JP6222816B2 - Surface protection film for chemical polishing treatment - Google Patents

Description

The present invention relates to an adhesive film and a surface protective film. More specifically, the present invention is a surface protective film used for a glass substrate chemical polishing step, etc., which is formed on an adherend glass substrate, an ITO surface for a touch panel sensor, or the opposite side thereof. The surface protective film for chemical polishing treatment that can be used for protecting the adherend by being attached to the surface of the substrate is provided.

  Conventionally, for the purpose of reducing the thickness of a glass substrate or the like, it is known that after a surface protective film is bonded to one surface of a glass substrate or the like, the other surface is chemically polished using an etching solution. (For example, see Patent Documents 1 and 2).

  Patent Document 1 states that “the conventional chemical polishing method uses strong acid hydrofluoric acid as an etching solution, so that the masking layer is eroded during etching or peels off from a glass substrate (LCD glass substrate, etc.). In order to solve the problem, on the other side of the glass substrate, a coating layer having high chemical resistance and adhesion is formed on the surface of the glass substrate for protection. A method is shown in which the coating layer is peeled and removed after being thinned by etching. In order to protect one surface during etching, it is necessary to use a coating layer having a sufficiently strong adhesive force. However, when the coating layer is peeled off from a thinned substrate or the like, there is a crack in the glass substrate. May occur. For this reason, the method disclosed in Patent Document 1 has a problem that it is difficult to peel the coating layer from the glass substrate or the like after being thinned.

  Further, in Patent Document 2, when etching a printed wiring board made of metal, glass, ceramic, plastic, etc., or a plate-like board made of other crystalline brittle materials, etc., it is bonded to the non-etched surface, A releasable pressure-sensitive adhesive tape used for masking during an etching process is disclosed. In the invention described in Patent Document 2, the pressure-sensitive adhesive layer is composed of a (meth) acrylic resin composition that does not substantially contain a hydrophilic carboxyl group, thereby allowing an etching solution such as acid or alkali to enter. Suppressed. As a result, erosion of the non-etched surface by the etching solution can be suppressed, and the adhesive layer can be easily peeled off without cohesive failure after completion of etching. However, the etching resistance was “a 25 mm square adhesive tape sample was bonded to the mirror surface side of a 6-inch silicon wafer, and left for 1 hour, and then immersed in a 10 wt% NaOH aqueous solution at 70 ° C. for 20 minutes. In the case where the intrusion of the etching solution was not confirmed, the invasion of the etching solution was confirmed in the immersion for 10 minutes or more and less than 20 minutes, and the invasion of the etching solution was confirmed in the immersion for less than 10 minutes. The product was ranked as x. ”, And the etching resistance to an etching solution containing a hydrofluoric acid aqueous solution as a main component for chemically polishing a glass substrate was insufficient.

  The conventional touch panel has a structure in which an ITO glass (film) layer is laminated in two layers under a cover glass. Later, due to the trend of simplified structure and thinner film, the demand for OGS (one glass solution) panels with a single glass substrate and touch sensor layers on both surfaces of the glass substrate has increased recently. (For example, see Non-Patent Documents 1 and 2).

JP 2004-182586 A JP 2009-209223 A

Nihon Keizai Shimbun, “Japan NanoOpt develops a touch glass integrated touch panel”, [online], May 18, 2012, Internet <http: // www. nikkei. com / article / DGXNASFK1703Y_X10C12A5000000 /> "Is the next iPad mini display using touch panel / cover glass integrated technology?", [Online], January 10, 2013, Internet <http: // taisy0. com / 2013/01/10/13280. html>

  In the case of an OGS panel, a touch sensor layer is provided on both surfaces of a large-sized glass substrate and then cut into a size of a small panel such as a smartphone. In order to remove the burrs on the end face of the cut glass substrate and make it smooth, a chemical polishing process is performed using an etching solution whose main component is hydrofluoric acid. A hydrofluoric acid resistant protective sheet is used to protect both surfaces of the glass substrate during the chemical polishing process. However, the conventional hydrofluoric acid-resistant protective sheet has a problem that even if the intrusion of hydrofluoric acid is prevented, the adhesive surface contaminates the panel surface after the hydrofluoric acid-resistant protective sheet is peeled off. . To date, there has been no hydrofluoric acid-resistant protective sheet that not only prevents entry of hydrofluoric acid but also does not cause adhesive residue.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a surface protection film for chemical polishing treatment that not only prevents entry of an etching solution but also does not cause adhesive residue on an adherend. .

  In the present invention, a resin film having a thickness of 75 μm or more is used as a base material, and an alkyl (meth) acrylate monomer having a C1-C14 alkyl group, at least one of a hydroxyl group-containing vinyl monomer and a nitrogen-containing vinyl monomer. A pressure-sensitive adhesive layer is formed of a pressure-sensitive adhesive composition containing an acrylic copolymer containing a copolymerizable vinyl monomer. In addition, this pressure-sensitive adhesive layer does not contain a carboxyl group-containing monomer (avoids containing a carboxyl group-containing monomer and prevents the ITO layer in contact with the pressure-sensitive adhesive layer from corroding), and further uses a silane coupling agent in combination. As a result, water repellency was added and the problems of the prior art were solved.

That is, the present invention is a chemical polishing treatment surface protective film having a pressure-sensitive adhesive layer on one side of a resin film substrate, wherein the resin film substrate has a thickness of 75 μm or more, and the pressure-sensitive adhesive layer is ( a) the number of carbon atoms in the alkyl group is an alkyl of C1 to C14 (meth) acrylate monomer, and (B) at least one or more copolymerizable vinyl monomer selected from the group of a hydroxyl group-containing vinyl monomers and nitrogen-containing vinyl monomer And a pressure-sensitive adhesive composition comprising an acrylic copolymer copolymerized without containing a carboxyl group-containing monomer , (C) a silane coupling agent, and (D) a crosslinking agent. becomes, at least the silane coupling agent, an epoxy group, selected from the group consisting of (meth) acryloxy group, a mercapto group, an amino group A kind, an organic functional group, the adhesive layer has a thickness made by laminating at 10 to 35 [mu] m, when the thickness of the adhesive layer is 20 [mu] m, the adhesive strength for a glass plate 0.1 Provided is a surface protective film for chemical polishing , characterized by being 5 N / 25 mm.

  The pressure-sensitive adhesive layer comprises (A) 80 to 95 parts by weight of at least one alkyl (meth) acrylate monomer having an alkyl group with C1 to C14, and (B) a hydroxyl group-containing vinyl monomer and a nitrogen-containing vinyl monomer. 100 parts by weight of an acrylic copolymer containing 5 to 20 parts by weight of at least one copolymerizable vinyl monomer selected from the group of (C), and 0.01 to 1 part by weight of (C) a silane coupling agent And (D) a pressure-sensitive adhesive composition containing 0.01 to 10 parts by weight of a crosslinking agent.

  It is preferable that the silane coupling agent has at least one organic functional group selected from the group consisting of an epoxy group, a (meth) acryloxy group, a mercapto group, and an amino group.

  The crosslinking agent is preferably an isocyanate compound.

Moreover, this invention provides the surface protection film for touchscreens using the said surface protection film for chemical polishing processes .

Moreover, this invention provides the surface protection film for optical members using the said surface protection film for chemical polishing processes .

According to the present invention, it is possible to provide a surface protection film for chemical polishing treatment that not only prevents intrusion of hydrofluoric acid but also has no problems such as adhesive residue.

It is the figure which showed the test method of the erodibility from the edge part of a glass plate. It is a graph which shows the relationship between the erosion time and the erosion distance of Example 1 and Comparative Example 1.

Hereinafter, the present invention will be described based on preferred embodiments.
The present invention is a pressure-sensitive adhesive film that is used in a chemical polishing process or the like for manufacturing a panel structure (OGS) of a single-glass glass with a simplified structure in accordance with the increasing demand for touch panels in recent years. I will provide a. The present invention protects the panel surface (for example, ITO surface) from an etching solution during a chemical polishing process in which the panel end face is treated with hydrofluoric acid (which may be mixed with a strong acid such as sulfuric acid). The present invention relates to an adhesive film that can be used as a sheet.
The conventional hydrofluoric acid-resistant protective sheet has not been able to sufficiently protect the panel surface due to permeation of hydrofluoric acid. Moreover, even if the surface of the panel could be protected, when peeled off after the chemical polishing process, there is a phenomenon such as the adhesive of the hydrofluoric acid resistant protective sheet contaminating the panel, and the removability is not good. The performance was not satisfactory.

  As for the adhesive film of this invention, the adhesive layer is formed in the single side | surface of the resin film base material. And this adhesive film is laminated | stacked by the thickness of the said adhesive layer being 10-35 micrometers, and when the thickness of the said adhesive layer is 20 micrometers, the adhesive force with respect to a glass plate is 0.1-1.5N / 25mm. It is characterized by being. The adhesive film is an adherend after being immersed in a hydrofluoric acid aqueous solution having a temperature of 27 ° C. and a concentration of 15% in a state where the adhesive film is bonded to a glass plate via the adhesive layer. It is possible to prevent permeation of hydrofluoric acid on the adherend surface of the glass plate for at least 150 seconds.

  In the present invention, the resin film substrate has a thickness of 75 μm or more, (A) an alkyl group having a C1-C14 alkyl (meth) acrylate monomer, (B) a hydroxyl group-containing vinyl monomer and nitrogen-containing material. A pressure-sensitive adhesive composition containing an acrylic copolymer containing at least one copolymerizable vinyl monomer selected from the group of vinyl monomers, (C) a silane coupling agent, and (D) a crosslinking agent. An adhesive layer is formed. In addition, this pressure-sensitive adhesive layer does not contain a carboxyl group-containing monomer (the purpose is to prevent the ITO layer in contact with the pressure-sensitive adhesive layer from corroding by containing a carboxyl group-containing monomer), and also adds water repellency Therefore, it is preferable to use a silane coupling agent in combination.

  In the pressure-sensitive adhesive film of the present invention, the pressure-sensitive adhesive composition used for forming the pressure-sensitive adhesive layer is preferably composed of the following blending ratio. That is, (A) the number of carbon atoms of the alkyl group is selected from the group of 80 to 95 parts by weight of at least one alkyl (meth) acrylate monomer having C1 to C14, and (B) a hydroxyl group-containing vinyl monomer and a nitrogen-containing vinyl monomer. 100 parts by weight of an acrylic copolymer containing 5 to 20 parts by weight of at least one copolymerizable vinyl monomer, 0.01 to 1 part by weight of (C) a silane coupling agent, and (D ) A pressure-sensitive adhesive composition containing 0.01 to 10 parts by weight of a crosslinking agent.

  (A) Examples of the acrylate monomer having an alkyl group with a C1 to C14 carbon number include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, and isobutyl (meth) ) Acrylate, pentyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, isononyl (meth) ) Acrylate, decyl (meth) acrylate, cyclopentyl (meth) acrylate, cyclohexyl (meth) acrylate, and the like. The alkyl group of the acrylate monomer may be linear, branched or cyclic.

(B) The hydroxyl group-containing vinyl monomer and the nitrogen-containing vinyl monomer are selected from (A) monomers that are copolymerizable with an alkyl (meth) acrylate monomer having an alkyl group with C1 to C14.
Examples of the hydroxyl group-containing vinyl monomer (B) include hydroxyl groups such as 8-hydroxyoctyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, and hydroxyethyl (meth) acrylate. Examples thereof include hydroxyl group-containing (meth) acrylamides such as group-containing (meth) acrylic acid esters, N-hydroxy (meth) acrylamide, N-hydroxymethyl (meth) acrylamide, and N-hydroxyethyl (meth) acrylamide.

  Examples of the nitrogen-containing vinyl monomer (B) include cyclic nitrogen vinyl compounds such as N-vinylpyrrolidone, N-vinylcaprolactam and acryloylmorpholine, N-ethyl-N-methyl (meth) acrylamide, N-methyl-N- Propyl (meth) acrylamide, N-methyl-N-isopropyl (meth) acrylamide, N, N-dimethyl (meth) acrylamide, N, N-diethyl (meth) acrylamide, N, N-dipropyl (meth) acrylamide, N, Dialkyl-substituted acrylamides such as N-diisopropyl (meth) acrylamide, N, N-dibutyl (meth) acrylamide, N-ethyl-N-methylaminoethyl (meth) acrylate, N-methyl-N-propylaminoethyl (meth) acrylate N-methyl-N-i Propylaminoethyl (meth) acrylate, N, N-dimethylaminomethyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-dimethylaminobutyl (meth) acrylate, N, N-dimethylamino Propyl (meth) acrylate, N, N-dipropylaminoethyl (meth) acrylate, dialkylamino acrylate such as N, N-dibutylaminoethyl (meth) acrylate, N-ethyl-N-methylaminopropyl (meth) acrylamide, N-methyl-N-propylaminopropyl (meth) acrylamide, N-methyl-N-isopropylaminopropyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide, N, N-diethylaminopropyl (meth) acrylic Ruamido, N, dialkyl-substituted amino propyl (meth) acrylamide such as N- dipropylamino-propyl (meth) acrylamide. The nitrogen-containing vinyl monomer (B) may contain a hydroxyl group (for example, the hydroxyl group-containing (meth) acrylamide described above). In that case, the nitrogen-containing vinyl monomer is classified as a hydroxyl group-containing vinyl monomer. .

(C) As a silane coupling agent, at least one organic functional group and at least one hydrolyzable group are contained in one molecule, and the hydrolyzable group is an alkoxy group bonded to a silicon atom, or the like. There are certain compounds. It is preferable that the silane coupling agent has at least one organic functional group selected from the group consisting of an epoxy group, a (meth) acryloxy group, a mercapto group, and an amino group. Here, the (meth) acryloxy group means an acryloxy group (CH ₂ ═CHCOO—) or a methacryloxy group (CH ₂ ═C (CH ₃ ) COO—).

Examples of the silane coupling agent having an epoxy group include 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, and 3-glycidoxypropyl. Triethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltrimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) ethylmethyldiethoxysilane, 2- (3,4-epoxycyclohexyl) ethyltriethoxysilane, 5,6-epoxyhexyltrimethoxysilane, 5,6-epoxyhexylmethyldimethoxysilane, 5,6-epoxyhexylmethyldiethoxysilane, 5,6- Epoxy hex Such as triethoxy silane.
Examples of the silane coupling agent having a (meth) acryloxy group include 3- (meth) acryloxypropyltrimethoxysilane, 3- (meth) acryloxypropylmethyldimethoxysilane, and 3- (meth) acryloxypropyltriethoxy. Examples thereof include silane, 3- (meth) acryloxypropylmethyldiethoxysilane, 3- (meth) acryloxypropyldimethylethoxysilane, and 3- (meth) acryloxypropyldimethylmethoxysilane.
Examples of the silane coupling agent having a mercapto group include 3-mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltrimethoxysilane, 3-mercaptopropylmethyldiethoxysilane, and 3-mercaptopropyltriethoxysilane.
Examples of the silane coupling agent having an amino group include 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, N-phenyl-3-aminopropyltrimethoxysilane, N-2- (aminoethyl)- 3-aminopropylmethyldimethoxysilane, N-2- (aminoethyl) -3-aminopropylmethyldiethoxysilane, N-2- (aminoethyl) -3-aminopropyltrimethoxysilane, N-2- (aminoethyl) ) -3-aminopropyltriethoxysilane, 3- (methylamino) propyltrimethoxysilane, 3- (methylamino) propyltriethoxysilane and the like.
Moreover, the oligomerized alkoxy oligomer (silicone alkoxy oligomer) containing the said organic functional group etc. can also be used as a silane coupling agent.

(D) As a crosslinking agent, it is 1 or more types of crosslinking selected from the compound group which consists of bifunctional or more isocyanate type crosslinking agent (isocyanate compound), bifunctional or more epoxy type crosslinking agent, and aluminum chelate type crosslinking agent. It is preferable that it is an agent. A crosslinking agent may be used individually by 1 type, and may be used together in combination of 2 or more types.
Examples of the crosslinking agent for the isocyanate compound include diisocyanates such as hexamethylene diisocyanate (HDI), isophorone diisocyanate, diphenylmethane diisocyanate, tolylene diisocyanate (TDI), xylylene diisocyanate (XDI), and burette modified products and isocyanurates of the diisocyanate. Examples thereof include polyisocyanate compounds such as modified products, trimethylolpropane, and adducts with trivalent or higher polyols such as glycerin.

  The pressure-sensitive adhesive composition may further contain known additives such as an antioxidant and an antistatic agent as other components. These may be used alone or in combination of two or more.

The adhesive film of this invention can be manufactured by forming the adhesive layer which consists of the said adhesive composition in the single side | surface of a resin film base material. Moreover, in order to protect the adhesive surface of an adhesive layer, a release film (separator) can be laminated | stacked.
As the resin film substrate used for the adhesive film of the present invention, various resin films such as polyolefin films such as polyethylene and polypropylene, polyester films such as polyethylene terephthalate, polyethylene naphthalate, polyethylene isophthalate, and polybutylene terephthalate are used. Can be used. As the resin film substrate, a polyester film having a thickness of 75 μm or more is preferable because the film has high rigidity and is difficult to be deformed. When the thickness of the resin film substrate is less than 75 μm, the rigidity is low and the resin film substrate is easily deformed. As a result, the adhesive film is bonded to the glass plate as the adherend through the adhesive layer. Since hydrofluoric acid easily permeates between the agent layer and the glass plate, it is not preferable.

  The pressure-sensitive adhesive layer is preferably laminated with a thickness of 10 to 35 μm. Moreover, it is preferable that the adhesive force with respect to the said glass plate is 0.1-1.5N / 25mm when the thickness of the said adhesive layer is 20 micrometers. If the adhesive strength of the resin film substrate is greater than 1.5 N / 25 mm, an adhesive residue is generated when the adhesive film is bonded to the glass plate as an adherend via the adhesive layer and then peeled off. Since it becomes easy, it is not preferable. When the adhesive strength of the resin film substrate is less than 0.1 N / 25 mm, the adhesive layer and the glass are bonded to the glass plate as the adherend through the adhesive layer. Since hydrofluoric acid easily penetrates between the plates, it is not preferable. When the thickness of the pressure-sensitive adhesive layer is not 20 μm, the preferable numerical range of the adhesive force to the glass plate may be 0.1 to 1.5 N / 25 mm as in the case where the thickness of the pressure-sensitive adhesive layer is 20 μm. Alternatively, a numerical range larger than 0.1 to 1.5 N / 25 mm or a smaller numerical range may be used depending on the thickness of the pressure-sensitive adhesive layer.

  The pressure-sensitive adhesive film of the present invention can be used to protect an adherend from a chemical polishing liquid (etching liquid) by bonding it to a glass substrate as an adherend, an ITO surface of a touch panel, or the opposite surface. In this case, it is preferable that the resin film substrate and the pressure-sensitive adhesive layer have sufficient transparency. The touch panel may be a touch panel in which a transparent conductive film such as an ITO film is formed on at least one surface of a base material made of a glass substrate or the like. As a surface protection film of this invention, it can stick to the surface on the said ITO film | membrane, or the surface on the opposite side so that peeling is possible through the said adhesive layer.

  Hereinafter, the present invention will be specifically described with reference to examples.

<Manufacture of acrylic copolymer>
[Example 1]
Nitrogen gas was introduced into a reactor equipped with a stirrer, a thermometer, a reflux condenser, and a nitrogen inlet tube, and the air in the reactor was replaced with nitrogen gas. Thereafter, 100 parts by weight of a solvent (ethyl acetate) was added to the reaction apparatus together with 95 parts by weight of 2-ethylhexyl acrylate and 5 parts by weight of 6-hydroxyhexyl acrylate. Thereafter, 0.1 part by weight of azobisisobutyronitrile as a polymerization initiator was added dropwise over 2 hours, reacted at 65 ° C. for 8 hours, and the acrylic copolymer solution of Example 1 having a weight average molecular weight of 500,000 was obtained. 1 was obtained.
[Examples 2-6 and Comparative Examples 1-3]
Acrylic copolymer solution 1 used in Example 1 above, except that the monomer composition is as described in (A), (B-1), and (B-2) of Table 1. In the same manner as above, acrylic copolymer solutions used in Examples 2 to 6 and Comparative Examples 1 to 3 were obtained.

<Production of pressure-sensitive adhesive composition and pressure-sensitive adhesive film>
[Example 1]
For the acrylic copolymer solution 1 produced as described above (of which 100 parts by weight of the acrylic copolymer), as a crosslinking agent, 3.0 parts by weight of coronate HL and as a silane coupling agent, KBE- 0.02 part by weight of 403 (3-glycidoxypropyltriethoxysilane) was added and mixed by stirring to obtain a pressure-sensitive adhesive composition of Example 1. The pressure-sensitive adhesive composition is applied onto a release film made of a silicone resin-coated polyethylene terephthalate (PET) film, and then dried at 90 ° C. to remove the solvent, and the pressure-sensitive adhesive layer has a thickness of 20 μm. A film was obtained.
Thereafter, the adhesive film is transferred to one surface of a resin film substrate made of a polyethylene terephthalate (PET) film having a thickness of 75 μm, and “resin film substrate / adhesive layer / release film (silicone resin-coated PET film)” The adhesive film of Example 1 which has the laminated structure of was obtained.
[Examples 2-6 and Comparative Examples 1-3]
The composition of the additive is as described in (C) and (D) of Table 1, and the thickness of the resin film substrate is as described in Table 2 except that the thickness of the resin film substrate is as described in Table 2. The adhesive films of Examples 2 to 6 and Comparative Examples 1 to 3 were obtained in the same manner as the adhesive film.

In Table 1, the compounding ratio of each component is indicated by enclosing numerical values in parts by weight in parentheses. In principle, the total of the parts by weight of the monomers (A), (B-1), and (B-2) (parts by weight of the copolymer) is 100 parts by weight, but this is not necessarily the case. . The total amount of monomers (parts by weight of copolymer) is 93 parts by weight in Example 6, 101 parts by weight in Comparative Example 1, 91 parts by weight in Comparative Example 2, and 105 parts by weight in Comparative Example 3.
In addition, Table 3 shows the names of the abbreviations of the components used in Table 1. Coronate (registered trademark) HX and L-45 are trade names of Nippon Polyurethane Industry Co., Ltd. D-110N is a trade name of Mitsui Chemicals, Inc. KBE-403, KBM-5103, KBE-903, KBM-802, X-41-1810, and X-41-1056 are trade names of Shin-Etsu Chemical Co., Ltd.

(Measurement method of adhesive strength)
The pressure-sensitive adhesive films in Examples 1 to 6 and Comparative Examples 1 to 3 were bonded to the non-tin surface washed with acetone of soda lime glass with a pressure roll. Then, after autoclaving at 50 ° C. and 0.5 MPa × 20 minutes, it was returned to an atmosphere of 23 ° C. and 50% RH, and the adhesive film after 1 hour was passed through a tensile tester at a speed of 300 mm / min in the 180 ° direction. The peel strength when peeled at is the adhesive strength of the adhesive film.

(Contamination test method)
After measuring the adhesive strength, the surface of the adherend (soda lime glass plate) is visually confirmed to determine the contamination caused by the adhesive layer. Contamination was evaluated according to the following criteria according to the contamination state of the adherend.
-Evaluation of contamination (O): The adhesive layer does not contaminate the adherend at all.
-Evaluation of contamination (△): The adhesive layer partially contaminates the adherend.
-Evaluation of contamination (x): The adhesive layer contaminates the adherend, and the adhesive layer is also transferred.

(Test method for penetration resistance to hydrofluoric acid)
After sticking the adhesive film in Examples 1-6 and Comparative Examples 1-3 on the surface of the soda-lime glass plate in which the level | step difference of 4 micrometers was provided with the crimping | compression-bonding roll, the temperature of 27 degreeC density | concentration of 15% After immersing in a hydrofluoric acid aqueous solution for 150 seconds, it was thoroughly washed with water. Then, after peeling an adhesive film, the adherend surface of the glass substrate with which the adhesive film was bonded together is confirmed visually, and the presence or absence of corrosion of the soda-lime glass plate by permeation of hydrofluoric acid is confirmed. The hydrofluoric acid permeation resistance was evaluated according to the following criteria according to the presence or absence and degree of corrosion of the glass substrate. ・ Evaluation of hydrofluoric acid permeation resistance (○): When there is no corrosion of the glass substrate .
-Evaluation of hydrofluoric acid permeation resistance (△): When hydrofluoric acid permeates the place where the adhesive film was pasted and a part of the glass substrate is corroded.
-Evaluation of hydrofluoric acid permeation resistance (x): When the hydrofluoric acid permeates the place where the adhesive film was pasted and the glass substrate is corroded.

(Test method for erosion from the edge of the glass plate)
An ITO film was vapor-deposited on both surfaces of a glass plate for a touch panel sensor having a thickness of 0.4 mm and a rectangular shape with a length and width of 10 cm each. As shown in FIG. 1, four pressure-sensitive adhesive films of Example 1 cut to a size of 10 cm × 10 cm were prepared, and the pressure-sensitive adhesive film 4 protruded with a width of 0.3 mm from the tip of one side of the glass plate 1. The two laminates of Example 1 were prepared by pasting on the ITO film 5 on both surfaces of the glass plate 1 through the adhesive layer 3 of the adhesive film 4. These laminates were immersed in a hydrofluoric acid aqueous solution having a temperature of 27 ° C. and a concentration of 15%, one laminate for 5 minutes, and the other laminate for 10 minutes, and then washed with water at room temperature for 5 minutes. Then, peel the adhesive film on both sides from each laminate, measure the maximum distance from one end of the glass plate in the range where the surface of the ITO film was discolored by the permeation of hydrofluoric acid, and the erosion distance It was. Moreover, it replaced with the adhesive film of Example 1, and produced the laminated body of the comparative example 1 similarly except having used the adhesive film of the comparative example 1, and measured the erosion distance. The test results are shown in Table 4.

In addition, the relationship between the erosion time and the erosion distance is shown in FIG.
According to FIG. 2, when the adhesive film of Example 1 was used, the adhesive film on the adherend surface of the glass plate as the adherend was immersed in a hydrofluoric acid aqueous solution having a temperature of 27 ° C. and a concentration of 15%. It can be confirmed that there is no permeation of hydrofluoric acid for at least 150 seconds or more in the portion where the distance from the end of the bonding surface of the film is 80 μm or more.

(Testing method for corrosiveness to ITO)
The pressure-sensitive adhesive layer of the pressure-sensitive adhesive film is bonded to the surface of the ITO film, and the surface resistivity (SR1) of the ITO film after the passage of 85 ° C. and 90% RH × 1000 hours is measured. The surface resistivity (Ω / □) was measured using a resistivity meter Hiresta UP-HT450 (manufactured by Mitsubishi Chemical Analytech). The surface resistivity of the ITO film before bonding the adhesive layer of the adhesive film is the initial value (SR0), and the change rate (%) of the surface resistivity is calculated by “100 × (SR1-SR0) / SR0”. To do. Corrosivity to ITO was evaluated according to the following criteria according to the rate of change in surface resistivity.
-Corrosive evaluation (O): When the rate of change in surface resistivity is less than 2%.
Corrosion evaluation (△): When the rate of change of surface resistivity is 2% or more and less than 5%.
-Corrosive evaluation (x): When the rate of change in surface resistivity is 5% or more.

According to the test results shown in Table 2, the adhesive films of Examples 1 to 6 have moderate adhesive strength, and are good in each of contamination, hydrofluoric acid resistance, and corrosivity to ITO. (○).
The pressure-sensitive adhesive film of Comparative Example 1 was slightly inferior in contamination due to its high adhesive strength. Further, since the pressure-sensitive adhesive layer did not contain a silane coupling agent, water repellency was not added, and the hydrofluoric acid permeation resistance was poor.
Since the adhesive film of Comparative Example 2 had high adhesive strength, the contamination was poor. Moreover, since the adhesive contains carboxylic acid, the corrosivity to ITO was inferior.
Since the adhesive film of Comparative Example 3 had high adhesive strength, the contamination was poor. Further, since the pressure-sensitive adhesive layer did not contain a silane coupling agent, water repellency was not added, and the hydrofluoric acid permeation resistance was poor.

  The present invention provides an adhesive film and a surface protective film that not only prevent permeation of hydrofluoric acid, which is the main component of the chemical polishing liquid, but also generate no adhesive residue between the glass substrate as the adherend and the adhesive layer. Therefore, industrial utility value is great.

DESCRIPTION OF SYMBOLS 1 ... Glass plate, 2 ... Resin film base material, 3 ... Adhesive layer, 4 ... Adhesive film, 5 ... ITO film | membrane.

Claims (3)

A surface protective film for chemical polishing treatment having an adhesive layer on one side of a resin film substrate, wherein the resin film substrate has a thickness of 75 μm or more, and the adhesive layer is (A) an alkyl group carbon. A C1-C14 alkyl (meth) acrylate monomer, and (B) at least one copolymerizable vinyl monomer selected from the group of a hydroxyl group-containing vinyl monomer and a nitrogen-containing vinyl monomer, and a carboxyl group-containing monomer. Formed using a pressure-sensitive adhesive composition comprising an acrylic copolymer copolymerized without containing , (C) a silane coupling agent, and (D) a crosslinking agent,
The silane coupling agent has at least one organic functional group selected from the group consisting of an epoxy group, a (meth) acryloxy group, a mercapto group, and an amino group,
The pressure-sensitive adhesive layer is laminated with a thickness of 10 to 35 μm, and when the pressure-sensitive adhesive layer has a thickness of 20 μm, the adhesive force to the glass plate is 0.1 to 1.5 N / 25 mm. A surface protective film for chemical polishing treatment . The pressure-sensitive adhesive layer comprises (A) 80 to 95 parts by weight of at least one alkyl (meth) acrylate monomer having an alkyl group with C1 to C14, and (B) a hydroxyl group-containing vinyl monomer and a nitrogen-containing vinyl monomer. 100 parts by weight of an acrylic copolymer containing 5 to 20 parts by weight of at least one copolymerizable vinyl monomer selected from the group of (C), and 0.01 to 1 part by weight of (C) a silane coupling agent And (D) a surface protection for chemical polishing treatment according to claim 1, characterized in that it is formed using a pressure-sensitive adhesive composition containing 0.01 to 10 parts by weight of a crosslinking agent. the film. The surface protection film for chemical polishing according to claim 1 or 2 , wherein the crosslinking agent is an isocyanate compound.

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