TWI741115B - Surface protection film - Google Patents

Abstract

The subject of the present invention is to provide a surface protective film for optics with a separator, which is configured to prevent the separation of The peeling force of the adhesive layer makes it excellent in peelability and workability, and the use of a separator with holes and excellent cushioning properties can suppress the generation of dents caused by the separator.

The solution of the present invention is a surface protection film for optics with a separator, which has a surface protection film for optics and a separator. The surface protection film for optics is a substrate film with an adhesive layer on at least one side, and The separator is located on the opposite side of the surface of the adhesive layer in contact with the substrate film; the optical surface protection film with separator is characterized in that the separator has a mold release layer and a polyester-based substrate. The polyester-based substrate has holes, the thickness of the polyester-based substrate is 25-100 μm, and the 180° initial peeling force of the separator to the adhesive layer is less than 0.7N/50mm.

Description

Surface protection film

The present invention relates to a surface protective film for optics with a separator. Especially for optical surface protection films used to protect the surface of optical components (such as polarizing plates, wave plates, phase difference plates, optical compensation films, reflectors, brightness enhancement films, etc. used in liquid crystal displays, etc.) by attaching (Laminated) The specific separator is useful for protecting the surface of the adhesive layer constituting the aforementioned optical surface protection film until it is actually used. It can provide excellent peelability and workability, and can prevent the generation of dents, which is useful.

Background Art Surface protection films generally have a configuration in which an adhesive layer is provided on a film-like base film (support). The surface protection film is bonded to the attached optical member through the aforementioned adhesive layer, thereby protecting the surface of the optical member from scratches or dirt during processing, transportation, inspection, etc. use. For example, a liquid crystal display panel is formed by bonding optical members such as a polarizing plate or a wave plate to a liquid crystal cell through an adhesive layer. The pressure-sensitive adhesive layer is protected and stored by a mold release process, etc. from the perspective of the necessity of protection from drying before it is actually bonded to the optical member (Patent Document 1).

After that, when the adhesive layer surface of the aforementioned surface protection film is actually attached to the optical member and used, the release sheet will be peeled and removed.

Prior Art Documents Patent Documents Patent Document 1: JP 2012-224811

Summary of the invention

In addition, when the separator is thick, the peeling force (adhesive force) of the separator to the adhesive layer constituting the surface protection film during peeling and removal becomes high, which may cause problems of poor peelability or workability.

In addition, if a thinner separator is used instead of a thicker separator for adhesive coating, the particles (such as polyester-based fillers, etc.) contained in the base material of the separator adhered to the surface of the separator. ), which is the cause of dents on the surface of the adhesive layer when the adhesive layer is formed. In addition, when the separator is attached to the attached body with dents on the surface of the adhesive layer, air bubbles will enter the dent portion (space) between the adhesive layer and the attached body, resulting in an inspection substrate. A problem that deteriorates the inspection performance when possessing the body.

Therefore, the inventors of the present invention have made diligent studies in view of the above situation, and their object is to provide a surface protective film for optics with a separator, which is composed of a polyester-based substrate laminated on the separator of the optical surface protective film. Thickness and holes are provided to weaken the stiffness (rigidity) of the separator, and the peeling force of the separator to the adhesive layer can be suppressed, so that the peelability and workability are excellent, and the hole has excellent cushioning properties, which can inhibit separation The occurrence of dents caused by the parts makes the inspection excellent.

That is, the optical surface protective film with a separator of the present invention has an optical surface protective film and a separator, and the optical surface protective film has an adhesive layer on at least one side of the base film, and the separator The surface of the adhesive layer that is in contact with the substrate film is the opposite side; the optical surface protection film with a separator is characterized in that the separator has a mold release layer and a polyester-based substrate, and the polyester The base material has holes, the thickness of the polyester base material is 25-100 μm, and the 180° initial peeling force of the separator to the adhesive layer is less than 0.7N/50mm.

In the surface protective film for optics with a separator of the present invention, the porosity of the polyester-based substrate is preferably 15% or more relative to the volume of the aforementioned polyester-based substrate.

In the optical surface protection film with a separator of the present invention, the aforementioned base film is preferably a polyester film.

In the optical surface protection film with a separator of the present invention, the adhesive layer is preferably formed of an adhesive composition containing a (meth)acrylic polymer.

In the present invention, by specifying the thickness of the polyester base material constituting the separator layered on the optical surface protection film and providing holes, the release force of the separator on the adhesive layer constituting the optical surface protection film is suppressed, and the releasability is improved. Excellent workability, and the use of separators with holes and excellent cushioning properties can suppress the occurrence of dents caused by the separators, and can produce excellent optical surface protection films in the state where the optical surface protection film is attached to the attached body. The optical surface protective film with separate parts for inspection is useful.

Modes for Carrying Out the Invention Hereinafter, embodiments of the present invention will be described in detail.

<The overall structure of the optical surface protective film with a separator> The optical surface protective film with a separator disclosed here (hereinafter, sometimes referred to as "surface protective film") is generally called an adhesive tape , Adhesive labels, adhesive films, etc. The surface of the adhesive layer is protected by a separator, and it is especially suitable as an optical component used as a component of a liquid crystal display panel in the processing, inspection, and transportation of optical parts (such as polarizers, wave plates, etc.) Part) is a surface protective film that protects the surface of optical parts. The adhesive layer of the aforementioned surface protection film is typically formed continuously, but it is not limited to this form. For example, it may be an adhesive layer that forms regular or random patterns such as dots and stripes. In addition, the surface protection film disclosed here may also be in the form of a roll or a single sheet.

<Substrate film> The optical surface protective film constituting the optical surface protective film with a separator of the present invention is characterized by having a substrate film. In the technique disclosed herein, although the resin material constituting the base film can be used without particular limitation, it is preferable to use such materials as transparency, mechanical strength, thermal stability, moisture resistance, isotropy, flexibility, and size. Those with excellent stability and other characteristics. In particular, since the substrate has flexibility, it can be coated with an adhesive composition by a roll coater or the like, and can be wound into a roll, which is useful.

For the aforementioned base film (support), a plastic film composed of the following resin material can be suitably used as the aforementioned base film, such as polyethylene terephthalate (PET), poly Polyester-based polymers such as ethylene naphthalate (PEN) and polybutylene terephthalate; cellulose-based polymers such as diacetyl cellulose and triacetyl cellulose; polycarbonate-based polymerization Materials; acrylic polymers such as polymethyl methacrylate are the main resin component (the main component of the resin component is typically a component that occupies 50% by weight or more). Other examples of the aforementioned resin materials include the following as resin materials: polystyrene, styrene-based polymers such as acrylonitrile-styrene copolymers; polyethylene, polypropylene, polystyrenes having cyclic or norbornene structures Olefin-based polymers such as olefins and ethylene-propylene copolymers; vinyl chloride polymers; amide-based polymers such as nylon 6, nylon 6,6, aromatic polyamides, etc. Still other examples of the aforementioned resin materials include imine-based polymers, tungsten-based polymers, polyether-tungsten-based polymers, polyether ether ketone-based polymers, polyphenylene sulfide-based polymers, and vinyl alcohol-based polymers. , Vinylidene chloride polymer, vinyl butyral polymer, aryl ester polymer, polyoxymethylene polymer, epoxy polymer, etc. It may also be a base film composed of a mixture of two or more of the above-mentioned polymers.

As the aforementioned base film, a plastic film made of a transparent thermoplastic resin can be suitably used. Among the aforementioned plastic films, a polyester film is preferably used. Here, polyester film refers to a main skeleton based on ester bonds such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polybutylene terephthalate. The polyester-based polymer material (polyester resin) as the main resin component. The polyester film has excellent optical properties, dimensional stability, and other preferable properties as a base film of a surface protection film.

The resin material constituting the aforementioned base film can also be blended with various additives such as antioxidants, ultraviolet absorbers, plasticizers, colorants (pigments, dyes, etc.) as needed. Well-known or customary surface treatments such as corona discharge treatment, plasma treatment, ultraviolet irradiation treatment, acid treatment, alkali treatment, and primer coating can be applied. The surface treatment can be used to improve the adhesion between the substrate film and the adhesive layer (anchoring property of the adhesive layer), for example.

The aforementioned base film can also be a plastic film applied with antistatic treatment. By using the aforementioned base film, it is possible to suppress the charging of itself when peeling off the surface protective film, which is preferable. In addition, the base film is a plastic film, and by applying antistatic treatment to the plastic film, the charge of the surface protection film itself can be reduced, and an excellent antistatic ability to the attached body can be obtained. In addition, the method of imparting antistatic function is not particularly limited, and well-known methods can be used, such as coating with antistatic resin composed of antistatic agent and resin component, or conductive polymer containing conductive polymer and conductive material. The method of resin, or the method of vapor deposition or electroplating of conductive material, can also include the method of mixing antistatic agent, etc.

The thickness of the aforementioned substrate film is usually 5 to 200 μm, preferably about 10 to 100 μm. When the thickness of the aforementioned base film is within the aforementioned range, the workability for attaching to the attached body and the releasability or workability for peeling from the attached body are excellent, which is preferable.

The surface protection film disclosed herein can be obtained by implementing in a manner including other layers in addition to the base film, the adhesive layer, and the separator. Examples of the aforementioned other layer include an undercoating layer (anchoring layer) that can improve the anchoring properties of the antistatic layer or the adhesive layer.

<Adhesive layer> The adhesive used in the present invention can be used without particular limitation as long as it is formed of an adhesive composition containing an adhesive polymer having adhesiveness. For the aforementioned adhesive composition, for example, acrylic adhesives, urethane adhesives, synthetic rubber adhesives, natural rubber adhesives, silicone adhesives, polyester adhesives, etc. can be used. It is better to use (contain) at least one selected from the group consisting of acrylic adhesives, urethane adhesives and silicone adhesives, and use ( The adhesive composition of the meth)acrylic polymer (acrylic adhesive) is particularly preferred.

When an acrylic adhesive is used for the aforementioned adhesive layer, the (meth)acrylic polymer constituting the adhesive polymer of the aforementioned acrylic adhesive can be used as a (meth)acrylic monomer having a C1-C14 alkyl group. The body is used as the main monomer as its raw material. The aforementioned (meth)acrylic monomers can be used singly or in two or more types. By using the (meth)acrylic monomer with the aforementioned C1-C14 alkyl group, the peeling force (adhesive force) to the attached body (protected body) can be easily controlled to be low, and light weight can be obtained. A surface protective film with excellent peelability or repeelability. In addition, the (meth)acrylic polymer in the present invention refers to acrylic polymer and/or methacrylic polymer, and (meth)acrylate refers to acrylate and/or methacrylate .

Specific examples of the aforementioned (meth)acrylic monomers containing an alkyl group with 1 to 14 carbon atoms include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, (Meth) butyl acrylate, tertiary butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, ( N-octyl (meth)acrylate, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, iso-octyl (meth)acrylate Decyl ester, n-dodecyl (meth)acrylate, n-tridecyl (meth)acrylate, n-tetradecyl (meth)acrylate, etc.

Among them, in the surface protective film of the present invention, especially n-butyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, and n-octyl (meth)acrylate can be mentioned. Ester, isooctyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, (meth) ) (Meth)acrylic monomers containing an alkyl group with 4 to 14 carbon atoms, such as n-dodecyl acrylate, n-tridecyl (meth)acrylate, and n-tetradecyl (meth)acrylate, are preferred. In particular, by using the aforementioned (meth)acrylic monomer containing an alkyl group with 4 to 14 carbon atoms, the peeling force (adhesive force) to the adherend can be easily controlled to be low, and it is the one with excellent re-peelability .

In particular, it is preferable to use a (meth)acrylic monomer containing 65% by weight or more of a C1-C14 alkyl group with respect to 100% by weight of the total amount of monomer components constituting the aforementioned (meth)acrylic polymer. It is preferably 75% by weight or more, more preferably 85 to 99.9% by weight, and most preferably 90 to 99% by weight. When it is less than 50% by weight, the appropriate wettability of the adhesive composition or the cohesive force of the adhesive layer will deteriorate, which is not good.

In addition, the aforementioned (meth)acrylic polymer can use a hydroxyl group-containing (meth)acrylic monomer as a raw material monomer. The above-mentioned hydroxyl group-containing (meth)acrylic monomer can be used singly or in two or more types. By using the aforementioned hydroxyl-containing (meth)acrylic monomers, it is easy to control the crosslinking of the adhesive composition, and it is easier to control the use of flow to improve the wettability and the peeling force (adhesive force) at the time of peeling. balance.

The aforementioned hydroxyl-containing (meth)acrylic monomers include, for example, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 4-hydroxybutyl (meth)acrylate , 6-hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 10-hydroxydecyl (meth)acrylate, 12-hydroxylauryl (meth)acrylate, (4 -Hydroxymethylcyclohexyl)methacrylate, N-hydroxymethyl(meth)acrylamide, etc.

With respect to 100% by weight of the total amount of monomer components constituting the (meth)acrylic polymer, it is preferable to contain 25% by weight or less of the hydroxyl-containing (meth)acrylic monomer, preferably 15% by weight Hereinafter, it is more preferably 0.1 to 10% by weight. If it is within the aforementioned range, the balance between the wettability of the adhesive composition and the cohesive force of the obtained adhesive layer can be easily controlled, which is preferable.

In addition, as other polymerizable monomer components, for the reason that the balance of adhesive properties is easily obtained, in order to make Tg below 0°C (usually above -100°C), it can be used within a range that does not impair the effects of the present invention. To adjust the glass transition temperature of the (meth)acrylic polymer or releasable polymerizable monomers.

In addition, the aforementioned (meth)acrylic polymer can use a carboxyl group-containing (meth)acrylic monomer as a raw material monomer. By using the (meth)acrylic monomer containing the aforementioned carboxyl group, the increase in the adhesive force of the adhesive layer (surface protective film) over time can be suppressed, and re-peelability, increase in adhesion resistance and workability can be achieved Excellent. Moreover, in addition to the excellent cohesive force of the adhesive layer, the shearing force is also excellent, which is preferable.

Examples of the aforementioned carboxyl group-containing (meth)acrylic monomer include (meth)acrylic acid, carboxyethyl (meth)acrylate, and carboxypentyl (meth)acrylate.

With respect to 100% by weight of the total amount of monomer components constituting the (meth)acrylic polymer, the carboxyl group-containing (meth)acrylic monomer is preferably 10% by weight or less, more preferably 0-8% by weight, More preferably, it is 0 to 6 wt%. If it is within the aforementioned range, the balance between the wettability of the adhesive composition and the cohesive force of the obtained adhesive layer can be easily controlled, which is preferable.

Moreover, as long as it is in the range which does not impair the characteristic of this invention, the said (meth)acrylic-type polymer can use the polymerizable monomer other than the said raw material monomer without a restriction|limiting in particular. For example, the aforementioned other polymerizable monomers can be suitably used to improve cohesiveness and heat resistance such as cyano group-containing monomers, vinyl ester monomers, aromatic vinyl monomers, or amide group-containing monomers and amide group-containing monomers. , Amine group-containing monomers, epoxy group-containing monomers, N-acryloyl morpholine, vinyl ether monomers, etc., have functional groups that enhance the peeling force (adhesion) and can act as crosslinking base points. Element. Among them, nitrogen-containing monomers such as cyano group-containing monomers, amide group-containing monomers, amide group-containing monomers, amine group-containing monomers, and N-acrylomorpholine are preferably used. By using a nitrogen-containing monomer, it is possible to ensure a moderate peeling force (adhesive force) that does not produce bumps or peeling, and to obtain a surface protective film with excellent shearing force, which is useful. One type or two or more types of these polymerizable monomers can be used.

Examples of the aforementioned cyano group-containing monomer include acrylonitrile and methacrylonitrile.

The aforementioned amine group-containing monomers include, for example, acrylamide, methacrylamide, diethylacrylamide, N-vinylpyrrolidone, N,N-dimethylacrylamide, N,N- Dimethylmethacrylamide, N,N-diethylacrylamide, N,N-diethylmethacrylamide, N,N'-methylenebisacrylamide, N,N- Dimethylaminopropyl acrylamide, N,N-dimethylaminopropyl methacrylamide, diacetone acrylamide, etc.

Examples of the above-mentioned iminium group-containing monomer include cyclohexylmaleimide, isopropylmaleimide, N-cyclohexylmaleimide, and Iconimide.

The aforementioned amine group-containing monomers include, for example, aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, N,N-dimethylaminopropyl ( Meth) acrylate and the like.

Examples of the aforementioned vinyl ester monomer include vinyl acetate, vinyl propionate, and vinyl laurate.

Examples of the aforementioned aromatic vinyl monomer include styrene, chlorostyrene, chloromethylstyrene, α-methylstyrene, and other substituted styrenes.

Examples of the epoxy group-containing monomer include glycidyl (meth)acrylate, methylglycidyl (meth)acrylate, and allylglycidyl ether.

Examples of the aforementioned vinyl ether monomer include methyl vinyl ether, ethyl vinyl ether, and isobutyl vinyl ether.

In the present invention, the other polymerizable monomer is preferably 0 to 30% by weight, more preferably 0 to 10% by weight, relative to 100% by weight of the total amount of monomer components constituting the (meth)acrylic polymer. The aforementioned other polymerizable monomers can be adjusted appropriately in order to obtain desired characteristics.

The aforementioned (meth)acrylic polymer may further contain an epoxy group-containing reactive monomer as a monomer component.

In addition, from the viewpoint of compatibility with the oxygen-containing alkylene compound, the average number of additions and moles of the oxyalkylene unit of the above-mentioned oxyalkylene-containing reactive monomer is preferably 1-40, which is more It is preferably 3~40, more preferably 4~35, especially 5~30. When the aforementioned average added mole number is 1 or more, there is a tendency that the effect of reducing the pollution of the attached body (protected body) can be obtained efficiently. In addition, when the aforementioned average added molar number is greater than 40, the interaction with the oxygen-containing alkylene compound will increase, which will increase the viscosity of the adhesive composition and make it difficult to apply, which is not preferable. In addition, the end of the oxyalkylene chain may be a hydroxyl group, or may be substituted by other functional groups or the like.

The aforementioned reactive monomer containing alkylene oxide can be used alone or in combination of two or more, but the total content is preferably in the total amount of monomer components of the aforementioned (meth)acrylic polymer 0-20% by weight, preferably 0-10% by weight. If the content of the epoxy alkyl-containing reactive monomer exceeds 20% by weight, the pollution to the attached body will deteriorate, which is not good.

The oxyalkylene unit of the reactive monomer containing an epoxy group may include those having a carbon number of 1 to 6, such as oxymethylene, oxyethylene, oxyethylene, and oxygen. Butylene and so on. The hydrocarbon group of the oxyalkylene chain may be straight or branched.

In addition, the aforementioned reactive monomer containing an epoxy group is more preferably a reactive monomer having an epoxy group. By using a (meth)acrylic polymer containing a reactive monomer with an oxirane group as the base polymer, the compatibility between the base polymer and the oxygen-containing alkylene compound can be improved, and the adhesion to the The body oozes out, and a low-polluting adhesive composition is obtained.

The aforementioned reactive monomers containing alkylene oxide include, for example, (meth)acrylic acid alkylene oxide adducts, or reactions with reactive substituents such as acrylic, methacrylic, and allyl groups in the molecule. Surfactant, etc.

Specific examples of the aforementioned (meth)acrylic acid alkylene oxide adduct include, for example, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, and polyethylene glycol-polypropylene glycol (meth)acrylic acid. Ester, polyethylene glycol-polybutylene glycol (meth)acrylate, polypropylene glycol-polybutylene glycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, ethoxylated poly Ethylene glycol (meth) acrylate, butoxy polyethylene glycol (meth) acrylate, octyloxy polyethylene glycol (meth) acrylate, lauryloxy polyethylene glycol (meth) acrylic acid Esters, stearyloxy polyethylene glycol (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate, methoxy polypropylene glycol (meth) acrylate, octyloxy polyethylene glycol -Polypropylene glycol (meth)acrylate and the like.

In addition, specific examples of the aforementioned reactive surfactants include, for example, anionic reactive surfactants having (meth)acryloyl or allyl groups, nonionic reactive surfactants, and cationic reactive surfactants.剂 etc.

The weight average molecular weight (Mw) of the aforementioned (meth)acrylic polymer is preferably 100,000 to 5 million, preferably 200,000 to 4 million, more preferably 300,000 to 3 million, and most preferably 300,000 to 120 ten thousand. When the weight-average molecular weight is less than 100,000, the cohesive force of the adhesive layer will decrease, which will result in residual glue. On the other hand, when the weight average molecular weight exceeds 5 million, the fluidity of the polymer will decrease, and the wetting of the attached body (such as the polarizing plate) will become insufficient, which may cause the adhesive between the attached body and the surface protective film The tendency to cause expansion between layers. In addition, the weight average molecular weight refers to the one measured by GPC (gel permeation chromatography).

In addition, the glass transition temperature (Tg) of the aforementioned (meth)acrylic polymer is preferably 0°C or lower, and more preferably 10°C or lower (usually -100°C or higher). When the glass transition temperature is higher than 0°C, the polymer is not easy to flow, so that, for example, the wetting of the polarizing plate as an optical member becomes insufficient, which may cause swelling between the polarizing plate and the adhesive layer of the surface protection film Propensity. In particular, by setting the glass transition temperature to -70°C or less, an adhesive layer with excellent wettability and light peelability to the polarizing plate can be easily obtained. In addition, the glass transition temperature of the (meth)acrylic polymer can be adjusted within the aforementioned range by appropriately changing the monomer components or composition ratio used.

The polymerization method of the aforementioned (meth)acrylic polymer is not particularly limited. It can be polymerized by well-known methods such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization, etc., but especially from the viewpoint of workability or to the attached body ( From the viewpoint of low pollution and other characteristics of the protected body, solution polymerization is the preferred aspect. In addition, the obtained polymer may be any of random copolymers, block copolymers, alternating copolymers, graft copolymers, and the like.

<Oxygen-containing alkylene compound> The adhesive composition used in the present invention may contain an oxygen-containing alkylene compound. By containing an oxygen-containing alkylene compound, it can further exhibit light peeling properties. As the oxygen-containing alkylene compound, an organopolysiloxane having an oxyalkylene chain or an oxygen-containing alkylene compound not containing an organopolysiloxane can be cited.

Taking the specific example of the aforementioned organopolysiloxane having an oxyalkylene chain, as a specific example of the organopolysiloxane having an oxyalkylene chain in the main chain, for example, a commercial product under the trade name X- 22-4952, X-22-4272, X-22-6266, KF-6004, KF-889 (the above are made by Shin-Etsu Chemical Co., Ltd.), BY16-201, SF8427 (the above are made by Toray Dow Corning), IM22 (Made by Asahi Kasei Wacker Corporation), etc. In addition, specific examples of organopolysiloxanes having an oxyalkylene chain in the side chain include, for example, the trade names of commercially available products KF-351A, KF-352A, KF-353, KF-354L, KF-355A, KF-615A, KF-945, KF-640, KF-642, KF-643, KF-6022, X-22-6191, X-22-4515, KF-6011, KF-6012, KF-6015, KF- 6017, X-22-2516 (manufactured by Shin-Etsu Chemical Co., Ltd. above) SF8428, FZ-2162, SH3749, FZ-77, L-7001, FZ-2104, FZ-2110, L-7002, FZ-2122, FZ- 2164, FZ-2203, FZ-7001, SH8400, SH8700, SF8410, SF8422 (the above are manufactured by Toray‧Dow Corning), TSF-4440, TSF-4441, TSF-4445, TSF-4450, TSF-4446, TSF- 4452, TSF-4460 (manufactured by Momentive Performance Materials), BYK-333, BYK-307, BYK-377, BYK-UV3500, BYK-UV3570 (manufactured by BYK-Chemie Japan), etc. These compounds may be used alone, or two or more of them may be mixed and used.

Specific examples of the aforementioned oxygen-containing alkylene compound containing no organopolysiloxane include, for example, polyoxyalkylene alkylamine, polyoxyalkylene diamine, polyoxyalkylene fatty acid ester, and polyoxyalkylene Alkyl sorbitol fatty acid ester, polyoxyalkylene alkyl phenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene alkyl allyl ether, polyoxyalkylene alkyl phenylene Nonionic surfactants such as propyl ether; polyoxyalkylene alkyl ether sulfate salt, polyoxyalkylene alkyl ether phosphate salt, polyoxyalkylene alkyl phenyl ether sulfate, polyoxyalkylene Anionic surfactants such as oxyalkylene alkylphenyl ether phosphate salt; in addition, there are cationic surfactants or zwitterionic surfactants with polyoxyalkylene chains (polyalkylene oxide chains) , Polyether compounds with polyoxyalkylene chains (and their derivatives), acrylic compounds with polyoxyalkylene chains (and their derivatives), etc. In addition, a polyoxyalkylene chain-containing monomer may be blended as a polyoxyalkylene chain-containing compound. The polyoxyalkylene chain-containing compound may be used alone or in combination of two or more kinds.

Specific examples of the aforementioned polyether compound (polyether component) having a polyoxyalkylene chain include polypropylene glycol (PPG)-polyethylene glycol (PEG) block copolymers and PPG-PEG-PPG block copolymers. Copolymers, PEG-PPG-PEG block copolymers, etc. The derivatives of the aforementioned polyether compounds with polyoxyalkylene chains can include oxygen-containing propylene compounds whose ends are etherified (PPG monoalkyl ether, PEG-PPG monoalkyl ether, etc.), The oxygen-containing propylene compounds (terminally acetylated PPG, etc.) and so on.

In addition, examples of the acrylic compound having a polyoxyalkylene chain include (meth)acrylate polymers having an oxyalkylene chain. As the aforementioned oxyalkylene group, the number of added moles of the oxyalkylene unit is preferably 1-50, preferably 2-30, and more preferably 2-20. In addition, the terminal of the aforementioned oxyalkylene chain may be a hydroxyl group, or may be substituted by an alkyl group, a phenyl group, or the like.

The aforementioned (meth)acrylate polymer having an oxyalkylene group is preferably a polymer containing (meth)acrylic acid alkylene oxide as a monomer component. Taking the aforementioned (meth)acrylic acid alkylene oxide as a specific example, Examples of ethylene glycol group-containing (meth)acrylates include methoxy-diethylene glycol (meth)acrylate, methoxy-triethylene glycol (meth)acrylate, etc. -Polyethylene glycol (meth)acrylate type, ethoxy-polyethylene such as ethoxy-diethylene glycol (meth)acrylate, ethoxy-triethylene glycol (meth)acrylate, etc. Glycol (meth)acrylate type, butoxy-polyethylene glycol (butoxy-polyethylene glycol) such as butoxy-diethylene glycol (meth)acrylate and butoxy-triethylene glycol (meth)acrylate Meth) acrylate type, phenoxy-polyethylene glycol (meth) such as phenoxy-diethylene glycol (meth)acrylate, phenoxy-triethylene glycol (meth)acrylate, etc. Acrylate type, 2-ethylhexyl-polyethylene glycol (meth)acrylate, nonylphenyl-polyethylene glycol (meth)acrylate type, methoxy-dipropylene glycol (meth)acrylate Methoxy-polypropylene glycol (meth)acrylate type etc.

In addition, other monomer components other than the aforementioned (meth)acrylic acid alkylene oxide can also be used as the aforementioned monomer components. Specific examples of other monomer components include methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, secondary butyl (meth)acrylate, and tributyl (meth)acrylate. Grade butyl ester, isobutyl (meth)acrylate, hexyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate , N-nonyl (meth)acrylate, isononyl (meth)acrylate, n-decyl (meth)acrylate, isodecyl (meth)acrylate, n-dodecyl (meth)acrylate, ( Acrylate and/or methacrylate having an alkyl group with 1 to 14 carbon atoms, such as n-tridecyl meth)acrylate and n-tetradecyl (meth)acrylate.

In addition, carboxyl group-containing (meth)acrylates, phosphoric acid group-containing (meth)acrylates, cyano group-containing (meth)acrylates, vinyl esters, aromatic vinyl compounds, and acid anhydrides can also be suitably used. (Meth)acrylate, hydroxyl-containing (meth)acrylate, amino-containing (meth)acrylate, amino-containing (meth)acrylate, epoxy-containing (meth)acrylate ) Acrylates, N-acrylomorpholine, vinyl ethers, etc. are used as monomer components other than the aforementioned (meth)acrylate alkylene oxide.

As a preferred aspect, the aforementioned polyoxyalkylene chain compound containing no organopolysiloxane is a compound having at least a part of (poly)oxirane chain. By blending the aforementioned (poly)oxyethylene chain-containing compound, the compatibility with the base polymer can be improved, the exudation to the adherend can be well suppressed, and a low-polluting adhesive composition can be obtained. Among them, especially when a block copolymer of PPG-PEG-PPG is used, an adhesive with excellent low pollution properties can be obtained. As the aforementioned polyoxyethylene chain-containing compound, the (poly)oxyethylene chain accounts for 5 to 90% by weight of the weight of the aforementioned polyoxyalkylene chain-containing compound without organopolysiloxane, preferably It is 5 to 85% by weight, more preferably 5 to 80% by weight, and most preferably 5 to 75% by weight.

In addition, the commercially available products of the aforementioned polyoxyalkylene chain compound containing no organopolysiloxane include, for example, Adeka Pluonic 17R-4, Adeka Pluonic 25R-2 (all made by ADEKA); Latemul PD-420 , Latemul PD-420, Latemul PD-450, Emulgen 120 (manufactured by Kao); Aqualon HS-10, KH-10, Noigen EA-87, EA-137, EA-157, EA-167, EA-177 (above It is manufactured by Daiichi Industrial Pharmaceutical Co., Ltd.) and so on.

The content of the aforementioned oxygen-containing alkylene compound is preferably 0.01 to 5.0 parts by weight relative to 100 parts by weight of the adhesive polymer (main polymer, such as (meth)acrylic polymer) constituting the aforementioned adhesive composition , And it is preferably 0.02 to 2 parts by weight, more preferably 0.03 to 1.6 parts by weight, and most preferably 0.1 to 0.8 parts by weight. If it is in the aforementioned range, the light releasability (re-peelability) of the adhesive layer (surface protective film) used in the present invention can be easily exhibited, which is preferable.

<Crosslinking agent> In the surface protection film of the present invention, the aforementioned adhesive composition preferably contains a crosslinking agent. Furthermore, in the present invention, the aforementioned adhesive composition can be used to form an adhesive layer. For example, when the adhesive composition is an acrylic adhesive containing the (meth)acrylic polymer, by appropriately adjusting the constituent units, composition ratio, and crosslinking agent of the (meth)acrylic polymer Cross-linking by selecting and adding ratio, etc., can obtain an adhesive layer (surface protective film) with more excellent heat resistance.

As the crosslinking agent used in the present invention, isocyanate compounds, epoxy compounds, melamine-based resins, aziridine derivatives, metal chelate compounds, etc. can be used. In particular, isocyanate compounds or epoxy compounds are preferred. Moreover, these compounds may be used individually, and 2 or more types may be mixed and used for it.

二

三酮鍵等將前述異氰酸酯化合物進行改質所得之聚異氰酸酯改質體。市售品可列舉例如商品名Takenate 300S、Takenate 500、Takenate 600、Takenate D165N、Takenate D178N(以上為武田藥品工業公司製)；Sumidur T80、Sumidur L、Desmodur N3400 (以上為住化Bayer Urethane公司製)；Millionate MR、Millionate MT、Coronate L、Coronate HL、Coronate HX(以上為日本聚胺甲酸乙酯工業公司製)等。該等異氰酸酯化合物可單獨使用，亦可混合2種以上使用，亦可將雙官能之異氰酸酯化合物與三官能以上之異氰酸酯化合物併用來使用。藉由併用交聯劑來使用可使黏著性與耐反彈性(對於曲面的接著性)並存，而可獲得接著信耐性更優異的黏著劑層(表面保護薄膜)。Examples of the aforementioned isocyanate compounds include aliphatic polyisocyanates such as trimethylene diisocyanate, butylene diisocyanate, hexamethylene diisocyanate (HDI), and diisocyanate; Diisocyanate, cyclohexyl diisocyanate, isophorone diisocyanate (IPDI), 1,3-bis(isocyanatomethyl)cyclohexane and other alicyclic isocyanates; 2,4-toluene diisocyanate , 4,4'-Diphenylmethane diisocyanate, XDI and other aromatic isocyanates; through allophanate bond, biuret bond, trimeric isocyanate bond, uretdione bond, urea Bond, carbodiimide bond, uretonimine bond and

two

A polyisocyanate modified body obtained by modifying the aforementioned isocyanate compound with a three-ketone bond. Commercial products include, for example, the trade names Takenate 300S, Takenate 500, Takenate 600, Takenate D165N, Takenate D178N (the above are manufactured by Takeda Pharmaceutical Co., Ltd.); Sumidur T80, Sumidur L, and Desmodur N3400 (the above are manufactured by Sumika Bayer Urethane) ; Millionate MR, Millionate MT, Coronate L, Coronate HL, Coronate HX (the above are made by Japan Polyurethane Industry Co.), etc. These isocyanate compounds may be used alone, or two or more of them may be mixed for use, or a difunctional isocyanate compound and a trifunctional or higher isocyanate compound may be used together. By using a crosslinking agent in combination, adhesiveness and repulsion resistance (adhesion to curved surfaces) can be coexisted, and an adhesive layer (surface protective film) with more excellent adhesion resistance can be obtained.

Examples of the aforementioned epoxy compound include N,N,N',N'-tetraepoxypropyl-stubble diamine (trade name TETRAD-X, manufactured by Mitsubishi Gas Chemical Co., Ltd.) or 1,3-bis(N,N -Diglycidylaminomethyl) cyclohexane (trade name TETRAD-C, manufactured by Mitsubishi Gas Chemical Co., Ltd.) and the like.

Examples of the melamine-based resin include hexamethylol melamine and the like. Examples of the aziridine derivatives include HDU, TAZM, TAZO (manufactured by Hutong Pharmaceutical Co., Ltd.) and the like, which are commercially available products.

In the aforementioned metal chelate compound, aluminum, iron, tin, titanium, nickel, etc. can be mentioned as the metal component, and acetylene, methyl acetylacetate, ethyl lactate, etc. can be mentioned as the chelate component.

The content of the crosslinking agent used in the present invention is preferably 0.01-20 parts by weight, more preferably 0.1-15 parts by weight, and more preferably 0.5-10 parts by weight relative to 100 parts by weight of the aforementioned (meth)acrylic polymer. Parts, most preferably 1~8 parts by weight. When the aforementioned content is less than 0.01 parts by weight, the formation of cross-linking by the cross-linking agent may not be sufficient, resulting in a decrease in the cohesive force of the obtained adhesive layer, and insufficient heat resistance may not be obtained. The tendency of the cause of residual glue. On the other hand, when the content exceeds 20 parts by weight, the cohesive force of the polymer will increase and the fluidity will decrease, and the wetting of the attached body (such as the polarizing plate) will be insufficient, which may cause the adhesion between the attached body and the adhesive. The tendency to cause swelling between layers (adhesive composition layers). Moreover, these crosslinking agents may be used individually, and 2 or more types may be mixed and used for it.

<Cross-linking catalyst> The aforementioned adhesive composition may contain a cross-linking catalyst for making any of the above-mentioned cross-linking reactions more effectively proceed. The crosslinking catalyst can use tin-based catalysts such as dibutyl tin dilaurate, dioctyl tin dilaurate, etc.; ginseng (acetone) iron, ginseng (hexa-2,4-diketone) iron, Ginseng (heptane-2,4-dione) iron, ginseng (heptan-3,5-dione) iron, ginseng (5-methylhexa-2,4-dione) iron, ginseng (oct-2,4 -Diketone) iron, ginseng (6-methylheptan-2,4-dione) iron, ginseng (2,6-dimethylheptan-3,5-dione) iron, ginseng (non-2,4 -Diketone) iron, ginseng (non-4,6-dione) iron, ginseng (2,2,6,6-tetramethylheptan-3,5-dione) iron, ginseng (tridecane-6) ,8-diketone) iron, ginseng (1-phenylbutan-1,3-dione) iron, ginseng (hexafluoroacetone) iron, ginseng (ethyl acetate) iron, ginseng (acetate acetic acid) -N-propyl ester) iron, ginseng (acetate isopropyl ester) iron, ginseng (acetate-n-butyl ester) iron, ginseng (acetate-second butyl ester) iron, ginseng (acetate-tri Grade butyl ester) iron, ginseng (methyl acrylate) iron, ginseng (ethyl acrylate) iron, ginseng (acetate-n-propyl) iron, ginseng (isopropyl acrylate) iron, ginseng (Acrylic acetic acid-n-butyl ester) iron, ginseng (acrylic acid-secondary butyl ester) iron, ginseng (acrylic acid-tertiary butyl ester) iron, ginseng (acetate benzyl acetate) iron, ginseng (propyl acetate) Dimethyl diacid) iron, ginseng (diethyl malonate) iron, trimethoxy iron, triethoxy iron, triisopropoxy iron, iron (III) chloride and other iron-based catalysts. One type of these catalysts may be used, or two or more types may be used in combination.

The content of the aforementioned crosslinking catalyst is not particularly limited, but for example, relative to 100 parts by weight of the aforementioned (meth)acrylic polymer, it is preferably about 0.0001 to 1 part by weight, more preferably 0.001 to 0.5 part by weight. If it is within the aforementioned range, the speed of the crosslinking reaction when the adhesive layer is formed is high, and the usable life of the adhesive composition becomes longer, which is a preferred aspect.

In addition, the aforementioned adhesive composition may also contain other well-known additives, such as powders such as slip agents, colorants, and pigments; plasticizers, adhesive imparting agents, low molecular weight polymers, etc., according to the intended use. Surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, ultraviolet absorbers, polymerization inhibitors, silane coupling agents, antistatic agents, inorganic or organic fillers, metal powders, particles, foils, etc. .

<Surface protection film for optics with a separator> The surface protection film for optics (surface protection film) with a separator of the present invention is formed by forming the aforementioned adhesive layer on at least one side of the base film. In this case, Generally, the cross-linking of the adhesive composition is performed after the adhesive composition is applied, but the adhesive layer composed of the cross-linked adhesive composition can also be transferred to a substrate film or the like.

In addition, the method of forming the adhesive layer on the substrate film is not particularly limited. For example, the adhesive composition (solution) can be applied to the substrate film and the polymerization solvent is dried to remove it. It is made by forming an adhesive layer on the film. Thereafter, curing may be performed for the adjustment of the transfer of the components of the adhesive layer or the adjustment of the crosslinking reaction. In addition, when the adhesive composition is coated on the base film to produce a surface protective film, one or more solvents other than the polymerization solvent may be newly added to the adhesive composition to make it uniformly coated On the substrate film.

In addition, as a method for forming the adhesive layer when manufacturing the surface protection film of the present invention, a well-known method for manufacturing adhesive tapes can be used. Specifically, examples thereof include roll coating, gravure coating, reverse roll coating, roll brushing, spray coating, air knife coating, and extrusion coating using a die coater.

In the surface protection film of the present invention, the thickness of the aforementioned adhesive layer is usually 3-100 μm , and it is better to make it about 5-50 μm. If the thickness of the adhesive layer is within the aforementioned range, an appropriate balance of re-peelability and adhesiveness can be easily achieved, which is preferable.

In addition, the total thickness of the surface protection film of the present invention is preferably 8 to 300 μm , more preferably 10 to 200 μm , and most preferably 20 to 100 μm . If it is in the aforementioned range, the adhesive properties (repeelability, adhesiveness, etc.), workability, and appearance properties are excellent, which is a preferred aspect. In addition, the aforementioned total thickness refers to the total thickness of all layers including the base film, the adhesive layer, the separator, and other layers.

<Separated Piece>

The surface protection film of the present invention has an adhesive layer on at least one side of the substrate film, and has a separator on the opposite surface of the adhesive layer that is in contact with the substrate film; the characteristics of the surface protection film are : The aforementioned separator has a release layer and a polyester-based substrate, the aforementioned polyester-based substrate has holes, the thickness of the aforementioned polyester-based substrate is 25 to 100 μm , and the aforementioned separator is 180° to the adhesive layer. °The initial peel force is below 0.7N/50mm. In order to protect the adhesive surface of the adhesive layer, the aforementioned separator is attached to the surface of the adhesive layer. Especially because it has a specific thickness and has holes, the stiffness (rigidity) of the separator itself can be suppressed to be low, so that When the separator is peeled from the surface of the adhesive layer, it has excellent releasability and workability, and cushioning properties can be provided by the holes, so that it can prevent the adhesive dents that may be generated after the adhesive is applied, which is a preferred aspect.

<Polyester-based substrate> The aforementioned polyester-based substrate (sometimes simply referred to as "substrate") is not particularly limited as long as it is a polyester-based film that can protect the adhesive layer and has pores, and examples thereof include Polyethylene terephthalate film, polyethylene naphthalate, polybutylene terephthalate, etc.

The thickness of the aforementioned polyester-based substrate is 25-100 μm, preferably 30-80 μm, and preferably 40-70 μm. If it is in the aforementioned range, the workability of sticking to the adhesive layer and the releasability or workability of the adhesive layer are excellent, and therefore it is preferable. In addition, if the thickness of the base material is greater than 100 μm, the stiffness (rigidity) of the separator itself will increase, and the peelability or workability will be poor.

The aforementioned polyester-based substrate can be subjected to various surface treatments such as corona discharge treatment, or various surface treatments such as embossing, as required. It can also be blended with fillers (inorganic fillers, organic fillers, etc.), anti-aging agents, antioxidants, ultraviolet absorbers, antistatic agents, slip agents, plasticizers, colorants (pigments, dyes, etc.), etc. Various additives.

Relative to the volume of the aforementioned polyester-based substrate, the porosity of the polyester-based substrate is preferably 15% (vol%) or more, preferably 18% or more, and more preferably 20% or more. With a porosity of 15% or more, the cushioning properties of the separator can be improved, and the fillers (such as polyterephthalene) contained in the base film constituting the optical surface protection film or the polyester base material constituting the separator can be absorbed. Concave and convex caused by ethylene formate (PET) filler, and can suppress the generation of adhesion dents caused by separation parts, etc. In addition, since the stiffness (rigidity) of the separator is low, the peelability of the separator can be improved. In addition, from the viewpoint of the strength of the separator, etc., the porosity is preferably 40% or less, and more preferably 30% or less.

The shape of the pores of the aforementioned polyester-based base material is spherical, elliptical, or thin line-like, and it is preferable to adopt a dispersed form. The aforementioned dispersion diameter is preferably 0.01-100 μm, preferably 0.05-30 μm. If it is in the aforementioned range, it has the strength of the separator, excellent cushioning properties, and the peelability of the separator, which is a preferred aspect. In addition, the shape of the aforementioned hole can be observed by observing the cross section of the substrate with a scanning electron microscope.

<The mold release layer> The mold release layer has adhesiveness to the polyester-based base material and releasability to the adhesive layer, and may be formed of a mold release agent composition. The aforementioned release agent composition is not particularly limited. Polysiloxane compounds such as dimethylsiloxane or diphenylsiloxane; long-chain alkyl groups such as polysiloxane resin, fluororesin, ASHIO RESIN, etc. can be used. Department of compounds and so on.

In addition, the aforementioned release agent composition may also contain other well-known additives, for example, powders such as antistatic agents, colorants, and pigments can be appropriately added according to the intended use; surfactants, plasticizers, and adhesion-imparting agents , Low molecular weight polymers, surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, ultraviolet absorbers, polymerization inhibitors, silane coupling agents, inorganic or organic fillers, metal powders, particles, etc.

<Production of the separator> The separator is formed by using the release agent composition on the polyester base material.

The method of forming a release layer on the aforementioned polyester-based substrate is not particularly limited. For example, it can be formed on the substrate by applying a solution of the aforementioned release agent composition to the substrate and drying and removing the polymerization solvent. The release layer is made. After that, it is also possible to perform curing for the adjustment of the transfer of the components of the release layer, etc. In addition, when the release agent composition is applied to the substrate to produce a release layer, one or more solvents other than the polymerization solvent may be newly added to the release agent composition to enable uniform coating On the substrate.

In addition, as the method for forming the aforementioned release layer, a well-known method for producing the release layer can be used. Specifically, examples thereof include roll coating, gravure coating, reverse roll coating, roll brushing, spray coating, air knife coating, and extrusion coating using a die coater.

The thickness of the aforementioned release layer is typically 1 to 200 nm, preferably 5 to 100 nm, and more preferably 10 to 50 nm. If the thickness of the release layer is too small, the release effect of the release layer is weak and it is difficult to peel the separator. Therefore, it may be difficult to perform the work of bonding the optical surface protection film. On the other hand, if it is too thick, it may affect the contamination of the adhesive layer of the optical surface protection film.

Examples of commercially available products of the aforementioned separator include Crisper K7211-50 μm, Crisper K7211-38 μm (manufactured by Toyobo Co., Ltd. above); PET50 (K2411) PAT1 8LK, PET50 (K2411) PAT1 9K (manufactured by Lintec Co., Ltd. above) and the like.

<Lamination of optical surface protection film and separator> The form of the optical surface protection film with a separator of the present invention is to bond the release layer of the separator on the surface of the adhesive layer of the optical surface protection film. become. The pasting industry can use well-known manufacturing methods.

<Optical member> In the present invention, the surface protective film for optics after peeling off the surface of the adhesive layer of the above-mentioned separator-attached optical surface protection film can be attached to the optical member to protect the optical member. The aforementioned separator has excellent cushioning properties so that it is not easy to produce dents and has good peelability. Also, the aforementioned optical surface protection film has excellent appearance grade (appearance), so it can be used for surface protection during processing, transportation, and shipping. Use (surface protection film), and is useful for protecting the surface of the aforementioned optical member (polarizing plate, etc.). Example

The following describes several embodiments related to the present invention, but it is not intended to limit the present invention to those shown in related specific examples. In addition, "parts" and "%" in the following description are based on weight unless otherwise specified. And the blending amount (addition amount) has been shown in the table.

In addition, each characteristic in the following description was measured or evaluated as follows, respectively.

<Measurement of the porosity of the polyester-based substrate constituting the separator> After taking a cross-sectional photograph of the polyester-based substrate with a scanning electron microscope, the pores in the cross-sectional area are drawn on the tracing film, and the entire surface is painted. After performing image processing with an image analysis device, the porosity (%) is calculated as the area ratio, and the value is directly expressed as the porosity (vol%).・Scanning electron microscope used: S-510 scanning electron microscope manufactured by Hitachi, Ltd. ・Image analysis device used: Luzex IID manufactured by Nireco Co., Ltd.

<Measurement of the thickness of the separator> The thickness of the separator (the thickness of the separator) is the total thickness of the polyester-based base material and the release layer, and is measured using R1-205 manufactured by Ozaki Manufacturing Co., Ltd.

<Measurement of the glass transition temperature (Tg) of (meth)acrylic polymers> The glass transition temperature Tg (℃) is the value of the following literature as the glass transition temperature Tgn (℃) of the homopolymer formed from each monomer , And calculated by the following formula. Formula: 1/(Tg+273)=Σ[Wn/(Tgn+273)] (where Tg(℃) represents the glass transition temperature of the copolymer, Wn(-) represents the weight fraction of each monomer, Tgn (°C) represents the glass transition temperature of the homopolymer of each monomer, n represents the type of each monomer). Literature value: 2-Ethylhexyl acrylate (2EHA): -70℃ Butyl acrylate (BA): -55℃ 2-Hydroxyethyl acrylate (HEA): -15℃ Acrylic acid (AA): 106℃ In addition, literature The value is based on the "Synthesis, Design and New Use Development of Acrylic Resin" (published by the Publishing Department of the Central Management Development Center).

<Measurement of the weight average molecular weight (Mw) of the (meth)acrylic polymer> The weight average molecular weight (Mw) of the (meth)acrylic polymer used uses the GPC device (HLC- 8220GPC) for measurement. The measurement conditions are as follows: Sample concentration: 0.2% by weight (THF solution) Sample injection volume: 10μl Eluent: THF Flow rate: 0.6ml/min Measurement temperature: 40℃ Column: Sample column: TSKguardcolumn SuperHZ-H (1 piece)+ TSKgel SuperHZM-H (2 units) Reference column: TSKgel SuperH-RC (1 unit) Detector: Differential Refractometer (RI) In addition, the weight average molecular weight is calculated in terms of polystyrene.

<Whether there are dents on the surface of the adhesive layer> Under a fluorescent lamp in a darkroom, the separator is peeled off from the surface of the adhesive layer of the optical surface protection film, and light is reflected on the surface of the adhesive layer, and the presence or absence of dents is visually confirmed mark. When there is no dent, it is marked as ○, and when there is a dent, it is marked as ×.

<Measurement of the initial peel force of the separator> As shown in Figure 2, the optical surface protection film 3 with the separator is cut into a size of 50 mm in width and 100 mm in length, and a double-sided tape 4 (Nitto Denko The base film 22 of the optical surface protective film 3 with a separator is pressed onto the glass 5 (S9213, manufactured by Songnang Glass Industry Co., Ltd.) made by the company, No. 500, at a pressure of 0.25 MPa and a speed of 0.3 m/min. s surface. Then, the single-sided adhesive tape 6 (No. 720, manufactured by Nitto Denko Co., Ltd., width 50 mm) was cut into a length of 50 mm. The adhesive surface of the single-sided adhesive tape 6 was pressed onto the separator 1 with a width of 50 mm of the optical surface protective film 3 attached to the separator with a manual roll, so that the end thereof exceeded 1 mm. Leave it at 23°C and 50%RH for 10 seconds. After that, use a universal testing machine to peel off the single-sided adhesive tape 6 at a speed of 0.3 m/min in the 180° direction, and use the maximum stress applied at the beginning of peeling during peeling as the initial peeling force (N/50mm).

The aforementioned initial peeling force (peeling force) is 0.7N/50mm or less, preferably 0.68N/50mm or less, and preferably 0.65N/50mm or less. If the aforementioned initial peeling force is greater than 0.7N/50mm, when using a thick separator, it takes time to peel the separator from the surface of the adhesive layer of the optical surface protection film, so the peelability and workability are poor. On the other hand, if the initial peeling force is too low, it may not fully protect the surface of the adhesive layer of the optical surface protection film, so it is preferably 0.2N/50mm or more.

<Preparation of (meth)acrylic polymer (A)> 100 parts by weight of 2-ethylhexyl acrylate (2EHA) and 4 parts by weight of 2-hydroxyethyl acrylate (HEA) were used as polymerization initiator 2 , 0.2 parts by weight of 2'-azobisisobutyronitrile (AIBN) and 205 parts by weight of ethyl acetate were fed into a 4-necked flask equipped with a stirring blade, thermometer, nitrogen introduction tube, and cooler, and nitrogen was introduced while stirring slowly , The liquid temperature in the flask was maintained at around 63°C and the polymerization reaction was carried out for about 4 hours to prepare a (meth)acrylic polymer (A) solution (about 35% by weight). The aforementioned (meth)acrylic polymer (A) has a weight average molecular weight of 650,000 and a Tg of -68°C.

<Preparation of (meth)acrylic polymer (B)> 95 parts by weight of butyl acrylate (BA), 5 parts by weight of acrylic acid (AA), and 2,2'-azobisisobutyl as a polymerization initiator 0.1 part by weight of nitrile and 234 parts by weight of ethyl acetate were fed into a 4-necked flask equipped with a stirring blade, a thermometer, a nitrogen inlet tube, and a cooler. Nitrogen was introduced while stirring slowly, and the liquid temperature in the flask was maintained at around 65°C. The polymerization reaction was carried out for 6 hours to prepare a (meth)acrylic polymer (B) solution (30% by weight). The weight average molecular weight (Mw) of the aforementioned (meth)acrylic polymer (B) was 1.1 million, and the glass transition temperature (Tg) was -47°C.

[Preparation of Acrylic Adhesive (1) Solution] The above-mentioned (meth)acrylic polymer (A) solution (35% by weight) was diluted with ethyl acetate to 29% by weight, and 500 parts by weight of the solution (solid (Component 100 parts by weight), a tri-functional isocyanate compound as a crosslinking agent, a trimer isocyanate of hexamethylene diisocyanate (Coronate HX: C/HX, manufactured by Japan Polyurethane Co.) 4 weight Parts (solid content 4 parts by weight), after 1.5 parts by weight (solid content 0.015 parts by weight) of dibutyl tin dilaurate ("Sn" in Table 2, 1% by weight ethyl acetate solution) as a crosslinking catalyst, It is maintained at around 25°C and mixed and stirred for about 1 minute to prepare an acrylic adhesive (1) solution.

[Preparation of acrylic adhesive (2) solution] The above-mentioned (meth)acrylic polymer (B) solution (30% by weight) was diluted with ethyl acetate to 29% by weight, and 500 parts by weight of the solution (solid 100 parts by weight of ingredients), add epoxy-based crosslinking agent (1,3-bis(N,N-diglycidylaminomethyl)cyclohexane, epoxy equivalent: 110, Number of functional groups: 4. Trade name "TETRAD-C": T/C, manufactured by Mitsubishi Gas Chemical Corporation) 6 parts by weight (6 parts by weight of solid content), then mixed and stirred to prepare an acrylic adhesive (2) solution .

[Preparation of acrylic adhesive (3) solution] The (meth)acrylic polymer (A) solution (35% by weight) was diluted with ethyl acetate to 29% by weight, and 500 parts by weight of the solution (solid 100 parts by weight of ingredients), add an isocyanate-based crosslinking agent (hexamethylene diisocyanate trimeric isocyanate body (trade name "Coronate HX": C/HX, Japanese polyurethane) Company made) 5 parts by weight (5 parts by weight of solid content), 3 parts by weight of dibutyltin dilaurate (1% by weight ethyl acetate solution) as a crosslinking catalyst (0.03 parts by weight of solid content), no additives After 0.3 parts by weight (0.3 parts by solid content) of organopolysiloxane containing polyoxyalkylene chain compound (Aqualon HS-10, manufactured by Daiichi Industrial Pharmaceutical Co., Ltd.), it was mixed and stirred to prepare an acrylic adhesive (3) Solution.

<Example 1> [Production of antistatic treatment film] 10 parts by weight of antistatic agent (manufactured by Solvex, Micro-Solver RMd-142, mainly composed of tin oxide and polyester resin), and 30 parts by weight of water It is diluted with a mixed solvent composed of 70 parts by weight of methanol to prepare an antistatic agent solution. Use a meyer bar to coat the prepared antistatic agent solution on the base film of a polyethylene terephthalate (PET) film (thickness: 38μm), then dry at 130°C for 1 minute to remove The solvent forms an antistatic layer (thickness: 0.2 μm) to form an antistatic treatment film.

[Production of optical surface protective film with separate parts] Coat the above-mentioned acrylic adhesive (1) solution on the surface opposite to the anti-static treatment surface of the above-mentioned anti-static treatment film, and heat it at 130°C for 2 minutes. An adhesive layer with a thickness of 15 μm is formed. Next, separate Crisper K7211-50μm (manufactured by Toyobo Co., Ltd., specific gravity of polyester-based substrate: 1.1g/cm ³ , porosity of polyester-based substrate: 20%, thickness of 50μm). ) The polysiloxane-treated surface is attached to the surface of the adhesive layer to form an optical surface protection film with separate parts.

<Examples 2 to 5, Comparative Examples 1 to 4> As shown in Table 2, the acrylic adhesive (1) solution used in Example 1 was used, or instead of it, an acrylic adhesive (2) solution or acrylic was used The adhesive (3) solution was used, and the separator described in Table 3 was used, and the optical surface protective film with the separator was produced in the same manner as in Example 1.

Regarding the optical surface protection films with separate parts of the Examples and Comparative Examples, the contents of the above blending, various measurements and evaluation results performed are shown in Tables 1 to 3. In addition, the blending amount in the table represents the effective ingredient.

[Table 1]

[Table 2]

[table 3]

From Table 3 above, it can be confirmed that all the examples have excellent peelability and workability by setting the porosity and thickness of the polyester base material constituting the separator within the desired range, and can prevent the generation of sink marks. . In addition, since no dents are formed on the surface of the adhesive layer in the examples, air bubbles will not be entrained when it is attached to the attached body. However, when the optical surface protection film is attached to the attached body for inspection, Can provide optical surface protection film with excellent inspection properties. On the other hand, it was confirmed that in Comparative Examples 1 to 3, since the porosity of the polyester-based substrate constituting the separator is not in the expected range, the separator has strong stiffness (rigidity), but poor peelability and workability; Comparative Example 4 It was confirmed that because the thickness of the polyester-based substrate was not in the expected range, it was unable to exhibit cushioning properties, resulting in dents caused by separation parts.

Industrial Applicability The optical surface protection film with separate parts disclosed here is suitable for manufacturing and transporting as a component of liquid crystal display panels, plasma display panels (PDP), organic electroluminescence (EL) displays, etc. When the used optical member is used, it is used as a surface protection film for protecting the optical member. It is particularly useful as an optical surface protection film for optical components such as polarizing plates (polarizing films), wave plates, retardation plates, optical compensation films, brightness enhancement films, light diffusion sheets, and reflective sheets for liquid crystal display panels.

1‧‧‧Separation piece 2.‧‧‧Optical surface protection film 3‧‧‧Optical surface protection film with separation piece 4.‧‧‧Double-sided adhesive tape ‧‧‧Polyester-based substrate 12‧‧‧Release layer 21‧‧‧Adhesive layer 22‧‧‧Substrate film

Fig. 1 is a schematic cross-sectional view showing a configuration example of a surface protective film for optics with a separator of the present invention. Fig. 2 is a schematic cross-sectional view showing a configuration example when the separator is peeled off from the optical surface protective film with separator of the present invention.

Claims (4)

A surface protective film for optics with a separator, which has a surface protective film for optics and a separator. The surface protective film for optics has an adhesive layer on at least one side of a substrate film, and the separator is located in the aforementioned adhesive The surface of the layer in contact with the base film is the opposite side; the optical surface protection film with a separator is characterized in that the separator has a mold release layer and a polyester-based substrate, and the polyester-based substrate has For the holes, the thickness of the polyester base material is 25-100 μm, and the 180° initial peeling force of the separator to the adhesive layer is less than 0.7N/50mm. According to claim 1, the optical surface protection film with a separator, wherein the porosity of the polyester-based substrate is 15% or more relative to the volume of the aforementioned polyester-based substrate. According to claim 1 or 2, the optical surface protection film with separate parts, wherein the aforementioned base film is a polyester film. The optical surface protection film with a separator according to claim 1, wherein the adhesive layer is formed of an adhesive composition containing a (meth)acrylic polymer.

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