CN105385370B - Surface protection film and optical component bonded with same - Google Patents
Surface protection film and optical component bonded with same Download PDFInfo
- Publication number
- CN105385370B CN105385370B CN201510397287.0A CN201510397287A CN105385370B CN 105385370 B CN105385370 B CN 105385370B CN 201510397287 A CN201510397287 A CN 201510397287A CN 105385370 B CN105385370 B CN 105385370B
- Authority
- CN
- China
- Prior art keywords
- film
- adhesive layer
- protective film
- release
- surface protective
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B27/00—Layered products comprising a layer of synthetic resin
- B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B32—LAYERED PRODUCTS
- B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
- B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
- B32B7/04—Interconnection of layers
- B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
-
- C—CHEMISTRY; METALLURGY
- C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
- C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
- C09J133/00—Adhesives based on homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by only one carboxyl radical, or of salts, anhydrides, esters, amides, imides, or nitriles thereof; Adhesives based on derivatives of such polymers
- C09J133/04—Homopolymers or copolymers of esters
- C09J133/06—Homopolymers or copolymers of esters of esters containing only carbon, hydrogen and oxygen, the oxygen atom being present only as part of the carboxyl radical
- C09J133/08—Homopolymers or copolymers of acrylic acid esters
-
- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B5/00—Optical elements other than lenses
- G02B5/30—Polarising elements
Abstract
The invention provides a surface protective film which can be used for an optical film having a surface with concave-convex, has little pollution to an adherend and no change with time of low pollution performance to the adherend, and has excellent anti-stripping electrostatic performance without time degradation, and an optical component using the surface protective film. The surface protection film is characterized in that an adhesive layer (2) is formed on one surface of a base material film (1) composed of transparent resin, and a stripping film (5) with a stripping agent layer (4) is laminated on the adhesive layer (2), wherein the stripping film (5) is formed by laminating the stripping agent layer (4) on one surface of a resin film (3), the stripping agent layer (4) comprises a stripping agent with resin containing long chain alkyl as a main component and an antistatic agent which does not react with the stripping agent, the antistatic agent component is transferred from the stripping film (5) to the surface of the adhesive layer (2), and the stripping electrostatic pressure when the adhesive layer (2) is stripped from an adherend is reduced.
Description
Technical Field
The present invention relates to a surface protective film to be bonded to a surface of an optical member (hereinafter, also referred to as "optical film") such as a polarizing plate, a retardation plate, or a lens film for a display. More specifically, the present invention provides a surface protective film which causes little contamination to an adherend, and further provides a surface protective film which is free from deterioration with time (does not deteriorate with time) and has excellent antistatic properties, and an optical member to which the surface protective film is bonded.
Background
Conventionally, when optical films such as polarizing plates, retardation plates, lens films for displays, antireflection films, hard coat films, and transparent conductive films for touch panels, and displays and other optical products using these films are manufactured and transported, a surface protective film is bonded to the surface of the optical film to prevent surface contamination and scratches in subsequent processes. In order to save labor and time for peeling and then bonding the surface protective film and improve work efficiency, visual inspection of an optical film as a product may be performed directly in a state where the surface protective film is bonded to the optical film.
Conventionally, in order to prevent scratches and dirt from adhering to a substrate film in the production process of an optical product, a surface protective film in which an adhesive layer is provided on one surface of the substrate film has been generally used. The surface protective film is bonded to the optical film via an adhesive layer having a slight adhesive force. The reason why the adhesive layer is set to a slight adhesive force is that the adhesive layer can be easily peeled off when the used surface protective film is peeled off and removed from the surface of the optical film, and the adhesive layer is prevented from adhering to the optical film as an adherend and remaining on the optical film (so-called prevention of adhesive residue).
In recent years, in the production process of liquid crystal display panels, a peeling static voltage generated when a surface protective film bonded to an optical film is peeled off and removed destroys circuit components such as a driver IC for controlling a display screen of a liquid crystal display, and also damages the alignment of liquid crystal molecules, and these phenomena occur even though the number of occurrences is small.
In addition, in order to reduce power consumption of the liquid crystal display panel, the driving voltage of the liquid crystal material tends to be reduced, and the breakdown voltage of the driver IC also tends to be reduced accordingly. Recently, it is required to control the peeling electrostatic voltage within the range of +0.7kV to-0.7 kV.
In recent years, with the spread of 3D displays (stereoscopic displays), a Film of FPR (Film Patterned Retarder) is sometimes bonded to the surface of an optical Film such as a polarizing plate. After peeling the surface protective film attached to the surface of an optical film such as a polarizing plate, an FPR film is attached. However, when the surface of an optical film such as a polarizing plate is contaminated with an adhesive or an antistatic agent used for a surface protective film, there is a problem that it is difficult to adhere the FPR film. Therefore, the surface protective film used for this application is required to have less contamination on the adherend.
On the other hand, some liquid crystal panel manufacturers have adopted the following method as a method for evaluating the staining property of the surface protective film to the adherend: the surface protective film attached to an optical film such as a polarizing plate is peeled off, reattached in a state where air bubbles are mixed, the reattached article is subjected to a heat treatment under a predetermined condition, and then the surface protective film is peeled off to observe the surface of the adherend. In this evaluation method, even if the surface contamination of the adherend is slight, if there is a difference in the contamination of the adherend surface between the portion where the air bubbles are mixed and the portion of the surface protective film that is in contact with the adhesive, the air bubbles may remain as air bubble marks (also referred to as "air bubble stains"). Therefore, as a method of evaluating the staining property of the adherend surface, a very strict evaluation method is used. In recent years, even if the determination is made by such a strict evaluation method, a surface protective film having no problem in terms of the surface staining of the adherend is required.
In order to prevent defects caused by high peeling static voltage when peeling a surface protective film from an optical film as an adherend, there has been proposed a surface protective film using an adhesive layer containing an antistatic agent for reducing the peeling static voltage.
For example, patent document 1 discloses a surface protective film using a binder composed of an alkyltrimethylammonium salt, a hydroxyl group-containing acrylic polymer, and a polyisocyanate.
Patent document 3 discloses an adhesive composition comprising an acrylic polymer, a polyether polyol compound, and an alkali metal salt treated with an anion-adsorptive compound, and a surface protective film using the same.
Patent document 4 discloses an adhesive composition comprising an ionic liquid, an alkali metal salt, and a polymer having a glass transition temperature of 0 ℃ or lower, and a surface protective film using the same.
In the above patent documents 1 to 4, an antistatic agent is added to the inside of the adhesive layer. However, the thicker the adhesive layer is, the more the antistatic agent moves from the adhesive layer to the adherend to which the surface protection film is attached, with the passage of time after attachment to the adherend. When the amount of the antistatic agent transferred to the adherend is increased, the appearance quality of the optical film as the adherend may be deteriorated, or the adhesion of the FPR film may be deteriorated when the FPR film is bonded.
Another problem arises when the thickness of the adhesive is reduced in order to reduce such a change over time in which the antistatic agent moves from the adhesive layer to the adherend. For example, when the film is used for an optical film having irregularities on the surface, such as a polarizing plate subjected to an anti-glare treatment for anti-glare purposes, there are problems as follows: the adhesive cannot follow the unevenness of the surface of the optical film and air bubbles are mixed, or the adhesive force is reduced due to the reduction of the adhesion area between the optical film and the adhesive, and the surface protective film floats or peels off during use.
Documents of the prior art
Patent document
Patent document 1: japanese patent laid-open publication No. 2005-131957
Patent document 2: japanese patent laid-open No. 2005-330464
Patent document 3: japanese patent laid-open publication No. 2005-314476
Patent document 4: japanese patent laid-open publication No. 2006-152235
Disclosure of Invention
Problems to be solved by the invention
The present invention has been made in view of the above circumstances, and an object thereof is to provide a surface protective film which is usable even for an optical film having an uneven surface, causes little contamination to an adherend, has low contamination to the adherend, and does not change with time, and has excellent antistatic properties without deterioration with time (without deterioration with time), and an optical member using the surface protective film.
Means for solving the problems
The present inventors have made extensive studies on this problem.
In order to reduce contamination of an adherend and also reduce change over time in the contamination property, it is necessary to reduce the amount of the antistatic agent which is supposed to cause contamination of the adherend. However, when the amount of the antistatic agent is reduced, the peeling electrostatic voltage at the time of peeling the surface protective film from the adherend becomes high. The present inventors studied a method of suppressing the peeling electrostatic voltage at the time of peeling the surface protective film from the adherend at a low level without increasing the absolute amount of the antistatic agent.
As a result, the inventors have found that a surface protective film capable of suppressing the amount of charge at the time of peeling can be obtained by forming an adhesive layer without adding an antistatic agent to an adhesive and mixing them, applying an adhesive composition containing no antistatic agent, drying the adhesive composition, laminating an adhesive layer, and then attaching a release film having a release agent layer containing an antistatic agent so that the adhesive layer and the release agent layer are in contact with each other, and transferring an appropriate amount of an antistatic component from the release film side to impart the surface of the adhesive layer, and have completed the present invention based on the above finding.
That is, the present invention provides a surface protection film in which an adhesive layer is formed on one surface of a base film made of a transparent resin, and a release film having a release agent layer is laminated on the adhesive layer, wherein the release film is formed by laminating a release agent layer on one surface of a resin film, the release agent layer contains a release agent containing a long-chain alkyl group-containing resin as a main component and an antistatic agent that does not react with the release agent, and the antistatic agent component is transferred from the release film to the surface of the adhesive layer, thereby reducing a release static pressure when the adhesive layer is released from an adherend.
In addition, the antistatic agent is preferably an alkali metal salt.
Preferably, the adhesive layer is formed by crosslinking a (meth) acrylate copolymer.
The surface potential when the surface protective film is peeled from the optical film as an adherend is preferably +0.7kV to-0.7 kV.
Further, it is preferable that the peeling force of the peeling film when peeled from the adhesive layer is 0.005 to 0.3N/50 mm.
The present invention also provides an optical member to which the surface protective film is bonded.
Effects of the invention
The surface protective film of the present invention causes little contamination to an adherend and has low contamination to the adherend without change over time (without change over time). In addition, according to the present invention, even if the adherend is an optical film having irregularities on the surface, such as an AG polarizing plate, the film can be used. The surface protective film according to the present invention can provide a surface protective film which can suppress a peeling static voltage generated when peeling the surface protective film from an optical film as an adherend at a low level and has excellent anti-peeling static performance without deterioration with time, and an optical member using the surface protective film.
The surface protective film according to the present invention can reliably protect the surface of the optical film, and therefore can improve the production efficiency and the yield.
Drawings
Fig. 1 is a cross-sectional view showing the concept of the surface protective film of the present invention.
Fig. 2 is a sectional view showing a state where the release film is peeled off from the surface protective film of the present invention.
Fig. 3 is a cross-sectional view showing an embodiment of the optical member of the present invention.
Description of reference numerals
1 … … substrate film; 2 … … adhesive layer; 3 … … resin film; 4 … … a release agent layer;
5 … … peeling film; 7 … … an antistatic agent; 8 … … adherend (optical member);
10 … … surface protective film; 11 … … the surface protective film from which the release film has been peeled off;
20 … … an optical member having a surface protective film attached thereto.
Detailed Description
The present invention will be described in detail below based on embodiments.
Fig. 1 is a cross-sectional view showing the concept of the surface protective film of the present invention. The surface protection film 10 has an adhesive layer 2 formed on one surface of a transparent base film 1. A release film 5 is bonded to the surface of the adhesive layer 2, and the release film 5 is formed by forming a release agent layer 4 on the surface of the resin film 3.
As the base film 1 used for the surface protective film 10 of the present invention, a base film made of a resin having transparency and flexibility is used. Thus, the optical member can be subjected to appearance inspection in a state where the surface protective film is bonded to the optical member as an adherend. As the film made of a transparent resin used as the substrate film 1, a polyester film such as polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, or polybutylene terephthalate is preferably used. The base film may be a film made of other resins than the polyester film as long as it has a desired strength and optical compatibility. The substrate film 1 may be an unstretched film or a film subjected to uniaxial stretching or biaxial stretching. Further, the stretching magnification of the stretched film and the orientation angle in the axial direction of the stretched film, which is formed as the film is crystallized, may be controlled to specific values.
The thickness of the base film 1 used in the surface protective film 10 of the present invention is not particularly limited, and is preferably, for example, about 12 to 100 μm; a thickness of about 20 to 50 μm is more preferable because handling is easy.
Further, as necessary, an antifouling layer for preventing surface contamination, an antistatic layer, a hard coat layer for preventing scratches, and the like may be provided on the surface of the base material film 1 opposite to the surface on which the adhesive layer 2 is formed. The surface of the base film 1 may be subjected to an easy adhesion treatment such as surface modification by corona discharge or application of a primer.
The adhesive layer 2 used in the surface protective film 10 of the present invention is not particularly limited as long as it is an adhesive layer that can be adhered to the surface of an adherend, can be easily peeled off after use, and is less likely to contaminate the adherend, but an adhesive obtained by crosslinking a (meth) acrylate copolymer is generally used in consideration of durability after bonding to an optical film.
Examples of the (meth) acrylate ester copolymer include copolymers obtained by copolymerizing a main monomer, a comonomer, and a functional monomer, wherein the main monomer includes n-butyl acrylate, 2-ethylhexyl acrylate, isooctyl acrylate, isononyl acrylate, and the like; examples of the comonomer include acrylonitrile, vinyl acetate, methyl methacrylate, ethyl acrylate, etc.; examples of the functional monomer include acrylic acid, methacrylic acid, hydroxyethyl acrylate, hydroxybutyl acrylate, glycidyl methacrylate, and N-methylolmethacrylamide. In the (meth) acrylate copolymer, the main monomer and the other monomer may be (meth) acrylate, and one or two or more monomers other than (meth) acrylate may be contained as monomers other than the main monomer.
Further, the (meth) acrylate copolymer may be copolymerized or mixed with a polyoxyalkylene (polyoxakylene) -containing compound. Examples of the copolymerizable polyoxyalkylene group-containing compound include: polyethylene glycol (400) monoacrylate, polyethylene glycol (400) monomethacrylate, methoxypolyethylene glycol (400) acrylate, methoxypolyethylene glycol (400) methacrylate, polypropylene glycol (400) monoacrylate, polypropylene glycol (400) monomethacrylate, methoxypolypropylene glycol (400) acrylate, methoxypolypropylene glycol (400) methacrylate, and the like. By copolymerizing these polyoxyalkylene group-containing monomers with the main monomer and the functional monomer of the aforementioned (meth) acrylate copolymer, a binder composed of a polyoxyalkylene group-containing copolymer can be obtained.
The polyoxyalkylene group-containing compound miscible with the (meth) acrylate copolymer is preferably a polyoxyalkylene group-containing (meth) acrylate copolymer, more preferably a polymer of a polyoxyalkylene group-containing (meth) acrylic monomer, and examples thereof include polymers of polyethylene glycol (400) monoacrylate, polyethylene glycol (400) monomethacrylate, methoxypolyethylene glycol (400) acrylate, methoxypolyethylene glycol (400) methacrylate, polypropylene glycol (400) monoacrylate, polypropylene glycol (400) monomethacrylate, methoxypolypropylene glycol (400) acrylate, methoxypolypropylene glycol (400) methacrylate, and the like. By mixing these polyoxyalkylene group-containing compounds with the aforementioned (meth) acrylate copolymer, a binder to which a polyoxyalkylene group-containing compound is added can be obtained.
As the curing agent added to the adhesive layer 2, examples of the crosslinking agent for crosslinking the (meth) acrylate copolymer include isocyanate compounds, epoxy compounds, melamine compounds, metal chelates, and the like. Examples of the thickener include rosins, coumarone-indenes, terpenes, petroleum, phenols and the like.
The thickness of the adhesive layer 2 used in the surface protective film 10 of the present invention is not particularly limited, and is, for example, preferably about 5 to 40 μm, and more preferably about 10 to 30 μm. The adhesive layer 2 having a slight adhesive force with a peel strength (adhesive force) of the surface protective film to the adherend surface of about 0.03 to 0.3N/25mm is preferable because the workability in peeling the surface protective film from the adherend is excellent. Further, from the viewpoint of excellent workability when peeling the release film 5 from the surface protective film 10, the peeling force for peeling the release film 5 from the adhesive layer 2 is preferably 0.005 to 0.3N/50mm as measured under the conditions of a peeling speed of 0.3m/min and a peeling angle of 180 °.
The release film 5 used in the surface protection film 10 of the present invention is formed by laminating a release agent layer 4 on one surface of a resin film 3, and the release agent layer 4 contains a release agent mainly composed of a long-chain alkyl group-containing resin and an antistatic agent that does not react with the release agent.
Examples of the resin film 3 include a polyester film, a polyamide film, a polyethylene film, a polypropylene film, and a polyimide film, and the polyester film is particularly preferable from the viewpoint of excellent transparency and relatively low cost. The resin film may be an unstretched film, a uniaxially stretched film or a biaxially stretched film. Further, the stretching magnification of the stretched film and the orientation angle in the axial direction of the stretched film, which is formed as the film is crystallized, may be controlled to specific values.
The thickness of the resin film 3 is not particularly limited, and is preferably about 12 to 100 μm, for example; a thickness of about 20 to 50 μm is more preferable because handling is easy.
The surface of the resin film 3 may be subjected to an easy adhesion treatment such as surface modification by corona discharge or coating with a primer, if necessary.
Examples of the release agent containing a long-chain alkyl group-containing resin as a main component constituting the release agent layer 4 include: known long-chain alkyl group-containing releasing agents include long-chain alkyl group-containing aminoalkyd resins, long-chain alkyl group-containing acrylic resins, long-chain aliphatic side group-containing resins (reaction products between at least one active hydrogen-containing polymer selected from polyvinyl alcohol, ethylene/vinyl alcohol copolymers, polyethyleneimine and hydroxyl group-containing cellulose derivatives, and long-chain alkyl group-containing isocyanates). The releasing agent may be one that undergoes a curing reaction by adding a curing agent or an ultraviolet initiator, or one that undergoes curing by volatilizing a solvent.
The "long chain alkyl group" is preferably an alkyl group having 8 to 30 carbon atoms, and may have 10 or more, 12 or more, 18 or less, 24 or less carbon atoms, and among them, a linear alkyl group is preferable. Specific examples thereof include one or more alkyl groups selected from decyl, undecyl, lauroyl, dodecyl, tridecyl, myristyl, tetradecyl, pentadecyl, cetyl, palmityl, hexadecyl, heptadecyl, stearoyl, octadecyl, nonadecyl, eicosyl, docosyl and the like.
Examples of commercially available products of the long chain alkyl group-containing resin-based release agent include: ASHIO RESIN (アシオレジン, registered trademark) RA-30 manufactured by ASHIO co., LTD. (アシオ, LTD.); piroiru (ピーロイル, registered trademark) 1010, Piroiru 1010S, Piroiru1050, and Piroiru HT, manufactured by yokoku industries co; resem (レゼム) N-137, manufactured by Zhongjing grease Co., Ltd; exceparl (エキセパール, registered trade Mark) PS-MA manufactured by Kao corporation; tess Fine (テスファイン, registered trademark) 303 manufactured by Hitachi chemical Co., Ltd.
As the antistatic agent constituting the release agent layer 4, an antistatic agent which has good dispersibility in a release agent solution containing a long chain alkyl group-containing resin as a main component and does not inhibit curing of a release agent containing a long chain alkyl group-containing resin as a main component is preferable. In addition, in order to impart an antistatic effect to the adhesive layer by transferring from the release agent layer 4 to the surface of the adhesive layer 2, an antistatic agent that does not react with a release agent containing a long chain alkyl group-containing resin as a main component may be used. As such an antistatic agent, an alkali metal salt is preferred.
Examples of the alkali metal salt include: metal salts of lithium, sodium, potassium. Specifically, for example, a metal salt composed of a cation selected from Li and an anion is preferably used+、Na+、K+Wherein the anion is selected from Cl-、Br-、I-、BF4 -、PF6 -、SCN-、ClO4 -、CF3SO3 -、(FSO2)2N-、(CF3SO2)2N-、(C2F5SO2)2N-、(CF3SO2)3C-In (1). Among them, LiBr, LiI and LiBF are particularly preferably used4、LiPF6、LiSCN、LiClO4、LiCF3SO3、Li(FSO2)2N、Li(CF3SO2)2N、Li(C2F5SO2)2N、Li(CF3SO2)3C, lithium salts. These alkali metal salts may be used alone or in combination of two or more. For stabilization of the ionic substance, a compound having a polyoxyalkylene structure may be added.
The amount of the antistatic agent added to the release agent mainly composed of the long-chain alkyl group-containing resin varies depending on the kind of the antistatic agent and the degree of affinity with the release agent, and may be set in consideration of the electrostatic pressure required for releasing the surface protective film from the adherend, the staining property to the adherend, the adhesion property, and the like.
The method of mixing the release agent containing a long-chain alkyl group-containing resin as a main component and the antistatic agent constituting the release agent layer 4 is not particularly limited. Any of the following mixing methods may be employed: a method in which an antistatic agent is added to a release agent mainly composed of a long-chain alkyl group-containing resin, and the mixture is mixed, and then a catalyst for curing the release agent is added thereto; a method of diluting a release agent mainly composed of a long-chain alkyl group-containing resin with an organic solvent in advance, and then adding and mixing an antistatic agent and a release agent curing catalyst; a method in which a release agent mainly composed of a long chain alkyl group-containing resin is diluted with an organic solvent, a catalyst is added thereto, and the mixture is mixed, and then an antistatic agent is added thereto and mixed. Further, if necessary, an adhesion promoter such as a silane coupling agent, a material for assisting the antistatic effect such as a polyoxyalkylene group-containing compound, or the like may be added.
The mixing ratio of the release agent containing a long chain alkyl group-containing resin as a main component and the antistatic agent is not particularly limited, but the antistatic agent is preferably contained in an amount of about 5 to 100 in terms of solid content, based on 100 in terms of solid content of the release agent containing a long chain alkyl group-containing resin as a main component. If the amount of the antistatic agent added is less than 5 in terms of solid content relative to 100 in terms of solid content of the release agent mainly composed of a long-chain alkyl group-containing resin, the amount of transfer of the antistatic agent to the surface of the adhesive layer is also reduced, and it is difficult for the adhesive layer to exhibit an antistatic function. Further, if the amount of the antistatic agent added in terms of solid content exceeds 100 relative to the solid content 100 of the release agent mainly composed of the long-chain alkyl group-containing resin, the release agent mainly composed of the long-chain alkyl group-containing resin together with the antistatic agent is also transferred to the surface of the adhesive layer, and thus the adhesive properties of the adhesive layer are degraded.
In the present invention, the method of forming the adhesive layer 2 on the base film 1 of the surface protective film 10 and the method of bonding the release film 5 can be performed by any known method, and is not particularly limited. Specifically, there may be mentioned: (1) a method in which a resin composition for forming the adhesive layer 2 is applied to one surface of the base film 1, dried, formed into an adhesive layer, and then the release film 5 is attached; (2) a method in which the resin composition for forming the adhesive layer 2 is applied to the surface of the release film 5 and dried to form an adhesive layer, and then the base film 1 is laminated. Any of these methods may be employed.
In addition, when the adhesive layer 2 is formed on the surface of the base film 1, it can be performed by a known method. Specifically, a known coating method such as reverse coating, comma blade coating, gravure coating, slot die coating, Mayer bar coating, or air knife coating can be used.
Similarly, when the release agent layer 4 is formed on the resin film 3, it can be formed by a known method. Specifically, known coating methods such as gravure coating, mayer rod coating, and air knife coating can be used.
The surface protective film 10 of the present invention having the above-described configuration preferably has a surface potential of +0.7kV to-0.7 kV when peeled from an optical film as an adherend. Further, the surface potential is more preferably from +0.5kV to-0.5 kV, and particularly preferably from +0.3kV to-0.3 kV. The surface potential can be adjusted by changing the kind, amount, and the like of the antistatic agent contained in the release agent layer.
Fig. 2 is a sectional view showing a state where the release film is peeled off from the surface protective film of the present invention.
By peeling the release film 5 from the surface protection film 10 shown in fig. 1, a part of the antistatic agent (reference numeral 7) contained in the release agent layer 4 of the release film 5 is transferred (adhered) to the surface of the adhesive layer 2 of the surface protection film 10. Therefore, in fig. 2, the antistatic agent attached to the surface of the adhesive layer 2 of the surface protective film is schematically shown by a spot of reference numeral 7. The transfer of the antistatic agent 7 from the release film 5 to the surface of the adhesive layer 2 reduces the electrostatic peeling voltage when peeling the adhesive layer 2 from the adherend, as compared with the adhesive layer 2 before the transfer. The peeling static voltage at the time of peeling the adhesive layer from the adherend can be measured by a known method. For example, after a surface protective film is attached to an adherend such as a polarizing plate, the surface protective film is peeled off at a peeling speed of 40m per minute using a high speed peel TESTER (manufactured by TESTER industries co., Ltd.), and the surface potential of the adherend surface is measured every 10ms using a surface potentiometer (manufactured by keyence corporation), and the maximum value of the absolute value of the surface potential at this time is measured as a peeling static voltage (kV).
In the surface protective film of the present invention, when the surface protective film 11 shown in fig. 2 in a state where the release film is peeled off is attached to an adherend, the antistatic agent transferred to the surface of the adhesive layer 2 comes into contact with the adherend surface. By this operation, the peeling static voltage at the time of peeling the surface protective film from the adherend again can be suppressed to a low level.
Fig. 3 is a sectional view showing an embodiment of the optical member of the present invention.
The release film 5 is peeled off from the surface protective film 10 of the present invention, and the adhesive layer 2 is exposed, and then the optical member 8 as an adherend is bonded with the adhesive layer 2.
That is, fig. 3 shows the optical member 20 to which the surface protective film 10 of the present invention is bonded. Examples of the optical member include optical films such as a polarizing plate, a retardation plate, a lens film, a polarizing plate which also serves as a retardation plate, and a polarizing plate which also serves as a lens film. Such optical components are used as components of liquid crystal display devices such as liquid crystal display panels, and various optical system devices for measuring instruments. Further, as the optical member, there may be mentioned optical films such as an antireflection film, a hard coat film, and a transparent conductive film for a touch panel.
According to the optical member of the present invention, when the surface protective film 10 is peeled and removed from the optical member (optical film) as an adherend, the peeling static voltage can be sufficiently suppressed to a low level. Therefore, there is no fear that circuit components such as the driver IC, the TFT element, and the gate line driver circuit are broken, and the production efficiency in the process of manufacturing the liquid crystal display panel and the like can be improved, and the reliability of the production process can be ensured.
Examples
The present invention is further illustrated by the following examples.
(production of surface protective film)
(example 1)
3.125 parts by weight of a releasing agent containing a long-chain alkyl group-containing resin as a main component (product name "TessFine (テスファイン) 303", manufactured by Hitachi chemical Co., Ltd.), 10 parts by weight of a 10% ethyl acetate solution of lithium bis (fluorosulfonyl) imide, 96.875 parts by weight of toluene and ethyl acetate were 50: 50 parts by weight of a solvent mixture and 0.09 part by weight of a catalyst (product name "Dryer (ドライヤー) 900", manufactured by Hitachi chemical Co., Ltd.) were mixed together and stirred to prepare a coating material for forming the release agent layer of example 1. The coating material for a release agent layer of example 1 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 μm using a maller bar so that the thickness after drying became 0.2 μm, and dried in a hot air circulation type oven at 120 ℃ for 1 minute, to obtain a release film of example 1. On the other hand, 2-ethylhexyl acrylate and 2-hydroxyethyl acrylate were copolymerized at a weight ratio of 100:4, 30 parts by weight of an acrylate copolymer having a weight average molecular weight of 47 ten thousand was dissolved in 70 parts by weight of ethyl acetate to obtain a binder (ethyl acetate solution having a solid content of 30%), 1.2 parts by weight of an HDI-based curing agent (product name "Coronate (コロネート, registered trademark) HX", manufactured by Nippon Polyurethane Industry co., Ltd.) was added to 100 parts by weight of the binder to form a coating liquid, the coating liquid was applied to the surface of a 38 μm thick polyethylene terephthalate film so that the thickness after drying became 20 μm, then dried for 2 minutes by a hot air circulating oven at 100 ℃ to form an adhesive layer. Then, the release agent layer (release agent treated surface) of the release film of example 1 produced above was bonded to the surface of the adhesive layer. The obtained adhesive film was kept at 40 ℃ for 5 days to cure the adhesive, thereby obtaining a surface protective film of example 1.
(example 2)
8.33 parts by weight of a releasing agent containing a long-chain alkyl group-containing resin as a main component (product name "Piroiru (ピーロイル) HT", manufactured by Okagaku industries Co., Ltd.), 10 parts by weight of a 10% ethyl acetate solution of lithium bis (trifluoromethanesulfonyl) imide, 91.67 parts by weight of toluene and ethyl acetate were 50: 50 were mixed together and stirred to prepare a coating material for forming the release agent layer of example 2. The coating material for a release agent layer of example 2 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 μm using a maller bar so that the thickness after drying became 0.2 μm, and dried in a hot air circulation type oven at 120 ℃ for 1 minute, to obtain a release film of example 2. The same operation as in example 1 was carried out except that the release film of example 2 was used instead of the release film of example 1, to obtain a protective film of example 2.
(example 3)
A stripping agent (product name "Piroiru 1010S", manufactured by oil and fat industries, ltd.) containing a long-chain alkyl group-containing resin as a main component in an amount of 1.5 parts by weight, a 10% ethyl acetate solution of lithium bis (fluorosulfonyl) imide in an amount of 10 parts by weight, and a solution of toluene, ethyl acetate and isopropyl alcohol in an amount of 98.5 parts by weight were set to 50: 40: the mixed solvents of 10 were mixed together and stirred to prepare a coating material for forming the release agent layer of example 3. The coating material for a release agent layer of example 3 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 μm using a maller bar so that the thickness after drying became 0.2 μm, and dried in a hot air circulation type oven at 120 ℃ for 1 minute, to obtain a release film of example 2. The same operation as in example 1 was carried out except that the release film of example 3 was used instead of the release film of example 1, to obtain a protective film of example 3.
Comparative example 1
3.125 parts by weight of a releasing agent (product name "TessFine 303", manufactured by Hitachi chemical Co., Ltd.) containing a long chain alkyl group-containing resin as a main component, 96.875 parts by weight of toluene and ethyl acetate were mixed to prepare 50: 50 parts by weight of a solvent mixture and 0.09 part by weight of a catalyst (product name "Dryer (ドライヤー) 900", manufactured by Hitachi chemical Co., Ltd.) were mixed together and stirred to prepare a coating material for forming the release agent layer of comparative example 1. The coating material for a release agent layer of comparative example 1 was applied to the surface of a polyethylene terephthalate film having a thickness of 38 μm using a maller bar so that the thickness after drying became 0.2 μm, and dried in a hot air circulation type oven at 120 ℃ for 1 minute, to obtain a release film of example 1. On the other hand, 5 parts by weight of a 10% ethyl acetate solution of lithium bis (fluorosulfonyl) imide and 1.2 parts by weight of an HDI-based curing agent (product name "Coronate (コロネート, registered trademark) HX", manufactured by nippon polyurethane Industry co., Ltd.) were added and mixed to 100 parts by weight of the adhesive of example 1 (an ethyl acetate solution having a solid content of 30%) to form a coating liquid, and the coating liquid was applied to the surface of a 38 μm thick polyethylene terephthalate film so that the dried thickness became 20 μm, and then dried in a hot air oven at 100 ℃ for 2 minutes, thereby forming a circulating adhesive layer. Then, the release agent layer (silicone-treated surface) of the release film of comparative example 1 produced above was bonded to the surface of the adhesive layer. The obtained adhesive film was kept at 40 ℃ for 5 days to cure the adhesive, thereby obtaining a surface protective film of comparative example 1.
Comparative example 2
A surface protective film of comparative example 2 was obtained in the same manner as in example 3, except that lithium bis (fluorosulfonyl) imide was not added to the release agent layer.
The method and results of the evaluation test are shown below.
Method for measuring surface resistivity of release agent layer and adhesive layer
The surface resistivity of the release agent layer of the release film and the surface resistivity of the adhesive layer of the surface protective film were measured under the conditions of an applied voltage of 100V and a measurement time of 30 seconds using Hiresta (ハイレスタ, registered trademark) -UP manufactured by mitsubishi chemical corporation. In the measurement, the surface resistivity a of the release agent layer of each of the samples aged by keeping the release film alone (release film monomer) at 40 ℃ for 5 days was measured; the surface resistivity B of the adhesive layer of the surface protective film and the surface resistivity C of the release agent layer of the release film obtained by peeling the release film from the surface protective films (surface protective films obtained by insulating the adhesive film to which the adhesive layer and the release agent layer are bonded at 40 ℃ for 5 days to cure the adhesive) of the examples and comparative examples.
Method for measuring peeling force of peeling film
A sample of the surface protective film was cut in a size of 50mm in width and 150mm in length. The strength of the release film was measured by peeling the release film in a 180 ° direction at a peeling rate of 300 mm/min using a tensile tester under a test environment of 23 ℃ x 50% RH, and the strength was determined as the peeling force (N/50mm) of the release film.
Method for measuring adhesive force of surface protective film
An antiglare low-reflection processed polarizing plate (AG-LR polarizing plate) was laminated on the surface of the glass plate by a laminator. Then, the surface protective film cut to a width of 25mm was attached to the surface of the polarizing plate, and then stored in a test environment at 23 ℃ x 50% RH for 1 day. Then, the surface protective film was peeled off in a 180 ° direction at a peeling speed of 300 mm/min using a tensile tester, and the strength at that time was measured and used as the adhesive force (N/25 mm).
Method for measuring electrostatic voltage for peeling surface protective film
An antiglare low-reflection processed polarizing plate (AG-LR polarizing plate) was laminated on the surface of the glass plate by a laminator. Then, the surface protective film cut to a width of 25mm was attached to the surface of the polarizing plate, and then stored in a test environment at 23 ℃ x 50% RH for 1 day. Then, the surface potential of the surface of the polarizing plate was measured every 10ms using a surface potentiometer (manufactured by Keyence Corporation) while peeling the surface protective film at a peeling speed of 40m per minute using a high speed peel TESTER (manufactured by TESTER industries co., Ltd.), and the maximum value of the absolute value of the surface potential at this time was taken as a peeling electrostatic voltage (kV).
Method for confirming surface contamination of surface protective film
A polarizing plate (AG-LR polarizing plate) subjected to anti-glare low-reflection treatment was attached to the surface of a glass plate by a laminator, a surface protective film cut to a width of 25mm was attached to the surface of the polarizing plate, and the polarizing plate was stored in a test environment at 23 ℃ C.. times.50% RH for 3 days and 30 days.
The obtained surface protective films of examples 1 to 3 and comparative examples 1 to 2 were measured, and the measurement results are shown in table 1. Wherein "2 EHA" means 2-ethylhexyl acrylate, "HEA" means 2-hydroxyethyl acrylate, "LiFSI" means lithium bis (fluorosulfonyl) imide, "LiTFSI" means lithium bis (trifluoromethanesulfonyl) imide, "303" means Tess Fine 303, "Dryer" means Dryer 900, "HT" means Piroiru HT を, "1010S" means Piroiru 1010S.
The surface resistivity a is the surface resistivity (Ω/□) of the release agent surface of the release film after aging of the release film alone (release film monomer), the surface resistivity B is the surface resistivity (Ω/□) of the adhesive surface of the surface protective film after peeling the release film from the surface protective film, and the surface resistivity C is the surface resistivity (Ω/□) of the release agent surface of the release film after peeling from the adhesive surface, respectively. In the table, OR is a abbreviation for "Over Range" and means that OR is out of the measurement Range of the surface resistance meter (Hiresta (ハイレスタ) -UP), and means that the surface resistivity is 1E + 13. omega./□ OR more. The value of the surface resistivity is expressed by an index method defined in JIS X0210. For example, 3.9E +8 refers to the 8 th power of 3.9 × 10.
TABLE 1
From the measurement results shown in table 1, the following was found.
The surface protective films of examples 1 to 3 of the present invention had appropriate adhesive force, did not contaminate the surface of the adherend, and had low peel static voltage when the surface protective film was peeled from the adherend. The surface resistivity of the release agent layer of the release film is 8.4E +7 to 3.9E +8 Ω/□ when the release film (release film alone) is used alone, but the surface resistivity of the release agent layer of the release film after being bonded to the adhesive surface and being peeled exceeds the rated range (1.0E +13 Ω/□ or more), and the surface resistivity of the adhesive surface is reduced to 3.7E +10 to 5.9E +10 Ω/□. From this, it was found that the antistatic agent had moved from the release agent surface to the adhesive surface.
On the other hand, the surface protective film of comparative example 1 in which the antistatic agent was added to the adhesive layer was good at low peeling static voltage when the surface protective film was peeled from the adherend, but contaminated with the adherend after peeling was much. In comparative example 2 in which no antistatic agent was used, although the staining property to the adherend was improved, the peeling electrostatic pressure when the surface protective film was peeled from the adherend was high.
Industrial applicability
The surface protective film of the present invention can be applied to optical films such as a polarizing plate, a retardation plate, and a lens film, and is bonded to various optical members and the like in production processes of the optical members and the like to protect the surfaces thereof. The surface protective film of the present invention can reduce the amount of static electricity generated when peeled from an adherend, has no change in antistatic performance over time (does not change over time), causes little contamination of the adherend, can improve the yield of production processes, and has a high industrial value.
Claims (5)
1. A surface protection film comprising a base film made of a transparent resin, an adhesive layer formed on one surface of the base film, and a release film having a release agent layer laminated on the adhesive layer, wherein,
the release film is formed by laminating a release agent layer on one surface of a resin film, wherein the release agent layer contains a release agent containing a resin containing a long-chain alkyl group as a main component and an antistatic agent which does not react with the release agent,
the antistatic agent is an alkali metal salt, and contains 5 to 100 parts by weight of the antistatic agent in terms of solid content per 100 parts by weight of solid content of a stripping agent mainly composed of a long-chain alkyl group-containing resin,
the antistatic agent component is transferred from the release film to the surface of the adhesive layer, so that the release electrostatic voltage when the adhesive layer is released from an adherend is reduced, and the antistatic agent is not contained in the adhesive layer.
2. The surface protective film according to claim 1, wherein the adhesive layer is obtained by crosslinking a (meth) acrylate copolymer.
3. The surface protective film according to claim 1 or 2, wherein the surface potential at the time of peeling from the optical film as an adherend is from +0.7kV to-0.7 kV.
4. The surface protective film according to claim 1 or 2, wherein a peeling force of the peeling film at the time of peeling from the adhesive layer is 0.005 to 0.3N/50 mm.
5. An optical member to which the surface protective film according to any one of claims 1 to 4 is bonded.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2014-171626 | 2014-08-26 | ||
| JP2014171626A JP6224547B2 (en) | 2014-08-26 | 2014-08-26 | Surface protective film and optical component on which it is bonded |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN105385370A CN105385370A (en) | 2016-03-09 |
| CN105385370B true CN105385370B (en) | 2020-06-19 |
Family
ID=55418168
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201510397287.0A Active CN105385370B (en) | 2014-08-26 | 2015-07-08 | Surface protection film and optical component bonded with same |
Country Status (4)
| Country | Link |
|---|---|
| JP (1) | JP6224547B2 (en) |
| KR (2) | KR101891974B1 (en) |
| CN (1) | CN105385370B (en) |
| TW (2) | TWI726330B (en) |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP6500821B2 (en) * | 2016-03-19 | 2019-04-17 | 三菱ケミカル株式会社 | Laminated film |
| JP6471712B2 (en) * | 2016-03-19 | 2019-02-20 | 三菱ケミカル株式会社 | Laminated film |
| CN109476960A (en) * | 2016-07-28 | 2019-03-15 | 日东电工株式会社 | Enhancing film with isolation film |
| JP6997976B2 (en) * | 2017-10-13 | 2022-01-18 | 東レフィルム加工株式会社 | Release film for epoxy resin-containing layer transfer film and epoxy resin-containing layer transfer film |
| JP7400467B2 (en) * | 2018-03-29 | 2023-12-19 | 東洋紡株式会社 | Antifouling film with protective film and its manufacturing method |
| CN111440556B (en) * | 2019-09-29 | 2022-02-22 | 宁波激智科技股份有限公司 | Protective film and preparation method thereof |
Family Cites Families (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH1044336A (en) * | 1996-08-08 | 1998-02-17 | Toray Ind Inc | Mold releasing film |
| JP2000290610A (en) * | 1999-04-07 | 2000-10-17 | Nitto Denko Corp | Long-chain alkyl-based releasing agent, its production, separator, and tacky adhesive sheet subjected to back releasing treatment |
| JP2002019039A (en) * | 2000-07-11 | 2002-01-22 | Nitto Denko Corp | Protective film for protecting surface of optical member |
| JP4170102B2 (en) * | 2003-01-23 | 2008-10-22 | 藤森工業株式会社 | Surface protective film and laminate using the same |
| JP4279118B2 (en) | 2003-10-30 | 2009-06-17 | 藤森工業株式会社 | Surface protective film and optical component on which it is adhered |
| JP3912686B2 (en) | 2004-04-19 | 2007-05-09 | 日東電工株式会社 | Adhesive composition, adhesive layer, and surface protective film |
| JP2005314476A (en) | 2004-04-27 | 2005-11-10 | Nitto Denko Corp | Adhesive composition, adhesive sheet and surface-protective film |
| JP4799900B2 (en) | 2004-10-28 | 2011-10-26 | 日東電工株式会社 | Adhesive composition, adhesive sheet and surface protective film |
| JP4771082B2 (en) * | 2006-08-23 | 2011-09-14 | アキレス株式会社 | Antistatic release film |
| JP2008075072A (en) * | 2006-08-24 | 2008-04-03 | Diatex Co Ltd | Easily peelbale adhesive sheet and its production method |
| JP5130768B2 (en) * | 2007-03-30 | 2013-01-30 | 大日本印刷株式会社 | Protective film for optical member, method for producing protective film for optical member, and protective film raw material for optical member |
| JP5587645B2 (en) * | 2010-03-18 | 2014-09-10 | リンテック株式会社 | Optical pressure-sensitive adhesive, optical pressure-sensitive adhesive sheet, and optical member with a pressure-sensitive adhesive layer |
| JP2011252948A (en) * | 2010-05-31 | 2011-12-15 | Nitto Denko Corp | Antistatic adhesive optical film and image display device |
| JP5826105B2 (en) * | 2012-05-02 | 2015-12-02 | 藤森工業株式会社 | Surface protective film and optical component on which it is bonded |
| JP5977582B2 (en) * | 2012-05-25 | 2016-08-24 | 藤森工業株式会社 | Surface protective film and optical component on which it is bonded |
| JP5658711B2 (en) * | 2012-05-25 | 2015-01-28 | 藤森工業株式会社 | Release film for adhesive film and adhesive film using the same |
-
2014
- 2014-08-26 JP JP2014171626A patent/JP6224547B2/en active Active
-
2015
- 2015-07-06 KR KR1020150095895A patent/KR101891974B1/en active IP Right Grant
- 2015-07-08 CN CN201510397287.0A patent/CN105385370B/en active Active
- 2015-07-16 TW TW108119690A patent/TWI726330B/en active
- 2015-07-16 TW TW104123042A patent/TWI665086B/en active
-
2018
- 2018-08-21 KR KR1020180097126A patent/KR101981503B1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| KR101891974B1 (en) | 2018-08-27 |
| TWI726330B (en) | 2021-05-01 |
| TW201612010A (en) | 2016-04-01 |
| JP6224547B2 (en) | 2017-11-01 |
| TW201936397A (en) | 2019-09-16 |
| JP2016044283A (en) | 2016-04-04 |
| CN105385370A (en) | 2016-03-09 |
| KR20180095791A (en) | 2018-08-28 |
| KR101981503B1 (en) | 2019-05-23 |
| KR20160024742A (en) | 2016-03-07 |
| TWI665086B (en) | 2019-07-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI622495B (en) | Surface protection film and optical component attached with the same | |
| CN105385370B (en) | Surface protection film and optical component bonded with same | |
| TWI532804B (en) | Surface protection film and optical component attached with the same | |
| TWI527694B (en) | Surface protection film and optical component attached with the same | |
| CN105331296B (en) | Surface protection film and optical component bonded with same | |
| CN106189894B (en) | Surface protection film and optical component bonded with same | |
| CN107083197B (en) | Surface protection film and optical component bonded with same | |
| CN106010322B (en) | Antistatic surface protective film | |
| KR101968924B1 (en) | Release film for antistatic surface-protective film | |
| KR101989305B1 (en) | Surface-protective film and optical component attached with the same | |
| CN106675427B (en) | Surface protection film and optical component bonded with same | |
| CN106520000B (en) | Surface protection film and optical component bonded with same | |
| JP6403354B2 (en) | Release film for surface protection film | |
| JP2018118513A (en) | Release film for antistatic surface protective film, and antistatic surface protective film laminated with the same for optical film | |
| JP7362882B2 (en) | Antistatic surface protection film | |
| JP6233993B2 (en) | Release film for antistatic surface protective film, and antistatic surface protective film | |
| JP2016083941A (en) | Release film for antistatic surface protective film, and antistatic surface protective film |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |