KR102413880B1 - Silicon-based adhesive tape - Google Patents

Abstract

점착력 A: 유리에 부착하고, 85℃에서 48시간 보존한 후의 유리에 대한 점착력
점착력 B: 실리콘계 박리제를 함유하지 않는 실리콘계 점착제층을 기재 필름의 한쪽 면측에 갖는 점착 테이프를 유리에 부착하고, 85℃에서 48시간 보존한 후의 유리에 대한 점착력Provided is a silicone-based adhesive tape that is light-peelable to an adherend, suppresses an increase in adhesive strength over time, can maintain adhesive strength of light-peelability over time, and can achieve light peelability even after storage over time.
The silicone-based adhesive tape of the present invention has a silicone-based adhesive layer containing a silicone-based polymer and a silicone-based release agent on at least one side of a base film,
The initial adhesive strength is 0.01 to 0.10N/25mm,
It is characterized in that the value of Equation 1 below is 80 or less.
<Equation 1>

Adhesion A: Adhesion to glass after being attached to glass and stored at 85°C for 48 hours
Adhesive force B: Adhesive force to glass after an adhesive tape having a silicone pressure-sensitive adhesive layer containing no silicone release agent on one side of the base film is attached to glass, and stored at 85° C. for 48 hours

Description

Silicone-based adhesive tape {SILICON-BASED ADHESIVE TAPE}

The present invention relates to a silicone adhesive tape.

BACKGROUND ART Silicone-based adhesive tapes are used in various fields because they are excellent in adhesiveness, heat resistance, chemical resistance, weather resistance, and the like. For example, a silicone-based adhesive tape having a silicone-based adhesive layer on one side of the synthetic resin film substrate (see Patent Document 1), organopolysiloxane, organopolysiloxane having a hydrosilyl group, and a silicone-based adhesive composition containing a platinum-based catalyst A silicone-based adhesive tape (refer to Patent Document 2) having a formed silicone-based pressure-sensitive adhesive layer is used. However, the said silicone adhesive tape had the problem that the adhesive force with respect to a to-be-adhered body rises with time.

Japanese Patent Laid-Open No. Hei 10-338852 Japanese Patent Laid-Open No. 2002-180025

Further, in the silicone pressure-sensitive adhesive tape, it is required that the adhesive force to the adherend be light-peelable even after storage with time, that is, the force generated by the contact between the adhesive surface and the adherend is small.

Therefore, an object of the present invention is light peeling from an adherend, and the increase in adhesive force over time is suppressed, and the adhesive force of light peeling can be maintained over time, and also, light peeling can be achieved even after storage with time. To provide an adhesive tape.

Therefore, as a result of intensive studies by the present inventors, in a silicone pressure-sensitive adhesive tape having a silicone pressure-sensitive adhesive layer, the silicone pressure-sensitive adhesive layer contains a silicone-based release agent, and if the adhesive strength is adjusted within a predetermined range, constant adhesiveness can be maintained over time Moreover, even after storage with time, it discovered that the adhesive force with respect to a to-be-adhered body can be made light peeling, and completed this invention.

That is, the present invention has a silicone-based pressure-sensitive adhesive layer containing a silicone-based polymer and a silicone-based release agent on at least one side of the base film,

The initial adhesive strength is 0.01 to 0.10N/25mm,

It provides a silicone-based adhesive tape, characterized in that the value of Equation 1 is 80 or less.

Adhesion A: Adhesion to glass after being attached to glass and stored at 85° C. for 48 hours

Adhesive force B: Adhesive force to glass after an adhesive tape having a silicone pressure-sensitive adhesive layer containing no silicone release agent on one side of the base film is attached to glass, and stored at 85° C. for 48 hours

It is preferable that content of the silicone release agent in the said silicone adhesive layer is 0.2 weight part or more and 100 weight part or less with respect to 100 weight part of silicone type polymers.

It is preferable that the haze of the said silicone adhesive layer is 1.5 % or less.

It is preferable that the said base film is a polyester film.

Since the silicone-based adhesive tape of the present invention has the above configuration, it is light-peelable to an adherend, and an increase in adhesive strength over time is suppressed, and it is possible to maintain the light-peelable adhesive force over time, and also light-peelable even after storage with time. can be achieved For this reason, even after a long period of time has elapsed since adhesion to an adherend, the adherend can be easily peeled from the adherend without damaging it, and the adhesive force to the adherend can be reduced even after storage with time.

[Silicone-based adhesive tape]

The silicone pressure-sensitive adhesive tape of the present invention has at least a silicone pressure-sensitive adhesive layer (silicone pressure-sensitive adhesive layer) containing a silicone-based polymer as a base polymer and a silicone-based release agent. In addition, in this specification, said "silicone-type adhesive layer containing a silicone-type polymer and a silicone type release agent" may be called "silicone-type adhesive layer A."

In addition, in this specification, the meaning of "adhesive sheet" shall also be included in "adhesive tape". In addition, in this specification, the composition used when forming the said silicone adhesive layer A may be called "silicone type adhesive composition A." An adhesive composition is a composition used for formation of an adhesive layer, and shall include the meaning of the composition used for formation of an adhesive.

The silicone adhesive tape of this invention has a silicone adhesive layer A on the at least one surface side of a base film. That is, the silicone adhesive tape of this invention is an adhesive tape provided with a base material. In addition, the silicone adhesive tape of this invention may be a single-sided adhesive type adhesive tape which has an adhesive surface only on one side, and the double-sided adhesive type adhesive tape which has an adhesive surface on both surfaces may be sufficient as it. In addition, when the silicone adhesive tape of this invention is a double-sided adhesive tape, the silicone adhesive tape of this invention may have the form in which both adhesive surfaces are provided by the silicone adhesive layer A, and one adhesive surface is a silicone adhesive layer. It is provided by A, and you may have the aspect provided in which the other adhesive surface is provided by other adhesive layers (adhesive layers other than the silicone adhesive layer A).

In addition to the base film and the silicone pressure-sensitive adhesive layer A, the silicone pressure-sensitive adhesive tape of the present invention may have an pressure-sensitive adhesive layer (other pressure-sensitive adhesive layer) other than the pressure-sensitive adhesive layer A, and other layers (eg, an intermediate layer, an undercoat layer, etc.). In addition, the surface (adhesive surface) of the adhesive layer of the silicone type adhesive tape of this invention may be protected by the release liner.

(Silicone-based pressure-sensitive adhesive layer A)

The silicone adhesive tape of this invention has the silicone adhesive layer A at least. The silicone pressure-sensitive adhesive layer A contains at least a silicone-based polymer as a base polymer and a silicone-based release agent. In the silicone pressure-sensitive adhesive tape of the present invention, the pressure-sensitive adhesive surface provided by the silicone pressure-sensitive adhesive layer A is a light-peelable surface, and an increase in the adhesive force over time is suppressed, and constant adhesion can be maintained. It is estimated that this is because the silicone type release agent contained in the silicone type adhesive layer A exists uniformly on the silicone type adhesive layer A surface, and it is hardening|curing.

The silicone-based pressure-sensitive adhesive layer A contains a silicone-based polymer as a base polymer. Although content of the silicone polymer in silicone adhesive layer A is not specifically limited, It is preferable to contain 50 weight% or more with respect to silicone adhesive layer A whole quantity (100 weight%), More preferably, it is 60 weight% or more.

The said silicone adhesive layer A is formed of the silicone adhesive composition A. The silicone pressure-sensitive adhesive layer A is not particularly limited, and for example, a silicone pressure-sensitive adhesive layer formed of a peroxide crosslinking type silicone pressure sensitive adhesive composition (peroxide curable silicone pressure sensitive adhesive composition) or an addition reaction type silicone pressure sensitive adhesive composition is preferably mentioned, and addition reaction More preferably, the silicone pressure-sensitive adhesive layer A formed from the silicone pressure-sensitive adhesive composition is mentioned.

Moreover, as silicone adhesive composition A, a phenyl group containing silicone adhesive composition is preferable. As said phenyl group containing silicone adhesive composition, polyalkylphenyl silicone adhesive compositions, such as a polymethylphenyl silicone adhesive composition and a polyethylphenyl silicone adhesive composition, etc. are mentioned, for example.

As said addition-reaction silicone adhesive composition, the addition-reaction type silicone adhesive composition (addition reaction type phenyl group containing silicone adhesive composition) by organopolysiloxane which has a phenyl group is preferable. Examples of the organopolysiloxane having a phenyl group in such an addition reaction type phenyl group-containing silicone pressure-sensitive adhesive composition include polyalkylphenyls such as polymethylphenylsiloxane (polymethylphenylsilicone) and polyethylphenylsiloxane (polyethylphenylsilicone). Siloxane (polyalkylphenyl silicone) etc. are mentioned.

It is preferable that the said addition reaction type silicone adhesive composition contains a silicone rubber and a silicone resin.

The silicone rubber is not particularly limited as long as it is a silicone rubber component, and a silicone rubber containing an organopolysiloxane having a phenyl group (particularly, an organopolysiloxane having methylphenyl siloxane as a main structural unit) is preferable. Various functional groups, such as a vinyl group, may be introduce|transduced into the organopolysiloxane in such a silicone rubber as needed. Moreover, the weight average molecular weight of the said organopolysiloxane is although it does not specifically limit, It is preferable that it is 150,000 or more, More preferably, it is 280,000-1 million, More preferably, it is 500,000-900,000.

The silicone resin is not particularly limited as long as it is a silicone-based resin used in a silicone pressure-sensitive adhesive (silicone-based pressure-sensitive adhesive). For example, M units including _the structural unit “R ₃ -Si _1/2 ” _, the structural unit “SiO ₂ ” having at least one unit selected from a Q unit, a T unit containing a structural unit “R-SiO _{3 / 2} ”, and a D unit containing a structural unit “R ₂ -SiO” (empty) Silicone resin containing organopolysiloxane containing a polymer, etc. are mentioned. In addition, R in the said structural unit represents a hydrocarbon group or a hydroxyl group. Examples of the hydrocarbon group include an aliphatic hydrocarbon group (such as an alkyl group such as a methyl group and an ethyl group), an alicyclic hydrocarbon group (such as a cycloalkyl group such as a cyclohexyl group), and an aromatic hydrocarbon group (such as an aryl group such as a phenyl group and a naphthyl group) and the like. As a ratio (ratio) of the said "M unit" and "at least one type of unit selected from a Q unit, a T unit, and a D unit", for example, the former/the latter (molar ratio) = 0.3/1 to 1.5/1 (preferably It is preferably 0.5/1 to 1.3/1).

Various functional groups, such as a vinyl group, may be introduce|transduced into the organopolysiloxane in the said silicone resin as needed. In addition, the functional group to be introduced may be a functional group capable of generating a crosslinking reaction. It is preferable that the weight average molecular weight of the organopolysiloxane in a silicone resin is 1000 or more, More preferably, it is 1000-20000, More preferably, it is 1500-10000.

Although it does not specifically limit as a compounding ratio of the said silicone rubber and the said silicone resin, It is preferable to set it as 100-220 weight part (especially 120-180 weight part) of silicone resin with respect to 100 weight part of silicone rubbers.

In addition, in the silicone pressure-sensitive adhesive composition containing the silicone rubber and the silicone resin, the silicone rubber and the silicone resin may be in a mixed state in which they are merely mixed, and by the mixing, the silicone rubber and the silicone resin react to form a condensate ( In particular, it may be in the condensed state used as partial condensate).

Further, the silicone pressure-sensitive adhesive A contains a silicone-based release agent. Although it does not specifically limit as said silicone type release agent, For example, a thermosetting silicone type release agent, an ionizing radiation-curable silicone type release agent, etc. are mentioned. In addition, any of the solvent type melt|dissolved or disperse|distributed to the solvent-free type which does not contain a solvent and the organic solvent may be sufficient as a silicone type release agent. In addition, a silicone type release agent can be used individually or in combination of 2 or more types.

Although it does not specifically limit as said thermosetting silicone type release agent, It is preferable that organohydrogenpolysiloxane and the organopolysiloxane which has an aliphatic unsaturated group are included. Moreover, it is preferable that the said silicone type release agent is a heat addition reaction curable silicone type release agent which crosslinking by thermal addition reaction occurs and hardens|cures.

Although it does not specifically limit as said heat addition reaction curable silicone type release agent, Polysiloxane (Si-H group containing polysiloxane) which has a hydrogen atom (H) bonded to a silicon atom (Si) in a molecule|numerator, Si-H bond in a molecule|numerator (Si and A release agent containing polysiloxane (Si-H group reactive polysiloxane) containing a functional group (Si-H group reactive functional group) having reactivity with respect to a covalent bond of H) is preferably used. In addition, this release agent hardens|cures by bridge|crosslinking with Si-H group and Si-H group reactive functional group addition reaction.

In the Si-H group-containing polysiloxane, the Si to which H is bonded may be either Si in the main chain or Si in the side chain. As for the said Si-H group containing polysiloxane, the polysiloxane which contains two or more Si-H groups in a molecule|numerator is preferable. As polysiloxane containing two or more Si-H groups, dimethylhydrogensiloxane polymers, such as poly(dimethylsiloxane-methylsiloxane), are mentioned preferably.

In addition, as the Si-H group-reactive polysiloxane, a Si-H group-reactive functional group or a side chain containing such a functional group forms the main chain (framework) of the siloxane-based polymer (for example, Si at the end of the main chain, the inside of the main chain) of Si) bonded to polysiloxane is preferably used. Among them, polysiloxane in which a Si-H group reactive functional group is directly bonded to Si in the main chain is preferable. Furthermore, as said Si-H group-reactive polysiloxane, the polysiloxane which contains two or more Si-H group-reactive functional groups in a molecule|numerator is also mentioned preferably.

Examples of the Si-H group-reactive functional group in the Si-H group-reactive polysiloxane include an alkenyl group such as a vinyl group and a hexenyl group. In addition, as the siloxane-based polymer forming the main chain portion in the Si-H group reactive polysiloxane, for example, polydialkylsiloxane such as polydimethylsiloxane, polydiethylsiloxane, and polymethylethylsiloxane (two alkyl groups are the same or may be different); polyalkylarylsiloxanes; Poly(dimethylsiloxanemethylsiloxane), the polymer formed by superposing|polymerizing several Si containing monomers, etc. are mentioned. Especially, as a siloxane type polymer which forms a main chain part, polydimethylsiloxane is preferable.

In particular, the heat addition reaction curable silicone release agent is a heat addition reaction curable silicone release agent containing a polysiloxane containing two or more Si-H groups in a molecule and a polysiloxane containing two or more Si-H group reactive functional groups in a molecule. it is preferable

Moreover, although it does not specifically limit as said ionizing radiation-curable silicone type release agent, A UV-curable silicone type release agent which a crosslinking reaction occurs and hardens|cures by ultraviolet (UV) irradiation is mentioned preferably.

The UV-curable silicone-based release agent is a release agent that is cured by causing chemical reactions such as cationic polymerization, radical polymerization, radical addition polymerization, and hydrosilylation reaction by UV irradiation. The UV-curable silicone-based release agent is particularly preferably a UV-curable silicone-based release agent that is cured by cationic polymerization.

Although it does not specifically limit as a cationic polymerization type UV-curable silicone type release agent, At least two epoxy groups are Si (for example, Si at the end of a main chain, Si inside a main chain) which forms the main chain (skeleton) of a siloxane-type polymer, and / Or Si included in the side chain, each directly or through a divalent group (alkylene group such as methylene group and ethylene group; Preferably, it is mentioned. The bonding form to Si of these at least two epoxy groups may be the same or different. That is, the release agent containing the polysiloxane containing 2 or more types of 1 type, or 2 or more types of epoxy group containing side chain is mentioned preferably. Examples of the epoxy group-containing side chain include a glycidyl group, a glycidoxy group (glycidyloxy group), a 3,4-epoxycyclohexyl group, and a 2,3-epoxycyclopentyl group. The epoxy group-containing polysiloxane may be linear, branched, or a mixture thereof.

In particular, in the silicone pressure-sensitive adhesive tape of the present invention, it is preferable to include a thermosetting silicone-based release agent in the silicone-based pressure-sensitive adhesive A from the viewpoint of obtaining an excellent level of suppression of an increase in adhesive strength over time, and it is preferable to include a heat-addition reaction curable silicone-based release agent more preferably.

Although content of the said silicone release agent in the silicone adhesive layer A of the silicone adhesive tape of this invention is not specifically limited, It is preferable that it is 0.2 weight part or more and 100 weight part or less with respect to 100 weight part of silicone polymers which are a base polymer, More preferable Preferably it is 0.2 weight part or more and 80 weight part or less, More preferably, it is 0.2 weight part or more and less than 60 weight part. When the said content is 0.2 weight part or more, it will become easy to acquire the effect of suppressing the increase of the adhesive force in time by making a silicone type release agent contain a silicone type adhesive layer. Moreover, when the said content is 100 weight part or less, it will become easy to suppress the problem that sufficient adhesiveness is not acquired but adhesion to a to-be-adhered body becomes difficult.

Furthermore, the additive may be contained in the silicone adhesive layer A of the silicone adhesive tape of this invention as needed. That is, the said silicone adhesive composition A may contain the additive other than a silicone type release agent as needed. Moreover, the said silicone adhesive composition A may contain the catalyst (particularly, a platinum catalyst etc.). Although it does not specifically limit as said additive, A crosslinking agent, a filler, a plasticizer, an anti-aging agent, an antistatic agent, a coloring agent (pigment, dye, etc.) etc. are mentioned. In addition, an additive can be used individually or in combination of 2 or more types.

The silicone pressure-sensitive adhesive composition containing the silicone rubber and the silicone resin may contain a crosslinking agent from the viewpoint of obtaining a silicone pressure sensitive adhesive layer that is a crosslinked structure. Although it does not specifically limit as such a crosslinking agent, A siloxane type crosslinking agent (silicone type crosslinking agent), a peroxide type crosslinking agent, etc. are mentioned preferably. In addition, a crosslinking agent can be used individually or in combination of 2 or more types.

Although it does not specifically limit as said siloxane type crosslinking agent, Polyorganohydrogensiloxane which has two or more hydrogen atoms couple|bonded with the silicon atom in the molecule|numerator is mentioned preferably. In such a polyorganohydrogensiloxane, various organic groups other than a hydrogen atom may couple|bond with the silicon atom with which the hydrogen atom has couple|bonded. Examples of the organic group include an alkyl group such as a methyl group and an ethyl group; Aryl groups, such as a phenyl group; A halogenated alkyl group etc. are mentioned. Especially, from a viewpoint of a synthesis|combination and handling, an alkyl group is preferable and a methyl group is more preferable. In addition, although the skeleton structure of polyorganohydrogensiloxane may have any skeleton structure of linear, branched, and cyclic|annular form, linear form is suitable.

As described above, the silicone pressure-sensitive adhesive layer A of the present invention is formed of the silicone pressure-sensitive adhesive composition A. The silicone pressure-sensitive adhesive composition A is a composition used for formation of the silicone pressure-sensitive adhesive layer A, and contains at least the silicone polymer as the base polymer and the silicone release agent. Although the silicone adhesive layer A is not specifically limited, For example, it can obtain by mixing the said silicone type polymer, the said silicone type release agent, etc.

The viscosity of the silicone pressure-sensitive adhesive composition A is not particularly limited, but is preferably 0.1 to 100 Pa·s, more preferably 0.5 to 50 Pa·s from the viewpoint of workability, handleability, and easiness of forming a uniform pressure-sensitive adhesive layer. In addition, in this specification, using a BH viscometer as a viscometer, a viscosity shall mean the viscosity measured on the conditions of a rotor: No. 5 rotor, rotation speed: 10 rpm, and measurement temperature: 30 degreeC.

The silicone pressure-sensitive adhesive layer A is formed by obtaining a layered silicone pressure-sensitive adhesive composition A and curing the layered product. For example, it forms by obtaining an adhesive composition layer from the silicone adhesive composition A, and heating and drying the adhesive composition layer (for example, heat-processing at the temperature of 100-160 degreeC for 1-10 minutes).

Although the thickness of the silicone pressure sensitive adhesive layer A is not specifically limited, From the point of adhesive reliability, 3-200 micrometers is preferable, More preferably, it is 5-150 micrometers, More preferably, it is 5-100 micrometers.

Although the haze (according to JIS K7136) of the silicone adhesive layer A is not specifically limited, From a point of obtaining high transparency, 1.5 % or less is preferable, More preferably, it is 1.0 % or less. In addition, the haze bonds the silicone adhesive layer A to slide glass (for example, the thing of 91.8% of total light transmittance, haze 0.4%), for example, The haze meter (made by Murakami Shikisai Kijutsu Corporation) , trade name "HM-150") can be used for measurement.

In addition, the transmittance|permeability (total light transmittance in a visible light wavelength region, according to JISK7361-1) of the silicone adhesive layer A is although it does not specifically limit, From a point of obtaining high transparency, 80% or more is preferable, More preferably, 85 % or more. In addition, the transmittance|permeability is, for example by bonding the silicone adhesive layer A to slide glass (for example, the thing of 91.8% of total light transmittance, haze 0.4%), and a haze meter (manufactured by Murakami Shikisai Kijutsu Genmyeonsho Co., Ltd.) , trade name "HM-150") can be used for measurement.

(base film)

As mentioned above, the silicone adhesive tape of this invention is an adhesive tape provided with the base material which has a base film and the silicone adhesive layer A at least. Moreover, the base film which consists of one layer may be sufficient as a base film, and may have a laminated structure of two or more layers.

It is preferable that the said base film is a plastic base material (polymer base material). Although it does not specifically limit as a material which comprises the said plastic base material (polymer base material), For example, Polyester, such as a polyethylene terephthalate, a polyethylene naphthalate, a polybutylene terephthalate, and a polybutylene naphthalate; polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer; polyvinyl alcohol; polyvinylidene chloride; polyvinyl chloride; vinyl chloride-vinyl acetate copolymer; polyvinyl acetate; polyamide; polyimide; celluloses such as triacetyl cellulose and diacetyl cellulose; fluorine-based resin; polyether; polyetheramides; polyether ether ketone; polyphenylene sulfide; polystyrene-based resins such as polystyrene; polycarbonate; polyether sulfone; Acrylic resins, such as polymethyl methacrylate, etc. are mentioned. In addition, the said material can be used individually or in combination of 2 or more types.

Among them, as a material constituting the plastic substrate, polyester, cellulose, acrylic resin, etc. are preferable and more preferable from the viewpoint of good balance of strength, handleability (handling property), cost, dimensional stability, and anchoring force. It is preferably polyester. That is, it is preferable that the said plastic base material is a polyester film, a cellulose film, and an acrylic resin film, More preferably, it is a polyester film.

The said base film may be surface-treated as needed. For example, the deformability may be controlled by the extending|stretching process (uniaxial stretching or biaxial stretching) etc. of the said base film. In addition, on the surface of the base film, in order to increase adhesion with the pressure-sensitive adhesive layer, conventional surface treatment, for example, chromic acid treatment, ozone exposure, flame exposure, high-pressure electric shock exposure, oxidation by chemical or physical methods such as ionizing radiation treatment processing or the like may be performed.

Furthermore, the primer process for raising the adhesive force with an adhesive layer may be given. In particular, the base film, in order to increase the adhesion with the silicone pressure-sensitive adhesive layer A, it is preferable that the silicone primer treatment.

In addition, the said base film may be hard-coat-processed at the point which improves surface abrasion resistance (abrasive-resistance). When such a hard-coat process is given and it uses as an object for surface protection, the protective function can be improved more. Moreover, the antistatic treatment may be given to a base film at the point which suppresses generation|occurrence|production of static electricity.

The said base material may be a base material to which the primer process was given in order to improve adhesiveness with an adhesive layer on one surface, for example, and the hard-coat process was given to the other surface.

(Releasable Liner)

As described above, the silicone pressure-sensitive adhesive tape of the present invention may be provided with a release liner in order to protect the pressure-sensitive adhesive surface. The said release liner is not specifically limited, A well-known thru|or a common release liner can be used. For example, as said release liner, Polyester-type resin, such as a polyethylene terephthalate (PET), a polyethylene naphthalate (PEN), and a polybutylene terephthalate (PBT); olefin resins containing α-olefins such as polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer (EVA) as a monomer component; polyvinyl chloride (PVC); vinyl acetate-based resin; polycarbonate (PC); polyphenylene sulfide (PPS); amide resins such as polyamide (nylon) and wholly aromatic polyamide (aramid); polyimide-based resin; polyetheretherketone (PEEK); olefin resins such as polyethylene (PE) and polypropylene (PP); Fluorine resins such as polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoroethylene-vinylidene fluoride copolymer, etc. A plastic film comprised is mentioned preferably.

Further, as the release liner, for example, a release liner having a release layer (release treatment layer) on at least one surface of the release liner substrate, a release liner containing a fluorine-based polymer, a release liner containing a fluorine-based polymer, a release liner containing a non-polar polymer, a low-adhesive property containing a non-polar polymer A release liner etc. are mentioned. Moreover, the release liner base material which does not have a release layer (ie, the release liner base material itself) is also mentioned. Although it does not specifically limit as said fluorine-type polymer, For example, polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoro An ethylene-vinylidene fluoride copolymer etc. are mentioned. Moreover, although it does not specifically limit as said nonpolar polymer, For example, olefin resins, such as polyethylene (PE) and polypropylene (PP), etc. are mentioned. Among them, it is preferable to use a release liner having a release layer on at least one surface of the release liner substrate and a release liner substrate not having a release layer (that is, the release liner substrate itself).

Although it does not specifically limit as said release liner base material, A plastic film etc. are mentioned. As such a plastic film, For example, Polyester-type resin, such as a polyethylene terephthalate (PET), a polyethylene naphthalate (PEN), and a polybutylene terephthalate (PBT); olefin resins containing α-olefins such as polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, and ethylene-vinyl acetate copolymer (EVA) as a monomer component; polyvinyl chloride (PVC); vinyl acetate-based resin; polycarbonate (PC); polyphenylene sulfide (PPS); amide resins such as polyamide (nylon) and wholly aromatic polyamide (aramid); polyimide-based resin; and a plastic film composed of polyether ether ketone (PEEK) or the like. Among them, from the viewpoints of workability, availability, workability, dustproofness, cost, and the like, a plastic film formed of a polyester-based resin is preferable, and a PET film is more preferable.

Although it does not specifically limit as a peeling agent which comprises the said peeling layer, For example, peeling agents, such as a silicone type peeling agent, a fluorine-type peeling agent, a long-chain alkyl type peeling agent, and molybdenum sulfide, are mentioned. In addition, a peeling treatment agent can be used individually or in combination of 2 or more type.

The said release liner can be manufactured by a well-known and usual method. In addition, the thickness of the said release liner is not specifically limited.

(Silicone-based adhesive tape)

Although the manufacturing method of the silicone type adhesive tape of this invention is not specifically limited, A well-known formation method can be used. For example, it can produce by forming the silicone adhesive layer A from the said silicone adhesive composition A in the at least one surface side of the said base film.

The initial adhesive force of the silicone-based adhesive tape of the present invention (in particular, the initial adhesive force of the adhesive surface provided by the silicone-based adhesive layer A) is 0.01 to 0.10 N/25 mm, preferably 0.01 to 0.08 N/25 mm, more preferably 0.01 to 0.05N/25mm. Since the silicone adhesive tape of this invention has an initial stage adhesive force of 0.01 N/25 mm or more, sufficient adhesiveness can be acquired with respect to a to-be-adhered body. Further, since the initial adhesive force is 0.10 N/25 mm or less, it is easily peelable to the adherend, and the adhesive force to the adherend is small. For this reason, even if it adheres to a to-be-adhered body, it can peel easily from a to-be-adhered body, without damaging a to-be-adhered body. In addition, initial adhesive force is the meaning of the adhesive force at the time of sticking and pasting up the adhesive tape which is not pasted or stored to a to-be-adhered body. Initial adhesive force is calculated|required by measuring the adhesive force at the time of peeling 30 minutes after bonding an adhesive tape to a to-be-adhered body. The initial adhesive force is measured under peeling conditions of a tensile rate: 300 mm/min and a peeling angle: 180°, and is the adhesive force to the glass plate. In addition, it measures in the atmosphere of measurement temperature:23 degreeC, and relative humidity:50%RH. Moreover, as a glass plate, a glass plate (Soda-lime glass #0050, the Matsunami Glass Kogyo Co., Ltd. make) is mentioned, for example.

In the silicone adhesive tape of this invention, it is preferable that the value of following formula (1) is 80 or less.

<Equation 1>

Adhesion A: Adhesion to glass after being attached to glass and stored at 85° C. for 48 hours

Adhesive force B: Adhesive force to glass after an adhesive tape having a silicone pressure-sensitive adhesive layer containing no silicone release agent on the surface of the base film is attached to glass, and stored at 85° C. for 48 hours

The adhesive force A and the adhesive force B are measured under peeling conditions of a tensile rate: 300 mm/min, and a peeling angle: 180 degrees, and are adhesive force with respect to a glass plate. In addition, it measures in the atmosphere of measurement temperature:23 degreeC, and relative humidity:50%RH.

As a glass plate, a glass plate (Soda-lime glass #0050, the Matsunami Glass Kogyo Co., Ltd. make) is mentioned, for example.

The pressure-sensitive adhesive tape used in the measurement of the adhesive force A is an adhesive tape having a silicone pressure-sensitive adhesive layer containing a silicone-based release agent on at least one side of the base film, and the pressure-sensitive adhesive tape used in the measurement of the adhesive force B is a silicone-based release agent that does not contain a silicone-based release agent. It is an adhesive tape which has an adhesive layer on the at least one surface side of a base film. When the adhesive tape used by the measurement of the adhesive force A and the adhesive tape used by the measurement of the adhesive force B are contrasted, it is the same except for the presence or absence of containing the silicone type release agent in a silicone pressure sensitive adhesive layer. For example, the adhesive tape used by the measurement of the adhesive force A and the adhesive tape used by the measurement of the adhesive force B WHEREIN: The thickness of a silicone adhesive layer is the same, and the material and thickness of a base film are the same.

In addition, storage for 48 hours at 85 degreeC corresponds to long-term storage at normal temperature.

The silicone adhesive tape of this invention WHEREIN: The value of Formula (1) is 80 or less, Preferably it is 75 or less. Since the silicone-based adhesive tape of the present invention has a value of 80 or less in formula (1), an increase in adhesive force over time is suppressed, and a constant adhesive force can be maintained, and a constant adhesive force can be maintained even if stored with time.

Moreover, it is preferable that the silicone type adhesive tape of this invention is transparent.

Although the haze (according to JISK7136) of the silicone adhesive tape of this invention is not specifically limited, From a point of obtaining high transparency, 1.5 % or less is preferable, More preferably, it is 1.0 % or less. In addition, the haze is, for example, by bonding the silicone adhesive tape of the present invention to a slide glass (for example, a thing having a total light transmittance of 91.8% and a haze of 0.4%), and a haze meter (Kijutsu Murakami Shikisai Corporation). It can be measured using the product made by Genmyosho, trade name "HM-150").

In addition, the transmittance|permeability (total light transmittance in a visible light wavelength region, according to JIS K7361-1) of the silicone adhesive tape of this invention is although it does not specifically limit, From the point of obtaining high transparency, 80% or more is preferable, More preferably is 85% or more. The transmittance is, for example, by bonding the silicone adhesive tape of the present invention to a slide glass (for example, having a total light transmittance of 91.8% and a haze of 0.4%), and using a haze meter (Kijutsu Murakami Shikisai Corporation). It can be measured using the product made by Genmyosho, trade name "HM-150").

Although the thickness of the silicone adhesive tape of this invention is not specifically limited, 15-400 micrometers is preferable, More preferably, it is 20-300 micrometers, More preferably, it is 25-250 micrometers.

Since the silicone adhesive tape of this invention has a silicone adhesive layer A, while exhibiting sufficient adhesiveness with respect to a to-be-adhered body, the adhesive force increasing property in time-lapse|temporality is suppressed. Moreover, it is light peeling with respect to a to-be-adhered body, and it is light peeling with respect to a to-be-adhered body even after long-term storage. For this reason, the silicone adhesive tape of this invention can maintain fixed adhesive force for a long period of time. Accordingly, the silicone-based adhesive tape of the present invention can be easily peeled from the adherend without damaging the adherend even after a long period of time has elapsed after being adhered to the adherend. That is, the silicone adhesive tape of this invention is excellent in re-peelability.

For example, even if the silicone-based adhesive tape of the present invention is adhered to a fragile adherend such as a thin semiconductor wafer, and a long time elapses, the silicone-based adhesive tape of the present invention can be easily removed from the adherend without damaging the adherend. can be peeled off.

Since the silicone adhesive tape of this invention has said characteristic, it is used suitably as a surface protection film. For example, it is preferably used for surface protection uses, such as a thin-layer display member, a thin-layer display device, a thin-layer optical film, and an electronic device. Although it does not specifically limit as said thin-layer display device, A touch panel using LCD etc. is mentioned preferably. Although it does not specifically limit as said thin-layer display member, LCD, a color filter used for it, etc. are mentioned preferably. Although it does not specifically limit as said thin-layer optical film, A polarizing plate is mentioned preferably.

[Example]

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. The present invention is not limited by these at all.

(Example 1)

Silicone adhesive 1 (addition reaction type silicone adhesive, trade name “X-40-3306”, manufactured by Shin-Etsu Chemical Co., Ltd.): 100 parts by weight, platinum-based catalyst 1 (trade name “CAT-PL-50T”, Shin-Etsu Chemical Co., Ltd.) Etsu Chemical Co., Ltd.): 0.4 parts by weight, silicone-based release agent 1 (addition-reactive silicone-based release agent containing dimethylpolysiloxane as a main component, trade name “KS-776A”, manufactured by Shin-Etsu Chemical Co., Ltd.) : By mixing 0.5 parts by weight, a silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 1) was prepared.

Silicone-based pressure-sensitive adhesive composition 1 was applied to the silicone-primed side of the base film 1 (polyester film with silicone primer on one side, thickness 38 μm, trade name “Diafoil MRF#38”, manufactured by Mitsubishi Jushi Co., Ltd.), A film having a silicone pressure-sensitive adhesive composition layer was obtained.

Next, the film having the above silicone pressure-sensitive adhesive composition layer is heated under the conditions of temperature: 30 ° C., time: 2 minutes, and further subjected to a heat drying treatment of heating under the conditions of temperature: 130 ° C. and time: 3 minutes, A silicone-based pressure-sensitive adhesive layer having a thickness of 75 μm was formed. And the silicone type adhesive tape which has a silicone type adhesive layer on the single side|surface side of a base film was obtained.

In addition, on the adhesive surface of the silicone adhesive tape, a polyethylene terephthalate film (a polyethylene terephthalate film not subjected to a peeling treatment) was bonded to protect the silicone adhesive layer.

(Example 2)

A silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 2) was prepared in the same manner as in Example 1, except that the amount of the silicone-based release agent 1 (the number of additions) was set to 1.0 parts by weight.

Except having used this silicone adhesive composition 2, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 3)

A silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 3) was prepared in the same manner as in Example 1, except that the amount (the number of additions) of the silicone-based release agent 1 was 3.0 parts by weight.

Except having used this silicone adhesive composition 3, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 4)

A silicone pressure-sensitive adhesive composition (silicone pressure-sensitive adhesive composition 4) was prepared in the same manner as in Example 1, except that the amount (number of additions) of the silicone release agent 1 was 5.0 parts by weight.

Except having used this silicone adhesive composition 4, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 5)

A silicone pressure-sensitive adhesive composition (silicone pressure-sensitive adhesive composition 5) was prepared in the same manner as in Example 1, except that the amount of the silicone release agent 1 (the number of additions) was 10.0 parts by weight.

Except having used this silicone adhesive composition 5, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 6)

A silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 6) was prepared in the same manner as in Example 1, except that the amount (the number of additions) of the silicone-based release agent 1 was 30.0 parts by weight.

Except having used this silicone adhesive composition 6, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 7)

A silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 7) was prepared in the same manner as in Example 1, except that the amount (the number of additions) of the silicone-based release agent 1 was 50.0 parts by weight.

Except having used this silicone adhesive composition 4, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 8)

Using the silicone adhesive composition 2, except having made the thickness of the adhesive composition 2 after drying into 10 micrometers, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Example 9)

Except having used the silicone adhesive composition 3, it carried out similarly to Example 8, and obtained the silicone adhesive tape.

(Comparative Example 1)

A silicone-based pressure-sensitive adhesive composition (silicone-based pressure-sensitive adhesive composition 8) was prepared in the same manner as in Example 1 except that the silicone-based release agent 1 was not added.

Except having used this silicone adhesive composition 8, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Comparative Example 2)

A silicone pressure-sensitive adhesive composition (silicone pressure-sensitive adhesive composition 9) was prepared in the same manner as in Example 1, except that the amount of the silicone release agent 1 (the number of additions) was 0.1 parts by weight.

Except having used this silicone adhesive composition 9, it carried out similarly to Example 1, and obtained the silicone adhesive tape.

(Comparative Example 3)

Except having used the silicone adhesive composition 8, it carried out similarly to Example 8, and manufactured the silicone adhesive tape.

(Comparative Example 4)

Except having used the silicone adhesive composition 9, it carried out similarly to Example 8, and manufactured the silicone adhesive tape.

[measurement]

About the silicone adhesive tape obtained by the Example and the comparative example, the initial adhesive force, the adhesive force A, and the adhesive force B were calculated|required using the following measuring method of adhesive force. Moreover, the value of Formula 1 [(Adhesive force A)/(Adhesive force B) x 100] was calculated|required from this adhesive force A and adhesive force B.

Further, a silicone pressure-sensitive adhesive layer was bonded to a slide glass (total light transmittance 91.8%, haze 0.4%) to obtain a measurement sample, and from this measurement sample, a haze meter (manufactured by Murakami Shikisai Kijutsu Corporation, trade name “HM”) -150") was used to determine the haze of the silicone pressure-sensitive adhesive layer and the total light transmittance of the silicone pressure-sensitive adhesive layer.

(Measurement of adhesive force)

After leaving the silicone adhesive tape to stand for 30 minutes in 23 degreeC and 50%RH atmosphere, the sheet piece of 100 mm in length and 25 mm in width was obtained from the silicone adhesive tape. Then, in 23 degreeC, 50%RH atmosphere, the release liner is peeled from the said sheet piece, the adhesive surface (measurement surface) is exposed, and the sheet piece is a glass plate (soda-lime glass #0050, Matsunami Glass Kogyo Co., Ltd.) The sheet piece was bonded to the glass plate by crimping|compressing-bonding on the conditions of a 2 kg roller and 1 reciprocation to Shiki Corporation). And using a tensile tester (trade name "TCM-1kNB", manufactured by Minebea), a 180° peel test was performed, and 180° peel adhesive force (180° peel adhesive force) (N/25 mm) was measured. The measurement was performed under the conditions of a peeling angle of 180 degrees and a tensile rate of 300 mm/min in 23 degreeC and 50%RH atmosphere.

(Initial Adhesion)

After producing a silicone adhesive tape, adhesive force was calculated|required with respect to the silicone adhesive tape by the said measuring method of adhesive force. This adhesive force was made into initial stage adhesive force.

In addition, as a measurement of initial stage adhesive force, after bonding a sheet piece to a glass plate and leaving it to stand for 30 minutes, the 180 degree peeling test was done.

(Adhesive force A)

After producing the silicone adhesive tape, it was left to stand under the temperature of 85 degreeC for 48 hours, and it was set as the silicone adhesive tape after heating and leaving it to stand. Adhesive force was calculated|required by the said measuring method of the said adhesive force about this silicone type adhesive tape after leaving-to-heat. This adhesive force was called adhesive force A.

(Adhesive force B)

For the Examples and Comparative Examples regarding the silicone pressure-sensitive adhesive tape containing the silicone-based release agent in the silicone-based pressure-sensitive adhesive layer, in the same procedure except that the silicone-based release agent was added, the silicone pressure-sensitive adhesive tape corresponding to each Example and Comparative Example was referred to. produced.

This silicone-based adhesive tape as a reference does not contain a silicone-based release agent in the silicone-based pressure-sensitive adhesive layer, and is the same as the silicone-based adhesive tape of the corresponding Example or Comparative Example except for the presence or absence of the silicone-based release agent.

After producing this silicone adhesive tape as a reference, it was left to stand under the temperature of 85 degreeC for 48 hours, and it was set as the reference silicone adhesive tape after heating and leaving. The adhesive force was calculated|required by the measuring method of the said adhesive force about the silicone type adhesive tape of the reference after this heating and leaving-to-stand. This adhesive force was called adhesive force B.

In addition, about the comparative example which does not contain a silicone type release agent, the value of adhesive force A was employ|adopted as a value of adhesive force B for convenience.

Claims (4)

Having a silicone pressure-sensitive adhesive layer formed of a silicone pressure-sensitive adhesive composition containing a silicone pressure-sensitive adhesive and an addition-reactive silicone-based release agent on at least one side of the base film,
The initial adhesive strength is 0.01 to 0.10N/25mm,
A silicone-based adhesive tape, characterized in that the value of the following formula (1) is 80 or less.
<Equation 1>

Adhesion A: Adhesion to glass after being attached to glass and stored at 85°C for 48 hours
Adhesive force B: Adhesive force to glass after an adhesive tape having a silicone pressure-sensitive adhesive layer containing no silicone release agent on one side of the base film is attached to glass, and stored at 85° C. for 48 hours The silicone pressure-sensitive adhesive tape according to claim 1, wherein a content of the silicone release agent in the silicone pressure-sensitive adhesive layer is 0.2 parts by weight or more and 100 parts by weight or less with respect to 100 parts by weight of the silicone-based polymer. The silicone adhesive tape of Claim 1 or 2 whose haze of the said silicone adhesive layer is 1.5 % or less. The silicone-based adhesive tape according to claim 1 or 2, wherein the base film is a polyester film.