JP6517451B2 - Method for producing double-sided silicone adhesive sheet - Google Patents

Description

  The present invention relates to a double-sided silicone pressure-sensitive adhesive sheet and a method for producing the double-sided silicone pressure-sensitive adhesive sheet.

Heat-resistant adhesive sheets using silicone-based pressure-sensitive adhesives are widely used in the manufacturing process of electronic devices.
For example, in patent document 1, the adhesive tape for electronic devices is produced by apply | coating an addition reaction type silicone adhesive with a platinum catalyst on the single side | surface of the polyimide film which is a heat resistant base material.
In Patent Document 2, an adhesive prepared by adding a two-component addition-curable silicone rubber containing a vinyl group and a hydrosilyl group in the main chain of dimethylsiloxane to a silicone-based adhesive is applied to a polyimide substrate layer and dried. Heat-resistant adhesive tape for semiconductor package manufacturing process.
In Patent Document 3, a silicone solution is formed by applying and heating a toluene solution containing an addition reaction type silicone pressure sensitive adhesive, a platinum type catalyst and dimethyl silicone oil on one surface of a polyimide film as a substrate. There is. Furthermore, a polyethylene terephthalate film is pasted together to a silicone type adhesion layer, and a pressure sensitive adhesive tape for surface protection is produced.
In the pressure-sensitive adhesive tapes of Patent Documents 1 to 3, a silicone-based pressure-sensitive adhesive layer is obtained by applying a solvent-based coating solution prepared by diluting a silicone-based pressure-sensitive adhesive with a solvent to a polyimide film as a heat resistant substrate and drying. Is formed on only one side of the substrate.

JP 2004-224857 A JP, 2012-151360, A JP, 2013-147540, A

In recent years, not only single-sided silicone pressure-sensitive adhesive sheets but also double-sided silicone pressure-sensitive adhesive sheets are required.
The double-sided silicone pressure-sensitive adhesive sheet is a method in which a release sheet is attached to a pressure-sensitive adhesive layer obtained through a drying step after the pressure-sensitive adhesive composition is directly applied to a substrate using a roll coater, die coater, etc. It can be manufactured by a method (hereinafter referred to as transfer method) in which the pressure-sensitive adhesive composition is once coated on a release sheet or a release sheet and the pressure-sensitive adhesive layer obtained through the drying step is transferred to a substrate. . The double-sided silicone pressure-sensitive adhesive sheet produced by the transfer method tends to have poorer adhesion between the pressure-sensitive adhesive layer and the substrate than the double-sided silicone pressure-sensitive adhesive sheet produced by the direct coating method. Therefore, it is preferable to obtain a double-sided silicone adhesive sheet using a direct coating method. Specifically, a single-sided silicone pressure-sensitive adhesive sheet is obtained by applying a silicone-based pressure-sensitive adhesive coating liquid to one surface (first substrate surface) of a substrate to form a first pressure-sensitive adhesive layer. . Thereafter, for example, the single-sided silicone pressure-sensitive adhesive sheet wound up in a roll shape is fed out, and a coating liquid of a silicone-based pressure-sensitive adhesive is applied to the other surface (second substrate surface) of the substrate to form a second pressure-sensitive adhesive layer Manufacture a double-sided silicone adhesive sheet by forming
However, when the double-sided silicone adhesive sheet was produced by the above method, it was confirmed that the charge amount of the single-sided silicone adhesive sheet was increased when the single-sided silicone adhesive sheet was fed. In the process of applying the coating liquid of silicone pressure sensitive adhesive to the second base material surface to form the second pressure sensitive adhesive layer, the static electricity of the single sided silicone pressure sensitive adhesive sheet generated at the time of feeding of the single sided silicone pressure sensitive adhesive sheet The organic solvent of the adhesive coating liquid may ignite and cause a fire.

  The object of the present invention is that in the process of producing a double-sided silicone adhesive sheet by the direct coating method, the organic solvent of the coating liquid of the silicone-based adhesive is ignited by the static electricity of the single-sided silicone adhesive sheet It is an object of the present invention to provide a method for producing a double-sided silicone adhesive sheet that can be safely produced without the risk of Another object of the present invention is to provide a highly safe double-sided silicone adhesive sheet in which the increase in charge amount is suppressed.

  According to one aspect of the present invention, a step of applying a first coating liquid containing a silicone-based pressure-sensitive adhesive to a first substrate surface of a substrate to form a first pressure-sensitive adhesive layer; A first release film is laminated on the first pressure-sensitive adhesive layer to obtain a single-sided silicone pressure-sensitive adhesive sheet having antistatic performance, a step of winding the single-sided silicone pressure-sensitive adhesive sheet into a roll, and Applying a second coating liquid containing a silicone-based pressure-sensitive adhesive to the step of feeding out the single-sided silicone pressure-sensitive adhesive sheet, and the second base material surface opposite to the first base material surface of the base material A method of producing a double-sided silicone pressure-sensitive adhesive sheet, comprising the steps of: forming a second pressure-sensitive adhesive layer; and laminating a second release film on the second pressure-sensitive adhesive layer and winding it in a roll. Provided.

  In the method for producing a double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the first coating liquid preferably contains an antistatic agent.

  In the method for producing a double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the antistatic agent contained in the first coating liquid is preferably an ion conductive silicone compound.

  In the method for producing a double-sided silicone adhesive sheet according to one aspect of the present invention, the antistatic agent contained in the first coating liquid is a silicone oil in which an ionic group-containing silicone oligomer or an alkali metal salt is dissolved. Is preferred.

  In the method for producing a double-sided silicone adhesive sheet according to an aspect of the present invention, the second coating liquid preferably contains an antistatic agent.

  In the method for producing a double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the substrate is preferably long (strip-like).

  In the method for producing a double-sided silicone adhesive sheet according to one aspect of the present invention, the substrate is preferably a polyimide film.

  In the method for producing a double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, a plurality of A4-sized test pieces are produced from the roll-shaped single-sided silicone pressure-sensitive adhesive sheet, and a plurality of the test pieces are stacked to produce a laminate. After taking out one test piece from the outermost layer of the laminate and taking out one test piece from the laminate, the charge amount of one test piece is 10 kV or less after a lapse of 60 seconds. Is preferred.

  Further, according to one aspect of the present invention, a base material having a first base material surface and a second base material surface opposite to the first base material surface, and the first base material surface A first pressure-sensitive adhesive layer provided on the substrate, a first release film laminated on the first pressure-sensitive adhesive layer, a second pressure-sensitive adhesive layer provided on the second substrate surface, and A second release film laminated on a second pressure-sensitive adhesive layer, the first pressure-sensitive adhesive layer and the second pressure-sensitive adhesive layer containing a silicone-based pressure-sensitive adhesive, and the first adhesion The agent layer is provided with a double-sided silicone adhesive sheet having antistatic performance.

  In the double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the base is preferably long (strip-like).

  In the double-sided silicone adhesive sheet according to one aspect of the present invention, the substrate is preferably a polyimide film.

  In the double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the first pressure-sensitive adhesive layer preferably contains an antistatic agent.

  In the double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the antistatic agent contained in the first pressure-sensitive adhesive layer is preferably an ion conductive silicone compound.

  In the double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the antistatic agent contained in the first pressure-sensitive adhesive layer is a silicone oil in which an ionic group-containing silicone oligomer or an alkali metal salt is dissolved. preferable.

  In the double-sided silicone pressure-sensitive adhesive sheet according to one aspect of the present invention, the second pressure-sensitive adhesive layer preferably contains an antistatic agent.

  According to the present invention, in the step of producing the double-sided silicone adhesive sheet by the direct coating method, the organic solvent of the coating liquid of the silicone-based adhesive is ignited by the static electricity of the single-sided silicone adhesive sheet generated when the single-sided silicone adhesive sheet is delivered. It is possible to provide a method for producing a double-sided silicone adhesive sheet that can be safely produced without the risk of Further, according to the present invention, it is possible to provide a highly safe double-sided silicone adhesive sheet in which an increase in the amount of charge is suppressed.

It is the cross-sectional schematic of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing apparatus of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing process of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing process of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing process of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing process of the double-sided silicone adhesive sheet which concerns on embodiment. It is a figure explaining a part of manufacturing process of the double-sided silicone adhesive sheet which concerns on embodiment. It is the cross-sectional schematic of the double-sided silicone adhesive sheet which concerns on the deformation | transformation of embodiment.

[Double-sided silicone adhesive sheet]
The cross-sectional schematic of the double-sided silicone adhesive sheet 1 of this embodiment is shown by FIG.
The double-sided silicone adhesive sheet 1 has a first base surface 11a and a second base surface 11b opposite to the first base surface 11a, and a first base surface 11a. The first pressure-sensitive adhesive layer 21 provided, the first release film 31 laminated on the first pressure-sensitive adhesive layer 21, and the second pressure-sensitive adhesive layer 22 provided on the second substrate surface 11b , And a second release film 32 laminated to the second pressure-sensitive adhesive layer 22.
The first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 contain a silicone-based pressure-sensitive adhesive.
The first pressure-sensitive adhesive layer 21 preferably contains an antistatic agent. Furthermore, the second pressure-sensitive adhesive layer 22 can also contain an antistatic agent.
The shape of the double-sided silicone pressure-sensitive adhesive sheet 1 can be any shape such as, for example, a sheet, a tape, or a label.

(Base material)
As the base material 11, sheet materials, such as a synthetic resin film, etc. can be used, for example. Examples of synthetic resin films include polyimide films, polyethylene films, polypropylene films, polybutene films, polybutadiene films, polymethylpentene films, polyvinyl chloride films, vinyl chloride copolymer films, polyethylene terephthalate films, polyethylene naphthalate films, and the like. Butylene terephthalate film, polyurethane film, ethylene vinyl acetate copolymer film, ionomer resin film, ethylene (meth) acrylic acid copolymer film, ethylene (meth) acrylic acid ester copolymer film, polystyrene film, and polycarbonate film Etc. In addition, as the base material 11, the crosslinked film of these synthetic resin films, laminated | multilayer film, etc. are mentioned. The substrate 11 may have antistatic properties.
From the viewpoint of heat resistance, the substrate 11 is preferably a polyimide film.
It is preferable that the base material 11 is elongate (strip | belt shape). By using the long base material 11, the long double-sided silicone adhesive sheet 1 can be manufactured, so that the so-called roll-to-roll production becomes possible, and the productivity of the double-sided silicone adhesive sheet 1 is improved. Do.
The thickness of the substrate 11 is preferably 10 μm to 500 μm, more preferably 15 μm to 300 μm, and still more preferably 20 μm to 250 μm.

(Pressure-sensitive adhesive layer)
The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 contains a silicone-based pressure-sensitive adhesive. The silicone-based pressure-sensitive adhesive contained in the pressure-sensitive adhesive composition of the first pressure-sensitive adhesive layer 21 and the silicone-based pressure-sensitive adhesive contained in the pressure-sensitive adhesive composition of the second pressure-sensitive adhesive layer 22 are mutually identical. May also be different.

The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer 21 preferably contains a silicone-based pressure-sensitive adhesive and an antistatic agent. Details of the antistatic agent will be described later.
The pressure-sensitive adhesive composition constituting the second pressure-sensitive adhesive layer 22 contains a silicone-based pressure-sensitive adhesive, may further contain an antistatic agent, and may not contain an antistatic agent.

  The thickness of each of the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 is preferably independently 1 μm to 100 μm, more preferably 2 μm to 80 μm, and more preferably 5 μm to 50 μm. Is more preferred. If the thickness of the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 is less than 1 μm, the adhesive force of the obtained pressure-sensitive adhesive tape may not be sufficient. On the other hand, when the thickness of the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 exceeds 100 μm, the adhesion performance is not improved and it is uneconomical. In addition, when the thickness of the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 exceeds 100 μm, there is a risk of causing the pressure-sensitive adhesive to stick out when the pressure-sensitive adhesive sheet is stuck, and the pressure-sensitive adhesive sheet is adhered. It may cause cohesive failure of the pressure-sensitive adhesive layer when peeled from the body.

-Silicone pressure sensitive adhesive As silicone pressure sensitive adhesive, the pressure sensitive adhesive containing an organopolysiloxane is mentioned, for example, and the pressure sensitive adhesive containing dimethylpolysiloxane is preferred. More specifically, as the silicone-based pressure-sensitive adhesive, an organopolysiloxane having an unsaturated group such as a vinyl group, preferably a dimethylpolysiloxane having an unsaturated group such as a vinyl group, a crosslinking containing a hydrosilyl group (SiH group) It is possible to use an agent, an addition reaction type silicone-based pressure-sensitive adhesive obtained by curing with a platinum-based catalyst, or a peroxide-curable silicone-based pressure-sensitive adhesive obtained by curing with an organic peroxide such as BPO. BPO is an abbreviation for benzoylperoxide. From the viewpoint of heat resistance, addition reaction type silicone pressure sensitive adhesives are preferable. In this case, it is possible to adjust the crosslink density in accordance with the density of the unsaturated group in consideration of the adhesion obtained. It is necessary to perform heating etc. in order to carry out addition polymerization for formation of this silicone type adhesive layer.

Antistatic Agent The antistatic agent is not particularly limited. As the antistatic agent, a compound which can be mixed with the silicone-based pressure-sensitive adhesive composition and uniformly dispersed in the silicone-based pressure-sensitive adhesive composition is preferable. For example, as the antistatic agent, an ion conductive antistatic agent, conductive fine particles and the like can be mentioned. Moreover, as another antistatic agent, an ion conductive silicone type compound is mentioned. The antistatic agent is preferably an ion conductive antistatic agent or an ion conductive silicone compound, and more preferably an ion conductive silicone compound. It does not specifically limit as an ion conductive silicone type compound. Examples of the ion conductive silicone compound include an ionic group-containing silicone oligomer, a silicone oil in which an alkali metal salt is dissolved, and an ionic group-containing silicone polymer. Among them, a silicone oil in which an ionic group-containing silicone oligomer or an alkali metal salt is dissolved is preferable from the viewpoint that the dispersibility with the silicone-based pressure-sensitive adhesive composition is good and the heat resistance and the antistatic property are also excellent. The ionic group-containing silicone oligomer is a silicone oligomer obtained by modifying an ionic liquid with silicone, and commercially available products include, for example, X-40-2750, X-40-2450, X-40- manufactured by Shin-Etsu Chemical Co., Ltd. 9310 and the like. As an alkali metal salt to be dissolved in silicone oil, a lithium salt is preferable. When the pressure-sensitive adhesive composition of the second pressure-sensitive adhesive layer 22 contains an antistatic agent, the antistatic agent (first antistatic agent) contained in the pressure-sensitive adhesive composition of the first pressure-sensitive adhesive layer 21 And the antistatic agent (sometimes referred to as a second antistatic agent) contained in the pressure-sensitive adhesive composition of the second pressure-sensitive adhesive layer 22 are identical to each other. May also be different.
The content of the antistatic agent is 0.1 mass based on the pressure-sensitive adhesive composition (when the pressure-sensitive adhesive composition is 100% by mass) constituting the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22. It is preferable that it is% or more and 50 mass% or less, and it is more preferable that it is 1.0 mass% or more and 40 mass% or less. The content of the first antistatic agent contained in the pressure-sensitive adhesive composition of the first pressure-sensitive adhesive layer 21 and the second antistatic agent contained in the pressure-sensitive adhesive composition of the second pressure-sensitive adhesive layer 22 The contents may be the same as or different from each other.

-Other components The pressure-sensitive adhesive composition constituting the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 may contain other components as long as the effects of the present invention are not impaired. As other components that may be contained in the pressure-sensitive adhesive composition, for example, flame retardants, tackifiers, UV absorbers, antioxidants, preservatives, mildewproofing agents, plasticizers, antifoaming agents, and wettability controlling agents Etc.

(Peeling film)
The first release film 31 and the second release film 32 are not particularly limited. For example, from the viewpoint of easy handling, the release film preferably includes a release substrate and a release agent layer formed by applying a release agent on at least one surface of the release substrate.
When the first release film 31 and the second release film 32 have a release substrate, the release substrate of the first release film 31 and the release substrate of the second release film 32 are identical to each other. It may be different or different.
When the first release film 31 and the second release film 32 have release agent layers, the release agent layer of the first release film 31 and the release agent layer of the second release film 32 have the same release. It may be formed of an agent, and may be formed of different release agents.
Examples of the release substrate include a paper substrate, a laminated paper obtained by laminating a thermoplastic resin such as polyethylene on the paper substrate, and a plastic film.
Paper substrates include glassine paper, coated paper, cast coated paper, and the like. Examples of the plastic film include polyester films such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate, and polyolefin films such as polypropylene and polyethylene.
Examples of the release agent include olefin resins, rubber elastomers (for example, butadiene resins, isoprene resins, etc.), long chain alkyl resins, alkyd resins, fluorine resins, and silicone resins. Among these, as the release agent, any one selected from the group consisting of an olefin resin, a rubber elastomer (for example, a butadiene resin, an isoprene resin, etc.), a long chain alkyl resin, an alkyd resin, and a fluorine resin It is preferable that it is a peeling agent, and it is more preferable that it is a fluorine resin. A release film using a general silicone resin has a problem that it is easily peeled off from the pressure-sensitive adhesive layer containing a silicone-based adhesive. Therefore, if the release agent layer of the first release film 31 and the second release film 32 is a fluorine-based resin, the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22 containing a silicone-based pressure-sensitive adhesive The double-sided silicone pressure-sensitive adhesive sheet 1 having good peelability can be obtained, which can suppress heavy peeling. The release agent layer may further contain an antistatic agent or may not contain an antistatic agent.

The thickness of the first release film 31 and the second release film 32 is not particularly limited. The thickness of the first release film 31 and the second release film 32 is preferably 20 μm or more and 200 μm or less, and more preferably 25 μm or more and 150 μm or less.
The thickness of the release agent layer is not particularly limited. When a solution containing a release agent is applied onto a release substrate to form a release agent layer, the thickness of the release agent layer is preferably 0.01 μm or more and 2.0 μm or less, and preferably 0.03 μm or more. More preferably, it is 0 μm or less.
When a plastic film is used as the release substrate, the thickness of the plastic film is preferably 3 μm to 50 μm, and more preferably 5 μm to 40 μm.

-Other layers The double-sided silicone pressure-sensitive adhesive sheet 1 is other than the substrate 11, the first pressure-sensitive adhesive layer 21, the first release film 31, the second pressure-sensitive adhesive layer 22, and the second release film 32; It may further comprise a layer.

[Method of producing double-sided silicone adhesive sheet]
The method to manufacture the double-sided silicone adhesive sheet 1 which concerns on this embodiment is demonstrated.
In the method for producing the double-sided silicone adhesive sheet 1 according to the present embodiment, a first coating liquid containing a silicone-based pressure-sensitive adhesive and an antistatic agent is applied to the first substrate surface 11 a of the substrate 11. A step of forming one pressure-sensitive adhesive layer 21, a step of laminating the first release film 31 on the first pressure-sensitive adhesive layer 21, and a second side of the substrate 11 opposite to the first substrate surface 11a. Applying a second coating liquid containing a silicone-based pressure-sensitive adhesive to the base surface 11b of the second layer to form a second pressure-sensitive adhesive layer 22, and a second peeling film on the second pressure-sensitive adhesive layer 22 And laminating 32 and winding up in a roll.

The first coating liquid and the second coating liquid can be prepared by diluting the silicone-based pressure-sensitive adhesive composition with an organic solvent.
Examples of the organic solvent include toluene, ethyl acetate, and methyl ethyl ketone. The method of applying the coating liquid is not particularly limited. Examples of the coating method include a spray coating method, a bar coating method, a knife coating method, a roll knife coating method, a roll coating method, a blade coating method, a die coating method, and a gravure coating method.
In order to prevent the organic solvent and the low boiling point components from remaining in the first pressure-sensitive adhesive layer 21 and the second pressure-sensitive adhesive layer 22, the coating solution is applied to the substrate 11 and then the coating is heated and dried. . Moreover, when a crosslinking agent is mix | blended with an adhesive composition, in order to advance a crosslinking reaction and to improve cohesive force, it is preferable to heat a coating film.

FIG. 2 is a schematic view illustrating an adhesive sheet manufacturing apparatus 100A of the double-sided silicone adhesive sheet 1 according to the present embodiment.
The adhesive sheet manufacturing apparatus 100A includes a first roll delivery unit 100, an application unit 200, a drying unit 300, a second roll delivery unit 400, a bonding unit 500, and a roll winding unit 600.
The 1st roll delivery part 100 delivers the base material 11 and the single-sided silicone adhesive sheet 10 (refer FIG. 3C) wound up by roll shape.
The application unit 200 applies the coating liquid to the base material 11 and the single-sided silicone adhesive sheet 10 fed by the first roll feeding unit 100 to form a pressure-sensitive adhesive layer.
The drying unit 300 dries the pressure-sensitive adhesive layer to remove the organic solvent and the like contained in the coating liquid.
The second roll delivery unit 400 delivers the release film wound up in a roll shape.
The bonding unit 500 laminates the release film fed from the second roll feeding unit 400 on the pressure-sensitive adhesive layer dried by the drying unit 300.
The roll winding unit 600 winds up the release film laminated sheet (single-sided silicone adhesive sheet 10 and double-sided silicone adhesive sheet 1) in a roll.

The schematic explaining the manufacturing method of the double-sided silicone adhesive sheet 1 which concerns on this embodiment is shown by FIG. 3A-FIG. 3E. In the present embodiment, a method of manufacturing using the pressure-sensitive adhesive sheet manufacturing apparatus 100A will be described as an example. Specifically, the double-sided silicone adhesive sheet 1 according to this embodiment is manufactured through the following steps.
In FIG. 3A, a cross-sectional schematic view of the substrate 11 having the first substrate surface 11a and the second substrate surface 11b is shown. In the present embodiment, first, the long base material 11 wound up in a roll shape is installed in the first roll delivery unit 100.
Next, the substrate 11 is fed out by the first roll feeding unit 100 so that the first substrate surface 11 a is on the upper surface, and is conveyed to the coating unit 200. The first coating liquid containing a silicone-based pressure-sensitive adhesive and an antistatic agent is applied to the first substrate surface 11 a of the substrate 11 in the application unit 200 to form the first pressure-sensitive adhesive layer 21 ( See Figure 3B). Thereafter, the first laminate having the substrate 11 and the first pressure-sensitive adhesive layer 21 is transported from the application unit 200 to the drying unit 300, and the first pressure-sensitive adhesive layer 21 is dried.
Furthermore, the first laminate is transported from the drying unit 300 to the bonding unit 500, and the first release film 31 is laminated on the first pressure-sensitive adhesive layer 21 (see FIG. 3C). The first peeling film 31 is a long film wound in a roll shape, and is fed from the second roll feeding unit 400 and conveyed to the bonding unit 500, and the bonding unit 500 It is bonded to one stack.
Thus, a second laminate (single-sided silicone pressure-sensitive adhesive sheet 10) provided with the first pressure-sensitive adhesive layer 21 between the substrate 11 and the first release film 31 is obtained (see FIG. 3C).
The manufacturing method which concerns on this embodiment has the process of winding up the single-sided silicone adhesive sheet 10 in roll shape, before forming the 2nd adhesive layer 22. As shown in FIG.
In the manufacturing method according to the present embodiment, the single-sided silicone adhesive sheet 10 wound up in a roll is further installed in the first roll delivery portion 100 of FIG. 2 so that the second base material surface 11b is on the upper surface. It has a process of delivering. The single-sided silicone adhesive sheet 10 thus fed is conveyed to the coating unit 200.
A second coating liquid containing a silicone-based pressure-sensitive adhesive is applied to the second base surface 11b of the single-sided silicone pressure-sensitive adhesive sheet 10 conveyed to the application unit 200 to form a second pressure-sensitive adhesive layer 22 (see FIG. See Figure 3D). Thereafter, the third laminate (the laminate having the base 11, the first pressure-sensitive adhesive layer 21, the first peeling film 31 and the second pressure-sensitive adhesive layer 22) is conveyed from the application unit 200 to the drying unit 300. , And the second pressure-sensitive adhesive layer 22 is dried.
Furthermore, the third laminated body is conveyed from the drying unit 300 to the bonding unit 500, and the second peelable film 32 is laminated on the second pressure-sensitive adhesive layer 22 (see FIG. 3E). The second peeling film 32 is a long film wound in a roll shape, and is fed from the second roll feeding unit 400 and conveyed to the bonding unit 500, and the bonding unit 500 It is pasted together with three laminated bodies.
Thus, the first pressure-sensitive adhesive layer 21 is provided between the substrate 11 and the first release film 31, and the second pressure-sensitive adhesive layer 22 is provided between the substrate 11 and the second release film 32. A double-sided silicone pressure-sensitive adhesive sheet 1 is provided (see FIG. 3E).
The double-sided silicone adhesive sheet 1 manufactured in this manner is, for example, wound in a roll at a roll winding unit 600 in FIG.

  The double-sided silicone adhesive sheet 1 which concerns on this embodiment can be manufactured using 100 A of adhesive sheet manufacturing apparatuses. The present invention is not limited to the double-sided silicone pressure-sensitive adhesive sheet 1 produced using the pressure-sensitive adhesive sheet production apparatus 100A and the method for producing the double-sided silicone pressure-sensitive adhesive sheet 1 implemented using the pressure-sensitive adhesive sheet production apparatus 100A.

  From the viewpoint of obtaining adhesion between the silicone-based pressure-sensitive adhesive and the base material 11, the first coating liquid and the second coating liquid are directly applied to the base material 11 to form a first pressure-sensitive adhesive layer It is preferable to form 21 and the 2nd adhesive layer 22. FIG.

  The charge amount of the single-sided silicone pressure-sensitive adhesive sheet 10 is preferably 10 kV or less. In addition, the charge amount of the single-sided silicone adhesive sheet 10 is the value measured by the method of the below-mentioned Example. If the said charge amount of the single-sided silicone adhesive sheet 10 is 10 kV or less, there is no possibility of ignition and the second adhesive composition can be applied by the direct coating method.

[Effect of the embodiment]
According to the method for producing a double-sided silicone pressure-sensitive adhesive sheet according to the present embodiment, in the step of producing the double-sided silicone pressure-sensitive adhesive sheet by the direct coating method, when the single-sided silicone pressure-sensitive adhesive sheet is delivered, There is no possibility that the organic solvent of the coating liquid will ignite, and the double-sided silicone adhesive sheet can be manufactured safely.

The double-sided silicone pressure-sensitive adhesive sheet according to the present embodiment can be used as a highly safe double-sided silicone pressure-sensitive adhesive sheet in which the increase in the charge amount is suppressed.
Moreover, the double-sided silicone adhesive sheet which concerns on this embodiment can be utilized as a double-sided silicone adhesive sheet containing a heat resistant silicone type adhesive. The double-sided silicone adhesive sheet according to the present embodiment can be suitably used, for example, in the process of manufacturing an electronic device that requires high temperature conditions. Furthermore, in the double-sided silicone pressure-sensitive adhesive sheet according to the present embodiment, by using a heat-resistant polyimide film as a substrate, it can be more suitably used in the manufacturing process of the electronic device.

[Modification of the embodiment]
The present invention is not limited to the above embodiment. The present invention includes the modes etc. which changed the above-mentioned embodiment in the range which can achieve the object of the present invention.

As another aspect of the double-sided silicone pressure-sensitive adhesive sheet, as shown in FIG. 4, the base material 11, the first pressure-sensitive adhesive layer 21 provided on the first base material surface 11 a, and the first pressure-sensitive adhesive layer 21 and a second pressure-sensitive adhesive layer 22 provided on the second base material surface 11b, and the second pressure-sensitive adhesive layer 22 is provided with a second release film 32. The double-sided silicone adhesive sheet 1A which is not laminated | stacked is mentioned. The double-sided peeling film 33 has peelability on both sides. The double-sided peeling film 33 preferably includes a peeling substrate and a peeling agent layer formed on both sides of the peeling substrate. The release substrate and the release agent layer of the double-sided release film 33 may be the same release substrate and release agent layer as the first release film 31 and the second release film 32.
When the double-sided silicone adhesive sheet 1A has a sheet-like shape, a plurality of double-sided silicone adhesive sheets 1A may be laminated to form a laminate. In this laminate, the second adhesive layer 22 of another double-sided silicone adhesive sheet 1A can be laminated on the outer surface side of the double-sided peelable film 33 of the double-sided silicone adhesive sheet 1A. By setting it as such a lamination state, the sheet-like double-sided silicone adhesive sheet 1A can be peeled off one by one from the laminate while protecting the second pressure-sensitive adhesive layer 22.
When the double-sided silicone adhesive sheet 1A is long, it can be wound around a core material and stored as a roll.

  In the embodiment, as a method of obtaining a single-sided silicone adhesive sheet having antistatic performance, a first coating liquid containing a silicone-based adhesive and an antistatic agent is applied to form a first adhesive layer. Although the method has been described by way of example, the invention is not limited to such an embodiment. Examples of the single-sided silicone adhesive sheet having antistatic performance include the following.

The first embodiment includes a single-sided silicone adhesive sheet in which the substrate is a substrate having antistatic properties (antistatic substrate). As a modification of this first embodiment, the first pressure-sensitive adhesive layer is a single-sided silicone pressure-sensitive adhesive sheet containing no antistatic agent, or the first pressure-sensitive adhesive layer further contains an antistatic agent. Can be mentioned. In the first aspect and the modification of the first aspect, the first release film may have antistatic properties or may not have antistatic properties.
As a method of forming a pressure-sensitive adhesive layer not containing an antistatic agent, for example, a method of preparing a coating liquid not containing an antistatic agent and applying the coating liquid to a substrate and drying it Can be mentioned.

A second embodiment includes a single-sided silicone adhesive sheet having an antistatic layer on at least one of the first substrate surface and the opposite second substrate surface of the substrate. When the antistatic layer is formed on the first substrate surface, the first pressure-sensitive adhesive layer is formed on the antistatic layer. When the antistatic layer is formed on the second substrate surface, the first pressure-sensitive adhesive layer is formed on the first substrate surface, and the second pressure-sensitive adhesive layer is formed on the antistatic layer. It is formed. As a modification of the second embodiment, the first pressure-sensitive adhesive layer is a single-sided silicone pressure-sensitive adhesive sheet not containing an antistatic agent, or the single-sided silicone pressure-sensitive adhesive sheet further containing an antistatic agent. It can be mentioned.
In the second aspect and the modification of the second aspect, the substrate may have antistatic properties or may not have antistatic properties. Further, in the second aspect and the modification of the second aspect, the first release film may have antistatic properties or may not have antistatic properties.

  A third aspect includes a single-sided silicone adhesive sheet in which a first release film having antistatic properties is laminated on a first adhesive layer. The first release film having antistatic properties is a release film provided with a release substrate and a release agent layer like the release film described in the above embodiment, and at least one of the release substrate and the release agent layer. It is preferred that the release film has an antistatic property. As a case where a release agent layer has antistatic property, the case where the antistatic agent is added to the release agent layer is mentioned, for example. As a modification of the third embodiment, a single-sided silicone pressure-sensitive adhesive sheet in which the first pressure-sensitive adhesive layer does not contain an antistatic agent, or a single-sided silicone pressure-sensitive adhesive sheet in which the first pressure-sensitive adhesive layer further contains an antistatic agent is It can be mentioned. In variants of the third aspect and the third aspect, the substrate may have antistatic properties or may not have antistatic properties.

  A fourth aspect includes a single-sided silicone pressure-sensitive adhesive sheet in which the silicone-based pressure-sensitive adhesive contained in the first pressure-sensitive adhesive layer has antistatic properties. In the case of the fourth aspect, even though the first pressure-sensitive adhesive layer does not contain an antistatic agent, the first pressure-sensitive adhesive layer has antistatic performance. As a silicone type adhesive which has antistatic property, the addition reaction type silicone type adhesive which has an ionic group is mentioned. In the fourth aspect, the substrate may have antistatic properties or may not have antistatic properties. In the fourth aspect, the first release film may have antistatic properties or may not have antistatic properties.

[Preparation of pressure-sensitive adhesive composition]

(1) Pressure-sensitive adhesive composition A
Addition reaction type silicone pressure sensitive adhesive (Toray Dow Corning Co., Ltd. product name: SD4570PSA, solid content 60 mass%, silicone resin content 60 mass%, addition reaction type silicone containing a crosslinking agent) 100 mass Part, a platinum catalyst (Toray Dow Corning Co., Ltd. product name: SRX-212, solid content 100% by mass) 0.9 parts by mass, and silicone oil in which lithium (Li) salt as an antistatic agent is dissolved 20 parts by mass (manufactured by Marubishi Yuka Kogyo Co., Ltd., PC-3462, solid content 62% by mass) is added to prepare an adhesive composition A, and this adhesive composition A is diluted with toluene to obtain a solid content A coating liquid AL having a concentration of 25% by mass was prepared.

(2) Pressure-sensitive adhesive composition B
The antistatic agent contained in the pressure-sensitive adhesive composition A is changed to an ionic group-containing silicone oligomer (Shin-Etsu Chemical Co., Ltd., X-40-2750, solid content 100 mass%), and the addition amount is 6 mass parts. A pressure-sensitive adhesive composition B was prepared in the same manner as the pressure-sensitive adhesive composition A except that it was prepared to be as described above. The pressure-sensitive adhesive composition B was diluted with toluene to prepare a coating liquid BL having a solid content concentration of 25% by mass.

(3) Pressure-sensitive adhesive composition C
A pressure-sensitive adhesive composition C was prepared in the same manner as the pressure-sensitive adhesive composition A except that the antistatic agent contained in the pressure-sensitive adhesive composition A was not contained. The pressure-sensitive adhesive composition C was diluted with toluene to prepare a coating liquid CL having a solid content concentration of 25% by mass.

[Preparation of double-sided silicone adhesive sheet]

Example 1
With respect to the first substrate surface of a polyimide film (Toray DuPont Co., Ltd., Kapton 100H, thickness 25 μm) which is a substrate, the prepared coating liquid AL is dried to have a thickness of 20 μm. Apply using a comma coater (registered trademark), pass through a drying oven, dry at a wind speed of 5 m / sec, a drying temperature of 120 ° C, a drying time of 60 seconds, and further from a 38 μm polyethylene terephthalate film provided with a fluorine-based release layer The release layer side of the release film (Lintech Co., Ltd .; SP-PET 38 YSD) was laminated to prepare a single-sided silicone adhesive sheet having the structure of base material / first pressure-sensitive adhesive layer / first release film. The single-sided silicone adhesive sheet was wound into a roll. Moreover, the below-mentioned antistatic performance was evaluated using this single-sided silicone adhesive sheet.
Next, the single-sided silicone pressure-sensitive adhesive sheet is unrolled from the obtained single-sided silicone pressure-sensitive adhesive sheet winding body, and the prepared coating liquid CL is dried on the second substrate surface of the substrate using a comma coater (registered trademark). It is applied so that the thickness after it will be 20 μm, passed through a drying furnace, dried at wind speed 5 m / sec, drying temperature 120 ° C., drying time 60 seconds, and further from a 38 μm polyethylene terephthalate film provided with a fluorine-based release layer The release layer side of the release film [Lintech Co., Ltd .; SP-PET 38 YSD] is laminated, wound into a roll, and the second release film / second pressure-sensitive adhesive layer / substrate / first pressure-sensitive adhesive layer A double-sided silicone pressure-sensitive adhesive sheet having a constitution of the first release film was prepared.

(Example 2)
The single-sided silicone pressure-sensitive adhesive sheet and the double-sided silicone pressure-sensitive adhesive sheet of Example 2 were produced in the same manner as Example 1 except that the coating liquid AL in Example 1 was changed to the coating liquid BL. The evaluation of antistatic performance described later was carried out using this single-sided silicone adhesive sheet.

(Comparative example 1)
The comparative example 1 produced the single-sided silicone adhesive sheet like Example 1 except having changed the coating liquid AL in Example 1 into the coating liquid CL. Since static electricity was generated in the step of feeding the single-sided silicone adhesive sheet winding body, it was determined that there was a possibility of ignition, and the subsequent steps were stopped. The evaluation of the antistatic performance described later was performed on a single-sided silicone adhesive sheet.

[Evaluation of antistatic performance]
The charge amount of the single-sided silicone adhesive sheet was measured by the method described below.
In each of Examples and Comparative Examples, a plurality of A4 size test pieces were produced from the roll-shaped single-sided silicone adhesive sheet obtained. A plurality of test pieces were stacked to produce a laminate. The laminate was allowed to stand, then, one test piece was taken out from the outermost layer of the laminate, and the charge amount of one test piece was measured 60 seconds after the test piece was taken out from the laminate. The charge amount was measured by a digital electrostatic potential measuring device (KSD-0108, manufactured by Kasuga Denki Co., Ltd.). The A4 size means that the size is 210 mm long and 297 mm wide.

  Table 1 shows the evaluation results of the above-described antistatic performance of the test pieces according to Example 1, Example 2, and Comparative Example 1. The content of the antistatic agent in Table 1 is the content in the total solid content of the pressure-sensitive adhesive composition.

  The single-sided silicone adhesive sheet according to the example in which the first adhesive layer contains an antistatic agent has a small charge amount, and in the process of producing the double-sided silicone adhesive sheet by the direct coating method, the single-sided silicone adhesive sheet is single-sided There is no possibility that the organic solvent of the coating liquid of the silicone pressure sensitive adhesive will ignite due to the static electricity of the silicone pressure sensitive adhesive sheet, and the double-sided silicone pressure sensitive adhesive sheet can be manufactured safely.

  DESCRIPTION OF SYMBOLS 1 ... Double-sided silicone adhesive sheet, 11 ... Base material, 11a ... 1st base material surface, 11b ... 2nd base material surface, 21 ... 1st adhesive layer, 22 ... 2nd adhesive layer, 31 ... First release film, 32: second release film, 33: double-sided release film.

Claims (8)

Applying a first coating solution containing a silicone-based pressure-sensitive adhesive to a first substrate surface of the substrate to form a first pressure-sensitive adhesive layer;
Laminating a first release film on the first pressure-sensitive adhesive layer to obtain a single-sided silicone pressure-sensitive adhesive sheet having antistatic performance;
Winding the single-sided silicone adhesive sheet into a roll;
Delivering the single-sided silicone adhesive sheet rolled up in a roll;
A second coating liquid containing a silicone-based pressure-sensitive adhesive is applied to a second base material surface opposite to the first base material surface of the base material to form a second pressure-sensitive adhesive layer Process,
And laminating the second peelable film on the second pressure-sensitive adhesive layer and rolling it up in a roll. In the method of producing a double-sided silicone adhesive sheet according to claim 1,
The method for producing a double-sided silicone pressure-sensitive adhesive sheet, wherein the first coating liquid contains an antistatic agent. In the manufacturing method of the double-sided silicone adhesive sheet according to claim 2,
The manufacturing method of the double-sided silicone adhesive sheet whose said antistatic agent which said 1st coating liquid contains is an ion conductive silicone type compound. In the manufacturing method of the double-sided silicone adhesive sheet according to claim 2,
The method for producing a double-sided silicone adhesive sheet, wherein the antistatic agent contained in the first coating liquid is a silicone oil in which an ionic group-containing silicone oligomer or an alkali metal salt is dissolved. In the manufacturing method of the double-sided silicone adhesive sheet as described in any one of Claims 1-4,
The method of producing a double-sided silicone pressure-sensitive adhesive sheet, wherein the second coating liquid contains an antistatic agent. In the manufacturing method of the double-sided silicone adhesive sheet as described in any one of Claims 1-5,
The method for producing a double-sided silicone pressure-sensitive adhesive sheet, wherein the substrate is long. In the manufacturing method of the double-sided silicone adhesive sheet as described in any one of Claims 1-6,
The method for producing a double-sided silicone adhesive sheet, wherein the substrate is a polyimide film. In the manufacturing method of the double-sided silicone adhesive sheet as described in any one of Claim 1 to 7,
A plurality of A4-sized test pieces are prepared from the roll-shaped single-sided silicone adhesive sheet, and a plurality of the test pieces are stacked to form a laminate, and the test piece of one sheet is prepared from the outermost layer of the laminate. The manufacturing method of the double-sided silicone adhesive sheet whose charge amount of one said test piece after taking out and taking out one said test piece from the said laminated body after 60 seconds is 10 kV or less.

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