KR20180111470A - Antistatic silicon adhesive composition and protective sheet - Google Patents

Abstract

Provided is an antistatic silicone adhesive composition. More specifically, provided is an antistatic silicone adhesive composition ensuring high transparency and excellent substrate adhesion. Moreover, provided is a protective sheet which is excellent in adhesion with base films and adhesive layers and ensures high transparency. To this end, the antistatic silicone adhesive composition contains a silicone adhesive and an antistatic agent. The antistatic agent is an ionic compound composed of an anion and a cation, and the both do not contain carbon atom.

Description

TECHNICAL FIELD [0001] The present invention relates to an antistatic silicone pressure-

The present invention relates to a protective sheet used for protecting a device, and an antistatic silicone pressure-sensitive adhesive composition usable in a pressure-sensitive adhesive layer in the protective sheet.

Conventionally, in a device such as an optical member or an electronic member, in order to prevent surface scratches during processing such as processing, assembly, and inspection, when a protective sheet composed of a base film and a pressure-sensitive adhesive layer is adhered to the surface of the device . This protective sheet is peeled off from the device at the time when the need for protection is eliminated, but there is a case where static electricity is generated by the peeling charge.

When static electricity is generated, dust or dirt in the air adheres to the device, leading to defective devices. Therefore, it is required that the pressure-sensitive adhesive layer of the protective sheet is provided with antistatic property so that static electricity is not generated. A technique for imparting antistatic properties to a pressure-sensitive adhesive layer made of an acrylic pressure-sensitive adhesive has been established, and a general antistatic agent may be added to an acrylic pressure-sensitive adhesive.

[0003] In recent years, as an optical member, a transition from a liquid crystal device to an organic light emitting diode (OLED) device has been actively performed. Further, studies on an OLED device having a flexible property (hereinafter referred to as a " flexible OLED device ") have been actively studied. Since the flexible OLED device is flexible, unlike a liquid crystal device or an ordinary OLED device, there arises a problem that it is difficult to peel it from a flexible OLED device when a conventional protective sheet is used. Further, in the inspection process of the OLED device, the protection sheet is required to have heat resistance because it may be exposed under high temperature conditions. Under such a background, a silicone-based pressure-sensitive adhesive is preferable as a pressure-sensitive adhesive for forming the pressure-sensitive adhesive layer.

A technique of adding an antistatic agent to a silicone-based pressure sensitive adhesive is disclosed in Patent Document 1. In the example of Patent Document 1, lithium bistrifluoromethanesulfonylimide is used as an antistatic agent.

Japan Specification No. 2009-530470

Here, in the light emission inspection of the OLED device, since the inspection is performed at a stricter level than the light emission inspection of the liquid crystal device, the protective sheet is required to have high transparency. However, in the silicone-based pressure-sensitive adhesive composition to which the antistatic agent described in Patent Document 1 is added, high transparency required for the emission test of the OLED device is not obtained. Further, the pressure-sensitive adhesive layer made of the silicone-based pressure-sensitive adhesive composition described in Patent Document 1 has a problem that adhesiveness to the base film is low.

An object of the present invention is to provide an antistatic silicone pressure-sensitive adhesive composition which is excellent in transparency and adhesion to a substrate and which has high transparency and excellent adhesion between a base film and a pressure-sensitive adhesive layer. .

In order to achieve the above object, first, the present invention provides an antistatic silicone pressure-sensitive adhesive composition comprising a silicon pressure-sensitive adhesive and an antistatic agent, wherein the antistatic agent is an ionic compound comprising an anion and a cation, (1), wherein all of the carbon atoms are free of carbon atoms (Invention 1).

The antistatic silicone pressure-sensitive adhesive composition according to the invention (Invention 1) has high transparency and excellent substrate adhesion by containing the antistatic agent.

In the invention (Invention 1), it is preferable that the anion contains a fluorine atom (invention 2).

In the above invention (Invention 1 or 2), it is preferable that the cation is a metal cation (invention 3).

In the invention (Invention 3), it is preferable that the metal cation is an alkali metal (invention 4).

In the above inventions (inventions 1 to 4), it is preferable that a dispersant for dispersing the antistatic agent is contained (invention 5).

In the invention (Invention 5), it is preferable that the dispersant is an alkylene glycol dialkyl ether (invention 6).

Secondly, the present invention provides a protective sheet for protecting a device, which comprises a base film and a pressure-sensitive adhesive layer laminated on one side of the base film, wherein the pressure-sensitive adhesive layer comprises the antistatic silicone pressure- 1 to 6) (Claim 7).

In the invention (invention 7), it is preferable that the device is a flexible device (invention 8).

The antistatic silicone pressure-sensitive adhesive composition according to the present invention has high transparency and excellent substrate adhesion. In addition, the protective sheet according to the present invention has high transparency and excellent adhesion between the base film and the pressure-sensitive adhesive layer.

1 is a cross-sectional view of a protective film according to an embodiment of the present invention;

Hereinafter, an embodiment of the present invention will be described.

[Antistatic silicone pressure-sensitive adhesive composition]

The antistatic silicone pressure-sensitive adhesive composition according to one embodiment of the present invention (hereinafter sometimes simply referred to as "pressure-sensitive adhesive composition") contains a silicone pressure-sensitive adhesive and an antistatic agent, and preferably further contains a dispersing agent . The pressure-sensitive adhesive composition according to the present embodiment is suitably used for forming a pressure-sensitive adhesive layer of a protective sheet for protecting the surface of a device or the like.

(1) silicone adhesive

As the silicone pressure-sensitive adhesive, it is preferable to stick to the adherend (device) to be protected and peel off from the adherend, and to exhibit stable adherence even under high temperature (for example, 90 to 150 DEG C) It is preferable to select it. For example, when the adherend is a flexible device such as a flexible OLED device, it is preferable to select a silicone adhesive which is excellent in re-peeling property so that the protective sheet can easily peel off from the flexible device. Further, the silicone pressure-sensitive adhesive exhibits a stable adhesive force even at a high temperature as compared with the acrylic pressure-sensitive adhesive, and is excellent in heat resistance.

As the silicone adhesive, a condensation type silicone adhesive or an addition reaction type silicone adhesive may be used. However, from the viewpoint of re-releasability, an addition reaction type silicone adhesive is preferable.

The addition reaction-type silicone pressure-sensitive adhesive is characterized by containing an addition reaction type silicone resin obtained from a first polydimethylsiloxane having at least two alkenyl groups in one molecule and a second polydimethylsiloxane having at least two hydrosilyl groups in one molecule , And it is particularly preferable to further contain silicone resin.

As the alkenyl group contained in the first polydimethylsiloxane, a monovalent hydrocarbon group such as a vinyl group, an allyl group, a propenyl group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group and an octenyl group can be enumerated. Particularly preferred.

The content of the alkenyl group in the first polydimethylsiloxane (the ratio of the number of alkenyl groups to the number of methyl groups bonded to silicon atoms) is preferably 0.005 to 0.1 mol%, more preferably 0.01 to 0.05 mol% desirable. The alkenyl group preferably has both ends of the molecular chain and may have a side chain. When at least two alkenyl groups are contained in one molecule of the first polydimethylsiloxane and the content of the alkenyl group is in the above range, a crosslinked structure having a high crosslinking density is formed, and a pressure-sensitive adhesive layer having excellent re-releasability can be obtained.

The degree of polymerization (number of siloxane bonds) of the first polydimethylsiloxane is preferably 200 to 5,000, particularly preferably 500 to 3,000. The content of the hydrosilyl group in the second polydimethylsiloxane is preferably 2 to 300 in one molecule, particularly preferably 4 to 200. The polymerization degree of the second polydimethylsiloxane is preferably from 50 to 2,000, particularly preferably from 100 to 1,500. The blending ratio of the second polydimethylsiloxane to 100 parts by mass of the first polydimethylsiloxane is preferably 0.01 to 20 parts by mass, particularly preferably 0.1 to 10 parts by mass. The addition reaction of the first polydimethylsiloxane with the second polydimethylsiloxane is satisfactorily performed because the content of each functional group and the blending ratio of the second polydimethylsiloxane to the first polydimethylsiloxane fall within the above range.

The first polydimethylsiloxane preferably has no hydrosilyl group, and the second polydimethylsiloxane preferably has no alkenyl group.

The weight average molecular weight of the first polydimethylsiloxane is preferably from 20,000 to 130,000, and particularly preferably from 300,000 to 1,000,000. The weight average molecular weight of the second polydimethylsiloxane is preferably 300 to 1,400, and particularly preferably 500 to 1,200. In the present specification, the weight average molecular weight is a value in terms of standard polystyrene measured by a gel permeation chromatography (GPC) method.

As the silicone resin can be used, for example, a MQ resin consisting of one functional siloxane unit _{[(CH₃) 3 SiO 1/} 2] of M units, and a four-functional siloxane units Q units of [SiO _4/2]. The molar ratio of M units / Q units is preferably 0.6 to 1.7. This silicone resin has a role of imparting tackiness to the silicone pressure-sensitive adhesive.

The amount of the silicone resin to be blended with 100 parts by mass of the addition reaction type silicone resin is preferably 1 part by mass or more, particularly preferably 3 parts by mass or more, more preferably 5 parts by mass or more. The lower limit of the compounding amount of the silicone resin is the above, whereby a desired adhesive force can be obtained, and the resulting protective sheet can be prevented from unintentionally peeling off from the adherend (device). The upper limit of the blending amount is preferably 40 parts by mass or less, particularly preferably 30 parts by mass or less, more preferably 20 parts by mass or less. The upper limit of the amount of the silicone resin to be blended can prevent the adhesion force from becoming too high, and the re-peeling property of the resultant protective sheet can be secured.

The addition reaction type silicone pressure sensitive adhesive preferably contains a catalyst. The catalyst is not particularly limited as long as it can cure the addition reaction type silicone resin (addition reaction of the first polydimethylsiloxane and the second polydimethylsiloxane), but among these, a platinum group metal compound is preferable. Examples of the platinum group metal compound include fine platinum particles, fine particulate platinum adsorbed on a carbon powder carrier, chloroplatinic acid, alcohol-modified chloroplatinic acid, olefin complexes of chloroplatinic acid, palladium and rhodium . By containing such a catalyst, the curing reaction of the addition reaction type silicone resin can be promoted more efficiently.

The blending amount of the catalyst relative to 100 parts by mass of the addition reaction type silicone resin is preferably 0.01 to 3 parts by mass, particularly preferably 0.05 to 2 parts by mass.

(2) Antistatic agent

The antistatic agent in the present embodiment is an ionic compound composed of an anion and a cation, and both the anion and the cation do not contain a carbon atom. Such an antistatic agent is excellent in compatibility with a silicone pressure-sensitive adhesive, so that the resulting pressure-sensitive adhesive composition has high transparency. Therefore, the protective sheet provided with the pressure-sensitive adhesive layer made of the pressure-sensitive adhesive composition of the present invention also has high transparency. For example, the light-emitting test of the OLED device to which the protective sheet is adhered can be performed without any problem.

Further, the pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition in which the antistatic agent is blended exhibits high adhesiveness to the base film of the protective sheet, that is, the substrate adhesion is excellent. Therefore, the protective sheet has high stability and reliability as a product, and there is no possibility that the pressure-sensitive adhesive layer or the pressure-sensitive adhesive composition remains on the adherend when the protective sheet is peeled from the adherend.

The anion constituting the ionic compound preferably contains a fluorine atom from the viewpoint of compatibility with the silicone pressure-sensitive adhesive and substrate adhesion. Specific examples thereof include bisfluorosulfonylimide (N (SO ₂ F) ₂ ^- ), hexafluorophosphoric acid (PF ₆ ^- ) and boron tetrafluoride (BF ₄ ^- ), Among them, bisfluorosulfonylimide which is excellent in compatibility with a silicone pressure-sensitive adhesive and in adhesion to a substrate is preferable.

The cation constituting the ionic compound is preferably a metal cation from the viewpoints of compatibility with the silicon pressure-sensitive adhesive and substrate adhesion. As the metal cations, e.g., lithium (Li ^+), sodium (Na ^+), potassium (K ^+), rubidium (Rb ^+), cesium (Cs ⁺⁾ alkali metals, beryllium (Be ^{2 +),} such as, magnesium there may be mentioned (Mg ^{2 +),} calcium (Ca ^{+ 2),} strontium (Sr ^{+ 2),} an alkaline earth metal such as barium (Ba ^{+ 2)} and so on. Among the above, from the viewpoints of compatibility with the silicone pressure-sensitive adhesive and substrate adhesion, an alkali metal is preferable, and potassium is particularly preferable.

Therefore, in this embodiment, the most preferable antistatic agent is potassium N, N-bis (fluorosulfonyl) imide. The antistatic silicone pressure-sensitive adhesive composition using potassium N, N-bis (fluorosulfonyl) imide has very high transparency and the pressure-sensitive adhesive layer comprising the pressure-sensitive adhesive composition has a very high adhesion with the base film. Therefore, a protective sheet having a pressure-sensitive adhesive layer composed of an antistatic silicone pressure-sensitive adhesive composition using potassium N, N-bis (fluorosulfonyl) imide as an antistatic agent is excellent as a protective sheet for OLED devices.

The antistatic agent may be used singly or in combination of two or more kinds.

The content of the antistatic agent in the antistatic silicone pressure-sensitive adhesive composition according to the present embodiment is preferably 0.1 part by mass or more as a lower limit value with respect to 100 parts by mass of the subject of the silicone pressure-sensitive adhesive (silicone resin, especially addition reaction type silicone resin) Particularly preferably 0.5 part by mass or more, more preferably 1 part by mass or more. If the lower limit of the content is the above range, good antistatic properties can be obtained. On the other hand, the content of the antistatic agent is preferably 5 mass parts or less, more preferably 4 mass parts or less, and most preferably 3 mass parts or less. If the upper limit of the content is above, the adhesion of the base material of the pressure-sensitive adhesive layer becomes higher.

(3) Dispersing agent

The antistatic agent is preferably used alone, but it is also preferable to use a dispersant in combination. When the solubility of the antistatic agent is insufficient, the solubility can be improved by using a dispersing agent in combination to increase the ionic conductivity of the antistatic agent, thereby further improving the antistatic property.

As the dispersing agent, for example, alkylene glycol dialkyl ether and the like are preferably used. Specific examples of the alkylene glycol dialkyl ether include octaethylene glycol dibutyl ether, octaethylene glycol diethyl ether, octaethylene glycol dimethyl ether, hexaethylene glycol dibutyl ether, hexaethylene glycol diethyl ether, hexaethylene glycol dimethyl ether, Tetraethylene glycol dibutyl ether, tetraethylene glycol diethyl ether, tetraethylene glycol dimethyl ether (hereinafter may be referred to as "tetraglyme"), triethylene glycol diethyl ether, and triethylene glycol dimethyl ether. . Of these, tetraglyme, which is particularly excellent in the dispersibility of potassium N, N-bis (fluorosulfonyl) imide, is preferred. These dispersants may be used singly or in combination of two or more kinds.

The blending amount of the dispersant is preferably 0.1 part by mass or more, particularly preferably 0.5 part by mass or more, and more preferably 0.9 part by mass or more, as a lower limit value with respect to 1 part by mass of the antistatic agent. If the lower limit of the amount of the dispersing agent is above, the antistatic effect is further improved. The upper limit of the blending amount is preferably 2.0 parts by mass or less, particularly preferably 1.5 parts by mass or less, and more preferably 1.1 parts by mass or less. If the upper limit of the blending amount of the dispersing agent is the above, the transparency of the resulting pressure-sensitive adhesive composition can be kept high.

(4) Other components

The antistatic silicone pressure-sensitive adhesive composition in the present embodiment may contain various additives such as a crosslinking agent, a reaction inhibitor, and a silane coupling agent in addition to the above components.

[Protective Sheet]

A protective sheet according to an embodiment of the present invention is used for protecting a device in order to prevent scratches on the surface of the device during processing such as processing, assembling, and inspection of the device.

1, the protective sheet 1 according to the present embodiment includes a base film 11, a pressure-sensitive adhesive layer 12 laminated on one surface (lower side in Fig. 1) of the base film 11, And a release sheet 13 laminated on a surface of the pressure-sensitive adhesive layer 12 opposite to the base film 11 (lower side in Fig. 1). The release sheet 13 is for protecting the pressure-sensitive adhesive layer 12 until the protective sheet 1 is used and is peeled off when the protective sheet 1 is used. In the protective sheet 1 according to the present embodiment, the release sheet 13 may be omitted.

1. Each member

(1)

It is preferable that the base film 11 has heat resistance to a high temperature (for example, 90 to 150 占 폚) applied in inspection of a device to be protected. Further, when the base film 11 is used in a device in which a light emission test is performed, particularly, in an OLED device, it is preferable that the base film 11 has high transparency.

As the base film 11, for example, a resin such as polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyimide, polyether imide, polycarbonate, polymethylpentene, polyphenylene sulfide, , And may be a single layer film or a laminate of a plurality of layers of the same or different types. Of the above, polyethylene terephthalate films are particularly preferable from the viewpoints of heat resistance, transparency and cost.

The plastic film may contain an additive such as a heat resistance improving agent and an ultraviolet absorber. When high transparency is required, it is preferable that the plastic film does not contain a filler.

In the base film 11, a surface treatment by an oxidation method, a surface irregularity method or the like, or a primer treatment may be carried out, if desired, for the purpose of improving adhesion with the pressure-sensitive adhesive layer 12. Examples of the oxidation method include corona discharge treatment, plasma discharge treatment, chromium oxidation treatment (wet type), flame treatment, hot air treatment, ozone, ultraviolet ray irradiation treatment and the like. Method, spray treatment method, and the like. These surface treatment methods are appropriately selected depending on the kind of the base film.

The thickness of the base film 11 is preferably 25 占 퐉 or more, more preferably 38 占 퐉 or more, and more preferably 50 占 퐉 or more, in consideration of heat resistance and workability of adhering and peeling. In the case where the device to be protected is a flexible device, it is particularly preferable that the protective device is 50 mu m or more from the viewpoint of operability of attaching and peeling. On the other hand, in consideration of workability and cost of attaching and peeling, the thickness is preferably 150 占 퐉 or less, more preferably 125 占 퐉 or less, and further preferably 100 占 퐉 or less.

(2) Pressure-sensitive adhesive layer

The pressure-sensitive adhesive layer 12 is formed of the antistatic silicone pressure-sensitive adhesive composition described above.

The thickness of the pressure-sensitive adhesive layer 12 is preferably 15 占 퐉 or more, particularly preferably 20 占 퐉 or more, and more preferably 25 占 퐉 or more, from the viewpoint of adhesiveness. The thickness of the pressure-sensitive adhesive layer 12 is preferably 75 占 퐉 or less, more preferably 50 占 퐉 or less, and most preferably 30 占 퐉 or less, from the viewpoint of releasability.

(3) Peeling sheet

The release sheet 13 is not particularly limited as long as it does not adversely affect the pressure-sensitive adhesive layer 12. Examples of the release sheet 13 include a polyethylene film, a polypropylene film, a polybutene film, a polybutadiene film, a polymethylpentene film, (Meth) acrylic acid copolymer film, a polyvinyl chloride film, a vinyl chloride film, a vinyl chloride copolymer film, a polyethylene terephthalate film, a polyethylene naphthalate film, a polybutylene terephthalate film, a polyurethane film, an ethylene vinyl acetate film, an ionomer resin film, , An ethylene · (meth) acrylate copolymer film, a polystyrene film, a polycarbonate film, a polyimide film, and a fluororesin film. These crosslinked films are also used. Further, these laminated films may be used. Of these, polyethylene terephthalate films having excellent handling properties are preferable.

It is preferable that the surface of the release sheet 13 contacting the pressure-sensitive adhesive layer 12 is not subjected to the release treatment, that is, the release agent layer is not present. When the pressure-sensitive adhesive layer 12 is composed of a silicone pressure-sensitive adhesive composition, a fluorine releasing agent is generally used for the releasing agent layer, but when a releasing agent layer made of a fluorine releasing agent is provided, the fluorine component migrates to the pressure- 12 may be unstable in terms of antistatic property or adhesive strength.

In order to more effectively prevent the static electricity generated when the release sheet 13 is peeled off from the pressure-sensitive adhesive layer 12, one or both of the surface of the release sheet 13, which is in contact with the pressure- Prevention layer may be provided.

The thickness of the release sheet 14 is not particularly limited, but is preferably 15 to 100 占 퐉, and particularly preferably 25 to 75 占 퐉.

2. Manufacturing method of protective sheet

In order to manufacture the protective sheet 1 according to the present embodiment, for example, a coating liquid containing an antistatic silicone pressure-sensitive adhesive composition and, if desired, a diluent is applied to one surface of a base film, The pressure-sensitive adhesive layer 12 is formed by curing.

The diluent is not particularly limited, and various diluents can be used. For example, hydrocarbon compounds such as toluene, hexane and heptane, acetone, ethyl acetate, methyl ethyl ketone, methyl isobutyl ketone, and mixtures thereof.

The application of the coating liquid of the antistatic silicone pressure-sensitive adhesive composition may be carried out by a conventional method. For example, the coating liquid may be applied by a bar coating method, a knife coating method, a roll coating method, a blade coating method, a die coating method or a gravure coating method . When the coating liquid is applied, it is preferable to heat and dry the coating film.

When the subject of the antistatic silicone pressure-sensitive adhesive composition is an addition reaction-type silicone pressure-sensitive adhesive, it is preferable that the coating film is thermally cured. In this case, the heating temperature is preferably 80 to 180 DEG C, and the heating time is preferably 10 to 120 seconds.

When the pressure-sensitive adhesive layer 12 is formed as described above, the release sheet 13 is bonded to the pressure-sensitive adhesive layer 12 to obtain the protective sheet 1.

In the above manufacturing method, the pressure-sensitive adhesive layer 12 is formed on the base film 11, but the pressure-sensitive adhesive layer 12 is formed on the release sheet 13, May be combined.

3. Properties

(1) Surface resistivity

The surface resistivity of the pressure-sensitive adhesive layer 12 in the protective sheet 1 can be measured in accordance with JIS K6911. The upper limit of the surface resistivity of the pressure-sensitive adhesive layer 12 is preferably 1 x 10 ¹³ Ω / sq or less, more preferably 5 x 10 ¹² Ω / sq or less, and even more preferably 1 x 10 ¹² Ω / sq or less . The upper limit of the surface resistivity is as described above, whereby the antistatic property of the protective sheet 1 is excellent. The surface resistivity is preferably at least 1 x 10 ⁹ ? / Sq, more preferably at least 5 x 10 ⁹ ? / Sq, and most preferably at least 1 x 10 ¹⁰ ? / Sq. By the above-mentioned lower limit value of the surface resistivity, it is possible to exhibit good antistatic property without impairing the adhesive property.

(2) Haze value

The haze value of the laminate (the laminate of the base film 11 and the pressure-sensitive adhesive layer 12 in the present embodiment) other than the release sheet 13 in the protective sheet 1 according to the present embodiment is preferably 2% Or less, more preferably 1.9% or less, and most preferably 1.8% or less. The above haze value makes the degree of transparency of the protective sheet 1 adhered to the adherend high. As a result, for example, the emission test of the OLED device to which the protective sheet 1 is adhered can be performed without any problem. The lower limit value of the haze value is not particularly limited, and is particularly preferably 0%. Here, the haze value in this specification is a value measured in accordance with JIS K7136: 2000.

The protective sheet 1 according to the present embodiment can achieve a low haze value as described above by using the above-described antistatic agent in the pressure-sensitive adhesive layer 12.

(3) Adhesion

The protective sheet 1 according to the present embodiment preferably has an adhesive force of 0.01 N / 25 mm or more as the lower limit value, particularly preferably 0.015 N / 25 mm or more, and more preferably 0.02 N / Is more preferable. The above lower limit of the adhesive force can prevent the protective sheet 1 from inadvertently peeling off from the adherend (device).

The adhesive force is preferably 0.2 N / 25 mm or less as an upper limit value, particularly preferably 0.15 N / 25 mm or less, and more preferably 0.1 N / 25 mm or less. When the protective sheet 1 is peeled off from the adherend (device, in particular, flexible device) due to the upper limit of the adhesive force, the protective sheet 1 can be smoothly peeled off without damaging the device .

Basically, the adhesive force in this specification refers to the adhesive force measured by the 180 ° peeling technique in accordance with JIS Z0237: 2009, but the measurement sample has a width of 25 mm and a length of 100 mm, The adherend is pressed at 0.5 MPa and at 50 캜 for 20 minutes and then allowed to stand at normal pressure, 23 캜 and 50% RH for 24 hours, and then measured at a peeling rate of 300 mm / min.

4. Usage

The protective sheet 1 according to the present embodiment is used for protecting devices in order to prevent scratches on the surface of the device during processing such as processing, assembly, and inspection of the device. However, the present invention is not limited to these applications.

The device to be protected by the protective sheet 1 may be, for example, an optical member or an electronic member. In the present embodiment, it is preferable that the device is a flexible device, It is preferable that the device is a device requiring a light emission test or a high temperature condition. Of these, OLED devices are more preferred, and flexible OLED devices are particularly desirable.

The protective sheet 1 according to the present embodiment has high transparency because the pressure-sensitive adhesive layer 12 has high transparency. Therefore, the light emission inspection of the OLED device to which the protective sheet 1 is adhered can be performed without any problem. Further, since the pressure-sensitive adhesive layer 12 formed of the silicone pressure-sensitive adhesive composition is excellent in re-peeling property, it can be easily peeled from a flexible device. Further, since the pressure-sensitive adhesive layer 12 formed of the silicone pressure-sensitive adhesive composition is excellent in heat resistance, the OLED device exhibits stable adhesion even at the time of inspection at high temperature or after the inspection. The protective sheet 1 is also excellent in adhesion between the base film 11 and the pressure-sensitive adhesive layer 12, so that the stability and reliability of the product are high. Further, when the protective sheet 1 is peeled off from the adherend, , There is no possibility that the pressure-sensitive adhesive layer 12 or the pressure-sensitive adhesive composition remains on the side of the adherend. In the protective sheet 1 according to the present embodiment, since the pressure-sensitive adhesive layer 12 has antistatic properties, it is difficult for the static electricity to be generated when the protective sheet 1 is peeled from the device, Dust or dirt can be prevented from adhering to the device.

The above-described embodiments are described for the purpose of facilitating understanding of the present invention, and are not described for limiting the present invention. Therefore, each element disclosed in the above embodiment is intended to include all design modifications and equivalents falling within the technical scope of the present invention.

For example, another layer (for example, antistatic layer) may be interposed between the base film 11 and the pressure-sensitive adhesive layer 12 in the protective sheet 1, and in the base film 11 Another layer (for example, an antistatic layer) may be laminated on the surface opposite to the pressure-sensitive adhesive layer 12 side.

(Example)

Hereinafter, the present invention will be described in more detail with reference to Examples and the like, but the scope of the present invention is not limited to these Examples and the like.

[Example 1]

1. Preparation of coating liquid of pressure-sensitive adhesive composition

100 parts by mass of an addition reaction type silicone resin (Shin-Etsu Chemical Co., Ltd., product name " KS-847H ") as a subject of a silicone adhesive, 5.0 parts by mass of silicone resin (Dow Corning Toray, and 0.5 parts by mass, ^-, a platinum catalyst (Toray · Dow Corning syaje, product name "SRX 212 cATALYST") 1.5 parts by weight of potassium as an antistatic agent, N, N- bis (fluoro sulfonyl) imide (FSI ⁺ K) And 0.5 parts by mass of tetraethylene glycol dimethyl ether as a dispersing agent were mixed and diluted with methyl ethyl ketone to prepare a coating liquid for the pressure-sensitive adhesive composition.

2. Manufacture of protective sheet

The coating liquid of the pressure-sensitive adhesive composition obtained in the above step was applied to one side of a PET film (Toyobo Co., Ltd., product name "Cosmo Shine A4300", thickness 75 μm) as a base film with a knife coater and then heat treated at 130 ° C. for 1 minute To form a pressure-sensitive adhesive layer having a thickness of 25 mu m. Next, a polyethylene terephthalate (PET) film (trade name: "Lumirra T60", no release agent layer, thickness 38 μm) as a release sheet was laminated on the pressure-sensitive adhesive layer to obtain a protective sheet.

[Examples 2 to 5]

A protective sheet was prepared in the same manner as in Example 1 except that the blending amount of the antistatic agent and the dispersant was changed as shown in Table 1 in the preparation of the coating liquid of the pressure-sensitive adhesive composition.

[Example 6]

100 parts by mass of an addition reaction-type silicone resin (Arakawa Chemical Industries, Ltd., product name: "Sirikosu KF-150") as a subject of the silicone pressure-sensitive adhesive, and 10.0 parts by mass of silicone resin (Arakawa Chemical Industries, and a platinum catalyst (Toray · Dow Corning syaje, product name "SRX 212 cATALYST") 1.5 parts by weight of potassium as an antistatic agent, N, N- bis (fluoro sulfonyl) imide (FSI K ^{+ -),} 0.5 parts by weight And 0.5 parts by mass of tetraethylene glycol dimethyl ether as a dispersant were mixed and diluted with methyl ethyl ketone, and this was used as a coating liquid for the pressure-sensitive adhesive composition.

[Comparative Example 1]

Except that 2.5 parts by mass of N-decalpyridinium bis (fluorosulfonyl) imide (Pry ⁺ FSI ^- ) as an antistatic agent was blended in the preparation of the coating liquid of the pressure-sensitive adhesive composition and the dispersing agent was not blended. A protective sheet was prepared in the same manner as in Example 1. [

[Comparative Example 2]

Except that 2.5 parts by mass of N-octyl-4-methylpyridinium hexafluorophosphate (Pry ⁺ PF ₆ ^- ) as an antistatic agent was blended in the preparation of the coating liquid of the pressure-sensitive adhesive composition and the dispersing agent was not blended A protective sheet was prepared in the same manner as in Example 1.

[Comparative Example 3]

Except that 2.5 parts by mass of lithium bis (trifluoromethanesulfon) imide (Li ⁺ TFSI ^- ) as an antistatic agent was blended in the preparation of the coating liquid of the pressure-sensitive adhesive composition and the dispersing agent was not blended. Similarly, a protective sheet was produced.

[Comparative Example 4]

A protective sheet was produced in the same manner as in Example 1 except that no antistatic agent and no dispersing agent were added in the preparation of the coating liquid for the pressure-sensitive adhesive composition.

Table 1 shows blending ratios of the materials used in Examples and Comparative Examples.

[Test Example 1] (Measurement of surface resistivity)

The protective sheet prepared in Examples and Comparative Examples was cut into a size of 50 mm x 50 mm, and the obtained sample was allowed to stand under the environment of 23 ° C and 50% RH for 24 hours. Thereafter, the release sheet was peeled off, and the surface resistivity (Ω (μm)) according to JIS K6911 was measured with respect to the exposed surface of the pressure-sensitive adhesive layer using a resistivity meter (Mitsubishi Chemical Industries, / sq) was measured. The results are shown in Table 2. The protective sheet of Comparative Example 4 had a value exceeding the measurement limit.

[Test Example 2] (Measurement of haze value)

The release sheet was peeled off from the protective sheet prepared in Examples and Comparative Examples and the haze value of the obtained laminate was measured in accordance with JIS K7136: 2000 using a haze meter (manufactured by Nippon Denshoku Chemical Co., Ltd., product name "NDH7000" Respectively. The results are shown in Table 2.

[Test Example 3] (Measurement of adhesive force)

The protective sheet prepared in Examples and Comparative Examples was cut to a length of 100 mm and a width of 25 mm, and a release sheet was peeled off. The obtained test piece was attached to sodalime glass at a pressure of 0.5 MPa at 50 캜 for 20 minutes, and then left to stand under a standard environment (23 캜, 50% RH) for 24 hours. Thereafter, using a tensile tester (Orientech Co., Ltd., product name " Tensilon UTM-4-100 ") under a standard environment (23 ° C, 50% RH) in accordance with JIS Z0237: 2009, , And the protective sheet was peeled off at a peeling rate of 300 mm / min to measure the adhesive force (N / 25 mm). The results are shown in Table 2.

[Test Example 4] (Evaluation of substrate adhesion property)

The release sheet was peeled off from the protective sheet prepared in Examples and Comparative Examples, and a cross cut (50 mm x 50 mm) was inserted into the pressure-sensitive adhesive layer with a cutter knife. Then, the pressure-sensitive adhesive layer in the cut portion was rubbed with a finger to confirm the degree of detachment of the pressure-sensitive adhesive layer, and the adhesion of the base material was evaluated according to the following criteria. The results are shown in Table 2.

 Good: The pressure-sensitive adhesive layer is not detached from the substrate, and good adhesion is maintained

 DELTA: Part of the pressure-sensitive adhesive layer was detached from the base material, but a certain degree of adhesion was maintained

 X: The whole pressure-sensitive adhesive layer was detached from the base material, and the lack of adhesion

[Table 1]

[Table 2]

As is apparent from Table 2, the protective sheet produced in the Examples was excellent in antistatic property, high in transparency, and excellent in adhesion to the base material of the pressure-sensitive adhesive layer.

The protective sheet according to the present invention is suitable as a protective sheet used in processes such as processing, assembling, and inspection of an OLED device having flexibility.

1: Protective sheet
11: substrate
12: pressure-sensitive adhesive layer
13: Peeling sheet

Claims (8)

A silicone adhesive,
Antistatic agent
Wherein the antistatic silicone pressure-
Wherein the antistatic agent is an ionic compound comprising an anion and a cation,
Wherein the anion and the cation are both carbon atoms-free
≪ / RTI > The method according to claim 1,
The antistatic silicone pressure-sensitive adhesive composition according to claim 1, wherein the anion contains a fluorine atom. The method according to claim 1,
The antistatic silicone pressure-sensitive adhesive composition according to claim 1, wherein the cation is a metal cation. The method of claim 3,
The antistatic silicone pressure-sensitive adhesive composition according to claim 1, wherein the metal cation is an alkali metal. The method according to claim 1,
An antistatic agent, and a dispersant for dispersing the antistatic agent. 6. The method of claim 5,
Wherein the dispersant is an alkylene glycol dialkyl ether. A protective sheet for protecting a device,
A base film,
A pressure-sensitive adhesive layer laminated on one side of the base film
Respectively,
Wherein the pressure-sensitive adhesive layer is formed of the antistatic silicone pressure-sensitive adhesive composition according to any one of claims 1 to 6
Wherein the protective sheet is a sheet. 8. The method of claim 7,
Wherein the device is a flexible device.

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