TWI729972B - Silicon-based adhesive tape - Google Patents

Abstract

The present invention provides a silicone adhesive tape, which is lightly peelable relative to the adherend, the increase of the adhesive force over time is suppressed, and the light peeling adhesive force can be maintained over time. In addition, after being stored over time Light peeling can also be achieved.

The silicone adhesive tape of the present invention is characterized in that at least one side of the base film has a silicone adhesive layer containing a silicone adhesive and a silicone release agent, and the initial adhesive force is 0.01~0.10N/25mm, the value of the following formula (1) is 80 or less.

(Adhesion A)/(Adhesion B)×100 (1)

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

Adhesive force B: Attach an adhesive tape with a silicone adhesive layer that does not contain a silicone release agent on one side of the substrate film on the glass, and store it at 85°C for 48 hours. Adhesion

Description

Silicone adhesive tape

The invention relates to a silicone adhesive tape.

The silicone adhesive tape has excellent adhesion, heat resistance, chemical resistance, weather resistance, etc., so it can be used in various fields. For example, the following silicone adhesive tape can be used: a silicone adhesive tape with a silicone adhesive layer on one side of a synthetic resin film substrate (refer to Patent Document 1); The silicone adhesive tape of the silicone adhesive layer formed by the agent composition, the silicone adhesive composition contains organopolysiloxane, organopolysiloxane with hydrosilyl group, platinum series Catalyst (refer to Patent Document 2). However, the above-mentioned silicone adhesive tape has a problem that the adhesive force to the adherend increases over time.

[Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 10-338852

[Patent Document 2] Japanese Patent Laid-Open No. 2002-180025

In addition, the silicone adhesive tape is required to have a light peeling force to the adherend even after being stored over time, that is, the force generated by the contact between the adhesive surface and the adherend is relatively small.

Therefore, the purpose of the present invention is to provide a silicone adhesive tape, which is relatively The adhesive body is lightly peeled, the increase of the adhesive force over time is suppressed, and the light peeling adhesive force can be maintained over time. In addition, light peeling can also be achieved after being stored over time.

Therefore, the inventors conducted diligent studies and found that in a silicone adhesive tape with a silicone adhesive layer, if the silicone adhesive layer contains a silicone release agent, the When the adhesive force is adjusted to a specific range, the fixed adhesiveness can be maintained over time, and even after time-lapse storage, the adhesive force to the adherend can be lightly peeled, thereby completing the present invention.

That is, the present invention provides a silicone adhesive tape characterized by having a silicone adhesive layer containing a silicone adhesive and a silicone release agent on at least one side of a base film, and The initial adhesive force is 0.01~0.10N/25mm, and the value of the following formula (1) is 80 or less, (adhesive force A)/(adhesive force B)×100 (1)

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

Adhesive force B: Attach an adhesive tape with a silicone adhesive layer that does not contain a silicone release agent on one side of the substrate film on the glass, and store it at 85°C for 48 hours. Adhesion.

The content of the silicone release agent in the silicone adhesive layer is preferably 0.2 parts by weight or more and 100 parts by weight relative to 100 parts by weight of the silicone adhesive.

The haze of the silicone adhesive layer is preferably 1.5% or less.

The above-mentioned base film is preferably a polyester film.

The silicone adhesive tape of the present invention has the above-mentioned structure, so it is relatively For light peeling, the increase of the adhesive force over time is suppressed, and the light peeling adhesive force can be maintained over time. In addition, light peeling can be achieved after being stored over time. Therefore, even if a long period of time has elapsed since being attached to the adherend, it can be easily peeled off from the adherend without damaging the adherend. Moreover, even after being stored over time, the adherend can be The adhesive force is small.

[Polysiloxane adhesive tape]

The silicone adhesive tape of the present invention has at least a silicone adhesive layer (polysilicon pressure sensitive adhesive layer) containing a silicone adhesive and a silicone release agent. Furthermore, in this specification, there are cases where the above-mentioned "polysiloxane-based adhesive layer containing a polysiloxane-based adhesive and a polysiloxane-based release agent" is referred to as "polysiloxane-based adhesive layer A".

In addition, in this manual, the meaning of "adhesive sheet" is also included in "adhesive tape". In addition, in this specification, the composition used when forming the polysiloxane-based adhesive layer A may be referred to as "polysiloxane-based adhesive composition A". The adhesive composition is a composition used for the formation of an adhesive layer, and includes the meaning of a composition used for the formation of an adhesive.

The silicone adhesive tape of the present invention has a silicone adhesive layer A on at least one side of the base film. That is, the silicone adhesive tape of the present invention is an adhesive tape attached to a substrate. In addition, the silicone adhesive tape of the present invention may be a single-sided adhesive tape having an adhesive surface on only one side, or a double-sided adhesive tape having adhesive surfaces on both sides. Furthermore, when the silicone adhesive tape of the present invention is a double-sided adhesive tape, the silicone adhesive tape of the present invention may have a form in which both adhesive surfaces are provided by the silicone adhesive layer A. It may have a form in which one adhesive surface is provided by the silicone adhesive layer A, and the other adhesive surface is provided by other adhesive layers (adhesive layers other than the silicone adhesive layer A).

The silicone adhesive tape of the present invention can also be used in addition to the base film and silicone adhesive layer A. In addition, there are adhesive layers (other adhesive layers) and other layers (for example, intermediate layer, primer layer, etc.) other than the adhesive layer A. In addition, the surface of the adhesive layer (adhesive surface) of the silicone adhesive tape of the present invention can also be protected by a release liner.

(Polysiloxane adhesive layer A)

The silicone adhesive tape of the present invention has at least a silicone adhesive layer A. The silicone adhesive layer A contains at least a silicone adhesive and a silicone release agent. In the silicone adhesive tape of the present invention, the adhesive surface provided by the silicone adhesive layer A is a lightly peelable surface, the increase in adhesive force over time is suppressed, and the fixed adhesiveness can be maintained. It is presumed that the reason is that the silicone release agent contained in the silicone adhesive layer A uniformly exists on the surface of the silicone adhesive layer A and hardens.

The silicone adhesive layer A contains a silicone adhesive. The content of the silicone adhesive in the silicone adhesive layer A is not particularly limited, and it is preferably 50% by weight or more relative to the total amount (100% by weight) of the silicone adhesive layer A, and more Preferably, it is 60% by weight or more.

The silicone adhesive layer A is formed of the silicone adhesive composition A. The silicone adhesive layer A is not particularly limited. For example, a peroxide-crosslinked silicone adhesive composition (peroxide-curable silicone adhesive composition ) Or the polysiloxane adhesive layer formed by the addition reaction type polysiloxane adhesive composition, more preferably the polysiloxane formed by the addition reaction type polysiloxane adhesive composition系 Adhesive layer A.

In addition, as the silicone adhesive composition A, a silicone adhesive composition containing a phenyl group is preferred. As the above-mentioned phenyl-containing silicone adhesive composition, for example, polyalkylbenzenes such as polymethylphenyl silicone adhesive composition, polyethylphenyl silicone adhesive composition, etc. Base silicone adhesive composition, etc.

As the above-mentioned addition reaction type silicone adhesive composition, an addition reaction type silicone adhesive composition using an organopolysiloxane having a phenyl group (addition reaction type containing phenyl group The silicone adhesive composition). As this kind of addition reaction type containing benzene The organopolysiloxanes with phenyl groups in the silicone-based adhesive composition, for example, polymethylphenylsiloxane (polymethylphenylpolysiloxane), or polyethylphenyl Silicone (polyethylphenyl polysiloxane) and other polyalkylphenylsiloxanes (polyalkylphenyl polysiloxane) and the like.

The above-mentioned addition reaction type silicone adhesive composition preferably contains silicone rubber and silicone resin.

The silicone rubber mentioned above is not particularly limited as long as it is a silicone rubber component. It preferably contains an organopolysiloxane having a phenyl group (especially a methylphenylsiloxane as the main structure). Unit of organopolysiloxane) silicone rubber. For the organopolysiloxane in this silicone rubber, various functional groups such as vinyl groups can also be introduced as needed. Furthermore, the weight average molecular weight of the aforementioned organopolysiloxane is not particularly limited, and is preferably 150,000 or more, more preferably 280,000 to 1 million, and still more preferably 500,000 to 900,000.

In addition, the silicone resin is not particularly limited as long as it is a silicone-based resin used in a silicone-based adhesive (polysiloxane-based pressure-sensitive adhesive). For example, it may include ( Co) polymer such as organopolysiloxane, polysiloxane resin, etc. The (co)polymer has an _{M unit containing the structural unit "R 3} -Si _1/2 ", and is selected from the group containing the structural unit "SiO ₂ " At least one of the Q unit, _{the T unit including the structural unit "R-SiO 3/2} ", and the D unit including the structural unit "R _{2 -SiO".} Furthermore, R in the above structural unit represents a hydrocarbon group or a hydroxyl group. Examples of the above-mentioned hydrocarbon group include aliphatic hydrocarbon groups (alkyl groups such as methyl and ethyl groups, etc.), alicyclic hydrocarbon groups (cycloalkyl groups such as cyclohexyl, etc.), and aromatic hydrocarbon groups (aryl groups such as phenyl and naphthyl groups, etc.) Wait. As the ratio (ratio) of the above-mentioned "M unit" and "at least one unit selected from Q unit, T unit and D unit", for example, the former/the latter (molar ratio)=0.3/1~1.5/ 1 (preferably 0.5/1 to 1.3/1).

For the organopolysiloxane in the aforementioned polysiloxane resin, various functional groups such as vinyl groups can also be introduced as needed. Furthermore, the introduced functional group may also be a functional group that can undergo a crosslinking reaction. The weight average molecular weight of the organopolysiloxane in the polysiloxane resin is preferably 1,000 or more, more preferably 1,000 to 20,000, and still more preferably 1,500 to 10,000.

The blending ratio of the silicone rubber and the silicone resin is not particularly limited. It is preferable that the silicone resin is set to 100 to 220 parts by weight (especially 120 to 100 parts by weight) relative to 100 parts by weight of the silicone rubber. 180 parts by weight).

Furthermore, in the silicone adhesive composition containing silicone rubber and silicone resin, the silicone rubber and silicone resin can be in a purely mixed state, or through the mixing, The silicone rubber reacts with the silicone resin to become a condensate (especially a partial condensate) in a condensed state.

In addition, the silicone-based adhesive A contains a silicone-based release agent. The silicone-based release agent is not particularly limited, and examples thereof include thermosetting silicone-based release agents, ionizing radiation-curable silicone-based release agents, and the like. In addition, the silicone-based release agent may be a solvent-free type that does not contain a solvent, and a solvent type that is dissolved or dispersed in an organic solvent. In addition, the silicone release agent can be used individually or in combination of 2 or more types.

The thermosetting silicone-based release agent is not particularly limited, but it is preferably one containing organohydrogenpolysiloxane and organopolysiloxane having an aliphatic unsaturated group. In addition, the above-mentioned silicone release agent is preferably a thermal addition reaction curable silicone release agent that undergoes crosslinking and hardening by a thermal addition reaction.

The thermal addition reaction-curable silicone-based release agent is not particularly limited, and preferably includes the following release agent: a polymer containing a hydrogen atom (H) bonded to a silicon atom (Si) in the molecule Siloxanes (polysiloxanes containing Si-H groups) and functional groups that are reactive to Si-H bonds (the covalent bond between Si and H) (Si-H reactive functional groups) in the molecule The polysiloxane (Si-H-based reactive polysiloxane). Furthermore, the release agent is hardened by the addition reaction of the Si-H group and the Si-H group reactive functional group and crosslinking.

In the above-mentioned polysiloxane containing Si-H groups, the Si to which H is bonded may be either Si in the main chain or Si in the side chain. The above-mentioned polysiloxane containing Si-H groups is preferably a polysiloxane containing two or more Si-H groups in the molecule. As the polysiloxane containing more than two Si-H groups, preferably dimethyl hydrogen silicon such as poly(dimethylsiloxane-methylsiloxane) Oxyane-based polymers.

In addition, as the above-mentioned Si-H-based reactive polysiloxanes, the following polysiloxanes can be preferably cited: Si-H-based reactive functional groups or side chains containing the functional groups are bonded to form silicon The Si of the main chain (skeleton) of the oxane-based polymer (for example, Si at the end of the main chain, Si inside the main chain). Among them, polysiloxanes in which Si-H-based reactive functional groups are directly bonded to Si in the main chain are preferred. Furthermore, as the aforementioned Si-H-based reactive polysiloxane, a polysiloxane containing two or more Si-H-based reactive functional groups in the molecule can also be preferably cited.

Examples of the Si-H group reactive functional group in the above Si-H group reactive polysiloxane include alkenyl groups such as a vinyl group and a hexenyl group. In addition, examples of the silicone polymer forming the main chain part of the above-mentioned Si-H-based reactive polysiloxane include polydimethylsiloxane, polydiethylsiloxane, and polymethylsiloxane. Polydialkylsiloxanes such as ethylsiloxane (2 alkyl groups can be the same or different); polyalkylarylsiloxanes; poly(dimethylsiloxane-methylsiloxane) , Polymers formed by the polymerization of multiple monomers containing Si, etc. Among them, as the silicone polymer forming the main chain part, polydimethylsiloxane is preferred.

In particular, the thermal addition reaction curable polysiloxane-based release agent preferably contains a polysiloxane containing two or more Si-H groups in the molecule and a reactive functional group containing two or more Si-H groups in the molecule. The thermal addition reaction of polysiloxane is a curable polysiloxane-based release agent.

In addition, the ionizing radiation-curable silicone-based release agent is not particularly limited, and preferably includes a UV-curable silicone-based release agent that undergoes a cross-linking reaction by irradiation with ultraviolet rays (UV) and is cured.

The above-mentioned UV curable silicone release agent is a release agent that is cured by chemical reactions such as cationic polymerization, free radical polymerization, free radical addition polymerization, and hydrosilation reaction when irradiated with UV. The above-mentioned UV-curable silicone-based release agent is particularly preferably a UV-curable silicone-based release agent that is cured by cationic polymerization.

The cationic polymerization type UV curable silicone-based release agent is not particularly limited, but preferably includes the following epoxy-containing silicone release agents, which contain epoxy groups At least two epoxy groups of the polysiloxane are directly or via divalent groups (alkylene groups such as methylene and ethylene groups; alkoxy groups such as ethoxy groups and propoxy groups, etc.) It is formed by bonding Si (for example, Si at the end of the main chain, Si inside the main chain) and/or Si contained in the side chain that forms the main chain (skeleton) of the siloxane-based polymer. The bonding state of the at least two epoxy groups to Si may be the same or different. That is, preferably, a release agent containing one or more types of polysiloxane containing two or more epoxy-containing side chains can be cited. As a side chain containing an epoxy group, a glycidyl group, a glycidyloxy group (glycidyloxy group), a 3,4-epoxycyclohexyl group, a 2,3-epoxycyclopentyl group, etc. are mentioned. The epoxy-containing polysiloxane may be linear, branched, or a mixture thereof.

In particular, in terms of achieving an excellent level of suppression of the increase in adhesive force over time, the silicone adhesive tape of the present invention preferably contains thermosetting silicone in the silicone adhesive A It is a release agent, and more preferably includes a heat-addition reaction curable silicone release agent.

The content of the silicone release agent in the silicone adhesive layer A of the silicone adhesive tape of the present invention is not particularly limited, and it is preferably relative to 100 parts by weight of the silicone adhesive 0.2 parts by weight or more and 100 parts by weight or less, more preferably 0.2 parts by weight or more and 80 parts by weight or less, and still more preferably 0.2 parts by weight or more and less than 60 parts by weight. If the above content is 0.2 parts by weight or more, it becomes easy to obtain the effect of suppressing the increase in adhesive force over time by including the silicone release agent in the silicone adhesive layer. Moreover, if the said content is 100 weight part or less, it becomes easy to suppress the inconvenience that sufficient adhesiveness is not obtained, and it becomes difficult to stick to a to-be-adhered body.

Furthermore, in the silicone adhesive layer A of the silicone adhesive tape of the present invention, additives may be included as needed. That is, the above-mentioned silicone adhesive composition A may contain additives as necessary in addition to the silicone release agent. In addition, the above-mentioned silicone adhesive composition A may contain a catalyst (especially a platinum-based catalyst, etc.). The above-mentioned additives are not particularly limited, and examples include crosslinking agents, fillers, plasticizers, anti-aging agents, antistatic agents, and Colorants (pigments or dyes, etc.), etc. In addition, additives can be used individually or in combination of 2 or more types.

From the aspect of obtaining the silicone adhesive layer as a crosslinked structure, the silicone adhesive composition containing silicone rubber and silicone resin may also contain a crosslinking agent. It does not specifically limit as such a crosslinking agent, Preferably, a silicone type crosslinking agent (polysiloxane type crosslinking agent), a peroxide type crosslinking agent, etc. are mentioned. In addition, a crosslinking agent can be used individually or in combination of 2 or more types.

The siloxane-based crosslinking agent is not particularly limited, and preferably includes polyorganohydrogensiloxanes having two or more hydrogen atoms bonded to silicon atoms in the molecule. In this type of polyorganohydrogensiloxane, various organic groups can be bonded to the silicon atom to which the hydrogen atom is bonded, in addition to the hydrogen atom. Examples of the organic group include alkyl groups such as methyl and ethyl; aryl groups such as phenyl; halogenated alkyl groups and the like. Among them, from the viewpoint of synthesis or handling, an alkyl group is preferred, and a methyl group is more preferred. In addition, the skeleton structure of the polyorganohydrosiloxane may have any one of linear, branched, and cyclic, and is preferably linear.

As described above, the silicone adhesive layer A of the present invention is formed from the silicone adhesive composition A. The silicone adhesive composition A is a composition used for the formation of the silicone adhesive layer A, and contains at least the silicone adhesive and the silicone release agent. The silicone adhesive layer A is not particularly limited. For example, it can be obtained by mixing the silicone adhesive, the silicone release agent, and the like.

The viscosity of the silicone adhesive composition A is not particularly limited. From the aspects of workability, handling, and ease of formation of a uniform adhesive layer, it is preferably 0.1-100 Pa‧s, more preferably 0.5 ~50Pa‧s. Furthermore, in this specification, the so-called viscosity refers to the viscosity measured under the conditions of a No. 5 rotator, a number of revolutions: 10 rpm, and a measurement temperature of 30°C using a BH viscometer as a viscometer.

The silicone adhesive layer A is formed by obtaining a layered silicone adhesive composition A and hardening the layer. For example, it is formed by the following method: self-polysilicone adhesive The adhesive composition A obtains an adhesive composition layer, and the adhesive composition layer is heated and dried (for example, heat treatment is performed at a temperature of 100 to 160° C. for 1 to 10 minutes).

The thickness of the silicone adhesive layer A is not particularly limited. From the aspect of bonding reliability, it is preferably 3 to 200 μm, more preferably 5 to 150 μm, and even more preferably 5 to 100 μm.

The haze (according to JIS K7136) of the silicone adhesive layer A is not particularly limited, but in terms of obtaining higher transparency, it is preferably 1.5% or less, more preferably 1.0% or less. Furthermore, for the haze, for example, the silicone adhesive layer A can be attached to the glass slide (for example, the total light transmittance is 91.8%, and the haze is 0.4%), using a haze meter (Murakami Color Technology Research Manufactured by Co., Ltd., trade name "HM-150").

In addition, the transmittance of the silicone adhesive layer A (total light transmittance in the visible light wavelength region, according to JIS K7361-1) is not particularly limited, but from the viewpoint of obtaining higher transparency, it is preferably 80 % Or more, more preferably 85% or more. Furthermore, the transmittance can be, for example, the silicone adhesive layer A is attached to the glass slide (for example, the total light transmittance is 91.8%, the haze is 0.4%), using a haze meter (Murakami Color Technology Research Manufactured by Co., Ltd., trade name "HM-150").

(Base film)

As described above, the silicone adhesive tape of the present invention is an adhesive tape with a substrate having at least a base film and a silicone adhesive layer A. Furthermore, the base film may be a base film including one layer, or may have a laminated structure of two or more layers.

The aforementioned substrate film is preferably a plastic substrate (polymer substrate). The material constituting the above-mentioned plastic substrate (polymer substrate) is not particularly limited, and examples include polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, and polybutylene terephthalate. Polyesters such as butylene naphthalate; polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymers; polyvinyl alcohol; polyvinylidene chloride; polyvinyl chloride; vinyl chloride-vinyl acetate copolymer; polyacetic acid Vinyl esters; polyamides; polyimines; celluloses such as triacetyl cellulose and diacetyl cellulose; fluorine-based resins; polyethers; polyether amides; polyether ether ketones; polyphenylene sulfide; Polystyrene such as polystyrene Series resins; polycarbonate; polyether block; acrylic resins such as polymethyl methacrylate, etc. In addition, these materials can be used individually or in combination of 2 or more types.

Among them, as the material constituting the above-mentioned plastic substrate, in terms of a good balance of strength, handling (handling), cost, dimensional stability, and gripping power, polyester, cellulose, or acrylic are preferred. The resin, etc., is more preferably polyester. That is, the above-mentioned plastic substrate is preferably a polyester film, a cellulose film, or an acrylic resin film, and more preferably a polyester film.

The above-mentioned base film may also be subjected to surface treatment as needed. For example, the above-mentioned base film may be deformed by stretching treatment (uniaxial stretching or biaxial stretching) or the like. In addition, in order to improve the adhesion with the adhesive layer, the surface of the substrate film can also be subjected to conventional surface treatments, such as chromic acid treatment, ozone exposure, flame exposure, high-voltage electric shock exposure, ionized radiation treatment, etc. using chemical or physical Method of oxidation treatment, etc.

Furthermore, it is also possible to perform primer treatment to improve the adhesion with the adhesive layer. In particular, in order to improve the adhesion with the silicone adhesive layer A, the above-mentioned base film is preferably one that has undergone a silicone primer treatment.

In addition, in terms of improving the scratch resistance (abrasion resistance) of the surface, the above-mentioned base film may be subjected to a hard coating treatment. If such a hard coating treatment is carried out, its protective function can be further improved when it is used for surface protection. In addition, in terms of self-suppression of the generation of static electricity, the base film may be subjected to antistatic treatment.

The above-mentioned substrate may be, for example, a substrate in which one surface is subjected to a primer treatment to improve the adhesion with the adhesive layer, and the other surface is subjected to a hard coating treatment.

(Release liner)

As mentioned above, the silicone adhesive tape of the present invention can also be provided with a release liner to protect the adhesive surface. The said release liner is not specifically limited, A well-known or commonly used release liner can be used. For example, as the above-mentioned release liner, a plastic film containing the following can preferably be cited: polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PEN) Polyester (PBT) and other polyester resins; polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), Ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA) and other olefin resins with α-olefin as the monomer component; polyvinyl chloride (PVC); vinyl acetate resin; polycarbonate (PC); Polyphenylene sulfide (PPS); polyamide (nylon), fully aromatic polyamide (aromatic polyamide) and other amide resins; polyimide resin; polyether ether ketone (PEEK); poly Olefin resins such as ethylene (PE) and polypropylene (PP); polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, chlorofluoroethylene- Fluorine resins such as vinylidene fluoride copolymers, etc.

In addition, as the above-mentioned release liner, for example, a release liner having a release layer (release treatment layer) on at least one surface of a release liner base material, a release liner of low adhesiveness containing a fluorine-based polymer, and a release liner containing Non-polar polymer release liner with low adhesion, etc. Furthermore, the release liner base material which does not have a release layer (that is, the release liner base material itself) can also be mentioned. The fluorine-based polymer is not particularly limited, and examples thereof include polytetrafluoroethylene, polychlorotrifluoroethylene, polyvinyl fluoride, polyvinylidene fluoride, tetrafluoroethylene-hexafluoropropylene copolymer, and chlorofluoroethylene- Vinylidene fluoride copolymer, etc. Moreover, it does not specifically limit as said non-polar 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 substrate with a release layer on at least one surface of the release liner substrate, and a release liner substrate without a release layer (that is, the release liner substrate itself).

It does not specifically limit as said release liner base material, Plastic film etc. are mentioned. As such a plastic film, for example, a plastic film including the following: polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT) And other polyester resins; polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), etc. Body composition olefin resin; polyvinyl chloride (PVC); vinyl acetate resin; polycarbonate (PC); polyphenylene sulfide (PPS); polyamide (nylon), fully aromatic polyamide (aromatic Amine-based resins such as polyamides); polyimine-based resins; polyether ether ketone (PEEK), etc. Among them, from the viewpoints of self-processability, availability, workability, dust resistance, cost, etc., a plastic film containing a polyester resin is preferred, More preferably, it is a PET film.

The release treatment agent constituting the release layer is not particularly limited, and examples thereof include release treatment agents such as silicone-based release treatment agents, fluorine-based release treatment agents, long-chain alkyl-based release treatment agents, and molybdenum sulfide. In addition, a peeling treatment agent can be used individually or in combination of 2 or more types.

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

(Polysiloxane adhesive tape)

The manufacturing method of the silicone adhesive tape of the present invention is not particularly limited, and a known forming method can be used. For example, it can be produced by forming a silicone adhesive layer A from the silicone adhesive composition A on at least one side of the base film.

The initial adhesion of the silicone adhesive tape of the present invention (especially the initial adhesion of the adhesive surface provided by the silicone adhesive layer A) is 0.01~0.10N/25mm, preferably 0.01~0.08N/ 25mm, more preferably 0.01~0.05N/25mm. The initial adhesive force of the silicone adhesive tape of the present invention is 0.01N/25mm or more, so sufficient adhesiveness to the adherend can be obtained. In addition, since the initial adhesive force is 0.10N/25mm or less, it is lightly peeled from the adherend, and the adhesive force to the adherend is small. Therefore, even if it is attached to the adherend, it can be easily peeled off from the adherend without breaking the adherend. Furthermore, the initial adhesive force refers to the adhesive force when the unattached or preserved adhesive tape is attached to the adherend. The initial adhesive force is determined by measuring the adhesive force when peeling off the adhesive tape 30 minutes after attaching the adhesive tape to the adherend. The above-mentioned initial adhesion force is the adhesion force to the glass plate measured under the peeling conditions of tensile speed: 300mm/min and peeling angle: 180°. In addition, it was measured under an environment of measurement temperature: 23°C and relative humidity: 50% RH. In addition, as the glass plate, for example, a glass plate (soda lime glass #0050, manufactured by Songlang Glass Industry Co., Ltd.) can be cited.

The silicone adhesive tape of the present invention preferably has a value of the following formula (1) of 80 or less.

(Adhesion A)/(Adhesion B)×100 (1)

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

Adhesion B: The adhesive tape on the surface of the substrate film with a silicone adhesive layer that does not contain a silicone release agent is attached to the glass, and the glass is adhered to the glass after storage at 85°C for 48 hours force

Adhesive force A and adhesive force B are measured under the conditions of peeling speed: 300mm/min and peeling angle: 180° to the glass plate. In addition, it was measured under an environment of measurement temperature: 23°C and relative humidity: 50% RH.

As the glass plate, for example, a glass plate (soda lime glass #0050, manufactured by Songlang Glass Industry Co., Ltd.) can be cited.

The adhesive tape used in the measurement of the adhesive force A is an adhesive tape with a silicone adhesive layer containing a silicone release agent on at least one side of the base film, and in the measurement of the adhesive force B The adhesive tape used is an adhesive tape with a silicone-based adhesive layer that does not contain a silicone-based release agent on at least one side of the base film. If the adhesive tape used in the measurement of the adhesive force A is compared with the adhesive tape used in the measurement of the adhesive force B, it will be all except whether the silicone-based adhesive layer contains a silicone-based release agent or not. the same. For example, regarding the adhesive tape used in the measurement of the adhesive force A and the adhesive tape used in the measurement of the adhesive force B, the thickness of the silicone adhesive layer is the same, and the material or thickness of the base film is the same.

Furthermore, the 48-hour storage at 85°C is equivalent to the long-term storage at room temperature.

In the silicone adhesive tape of the present invention, the value of formula (1) is 80 or less, preferably 75 or less. The value of formula (1) of the silicone adhesive tape of the present invention is 80 or less, so the increase of the adhesive force over time is suppressed, the fixed adhesive force can be maintained, and the fixed adhesive force can be maintained even if stored over time force.

In addition, the silicone adhesive tape of the present invention is preferably transparent.

The haze (according to JIS K7136) of the silicone adhesive tape of the present invention is not particularly limited. In terms of obtaining higher transparency, it is preferably 1.5% or less, more preferably 1.0% or less. Furthermore, for haze, for example, the silicone adhesive tape of the present invention can be attached to a glass slide (for example, with a total light transmittance of 91.8% and a haze of 0.4%), using a haze meter (Murakami Color Technology Manufactured by Research Institute Co., Ltd., trade name "HM-150") and measured.

In addition, the transmittance of the silicone adhesive tape of the present invention (total light transmittance in the visible light wavelength region, according to JIS K7361-1) is not particularly limited, but in terms of obtaining higher transparency, it is preferably 80% or more, more preferably 85% or more. Furthermore, the transmittance can be, for example, the silicone adhesive tape of the present invention can be attached to a glass slide (for example, the total light transmittance is 91.8%, the haze is 0.4%), and the haze meter (Murakami Color Technology Manufactured by Research Institute Co., Ltd., trade name "HM-150") and measured.

The thickness of the silicone adhesive tape of the present invention is not particularly limited, and is preferably 15 to 400 μm, more preferably 20 to 300 μm, and still more preferably 25 to 250 μm.

The silicone adhesive tape of the present invention has the silicone adhesive layer A, so it exhibits sufficient adhesiveness to the adherend, and the increase in adhesive force over time is suppressed. In addition, it is lightly peeled from the adherend, and even after being stored for a long period of time, it is lightly peeled from the adherend. Therefore, the silicone adhesive tape of the present invention can maintain a fixed adhesive force for a long period of time. Therefore, the silicone adhesive tape of the present invention can be easily peeled off from the adherend without breaking the adherend even after a long period of time after being attached to the adherend. That is, the silicone adhesive tape of the present invention has excellent releasability.

For example, even if the polysiloxane adhesive tape of the present invention is attached to a fragile adherend such as a semiconductor wafer with a small thickness for a long time, the polysiloxane adhesive tape of the present invention can be easily peeled from the adherend Silicone adhesive tape does not damage the adherend.

The silicone adhesive tape of the present invention has the above-mentioned characteristics, so it can be preferably used as a surface protective film. For example, it can be preferably used for surface protection purposes of thin-layer display members, thin-layer display devices, thin-layer optical films, electronic devices, and the like. As the above-mentioned thin-layer display device, there is no special Without limitation, a touch panel using LCD (Liquid Crystal Display, liquid crystal display device) or the like can be preferably cited. The above-mentioned thin-layer display member is not particularly limited, and preferably includes LCDs or color filters used therein. It does not specifically limit as said thin-layer optical film, Preferably, a polarizing plate is mentioned.

[Example]

Hereinafter, examples and comparative examples are given to further specifically describe the present invention. The present invention is not limited by these.

(Example 1)

Polysiloxane adhesive 1 (addition reaction type polysiloxane adhesive, trade name "X-40-3306", manufactured by Shin-Etsu Chemical Co., Ltd.): 100 parts by weight, platinum catalyst 1 (commodity Name "CAT-PL-50T", manufactured by Shin-Etsu Chemical Industry Co., Ltd.): 0.4 parts by weight, polysiloxane stripping agent 1 (addition reaction type polysiloxane based on dimethylpolysiloxane as the main component Release agent, trade name "KS-776A", manufactured by Shin-Etsu Chemical Industry Co., Ltd.): 0.5 parts by weight were mixed to prepare a silicone adhesive composition (polysilicone adhesive composition 1).

On the base film 1 (polysilicone primer treated polyester film on one side, thickness 38μm, trade name "DIAFOIL MRF#38", manufactured by Mitsubishi Plastics Co., Ltd.), the topcoat treated with silicone primer The silicone adhesive composition 1 is applied to obtain a film having a silicone adhesive composition layer.

Secondly, the above-mentioned film with the silicone adhesive composition layer is heated and dried as follows, namely, heating under the conditions of temperature: 30°C, time: 2 minutes, and then at temperature: 130°C, time: Heating is performed for 3 minutes to form a silicone adhesive layer with a thickness of 75 μm. Then, a silicone adhesive tape having a silicone adhesive layer on one side of the base film is obtained.

Furthermore, a polyethylene terephthalate film (polyethylene terephthalate film without peeling treatment) is attached to the adhesive surface of the silicone adhesive tape to protect the silicone adhesive layer .

(Example 2)

Except that the amount (parts of addition) of the silicone release agent 1 was 1.0 part by weight, a silicone adhesive composition (polysilicone adhesive composition) was prepared in the same manner as in Example 1. 2).

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

(Example 3)

Except that the amount (parts of addition) of the silicone release agent 1 was set to 3.0 parts by weight, a silicone adhesive composition (polysilicone adhesive composition) was prepared in the same manner as in Example 1. (Polysiloxane adhesive composition 3).

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

(Example 4)

Except that the amount (parts of addition) of the silicone release agent 1 was 5.0 parts by weight, a silicone adhesive composition (polysilicone adhesive composition) was prepared in the same manner as in Example 1. (Polysiloxane adhesive composition 4).

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

(Example 5)

Except that the amount (parts of addition) of the silicone release agent 1 was set to 10.0 parts by weight, a silicone adhesive composition (polysilicone adhesive composition) was prepared in the same manner as in Example 1. (Polysiloxane adhesive composition 5).

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

(Example 6)

Set the amount of silicone release agent 1 (additional parts) to 30.0 parts by weight. In addition, A silicone adhesive composition (polysilicone adhesive composition (polysilicone adhesive composition 6) was prepared in the same manner as in Example 1.

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

(Example 7)

Except that the amount (parts of addition) of the silicone release agent 1 was set to 50.0 parts by weight, a silicone adhesive composition (polysilicone adhesive composition was prepared in the same manner as in Example 1). (Polysiloxane adhesive composition 7).

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

(Example 8)

The silicone adhesive composition 2 was used, and the thickness of the adhesive composition 2 after drying was set to 10 μm. In the same manner as in Example 1, a silicone adhesive tape was obtained.

(Example 9)

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

(Comparative example 1)

Except that the silicone release agent 1 was not added, a silicone adhesive composition (polysilicone adhesive composition (polysilicone adhesive composition 8) was prepared in the same manner as in Example 1 .

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

(Comparative example 2)

Except that the amount (parts of addition) of the silicone release agent 1 was set to 0.1 part by weight, a silicone adhesive composition (polysilicone adhesive composition) was prepared in the same manner as in Example 1. (Polysiloxane adhesive composition 9).

The silicone adhesive composition 9 was used, except that it was obtained in the same manner as in Example 1. Get silicone adhesive tape.

(Comparative example 3)

Except for using silicone adhesive composition 8, a silicone adhesive tape was prepared in the same manner as in Example 8.

(Comparative Example 4)

Except for using silicone adhesive composition 9, a silicone adhesive tape was prepared in the same manner as in Example 8.

[Measurement]

Using the following adhesive force measurement method, the initial adhesive force, adhesive force A, and adhesive force B were obtained for the silicone adhesive tapes obtained in the examples and comparative examples. Furthermore, the value of formula (1) [(adhesive force A)/(adhesive force B)×100] is obtained from the adhesive force A and adhesive force B.

Furthermore, the silicone adhesive layer was attached to a glass slide (total light transmittance of 91.8%, haze of 0.4%) to prepare a measurement sample, and a haze meter (Murakami Color Technology Research Institute Co., Ltd. Manufacture, trade name "HM-150"). From the measurement sample, the haze of the silicone adhesive layer and the total light transmittance of the silicone adhesive layer are calculated.

(Measurement method of adhesion)

After placing the silicone adhesive tape in an environment of 23°C and 50% RH for 30 minutes, a sheet with a length of 100 mm and a width of 25 mm was obtained from the silicone adhesive tape. Next, in an environment of 23°C and 50% RH, the release liner was peeled from the above-mentioned sheet to expose the adhesive surface (measurement surface), and the sheet was pressure-bonded to the glass plate (sodium Lime Glass #0050, manufactured by Songlang Glass Industry Co., Ltd.), so that the sheet is attached to the glass plate. Next, a 180° peel test was performed using a tensile tester (trade name "TCM-1kNB", manufactured by Minebea), and the 180° peel adhesion strength (180° peel adhesion strength) (N/25mm) was measured. The measurement is performed under the conditions of 23°C and 50%RH under the conditions of a peeling angle of 180° and a stretching speed of 300mm/min.

(Initial adhesion)

After the silicone adhesive tape is made, the adhesive force of the silicone adhesive tape is obtained by the above-mentioned adhesive force measurement method. Let this adhesive force be the initial adhesive force.

In addition, the initial adhesion is measured by bonding the sheet to the glass plate and leaving it for 30 minutes, and then performing a 180° peel test.

(Adhesion A)

After making the silicone adhesive tape, place it at 85°C for 48 hours to form the silicone adhesive tape after heating. According to the above-mentioned adhesive force measurement method, the adhesive force was obtained for the silicone adhesive tape after heating and standing. Let this adhesive force be adhesive force A.

(Adhesion B)

Regarding the examples and comparative examples related to the silicone adhesive tape containing the silicone release agent in the silicone adhesive layer, except for the addition of the silicone release agent, the same procedures were used to produce and implement each The silicone adhesive tape corresponding to the example and the comparative example is used as a reference.

The silicone adhesive tape used as a reference is in the silicone adhesive layer and does not contain a silicone release agent. Except for whether it contains a silicone release agent, it is in accordance with the corresponding examples or comparative examples. The silicone adhesive tape is the same.

After making the reference silicone adhesive tape, place it at a temperature of 85°C for 48 hours to prepare the reference silicone adhesive tape after heating and standing. According to the above-mentioned adhesive force measurement method, the adhesive force was obtained for the reference silicone adhesive tape after heating and standing. Let this adhesive force be adhesive force B.

Furthermore, regarding a comparative example that does not contain a silicone-based release agent, the value of adhesive force A is used as the value of adhesive force B for convenience.

In Table 1, "A/B×100" means "the value of formula (1) [(adhesive force A)/(adhesive force B)×100]".

Claims (9)

A polysiloxane adhesive tape, which is characterized in that: at least one side of a substrate film is provided with a polysiloxane containing a polysiloxane adhesive, an addition reaction type polysiloxane release agent, and a platinum catalyst The silicone-based adhesive layer formed by the adhesive composition. The silicone-based release agent contains polysiloxane (containing Si) with hydrogen atoms (H) bonded to silicon atoms (Si) in the molecule. -H-based polysiloxane), and polysiloxane (Si-H-based reactive functional group) that contains a functional group (Si-H reactive functional group) that is reactive to Si-H bonds (the covalent bond between Si and H) in the molecule ( Si-H-based reactive polysiloxane) release agent, and the initial adhesion is 0.01~0.10N/25mm, the value of the following formula (1) is 80 or less, (adhesive force A)/(adhesive force B) ×100 (1), Adhesion A: Adhesion to glass after being attached to glass and stored at 85°C for 48 hours, Adhesion B: A side of the base film that does not contain silicone The adhesive tape of the polysiloxane adhesive layer of the release agent is attached to the glass, and the adhesive force to the glass after being stored at 85°C for 48 hours. Such as the silicone adhesive tape of claim 1, wherein the content of the silicone release agent in the silicone adhesive layer is 0.2 parts by weight or more and 100 parts by weight relative to 100 parts by weight of the silicone adhesive The following. For example, the silicone adhesive tape of claim 1 or 2, wherein the haze of the silicone adhesive layer is 1.5% or less. The silicone adhesive tape of claim 1 or 2, wherein the base film is a polyester film. Such as the silicone adhesive tape of claim 3, wherein the above-mentioned base film is a polyester film. The polysiloxane adhesive tape of claim 1 or 2, wherein the polysiloxane release agent contains polydimethylsiloxane and polydimethylsiloxane containing Si-H reactive functional groups alkyl. The silicone adhesive tape of claim 3, wherein the silicone release agent includes polydimethylsiloxane and polydimethylsiloxane containing Si-H reactive functional groups. The silicone adhesive tape of claim 4, wherein the silicone release agent includes polydimethylsiloxane and polydimethylsiloxane containing Si-H reactive functional groups. The polysiloxane-based adhesive tape of claim 5, wherein the polysiloxane-based release agent contains polydimethylsiloxane and polydimethylsiloxane containing Si-H reactive functional groups.