratio (%) of the adhesive phase of embodiment 3 is lower than 1 He of embodiment Embodiment 2 is 68 mass %.

4 evaluation samples do not seep water the double-sided adhesive sheet of embodiment 3 in amounting to 8 evaluation samples as shown in table 1, still Remaining 4 result is infiltration.It can be said that the height difference absorbability of the adhesive phase of the double-sided adhesive sheet of embodiment 3 is than real It applies example 1 and embodiment 2 is poor, but be an advantage over aftermentioned comparative example 1.

The double-sided adhesive sheet of comparative example 1 has 250 μm of thickness of adhesive phase.Acrylic in the adhesive phase Object derives from NVP's from the Component units of 2EHA, containing 17.3 mass % containing 74.9 mass % similarly to Example 1 Component units, containing 3.84 mass % from HEA Component units, containing 3.84 mass % from AA Component units, The Component units of HDDA are derived from containing 0.12 mass %.It is derived from addition, the acrylic polymer contains 25 mass % The Component units of polar monomer.But the solvent insoluble component ratio (%) of the adhesive phase of comparative example 1 is lower than 1 He of embodiment Embodiment 2 is 68 mass %.

The double-sided adhesive sheet of comparative example 1 has obtained all evaluating sample infiltration in amounting to 8 evaluation samples as shown in table 1 Result.It is possible thereby to confirm, the adhesive phase of the double-sided adhesive sheet of comparative example 1 does not have height difference absorbability.

In addition, for bonding force, retentivity and waterproof test without height difference portion, Examples 1 to 3 and comparative example 1 are appointed One double-sided adhesive sheet obtains good result.

Claims (5)

1. a kind of double-sided adhesive sheet, for the fixed component for constituting portable electronic device, wherein

The double-sided adhesive sheet has acrylic adhesive layer, and the acrylic adhesive layer contains acrylic polymer As basic polymer, the acrylic polymer contain 9~30 mass % from polar monomer Component units and (methyl) alkyl acrylate for the linear or branched alkyl group for being 1~20 with carbon atom number is derived from containing 50 mass % or more Component units,

The acrylic polymer contain 2 mass % or more and 4 mass % or less from carboxyl group-containing monomer Component units, And 10 it is more than mass % from the Component units containing heterocyclic vinyl monomer as the composition from polar monomer Unit,

The acrylic adhesive layer with a thickness of 280 μm or more.

2. double-sided adhesive sheet as described in claim 1, wherein the acrylic polymer contains the 2 above sources mass % The Component units of polar monomer are derived from as described in the Component units of hydroxyl monomer.

3. double-sided adhesive sheet as described in claim 1, wherein the acrylic polymer contain from tool there are two with The Component units of the polyfunctional monomer of upper polymerizable functional group.

4. double-sided adhesive sheet as described in claim 1, wherein the transmission on the thickness direction of the acrylic adhesive layer Rate is 5% or less.

5. a kind of manufacturing method of double-sided adhesive sheet is double-sided adhesive sheet described in any one of manufacturing claims 1~4 Method, wherein

The described method includes:

A part polymerization containing the various of monomer ingredient, the monomer component for being used to form acrylic polymer is obtained Partial polymer, Photoepolymerizationinitiater initiater and colorant adhesive composition be applied on supporter and formed comprising described viscous The process of the film of mixture composite；With

To the film irradiation light, makes the monomer component photopolymerization in the film and form the acrylic polymer And the process for making the curing of coating and obtaining acrylic adhesive layer；

The use level of Photoepolymerizationinitiater initiater described in described adhesive composition is formed relative to the acrylic 100 mass parts of whole monomer components of object are 0.3 mass parts or more, and colorant described in described adhesive composition is matched Resultant is 0.25 below the mass relative to whole 100 mass parts of monomer component.