TW202100695A - Adhesive tape - Google Patents

Abstract

Provided are: an adhesive agent in which a reduction in adhesive strength is suppressed when the adhesive agent comes into contact with an oil component or an alcohol component; and an adhesive tape containing the adhesive agent. This adhesive tape includes a substrate and an adhesive layer disposed on at least one side of the substrate. The adhesive layer contains an adhesive agent that exhibits adhesive properties upon pressure bonding. The adhesive agent contains an acrylic polymer having an acid functional group and a crystalline resin having a melting point of 25 DEG C or higher. The haze value of the adhesive tape is 20% or less.

Description

Adhesive tape

The present invention relates to an adhesive tape.

Previously, adhesive tapes or double-sided tapes were used for surface protection, insulation protection, and member bonding or fixing by attaching to various members and utilizing their functions. However, when it is used for touching with human hands, it is easy to adhere to secretions such as sebum or hand dirt through fingertips, cosmetics or hairdressing agents, moisturizers, sunscreens and other chemicals, or foods, etc. Oil. In addition, in the case of use in a living environment, not only the oil is easily adhered to components, but also the alcohol components such as ethanol contained in perfumes, sterilization sheets, and disinfection alcohols are also easily adhered components. In such a use form, if components such as oils or alcohol components come into contact with the adhesive layer of the adhesive sheet, the adhesive force may decrease, causing problems such as swelling and peeling. [Prior Technical Literature] [Patent Literature]

Patent Document 1: Japanese Patent Laid-Open No. 2009-215355 Patent Document 2: Japanese Patent Laid-Open No. 2013-100485 Patent Document 3: Japanese Patent Laid-Open No. 2017-132911

[The problem to be solved by the invention]

The present invention was made in order to solve the previous problems, and its object is to provide an adhesive tape that suppresses the decrease in adhesive force when it comes into contact with oil or alcohol components. [Technical means to solve the problem]

The adhesive tape of the present invention is provided with a substrate and an adhesive layer disposed on at least one side of the substrate, and the adhesive layer includes an adhesive that exhibits adhesion by pressure bonding, and the adhesive includes an acid Acrylic polymers with functional groups and crystalline resins with a melting point of 25°C or higher, the haze value of the adhesive tape is 20% or less. In one embodiment, the adhesive tape exhibits adhesiveness by heating. In one embodiment, the above-mentioned acrylic polymer having an acid functional group contains a structural unit a derived from an alkyl (meth)acrylate having a linear or branched alkyl group having a carbon number of 4 or more. In one embodiment, the content ratio of the structural unit a is 50 parts by weight or more relative to 100 parts by weight of the acrylic polymer having an acid functional group. In one embodiment, the crystalline resin is a polyolefin resin. In one embodiment, the above-mentioned polyolefin resin is a maleic anhydride modified polyolefin resin, a maleic acid modified polyolefin resin, or an acrylic acid modified polyolefin resin. In one embodiment, the adhesive includes a C5 series petroleum resin and/or a C9 series petroleum resin. In one embodiment, the substrate is selected from polyacrylate, polyurethane, polyimide, polyaramide, polyamide, ethylene-vinyl alcohol copolymer, polyetherimide, At least one of polyvinylidene fluoride, polyester, polypropylene, polyethylene, and polyphenylene sulfide is formed. In one embodiment, a release film is provided on the opposite side of the adhesive layer from the base material. In one embodiment, the adhesive layer is arranged on both sides of the substrate. [Effects of Invention]

According to the present invention, it is possible to provide an adhesive tape in which the decrease in adhesive force when it comes into contact with oil or alcohol components is suppressed. In addition, the adhesive tape of the present invention exhibits excellent adhesion to both a metallic adherend and a non-metal adherend. In addition, the adhesive tape of the present invention is excellent in heat resistance and chemical resistance, and can exhibit excellent adhesiveness and bonding properties in various applications. Furthermore, the adhesive tape of the present invention has the characteristics that the haze value is small, and the haze value changes less with time. This kind of adhesive tape has the advantages of excellent visibility through the adhesive tape and easy positioning of the adhesive tape.

＜＜Adhesive tape＞＞ Fig. 1 is a schematic cross-sectional view of an adhesive tape according to an embodiment of the present invention. The adhesive tape 100 includes a substrate 10 and an adhesive layer 20 disposed on at least one side (both sides in the example of the figure) of the substrate 10. Although not shown, the adhesive tape may be provided with a release film on the outer side of the adhesive layer (that is, the surface of the adhesive layer opposite to the substrate) in order to protect the adhesive surface during the period before use.

The adhesive layer constituting the above-mentioned adhesive tape exhibits adhesiveness by pressure bonding. The adhesive tape (substantially an adhesive layer) may be an adhesive tape that exhibits adhesiveness at room temperature (25°C), or an adhesive tape that exhibits adhesiveness by heating. The adhesive tape that exhibits adhesiveness by heating can exhibit adhesiveness after being heated and cooled to room temperature.

The adhesive constituting the adhesive layer includes an acrylic polymer having an acid functional group and a crystalline resin having a melting point of 25°C or higher. In the present invention, by using the acrylic polymer having an acid functional group in combination with the above crystalline resin, excellent heat resistance and chemical resistance can be obtained, and the decrease in adhesion when contact with oil or alcohol is suppressed Adhesive. The adhesive tape obtained by using this adhesive can be preferably used for the joining of metal materials and metal materials, the joining of non-metal materials and non-metal materials, and the joining of metal materials and non-metal materials.

Furthermore, in the present invention, by using an acrylic polymer with an acid functional group and a crystalline resin with a melting point of 25°C or higher, it can be formed by mixing dissimilar materials with less light scattering and higher haze value. Small adhesive layer. The adhesive tape obtained by using this adhesive has the advantages of excellent visibility of the sensor through the adhesive tape, and easy positioning of the adhesive tape.

When the adhesive layer of the adhesive tape of the present invention is attached to an aluminum plate, the adhesive force at 25°C is preferably 0.5 N/10 mm or more, more preferably 0.8 N/10 mm-20 N/10 mm, and more preferably It is 1 N/10 mm～10 N/10 mm. In this manual, the so-called adhesive force refers to the adhesive force measured by the method in accordance with JIS Z 0237:2000, the adhesive tape is attached to the aluminum plate with 1 round trip of a 2 kg roller and placed at 25°C After 30 minutes, the adhesive tape was peeled off under the conditions of a peeling angle of 180° and a peeling speed (tensile speed) of 300 mm/min for measurement. Furthermore, when the adhesive tape is an adhesive tape that exhibits adhesiveness by heating, the adhesive tape displays adhesiveness at a temperature (for example, 130°C, 0.4 MPa, 5 minutes) to adhere The adhesive force measured after the tape and the aluminum plate are cooled to 25°C is equivalent to the above-mentioned adhesive force.

The haze value of the adhesive tape is 20% or less, preferably 18% or less, more preferably 10% or less, further preferably 8% or less, and particularly preferably 5% or less. The smaller the haze value of the adhesive tape, the better, and the lower limit is, for example, 1%. The haze value of the adhesive tape can be adjusted by adjusting the type of substrate, the structure of the acrylic polymer with acid functional groups (for example, monomer components, molecular weight), the structure of the crystalline resin, the acrylic polymer with acid functional groups, and The content ratio of the crystalline resin is adjusted.

When the above-mentioned adhesive tape is stored at an ambient temperature of 5°C for 72 hours, the change rate of the fog value of the adhesive tape ((fog value after storage for 72 hours-initial fog value)/initial fog value) is preferably 20% Below, 16% or less is more preferable, 10% or less is still more preferable, and 8% or less is particularly preferable. The smaller the rate of change is, the better, and its lower limit is, for example, 0.1%.

The thickness of the adhesive tape is preferably 5 μm to 200 μm, more preferably 15 μm to 150 μm, and still more preferably 30 μm to 100 μm.

＜Adhesive layer＞ As described above, the adhesive layer is composed of an adhesive containing an acrylic polymer having an acid functional group and a crystalline resin with a melting point of 25°C or higher.

The thickness of the adhesive layer is preferably 1 μm to 100 μm, more preferably 3 μm to 80 μm, and still more preferably 5 μm to 50 μm.

The haze value of the adhesive layer is preferably 20% or less, more preferably 18% or less, still more preferably 10% or less, particularly preferably 8% or less, and most preferably 5% or less. The smaller the haze value of the adhesive layer, the better, and the lower limit is, for example, 1%.

When the above-mentioned adhesive tape is stored at an ambient temperature of 5°C for 72 hours, the change rate of the haze value of the adhesive layer constituting the adhesive tape ((haze value after storage 72-initial haze value)/initial haze value) is compared It is preferably 20% or less, more preferably 16% or less, still more preferably 10% or less, and particularly preferably 8% or less. The smaller the rate of change is, the better, and its lower limit is, for example, 2%.

The probe viscosity value of the adhesive layer at 25° C. is preferably 500 g or less, more preferably 400 g or less, still more preferably 340 g or less, and particularly preferably 10 g to 300 g. The measuring method of the probe viscosity value is described below.

(Acrylic polymer with acid functional group) As the acrylic polymer having an acid functional group, for example, those containing one or more structural units derived from alkyl (meth)acrylates and structural units derived from monomers having acid functional groups can be cited Acrylic polymer.

In the above-mentioned adhesive, the content ratio of the acrylic polymer with acid functional group relative to 100 parts by weight of the solid content in the adhesive is preferably 7 parts by weight to 95 parts by weight, more preferably 15 parts by weight to 90 parts by weight Parts by weight are more preferably 20 parts by weight to 85 parts by weight, and particularly preferably 40 parts by weight to 85 parts by weight. The content of the acrylic polymer having an acid functional group can be set to an appropriate amount according to adhesiveness and the like. Furthermore, in addition to the acrylic polymer having an acid functional group, the above-mentioned adhesive may include an acrylic polymer without an acid functional group, or may not include an acrylic polymer without an acid functional group.

The content ratio of the structural unit derived from the above-mentioned alkyl (meth)acrylate relative to 100 parts by weight of the acrylic polymer having an acid functional group is preferably 50 parts by weight to 99 parts by weight, more preferably 70 parts by weight to 98 parts by weight, more preferably 80 parts by weight to 98 parts by weight.

Preferably, the above-mentioned alkyl (meth)acrylate has a linear or branched carbon number of 1-24 (more preferably 3-20, still more preferably 4-12, and particularly preferably 4-8).之alkyl.

Examples of the above-mentioned alkyl (meth)acrylate include: methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, (meth) ) Amyl acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, nonyl (meth)acrylate, decyl (meth)acrylate, (meth)acrylic acid Eicosyl ester and so on.

In one embodiment, the above-mentioned acrylic polymer having an acid functional group contains a linear or branched alkyl group derived from a carbon number of 4 or more (preferably 4-12, more preferably 4-8) The structural unit a of the alkyl (meth)acrylate, the content ratio of the structural unit a relative to 100 parts by weight of the acrylic polymer with acid functional groups is 50 parts by weight or more (preferably 50 parts by weight to 99 parts by weight Parts, more preferably 70 parts by weight to 98 parts by weight, still more preferably 80 parts by weight to 98 parts by weight). If an acrylic polymer containing a specific amount of the structural unit a and having an acid functional group is used, excellent heat resistance and chemical resistance can be obtained, and adhesion with reduced adhesion when contacted with oil or alcohol components is suppressed Agent.

In one embodiment, an alkyl (meth)acrylate having a branched alkyl group is used as the alkyl (meth)acrylate. If an alkyl (meth)acrylate having a branched alkyl group is used, an adhesive tape with excellent chemical resistance can be obtained. The carbon number of the branched alkyl group is preferably 4 or more, more preferably 4-12, and still more preferably 4-8. The alkyl (meth)acrylate having a linear alkyl group and the alkyl (meth)acrylate having a branched alkyl group may also be used in combination. In addition, as the alkyl (meth)acrylate, an alkyl (meth)acrylate having a branched alkyl group may be used alone.

In one embodiment, in the acrylic polymer having an acid functional group, the content ratio of the structural unit derived from the alkyl (meth)acrylate having a branched alkyl group is relative to the content of the structural unit derived from the (meth)acrylic acid 100 parts by weight of the structural unit of the alkyl ester (that is, 100 parts by weight of the total amount of the alkyl (meth)acrylate having a linear alkyl group and the alkyl (meth)acrylate having a branched alkyl group) , Preferably 50 parts by weight to 100 parts by weight, more preferably 70 parts by weight to 100 parts by weight, and still more preferably 80 parts by weight to 100 parts by weight.

Examples of alkyl (meth)acrylates having branched alkyl groups include isobutyl (meth)acrylate, second butyl (meth)acrylate, tertiary butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, isodecyl (meth)acrylate, 2-ethylbutyl (meth)acrylate , 2-methylbutyl (meth)acrylate, etc. Among them, 2-ethylhexyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate, or isodecyl (meth)acrylate is preferred, and (methyl) ) 2-Ethylhexyl acrylate. If 2-ethylhexyl (meth)acrylate is used, an adhesive can be obtained that suppresses the decrease in adhesive force when it comes into contact with oil or alcohol components.

As an acid functional group which the acrylic polymer which has an acid functional group has, a carboxyl group, an acid anhydride group, a phosphoric acid group, a sulfonic acid group etc. are mentioned, for example. Therefore, as a monomer having the above-mentioned acid functional group, for example, a carboxyl group-containing monomer, an acid anhydride group-containing monomer, a phosphoric acid group-containing monomer, a sulfonic acid group-containing monomer, and the like can be cited. Among them, carboxyl group-containing monomers are preferred. If a carboxyl group-containing monomer is used, it has the following characteristics: easy to express adhesion to metal plates, easy to copolymerize with other acrylic monomers in terms of design and production, and easy to form polymers by copolymerization Cross-linked.

As said carboxyl group-containing monomer, (meth)acrylic acid, carboxyethyl acrylate, carboxypentyl acrylate, itaconic acid, maleic acid, fumaric acid, crotonic acid, etc. are mentioned, for example. Among them, acrylic acid is preferred.

The content ratio of the structural unit derived from the monomer having an acid functional group relative to 100 parts by weight of the acrylic polymer having an acid functional group is preferably 1.5 to 20 parts by weight, more preferably 1.8 to 15 parts by weight Parts by weight are more preferably 2 parts by weight to 10 parts by weight.

The acrylic polymer with acid functional group can also be used for modification of cohesive force, heat resistance, crosslinking property, etc., and if necessary, it may be derived from the alkyl (meth)acrylate and/or has acid functional group. The monomer is the structural unit of other monomers copolymerized. As such other monomers, for example, hydroxyethyl (meth)acrylate, hydroxypropyl (meth)acrylate, hydroxybutyl (meth)acrylate, hydroxyhexyl (meth)acrylate, (methyl) ) Hydroxy-containing monomers such as hydroxyoctyl acrylate, hydroxydecyl (meth)acrylate, hydroxylauryl (meth)acrylate, and (4-hydroxymethylcyclohexyl)methyl methacrylate; (meth)acrylic acid Amine, N,N-dimethyl(meth)acrylamide, N-butyl(meth)acrylamide, N-methylol(meth)acrylamide, N-methylolpropane (meth)acrylamide, (N-substituted) amide-based monomers such as acrylamide; aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, (meth)acrylic acid third Amino alkyl (meth)acrylate monomers such as butylaminoethyl; methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate and other (meth)acrylate alkoxy Alkyl alkyl ester monomer; N-cyclohexyl maleimide, N-isopropyl maleimide, N-lauryl maleimide, N-phenyl cis Butylene diimidimine and other maleic imine monomers; N-methyl iconimidin, N-ethyl iconimines, N-butyl iconimines, N- Ikonimines such as octyl Ikonimines, N-2-ethylhexyl Ikonimines, N-cyclohexyl Ikonimines, N-Lauryl Ikonimines; N-(meth)acryloyloxymethylene succinimide, N-(meth)acryloyl-6-oxyhexamethylene succinimide, N-(meth)propylene Amino-8-oxyoctamethylene succinylidene-based monomers such as succinylidene imine; vinyl acetate, vinyl propionate, N-vinylpyrrolidone, methylvinylpyrrolidone , Vinyl pyridine, vinyl piperidone, vinyl pyrimidine, vinyl piperidine, vinyl pyridine, vinyl pyrrole, vinyl imidazole, vinyl azole, vinyl pyridine, N-vinyl carboxyamide Vinyl monomers such as styrene, α-methylstyrene, N-vinylcaprolactam; cyanoacrylate monomers such as acrylonitrile and methacrylonitrile; glycidyl (meth)acrylate, etc. Acrylic monomers containing epoxy groups; polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, methoxy glycol (meth) acrylate, methoxy polypropylene glycol (meth) Glycol acrylate monomers such as acrylate; tetrahydrofurfuryl (meth)acrylate, fluorine (meth)acrylate, polysiloxane (meth)acrylate, etc. have heterocycles, halogen atoms, and silicon atoms Acrylic monomers such as hexamethylene glycol di(meth)acrylate, (poly)ethylene glycol di(meth)acrylate, (poly)propylene glycol di(meth)acrylate, neopentyl glycol two (Meth) acrylate, pentaerythritol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, epoxy Multifunctional monomers such as acrylate, polyester acrylate, and urethane acrylate; olefin-based monomers such as isoprene, butadiene, and isobutylene; vinyl ether, etc. Vinyl ether monomers, etc. These monomer components can be used individually or in combination of 2 or more types.

The content ratio of the structural unit derived from the above-mentioned other monomers is preferably 20 parts by weight or less, more preferably 10 parts by weight or less, and more preferably 5 parts by weight relative to 100 parts by weight of the acrylic polymer having acid functional groups the following.

The weight average molecular weight of the above-mentioned acrylic polymer having acid functional groups is preferably 300,000 to 2 million, more preferably 500,000 to 1.5 million. The weight average molecular weight can be measured by GPC (Gel Permeation Chromatography) (solvent: THF (Tetrahydrofuran)).

(Crystalline resin) As described above, the adhesive of the present invention contains a crystalline resin. The so-called crystalline resin refers to a resin that has a clear endothermic peak (with a half-value width within 15°C) in the differential calorie curve measured by a differential scanning calorimeter (DSC).

In the adhesive, the content ratio of the crystalline resin relative to 100 parts by weight of the solid content in the adhesive is preferably 3 parts by weight to 90 parts by weight, more preferably 10 parts by weight to 85 parts by weight, and more preferably 15 parts by weight to 80 parts by weight.

The melting point of the above crystalline resin is 25°C or higher, more preferably 40°C or higher, still more preferably 60°C to 120°C, and particularly preferably 60°C to 100°C. If it is in such a range, an adhesive that is excellent in heat resistance and chemical resistance, and reduces the adhesive force when it comes into contact with oil or alcohol components can be obtained. The melting point can be determined by differential scanning calorimetry (DSC).

The weight average molecular weight of the crystalline resin is preferably 50,000 to 1.5 million, more preferably 70,000 to 1 million.

The crystallinity of the above-mentioned crystalline resin is preferably 10% or more, more preferably 20% or more. Typically, the degree of crystallinity can be determined by differential scanning calorimetry (DSC).

In one embodiment, the crystalline resin is a polyolefin resin. As the polyolefin resin, for example, ethylene homopolymer, ethylene-propylene copolymer, ethylene-1-butene copolymer, ethylene-1-hexene copolymer, ethylene-1-octene copolymer, ethylene -1-heptene copolymer, ethylene-1-octene copolymer, ethylene-1-nonene copolymer, ethylene-1-decene copolymer, ethylene-1-undecene copolymer, ethylene-1- Dodecene copolymer, ethylene-1-tridecene copolymer, ethylene-1-tetradecene copolymer, ethylene-1-pentadecene copolymer, ethylene-1-hexadecene copolymer , Ethylene-1-heptadecene copolymer, ethylene-1-octadecene copolymer, ethylene-1-nonadecene copolymer, ethylene-1-eicosene copolymer and other ethylene-α-olefins Copolymers; ethylene-vinyl ester copolymers such as ethylene-vinyl acetate copolymer and ethylene-vinyl propionate copolymer; ethylene-methyl methacrylate copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate Ethylene-unsaturated carboxylic acid alkyl ester copolymers such as copolymers and ethylene-butyl acrylate copolymers; propylene-based resins, etc.

In one embodiment, a crystalline polypropylene resin is used as the crystalline resin. The crystalline polypropylene resin may be a homopolymer or a copolymer obtained from propylene and a monomer copolymerizable with propylene. As monomers copolymerizable with propylene, for example, ethylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene, 4-methyl-1-pentene, Α-olefins such as 3-methyl-1-pentene, etc. In the crystalline polypropylene resin, the content ratio of the propylene-derived structural unit is preferably 60 mol% to 99 mol%, more preferably 65 mol% to 99 mol%, and still more preferably 70 mol% Ear%～99mol%. In the crystalline polypropylene resin, the content ratio of the structural unit derived from α-olefin is preferably 1 mol% to 15 mol%, and more preferably 1 mol% to 10 mol%.

In one embodiment, a modified polyolefin-based resin is used as the crystalline resin. If a modified polyolefin resin is used, the phase separation between the crystalline resin and the acrylic polymer having an acid functional group is suppressed, there is less exudation, and an adhesive layer with excellent transparency can be formed. As the modified polyolefin-based resin, maleic anhydride-modified polyolefin-based resin, maleic acid-modified polyolefin-based resin, acrylic-modified polyolefin-based resin, etc. can be preferably used. Specifically, the above-mentioned polyolefin resin is modified by maleic anhydride, modified with maleic acid, or modified with acrylic acid. Among them, maleic anhydride polyolefin resin is preferred, and maleic anhydride modified propylene resin is more preferred. Specific examples of maleic anhydride-modified propylene resins include resins obtained by modifying the above-mentioned crystalline polypropylene resins with maleic anhydride. The modification rate of the modified polyolefin resin is preferably 1% by weight to 5% by weight, more preferably 1.5% by weight to 2% by weight.

(additive) The above-mentioned adhesive may optionally contain any appropriate additives. Examples of the additives include: crosslinking agents, adhesion-imparting agents, plasticizers (for example, trimellitate-based plasticizers, pyromellitic acid-based plasticizers), pigments, dyes, and fillers , Anti-aging agents, conductive materials, ultraviolet absorbers, light stabilizers, stripping regulators, softeners, surfactants, flame retardants, antioxidants, solvents, etc. In addition, the above-mentioned adhesive may contain any suitable solvent.

As the above-mentioned adhesive imparting agent, any appropriate adhesive imparting agent can be used. As the adhesion imparting agent, for example, an adhesion imparting resin can be used. Specific examples of adhesion-imparting resins include: rosin-based adhesion-imparting resins (for example, unmodified rosin, modified rosin, rosin-phenol resin, rosin ester resin, etc.), terpene-based adhesion-imparting resins (for example, terpene Olefin resins, terpene phenol resins, styrene-modified terpene resins, aromatic modified terpene resins, hydrogenated terpene resins), hydrocarbon-based adhesion-imparting resins (for example, aliphatic hydrocarbon resins, aliphatic Cyclic hydrocarbon resin, aromatic hydrocarbon resin (for example, styrene resin, xylene resin, etc.), aliphatic-aromatic petroleum resin, aliphatic-alicyclic petroleum resin, hydrogenated hydrocarbon resin, smoke Carb-based resins, lavender-indene resins, etc.), phenolic adhesion-imparting resins (for example, alkylphenol resins, xylene formaldehyde resins, phenolic resins, novolacs, etc.), ketone-based adhesion-imparting resins , Polyamide-based adhesion imparting resin, epoxy-based adhesion imparting resin, elastic system adhesion imparting resin, etc.

In one embodiment, the above-mentioned adhesive uses a C5 series petroleum resin and/or a C9 series petroleum resin as an adhesion imparting agent. If these adhesive imparting agents are used, an adhesive having excellent sebum resistance and alcohol resistance can be obtained.

The softening point of the adhesion imparting agent is preferably 70°C to 200°C, more preferably 80°C to 190°C. If it is in this range, an adhesive layer with the storage elastic modulus and loss elastic modulus appropriately adjusted can be obtained.

The content ratio of the adhesion imparting agent is 100 parts by weight of the total amount of the acrylic polymer having acid functional groups and the crystalline resin having a melting point of 25°C or higher, preferably 5 parts by weight to 50 parts by weight, more preferably 10 Parts by weight ~ 40 parts by weight.

Examples of the crosslinking agent include isocyanate-based crosslinking agents, epoxy-based crosslinking agents, melamine-based crosslinking agents, peroxide-based crosslinking agents, and urea-based crosslinking agents, metal alkoxides Material crosslinking agent, metal chelate crosslinking agent, metal salt crosslinking agent, carbodiimide crosslinking agent, azoline crosslinking agent, aziridine crosslinking agent, amine series Crosslinking agent, etc. Among them, an isocyanate-based crosslinking agent, an epoxy-based crosslinking agent, or a metal chelate-based crosslinking agent is preferred.

Specific examples of the above-mentioned isocyanate-based crosslinking agent include: lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; cyclopentyl diisocyanate, cyclohexyl diisocyanate, isophor Alicyclic isocyanates such as ketone diisocyanate; aromatic isocyanates such as 2,4-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate; trimethylolpropane/toluene diisocyanate Isocyanate trimer adduct (manufactured by Nippon Polyurethane Industry, trade name "Coronate L"), trimethylolpropane/hexamethylene diisocyanate trimer adduct (manufactured by Nippon Polyurethane Industry, trade name "Coronate L") Coronate HL"), isocyanurate body of hexamethylene diisocyanate (manufactured by Nippon Polyurethane Industry, trade name "Coronate HX") and other isocyanate adducts. The content of the isocyanate-based crosslinking agent can be set to any appropriate amount according to the required adhesive force and elastic modulus, relative to the total amount of the acrylic polymer with acid functional groups and the crystalline resin with a melting point of 25°C or higher 100 parts by weight, typically 0.1 to 20 parts by weight, more preferably 0.5 to 10 parts by weight.

Examples of the epoxy-based crosslinking agent include: N,N,N',N'-tetraglycidyl metaxylylenediamine, diglycidylaniline, 1,3-bis(N,N-glycidyl Glycerylaminomethyl)cyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd., trade name "Tetrad C"), 1,6-hexanediol diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Epolight 1600") ), neopentyl glycol diglycidyl ether (manufactured by Kyoeisha Chemical Company, trade name "Epolight 1500NP"), ethylene glycol diglycidyl ether (manufactured by Kyoeisha Chemical Company, trade name "Epolight 40E"), propylene glycol Diglycidyl ether (manufactured by Kyoeisha Chemical Co., Ltd., trade name "Epolight 70P"), polyethylene glycol diglycidyl ether (manufactured by Nippon Oil & Fat Co., Ltd., trade name "Epiol E-400"), polypropylene glycol diglycidyl ether (Manufactured by Nippon Oil & Fat Co., Ltd., trade name "Epiol P-200"), sorbitol polyglycidyl ether (manufactured by Nagase ChemteX, trade name "DENACOL EX-611"), glycerol polyglycidyl ether (manufactured by Nagase ChemteX, Trade name "DENACOL EX-314"), pentaerythritol polyglycidyl ether, polyglycerol polyglycidyl ether (manufactured by Nagase ChemteX, trade name "DENACOL EX-512"), sorbitan polyglycidyl ether, trimethylol Propane polyglycidyl ether, diglycidyl adipate, diglycidyl phthalate, tris(2-hydroxyethyl) isocyanurate triglycidyl, resorcinol diglycidyl ether, bisphenol S-Diglycidyl ether, epoxy resin having two or more epoxy groups in the molecule, etc. The content of epoxy crosslinking agent can be set to any appropriate amount according to the required adhesive force and elastic modulus, relative to the total of acrylic polymer with acid functional group and crystalline resin with a melting point of 25°C or higher The amount is 100 parts by weight, typically 0.01 parts by weight to 10 parts by weight, more preferably 0.03 parts by weight to 5 parts by weight.

As the metal chelate crosslinking agent, for example, a metal chelate compound in which the metal atom is aluminum, zirconium, titanium, zinc, iron, tin, or the like can be used. Among them, aluminum chelate compounds or titanium chelate compounds are preferred.

As the aluminum chelate compound, for example, diisopropoxy aluminum monoacetate oleyl ester, monoisopropoxy aluminum diacetate oleyl ester, monoisopropoxy aluminum monooleate monoacetate acetic acid Ethyl acetate, diisopropoxy aluminum monoacetate lauryl acetate, diisopropoxy aluminum monoacetate stearyl acetate, diisopropoxy aluminum monoacetate isostearyl acetate, monoisopropoxy Aluminum Mono-N-Lauryl-β-Aluminum Hydride (alanate) Monoacetyl Lauryl Acetate, Tris (Acetylpyruvate) Aluminum, Acetylpyruvate Aluminum Double (Acetyl Acetate), Monoacetate Aluminum pyruvate bis(isobutyl acetylacetate) chelate, aluminum monoacetylpyruvate bis(2-ethylhexyl acetate) chelate, aluminum acetopyruvate bis(acetylacetate ten Dialkyl ester) chelate, aluminum monoacetylpyruvate bis(oleyl acetate) chelate, etc.

As the titanium chelate compound, for example, diisopropoxy bis(acetylpyruvate) titanium, tetra-n-butyrate titanium, tetra(2-ethylhexanoic acid) titanium, tetraacetylpyruvate titanium, diisopropyl Titanium propoxylate bis (ethyl acetylacetate), titanium octanediol and the like.

Examples of other metal chelate compounds include zirconium tetraacetylpyruvate, zirconium tributoxymonoacetylpyruvate, and the like.

The said metal chelate type crosslinking agent may be used individually by 1 type, and may be used in combination of 2 or more types.

The content of the metal chelate crosslinking agent can be set to any appropriate amount according to the required adhesive force and modulus of elasticity, relative to acrylic polymers with acid functional groups and crystalline resins with a melting point above 25°C The total amount of 100 parts by weight is typically 0.01 parts by weight to 10 parts by weight, more preferably 0.03 parts by weight to 7 parts by weight, and still more preferably 0.05 parts by weight to 5 parts by weight.

＜Substrate＞ As the above-mentioned substrate, a resin film can be preferably used. As the resin constituting the resin film, for example, polyacrylate, polyurethane, polyimide, polyaramide, polyamide, ethylene-vinyl alcohol copolymer, polyetherimide, poly Vinylidene fluoride, polyester, polypropylene, polyethylene, polyphenylene sulfide, etc. These resins may be used alone or in combination of two or more kinds.

The thickness of the aforementioned substrate is preferably 1 μm to 100 μm, more preferably 10 μm to 70 μm, and still more preferably 15 μm to 50 μm.

The haze value of the substrate is preferably 20% or less, more preferably 18% or less, further preferably 10% or less, particularly preferably 8% or less, and most preferably 5% or less. The lower the haze value of the substrate, the better, and the lower limit is, for example, 1%.

When the above-mentioned adhesive tape is stored at an ambient temperature of 5°C for 72 hours, the change rate of the haze value of the base material constituting the adhesive tape ((haze value after 72 hours storage-initial haze value)/initial haze value) is compared It is preferably 20% or less, more preferably 16% or less, still more preferably 10% or less, and particularly preferably 8% or less. The rate of change is as small as possible, and its lower limit is, for example, 2%, preferably 0.1%. [Example]

Hereinafter, the present invention will be described in detail with examples, but the present invention is not limited by these examples. The evaluation methods in the examples are as follows. In addition, in the examples, unless otherwise specified, "parts" and "%" are based on weight.

＜＜Single-sided adhesive tape＞＞ [Example 1] Add 2-ethylhexyl acrylate/acrylic acid (95 parts by weight/5 parts by weight) and 0.2 weight of benzyl peroxide as a starting agent to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser 120 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced into the flask. The liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain an acrylic copolymer with a weight average molecular weight of 1.3 million (1 ). To 75 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L"," weight average molecular weight is added as a modified olefin resin 75,000, melting point 70°C) 25 parts by weight, isocyanate crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L") 2 parts by weight, diluted with toluene to prepare an adhesive with 15% solid content (1) . The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 1).

[Example 2] Except that the addition amount of the isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, brand name "Coronate L") was set to 3 parts by weight, the adhesive (2) was obtained in the same manner as in Example 1. The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 2).

[Example 3] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. With respect to 75 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L"," added as a modified olefin resin, weight Average molecular weight 75,000, melting point 70°C) 25 parts by weight, hydrogenated derivative of C9 petroleum resin (manufactured by Arakawa Chemical Industry Co., Ltd., trade name "Arkon P-125", hydrogenation rate: 95%, softening point: 125°C) 30 2 parts by weight of an isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive (3) with a solid content of 15%. The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 3).

[Example 4] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 75 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-T", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 90°C) 25 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 4). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 12 μm) so that the thickness of the dried adhesive layer became 20 μm to obtain an adhesive tape ( 4).

[Example 5] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. With respect to 85 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., brand name "Toyotac PMA-T", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 90℃) 15 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 5). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 12 μm) so that the thickness of the adhesive layer after drying became 5 μm, to obtain an adhesive tape ( 5).

[Example 6] A polyester film with a thickness of 50 μm (manufactured by TORAY, trade name "Lumirror") was used as a base material, and the thickness of the adhesive layer was set to 20 μm, except that the adhesive tape was produced in the same manner as in Example 4 ( 6).

[Example 7] Add 2-ethylhexyl acrylate/acrylic acid (90 parts by weight/10 parts by weight) and 0.2 weight of benzyl peroxide as a starting agent to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser 120 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced. The liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain an acrylic copolymer with a weight average molecular weight of 1.2 million (2 ). With respect to 85 parts by weight of the acrylic copolymer (2), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., brand name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 70°C) 15 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 6). The resulting adhesive was coated on a substrate (polyimide film, manufactured by TORAY, trade name "Kapton 100H", thickness: 25 μm) so that the thickness of the adhesive layer after drying became 10 μm to obtain Adhesive tape (7).

[Example 8] A polyester film with a thickness of 50 μm (manufactured by TORAY, trade name "Lumirror") was used as a substrate, and the thickness of the adhesive layer was set to 50 μm, except that an adhesive tape was produced in the same manner as in Example 7 ( 8).

[Example 9] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 75 parts by weight of the acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-Lz", weight average molecular weight) is added as a modified olefin resin : 100,000, melting point: 70℃) 25 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 7). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 9).

[Example 10] Add 2-ethylhexyl acrylate/acrylic acid (100 parts by weight/2 parts by weight) and 0.2 weight of benzyl peroxide as a starting agent to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser 230 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced into the flask. The liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain an acrylic copolymer with a weight average molecular weight of 650,000 (3 ). To 70 parts by weight of acrylic copolymer (3), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 70°C) 30 parts by weight, isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L") 2 parts by weight, diluted with toluene to prepare an adhesive with a solid content of 15% ( 8). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 10).

[Example 11] Add n-butyl acrylate/ethyl acrylate/acrylic acid (70 parts by weight / 25 parts by weight / 5 parts by weight) to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser, and peroxide as the initiator 0.2 parts by weight of benzoyl and 120 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced. The liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain acrylic acid with a weight average molecular weight of 700,000. Department of copolymer (4). With respect to 85 parts by weight of acrylic copolymer (4), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., brand name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 70°C) 15 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 9). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 11).

[Example 12] Add n-butyl acrylate/acrylic acid (95 parts by weight/5 parts by weight) and 2,2'-azobisisobutyl as a starting agent to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser 0.2 parts by weight of nitrile and 233 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced. The liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain an acrylic copolymer with a weight average molecular weight of 700,000.物(5). With respect to 85 parts by weight of acrylic copolymer (5), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., brand name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 70°C) 15 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 10). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the dried adhesive layer became 15 μm to obtain an adhesive tape ( 12).

[Example 13] In the same manner as in Example 7, an acrylic copolymer (2) was obtained. To 25 parts by weight of acrylic copolymer (2), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point 70℃) 75 parts by weight, isocyanate crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L") 2 parts by weight, diluted with toluene to prepare an adhesive (11) with a solid content of 15% ). The resulting adhesive was applied to a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 12 μm) so that the thickness of the dried adhesive layer became 3 μm to obtain an adhesive tape ( 13).

[Example 14] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 25 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point 70℃) 75 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content (12 ). The resulting adhesive was coated on a substrate (polyester film, manufactured by TORAY Corporation, trade name "Lumirror", thickness: 50 μm) so that the thickness of the adhesive layer after drying became 25 μm, to obtain an adhesive tape ( 14).

[Example 15] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 15 parts by weight of the acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-T", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point: 90°C) 85 parts by weight, 2 parts by weight of isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L"), diluted with toluene to prepare an adhesive with 15% solid content ( 13). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( 15).

[Example 16] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. With respect to 85 parts by weight of the acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L"," added as a modified olefin resin, weight Average molecular weight 75,000, melting point 70°C) 15 parts by weight, aluminum chelate crosslinking agent (trade name "ALUMI-CHELATE A", manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.5 parts by weight, diluted with toluene to prepare a solid form 15% adhesive (14). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the dried adhesive layer became 20 μm to obtain an adhesive tape ( 16).

[Example 17] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. With respect to 15 parts by weight of the acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L"," added as a modified olefin resin, weight Average molecular weight 75,000, melting point 70°C) 85 parts by weight, aluminum chelate crosslinking agent (trade name "ALUMI-CHELATE A", manufactured by Kawaken Fine Chemicals Co., Ltd.) 0.2 parts by weight, diluted with toluene to prepare a solid form 15% adhesive (15). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 5 μm, to obtain an adhesive tape ( 17).

[Example 18] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. With respect to 25 parts by weight of acrylic copolymer (1), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-T"," added as a modified olefin resin, weight Average molecular weight 75,000, melting point 90°C) 75 parts by weight, epoxy crosslinking agent (manufactured by Mitsubishi Gas Chemical Company, trade name "Tetrad C") 0.1 parts by weight, diluted with toluene to prepare an adhesive with 15% solid content剂(16). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 5 μm, to obtain an adhesive tape ( 18).

[Comparative Example 1] As a modified olefin resin, maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., trade name "Toyotac PMA-L", weight average molecular weight: 75,000, melting point: 70°C) 100 parts by weight Toluene was dissolved to prepare an adhesive (C1) with a solid content of 15%. The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the adhesive layer after drying became 10 μm, to obtain an adhesive tape ( C1).

[Comparative Example 2] Add 2-ethylhexyl acrylate/2-hydroxyethyl acrylate (100 parts by weight/4 parts by weight) to a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen introduction tube, and a condenser, as the starting agent 2. 0.2 parts by weight of 2'-azobisisobutyronitrile and 233 parts by weight of ethyl acetate. While slowly stirring, nitrogen was introduced, and the liquid temperature in the flask was maintained at around 60°C. The polymerization reaction was carried out for about 6 hours to obtain the weight An acrylic copolymer (6) with an average molecular weight of 550,000. With respect to 85 parts by weight of the acrylic copolymer (6), maleic anhydride modified propylene-butene copolymer resin (manufactured by Toyobo Co., Ltd., brand name "Toyotac PMA-L", weight average molecular weight) is added as a modified olefin resin : 75,000, melting point 70°C) 15 parts by weight, isocyanate crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L") 2 parts by weight, diluted with toluene to prepare an adhesive (C2) with 15% solid content ). The resulting adhesive was coated on a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness 30 μm) so that the thickness of the dried adhesive layer became 10 μm to obtain an adhesive tape (C2 ).

[Comparative Example 3] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 75 parts by weight of the acrylic copolymer (1), 25 parts by weight of polyisobutylene resin (manufactured by BASF Corporation, trade name "OPPANOL 12SFN", weight average molecular weight: 51,000) as an olefin resin, and isocyanate-based crosslinking agent ( 2 parts by weight of Tosoh Corporation, brand name "Coronate L"), diluted with toluene to prepare an adhesive (C3) with a solid content of 15%. The resulting adhesive was applied to a substrate (polyester film, manufactured by TORAY, trade name "Lumirror", thickness: 50 μm) so that the thickness of the adhesive layer after drying became 20 μm to obtain an adhesive tape ( C3).

[Comparative Example 4] A polypropylene film with a thickness of 30 μm (manufactured by TORAY, trade name "Torayfan") was used as a substrate, and the thickness of the adhesive layer was set to 10 μm, except that the adhesive tape was produced in the same manner as in Comparative Example 3 ( C4).

＜Evaluation＞ The obtained single-sided adhesive tape was used for the following evaluation. The results are shown in Table 1.

(1) Adhesion (to aluminum plate) The adhesive tapes obtained in the examples and comparative examples were attached to the surface of the aluminum plate under the following conditions to obtain test bodies. Furthermore, the adhesive tapes of Example 13, Example 14, Example 15, Example 17, Example 18, and Comparative Example 1 are thermal adhesive tapes, so they are only crimped by heating (130°C). The other adhesive tapes are crimped at room temperature (25℃) and heated (130℃). Regarding the obtained test body, using a precision universal testing machine (trade name "Autograph AG-I", manufactured by Shimadzu Corporation), the force required to peel the adhesive tape from the surface of the aluminum plate (N/10 mm) was measured under the following conditions , Set as the adhesive force of the adhesive tape. (Crimping conditions) Normal temperature crimping: crimping is carried out with 1 round trip of a 2 kg roller. Heating and crimping: Under the setting that the surface temperature of the laminating device becomes 130°C, the crimp is performed at 0.4 MPa×5 minutes. (Peeling conditions) Temperature: normal temperature (25℃) Peeling speed: 300 mm/min Peel angle: 180°

(2) Adhesion (to polypropylene board) Except for replacing the aluminum plate with a polypropylene plate, the adhesive force of the adhesive tape was measured in the same manner as in the above evaluation (1).

(3) Oil resistance The test body was obtained in the same manner as (1) and (2) above. The obtained test body was immersed in oleic acid at 60°C for 72 hours, and the presence or absence of swelling and peeling of the adhesive tape was visually confirmed. Furthermore, for the test body without peeling of the adhesive tape, after wiping off the oleic acid, it was allowed to stand for 30 minutes in an environment of 23° C. and 50% RH. Thereafter, the adhesive strength of the adhesive tape (adhesive strength after immersion in oleic acid) was measured by the same method as in (1) above. Furthermore, oleic acid is used as a simulated sebum.

(4) Alcohol resistance The test body was obtained in the same manner as (1) and (2) above. The obtained test body was immersed in ethanol at 60°C diluted to 75% by weight with distilled water for 72 hours, and the presence or absence of swelling and peeling of the adhesive tape was visually confirmed. Furthermore, for the test body without peeling of the adhesive tape, after wiping off the oleic acid, it was allowed to stand for 30 minutes in an environment of 23° C. and 50% RH. Thereafter, the adhesive force of the adhesive tape (adhesive force after ethanol immersion) was measured by the same method as in (1) above. In addition, ethanol is used as an alcohol for simulated disinfection.

(5) Fog value Using a haze meter (model: HM-150, manufactured by Murakami Color Research Institute), incident light was irradiated from the side of the adhesive layer to measure the haze value of the adhesive tape. In addition, the adhesive tape was stored in a 5°C environment for 72 hours, and the rate of change in the haze value ((haze value after storage for 72 hours-initial haze value)/initial haze value) was determined.

(6) Retention test The adhesive tapes obtained in the examples and comparative examples were attached to a SUS304BA board under the following conditions to obtain a test body (crimping area: 10 mm×20 mm). Furthermore, the adhesive tapes of Example 13, Example 14, Example 15, Example 17, Example 18, and Comparative Example 1 were thermal adhesive tapes, so they were crimped at a temperature (130°C), except The other adhesive tapes are crimped at room temperature (25°C) and heated (130°C). In addition, with regard to the adhesive tape using a polypropylene film as the base material, a PET adhesive tape (manufactured by Nitto Denko Co., Ltd., trade name "No. 315") was used as a substrate to prepare a test body. (Crimping conditions) Normal temperature crimping: crimping is carried out with 1 round trip of a 2 kg roller. Heating and crimping: Under the setting that the surface temperature of the laminating device becomes 130°C, the crimping is performed at 0.4 MPa×5 minutes. The test body made in the above manner was placed in a vertical direction, and a load of 500 g was applied to the downward direction at an ambient temperature of 130°C, and the retention force was evaluated based on the offset of the adhesive tape after 1 hour. In addition, the offset is described in Table 1.

[Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Example 11 Adhesive composition [parts by weight] Acrylic polymer (1) 2EHA/AA=95/5 (Mw1.3 million) 75 75 75 75 85 85 75 (2) 2EHA/AA=90/10 (Mw1.2 million) 85 85 (3) 2EHA/AA=100/2 (Mw65 million) 70 (4) BA/EA/AA=70/25/5 (Mw700,000) 85 (5) BA/AA=95/5 (Mw700,000) (6) 2EHA/HEA=100/4 (Mw550,000) Olefin resin PMA-L (melting point 70℃) 25 25 25 15 15 30 15 PMA-LZ (melting point 70℃) 25 PMA-T (melting point 90℃) 25 15 15 OPPANOL 12SFN Crosslinking agent Polyisocyanate 2 3 2 2 2 2 2 2 2 2 2 Epoxy Aluminum chelate Adhesion imparting agent Arkon P125 (softening point 125℃) 30 Adhesive layer thickness [μm] 10 10 10 20 5 20 10 50 10 10 10 Substrate PP PP PP PP PP PET PI PET PP PP PP Substrate thickness [μm] 30 30 30 12 12 50 25 50 30 30 30 Evaluation Adhesive tape appearance Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform Adhesion force [N/10 mm] To aluminum plate (crimping at room temperature) 1.00 0.82 1.70 1.30 2.53 3.67 2.73 7.07 1.27 2.07 2.07 To PP board (crimping at room temperature) 0.73 0.65 1.93 0.52 0.88 0.95 1.20 0.90 0.63 1.37 1.12 To aluminum foil (heating and crimping) 3.60 2.81 3.27 5.93 3.07 8.00 3.63 11.3 2.73 2.40 3.13 To PP board (heating and crimping) 5.15 3.40 3.53 5.62 2.33 8.87 2.19 5.70 2.17 4.17 1.95 Oil resistance (oleic acid) [N/10 mm] To aluminum plate (crimping at room temperature) 1.29 0.65 0.20 0.12 0.10 0.15 0.73 1.33 0.10 0.15 0.10 To PP board (crimping at room temperature) 0.35 0.18 0.20 0.13 0.13 0.13 0.68 0.20 0.10 0.10 0.10 To aluminum foil (heating and crimping) 1.80 0.95 0.23 0.55 0.13 1.13 1.10 2.37 0.17 0.20 0.15 To PP board (heating and crimping) 0.60 0.35 0.27 1.43 0.17 1.23 0.80 0.38 0.15 0.13 0.15 Alcohol resistance (ethanol) [N/10 mm] To aluminum plate (crimping at room temperature) 0.32 0.30 0.87 1.23 0.60 0.90 1.83 1.70 0.83 0.63 0.12 To PP board (crimping at room temperature) 1.45 0.90 0.83 0.63 1.03 0.67 1.20 0.85 0.63 1.15 0.15 To aluminum foil (heating and crimping) 0.53 0.46 2.10 3.27 1.30 6.53 2.53 4.63 1.77 0.95 0.20 To PP board (heating and crimping) 1.70 1.51 1.90 3.30 2.13 6.27 2.40 2.89 1.63 1.56 0.25 Haze value [%] Early 4.5 4.8 7.9 6.8 3.4 13.2 7.2 12.3 8.5 9.9 4.9 5℃, 72 hours 4.8 5.1 8.5 7.3 3.6 14.1 7.5 13.5 9.6 11.0 5.5 Haze value change rate 6.7 6.3 7.6 7.4 5.9 6.8 4.2 9.8 12.9 11.1 12.2 Holding force [mm] 0.1 0.1 0.1 0.2 0.1 0.2 0.1 0.1 0.1 0.3 0.2 Example 12 Example 13 Example 14 Example 15 Example 16 Example 17 Example 18 Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Adhesive composition [parts by weight] Acrylic polymer (1) 2EHA/AA=95/5 (Mw1.3 million) 25 15 85 15 25 75 75 (2) 2EHA/AA=90/10 (Mw1.2 million) 25 (3) 2EHA/AA=100/2 (Mw65 million) (4) BA/EA/AA=70/25/5 (Mw700,000) (5) BA/AA=95/5 (Mw700,000) 85 (6) 2EHA/HEA=100/4 (Mw550,000) 85 Olefin resin PMA-L (melting point 70℃) 15 75 75 15 85 100 15 PMA-LZ (melting point 70℃) PMA-T (melting point 90℃) 85 75 OPPANOL 12SFN 25 25 Crosslinking agent Polyisocyanate 2 2 2 2 2 2 2 Epoxy 0.1 Aluminum chelate 0.5 0.2 Adhesion imparting agent Arkon P125 (softening point 125℃) Adhesive layer thickness [μm] 15 3 25 10 20 5 5 10 10 20 10 Substrate PP PP PET PP PP PP PP PP PP PET#50 PP#30 Substrate thickness [μm] 30 12 50 30 30 30 30 30 30 50 30 Evaluation Adhesive tape appearance Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform Uniform mottled mottled Adhesion force [N/10 mm] To aluminum plate (crimping at room temperature) 0.87 1.8 0.13 5.43 2.67 To PP board (crimping at room temperature) 0.30 1.0 0.10 2.93 2.17 To aluminum foil (heating and crimping) 6.45 1.53 10.6 7.1 4.8 2.1 1.9 5.5 0.60 6.30 3.33 To PP board (heating and crimping) 6.47 3.46 19.6 3.4 3.3 2.9 3.2 1.8 0.20 1.40 1.80 Oil resistance (oleic acid) [N/10 mm] To aluminum plate (crimping at room temperature) 0.45 0.1 ×Peel ×Peel ×Peel To PP board (crimping at room temperature) 0.90 0.1 ×Peel ×Peel ×Peel To aluminum foil (heating and crimping) 0.63 1.10 1.9 1.3 0.1 0.7 0.7 4.8 ×Peel ×Peel ×Peel To PP board (heating and crimping) 1.27 1.57 0.8 1.9 0.1 1.4 1.3 1.6 ×Peel ×Peel ×Peel Alcohol resistance (ethanol) [N/10 mm] To aluminum plate (crimping at room temperature) 0.63 3.1 ×Peel 1.03 2.13 To PP board (crimping at room temperature) 0.60 3.1 0.05 0.80 0.87 To aluminum foil (heating and crimping) 0.80 1.00 0.8 2.4 3.1 2.0 1.7 0.9 ×Peel 0.98 1.80 To PP board (heating and crimping) 0.77 1.80 2.0 1.5 3.3 2.2 2.5 1.3 0.05 0.75 0.80 Haze value [%] Early 9.8 2.6 7.3 16.3 2.9 6.1 8.2 6.5 19.4 36.2 24.1 5℃, 72 hours 11.2 2.9 8.0 17.2 3.1 6.5 9.1 7.3 22.1 50.2 33.9 Haze value change rate 14.3 11.5 9.6 5.5 6.9 6.6 11.0 12.3 13.9 38.7 40.7 Holding force [mm] 0.2 0.2 0.3 0.8 0.1 1.2 0.7 Drop 0.1 0.7 0.4

＜＜Double-sided adhesive tape＞＞ [Example 19] The adhesive (1) was obtained in the same manner as in Example 1. The resulting adhesive was applied to the release film (polysiloxane-treated release film, manufactured by TORAY, trade name "Cerapeel", thickness: 38 μm) so that the thickness of the dried adhesive layer became 10 μm. )on. The adhesive layer with release film obtained in the above manner was attached to both sides of a substrate (polyester film, manufactured by TORAY, trade name "Lumirror", thickness 38 μm) to obtain a double-sided adhesive tape (19 ).

[Example 20] An adhesive (12) was obtained in the same manner as in Example 14. The resulting adhesive (12) was applied to a substrate (polyimide film, manufactured by TORAY-DUPONT, trade name "Kapton 100H", thickness 25 μm) so that the thickness of the dried adhesive layer became 5 μm ) One side. Then, in the same manner as in Example 1, an adhesive (1) was obtained. The resulting adhesive (1) was applied to a release film (polysiloxane-treated release film, manufactured by TORAY company, trade name "Cerapeel", thickness of the adhesive layer after drying became 10 μm). : 38 μm). The adhesive layer with the release film obtained in the above manner is attached to the other side of the substrate to obtain a double-sided adhesive tape (20).

[Example 21] An adhesive (15) was prepared in the same manner as in Example 17. The resulting adhesive (15) was applied to one side of a substrate (polypropylene film, manufactured by TORAY Corporation, trade name "Torayfan", thickness: 30 μm) so that the thickness of the dried adhesive layer became 5 μm. Then, in the same manner as in Example 1, an adhesive preparation liquid (1) was obtained. The obtained adhesive compounding solution (1) is applied to the release film (polysiloxane-treated release film, manufactured by TORAY, trade name "Cerapeel") so that the thickness of the dried adhesive layer becomes 10 μm , Thickness: 38 μm). The adhesive layer with the release film obtained in the above manner is attached to the other side of the substrate to obtain a double-sided adhesive tape (21).

[Comparative Example 5] In the same manner as in Example 1, an acrylic copolymer (1) was obtained. To 100 parts by weight of the acrylic copolymer (1), 2 parts by weight of an isocyanate-based crosslinking agent (manufactured by Tosoh Corporation, trade name "Coronate L") was added and diluted with toluene to prepare an adhesive with 15% solid content (C5). The resulting adhesive was applied to the release film (polysiloxane-treated release film, manufactured by TORAY, trade name "Cerapeel", thickness: 38 μm) so that the thickness of the dried adhesive layer became 10 μm. )on. The adhesive layer with release film obtained in the above manner was attached to both sides of a substrate (polyester film, manufactured by TORAY, trade name "Lumirror", thickness 38 μm) to obtain a double-sided adhesive tape (C5 ).

＜Evaluation＞ The obtained double-sided adhesive tape was used for the above-mentioned (5) and the following evaluation. The results are shown in Table 2.

(7) Evaluation of oil resistance A polypropylene plate was placed on one side of the double-sided adhesive tape, and an aluminum plate was placed on the other side. The surface temperature of the laminating device was set to 130°C and crimped at 0.4 MPa×5 minutes to make a test piece. Furthermore, regarding the double-sided adhesive tapes of Examples 20 and 21, a polypropylene plate was arranged on the side of the adhesive layer formed by the adhesives (12) and (15). The obtained test body was immersed in oleic acid at 60°C for 72 hours, and the presence or absence of swelling and peeling of the adhesive tape was visually confirmed.

(8) Evaluation of alcohol resistance A test piece was produced in the same manner as in the above evaluation (7). The obtained test body was immersed in ethanol at 60°C diluted to 75% by weight with distilled water for 72 hours, and the presence or absence of swelling and peeling of the adhesive tape was visually confirmed.

[Table 2] Example 19 Example 20 Example 21 Comparative example 5 Adhesive layer 1 Adhesive layer 2 Adhesive layer 1 Adhesive layer 2 Adhesive layer 1 Adhesive layer 2 Adhesive layer 1 Adhesive layer 2 Acrylic copolymer (1) 2EHA/AA=95/5 (Mw1.3 million) 75 75 25 75 15 75 100 100 Olefin resin PMA-L (melting point 70℃) 25 25 75 25 85 25 Crosslinking agent Polyisocyanate 2 2 2 2 2 2 2 Aluminum chelate 0.2 Substrate PET 38 μm PI 25 μm PP 30 μm PET 38 μm Adhesive layer thickness [μm] 10 10 5 10 5 10 10 10 Oil resistance (oleic acid) No bumps, peeling No bumps, peeling No bumps, peeling Peel off Alcohol resistance (ethanol) No bumps, peeling No bumps, peeling No bumps, peeling Peel off Haze value [%] Early 5.8 6.4 6.8 2.1 5℃×72 hours later 6.5 7.3 7.4 2.3 Change rate of fog value [%] 12.1 14.1 8.8 9.5

10: Substrate 20: Adhesive layer 100: Adhesive tape

Fig. 1 is a schematic cross-sectional view of an adhesive tape according to an embodiment of the present invention.

10: Substrate

20: Adhesive layer

100: Adhesive tape

Claims (10)

An adhesive tape, which is provided with a substrate and an adhesive layer disposed on at least one side of the substrate, and The adhesive layer contains an adhesive that exhibits adhesiveness by crimping, The adhesive includes an acrylic polymer with an acid functional group and a crystalline resin with a melting point of 25°C or higher, The haze value of the adhesive tape is less than 20%. Such as the adhesive tape of claim 1, which exhibits adhesiveness by heating. The adhesive tape of claim 1 or 2, wherein the acrylic polymer having an acid functional group contains an alkyl (meth)acrylate derived from a linear or branched alkyl group having a carbon number of 4 or more Structural unit a. The adhesive tape of claim 3, wherein the content ratio of the structural unit a is 50 parts by weight or more relative to 100 parts by weight of the acrylic polymer having an acid functional group. The adhesive tape according to any one of claims 1 to 4, wherein the crystalline resin is a polyolefin resin. The adhesive tape of claim 5, wherein the polyolefin resin is a maleic anhydride modified polyolefin resin, a maleic acid modified polyolefin resin or an acrylic acid modified polyolefin resin. The adhesive tape according to any one of claims 1 to 6, wherein the adhesive comprises C5 series petroleum resin and/or C9 series petroleum resin. The adhesive tape according to any one of claims 1 to 7, wherein the base material is selected from polyacrylate, polyurethane, polyimide, polyaramide, polyamide, ethylene-vinyl alcohol At least one of copolymer, polyetherimide, polyvinylidene fluoride, polyester, polypropylene, polyethylene, and polyphenylene sulfide is formed. The adhesive tape of any one of claims 1 to 8, wherein a release film is provided on the side of the adhesive layer opposite to the base material. The adhesive tape of any one of claims 1 to 9, which is provided with the adhesive layer on both sides of the substrate.

Images