JP5130768B2 - Protective film for optical member, method for producing protective film for optical member, and protective film raw material for optical member - Google Patents

Description

  The present invention relates to an optical member protective film used for protecting an optical member from scratches and dirt.

  The protective film for an optical member usually has a transparent substrate and a pressure-sensitive adhesive layer formed on the transparent substrate, and the pressure-sensitive adhesive layer of the protective film for the optical member is adhered to the optical member. Therefore, it is used for the purpose of preventing bonding, scratching of the optical member, contamination, and the like. For example, until the optical member such as a polarizing plate and a retardation plate is laminated to form a liquid crystal display device, the optical member is covered with a protective film for the optical member, whereby a distribution process or a manufacturing process of the liquid crystal display device is performed. It is used for the purpose of preventing surface damage and protecting from contamination. And the optical member is laminated | stacked, it is set as a liquid crystal display device, and the protection film for optical members is peeled and removed in the stage where protection of the surface became unnecessary.

  By the way, it is known that such protective films for optical members generate static electricity when they are peeled off from the optical members. When static electricity is generated, dust and the like that are present in the vicinity are attracted, causing adhesion to the surface of the optical member and resulting decrease in yield. Therefore, the protective film for optical members usually prevents the generation of static electricity. For example, an antistatic layer is formed (Patent Document 1).

  Here, it is preferable that the antistatic layer is formed at a position close to the optical member to be protected. This is because the function of preventing the attracting of dust and the like and the function of preventing adhesion can be effectively exhibited by disposing the optical member close to the optical member to be protected. However, when the antistatic layer is formed by applying an antistatic agent-containing liquid having an antistatic agent on the surface of the protective film for optical members that is in direct contact with the optical member, that is, on the pressure-sensitive adhesive layer. The pressure-sensitive adhesive layer cannot exhibit adhesiveness, and there is a problem in that the adhesion between the protective film for optical members and the optical member is remarkably lowered. Further, there has been a problem that stick-slip, which is a phenomenon in which the optical member protective film is repeatedly wound and slipped on the way from the state in which the protective film for the optical member is wound in a roll shape, is generated. When such stick-slip occurs, horizontal stripes in the direction perpendicular to the unwinding direction are formed on the protective film for optical members, and the surface of the optical member is bonded to the protective film for optical members. There were problems such as making optical inspection difficult.

JP 2002-355919 A

  The present invention has been made in view of the above problems, and provides an optical member protective film having excellent antistatic properties, good stick-slip properties, and excellent adhesion to optical members. The main purpose is to do.

  In order to solve the above problems, the present invention provides a transparent base material, a cross-linking agent formed on one surface of the transparent base material, an adhesive, an epoxy-based cross-linking agent or an isocyanate-based cross-linking agent, and a metal chelating agent. A pressure-sensitive adhesive layer containing a pressure-sensitive adhesive layer-forming material, a transition part formed on the pressure-sensitive adhesive layer and made of an anti-static agent layer-forming material containing an antistatic agent, and the pressure-sensitive adhesive layer of the transparent substrate. A protective film for an optical member, comprising a surface layer made of the antistatic agent-forming material and formed on the other surface that is not formed.

According to the present invention, when the transition portion is formed on the pressure-sensitive adhesive layer, when the protective film for an optical member is bonded to an optical member to be protected, the transition portion is It can be in the state which touches the surface of an optical member directly. For this reason, the charge at the time of peeling from the optical member can be effectively prevented, and the attraction and adhesion of dust and the like can be effectively prevented.
In addition, since the transition portion is formed on the pressure-sensitive adhesive layer, the adhesiveness is appropriately adjusted, so that the stick for unwinding the protective film for optical members from a rolled state is used. The slip property can be made good.

  In this invention, it is preferable that the adhesive force of the said protective film for optical members is 0.01N / 25mm-0.49N / 25mm. This is because when the adhesive force of the protective film for optical members is within the above range, the stick-slip property can be further improved. Further, it is possible to adhere to the optical member to be protected with sufficient strength and to easily peel off the optical member when it becomes unnecessary.

  In the present invention, the pressure-sensitive adhesive is preferably an acrylic pressure-sensitive adhesive. This is because when the pressure-sensitive adhesive is an acrylic pressure-sensitive adhesive, the pressure-sensitive adhesive layer can be made excellent in transparency and durability, and is suitable for use as an optical member.

  The present invention includes a transparent substrate, an adhesive layer formed on one surface of the transparent substrate, a transition portion formed on the adhesive layer, and the adhesive layer of the transparent substrate. An antistatic agent layer comprising an antistatic agent on one surface of the transparent substrate, the surface layer being formed on the other surface that is not formed. An antistatic agent layer is formed by applying a forming material, an antistatic agent layer forming step, and an adhesive on the other surface of the transparent base material on which the antistatic agent layer is not formed, By applying a pressure-sensitive adhesive layer-forming material having an epoxy-based crosslinking agent or an isocyanate-based crosslinking agent and a metal chelating agent, a pressure-sensitive adhesive layer is formed, and the antistatic agent layer is formed on one surface. The optical part having the pressure-sensitive adhesive layer formed on the other surface A part of the antistatic agent layer is transferred onto the pressure-sensitive adhesive layer by winding the pressure-sensitive adhesive layer-forming step for forming the protective film laminate and the protective film laminate for the optical member into a roll. And forming a transition part made of the antistatic agent layer forming material on the pressure-sensitive adhesive layer by winding up the laminate for a protective film for an optical member wound up in the form of a roll. There is provided a method for producing a protective film for an optical member, comprising at least an unwinding step of forming a surface layer made of an antistatic agent layer forming material on a surface of a base material.

According to the present invention, by performing the transfer step described above, the pressure-sensitive adhesive layer and the antistatic agent layer are brought into close contact with each other, and a part of the antistatic agent layer is transferred onto the pressure-sensitive adhesive layer. The protective film for an optical member obtained after the unwinding step may have the transition portion formed on the pressure-sensitive adhesive layer. For this reason, the protective film for optical members finally obtained can be effectively prevented from being charged when being peeled from the optical member, and can be effectively prevented from attracting and adhering dust and the like. can do.
In addition, since the transition portion is formed on the pressure-sensitive adhesive layer, the adhesiveness is appropriately adjusted. Therefore, the protective film for an optical member produced by the production method of the present invention is rolled. It is possible to suppress the occurrence of stick-slip when unwinding from the state of being wound around, so that the stick-slip property can be improved. That is, in the unwinding step, it is possible to suppress the occurrence of stick slip, and it is possible to manufacture a protective film for an optical member that has no horizontal stripes.

  The present invention provides a protective film original fabric for an optical member, which is a roll of a protective film for an optical member wound in a roll shape, wherein the unwound film is the protective film for an optical member described above. To do.

  According to the present invention, the protective film for an optical member can be easily obtained by the film unwound from the protective film for the optical member wound into a roll being the protective film for an optical member described above. it can.

  According to this invention, it is preferable that the unwinding intensity | strength at the time of unwinding the said protective film for optical members is 0.29 N / 25mm or less from the said protective film original film for optical members. This is because when the unwinding strength is in the above range, unwinding failure such as unwinding can be prevented.

  The main object of the present invention is to provide a protective film for an optical member having excellent antistatic properties, good stick-slip properties, and excellent adhesiveness to the optical member.

  The present invention relates to a protective film for an optical member, a method for producing a protective film for an optical member, and an original film for a protective film for an optical member. Hereinafter, the protective film for optical members of the present invention, the method for producing the protective film for optical members, and the protective film original fabric for optical members will be described.

A. First, the protective film for optical members of the present invention will be described. The protective film for optical members of the present invention is formed on one surface of the transparent substrate and the transparent substrate, and has a pressure-sensitive adhesive, an epoxy-based crosslinking agent or an isocyanate-based crosslinking agent, and a metal chelating agent. A pressure-sensitive adhesive layer containing a pressure-sensitive adhesive layer-forming material, a transition part formed on the pressure-sensitive adhesive layer and made of an anti-static agent layer-forming material containing an antistatic agent, and the pressure-sensitive adhesive layer of the transparent substrate are formed. And a surface layer made of the antistatic agent-forming material.

  Such a protective film for an optical member of the present invention will be described with reference to the drawings. FIG. 1 is a schematic sectional view showing an example of the protective film for an optical member of the present invention. As illustrated in FIG. 1, the protective film 10 for an optical member of the present invention is formed on a transparent substrate 1 and one surface of the transparent substrate 1, and is an adhesive, an epoxy-based crosslinking agent, or an isocyanate-based crosslinking. Pressure-sensitive adhesive layer 2 including a pressure-sensitive adhesive layer-forming material having a crosslinking agent and a metal chelating agent, and an anti-static agent layer-forming material including an antistatic agent partially on the pressure-sensitive adhesive layer 2 And a transition layer 3 formed on the other surface of the transparent substrate 1 on which the pressure-sensitive adhesive layer 2 is not formed, and a surface layer 4 made of the antistatic agent-forming material. Is.

According to the present invention, when the transition portion is formed on the pressure-sensitive adhesive layer, when the protective film for an optical member is bonded to an optical member to be protected, the transition portion is It can be in the state which touches the surface of an optical member directly. For this reason, the charge at the time of peeling from the optical member can be effectively prevented, and the attraction and adhesion of dust and the like can be effectively prevented.
Further, conventionally, there has been a problem that stick slip, which is a phenomenon that cannot be continuously unwound, occurs when the protective film for an optical member is wound in a roll shape when it is unwound. When such stick-slip occurs, horizontal stripes in the direction perpendicular to the unwinding direction are formed on the protective film for optical members, and the surface of the optical member is bonded to the protective film for optical members. There were problems such as making optical inspection difficult. On the other hand, the protective film for optical members of the present invention can suppress the occurrence of stick-slip when the protective film for optical members is unwound from the rolled state, and has good stick-slip properties. It can be. Although it is not clear why the stick-slip property is improved as described above, the transition part is formed on the pressure-sensitive adhesive layer so that the antistatic agent layer-forming material is partially present, It is estimated that this is because the adhesiveness is appropriately adjusted.

  As described above, the optical functional film of the present invention has a transparent substrate, a transition portion, a surface layer, and an adhesive layer. Hereinafter, each structure of the protective film for optical members of such this invention is demonstrated.

1. Transition part The transition part used for this invention is formed on the adhesive layer mentioned later, and consists of an antistatic agent layer forming material.

(1) Antistatic agent layer forming material The antistatic agent layer forming material used in the present invention includes an antistatic agent, can exhibit desired antistatic properties, and has transparency. If it is, it will not specifically limit.
As such an antistatic agent layer forming material, a material containing an antistatic agent and a binder can be used.

The antistatic agent used in the present invention is not particularly limited as long as it has antistatic properties and transparency, and examples thereof include quaternary ammonium salts, pyridium salts, and primary grades. Cationic antistatic agent having a cationic group such as tertiary amino group; Anionic antistatic agent having anionic group such as sulfonate group, sulfate ester base, phosphate ester base; amino acid system, amino acid sulfate ester Surfactant type antistatic agents such as non-ionic antistatic agents such as amino alcohol type, glycerin type and polyethylene glycol type, and further monomer components containing the above surfactant type antistatic agents A polymeric surfactant type antistatic agent or the like having a high molecular weight can be used.
Further, antimony-doped indium tin oxide (ATO), indium tin oxide (ITO), organic compound fine particles surface-treated with gold and / or nickel, and the like can be used. Furthermore, conductive polymers such as polyacetylene, polypyrrole, polythiophene, polyaniline, polyphenylene vinylene, polyacene, or derivatives thereof can also be used.

  In the present invention, any of the above-mentioned antistatic agents can be suitably used, and among them, dilauryl diethoxyl type quaternary ammonium salt, dicetyl diethoxyl type quaternary ammonium salt, distearyl type 4th compound. Cationic antistatic agents having a quaternary ammonium salt such as a quaternary ammonium salt (for example, Colcoat NR-121X manufactured by Colcoat Co., Ltd.), polyaniline, polypyrrole, polyacetylene, polythiophene, poly (p-phenylene), poly (p- A conductive polymer such as phenylene vinylene (for example, Colcoat SP-2001 manufactured by Colcoat Co., Ltd.) can be preferably used, and in particular, dilauryl diethoxyl type quaternary ammonium salt, dicetyl diethoxyl type quaternary ammonium salt, Quaternary anions such as distearyl type quaternary ammonium salts Cationic antistatic agents having a salt, can be preferably used. It is because it is excellent in antistatic property and transparency.

When using a polymer-based antistatic agent such as a polymer-based surfactant type antistatic agent and a conductive polymer, the weight-average molecular weight of the polymer-based antistatic agent is in the range of 5,000 to 300,000. It is preferable that it is in the range of 50,000 to 200,000. It is because it becomes easy to form the said transition part because it is the said range. That is, as described in “B. Method for producing protective film for optical member” described later, the transition portion is formed of an antistatic agent layer containing the antistatic agent layer forming material on one side of a transparent substrate described later. This is because in the case where a part of the antistatic agent layer is formed on the pressure-sensitive adhesive layer, the antistatic agent layer can be easily transferred.
In addition, the said weight average molecular weight is a value of polystyrene conversion at the time of measuring by gel permeation chromatography (GPC).

  The content of the antistatic agent used in the present invention is not particularly limited as long as the desired antistatic property can be exhibited, and the use of the protective film for optical members of the present invention and the charging used. Although it differs depending on the type of the inhibitor, etc., it is preferably in the range of 4% by mass to 99% by mass in the antistatic agent layer forming material, and in particular, in the range of 10% by mass to 80% by mass. It is preferable to be within. This is because if it is less than the above range, sufficient antistatic properties cannot be exhibited, and if it exceeds the above range, there is no change in antistatic properties.

  The binder contained in the antistatic agent layer forming material used in the present invention is not particularly limited as long as it is a transparent resin that can stably hold the antistatic agent. For example, a thermoplastic resin A thermosetting resin, a photosensitive resin, or the like can be used.

  Examples of the thermoplastic resin include polyacrylic acid, polymethacrylic acid, polyacrylate, polymethacrylate, polyolefin, polystyrene, polyamide, polyimide, polyvinyl chloride, polyvinyl alcohol, polyvinyl butyral, polycarbonate, polyester, and polyurethane. .

  As the thermosetting resin, a monomer having a curing reactive functional group that can be cured by heating and proceeding with a large molecular weight reaction such as polymerization or crosslinking with the same functional group or another functional group, Oligomers and polymers can be used. Specifically, a monomer or oligomer having an alkoxy group, a hydroxyl group, a carboxyl group, an amino group, an epoxy group, a hydrogen bond forming group, or the like can be used.

  As the above-mentioned photosensitive resin, a monomer having a polymerizable functional group that causes a reaction that causes a large molecule such as polymerization or dimerization to proceed directly or indirectly by the action of an initiator when irradiated with light. Oligomers and polymers can be used with photoinitiators. In the present invention, a radical polymerizable compound having an ethylenically unsaturated bond such as an acrylic group, a vinyl group or an allyl group, or a photo cationic polymerizable compound such as an epoxy group-containing compound can be used. . Specifically, monofunctional monomers such as methyl (meth) acrylate, ethyl (meth) acrylate, ethylhexyl (meth) acrylate, styrene, methylstyrene, N-vinylpyrrolidone, and polyfunctional monomers such as polymethylolpropane tri (meta ) Acrylate, hexanediol (meth) acrylate, tripropylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, 1,6-hexanediol di (Meth) acrylate, neopentyl glycol di (meth) acrylate and the like can be mentioned.

  In the present invention, any of the above binders can be suitably used. Among them, polyacrylic acid, polymethacrylic acid, polyacrylate, polymethacrylate, polyolefin, polystyrene, polyamide, polyimide, polyvinyl chloride, polyvinyl alcohol, polyvinyl A thermoplastic resin such as butyral, polycarbonate, polyester, or polyurethane can be suitably used, and particularly polyester or polyacrylate can be suitably used. This is because the transparency is particularly excellent and the adhesion to the substrate is excellent.

The weight average molecular weight (Mw) of the binder used in the present invention is not particularly limited as long as it can stably hold the antistatic agent, but is 3,000 to 300,000. It is preferable to be within the range, and it is particularly preferable to be within the range of 5,000 to 100,000. This is because if it is smaller than the above range, it may be difficult to stably hold the antistatic agent. Moreover, it is because it may become difficult to form the said transition part if it is larger than the said range. That is, as described in “B. Method for producing protective film for optical member” described later, the transition portion includes the antistatic agent layer-forming material formed on one side of the transparent substrate described later. This is because in the case where the antistatic agent layer is formed by transferring a part of the antistatic agent layer onto the pressure-sensitive adhesive layer, it may be difficult to transfer the antistatic agent layer.
In addition, the said weight average molecular weight is a value of polystyrene conversion at the time of measuring by gel permeation chromatography (GPC).

  The antistatic agent layer forming material used in the present invention is not particularly limited as long as it contains the above antistatic agent, and other additives may be added depending on the use of the protective film for optical members of the present invention. An agent can be included.

  Examples of the other additive used in the present invention include a photopolymerization initiator for initiating photopolymerization when the binder is a photosensitive resin.

(2) Transition part The transition part used for this invention consists of the said antistatic agent layer forming material, and the adhesive layer mentioned later so that the protective film for optical members of this invention may exhibit adhesiveness It is formed above.
As such a transition part, for example, as shown in FIG. 1 which has already been described, a material in which the antistatic agent layer forming material partially exists on the pressure-sensitive adhesive layer 2 can be exemplified.

  The thickness of the transition part used in the present invention may not be clearly defined when the content of the material constituting the transition part is laminated so as to change continuously. It is preferably in the range of 01 μm to 1.0 μm, more preferably in the range of 0.03 μm to 0.5 μm, and particularly preferably in the range of 0.05 μm to 0.2 μm. If it is thicker than the above range, the protective film for optical members of the present invention may not exhibit sufficient adhesion, and if it is thinner than the above range, sufficient antistatic properties may not be exhibited. is there.

2. Pressure-sensitive adhesive layer The pressure-sensitive adhesive layer used in the present invention is formed on a transparent substrate described later, includes a pressure-sensitive adhesive layer forming material, and has desired adhesiveness.

(1) Adhesive layer forming material The adhesive layer forming material used for this invention contains an adhesive, a crosslinking agent, and a metal chelating agent at least.

(A) Adhesive The adhesive used in the present invention is not particularly limited as long as it has desired adhesiveness, and examples thereof include urethane-based, rubber-based, silicone-based, and acrylic-based adhesives. be able to. In the present invention, an acrylic pressure-sensitive adhesive is particularly preferable. This is because it is excellent in transparency and durability, is preferable as an optical member, has high heat resistance, and is low in cost.

  Examples of the acrylic pressure-sensitive adhesive used in the present invention include an acrylic ester copolymer obtained by copolymerizing an acrylic ester with another monomer.

Examples of the acrylate ester include ethyl acrylate, acrylate-n-butyl, acrylate-2-ethylhexyl, isooctyl acrylate, isononyl acrylate, hydroxylethyl acrylate, propylene glycol acrylate, acrylamide, and glycidyl acrylate. Etc. In the present invention, among them, ethyl acrylate, acrylic acid-n-butyl, acrylic acid-2-ethylhexyl, and the like can be preferably used. This is because the adhesiveness to the optical member is good.
Moreover, the said alkyl acrylate ester may be used independently and multiple may be used in mixture.

Examples of the other monomer include, for example, methyl acrylate, methyl methacrylate, styrene, acrylonitrile, vinyl acetate, acrylic acid, methacrylic acid, itaconic acid, hydroxylethyl acrylate, hydroxylethyl methacrylate, propylene glycol acrylate, Examples include acrylamide, methacrylamide, glycidyl acrylate, glycidyl methacrylate, dimethylaminoethyl methacrylate, tert-butylaminoethyl methacrylate, and n-ethylhexyl methacrylate. In the present invention, n-ethylhexyl methacrylate can be preferably used.
Moreover, the said other monomer may be used independently, and two or more may be mixed and used.

  The unit ratio (acrylic ester / other monomer) between the acrylic ester contained in the acrylic ester copolymer used as the acrylic adhesive in the present invention and the other monomer is the above acrylic acid. The ester copolymer is not particularly limited as long as it can exhibit a desired adhesive force, and can be appropriately set according to the use of the protective film for an optical member of the present invention.

The weight average molecular weight (Mw) of the acrylic ester copolymer used as the acrylic pressure-sensitive adhesive used in the present invention is particularly limited as long as the acrylic pressure-sensitive adhesive exhibits a desired adhesive force. However, it is preferably in the range of 200,000 to 2,500,000, and more preferably in the range of 600,000 to 2,200,000. It is because it can exhibit sufficient adhesive force by being in the said range. Further, by being in the above range, the pressure-sensitive adhesive layer can have sufficient strength, and when the protective sheet for optical members of the present invention is peeled from the optical member to be protected, This is because the pressure-sensitive adhesive layer can be prevented from causing cohesive failure. This is because by preventing the occurrence of such cohesive failure, it is possible to prevent a part of the pressure-sensitive adhesive layer from remaining on the surface of the optical member.
In addition, the said weight average molecular weight is a value of polystyrene conversion at the time of measuring by gel permeation chromatography (GPC).

(B) Cross-linking agent The cross-linking agent used in the present invention is an epoxy-based cross-linking agent or an isocyanate-based cross-linking agent, and can be cross-linked with the anti-static agent and the like contained in the pressure-sensitive adhesive and the anti-static agent layer forming material. Is.

  As an epoxy-type crosslinking agent used for this invention, a polyfunctional epoxy-type compound can be used, for example. Examples of the polyfunctional epoxy compounds include sorbitol polyglycidyl ether, polyglycerol polyglycidyl ether, pentaerythritol polyglycidyl ether, diglycerol polyglycidyl ether, glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, neopentyl glycol diglycidyl ether. 1,6-hexanediol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, polybutadiene diglycidyl ether, and the like.

  Examples of the isocyanate-based crosslinking agent used in the present invention include a polyisocyanate compound, a trimer of a polyisocyanate compound, a urethane prepolymer having an isocyanate group at a terminal obtained by reacting a polyisocyanate compound and a polyol compound, or And trimers of such urethane prepolymers. The polyisocyanate compound is not particularly limited, and 2,4-tolylene diisocyanate, 2,5-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, diphenylmethane-4,4'- Examples thereof include diisocyanate, 3-methyldiphenylmethane diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4′-diisocyanate, dicyclohexylmethane-2,4′-diisocyanate, and lysine isocyanate.

  As the cross-linking agent used in the present invention, any of the above can be suitably used, such as other materials contained in the pressure-sensitive adhesive layer forming material, antistatic agent layer forming material contained in the transition portion described above, and the like. It can be set accordingly.

  As content of the crosslinking agent used for this invention, although it changes also with the kind of said crosslinking agent, it exists in the range of 2.0 weight part-10.0 weight part with respect to 100 weight part of said adhesives. In particular, it is preferable that the amount be in the range of 3.5 parts by weight to 6.0 parts by weight. When the amount is less than the above range, it becomes difficult for the pressure-sensitive adhesive layer to have sufficient strength, the pressure-sensitive adhesive layer causes cohesive failure when peeling from the optical member, and may remain in the optical member, The antistatic agent contained in the transition part may not be sufficiently crosslinked with the antistatic agent included in the material for forming the antistatic agent layer, and it may be difficult to stably hold the antistatic agent in the transition part. Because. Moreover, when there are more than the said range, there exists a possibility that the intensity | strength of the said adhesive layer may be too low, or the said adhesive layer may become cloudy.

(C) Metal chelating agent The metal chelating agent used in the present invention has a metal element and a salt-forming site. When used together with the pressure-sensitive adhesive, the metal element, a carboxyl group possessed by the pressure-sensitive adhesive, etc. And can be cross-linked by chelating bond.
Specific examples of such metal chelates include aluminum isopropylate, aluminum butyrate, aluminum ethylate, aluminum ethyl acetoacetate, aluminum acetylacetonate, aluminum acetylacetonate bis, ethylacetoacetonate, and aluminum alkylacetoacetonate. Dipropoxy-bis (acetylacetonato) titanium, dibutoxytitanium-bis (octylene glycolate), dipropoxytitanium-bis (ethylacetoacetate), dipropoxytitanium-bis (lactate), dipropoxy Titanium-bis (triethanolaminate), di-n-butoxytitanium-bis (triethanolaminato), tri-n-butoxytitanium monostearate Titanium chelate compounds such as rutitanate dimer and poly (titanium acetylacetonate) and zirconium chelates such as zirconium tetraacetylacetonate, zirconium monoacetylacetonate, zirconium bisacetylacetonate, zirconium acetylacetonate bisethylacetoacetate and zirconium acetate Compounds, organic carboxylic acid metal salts such as zinc octylate, zinc laurate, zinc stearate, tin octylate, zinc chelate compounds such as acetylacetone zinc chelate, benzoylacetone zinc chelate, dibenzoylmethane zinc chelate, ethyl zinc acetoacetate chelate Is mentioned. Among them, in the present invention, aluminum chelates such as aluminum isopropylate, aluminum butyrate, aluminum ethylate, aluminum ethyl acetoacetate, aluminum acetylacetonate, aluminum acetylacetonate bis, ethylacetoacetonate, aluminum alkylacetoacetonate, etc. A compound can be preferably used. This is because it is easy to adjust the crosslinking rate for crosslinking the pressure-sensitive adhesive.

As content of the metal chelating agent used for this invention, although it changes also with the kind of said metal chelating agent, in the range of 0.06 weight part-0.50 weight part with respect to 100 weight part of said adhesives. Preferably there is. If the amount is less than the above range, the crosslinking rate when forming the pressure-sensitive adhesive layer may be slow, resulting in decreased productivity, or it may be difficult to stably hold the antistatic agent in the antistatic agent layer described above. Because there is. That is, the metal chelating agent has a high reaction rate with the pressure-sensitive adhesive that is the main component of the pressure-sensitive adhesive layer forming material, and the cross-linking reaction with the pressure-sensitive adhesive is performed preferentially over the cross-linking agent. Since the crosslinkable portion can be consumed in advance, the crosslinking agent can be crosslinked not only with the pressure-sensitive adhesive but also with the antistatic agent. However, when the content is low, the crosslinking agent cannot be sufficiently crosslinked with the antistatic agent, and it may be difficult to stably hold the transition portion. . Furthermore, when it becomes difficult to hold stably during the above-described antistatic treatment, as described in “B. Method for producing protective film for optical member” described later, the transition portion is a transparent group described later. When it is formed by transferring a part of the transition part containing the antistatic agent layer forming material on the pressure-sensitive adhesive layer on one side of the material, it is difficult to transfer the antistatic agent layer It is because it may become.
Moreover, even if it is a case where it is more than the said range, it is because an effect does not change and material cost increases.

(D) Other Additives The pressure-sensitive adhesive layer forming material used in the present invention is particularly limited as long as it has the above-mentioned pressure-sensitive adhesive, epoxy-based crosslinking agent or isocyanate-based crosslinking agent, and metal chelating agent. It may contain other additives instead of those.
Examples of such other additives include antioxidants and ultraviolet absorbers. The pressure-sensitive adhesive is a photosensitive pressure-sensitive adhesive obtained by polymerizing a photosensitive monomer component that is cured by light irradiation, such as the acrylate ester and other monomers constituting the acrylic pressure-sensitive adhesive, In the case where the pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive layer-forming material containing the photosensitive monomer component and then polymerizing and curing by irradiation with ultraviolet rays or visible light, the pressure-sensitive adhesive layer-forming material Is added with a photopolymerization initiator.

(2) Adhesive layer The adhesive layer used for this invention is formed on the transparent base material mentioned later, contains the said adhesive layer formation material, and has adhesiveness.

  The thickness of the pressure-sensitive adhesive layer used in the present invention is such that, as described in the section “B. Method for producing protective film for optical member” to be described later, the above-mentioned transition portion is formed on the antistatic agent layer. Although it is not particularly limited as long as it can be formed by transferring a part thereof, it is usually in the range of 3 μm to 200 μm, in particular in the range of 4 μm to 100 μm, particularly in the range of 5 μm to 50 μm. Preferably there is. This is because the transition portion can be easily formed by being in the above range.

3. Surface layer The surface layer used in the present invention is formed on a transparent substrate to be described later, and is made of the antistatic agent layer forming material. As such a surface layer, as illustrated in FIG. 2, the surface layer 4 is laminated so as to cover the surface of the transparent substrate 1, and as illustrated in FIG. 3, the surface layer 4 However, any of the aspects formed by partially adhering to the surface of the transparent substrate 1 without completely covering the transparent substrate 1 may be used.

As the film thickness of the surface layer used in the present invention, the surface layer may have a thickness necessary for exhibiting sufficient antistatic properties, and the thickness does not substantially exhibit antistatic properties. It may be sufficient and can be set suitably according to the use of the protective film for optical members of the present invention.
Here, the thickness necessary for exhibiting sufficient antistatic properties depends on whether the surface of the transparent substrate is completely covered and whether the surface is partially attached to the surface of the transparent substrate. Although it is different, it is preferably within a range of 0.05 μm to 5.0 μm.

4). Transparent substrate The transparent substrate used in the present invention is not particularly limited as long as it has transparency and flexibility and has sufficient strength so as not to damage the optical member to be protected. It is not something.
Examples of such a transparent substrate include olefin resins such as polyethylene, polypropylene, polyvinyl alcohol, and ethylene-vinyl alcohol copolymer, polyfluorinated ethylene, polyvinylidene fluoride, and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymers. Fluorine resins, vinyl chloride resins such as polyvinyl chloride or polyvinylidene chloride, acrylic resins such as polymethyl methacrylate, sulfone resins such as polyethersulfone, ketone resins such as polyetheretherketone, polyethylene terephthalate, polyethylene Examples thereof include thermoplastic polyester resins such as naphthalate, polyimide resins, and polyamide resins. Among them, polyethylene terephthalate can be preferably used in the present invention. This is because it is excellent in transparency and suitable for optical member applications.

  The transparent substrate used in the present invention is a surface treatment such as corona treatment or plasma treatment on the surface of the transparent substrate on which the pressure-sensitive adhesive layer is formed or an undercoat agent in order to improve the adhesion to the pressure-sensitive adhesive layer. (Primer) may be applied.

  The film thickness of the transparent substrate used in the present invention is not particularly limited as long as it can be bonded with good adhesion when bonded to an optical member and can be sufficiently protected from scratches. Rather, it is appropriately set according to the use of the protective film for optical members of the present invention, but is preferably in the range of 12 μm to 100 μm, and more preferably in the range of 16 μm to 50 μm. Is preferable, and it is particularly preferable to be in the range of 25 μm to 38 μm. This is because if it is thicker than the above range, it may be difficult to attach the optical member with good adhesion. Further, if it is thinner than the above range, it may be difficult to sufficiently protect from scratches and the like.

5. Protective film for optical members The adhesive strength of the protective film for optical members of the present invention is not particularly limited as long as it can be in close contact with the optical member to be protected, and is 0.01 N / 25 mm to 0. .49 N / 25 mm, preferably 0.03 N / 25 mm to 0.29 N / 25 mm, particularly 0.05 N / 25 mm to 0.20 N / 25 mm. It is preferable to be within. By being the said range, the stick-slip property at the time of unwinding from the state which wound the said protective film for optical members in the roll shape can be made more favorable. Further, it is possible to adhere to the optical member to be protected with sufficient strength and to be easily peeled off from the optical member when it becomes unnecessary.
In addition, the measuring method of the said adhesive force is SUS304 on the conditions based on the specification of JISZ0237, after cutting the strip-shaped test piece of the size of width 25mm x length 150mm from the protective film for optical members of this invention. Laminate to a SUS plate made of
Then, the peel strength when the film of the test piece is peeled in the length direction under the conditions of a peel angle of 180 °, a peel speed of 300 mm / min, and room temperature is measured as an adhesive strength. Further, for such 180 ° peel strength measurement, for example, a universal testing machine 5565 manufactured by Instron can be used.
In addition, the adhesive force of the said protective film for optical members refers to the adhesive force in the surface in the side in which the adhesive layer and the transition part were formed among the protective films for optical members of this invention.

The surface specific resistance value on the surface of the protective film for an optical member of the present invention on which the transition portion is formed is particularly limited as long as it can prevent charging that attracts dust and the like when peeling from the optical member. However, it is preferably 1.0 × 10 ¹³ Ω / □ or less, more preferably 1.0 × 10 ¹¹ Ω / □ or less, particularly 1.0 × 10 ¹⁰ Ω / □. The following is preferable. It is because it is sufficient to exhibit sufficient antistatic property by being in the above range, and attracting dust and the like and adhesion of dust and the like to the optical member can be prevented at the time of peeling.
In addition, as a measuring method of the said surface specific resistance value, the surface of the side in which the transition part of the said protective film for optical members was formed is based on JISK7194, and a digital insulation meter (Mitsubishi Chemical Corporation make: Lorestar) GP MCP-T610).

If the protective film for optical members of this invention has each layer mentioned above, it will not specifically limit, Other layers may be formed as needed.
As such other layers, for example, an antifouling layer formed on the surface layer for the purpose of preventing the protective film from being contaminated by oils or transferred adhesives, etc., for the purpose of preventing the protective film from being deteriorated by ultraviolet rays. Examples thereof include an ultraviolet absorbing layer formed on the surface layer and a hard coat layer formed on the surface layer for the purpose of preventing damage to the protective film.

Further, as the total light transmittance and haze of the protective film for optical members of the present invention, when the protective film for optical members is affixed to the optical member to be protected, foreign matter adhesion and scratches on the surface of the optical member The optical quality inspection is not particularly limited as long as the optical quality inspection is possible.
In the present invention, the total light transmittance is preferably in the range of 85% to 99%, and more preferably in the range of 90% to 99%.
The haze is preferably in the range of 0.5% to 4.5%, and more preferably in the range of 0.5% to 3.0%. Since the total light transmittance and the haze are within the above ranges, it is possible to easily perform an optical quality inspection with the protective film for an optical member of the present invention attached to the optical member. It is.
In addition, as said total light transmittance measuring method, according to JISK-7361, it measures with an integrating sphere type turbidimeter (Nippon Denshoku Industries Co., Ltd. make, NDH2000). Moreover, as a measuring method of the said haze, it measures with an integrating sphere type turbidimeter (Nippon Denshoku Industries Co., Ltd. make, NDH2000) according to JISK-7136.

  The method for producing the protective film for an optical member of the present invention is not particularly limited as long as each of the components of the protective film for an optical member is adhered with sufficient strength. The method similar to the content described in the section “Method for producing protective film for optical member” can be used.

6). Uses As the use of the protective film for optical members of the present invention, for example, it can be used by being bonded to the surface of various members such as optical members constituting electronic displays and electronic substrate materials. However, in recent years, it can be suitably used for protecting members constituting a display such as a liquid crystal display device whose screen size and definition have been rapidly increased. This is because there is a possibility that dust or the like adheres due to the large screen, and there is a case where the adverse effect on the cost due to a decrease in yield due to the adhesion of dust or the like becomes greater due to high definition.

B. Next, the manufacturing method of the protective film for optical members of this invention is demonstrated. The method for producing a protective film for an optical member of the present invention includes a transparent substrate, a pressure-sensitive adhesive layer formed on one surface of the transparent substrate, a transition portion formed on the pressure-sensitive adhesive layer, and the above A surface layer formed on the other surface of the transparent substrate on which the pressure-sensitive adhesive layer is not formed, and a method for producing a protective film for an optical member, on one surface of the transparent substrate, By applying an antistatic agent layer forming material containing an antistatic agent, an antistatic agent layer is formed, and the antistatic agent layer of the transparent substrate is not formed. On the other surface, a pressure-sensitive adhesive layer is formed by coating a pressure-sensitive adhesive, an epoxy-based cross-linking agent or an isocyanate-based cross-linking agent, and a pressure-sensitive adhesive layer-forming material having a metal chelating agent. The antistatic agent layer is formed on the other surface. The antistatic agent layer is formed by winding an adhesive layer forming step for forming a laminate for a protective film for an optical member on which the adhesive layer is formed, and the laminate for a protective film for an optical member into a roll. The antistatic agent layer is formed on the pressure-sensitive adhesive layer by rolling a part of the transfer layer onto the pressure-sensitive adhesive layer and winding the laminate for a protective film for an optical member wound up in the form of a roll. It has at least an unwinding step of forming a transition portion made of a material and forming a surface layer made of an antistatic agent layer forming material on the surface of the transparent base material.

The manufacturing method of such a protective film for optical members of this invention is demonstrated referring a figure. 4 and 5 are process diagrams showing an example of the method for producing the protective film for an optical member of the present invention. The manufacturing method of the protective film for optical members of this invention is applying the antistatic agent layer forming material containing an antistatic agent on one surface of the said transparent base material 1, as illustrated in FIG. Then, an antistatic agent layer 5 is formed (FIG. 4 (a)), and an adhesive, an epoxy-based crosslinking agent or an isocyanate is formed on the other surface of the transparent substrate 1 on which the antistatic agent layer 5 is not formed. The antistatic agent layer 5 is formed on one surface by forming the pressure-sensitive adhesive layer 2 by applying a pressure-sensitive adhesive layer-forming material having a crosslinking agent and a metal chelating agent. The laminated body 20 for protective films for optical members in which the said adhesive layer 2 was formed in the surface is formed (FIG.4 (b)). Next, the antistatic agent layer 5 and the pressure-sensitive adhesive are formed by winding up the optical film protective film laminate 20 in a roll shape to form an optical member protective film original fabric 30 (FIG. 4C). The layer 2 is brought into close contact (FIG. 4D), and a part of the antistatic agent layer 5 is transferred onto the pressure-sensitive adhesive layer 2. Here, FIG.4 (d) is the figure which expanded the location where the protective film for optical members shown by A of FIG.4 (c) laminated | stacked two layers.
Then, a transition portion made of the antistatic agent layer forming material is formed on the pressure-sensitive adhesive layer by unwinding the optical film protective film laminate from the protective film for optical member 30, and The protective film 10 for an optical member, in which the surface layer made of the antistatic agent layer forming material is formed on the surface of a transparent substrate, is produced (FIG. 5).
Here, FIG. 4A is an antistatic agent layer forming step, and FIG. 4B is an adhesive layer forming step. Moreover, FIG.4 (c)-(d) is a transfer process, FIG. 5 is an unwinding process.

According to the present invention, by performing the transfer step described above, the pressure-sensitive adhesive layer and the antistatic agent layer are brought into close contact with each other, and a part of the antistatic agent layer is transferred onto the pressure-sensitive adhesive layer. The protective film for an optical member obtained after the unwinding step may have the transition portion formed on the pressure-sensitive adhesive layer. For this reason, the protective film for optical members finally obtained can be effectively prevented from being charged when being peeled from the optical member, and can be effectively prevented from attracting and adhering dust and the like. can do.
In addition, since the transition portion is formed on the pressure-sensitive adhesive layer, the adhesiveness is appropriately adjusted. Therefore, the protective film for an optical member produced by the production method of the present invention is rolled. It is possible to suppress the occurrence of stick-slip when unwinding from the state of being wound around, so that the stick-slip property can be improved. That is, in the unwinding step, it is possible to suppress the occurrence of stick slip, and it is possible to manufacture a protective film for an optical member that has no horizontal stripes.

Here, in the transition step, a mechanism in which a part of the antistatic agent layer is transferred onto the pressure-sensitive adhesive layer by winding the laminate for a protective film for an optical member into a roll is not clear, A mechanism may be considered in which a part of the antistatic agent layer forming material contained in the antistatic agent layer and the pressure-sensitive adhesive layer are in close contact with each other with a stronger force than the antistatic agent layer forming materials.
In this case, the transition part included in the protective film for an optical member produced by the production method of the present invention is such that the antistatic agent layer forming material that is in close contact with the pressure-sensitive adhesive layer is strongly charged in the unwinding step. It is considered that the antistatic agent layer-forming material is partly present on the pressure-sensitive adhesive layer 2 as shown in FIG.
As a result, since the transition part is partially formed on the surface of the pressure-sensitive adhesive layer, the adhesiveness of the protective film for an optical member produced by the production method of the present invention is appropriately adjusted, as described above. It is considered that the stick-slip property can be improved.

  The manufacturing method of the protective film for optical members of this invention has an antistatic agent layer forming process, an adhesive layer forming process, a transfer process, and an unwinding process. Hereinafter, each process of the manufacturing method of the protective film for optical members of this invention is demonstrated.

1. Antistatic agent layer forming step The antistatic agent layer forming step used in the present invention is carried out by applying an antistatic agent layer-forming material containing an antistatic agent on one surface of the transparent substrate, thereby preventing the antistatic agent layer. The agent layer is formed with a uniform film thickness.

  In this step, as a method of coating the antistatic agent layer forming material and forming the antistatic agent layer, for example, preparing an antistatic agent solution in which the antistatic agent layer forming material is dissolved in a solvent, An example is a method in which the antistatic agent solution is applied onto the transparent substrate and dried. Further, when the antistatic agent layer forming material has a photosensitive resin as a binder, the antistatic agent layer forming material is applied as it is without dissolving it in a solvent, and light is applied to the coating film. It may be cured by irradiation.

  The solvent contained in the antistatic agent solution used in this step is not particularly limited as long as it can dissolve or uniformly disperse the antistatic agent layer forming material. For example, acetone, methyl ethyl ketone , Methyl isobutyl ketone, cyclohexanone, benzene, toluene, xylene, chlorobenzene, tetrahydrofuran, methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, ethyl acetate, 1,4-dioxane, 1,2-dichloroethane, dichloromethane, chloroform , Methanol, ethanol or isopropanol, distilled water, ion-exchanged water and the like.

  In addition, the transparent base material and antistatic agent layer forming material used in this step have the same contents as those described in the above section “A. Protective film for optical members”, so description thereof is omitted here. To do.

  The film thickness of the antistatic agent layer used in this step can be partially transferred to the pressure-sensitive adhesive layer in the transfer step described later, and the transfer portion and the surface layer can be formed by the unwinding step described later. If it is, it will not specifically limit, For example, it is preferable to exist in the range of 0.05 micrometer-5.0 micrometers, and it is preferable to set it especially in the range of 0.1 micrometer-2.0 micrometers. It is because it is easy to form the said transition part and a surface layer because it is the said range.

  The coating method of the antistatic agent layer forming material used in this step is not particularly limited as long as it is a method capable of coating the antistatic agent layer forming material with a uniform film thickness. For example, roll coating method, gravure coating method, micro gravure coating method, reverse coating method, roll brush method, spray coating method, air knife coating method, impregnation method, curtain coating method, die coating method A doctor blade method, a comma coating method, or the like can be used.

  In this step, the method for drying the coated antistatic agent layer-forming material is not particularly limited as long as the solvent can be reduced to a desired content or less. Hot air drying, infrared heating A known method such as the above can be used.

  In this step, when the antistatic agent layer forming material has a photosensitive resin as a binder, the coating method of the coated antistatic agent layer forming material is generally applied as a light irradiation method. The antistatic agent layer can be formed by curing by irradiating light used for curing the photosensitive resin, for example, ultraviolet light, visible light, electron beam or the like.

2. Pressure-sensitive adhesive layer forming step The pressure-sensitive adhesive layer forming step used in the present invention comprises a pressure-sensitive adhesive, an epoxy-based crosslinking agent or an isocyanate-based crosslinking on the other surface of the transparent base material on which the antistatic agent layer is not formed. A pressure-sensitive adhesive layer is formed by applying a pressure-sensitive adhesive layer-forming material having a crosslinking agent and a metal chelating agent, and the antistatic agent layer is formed on one surface, and the pressure-sensitive adhesive is formed on the other surface. It is the process of forming the laminated body for protective films for optical members in which the layer was formed.

  In this step, the pressure-sensitive adhesive layer forming material is applied and the pressure-sensitive adhesive layer is formed by preparing a pressure-sensitive adhesive solution in which the pressure-sensitive adhesive layer forming material is dissolved in a solvent and applying the pressure-sensitive adhesive solution. The method of doing can be mentioned. When the pressure-sensitive adhesive contained in the pressure-sensitive adhesive layer forming material is a liquid photosensitive pressure-sensitive adhesive, the pressure-sensitive adhesive layer forming material is applied as it is without dissolving it in a solvent, and light is applied to the coating film. A method of curing by irradiation may be used.

  The solvent used in this step is not particularly limited as long as it can dissolve or uniformly disperse the pressure-sensitive adhesive layer forming material. Specifically, the above-mentioned “1. Antistatic agent layer formation”. The thing similar to what was described in the term of "process" can be used.

  In this step, as the method for applying the adhesive layer forming material, the drying method, and the light irradiation method, the same methods as those described in the above section “1. Antistatic agent layer forming step” may be used. it can.

  The pressure-sensitive adhesive layer and the pressure-sensitive adhesive layer forming material used in this step have the same contents as those described in the section “2. Pressure-sensitive adhesive layer” of the above “A. Protective film for optical members”. The description in is omitted.

3. Transition Step The transition step used in the present invention is to form a protective film original film for an optical member by winding up the laminate for a protective film for an optical member in a roll shape, and a part of the antistatic agent layer is adhered to the adhesive layer. This is a step of transferring onto the agent layer.
Here, in the transition step, the antistatic agent layer may be partly transferred onto the pressure-sensitive adhesive layer by winding the optical film protective film laminate in a roll shape. A mechanism in which a part of the agent layer forming material and the pressure-sensitive adhesive layer adhere to each other with a stronger force than the antistatic agent layer forming materials can be considered.

  In this step, as the winding direction when the laminate for the protective film for an optical member is wound into a roll shape with the pressure-sensitive adhesive layer and the antistatic agent layer being in close contact, the pressure-sensitive adhesive layer is It may be wound so that it is on the inside, or may be wound so that the antistatic agent layer is on the inside.

  In this step, when the laminate for a protective film for an optical member is wound into a roll shape while adhering the pressure-sensitive adhesive layer and the antistatic agent layer, the pressure-sensitive adhesive layer and the antistatic agent layer You may perform the heat processing which heats. This is because the antistatic agent layer can be easily transferred onto the pressure-sensitive adhesive layer by performing the heat treatment. As the heating temperature in the heat treatment, the pressure-sensitive adhesive layer and the antistatic agent layer are preferably within a range of 25 ° C. to 100 ° C., and more preferably within a range of 40 ° C. to 80 ° C. . This is because the transition cannot be promoted below the above range, and it is difficult to adjust the transition amount of the antistatic agent layer above the above range.

  Moreover, as a method for performing the heat treatment, a known heating means can be used, and for example, a method of irradiating electromagnetic waves such as infrared rays can be mentioned.

4). Unwinding process The unwinding process used for this invention consists of an antistatic agent layer forming material on an adhesive layer by unwinding the said laminated body for protective films for optical members wound up by the said roll shape. In this step, a transition part is formed, and a surface layer made of the same material as the antistatic agent layer forming material contained in the transition part is formed on the surface of the transparent substrate. Here, the surface layer refers to a layer made of an antistatic agent-forming material that has not been transferred to the pressure-sensitive adhesive layer side and remained on the antistatic agent layer side in this step.

In this step, the unwinding strength when unwinding the protective film for an optical member from the original protective film for an optical member, which is the laminate for the protective film for an optical member, is 0.29 N / 25 mm or less. In particular, it is preferably within a range of 0.01 N / 25 mm to 0.10 N / 25 mm. This is because, when the unwinding strength is in the above range, unwinding failure such as inability to unwind while the laminated protective films for optical members are in close contact with each other can be prevented.
In addition, as a method for measuring the unwinding strength, a strip-shaped test piece having a width of 25 mm and a length of 150 mm from the original protective film for an optical member is laminated in two layers. It is cut out as it is (an antistatic agent layer / transparent substrate / adhesive layer / antistatic agent layer / transparent substrate / adhesive layer overlapped).
And the laminated body for protective films for optical members of a test piece was peeled from the other laminated body for protective films for optical members in the length direction at a peeling angle of 180 °, a peeling speed of 300 mm / min, and at room temperature. The peel strength at the time is measured as the unwinding strength. Further, for such 180 ° peel strength measurement, for example, a universal testing machine 5565 manufactured by Instron can be used.

  The unwinding speed of the transparent base material in this step is not particularly limited as long as the transition part and the surface layer can be stably formed, and is manufactured by the manufacturing method of the present invention. It sets suitably according to the use etc. of the protective film for optical members.

  Since the transition part and the surface layer formed in this step have the same contents as those described in the above section “A. Protective film for optical members”, description thereof is omitted here.

5. Manufacturing method of protective film for optical member The manufacturing method of the protective film for optical member of the present invention is particularly limited as long as it has an antistatic agent layer forming step, an adhesive layer forming step, a transfer step, and an unwinding step. It may have other processes instead of those.

As such another process, after the said laminated body for protective films for optical members is wound up in roll shape, making the said adhesive layer and the said antistatic agent layer closely_contact | adhere, the cohesive force of an adhesive layer In order to improve the viscosity, and to transfer a part of the antistatic agent layer on the pressure-sensitive adhesive layer and form a transition portion, it may have an aging process of maintaining a roll shape for a certain period of time. .
The holding period in the aging step is not particularly limited as long as it can transfer a desired amount of the antistatic agent layer and form the transfer portion, and is manufactured by the manufacturing method of the present invention. It is set according to the use of the protective film for optical members.

  In the aging step, it is preferable to perform a heat treatment for heating the pressure-sensitive adhesive layer and the antistatic agent layer. This is because the antistatic agent layer can be easily transferred onto the pressure-sensitive adhesive layer. The heating temperature in the heat treatment may be the same as that described in the above section “3. Transition step”.

  In the present invention, the transfer step may be performed after the antistatic agent layer forming step and the pressure-sensitive adhesive layer forming step, and the unwinding step may be performed after the transfer step. Either the inhibitor layer forming step or the pressure-sensitive adhesive layer forming step may be performed first or simultaneously.

C. Next, the protective film original fabric for optical members of the present invention will be described. The protective film original film for optical members of the present invention is a protective film original film for optical members wound in a roll shape, and the protective film for optical members after unwinding is the protective film for optical members described above. It is a feature.

  Such a protective film original fabric for an optical member of the present invention will be described with reference to the drawings. FIG. 6 is a schematic cross-sectional view showing an example of the protective film raw material for an optical member of the present invention, and FIG. 7 is a schematic cross-sectional view showing an enlarged portion where two layers of the protective film for an optical member shown in FIG. FIG. As illustrated in FIG. 6, the protective film original fabric 30 for the optical member of the present invention is formed by laminating an antistatic agent layer 5 made of an antistatic agent layer forming material, a transparent substrate 1, and an adhesive layer 2 in this order. The optical member protective film laminate 20 is rolled into a roll, and the optical member protective film when unrolled is a surface layer, a transparent substrate, and an adhesive layer as illustrated in FIG. Thus, the protective film 10 for an optical member is formed by laminating transition portions in this order.

According to the present invention, the protective film for an optical member can be easily obtained by the film unwound from the protective film for the optical member wound into a roll being the protective film for an optical member described above. it can.
Moreover, the separator closely_contact | adhered to the surface in which the adhesive layer of the said protective film for optical members was normally formed becomes unnecessary, and the cost reduction of the said protective film for optical members can be achieved.
Furthermore, when the film unwound from the roll of the protective film for optical members wound in a roll is the protective film for optical members described above, the occurrence of stick-slip may be reduced when the film is unwound. it can. For this reason, the protective film for optical members unwound from the said protective film original film for optical members can be made into a thing without a horizontal stripe.

  The protective film for an optical member has the same contents as those described in the above section “A. Protective film for an optical member”, and thus description thereof is omitted here.

  As the antistatic agent layer used in the present invention, those described in the above-mentioned section “B. Method for producing protective film for optical member” can be used, and therefore description thereof is omitted here.

The unwinding strength at the time of unwinding the protective film for an optical member from the original protective film for an optical member of the present invention is preferably 0.29 N / 25 mm or less, particularly 0.01N. / 25 mm to 0.10 N / 25 mm is preferable. This is because, when the unwinding strength is in the above range, unwinding failure such as inability to unwind while the laminated protective films for optical members are in close contact with each other can be prevented.
The method for measuring the unwinding strength can be the same as that described in the above section “B. Method for producing protective film for optical member”.

  The method for producing the protective film for an optical member of the present invention is not particularly limited as long as the protective film for an optical member after unwinding becomes the above-described protective film for an optical member. The surface layer, the transparent base material, the pressure-sensitive adhesive layer, and the transition part, which have the same configuration as the protective film for optical members, are manufactured in this order, and then rolled up into a roll or After producing the laminate for a protective film for an optical member in which the antistatic agent layer, the transparent base material, and the pressure-sensitive adhesive layer that can be separated and become a transition portion and a surface layer are laminated in this order, the product is wound into a roll. The method of taking can be mentioned. In the present invention, the latter method is particularly preferable. This is because the number of steps is small and the productivity can be improved. About the detail of such a manufacturing method, the method similar to the content described in the above-mentioned "B. Manufacturing method of protective film for optical members" can be used.

The present invention is not limited to the above embodiment. The above-described embodiment is an exemplification, and the technical idea described in the claims of the present invention has substantially the same configuration and exhibits the same function and effect regardless of the case. It is included in the technical scope of the invention.
For example, as illustrated in FIG. 9, the protective film for the optical member is laminated with the protective film 10 for the optical member, which is an enlarged portion where the protective film for the optical member shown by B in FIG. 6 is laminated. It may have the form.

  Next, the present invention will be described more specifically with reference to examples and comparative examples.

[Example 1]
1. Formation of antistatic agent layer A single-sided corona-treated PET (S105 manufactured by Toray Industries, Inc.) having a thickness of 38 μm was prepared as a transparent substrate, and an antistatic agent solution of the following formulation was applied to the corona-treated surface of the single-sided corona-treated PET at 50 ° C. Then, under a drying condition of 30 seconds, coating was carried out by a gravure printing method so that the film thickness after drying was 1 μm, and an antistatic function-added PET having an antistatic agent layer was obtained.

<Antistatic agent solution>
Quaternary ammonium salt + binder (NR-121X made by Colcoat) 100 parts by weight Isopropyl alcohol 2000 parts by weight

2. Formation of pressure-sensitive adhesive layer The film thickness after drying the pressure-sensitive adhesive solution of the following formulation on the untreated surface (surface not coated with the antistatic agent) of the antistatic function-imparted PET at 100 ° C. for 1 minute. Was applied by a die coating method to form a pressure-sensitive adhesive layer to obtain a laminate for a protective film for an optical member.

<Adhesive solution>
Acrylic ester adhesive (ATR340 manufactured by Seiden Chemical) 100 parts by weight Isocyanate-based crosslinking agent (K200 manufactured by Seiden Chemical) 4.75 parts by weight Metal chelating agent (M2 manufactured by Seiden Chemical) 0.12 parts by weight Toluene 10 parts by weight

3. Preparation of protective film for optical member Next, the laminate for protective film for optical member was wound in a tape shape so that the pressure-sensitive adhesive layer and the antistatic agent layer were in contact with each other, and then aged at 40 ° C. for 72 hours. Processed.
By unwinding the laminate for a protective film for an optical member wound up in a tape shape, a transition portion was formed on the pressure-sensitive adhesive layer, and a surface layer was formed on the corona-treated surface of PET which is a transparent substrate. A protective film for an optical member was obtained.

[Comparative Example 1]
A protective film for an optical member was obtained by the same production method as in Example 1 except that the formulation of the pressure-sensitive adhesive solution was changed as follows.

<Adhesive solution>
Acrylic ester adhesive (ATR340 manufactured by Seiden Chemical) 100 parts by weight Isocyanate-based crosslinking agent (K200 manufactured by Seiden Chemical) 0.030 parts by weight Metal chelating agent (M2 manufactured by Seiden Chemical) 0 parts by weight Toluene 10 parts by weight

[Example 2]
A protective film for an optical member was produced in the same manner as in Example 1 except that the composition of the pressure-sensitive adhesive solution was changed as follows.

<Adhesive solution>
Acrylic ester adhesive (SK1439U, manufactured by Soken Chemical) 100 parts by weight Epoxy crosslinking agent (E-50C, manufactured by Soken Chemical) 10 parts by weight Metal chelating agent (M5A, manufactured by Soken Chemical) 0.33 parts by weight Toluene 10 parts by weight

[Comparative Example 2]
A protective film for an optical member was obtained by the same production method as in Example 1 except that the composition of the pressure-sensitive adhesive solution was changed as follows.

<Adhesive solution>
Acrylic ester adhesive (SK1439U, manufactured by Soken Chemical) 100 parts by weight Epoxy crosslinking agent (E-50C, manufactured by Soken Chemical) 1.8 parts by weight Metal chelating agent (M5A, manufactured by Soken Chemical) 0 parts by weight Toluene 10 parts by weight

[Evaluation]
About Examples 1-2 and Comparative Examples 1-2, it measured about the unwinding strength, the adhesive force of the protective film for optical members, the surface specific resistance value of the transition part side and the surface layer side of the protective film for optical members, and the result Table 1 shows.
In addition, about the measuring method, the method mentioned above was used.

  As shown in Table 1, in Examples 1 and 2, it was confirmed that the surface specific resistance value on the transition portion side was low and had sufficient antistatic properties. It was also confirmed that the adhesive strength was sufficient and the unwinding strength was low. On the other hand, in Comparative Examples 1 and 2, the surface specific resistance value on the transition portion side was high, the antistatic property was not sufficient, and the unwinding strength was high.

It is a schematic sectional drawing which shows an example of the optical member protective film of this invention. It is a schematic sectional drawing which shows an example of the surface layer used for this invention. It is a schematic sectional drawing which shows the other example of the surface layer used for this invention. It is process drawing which shows an example of the antistatic agent layer formation process used for this invention, an adhesive layer formation process, and a transfer process. It is process drawing which shows an example of the unwinding process used for this invention. It is a schematic sectional drawing which shows an example of the protective film original fabric for optical members of this invention. It is sectional drawing which shows an example of the laminated part of the protective film for optical members in the original film for protective films for optical members of this invention. It is explanatory drawing explaining the protective film original fabric for optical members of this invention. It is sectional drawing which shows the other example of the laminated part of the protective film for optical members in the protective film original fabric of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Transparent base material 2 ... Adhesive layer 3 ... Transition part 4 ... Surface layer 5 ... Antistatic agent layer 10 ... Optical member protective film 20 ... Optical member protective film laminated body 30 ... Optical member protective film original fabric

Claims (6)

A transparent substrate;
A pressure-sensitive adhesive layer formed on one surface of the transparent substrate, and including a pressure-sensitive adhesive, a cross-linking agent of an epoxy-based cross-linking agent or an isocyanate-based cross-linking agent, and a pressure-sensitive adhesive layer forming material having a metal chelating agent;
A transition portion formed on the pressure-sensitive adhesive layer and made of an antistatic agent layer-forming material containing an antistatic agent;
A surface layer made of the antistatic agent-forming material, formed on the other surface of the transparent base material on which the pressure-sensitive adhesive layer is not formed,
The content of the crosslinking agent and metal chelating agent is within the range of 3.5 to 10.0 parts by weight and 0.06 to 0.5 parts by weight, respectively, with respect to 100 parts by weight of the pressure-sensitive adhesive. range der of is,
The transition part is a protective film for an optical member , wherein an antistatic agent layer forming material is partially present on the pressure-sensitive adhesive layer . 2. The protective film for an optical member according to claim 1, wherein the adhesive strength of the protective film for an optical member is 0.01 N / 25 mm to 0.49 N / 25 mm. The said adhesive is an acrylic adhesive, The protective film for optical members of Claim 1 or Claim 2 characterized by the above-mentioned. A transparent substrate;
An adhesive layer formed on one surface of the transparent substrate;
A transition formed on the adhesive layer;
A surface layer formed on the other surface of the transparent substrate on which the pressure-sensitive adhesive layer is not formed;
A method for producing a protective film for an optical member comprising:
An antistatic agent layer forming step of forming an antistatic agent layer by applying an antistatic agent layer-forming material containing an antistatic agent on the other surface of the transparent substrate;
A pressure-sensitive adhesive layer-forming material comprising a pressure-sensitive adhesive, an epoxy-based crosslinking agent or an isocyanate-based crosslinking agent, and a metal chelating agent on one surface of the transparent substrate on which the antistatic agent layer is not formed. The pressure-sensitive adhesive layer is formed by coating, the antistatic agent layer is formed on the other surface, and the pressure-sensitive adhesive layer is formed on the one surface to form a laminate for a protective film for an optical member. Agent layer forming step,
A transfer step of transferring a part of the antistatic agent layer onto the pressure-sensitive adhesive layer by winding the laminate for a protective film for optical members into a roll;
On the pressure-sensitive adhesive layer, a transition part made of the antistatic agent layer-forming material is formed on the pressure-sensitive adhesive layer by unwinding the protective film laminate for an optical member wound up in the form of a roll. An unwinding step of forming a surface layer made of the antistatic agent layer forming material,
The content of the crosslinking agent and metal chelating agent is within the range of 3.5 to 10.0 parts by weight and 0.06 to 0.5 parts by weight, respectively, with respect to 100 parts by weight of the pressure-sensitive adhesive. The manufacturing method of the protective film for optical members characterized by being in the range of these. It is the protective film original film for optical members wound by roll shape, Comprising: The protective film for optical members after unwinding is a protective film for optical members in any one of Claim 1- Claim 3. An original film for a protective film for an optical member. 6. The protective film original fabric for an optical member according to claim 5, wherein the unwinding strength is 0.29 N / 25 mm or less.

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