JP2010209190A - Pressure sensitive adhesive sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pressure sensitive adhesive sheet, on the adhesive layer face of which a separator having a irregular structure on a releasing agent layer surface is applied using a method of high productivity, that can continuously demonstrate peeling antistatic property to suppress generation of electrostatic due to peeling the separator. <P>SOLUTION: This pressure sensitive adhesive sheet includes an adhesive layer containing an adhesive composition, and a separator on at least one face of the adhesive layer. In the adhesive sheet, an irregular structure face of the releasing agent layer of the separator is applied to the adhesive layer face. The adhesive composition contains an ionic liquid, and a polymer having a glass transition temperature (Tg) of ≤0°C as a base polymer. The irregular structure surface of the releasing agent layer is formed by: forming water droplets on at least one surface of a separator base material; coating an organic solvent solution containing the releasing agent on the face of the separator base material having the formed water droplets; subsequently removing the organic solvent and the water droplets 2; and drying and/or curing the releasing agent. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention is a pressure-sensitive adhesive sheet in which a separator having a concavo-convex shape (concavo-convex structure) is adhered to the surface of a pressure-sensitive adhesive layer, and the pressure-sensitive adhesive sheet can suppress the generation of static electricity due to peeling of the separator. About. The pressure-sensitive adhesive sheet of the present invention is suitably used in plastic products that are prone to generate static electricity, electronic devices that dislike static electricity, scenes where dust or the like does not adhere due to static electricity, and the like.

  The pressure-sensitive adhesive sheet can be bonded by applying a slight pressure at room temperature for a short time, and thus is used in various applications in joining various articles. For example, in an optical application, a panel of a liquid crystal display is formed by attaching an optical member such as a polarizing plate or a wave plate to a liquid crystal cell via an adhesive. Furthermore, while the pressure-sensitive adhesive sheet adheres appropriately, it can be peeled off again from a hard, smooth surface, and is also used as a surface protective film. More specific usage modes include functional film, conductive film, surface protective film, double-sided pressure-sensitive adhesive sheet coated with adhesive on both sides of the support, and double-sided pressure-sensitive adhesive sheet without a support. And the like, and the like.

  In many cases, a separator or the like is used for the purpose of protecting the pressure-sensitive adhesive layer. The separator is a sheet in which a release agent such as silicone is applied to at least one surface of a substrate such as paper, plastic film, plastic laminate paper, etc., and dried and / or cured to provide a release agent layer. In order to protect the surface of the pressure-sensitive adhesive layer such as a tape or a label, it is used by being stuck to the surface of the pressure-sensitive adhesive layer, and is peeled off when being stuck to an adherend such as an optical member.

  In general, since the separator and the optical member are made of a plastic material, they have high electrical insulation and are likely to generate static electricity due to friction and peeling. When the separator is peeled off from the optical member such as a polarizing plate, the adhesive sheet, and the surface protective film, static electricity (peeling charge) is generated, and when voltage is applied to the liquid crystal while the static electricity remains, the alignment of the liquid crystal molecules Loss or panel loss, and such static electricity causes dust and dirt to adhere to the adhesive surface and contaminates the optical member. Therefore, various antistatic treatments are performed to prevent such problems. However, the conventional antistatic treatment has a problem that the antistatic effect decreases with time.

  On the other hand, as a separator having a fine uneven shape on the surface of the release agent layer, a pressure-sensitive adhesive sheet (for example, a sheet-like or tape-like form such as a pressure-sensitive adhesive sheet or a label) is attached between the adherend and the adherend. Forming a microstructured surface (a surface with a microstructure) on the surface of the adhesive layer of the adhesive sheet in order to prevent air bubbles from occurring and to facilitate re-attachment and correction of the application position It has been proposed that it is known that a fine uneven shape of a separator is used as a mold for forming these fine structures (see Patent Documents 1 to 3). In some cases, a separator having a fine concavo-convex structure is used to adjust the peeling force (see Patent Document 4).

  Several methods are known as methods for imparting fine irregularities to the surface of the release agent layer of the separator, but the conventional methods have the following problems. That is, in the method of applying a release agent to a substrate having a concavo-convex shape on the surface, it is difficult to apply the release agent with a uniform thickness, and unevenness in the thickness of the release agent layer is likely to occur. It was difficult to obtain a peeling force. In addition, in the method of providing a concavo-convex shape in a post-process to a separator provided with a release agent layer on a base material, the step of providing a release agent layer and the step of forming the concavo-convex shape are required separately, or the concavo-convex shape is formed. The process to perform is generally shape transfer with a heated roll, and the speed is slow and there is a problem in terms of productivity. Further, the method of applying the silicone twice to give the uneven shape also requires two coating steps, resulting in poor productivity.

JP 2003-145660 A JP-T-2004-506777 JP 2006-070273 A JP 2005-171030 A

  Accordingly, an object of the present invention is a pressure-sensitive adhesive sheet in which a separator having excellent productivity and having a stable peeling force is adhered to the pressure-sensitive adhesive layer surface, and prevents the occurrence of static electricity due to peeling of the separator. An object of the present invention is to provide a pressure-sensitive adhesive sheet that can continuously exhibit the properties.

  As a result of intensive studies to solve the above problems, the present inventors formed water droplets on at least one surface of the separator substrate, and then applied an organic solvent solution of a release agent on the water droplet formation surface of the separator substrate. Applying, then removing organic solvent and water droplets, drying and / or curing the release agent, can efficiently form an uneven shape on the surface of the release agent layer of the separator, and exhibits a stable release force It has been found that a separator that can be obtained can be obtained. Furthermore, the pressure-sensitive adhesive sheet having a pressure-sensitive adhesive layer containing an ionic liquid and a polymer having a specific glass transition temperature is excellent in antistatic property and pressure-sensitive adhesive strength. When the separator is attached to the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, an adherend is obtained. It has been found that even if the separator is peeled off when the adhesive sheet is attached to the sheet, it is possible to prevent the generation of static electricity and that the antistatic property does not disappear over time because the ionic liquid is non-volatile. Completed the invention.

  That is, the present invention provides at least one side of an adhesive layer made of an adhesive composition containing an ionic liquid and a polymer having a glass transition temperature (Tg) of 0 ° C. or less as a base polymer, and at least on one side of a separator substrate. After forming the water droplets, an organic solvent solution containing a release agent is applied to the surface of the separator substrate on which the water droplets are formed. Subsequently, the organic solvent and the water droplets are removed, and the release agent is dried and / or removed. Provided is a pressure-sensitive adhesive sheet in which a separator that has been cured to form a release agent layer with a concavo-convex shape on its surface is bonded so that the release agent layer with the concavo-convex shape is on the pressure-sensitive adhesive layer side .

  In the pressure-sensitive adhesive sheet, the method for forming water droplets is preferably either a method for condensing the substrate surface by humidification or a method for spraying water.

  As the release agent, a thermosetting addition type silicone release agent is preferable.

The ionic liquid is preferably at least one selected from a nitrogen-containing onium salt, a sulfur-containing onium salt, or a phosphorus-containing onium salt, and in particular, selected from cations represented by the following formulas (A) to (D) It is preferable to include one or more of the above.
[In the formula (A), R ^a represents a hydrocarbon group having 4 to 20 carbon atoms and may contain a heteroatom, and R ^b and R ^c may be the same or different and each may represent hydrogen or carbon number 1 Represents 16 hydrocarbon groups and may contain heteroatoms. However, when the nitrogen atom contains a double bond, there is no R ^c .
In the formula (B), R ^d represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a hetero atom, and R ^e , R ^f, and R ^g are the same or different and represent hydrogen or carbon number. It represents 1 to 16 hydrocarbon groups and may contain heteroatoms.
In the formula (C), R ^h represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a hetero atom, and R ⁱ , R ^j and R ^k may be the same or different and each represents hydrogen or carbon number. It represents 1 to 16 hydrocarbon groups and may contain heteroatoms.
In formula (D), Z represents a nitrogen, sulfur, or phosphorus atom, R ¹ , R ^m , R ⁿ , and R ^o are the same or different and each represents a hydrocarbon group having 1 to 20 carbon atoms; It may contain atoms. However, when Z is a sulfur atom, there is no R ^o ]

  The polymer having a glass transition temperature (Tg) of 0 ° C. or lower is preferably an acrylic polymer mainly composed of (meth) acrylate having an alkyl group having 1 to 14 carbon atoms.

  The pressure-sensitive adhesive sheet of the present invention can be used as a surface protective film.

  The present invention also provides at least one side of an adhesive layer made of an adhesive composition containing a polymer having a glass transition temperature (Tg) of 0 ° C. or less as an ionic liquid and a base polymer, and at least on one side of a separator substrate. After forming the water droplets, an organic solvent solution containing a release agent is applied to the surface of the separator substrate on which the water droplets are formed. Subsequently, the organic solvent and the water droplets are removed, and the release agent is dried and / or removed. A pressure-sensitive adhesive sheet comprising a separator formed by curing and forming a release agent layer having a concavo-convex shape on a surface thereof, the release agent layer having a concavo-convex shape being bonded to the pressure-sensitive adhesive layer side. A manufacturing method is provided.

  The pressure-sensitive adhesive sheet of the present invention uses a separator having an uneven shape on the surface of the release agent layer. The separator can be efficiently produced because it is produced by a method of imparting a concavo-convex shape to the surface of the release agent layer in the process of drying and / or curing the release agent, and a uniform release agent layer by the production method. Can be formed, and stable releasability can be exhibited. In addition, since the adhesive layer contains a polymer having a glass transition temperature (Tg) of 0 ° C. or less as a base polymer, the adherend can be held with excellent adhesive force, and a non-volatile ionic liquid can be used. Since it contains, it is possible to neutralize the bias of the charge generated by the separation of the separator, and to continuously exhibit excellent antistatic properties. Therefore, the pressure-sensitive adhesive sheet according to the present invention in which the separator is bonded to the pressure-sensitive adhesive layer is excellent in productivity and can prevent generation of static electricity even if the separator is peeled off when bonded to the adherend. . The pressure-sensitive adhesive sheet according to the present invention can be suitably used for optical applications that dislike dust, for example, for applications in which a liquid crystal cell is bonded to an optical member such as a polarizing plate or a wave plate in a panel of a liquid crystal display, or for surface protection films.

It is a schematic sectional drawing which shows an example of the state after completion | finish of the process which forms a water droplet on the at least one surface of a separator base material. It is a schematic sectional drawing which shows an example of the state after completion | finish of the process of apply | coating a releasing agent solution to a water drop formation surface and forming a releasing agent application layer. It is a schematic sectional drawing which shows an example of the state before the drying of the process of removing an organic solvent and a water droplet, drying and / or hardening a release agent, and forming the release agent processing layer which has an uneven | corrugated shape on the surface. It is a schematic sectional drawing which shows an example of the parator of this invention. It is a laser micrograph which shows the 2D image in the release agent process layer surface of a separator (1). It is a laser micrograph which shows the 3D image in the release agent processing layer surface of a separator (1). It is a laser micrograph which shows the 2D image in the release agent processing layer surface of a separator (2). It is a laser micrograph which shows the 3D image in the release agent processing layer surface of a separator (2). It is a laser micrograph which shows the 2D image in the release agent processing layer surface of a separator (3). It is a laser micrograph which shows the 3D image in the release agent process layer surface of a separator (3).

  The pressure-sensitive adhesive sheet according to the present invention has at least one surface of a separator substrate on at least one surface side of a pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive composition containing an ionic liquid and a polymer having a glass transition temperature (Tg) of 0 ° C. or less as a base polymer. After forming water droplets on the side, an organic solvent solution containing a release agent is applied on the surface of the separator substrate on which water droplets have been formed, followed by removing the organic solvent and water droplets, drying the release agent, and A separator having a release agent layer having a concavo-convex shape formed on the surface by curing is provided. The pressure-sensitive adhesive sheet may be a single-sided pressure-sensitive adhesive sheet having only one surface that is a pressure-sensitive adhesive surface, or may be a double-sided pressure-sensitive adhesive sheet having both surfaces that are pressure-sensitive adhesive surfaces. Moreover, the adhesive sheet of a base materialless type which consists only of an adhesive layer may be sufficient, and the adhesive sheet with a base material which has an adhesive layer in the at least single side | surface side of a base material may be sufficient.

[Adhesive composition]
The pressure-sensitive adhesive composition of the present invention contains a polymer having a glass transition temperature (Tg) of 0 ° C. or less as an ionic liquid and a base polymer.

(Ionic liquid)
An ionic liquid refers to a molten salt (ionic compound) that exhibits a liquid state at 25 ° C. Details of the reason why excellent antistatic properties can be obtained by using an ionic liquid are not clear, but are presumed as follows. That is, since the ionic liquid is in a liquid state, the molecular movement is easier than that of a commonly used surfactant, and molecular rearrangement is likely to occur when a charge bias occurs. Therefore, when an ionic liquid is used, it is considered that an excellent antistatic effect can be obtained because a charge neutralization mechanism by molecular rearrangement works. Moreover, since the ionic liquid is liquid at room temperature, it can be easily added to, dispersed in, or dissolved in the pressure-sensitive adhesive as compared with a solid salt. Furthermore, since the ionic liquid has no vapor pressure (non-volatile), it does not disappear with time and has a characteristic that antistatic properties can be obtained continuously.

  The ionic liquid of the present invention is preferably a nitrogen-containing onium salt, a sulfur-containing onium salt or a phosphorus-containing onium salt, and is represented by the above general formulas (A) to (D) for the reason that particularly excellent antistatic ability is obtained. A salt comprising an organic cation component and an anion component is preferably used.

  Examples of the cation represented by the formula (A) include a pyridinium cation, a piperidinium cation, a pyrrolidinium cation, a cation having a pyrroline skeleton, and a cation having a pyrrole skeleton. Specific examples include, for example, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-butyl-3-methylpyridinium cation, 1-butyl-4-methylpyridinium cation, 1-hexyl-3. -Pyridinium cations such as methylpyridinium cation and 1-butyl-3,4-dimethylpyridinium cation; 1-propylpiperidinium cation, 1-pentylpiperidinium cation, 1,1-dimethylpiperidinium cation, 1-methyl -1-ethylpiperidinium cation, 1-methyl-1-propylpiperidinium cation, 1-methyl-1-butylpiperidinium cation, 1-methyl-1-pentylpiperidinium cation, 1-methyl-1 -Hexyl piperidinium Cation, 1-methyl-1-heptylpiperidinium cation, 1-ethyl-1-propylpiperidinium cation, 1-ethyl-1-butylpiperidinium cation, 1-ethyl-1-pentylpiperidinium cation, 1-ethyl-1-hexylpiperidinium cation, 1-ethyl-1-heptylpiperidinium cation, 1,1-dipropylpiperidinium cation, 1-propyl-1-butylpiperidinium cation, 1,1- Piperidinium cations such as dibutylpiperidinium cation; 1,1-dimethylpyrrolidinium cation, 1-methyl-1-ethylpyrrolidinium cation, 1-methyl-1-propylpyrrolidinium cation, 1-methyl- 1-butylpyrrolidinium cation, 1-methyl-1-pentylpyrrolidi Cation, 1-methyl-1-hexylpyrrolidinium cation, 1-methyl-1-heptylpyrrolidinium cation, 1-ethyl-1-propylpyrrolidinium cation, 1-ethyl-1-butylpyrrolidinium cation, 1-ethyl-1-pentylpyrrolidinium cation, 1-ethyl-1-hexylpyrrolidinium cation, 1-ethyl-1-heptylpyrrolidinium cation, 1,1-dipropylpyrrolidinium cation, 1-propyl Pyrrolidinium cations such as -1-butylpyrrolidinium cation and 1,1-dibutylpyrrolidinium cation; 2-methyl-1-pyrroline cation, 1-ethyl-2-phenylindole cation, 1,2-dimethylindole A cation, 1-ethylcarbazole cation, etc. are mentioned.

  Examples of the cation represented by the formula (B) include an imidazolium cation, a tetrahydropyrimidinium cation, and a dihydropyrimidinium cation. Specific examples include, for example, 1,3-dimethylimidazolium cation, 1,3-diethylimidazolium cation, 1-ethyl-3-methylimidazolium cation, 1-butyl-3-methylimidazolium cation, 1-hexyl. -3-methylimidazolium cation, 1-octyl-3-methylimidazolium cation, 1-decyl-3-methylimidazolium cation, 1-dodecyl-3-methylimidazolium cation, 1-tetradecyl-3-methylimidazolium Cation, 1,2-dimethyl-3-propylimidazolium cation, 1-ethyl-2,3-dimethylimidazolium cation, 1-butyl-2,3-dimethylimidazolium cation, 1-hexyl-2,3-dimethyl Imidazolium such as imidazolium cation Thione; 1,3-dimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3-trimethyl-1,4,5,6-tetrahydropyrimidinium cation, 1,2,3 Tetrahydropyrimidinium cations such as 4-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation and 1,2,3,5-tetramethyl-1,4,5,6-tetrahydropyrimidinium cation 1,3-dimethyl-1,4-dihydropyrimidinium cation, 1,3-dimethyl-1,6-dihydropyrimidinium cation, 1,2,3-trimethyl-1,4-dihydropyrimidinium cation 1,2,3-trimethyl-1,6-dihydropyrimidinium cation, 1,2,3,4-tetramethyl-1,4-dihydropyrimidinium kathi Emissions, dihydropyrimidinium cation such as 1,2,3,4-tetramethyl-1,6-dihydropyrimidinium cation.

  Examples of the cation represented by the formula (C) include a pyrazolium cation and a pyrazolinium cation. Specific examples include 1-methylpyrazolium cation, 3-methylpyrazolium cation, 1-ethyl-2-methylpyrazolinium cation, and the like.

  As the cation represented by the formula (D), for example, a tetraalkylammonium cation, a trialkylsulfonium cation, a tetraalkylphosphonium cation, or a part of the alkyl group is substituted with an alkenyl group, an alkoxyl group, or an epoxy group. And the like. Specific examples include, for example, N, N-dimethyl-N-ethyl-N-propylammonium cation, N, N-dimethyl-N-ethyl-N-butylammonium cation, N, N-dimethyl-N-ethyl-N. -Pentylammonium cation, N, N-dimethyl-N-ethyl-N-hexylammonium cation, N, N-dimethyl-N-ethyl-N-heptylammonium cation, N, N-dimethyl-N-ethyl-N-nonyl Ammonium cation, N, N-dimethyl-N, N-dipropylammonium cation, N, N-dimethyl-N-propyl-N-butylammonium cation, N, N-dimethyl-N-propyl-N-pentylammonium cation, N, N-dimethyl-N-propyl-N-hexylammonium cation, N, N- Methyl-N-propyl-N-heptylammonium cation, N, N-dimethyl-N-butyl-N-hexylammonium cation, N, N-dimethyl-N-butyl-N-heptylammonium cation, N, N-dimethyl- N-pentyl-N-hexylammonium cation, N, N-dimethyl-N, N-dihexylammonium cation, trimethylheptylammonium cation, N, N-diethyl-N-methyl-N-propylammonium cation, N, N-diethyl -N-methyl-N-pentylammonium cation, N, N-diethyl-N-methyl-N-heptylammonium cation, N, N-diethyl-N-propyl-N-pentylammonium cation, triethylmethylammonium cation, triethylpropyl A Monium cation, triethylpentylammonium cation, triethylheptylammonium cation, N, N-dipropyl-N-methyl-N-ethylammonium cation, N, N-dipropyl-N-methyl-N-pentylammonium cation, N, N-dipropyl -N-butyl-N-hexylammonium cation, N, N-dipropyl-N, N-dihexylammonium cation, N, N-dibutyl-N-methyl-N-pentylammonium cation, N, N-dibutyl-N-methyl -N-hexylammonium cation, trioctylmethylammonium cation, N-methyl-N-ethyl-N-propyl-N-pentylammonium cation, tetramethylammonium cation, tetraethylammonium cation, teto Rabutylammonium cation, tetrahexylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium cation, glycidyltrimethylammonium cation, diallyldimethylammonium cation Tetraalkylammonium cations such as trimethylsulfonium cation, triethylsulfonium cation, tributylsulfonium cation, trihexylsulfonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldecylsulfonium cation, etc .; tetramethylphosphonium cation; Tetraethylphosphonium Examples thereof include tetraalkylphosphonium cations such as thione, tetrabutylphosphonium cation, tetrahexylphosphonium cation, phosphonium cation, triethylmethylphosphonium cation, tributylethylphosphonium cation, and trimethyldecylphosphonium cation.

  In the present invention, among the above cation components, cations represented by formula (A) (in particular, 1-ethylpyridinium cation, 1-butylpyridinium cation, 1-hexylpyridinium cation, 1-butyl-3-methylpyridinium) Cation, 1-butyl-4-methylpyridinium cation, 1-hexyl-3-methylpyridinium cation, pyridinium cation such as 1-butyl-3,4-dimethylpyridinium cation), a cation represented by formula (D) (particularly , Triethylmethylammonium cation, tributylethylammonium cation, trimethyldecylammonium cation, diethylmethylsulfonium cation, dibutylethylsulfonium cation, dimethyldecylsulfonium cation, triethylmethylphospho Cation, tributylethylphosphonium cation, trimethyldecylphosphonium cation, asymmetric tetraalkylammonium cation, trialkylsulfonium cation, tetraalkylphosphonium cation, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium cation , Diallyldimethylammonium cation, glycidyltrimethylammonium cation, etc.) are preferably used in that a particularly excellent antistatic ability can be obtained.

On the other hand, any anion component may be used as long as it can form an ionic liquid together with the cation component. For example, Cl ⁻ , Br ⁻ , I ⁻ , AlCl ₄ ⁻ , Al ₂ Cl ₇ ⁻ , BF ₄ ⁻ , PF ₆ ⁻ , ClO ₄ ⁻ , NO ₃ ⁻ , CH ₃ COO ⁻ , CF ₃ COO ⁻ , CH ₃ SO ₃ ⁻ , CF ₃ SO ₃ ⁻ , (CF ₃ SO ₂ ) ₂ N ⁻ , (CF ₃ SO ₂ ) ₃ C ⁻ , AsF ₆ ⁻ , SbF ₆ ⁻ , NbF ₆ ⁻ , TaF ₆ ⁻ , F (HF) _n ⁻ , (CN) ₂ N ⁻ , C ₄ F ₉ SO ₃ ⁻ , (C ₂ F ₅ SO ₂ ) ₂ N ⁻ , C ₃ F ₇ COO ⁻ , (CF ₃ SO ₂ ) (CF ₃ CO) N ^{− and the} like. Among these, an anionic component containing a fluorine atom is preferably used because an ionic compound having a low melting point is obtained.

The ionic liquid in the present invention is appropriately selected from the combination of the cation component and the anion component, and for example, 1-butylpyridinium tetrafluoroborate, 1-butylpyridinium hexafluorophosphate, 1-butyl-3-methylpyridinium tetra 1-butyl-3-methylpyridinium trifluoromethanesulfonate, 1-butyl-3-methylpyridinium bis (trifluoromethanesulfonyl) imide, 1-butyl-3-methylpyridinium bis (pentafluoroethanesulfonyl) imide, 1-butyl-3-methylpyridinium trifluoromethanesulfonate Hexylpyridinium tetrafluoroborate, 1,1-dimethylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpyrrolidinium bis (trifluoromethanes Phonyl) imide, 1-methyl-1-propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-pentylpyrrolidinium Bis (trifluoromethanesulfonyl) imide, 1-methyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1- Propylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-pentylpyrrolidinium bis (trifluoromethanesulfonyl) imi 1-ethyl-1-hexylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-heptylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropylpyrrolidinium bis (trifluoromethane Sulfonyl) imide, 1-propyl-1-butylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1,1-dibutylpyrrolidinium bis (trifluoromethanesulfonyl) imide, 1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-pentylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dimethylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-ethylpiperidinium bis (trifluoro Methanesulfonyl) imide, 1-methyl-1-propylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) ) Imide, 1-methyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-methyl-1-heptylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-propylpiperidinium bis (trifluoromethanesulfonyl) imide 1-ethyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-pentylpiperidinium bis (trifluoromethanesulfonyl) ) Imide, 1-ethyl-1-hexylpiperidinium bis (trifluoromethanesulfonyl) imide, 1-ethyl-1-heptylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dipropylpiperidinium bis (trifluoromethanesulfonyl) imide, -Propyl-1-butylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dibutylpiperidinium bis (trifluoromethanesulfonyl) imide, 1,1-dimethylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl- 1-ethylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1- Tylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-pentylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpyrrolidinium bis (pentafluoroethanesulfonyl) imide 1-methyl-1-heptylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-propylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-butylpyrrolidinium bis (Pentafluoroethanesulfonyl) imide, 1-ethyl-1-pentylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-hexylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl- 1- Heptylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dipropylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-propyl-1-butylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dibutylpyrrolidinium bis (pentafluoroethanesulfonyl) imide, 1-propylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dimethylpiperidinium bis (Pentafluoroethanesulfonyl) imide, 1-methyl-1-ethylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-propylpiperidinium bis (pentafluoro Tansulfonyl) imide, 1-methyl-1-butylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-methyl-1-hexylpiperidinium bis (penta Fluoroethanesulfonyl) imide, 1-methyl-1-heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-propylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-butylpiperidinium bis ( Pentafluoroethanesulfonyl) imide, 1-ethyl-1-pentylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-ethyl-1-hexylpiperidinium bis (pentafluoro) Ethanesulfonyl) imide, 1-ethyl-1-heptylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1,1-dipropylpiperidinium bis (pentafluoroethanesulfonyl) imide, 1-propyl-1-butylpiperidinium bis (pentafluoroethane) Sulfonyl) imide, 1,1-dibutylpiperidinium bis (pentafluoroethanesulfonyl) imide, 2-methyl-1-pyrroline tetrafluoroborate, 1-ethyl-2-phenylindole tetrafluoroborate, 1,2-dimethylindole tetrafluoro Borate, 1-ethylcarbazole tetrafluoroborate, 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3-methylimidazolium acetate, 1-ethyl Ru-3-methylimidazolium trifluoroacetate, 1-ethyl-3-methylimidazolium heptafluorobutyrate, 1-ethyl-3-methylimidazolium trifluoromethanesulfonate, 1-ethyl-3-methylimidazolium perfluorobutanesulfonate 1-ethyl-3-methylimidazolium dicyanamide, 1-ethyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-ethyl-3-methylimidazolium bis (pentafluoroethanesulfonyl) imide, 1- Ethyl-3-methylimidazolium tris (trifluoromethanesulfonyl) methide, 1-butyl-3-methylimidazolium tetrafluoroborate, 1-butyl-3-methylimidazolium hexafluorophosphate 1-butyl-3-methylimidazolium trifluoroacetate, 1-butyl-3-methylimidazolium heptafluorobutyrate, 1-butyl-3-methylimidazolium trifluoromethanesulfonate, 1-butyl-3-methylimidazolium perfluoro Butanesulfonate, 1-butyl-3-methylimidazolium bis (trifluoromethanesulfonyl) imide, 1-hexyl-3-methylimidazolium bromide, 1-hexyl-3-methylimidazolium chloride, 1-hexyl-3-methylimidazole 1-hexyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-3-methylimidazolium trifluoromethanesulfonate, 1-octyl-3-methylimidazole Rium tetrafluoroborate, 1-octyl-3-methylimidazolium hexafluorophosphate, 1-hexyl-2,3-dimethylimidazolium tetrafluoroborate, 1,2-dimethyl-3-propylimidazolium bis (trifluoromethanesulfonyl) Imido, 1-methylpyrazolium tetrafluoroborate, 3-methylpyrazolium tetrafluoroborate, N, N-dimethyl-N-ethyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl- N-ethyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl- N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-ethyl-N-nonylammonium bis ( Trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dipropylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-butylammonium bis (trifluoromethanesulfonyl) imide, N , N-dimethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-propyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl -N-propyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-butyl-N -Heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N-pentyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dimethyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) ) Imide, trimethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-propylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N Methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N-heptylammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-propyl-N-pentylammonium Bis (trifluoromethanesulfonyl) imide, triethylpropylammonium bis (trifluoromethanesulfonyl) imide, triethylpentylammonium bis (trifluoromethanesulfonyl) imide, triethylheptylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-methyl -N-ethylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N-methyl-N-pentylammonium bis (trifluoro) (Romethanesulfonyl) imide, N, N-dipropyl-N-butyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, N, N-dipropyl-N, N-dihexylammonium bis (trifluoromethanesulfonyl) imide, N, N -Dibutyl-
N-methyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, N, N-dibutyl-N-methyl-N-hexylammonium bis (trifluoromethanesulfonyl) imide, trioctylmethylammonium bis (trifluoromethanesulfonyl) imide, N-methyl-N-ethyl-N-propyl-N-pentylammonium bis (trifluoromethanesulfonyl) imide, 1-butylpyridinium (trifluoromethanesulfonyl) trifluoroacetamide, 1-butyl-3-methylpyridinium (trifluoromethanesulfonyl) Trifluoroacetamide, 1-ethyl-3-methylimidazolium (trifluoromethanesulfonyl) trifluoroacetamide, tetrahexylammonium bis (trifluoro) Methanesulfonyl) imide, diallyldimethylammonium tetrafluoroborate, diallyldimethylammonium trifluoromethanesulfonate, diallyldimethylammonium bis (trifluoromethanesulfonyl) imide, diallyldimethylammonium bis (pentafluoroethanesulfonyl) imide, N, N-diethyl-N— Methyl-N- (2-methoxyethyl) ammonium tetrafluoroborate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium trifluoromethanesulfonate, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (trifluoromethanesulfonyl) imide, N, N-diethyl-N-methyl-N- (2-methoxyethyl) ammonium bis (pe Tafluoroethanesulfonyl) imide, glycidyltrimethylammonium trifluoromethanesulfonate, glycidyltrimethylammonium bis (trifluoromethanesulfonyl) imide, glycidyltrimethylammonium bis (pentafluoroethanesulfonyl) imide, diallyldimethylbis (pentafluoroethanetansulfonyl) imide, etc. Can be mentioned.

  The method of synthesizing the ionic liquid is not particularly limited as long as the target ionic liquid can be obtained. In general, the document “Ionic liquids—the forefront and future of development” [published by CMC Publishing Co., Ltd.] The halide method, the hydroxide method, the acid ester method, the complex formation method, the neutralization method and the like as described in (1) are used. The synthesis method of the halide method, hydroxide method, acid ester method, complex formation method, and neutralization method will be described below using nitrogen-containing onium salts as examples, but other ions such as sulfur-containing onium salts and phosphorus-containing onium salts are also shown. The liquid can be obtained by the same method.

The halide method is carried out by reactions as shown in the following formulas (1) to (3).
First, a tertiary amine (R ₃ N) and a halogenated alkyl (RX: X represents a halogen atom, for example, chlorine, bromine or iodine is used) are reacted to obtain a halide (R ₄ NX) (formula (1)).
The obtained halide is formed into a salt with the target anion, such as an acid (HA) or salt having the anion structure (A ⁻ ) of the target ionic liquid (MA: M is ammonium, lithium, sodium, potassium, etc.) The target ionic liquid (R ₄ NA) is obtained by reacting with (cation) (formulas (2) and (3)).
R ₃ N + RX → R ₄ NX (X: Cl, Br, I) (1)
R ₄ NX + HA → R ₄ NA + HX (2)
R ₄ NX + MA → R ₄ NA + MX (M: NH ₄ , Li, Na, K, Ag, etc.) (3)

The hydroxide method is carried out by reactions as shown in the following formulas (4) to (8).
First, halide (R ₄ NX) is subjected to ion exchange membrane electrolysis (formula (4)), OH type ion exchange resin method (formula (5)) or reaction with silver oxide (Ag ₂ O) (reaction formula (6 )) To obtain hydroxide (R ₄ NOH).
The obtained hydroxide is used in the reactions of the reaction formulas (7) and (8) in the same manner as in the halogenation method to obtain the target ionic liquid (R ₄ NA).
R ₄ NX + H ₂ O → R ₄ NOH + ½H ₂ + ½X ₂ (X: Cl, Br, I) (4)
R ₄ NX + P—OH → R ₄ NOH + PX (P—OH: OH type ion exchange resin) (5)
_{R 4 NX + 1 / 2Ag 2} O + 1 / 2H 2 O → R 4 NOH + AgX (6)
R ₄ NOH + HA → R ₄ NA + H ₂ O (7)
R ₄ NOH + MA → R ₄ NA + MOH (M: NH ₄ , Li, Na, K, Ag, etc.) (8)

The acid ester method is performed by a reaction as shown in the following formulas (9) to (11).
First, a tertiary amine (R ₃ N) is reacted with an acid ester (ROY) to obtain an acid ester (R ₄ NOY) (formula (9)). Examples of the acid ester include esters of inorganic acids such as sulfuric acid, sulfurous acid, phosphoric acid, phosphorous acid, and carbonic acid, and esters of organic acids such as methanesulfonic acid, methylphosphonic acid, and formic acid.
The obtained acid ester (R ₄ NOY) is used in the reactions of the reaction formulas (10) and (11) in the same manner as in the halogenation method to obtain the target ionic liquid (R ₄ NA). Further, by using methyl trifluoromethanesulfonate, methyl trifluoroacetate or the like as the acid ester, an ionic liquid can be directly obtained.
R ₃ N + ROY → R ₄ NOY (9)
R ₄ NOY + HA → R ₄ NA + HOY (when OY: O (C═O) OR, R ₄ NO (C═O) OR + HA → R ₄ NA + CO ₂ + ROH) (10)
R ₄ NOY + MA → R ₄ NA + MOY (M: NH ₄ , Li, Na, K, Ag, etc.) (11)

The complex formation method is performed by a reaction as shown in the following formulas (12) to (15).
First, quaternary ammonium halide (R ₄ NX), quaternary ammonium hydroxide (R ₄ NOH), quaternary ammonium carbonate ester (R ₄ NOCO ₂ CH ₃ ), etc. are converted to hydrogen fluoride (HF). And a reaction with ammonium fluoride (NH ₄ F) to obtain a quaternary ammonium fluoride salt (formulas (12) to (14)).
An ionic liquid can be obtained by complexing the obtained quaternary ammonium fluoride with a fluoride such as BF ₃ , AlF ₃ , PF ₅ , ASF ₅ , SbF ₅ , NbF ₅ , TaF ₅ (formula ( 15)).
R ₄ NX + HF → R ₄ NF + HX (X: Cl, Br, I) (12)
R ₄ NY + HF → R ₄ NF + HY (Y: OH, OCO ₂ CH ₃ ) (13)
R ₄ NY + NH ₄ F → R ₄ NF + NH ₃ + HY (Y: OH, OCO ₂ CH ₃ ) (14)
R ₄ NF + MF _n-1 → R ₄ NMF _n (MF _n-1 : BF ₃ , AlF ₃ , PF ₅ , ASF ₅ , SbF ₅ , NbF ₅ , TaF ₅ etc.) (15)

The neutralization method is performed by a reaction as shown in the following formula (16).
Tertiary amine and HBF ₄ , HPF ₆ , CH ₃ COOH, CF ₃ COOH, CF ₃ SO ₃ H, (CF ₃ SO ₂ ) ₂ NH, (CF ₃ SO ₂ ) ₃ CH, (C ₂ F ₅ SO ₂ ) ₂ It can be obtained by reacting with an organic acid such as NH.
R ₃ N + HZ → R ₃ HN + Z− [HZ: HBF ₄ , HPF ₆ , CH ₃ COOH, CF ₃ COOH, CF ₃ SO ₃ H, (CF ₃ SO ₂ ) ₂ NH, (CF ₃ SO ₂ ) ₃ CH, ( Organic acids such as C ₂ F ₅ SO ₂ ) ₂ NH] (16)

  R in the above formulas (1) to (16) represents a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and may contain a hetero atom.

  The blending amount of the ionic liquid can be appropriately adjusted depending on the compatibility between the polymer to be used and the ionic liquid. For example, 0.01 to 40 parts by weight is preferable with respect to 100 parts by weight of the polymer, and 0.05 to 20 Part by weight is more preferable, 0.1 to 10 parts by weight is further preferable, and 0.2 to 4 parts by weight is most preferable. If the blending amount of the ionic liquid is less than 0.01 parts by weight, sufficient antistatic properties tend to be difficult to obtain. On the other hand, if the blending amount of the ionic liquid exceeds 40 parts by weight, the adherend is contaminated. There is a tendency to increase.

(Base polymer)
In the present invention, a polymer having a glass transition temperature (Tg) of 0 ° C. or lower is used as the base polymer, and among them, the glass transition temperature (Tg) is preferably −100 ° C. to −5 ° C., particularly −80 ° C. to −10. ° C is preferred. When the glass transition temperature (Tg) exceeds 0 ° C., it is difficult to obtain sufficient adhesive force even when an ionic liquid is contained.

  As a polymer having a glass transition temperature (Tg) of 0 ° C. or lower, one or two acrylates and / or methacrylates (hereinafter sometimes referred to as (meth) acrylates) having an alkyl group having 1 to 14 carbon atoms. Acrylic polymer, natural rubber, styrene-isoprene-styrene block copolymer (SIS block copolymer), styrene-butadiene-styrene block copolymer (SBS block copolymer), styrene-ethylene -Polymers generally used as pressure-sensitive adhesive polymers such as butylene-styrene block copolymer (SEBS block copolymer), styrene-butadiene rubber, polybutadiene, polyisoprene, polyisobutylene, butyl rubber, chloroprene rubber, silicone rubber, etc. Is mentioned.

  Among these, since the balance of compatibility with the ionic liquid and excellent adhesive properties are obtained, the main component is one or more of (meth) acrylates having an alkyl group having 1 to 14 carbon atoms. Acrylic polymers are preferred, and the weight-average molecular weight is mainly composed of a monomer containing 50 to 100% by weight of one or more (meth) acrylates having an alkyl group having 1 to 14 carbon atoms. Is preferably an acrylic polymer having 100,000 or more.

  Examples of the (meth) acrylate having an alkyl group having 1 to 14 carbon atoms include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl ( (Meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl ( Examples include meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, and n-tetradecyl (meth) acrylate.

  When the pressure-sensitive adhesive sheet of the present invention is used for a surface protective film, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl are used as the acrylic polymer. (Meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, etc. An acrylic polymer made of (meth) acrylate having an alkyl group having 6 to 14 carbon atoms is preferably used. By using an acrylic polymer composed of (meth) acrylate having an alkyl group having 6 to 14 carbon atoms, it becomes easy to control the adhesive force to the adherend to be low, and has excellent removability. It becomes.

  As other components, a sulfonic acid group-containing monomer and a phosphoric acid group-containing monomer are suitably used within the range where the glass transition temperature (Tg) is 0 ° C. or lower (usually −100 ° C. or higher) because the adhesive performance is easily balanced. , Cyano group-containing monomers, vinyl esters, aromatic vinyl compounds and other cohesive strength / heat resistance improving components, carboxyl group-containing monomers, acid anhydride group-containing monomers, hydroxyl group-containing monomers, amide group-containing monomers, amino group-containing Monomer, epoxy group-containing monomer, N-acryloylmorpholine, vinyl ethers, 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate, butoxyethyl (meth) acrylate, etc. A component having a functional group can be used. Other components can be used alone or in combination of two or more.

  However, when a (meth) acrylate having an acid functional group such as a carboxyl group, a sulfonic acid group, or a phosphoric acid group is used, the acid value of the acrylic polymer is 39 or less (particularly, the acid value is less than 30). It is more preferable to adjust to. When the acid value of the acrylic polymer exceeds 39, the antistatic property tends to deteriorate.

  The acid value can be adjusted by the blending amount of the (meth) acrylate having an acid functional group, for example, an acrylic polymer obtained by copolymerizing 2-ethylhexyl acrylate and acrylic acid as an acrylic polymer having a carboxyl group. However, in this case, the acid value can be satisfied by adjusting acrylic acid to 5.0 parts by weight or less with respect to 100 parts by weight of the total amount of 2-ethylhexyl acrylate and acrylic acid. Moreover, when using for a surface protection film, it is preferable to adjust so that the acid value of an acrylic polymer may be 1 or less. By setting the acid value of the acrylic polymer to 1 or less, a surface protective film excellent in easy peelability from the adherend can be obtained.

  Examples of the sulfonic acid group-containing monomer include styrene sulfonic acid, allyl sulfonic acid, 2- (meth) acrylamide-2-methylpropane sulfonic acid, (meth) acrylamide propane sulfonic acid, sulfopropyl (meth) acrylate, and (meth) acryloyloxy. And naphthalenesulfonic acid.

  Examples of the phosphoric acid group-containing monomer include 2-hydroxyethylacryloyl phosphate. Examples of the cyano group-containing monomer include acrylonitrile. Examples of vinyl esters include vinyl acetate. Styrene is mentioned as an aromatic vinyl compound. Examples of the carboxyl group-containing monomer include (meth) acrylic acid, carboxyethyl (meth) acrylate, carboxypentyl (meth) acrylate, itaconic acid, maleic acid, fumaric acid, and crotonic acid. Examples of the acid anhydride group-containing monomer include maleic anhydride and itaconic anhydride.

  As hydroxyl group-containing monomers, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, 6-hydroxyhexyl (meth) acrylate, 8-hydroxyoctyl (meth) acrylate 10-hydroxydecyl (meth) acrylate, 12-hydroxylauryl (meth) acrylate, (4-hydroxymethylcyclohexyl) methyl acrylate, N-methylol (meth) acrylamide, N-methylol (meth) acrylamide, vinyl alcohol, allyl alcohol , 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, and the like.

  Examples of the amide group-containing monomer include (meth) acrylamide, dimethyl (meth) acrylamide, diethyl (meth) acrylamide, and isopropyl (meth) acrylamide.

  Examples of the amino group-containing monomer include N, N-dimethylaminoethyl (meth) acrylate and N, N-dimethylaminopropyl (meth) acrylate. Examples of the epoxy group-containing monomer include glycidyl (meth) acrylate and allyl glycidyl ether.

  Examples of vinyl ethers include vinyl ethyl ether.

  As the acrylic polymer of the present invention, an ether group-containing monomer component such as an alkylene glycol-containing acrylate or an alkylene oxide group-containing reactive surfactant can be used as a copolymerization component in order to develop further excellent low contamination. . The details of the reason why such characteristics are manifested by copolymerizing the ether group-containing monomer component are not clear, but the ionic liquid is less likely to bleed due to the coordination of the ionic liquid to the ether group, and has excellent antistatic properties. It is presumed that low pollution is achieved at the same time.

  The alkylene glycol-containing acrylate is preferably an acrylate having an alkylene group having 1 to 6 carbon atoms, more preferably 2 to 4 carbon atoms as an oxyalkylene unit. Specific examples of the alkylene group include an oxymethylene group, an oxyethylene group, an oxypropylene group, and an oxybutylene group. The number of moles of oxyalkylene units added to the (meth) acrylate is preferably about 1 to 50, more preferably 2 to 30 from the viewpoint of coordination of the ionic liquid. The terminal of the oxyalkylene chain may be a hydroxyl group or may be substituted with an alkyl group, a phenyl group or the like.

  Specific examples of alkylene glycol group-containing (meth) acrylates include methoxy-polyethylene glycol (meth) acrylate types such as methoxy-diethylene glycol (meth) acrylate and methoxy-triethylene glycol (meth) acrylate; ethoxy-diethylene glycol (meth) acrylate Ethoxy-polyethylene glycol (meth) acrylate type such as ethoxy-triethylene glycol (meth) acrylate; butoxy-polyethylene glycol (meth) acrylate type such as butoxy-diethylene glycol (meth) acrylate and butoxy-triethylene glycol (meth) acrylate Phenoxy-diethylene glycol (meth) acrylate, phenoxy-triethylene glycol (meth) acrylate, etc. Phenoxy - polyethylene glycol (meth) acrylate type; methoxy - methoxy and dipropylene glycol (meth) acrylate - polypropylene glycol (meth) acrylate type, and the like.

  The alkylene glycol group-containing (meth) acrylate may be used alone or in combination of two or more, but in the monomer component of the (meth) acrylic polymer, less than 50% by weight It is preferable that it is 0.05 to 30 weight%. When the alkylene glycol group-containing (meth) acrylate is contained in the above range, it is possible to exhibit excellent antistatic effects as well as low contamination.

  The alkylene oxide group-containing reactive surfactant refers to an alkylene oxide group-containing compound having a reactive unsaturated bond. Specific examples include an anionic reactive surfactant, a nonionic reactive surfactant, and a cationic reactive surfactant having an acryloyl group, a methacryloyl group, or an allyl group. Among these, an anionic reactive surfactant, a nonionic reactive surfactant, a cationic reactive surfactant and the like having an acryloyl group having a ethylene oxide group, a methacryloyl group or an allyl group are preferably used.

Examples of the anionic reactive surfactant include those represented by the following formulas (A1) to (A13).
[In the formula (A1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, M represents an alkali metal, alkaline earth metal, or ammonium group, Represents a hydroxyalkylammonium group having 1 to 4 carbon atoms, R ³ and R ⁴ are the same or different and represent an alkylene group having 1 to 6 carbon atoms, n represents 0 to 50, and m represents a number of 0 to 20 ]
[In the formula (A2), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, and R ³ and R ⁴ are the same or different, And M ¹ and M ² are the same or different and each represents an alkali metal, an alkaline earth metal, or ammonium, a hydroxyalkylammonium group having 1 to 4 carbon atoms, and n is 0 to 50, m Represents a number from 0 to 20]
[In the formula (A3), R ¹ represents a hydrogen atom or a methyl group, R ² and R ⁷ are the same or different, represent an alkylene group having 1 to 6 carbon atoms, and R ³ and R ⁵ are the same or different. Represents a hydrogen atom or an alkyl group, R ⁴ and R ⁶ are the same or different and each represents a hydrogen atom, an alkyl group, a benzyl group or a styrene group, M represents an alkali metal, an alkaline earth metal or an ammonium group, n and m represents a number from 1 to 50]
[In Formula (A4), R ¹ represents a hydrogen atom or a methyl group, R ² represents an alkylene group having 1 to 6 carbon atoms, M represents an alkali metal, alkaline earth metal, or ammonium group, and n represents 2 Represents a number of ~ 50. ]
[In Formula (A5), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, and R ³ and R ⁴ are the same or different, and To M represents an alkylene group, M represents an alkali metal, an alkaline earth metal, or an ammonium group or a hydroxyalkylammonium group having 1 to 4 carbon atoms, n represents 0 to 50, and m represents a number of 0 to 20. ]
[In Formula (A6), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, and R ³ and R ⁴ are the same or different, and And M ¹ and M ² are the same or different and each represents an alkali metal, an alkaline earth metal, ammonium or a hydroxyalkylammonium group having 1 to 4 carbon atoms, n is 0 to 50, m is Represents a number from 0 to 20]
[In Formula (A7), R ¹ represents a hydrocarbon group, an amino group or a carboxylic acid residue, R ² represents an alkylene group having 1 to 6 carbon atoms, and n represents a number of 0 to 50]
[In Formula (A8), R ¹ represents a hydrocarbon group having 1 to 30 carbon atoms, R ² represents a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms, R ³ represents a hydrogen atom or a propenyl group, R ⁴ represents an alkylene group having 1 to 6 carbon atoms, M represents an alkali metal, alkaline earth metal, ammonium group or alkanolamine residue, and n represents a number of 1 to 50]
[In Formula (A9), R ¹ represents a hydrogen atom or a methyl group, R ² and R ⁴ are the same or different and represent an alkylene group having 1 to 6 carbon atoms, and R ³ represents a carbon atom having 1 to 30 carbon atoms. Represents a hydrogen group, M represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group or an alkanol ammonium group, and n and m represent a number of 1 to 50]
Wherein (A10), R ¹ and R ⁵ are the same or different, represent a hydrogen atom or a methyl group, R ² and R ⁴ are the same or different and each represents an alkylene group having a carbon number of 1 to 6, R ³ Represents a hydrocarbon group having 1 to 30 carbon atoms, M represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group or an alkanol ammonium group, and n and m represent an integer of 1 to 50]
[In Formula (A11), R ¹ represents an alkylene group having 1 to 6 carbon atoms, R ² represents a hydrocarbon group having 1 to 30 carbon atoms, M represents a hydrogen atom, an alkali metal, an alkaline earth metal, or ammonium. A group or an amine group, and n represents an integer of 1 to 50]
Wherein ^{(A12), R 1, R} 2 and R ³ are the same or different, represent a hydrogen atom or a methyl group, R ⁴ is is R ⁴ in the case of an alkylene group (0 carbon atoms having 0 to 30 carbon atoms R ⁵ and R ⁶ are the same or different and each represents an alkylene group having 1 to 30 carbon atoms. m represents a number from 0 to 50, n represents a number from 0 to 100, and (m + n) represents a number from 1 to 150. M represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group or an alkanol ammonium group]
[In Formula (A13), R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom or a methyl group; R ⁴ represents an alkylene group having 0 to 30 carbon atoms (in the case of 0 carbon atoms, R ⁴ is R ⁵ and R ⁶ are the same or different and each represents an alkylene group having 1 to 30 carbon atoms. m represents a number from 0 to 50, n represents a number from 0 to 100, and (m + n) represents a number from 1 to 150. M ¹ and M ² are the same or different and each represents a hydrogen atom, an alkali metal, an alkaline earth metal, an ammonium group or an alkanol ammonium group]

Examples of the nonionic reactive surfactant include those represented by formulas (N1) to (N6).
[In the formula (N1), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, and R ³ and R ⁴ are the same or different, To 6 represents an alkylene group, and n and m represent a number of 0 to 50]
[In the formula (N2), R ¹ represents a hydrogen atom or a methyl group, R ² represents a hydrocarbon group or an acyl group having 1 to 30 carbon atoms, and R ³ and R ⁴ are the same or different, To 6 represents an alkylene group, and n and m represent a number of 0 to 50]
[In Formula (N3), R ¹ represents a hydrogen atom or a methyl group, R ² and R ³ are the same or different and represent an alkylene group having 1 to 6 carbon atoms, and R ⁴ represents a carbon atom having 1 to 30 carbon atoms. Represents a hydrogen group or an acyl group, and n and m represent a number of 0 to 50]
[In the formula (N4), R ¹ and R ² are the same or different and represent a hydrocarbon group having 1 to 30 carbon atoms, R ³ represents a hydrogen atom or a propenyl group, and R ⁴ has 1 to 6 carbon atoms. Represents an alkylene group, and n represents a number of 1 to 50]
[In formula (N5), R ¹ , R ² and R ³ are the same or different and each represents a hydrogen atom or a methyl group; R ⁴ represents an alkylene group having 0 to 30 carbon atoms (in the case of 0 carbon atoms, R ⁴ is R ⁵ and R ⁶ are the same or different and each represents an alkylene group having 1 to 30 carbon atoms. m represents a number from 0 to 50, n represents a number from 0 to 100, and (m + n) represents a number from 1 to 150]
[In formula (N6), R ¹ and R ³ are the same or different and each represents an alkylene group having 1 to 6 carbon atoms; R ² and R ⁴ are the same or different and represent a hydrogen atom or a hydrocarbon group having 1 to 30 carbon atoms; Or an acyl group, and n and m are 0 to 50, and (n + m) represents a number from 3 to 50]

Examples of the cationic reactive surfactant include those represented by the formulas (C1) and (C2).
[In Formula (C1), R ¹ and R ² are the same or different and each represents an alkyl group having 1 to 30 carbon atoms, R ³ represents a hydrocarbon group having 1 to 30 carbon atoms, and X represents chlorine or bromine. ]
[In the formula (C2), R represents a hydrocarbon group having 1 to 30 carbon atoms and may contain a hetero atom]

  The reactive surfactants may be used alone or in combination of two or more. As the usage-amount of a reactive surfactant, it is preferable that it is 20 weight% or less in the monomer component of a (meth) acrylic-type polymer, 0.05-10 weight% is more preferable, 0.1-5 weight % Is particularly preferred. The ionic liquid containing the reactive surfactant in the above range can exhibit an excellent bleed suppressing effect and a contamination reducing effect on the adherend.

  The acrylic polymer can be obtained by a polymerization method generally used as a synthesis method of an acrylic polymer such as solution polymerization, emulsion polymerization, bulk polymerization, suspension polymerization.

  In the present invention, a pressure-sensitive adhesive sheet having further excellent heat resistance can be obtained by appropriately crosslinking a base polymer (particularly acrylic polymer). As specific means of the crosslinking method, a general crosslinking agent such as an isocyanate compound, an epoxy compound, a melamine resin, an aziridine derivative or the like is added, and a carboxyl group, a hydroxyl group, which is a crosslinking group point in the base polymer, There is a method of reacting with an amino group, an amide group or the like.

  Examples of the isocyanate compound include aromatic isocyanates such as tolylene diisocyanate and xylene diisocyanate; alicyclic isocyanates such as isophorone diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate. These compounds may be used alone or in combination of two or more.

  Examples of the polyisocyanate compound include lower aliphatic polyisocyanates such as butylene diisocyanate and hexamethylene diisocyanate; cyclopentylene diisocyanate, cyclohexylene diisocyanate, and isophorone diester. Alicyclic isocyanates such as isocyanates; aromatic diisocyanates such as 2,4-tolylene diisocyanate, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate Trimethylolpropane / tolylene diisocyanate trimer adduct (trade name “Colone L” manufactured by Nippon Polyurethane Industry Co., Ltd.), Trimethylolpropane / hexamethylene diisocyanate trimer Additives (trade name “Colonate HL”, manufactured by Nippon Polyurethane Industry Co., Ltd.), hexamethylene diisocyanate Cyanurate body (trade name "Coronate - door HX", manufactured by Nippon Polyurethane Industry Co., Ltd.) such as isocyanate - door adducts, and the like. These compounds may be used alone or in combination of two or more.

  Examples of the epoxy compound include N, N, N ′, N′-tetraglycidyl-m-xylenediamine (trade name “TETRAD-X”, manufactured by Mitsubishi Gas Chemical Co., Ltd.), 1,3-bis (N, N-di). And glycidylaminomethyl) cyclohexane (trade name “TETRAD-C”, manufactured by Mitsubishi Gas Chemical Co., Ltd.). These compounds may be used alone or in combination of two or more.

  Examples of the melamine resin include hexamethylol melamine. Examples of the aziridine derivatives include commercial products such as trade name “HDU” (manufactured by Mutual Yakuhin Co., Ltd.), trade name “TAZM” (manufactured by Mutual Yakuko Co., Ltd.), and trade name “TAZO” (manufactured by Mutual Yakuko). Can be mentioned. These compounds may be used alone or in combination of two or more.

  Among these crosslinking agents, isocyanate compounds and epoxy compounds are preferably used from the viewpoint of obtaining an appropriate cohesive force. These compounds may be used alone or in combination of two or more.

  The amount of the crosslinking agent used is appropriately adjusted depending on the balance with the acrylic polymer to be crosslinked, and further depending on the application of the pressure-sensitive adhesive sheet. In order to obtain sufficient heat resistance due to the cohesive strength of the acrylic pressure-sensitive adhesive, it is preferably contained in an amount of 0.01 to 15 parts by weight with respect to 100 parts by weight of the acrylic polymer, and 0.5 to 10 parts by weight. It is more preferably contained, more preferably 0.5 to 5 parts by weight, and most preferably 1 to 3 parts by weight. When the content is less than 0.01 parts by weight, the crosslinking formation by the crosslinking agent becomes insufficient, the cohesive force of the pressure-sensitive adhesive composition becomes small, and sufficient heat resistance may not be obtained. There is a tendency to cause. On the other hand, if the content exceeds 15 parts by weight, the cohesive force of the polymer becomes too large, the fluidity is lowered, the wettability to the adherend is insufficient, and it tends to cause peeling.

  Further, a polyfunctional monomer having two or more active energy ray-reactive unsaturated bonds may be added as a substantial cross-linking agent, and cross-linking may be performed with active energy rays or the like.

  As the polyfunctional monomer having two or more active energy ray-reactive unsaturated bonds, one or two that can form a crosslinked structure by irradiation with active energy rays such as vinyl group, acryloyl group, methacryloyl group, vinylbenzyl group, etc. A polyfunctional monomer component having two or more active energy ray reactive groups of at least species is used. In general, those having 10 or less active energy ray-reactive unsaturated bonds are preferably used. Two or more polyfunctional monomers can be used in combination. Specific examples of the polyfunctional monomer include ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, 1,6 hexanediol di (meth) ) Acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, divinylbenzene, N, N′-methylenebisacrylamide and the like.

  The amount of the polyfunctional monomer used is appropriately adjusted depending on the balance with the acrylic polymer to be crosslinked and further depending on the application of the pressure-sensitive adhesive sheet. In order to obtain sufficient heat resistance due to the cohesive force of the acrylic pressure-sensitive adhesive, it is preferable to blend 0.1 to 30 parts by weight with respect to 100 parts by weight of the acrylic polymer. Further, in terms of flexibility and adhesiveness, 10 parts by weight or less (for example, 0.1 to 10 parts by weight), preferably 5 parts by weight or less (for example, 0.1 to 5 parts by weight) with respect to 100 parts by weight of the acrylic polymer. Part), and more preferably 3 parts by weight or less (for example, 0.1 to 3 parts by weight).

  Examples of active energy rays include ultraviolet rays, laser rays, α rays, β rays, γ rays, x rays, electron rays, etc., but ultraviolet rays (preferably from the viewpoint of good controllability and handleability, and cost. UV light having a wavelength of 200 to 400 nm). Ultraviolet rays can be irradiated using an appropriate light source such as a high-pressure mercury lamp, a microwave excitation lamp, or a chemical lamp. Moreover, when using an ultraviolet-ray as an active energy ray, it is preferable to add a photoinitiator to an acrylic adhesive.

  The photopolymerization initiator may be any substance that generates radicals or cations by irradiating ultraviolet rays having an appropriate wavelength that can trigger the polymerization reaction according to the type of the active energy ray reactive component.

  Examples of radical photopolymerization initiators include benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, o-benzoylbenzoic acid methyl-p-benzoin ethyl ether, benzoin isopropyl ether, and α-methylbenzoin; benzyldimethyl ketal and trichloroacetophenone Acetophenones such as 2,2-diethoxyacetophenone and 1-hydroxycyclohexyl phenyl ketone; propio such as 2-hydroxy-2-methylpropiophenone and 2-hydroxy-4'-isopropyl-2-methylpropiophenone Phenones; benzophenones such as benzophenone, methylbenzophenone, p-chlorobenzophenone, p-dimethylaminobenzophenone; 2-chlorothioxanthone, 2-ethylthio Thioxanthones such as Sandton and 2-isopropylthioxanthone; bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, (2,4,6-trimethylbenzoyl)- Acylphosphine oxides such as (ethoxy) -phenylphosphine oxide; benzyl, dibenzosuberone, α-acyloxime ester and the like.

  Examples of photocationic polymerization initiators include onium salts such as aromatic diazonium salts, aromatic iodonium salts, and aromatic sulfonium salts; organometallic complexes such as iron-allene complexes, titanocene complexes, and arylsilanol-aluminum complexes; nitrobenzyl esters , Sulfonic acid derivatives, phosphoric acid esters, sulfonic acid derivatives, phosphoric acid esters, phenol sulfonic acid esters, diazonaphthoquinone, N-hydroxyimide sulfonate and the like.

  A photoinitiator may be used independently and may use 2 or more types together. The amount of the photopolymerization initiator used is, for example, usually about 0.1 to 10 parts by weight, preferably about 0.2 to 7 parts by weight with respect to 100 parts by weight of the acrylic polymer.

  Furthermore, it is possible to use a photopolymerization initiator initiation assistant such as amines in combination. Examples of the initiation assistant include 2-dimethylaminoethyl benzoate, dimethylaminoacetophenone, p-dimethylaminobenzoic acid ethyl ester, p-dimethylaminobenzoic acid isoamyl ester, and the like. These may be used alone or in combination of two or more. The amount of the starting aid used is, for example, about 0.05 to 10 parts by weight, preferably about 0.1 to 7 parts by weight with respect to 100 parts by weight of the acrylic polymer.

  Further, the pressure-sensitive adhesive composition of the present invention includes various conventionally known tackifiers, surface lubricants, leveling agents, antioxidants, corrosion inhibitors, light stabilizers, ultraviolet absorbers, polymerization inhibitors, silanes, and the like. Additives such as coupling agents, inorganic or organic fillers, powders such as metal powders and pigments, particles, and foils can be added as appropriate according to the intended use.

  Furthermore, an ether group-containing compound can be appropriately added to the pressure-sensitive adhesive composition of the present invention. By adding an ether group-containing compound to the pressure-sensitive adhesive composition, the reason is not clear, but the antistatic property can be further improved. Further, by adding an ether group-containing compound, wettability is improved with respect to a nonpolar material such as fluorine, and the transfer of the ionic liquid to the adherend can be performed efficiently.

  The ether group-containing compound is not particularly limited as long as it is a compound having an ether group, and a well-known and commonly used ether group-containing compound is used. Examples of the ether group-containing compound include polyether polyol compounds and alkylene oxide group-containing compounds. Among these, a polyether polyol compound, an alkylene glycol group-containing (meth) acrylate polymer, and an ether type surfactant are preferably used because they are easy to balance the compatibility with the base polymer.

  Examples of the polyether polyol compound include polyethylene glycol, polypropylene glycol (diol type), polypropylene glycol (triol type), polytetramethylene ether glycol, and the above derivatives and polypropylene glycol-polyethylene glycol-polypropylene glycol block copolymers, polypropylene glycol. -A block copolymer of polyethylene glycol, a block copolymer of polyethylene glycol-polypropylene glycol-polyethylene glycol, a random copolymer of polyethylene glycol and polypropylene glycol, a block copolymer, and the like. The end of the glycol chain may be a hydroxyl group, or may be substituted with an alkyl group, a phenyl group or the like.

  As the alkylene glycol group-containing (meth) acrylate polymer, an acrylic polymer having an alkylene glycol group-containing (meth) acrylate as an essential component is used. Examples of the oxyalkylene unit of (meth) acrylate include those having an alkylene group having 1 to 6 carbon atoms, such as an oxymethylene group, an oxyethylene group, an oxypropylene group, and an oxybutylene group. The number of moles of oxyalkylene units added to the (meth) acrylate is preferably about 1 to 50, and more preferably about 2 to 30 from the viewpoint of coordination of the ionic liquid. The terminal of the oxyalkylene chain may be a hydroxyl group or may be substituted with an alkyl group or a phenyl group.

  Specific examples of the alkylene glycol group-containing (meth) acrylate include, for example, methoxy-polyethylene glycol (meth) acrylate types such as methoxy-diethylene glycol (meth) acrylate and methoxy-triethylene glycol (meth) acrylate; ethoxy-diethylene glycol (meta ) Ethoxy-polyethylene glycol (meth) acrylate type such as acrylate, ethoxy-triethylene glycol (meth) acrylate; Butoxy-polyethylene glycol (meth) such as butoxy-diethylene glycol (meth) acrylate, butoxy-triethylene glycol (meth) acrylate Acrylate type; phenoxy-diethylene glycol (meth) acrylate, phenoxy-triethylene glycol (meth) acrylic Phenoxy over bets like - polyethylene glycol (meth) acrylate type; methoxy - methoxy and dipropylene glycol (meth) acrylate - polypropylene glycol (meth) acrylate type, and the like.

  In addition to the above components, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, t-butyl (meth) acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl ( (Meth) acrylate, n-octyl (meth) acrylate, isooctyl (meth) acrylate, n-nonyl (meth) acrylate, isononyl (meth) acrylate, n-decyl (meth) acrylate, isodecyl (meth) acrylate, n-dodecyl ( A (meth) acrylate having a C 1-14 alkyl group such as (meth) acrylate, n-tridecyl (meth) acrylate, n-tetradecyl (meth) acrylate, or the like may be used as a copolymerization component.

  Furthermore, phosphate group-containing (meth) acrylate, cyano group-containing (meth) acrylate, vinyl esters, aromatic vinyl compounds, acid anhydride group-containing (meth) acrylate, hydroxyl group-containing (meth) acrylate, amide group-containing (Meth) acrylate, amino group-containing (meth) acrylate, epoxy group-containing (meth) acrylate, N-acryloylmorpholine, and vinyl ethers may be used as a copolymerization component.

  The proportion of the alkylene glycol group-containing (meth) acrylate contained in the alkylene glycol group-containing (meth) acrylate polymer is preferably 10 to 70% by weight. When the proportion of the alkylene glycol group-containing (meth) acrylate is less than 10% by weight, the compatibility with the ionic liquid is deteriorated and sufficient charging characteristics tend to be hardly obtained. On the other hand, when the ratio of the alkylene glycol group-containing (meth) acrylate exceeds 70% by weight, the compatibility with the acrylic polymer as the base polymer is lowered, and it tends to be difficult to obtain sufficient charging characteristics. An alkylene glycol group containing (meth) acrylate may be used independently and may be used in combination of 2 or more type.

  Ether type surfactants include polyoxyalkylene fatty acid esters, polyoxyalkylene sorbitan fatty acid esters, polyoxyalkylene sorbitol fatty acid esters, polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl allyl ethers, polyoxyalkylene alkyl Nonionic surfactants such as phenyl ethers, polyoxyalkylene derivatives, polyoxyalkylene alkylamines, polyoxyalkylene alkylamine fatty acid esters; polyoxyalkylene alkyl ether sulfates, polyoxyalkylene alkyl ether phosphates Salts, polyoxyalkylene alkylphenyl ether sulfates, polyoxyalkylene alkylphenyl ether phosphates Anionic surfactants such as ether salts; cationic surfactants having an alkylene oxide group; zwitterionic surfactants. Further, the ether type surfactant may have a reactive substituent such as a (meth) acryloyl group or an allyl group in the molecule.

  Among these, polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol fatty acid esters, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyl ethers, polyoxyethylene alkyl phenyl ethers , Polyoxyethylene derivatives, polyoxyethylene alkylamines, polyoxyethylene alkylamine fatty acid esters and other nonionic surfactants having an ethylene oxide group; polyoxyethylene alkyl ether sulfate salts, polyoxyethylene alkyl ether phosphoric acid Ester salt, polyoxyethylene alkylphenyl ether sulfate ester salt, polyoxyethylene alkylphenyl ether phosphate ester salt, etc. Anionic surfactants having an ethylene oxide group; cationic surfactants and zwitterionic surfactants having an ethylene oxide group is preferably used. Moreover, you may have reactive substituents, such as a (meth) acryloyl group and an allyl group, in a molecule | numerator.

  The added mole number of the oxyalkylene unit of the surfactant having an alkylene oxide group is preferably about 1 to 50, and more preferably about 2 to 40, from the viewpoint of interaction with the ionic liquid. When the added mole number of the oxyalkylene unit is less than 1, it is difficult to balance the compatibility with the ionic liquid and the base polymer, and the bleeding to the adherend tends to increase. On the other hand, when the added mole number of the oxyalkylene unit exceeds 50, the ionic liquid is restrained by the ethylene oxide group and the antistatic property tends to be lowered.

  Specific examples of the ether type surfactant include trade names “Adekaria soap NE-10”, “Adekaria soap SE-10N”, “Adekaria soap SE-20N”, “Adekaria soap” manufactured by ADEKA Corporation. "ER-10", "Adekalia Soap SR-10", "Adekalia Soap SR-20", trade name "Emulgen 120" manufactured by Kao Corporation, trade name "Neugen" manufactured by Daiichi Kogyo Seiyaku Co., Ltd. EA130T "and the like.

  As the molecular weight of the ether group-containing compound, those having a number average molecular weight of 10,000 or less, preferably 200-5000 are suitably used. When the number average molecular weight exceeds 10,000, the contamination of the adherend tends to deteriorate. The number average molecular weight is obtained by measurement by GPC (gel permeation chromatography). The ether group-containing compound may be used alone or in combination of two or more.

  As a compounding quantity of an ether group containing compound, it is about 0.01-10 weight part with respect to 100 weight part of base polymers, Preferably it is about 0.05 weight part-5 weight part. When the blending amount of the ether group-containing compound is less than 0.01 parts by weight, sufficient charging characteristics tend to be difficult to obtain. On the other hand, when the compounding amount of the ether group-containing compound exceeds 10 parts by weight, the contamination of the adherend tends to increase.

  Moreover, the compound which produces keto-enol tautomerism can be added to the adhesive composition of this invention. By adding this compound, the gelation of the pressure-sensitive adhesive composition can be suppressed, and the effect of extending the pot life of the pressure-sensitive adhesive composition can be obtained.

  Examples of the compound causing keto-enol tautomerism include acetylacetone, 2,4-hexanedione, 3,5-heptanedione, 2-methylhexane-3,5-dione, 6-methylheptane-2,4- Dione, 2,6-dimethylheptane-3,5-dione; acetoacetate such as methyl acetoacetate, ethyl acetoacetate, isopropyl acetoacetate, tert-butyl acetoacetate; methyl propionyl acetate, ethyl propionyl acetate, isopropyl propionyl acetate, Examples include propionyl acetate such as propionyl acetate-tert-butyl; isobutyryl acetate such as methyl isobutyryl acetate, ethyl isobutyryl acetate, isopropyl isobutyryl acetate, isobutyryl acetate-tert-butyl; and malonic acid ester. Of these, acetylacetone and acetoacetate are preferably used.

(Base material)
Examples of the base material used in the pressure-sensitive adhesive sheet with a base material include a base material made of a porous material such as paper and nonwoven fabric, a plastic base material such as a polyester film, a rubber base material such as a rubber sheet, and a foam base such as a foam sheet. Materials and the like.

  In particular, when the adhesive sheet is used as a surface protective film, a plastic substrate is preferably used as the substrate. The plastic substrate is not particularly limited as long as it can be formed into a sheet shape or a film shape. For example, polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, ethylene Polypropylene film such as propylene copolymer, ethylene / 1-butene copolymer, ethylene / vinyl acetate copolymer, ethylene / ethyl acrylate copolymer, ethylene / vinyl alcohol copolymer, polyethylene terephthalate, polyethylene naphthalate, Polyester film such as polybutylene terephthalate, polyacrylate film, polystyrene film, nylon 6, nylon 66, polyamide film such as partially aromatic polyamide; polyvinyl chloride film, polyvinylidene chloride film, polycarbonate Irumu, and the like.

  When the pressure-sensitive adhesive sheet is used for bonding members, the thickness of the substrate is usually 1 to 2000 μm, preferably 5 to 1000 μm, more preferably 5 to 500 μm, still more preferably 5 to 300 μm, and most preferably 10 to 10 μm. 100 μm. When using an adhesive sheet as a surface protection film, the thickness of a base material is 5-200 micrometers normally, Preferably it is about 10-100 micrometers.

  For plastic substrates, if necessary, silicone-based, fluorine-based, long-chain alkyl-based or fatty acid amide-based release agents, mold release with silica powder, etc., acid treatment, acid treatment, alkali treatment, primer treatment, Anti-adhesive treatment such as corona treatment, plasma treatment and ultraviolet treatment, and antistatic treatment such as coating type, kneading type and vapor deposition type can also be performed. The plastic substrate used for the surface protective film is preferably subjected to antistatic treatment.

  The antistatic treatment applied to the plastic substrate is not particularly limited. For example, a method of providing an antistatic layer on at least one side of the substrate or a method of kneading a kneading type antistatic agent into the plastic substrate is used.

  As a method of providing an antistatic layer, an antistatic resin comprising an antistatic agent and a resin component, a conductive polymer, or a conductive resin containing a conductive substance is diluted with a solvent such as an organic solvent or water, and this coating liquid is used. And a method of depositing or plating a conductive substance on a plastic substrate and drying.

  Examples of the antistatic agent contained in the antistatic resin include cationic antistatic agents having cationic functional groups such as quaternary ammonium salts, pyridinium salts, primary, secondary, and tertiary amino groups, Amphoteric charging such as anionic antistatic agents having anionic functional groups such as sulfonates, sulfates, phosphonates, phosphates, alkylbetaines and their derivatives, imidazolines and their derivatives, alanines and their derivatives Nonionic antistatic agents such as inhibitors, amino alcohols and derivatives thereof, glycerin and derivatives thereof, polyethylene glycol and derivatives thereof, and monomers having the above-described cationic, anionic and zwitterionic ion conductive groups An ion conductive polymer obtained by polymerizing or copolymerizing the above.

  Cationic antistatic agents include (meth) acrylates having a quaternary ammonium group such as alkyltrimethylammonium salt, acyloylamidopropyltrimethylammonium methosulfate, alkylbenzylmethylammonium salt, acylcholine chloride, polydimethylaminoethyl methacrylate, etc. Examples thereof include a copolymer, a styrene copolymer having a quaternary ammonium group such as polyvinylbenzyltrimethylammonium chloride, and a diallylamine copolymer having a quaternary ammonium group such as polydiallyldimethylammonium chloride.

  Examples of the anionic antistatic agent include alkyl sulfonate, alkyl benzene sulfonate, alkyl sulfate ester salt, alkyl ethoxy sulfate ester salt, alkyl phosphate ester salt, and sulfonic acid group-containing styrene copolymer.

  Examples of zwitterionic antistatic agents include alkylbetaines, alkylimidazolium betaines, and carbobetaine graft copolymers.

  Nonionic antistatic agents include fatty acid alkylolamide, di- (2-hydroxyethyl) alkylamine, polyoxyethylene alkylamine, fatty acid glycerin ester, polyoxyethylene glycol fatty acid ester, sorbitan fatty acid ester, polyoxysorbitan fatty acid Examples thereof include esters, polyoxyethylene alkyl phenyl ethers, polyoxyethylene alkyl ethers, polyethylene glycols, polyoxyethylene diamines, copolymers composed of polyethers, polyesters and polyamides, and methoxypolyethylene glycol (meth) acrylates.

  Examples of the conductive polymer include polyaniline, polypyrrole, and polythiophene.

  Examples of conductive materials include tin oxide, antimony oxide, indium oxide, cadmium oxide, titanium oxide, zinc oxide, indium, tin, antimony, gold, silver, copper, aluminum, nickel, chromium, titanium, iron, cobalt, and iodide. Copper and their alloys or mixtures may be mentioned.

  As the resin component used for the antistatic resin and the conductive resin, general-purpose resins such as polyester, acrylic, polyvinyl, urethane, melamine, and epoxy are used. In addition, when using a polymer type antistatic agent, it is not necessary to contain a resin component. Further, the antistatic resin component may contain a methylol- or alkylol-containing melamine-based, urea-based, glyoxal-based, acrylamide-based compound, epoxy compound, or isocyanate-based compound as a crosslinking agent.

  Examples of the organic solvent include methyl ethyl ketone, acetone, ethyl acetate, tetrahydrofuran, dioxane, cyclohexanone, n-hexane, toluene, xylene, methanol, ethanol, n-propanol, and isopropanol. These can be used alone or in combination. As the coating method, known coating methods are used, and specific examples include roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating, impregnation and curtain coating methods.

  The thickness of the antistatic layer formed of the antistatic resin, conductive polymer and conductive resin is usually about 0.01 to 5 μm, preferably about 0.03 to 1 μm.

  Examples of the method for depositing or plating the conductive substance include vacuum deposition, sputtering, ion plating, chemical vapor deposition, spray pyrolysis, chemical plating, and electroplating. The thickness of the conductive material layer is usually 20 to 10,000 mm, preferably 50 to 5000 mm.

  As the kneading type antistatic agent, the above-mentioned antistatic agent is appropriately used. The compounding amount of the kneading type antistatic agent is 20% by weight or less, preferably 0.05 to 10% by weight based on the total weight of the plastic substrate. The kneading method is not particularly limited as long as the antistatic agent can be uniformly mixed with the resin used as the plastic substrate. Generally, a heating roll, a Banbury mixer, a pressure kneader, a biaxial kneader Etc. are used.

  On one side of the plastic substrate, if necessary, release agent with silicone, fluorine, long chain alkyl or fatty acid amide, release with silica powder, antifouling treatment, acid treatment, alkali treatment, primer Easy adhesion treatment such as treatment, corona treatment, plasma treatment, and ultraviolet treatment can also be performed.

(Adhesive layer)
The pressure-sensitive adhesive layer is, for example, a film-like pressure-sensitive adhesive having a desired thickness and area by applying and drying a coating agent containing the ionic liquid and the pressure-sensitive adhesive composition on an appropriate separator (such as release paper). A layer can be obtained easily. In the case of the pressure-sensitive adhesive sheet with a substrate, the pressure-sensitive adhesive layer may be formed by applying and drying on the substrate instead of the separator. As a method for applying the coating agent containing the pressure-sensitive adhesive composition, known methods used for the production of pressure-sensitive adhesive sheets are used. Specifically, roll coating, gravure coating, reverse coating, roll brushing, spray coating, air knife coating method. Etc. The pressure-sensitive adhesive layer may be either a single layer or multiple layers.

  The thickness of the said adhesive layer is not specifically limited, For example, about 3-100 micrometers, Preferably it is about 5-50 micrometers.

[Separator]
In the separator according to the present invention, after forming water droplets on at least one side of the separator base material, an organic solvent solution containing a release agent is applied on the surface of the separator base material on which water droplets are formed. The solvent and water droplets are removed, and the release agent is dried and / or cured to form a release agent layer having a concavo-convex shape on the surface.

  An uneven shape (uneven structure) is formed on the surface of the release agent layer. After forming water droplets on at least one surface of the separator substrate, an organic solvent solution containing a release agent is applied and the water droplets are maintained. This is because the organic solvent is removed by evaporation, and the water droplets are removed and the release agent is dried and / or cured in a state where the uneven shape is maintained.

  In the separator obtained by such a production method, a release agent layer may be provided on one side of the separator substrate, and the surface of the release agent layer may be provided with an uneven shape, and the release agent layer is provided on both sides of the separator base. An uneven shape may be provided on both surfaces of the release agent layer provided on both sides, and one of the release agent layer surfaces of the release agent layers provided on both sides of the separator base. The concave / convex shape may be provided only on the surface.

(paint remover)
The release agent used in the present invention can form a film (for example, a cured film, a dried film, etc.) on the separator base material to be applied, and the film is appropriately peeled according to the application. There is no particular limitation as long as it can exert its properties and does not adversely affect the pressure-sensitive adhesive layer. For example, a silicone release agent, a fluorine release agent, a long-chain alkyl release An agent, a polyolefin-based release agent, or the like can be used. Moreover, what is described in pages 103-130 of the adhesive handbook 3rd edition (adhesive sheet industry association edition) can also be used. In addition, a release agent can be used individually or in combination of 2 or more types.

  Moreover, as a peeling agent, from a viewpoint of exhibiting the outstanding peeling characteristic (light peeling property) with respect to the adhesive layer surface of an adhesive sheet, peeling force is about 0-25N / 50mm, Preferably it is 0.1-10N / 50mm. It is preferable to be able to form a film having a thickness of about 0.1 to 5 N / 50 mm, and most preferably about 0.1 to 1 N / 50 mm.

  As the release agent of the present invention, a silicone release agent is suitably used in that it is a solvent type, so that it can be easily dissolved in an organic solvent, can easily prepare a release agent solution, and has excellent release characteristics.

  Among silicone-based release agents, in particular, it can exhibit light release properties, and forms a release film by curing by addition reaction type crosslinking (curing reaction) by heat, and exhibits useful release characteristics. A thermosetting addition type silicone release agent (thermosetting addition type polysiloxane release agent) that can be used is preferable. The thermosetting addition-type silicone release agent comprises a polyorganosiloxane containing an alkenyl group as a functional group in the molecule (alkenyl group-containing silicone) and a polyorganosiloxane containing a hydrosilyl group as a functional group in the molecule. It is an essential component.

  The polyorganosiloxane having an alkenyl group as a functional group in the molecule is preferably a polyorganosiloxane having two or more alkenyl groups in the molecule. Examples of the alkenyl group include a vinyl group (ethenyl group), an allyl group (2-propenyl group), a butenyl group, a pentenyl group, and a hexenyl group. Among them, a vinyl group and a hexenyl group are preferable. The alkenyl group is usually bonded to a silicon atom (for example, a terminal silicon atom or a silicon atom inside the main chain) of the polyorganosiloxane forming the main chain or skeleton.

  Examples of the polyorganosiloxane forming the main chain or skeleton include polyalkylalkylsiloxanes such as polydimethylsiloxane, polydiethylsiloxane, and polymethylethylsiloxane, polyalkylarylsiloxanes, and silicon atom-containing monomers. Examples thereof include a copolymer [for example, poly (dimethylsiloxane-diethylsiloxane)] in which a plurality of components are used. Of these, polydimethylsiloxane is preferred in that stable peelability can be obtained. Specific examples of the polyorganosiloxane having an alkenyl group as a functional group in the molecule include polydimethylsiloxane having a vinyl group as a functional group, polydimethylsiloxane having a hexenyl group as a functional group, and mixtures thereof. Is done.

  The polyorganosiloxane containing a hydrosilyl group as a functional group in the molecule is a polyorganosiloxane having a hydrogen atom bonded to a silicon atom (particularly a silicon atom having a Si-H bond) in the molecule. In particular, polyorganosiloxane having two or more silicon atoms having Si—H bonds in the molecule is preferable. The silicon atom having a Si—H bond may be either a silicon atom in the main chain or a silicon atom in the side chain, that is, it may be contained as a constituent unit of the main chain. It may be included as a structural unit. The number of silicon atoms in the Si—H bond is not particularly limited as long as it is 2 or more. Specific examples of the polyorganosiloxane containing a hydrosilyl group as a functional group in the molecule are polymethylhydrogensiloxane and poly (dimethylsiloxane-methylhydrogensiloxane).

  Further, in the present invention, the release agent needs to temporarily hold the uneven shape formed by water droplets when the organic solvent has evaporated, so it contains a solid [viscoelastic body (rubber-like substance) at room temperature. ] Is preferable. It may be liquid before curing as long as it is a curable release agent, but it has a high viscosity (10 [Pa · s] or more, 23 ° C.) to the extent that the uneven shape formed by water droplets can be temporarily retained. It is preferable. If the release agent can be cured by heating for a short time, the uneven shape formed by water droplets can be maintained even if the viscosity is relatively low (less than 10 [Pa · s], 23 ° C.). When the viscosity is less than [Pa · s] (23 ° C.), it is almost difficult to maintain the uneven shape.

In addition, a viscosity is measured on condition of the following based on JISZ8803.
Rotational viscometer: BM type rotor No. : No. 4
Rotation speed: 30rpm
Measurement temperature: 25.0 ± 0.5 ° C

  A reaction inhibitor may be added to the release agent of the present invention in order to impart storage stability at room temperature. For example, when a thermosetting addition type silicone release agent is used as the release agent, examples of the reaction inhibitor include 3,5-dimethyl-1-hexyn-3-ol, 3-methyl-1-pentene-3- All, 3-methyl-3-penten-1-yne, 3,5-dimethyl-3-hexen-1-yne, and the like.

  In addition to the reaction inhibitor, a release control agent or the like may be added to the release agent as necessary. For example, when a thermosetting addition-type silicone release agent is used as the release agent, specifically, a release control agent such as MQ resin, a polyorganosiloxane having no alkenyl group or hydrosilyl group (trimethylsiloxy group end-blocking poly). Dimethylsiloxane etc.) may be added.

  Although content of other components, such as the said reaction inhibitor and peeling control agent with respect to a thermosetting addition type silicone type release agent, is not specifically limited, For example, about 1 to 30 weight% is preferable.

  In the present invention, a platinum catalyst generally used as a catalyst for a thermosetting addition-type silicone release agent (in particular, at least selected from chloroplatinic acid, platinum olefin complexes, and chloroplatinic acid olefin complexes). One platinum-based catalyst) is preferably added. By adding a platinum catalyst to the thermosetting addition type silicone release agent, the curing rate of the release agent can be accelerated.

  Furthermore, various additive components (additives) may be used for the release agent as necessary. Although it does not specifically limit as an additive component, For example, a filler, an antistatic agent, antioxidant, a ultraviolet absorber, a plasticizer, a coloring agent (dye, pigment, etc.) etc. are illustrated.

(Organic solvent)
The organic solvent for dissolving the release agent is not particularly limited as long as it can uniformly dissolve the release agent. For example, hydrocarbon solvents such as cyclohexane, hexane, and heptane; aromatics such as toluene and xylene Group solvents; ester solvents such as ethyl acetate and methyl acetate; ketone solvents such as acetone and methyl ethyl ketone; alcohol solvents such as methanol, ethanol and butanol. An organic solvent may be used independently and may be used as a mixed solvent which mixed 2 or more types.

  In the present invention, when an organic solvent that is harder to evaporate than water is used, the water droplets evaporate before the organic solvent evaporates, and the moldability of the recesses due to the water droplets deteriorates. In the relative evaporation rate of 1.0, those having a relative evaporation rate greater than the relative evaporation rate of water (0.38), particularly those having a relative evaporation rate of 1.0 or more are preferable. Examples of such an organic solvent include hexane, heptane, toluene, xylene, ethyl acetate, methyl ethyl ketone (MEK), and the like.

  The relative evaporation rate is an evaporation rate measured according to ASTM-D3539. Specifically, the evaporation time of n-butyl acetate and the evaporation time of each test solvent in dry air at 25 ° C. It is expressed by the ratio of The relative evaporation rates of various organic solvents are described in Table 5 on page 17-19 of “Latest Coating Technology” (published by General Technology Center, 1983).

(Release agent solution)
The release agent solution of the present invention is a solution in which a release agent is dissolved in an organic solvent, and is prepared by dissolving the release agent in an organic solvent. If the viscosity of the release agent solution is too high, the shape of the water droplets may be disturbed when the release agent solution is applied. Therefore, the viscosity is 3 [Pa · s] or less, especially 1 [Pa · s] or less, especially 0 0.5 [Pa · s] or less is preferable. On the other hand, if the viscosity of the release agent solution is too low, the release agent solution coating film tends to flow on the separator base material, making it difficult to apply to the separator base material, and therefore, 5 [mPa · s] or more, It is preferably 10 [mPa · s] or more, particularly 20 [mPa · s] or more.

  If the concentration of the release agent in the release agent solution is too high, the organic solvent may evaporate before the recesses are formed by the water droplets. The range of 20 [% by weight] is preferable. Note that the concentration of the release agent in the release agent solution usually increases when the concentration of the release agent in the release agent solution increases, so it is important to control the viscosity to be within the above range.

(Separator base material)
The base material (separator base material) constituting the separator of the present invention is not particularly limited, and can be appropriately selected from those conventionally used as base materials in separators. Examples of such a substrate include paper substrates such as glassine paper, coated paper, and cast coated paper, laminated paper obtained by laminating a thermoplastic resin such as polyethylene on these paper substrates, and a plastic film (thermoplastic resin film). ) And the like.

  When using a paper substrate as the separator substrate, it is preferable to laminate a plastic such as polyethylene or to apply a primer to prevent the penetration of the release agent solution (coating solution). . Further, the uneven shape of the separator surface is easily affected by the unevenness of the paper substrate. Therefore, a plastic film (plastic base material) is preferable as the separator base material in the present invention.

  Examples of the plastic film material (thermoplastic resin) include polyethylene (PE), polypropylene (PP), polymethylpentene (PMP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), and the like. Olefin resin containing α-olefin as monomer component; Polyester resin such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT); Polyvinyl chloride (PVC); Vinyl acetate resin; Polyamide (PC); Polyphenylene sulfide (PPS); Amide resins such as polyamide (nylon) and wholly aromatic polyamide (aramid); Polyimide resins; Polyetheretherketone (PEEK) and the like. These materials can be used alone or in combination of two or more. Of these, polyester films such as PET and PEN, polyolefin films such as PP and PMP, polycarbonate films, polyvinyl acetate films, etc. are preferable. Polyethylene terephthalate (PET) and polypropylene are particularly preferable from the viewpoint of strength, heat resistance, cost, and the like. (PP) is preferred.

  Although the thickness of a separator base material is not specifically limited and can be suitably selected according to a use, a use purpose, etc., For example, it is about 5-250 micrometers, Preferably it is about 10-100 micrometers. The separator substrate may have a single layer form or may have a laminated form.

(Manufacturing method of separator)
The separator of the present invention in which the release agent layer provided with the uneven shape is provided on at least one surface of the separator substrate can be produced through the following steps (i) to (iii). That is,
(i) A step of forming water droplets on at least one surface of the separator substrate (a step of obtaining a water droplet formation surface on the separator substrate)
(ii) A step of forming a release agent layer by applying a release agent solution (coating liquid) to the water droplet formation surface (a step of forming a release agent solution application surface by applying a release agent solution to the water drop formation surface )
(iii) A step of removing the organic solvent and water droplets, drying and / or curing the release agent, and forming a release agent layer having an uneven shape on the surface

  The step (i) is a step of forming fine water droplets on the separator base material that serve as a mold for forming the uneven shape on the surface of the release agent layer. It is presumed that the water droplets form a concavo-convex shape because water is not compatible with the release agent solution which is a solution obtained by dissolving the release agent in an organic solvent. Examples of the method of forming water droplets on at least one surface of the separator substrate in the step (i) include a method of dew condensation by humidification and a method of spraying water.

  The method of dew condensation by humidification is not particularly limited, but, for example, a method of humidifying by introducing steam generated by a steam iron or the like in an atmosphere capable of being humidified, or an atmosphere of water vapor generated from a humidifier. The method etc. which introduce | transduce in are mentioned. In the case of continuous production, a method of blowing humid air can be used. Such a method can be effectively used when a small amount of separator is manufactured.

  Although it does not restrict | limit especially as a method of spraying water, For example, the method of spraying the mist generated with the sprayer etc. directly on the separator base material surface etc. is mentioned. If the method of spraying water is used, a larger uneven shape can be formed more easily. In addition, since the variation in the size of the water droplets is large in this method, the size of the recess formed by the water droplets tends to be large, but the separator base is formed in a shorter time than the method in which the coating surface is condensed by the humidification. Since water droplets can be formed on the surface of the material, this method is effective when it is desired to increase the production speed.

  FIG. 1 is a schematic cross-sectional view showing an example of the state after completion of the step (i), where 1 is a separator substrate and 2 is a water droplet.

  In the step (ii), the release agent solution is applied to the surface of the separator substrate that has condensed, and the release agent solution is surrounded by the water droplets in contact with the separator substrate (water droplets are exposed on the release agent layer surface). And a state in which the head of the water droplet and its vicinity are protruding from the release agent layer while the water droplet is in contact with the separator substrate.

  Any coating method can be used as a coating method (coating method) of the release agent solution used in the step (ii). When making a small-area separator, it can be hand-painted using a baker-type applicator, doctor blade, bar coater or the like. In addition, when coating continuously with a coating machine, it is possible to select and use a coating machine as appropriate according to the coating amount. For example, a reverse coater, direct gravure coater, direct bar coater, reverse bar Coating machines such as coaters and die coaters can be used.

  In the step (ii), the thickness of the release agent layer obtained by applying the release agent solution (application thickness of the release agent solution) is the thickness when dried and / or cured without forming water droplets. In this case, for example, it is about 1 to 100 μm (preferably about 2 to 50 μm). When the thickness of the release agent layer is reduced (for example, 5 μm or less), a relatively small uneven shape is formed. And the uneven | corrugated shape formed tends to become large as the thickness of the release agent layer is increased. Note that the thickness of the release agent layer is not limited to the above range, and a release agent layer having an uneven shape with a desired size can be obtained by adjusting according to the purpose.

  In the step (ii), it is important to immediately apply the release agent solution onto the water droplet forming surface of the separator substrate after forming the water droplets on the separator substrate. In the case of continuous production, it is preferable that the step (i) (water droplet formation step) and the step (ii) (release agent solution coating step) are sequentially performed in-line. This is because if the release agent solution is not applied before the water droplets evaporate, it becomes difficult to form the uneven shape caused by the water droplets.

  FIG. 2 is a schematic cross-sectional view showing an example of the state after completion of the step (ii), wherein 1 is a separator substrate, 2 is a water droplet, and 3 is a release agent layer. In FIG. 2, the entire water droplet is covered with the release agent layer. However, in the present invention, after the step (ii), the head of the water drop and the vicinity of the head may be exposed from the release agent layer. .

  In the step (iii), the organic solvent and water droplets are removed by drying (for example, high-temperature heating) and the release agent is dried (and cured if necessary), and the release agent obtained in the step (ii). The layer (release agent layer before curing) becomes a release agent layer (cured film) having an uneven shape on the surface. In the step (iii), the uneven shape is formed on the surface of the release agent layer. By removing the water droplets covered with the release agent layer, a void is generated in the layer, and the release agent is removed. A through-hole as a recess is formed by sinking into the cavity or removing water droplets covered with a release agent layer with the head and the vicinity of the head protruding out of the layer. It is thought that.

  In the step (iii), since it is necessary to evaporate water (water droplets), it is preferable to dry at a temperature of 100 ° C. or higher. When a thermosetting addition type silicone release agent is used as the release agent, it is preferable to heat at a temperature of 100 ° C. or higher from the viewpoint of the curability of the silicone. However, when the heat resistance of the separator substrate is low, it is necessary not to raise the heating temperature too much. For example, when a polyethylene terephthalate substrate is used as the separator substrate, 140 ° C. or lower (in particular, 130 ° C. or lower) is preferable. When the heating temperature exceeds 140 ° C., the generation of wrinkles due to heat shrinkage tends to increase. The heating time can be appropriately adjusted according to conditions such as the type of release agent, the amount of water droplets, and the heating temperature.

  FIG. 3 is a schematic cross-sectional view showing an example of the state in the first drying stage of the step (iii), and shows a state in which an organic solvent that is easily evaporated evaporates first and water droplets still remain. In FIG. 3, 1 is a separator substrate, 2 is a water droplet, and 31 is a release agent layer from which an organic solvent has evaporated.

  In the step (iii), the water droplets covered with the release agent layer after the completion of the step (ii) are first evaporated, and the organic solvent that easily evaporates as the drying proceeds. The vicinity of the head may be exposed. In the step (iii), water droplets may float during heat drying, and the release agent solution constituting the release agent layer may enter between the water droplets and the separator substrate.

  In the present invention, since the diameter of the concave-convex concave portion on the surface of the release agent layer of the separator can be controlled by the size of the water droplet formed in the step (i), it is possible to form concave-convex with a wide range of diameters. is there.

  For example, when forming water droplets by the method of condensing the separator substrate surface by humidification in the step (i), a relatively small recess can be formed, about 0.1 μm for a small one and about 100 μm for a large one. It is possible to size. In the case of forming water droplets by the method of spraying water in the step (i), a relatively large recess can be formed, and a size of about 10 μm can be used for a small one and a size of about 3 mm for a large one.

  The separator of the present invention is excellent in productivity because it can impart an uneven shape to the surface of the release agent layer in the process of drying and / or curing the release agent. Moreover, since the separator of this invention has uneven | corrugated shape on the surface of a releasing agent layer, it is excellent in peelability compared with the separator which has not provided the uneven | corrugated shape. In addition, since it is manufactured by the above method, a uniform release agent layer having a concavo-convex shape can be formed, and a stable release property can be obtained. The recess on the surface of the release agent layer may be a hole penetrating the release agent layer. FIG. 4 is a schematic cross-sectional view showing an example of the separator obtained in the present invention. In FIG. 4, 1 is a separator substrate, 4 is a release agent layer from which water droplets are evaporated, and 5 is a separator.

[Method for producing adhesive sheet]
The method for producing a pressure-sensitive adhesive sheet with a separator according to the present invention comprises a separator base on at least one side of a pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive composition containing a polymer having a glass transition temperature (Tg) of 0 ° C. or less as an ionic liquid and a base polymer. After water droplets are formed on at least one side of the material, an organic solvent solution containing a release agent is applied to the surface of the separator substrate on which the water droplets are formed, and then the organic solvent and water droplets are removed and peeled off. A separator having a release agent layer having an uneven shape formed on the surface by drying and / or curing the agent is bonded.

  Since the separator is efficiently produced by a simple method as described above, and the obtained separator is bonded to the surface of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet, the pressure-sensitive adhesive sheet with a separator of the present invention is excellent in productivity.

  Since the pressure-sensitive adhesive sheet of the present invention produced by such a method contains a non-volatile ionic liquid in the pressure-sensitive adhesive layer, it is possible to neutralize the bias of charge generated by peeling, and the effect thereof is a function of time. Will not fade. Therefore, it is possible to prevent static electricity from being generated when the separator is peeled off from an optical member such as a polarizing plate, or when the separator is peeled off from the pressure-sensitive adhesive sheet or the surface protective film. In a display panel, the liquid crystal cell can be suitably used for a purpose of bonding a liquid crystal cell to an optical member such as a polarizing plate or a wavelength plate, a surface protective film, or the like.

  Furthermore, in the pressure-sensitive adhesive sheet of the present invention, a convex structure (protrusion structure) is formed on the surface of the pressure-sensitive adhesive layer protected by the separator due to the uneven shape on the surface of the release agent layer of the separator. For this reason, the pressure-sensitive adhesive sheet of the present invention is excellent in air detachability, and even if bubbles are generated between the adherend and the adherend during application, the generated bubbles (air) can be removed neatly, so that the attachment is performed again. There is no need. Moreover, since the area which touches a to-be-adhered body is reduced by the convex structure of the adhesive layer surface, re-sticking and correction of a sticking position can be performed easily.

  The pressure-sensitive adhesive sheet with a separator of the present invention can be used for a well-known and commonly used pressure-sensitive adhesive sheet, and is suitably used as, for example, a double-sided pressure-sensitive adhesive sheet, a surface-protective pressure-sensitive adhesive sheet, and an electronic component pressure-sensitive adhesive sheet.

  Examples and the like specifically showing the configuration and effects of the present invention will be described below. In addition, the evaluation item in an Example etc. measured as follows.

[Acid value]
The acid value was measured using an automatic titration apparatus (trade name “COM-550”, manufactured by Hiranuma Sangyo Co., Ltd.) and determined from the following formula.
A = {(Y−X) × f × 5.611} / M
[A: acid value, Y: titration of sample solution (ml), X: titration of solution containing only 50 g of mixed solvent (ml), f: factor of titration solution, M: weight of polymer sample (g)]
The measurement conditions are as follows.
Sample solution: About 0.5 g of a polymer sample was dissolved in 50 g of a mixed solvent [toluene / 2-propanol / distilled water = 50 / 49.5 / 0.5 (weight ratio)] to obtain a sample solution.
Titration solution: 0.1 N, 2-propanol potassium hydroxide solution (manufactured by Wako Pure Chemical Industries, Ltd., for petroleum product neutralization test)
Electrode: Glass electrode; GE-101, Comparative electrode; RE-201
Measurement mode: Petroleum product neutralization number test 1

[Molecular weight]
The molecular weight was measured using a GPC apparatus (trade name “HLC-8220GPC”, manufactured by Tosoh Corporation), and determined in terms of polystyrene.
The measurement conditions are as follows.
Sample concentration: 0.2 wt% (THF solution)
Sample injection volume: 10 μl
Eluent: THF
Flow rate: 0.6 ml / min
Measurement temperature: 40 ° C
Column: Sample column; 1 TSKguardcolumn SuperHZ-H + 2 TSKgel SuperHZM-H Reference column; 1 TSKgel SuperH-RC Detector: Differential refractometer

[Measurement of glass transition temperature]
The glass transition temperature (Tg) (° C.) of the acrylic polymer obtained in Production Examples 1 to 4 was determined by dynamic viscoelasticity measurement according to the following procedure.
A sheet of acrylic polymer having a thickness of 20 μm was laminated to a thickness of about 2 mm, and this was punched to φ7.9 mm to produce a cylindrical pellet, which was used as a glass transition temperature (Tg) measurement sample.
Using the measurement sample, the measurement sample was fixed to a jig having a φ7.9 mm parallel plate, and the loss elastic modulus G ″ was measured by a dynamic viscoelasticity measuring device (trade name “ARES”, manufactured by Rheometrics). The temperature dependency was measured, and the temperature at which the obtained G ″ curve was maximized was defined as the glass transition temperature (Tg) (° C.).
The measurement conditions are as follows.
Measurement: Shear mode Temperature range: -70 ° C to 150 ° C
Temperature increase range: 5 ° C / min
Frequency: 1Hz

[NMR]
NMR measurement was performed using a nuclear magnetic resonance apparatus (trade name “EX-400”, manufactured by JEOL Ltd.).
The measurement conditions are as follows.
Observation frequency: 400 MHz ( ¹ H), 100 MHz ( ¹³ C)
Measuring solvent: actone-d ₆
Measurement temperature: 23 ° C

[XRF]
XRF measurement was performed using a fluorescent X-ray analyzer (trade name “ZSX-100e”, manufactured by Rigaku Corporation).
The measurement conditions are as follows.
Measuring method: filter paper method X-ray source: Rh

[FT-IR]
The FT-IR measurement was performed using a Fourier transform infrared spectrophotometer (trade name “Magna-560”, manufactured by Nicolet).
The measurement conditions are as follows.
Measuring method: ATR method Detector: DTGS
Resolution: 4.0cm ^-1
Integration count: 64 times

[Preparation of acrylic polymer]
Production Example 1: Acrylic polymer (A)
200 parts by weight of 2-ethylhexyl acrylate, 8 parts by weight of 2-hydroxyethyl acrylate, 2,2′- as a polymerization initiator in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas inlet tube, a cooler, and a dropping funnel Charge 0.4 parts by weight of azobisisobutyronitrile and 312 parts by weight of ethyl acetate, introduce nitrogen gas while gently stirring, perform the polymerization reaction for 6 hours while keeping the liquid temperature in the flask at around 65 ° C., A solution (40% by weight) of acrylic polymer (A) was prepared. The acrylic polymer (A) had a glass transition temperature (Tg) of −10 ° C. or lower, a weight average molecular weight of 500,000, and an acid value of 0.

Production Example 2: Acrylic polymer (B)
200 parts by weight of 2-ethylhexyl acrylate, 8 parts by weight of acrylic acid, and 2,2′-azobisiso as a polymerization initiator in a four-necked flask equipped with a stirring blade, a thermometer, a nitrogen gas inlet tube, a condenser, and a dropping funnel Acrylic polymer was prepared by adding 0.4 parts by weight of butyronitrile and 312 parts by weight of ethyl acetate, introducing nitrogen gas with gentle stirring, and maintaining the liquid temperature in the flask at around 65 ° C. for 6 hours. A solution (40% by weight) of (B) was prepared. This acrylic polymer (B) had a glass transition temperature (Tg): −10 ° C. or lower, a weight average molecular weight: 540,000, and an acid value: 30.

Production Example 3: Acrylic polymer (C)
In a four-necked flask equipped with a stirring blade, thermometer, nitrogen gas inlet tube, condenser, and dropping funnel, 180 parts by weight of 2-ethylhexyl acrylate, 20 parts by weight of ethoxy-diethylene glycol acrylate, 8 parts by weight of 2-hydroxyethyl acrylate, polymerization As an initiator, 0.4 part by weight of 2,2′-azobisisobutyronitrile, 47 parts by weight of toluene, and 265 parts by weight of ethyl acetate were introduced, nitrogen gas was introduced while gently stirring, and the liquid temperature in the flask was adjusted. A polymerization reaction was carried out for 6 hours while maintaining at around 65 ° C. to prepare a solution (40% by weight) of an acrylic polymer (C). The acrylic polymer (C) had a glass transition temperature (Tg): −10 ° C. or lower, a weight average molecular weight: 510,000, and an acid value: 0.

Production Example 4: Acrylic polymer (D)
In a four-necked flask equipped with a stirring blade, thermometer, nitrogen gas inlet tube, cooler, and dropping funnel, 195 parts by weight of 2-ethylhexyl acrylate, nonionic reactive surfactant (trade name “ADEKA rear soap ER-10” ADEKA Co., Ltd.) 5 parts by weight, 2-hydroxyethyl acrylate 8 parts by weight, 2,2′-azobisisobutyronitrile 0.4 part by weight, ethyl acetate 312 parts by weight as a polymerization initiator Nitrogen gas was introduced into the flask while stirring, and the polymerization temperature was maintained at around 65 ° C. for 6 hours to prepare a solution (40% by weight) of an acrylic polymer (D). This acrylic polymer (D) had a glass transition temperature (Tg): −10 ° C. or lower, a weight average molecular weight: 680,000, and an acid value: 0.

[Preparation of ionic liquid]
Production Example 5: Ionic liquid (1)
After adding a 20 wt% aqueous solution of 10 parts by weight of 1-butyl-3-methylpyridinium chloride [manufactured by Wako Pure Chemical Industries, Ltd.] to a four-necked flask equipped with a stirring blade, a thermometer, and a condenser, stirring was performed. While rotating the blade, 19% by weight of a 20% by weight aqueous solution of lithium bis (trifluoromethanesulfone) imide [manufactured by Kishida Chemical Co., Ltd.] was gradually added. After the addition, stirring was continued at room temperature (25 ° C.) for 2 hours, and then allowed to stand for 12 hours. The supernatant was removed, and a liquid product was obtained in an atmosphere at 25 ° C. The obtained liquid product was washed three times with 200 parts by weight of distilled water and dried at a temperature of 110 ° C. for 2 hours to obtain 20 parts by weight of ionic liquid (1). The obtained ionic liquid (1) was subjected to NMR ( ¹ H, ¹³ C) measurement, FT-IR measurement, and XRf measurement to confirm that it was 1-butyl-3-methylpyridinium bis (trifluoromethanesulfone) imide. .

Production Example 6: Ionic liquid (2)
After adding 10 parts by weight of a diallyldimethylammonium chloride 60 wt% aqueous solution (manufactured by Tokyo Chemical Industry Co., Ltd.) to a four-necked flask equipped with a stirring blade, a thermometer, and a condenser, lithium bis (trifluoromethanesulfonyl) while turning the stirring blade Imide (manufactured by Kishida Chemical Co.) 13 parts by weight of 50% by weight aqueous solution was gradually added. After the addition, stirring was continued at 25 ° C. for 2 hours, and then allowed to stand for 12 hours. The supernatant was removed, and a liquid product was obtained in an atmosphere at 25 ° C. The obtained liquid product was washed with 200 parts by weight of distilled water three times and dried in an environment of 110 ° C. for 2 hours to obtain 13 parts by weight of a liquid ionic liquid (2) at 25 ° C. The obtained ionic liquid (2) was subjected to NMR ( ¹ H, ¹³ C) measurement, FT-IR measurement, and XRf measurement, and confirmed to be diallyldimethylammonium bis (trifluoromethanesulfonyl) imide.

Production Example 7: Antistatic agent solution (a)
In a four-necked flask equipped with a stirring blade, a thermometer, and a condenser, 5 parts by weight of ionic liquid (1), polypropylene glycol-polyethylene glycol-polypropylene glycol block copolymer (number average molecular weight: 2,000, ethylene glycol ratio: 50 wt%) and 5 parts by weight of ethyl acetate and 90 parts by weight of ethyl acetate were added, and the mixture was stirred for about 30 minutes while maintaining the liquid temperature in the flask at around 25 ° C. to prepare an antistatic agent solution (a) (10 wt%). .

[Preparation of separator]
Production Example 8: Separator (1)
The release agent solution was prepared with the following formulation.
(i) Thermosetting addition type silicone (trade name “KS-847T”, manufactured by Shin-Etsu Chemical Co., Ltd.) 30% by weight toluene solution
(ii) Platinum catalyst (trade name “PL-50T”, manufactured by Shin-Etsu Chemical Co., Ltd.) Toluene solution
(iii) Organic solvent: n-hexane Mixing ratio (i) / (ii) / (iii) = 100/1/200 (weight ratio)
The viscosity of the release agent solution was 77 [mPa · s].

  Put a base material (polyethylene terephthalate film with a thickness of 38 μm) in a humidification box (length: 30 cm x width: 45 cm x height: 30 cm) produced by surrounding a box assembled with angle materials with a polyethylene terephthalate sheet, Water was formed on the substrate by humidifying the inside of the humidification box with a steam generator for 1 minute. The ambient temperature was 23 ° C.

  Thickness such that the thickness of the release agent layer becomes 10 μm when the release agent solution is applied and dried without forming water droplets on the surface of the substrate on which the water droplets are formed using a baker type applicator. It was applied with.

  After coating, the separator (1) having a release agent-treated layer on one surface of the substrate was obtained by drying at a high temperature by heating at 120 ° C. for 1 minute using a hot air oven.

Production Example 9: Separator (2)
A separator (2) having a release agent-treated layer on one surface of the substrate is obtained in the same manner as the separator (1) except that water droplets are formed on the substrate using a spray bottle in an atmosphere at 23 ° C. It was.

Production Example 10: Separator (3)
A separator (3) having a release agent-treated layer on one surface of the substrate was obtained in the same manner as the separator (1) except that the step of forming water droplets on the substrate was not performed.

Example 1
(Preparation of adhesive composition)
A solution (40% by weight) of the acrylic polymer (A) was diluted to 20% by weight with ethyl acetate, 0.1 parts by weight of ionic liquid (1) was added to 100 parts by weight of this solution, and hexamethylene diisocyanate. 0.8 parts by weight of isocyanurate (trade name “Coronate HX”, manufactured by Nippon Polyurethane Industry Co., Ltd.) and 0.4 parts by weight of dibutyltin dilaurate (1% by weight ethyl acetate solution) as a crosslinking catalyst were added. An acrylic pressure-sensitive adhesive solution (1) was prepared.
(Preparation of adhesive sheet)
The obtained acrylic pressure-sensitive adhesive solution (1) was applied to one side of a polyethylene terephthalate film and heated at 110 ° C. for 3 minutes to form a pressure-sensitive adhesive layer having a thickness of 20 μm. Subsequently, the adhesive sheet 1 was produced by bonding the release agent-treated surface of the separator (1) to the adhesive layer.

Example 2
(Preparation of adhesive sheet)
The acrylic pressure-sensitive adhesive solution (1) was applied to one side of a polyethylene terephthalate film and heated at 110 ° C. for 3 minutes to form a pressure-sensitive adhesive layer having a thickness of 20 μm. Subsequently, the adhesive sheet 2 was produced by bonding the release agent-treated surface of the separator (2) to the adhesive layer.

Example 3
(Preparation of adhesive composition)
A solution (40% by weight) of acrylic polymer B was diluted to 20% by weight with ethyl acetate. To 100 parts by weight of this solution, 2.0 parts by weight of ionic liquid (2), Glycidylaminomethyl) cyclohexane (trade name “TETRAD-C”, manufactured by Mitsubishi Gas Chemical Co., Ltd.) 0.7 parts by weight, trimethylolpropane / tolylene diisocyanate trimer adduct (trade name “Coronate L ", manufactured by Nippon Polyurethane Industry Co., Ltd.) 0.3 parts by weight was added to prepare an acrylic pressure-sensitive adhesive solution (2).
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 3 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (2) was used in place of the acrylic pressure-sensitive adhesive solution (1).

Example 4
(Preparation of adhesive composition)
A solution (40% by weight) of the acrylic polymer (C) was diluted to 20% by weight with ethyl acetate, 0.2 parts by weight of ionic liquid (1) was added to 100 parts by weight of this solution, and hexamethylene diisocyanate. 0.4 parts by weight of isocyanurate (trade name “Coronate HX”, manufactured by Nippon Polyurethane Industry Co., Ltd.) and 0.4 parts by weight of dibutyltin dilaurate (1% by weight ethyl acetate solution) as a crosslinking catalyst were added. An acrylic pressure-sensitive adhesive solution (3) was prepared.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 4 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (3) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Example 5
(Preparation of adhesive composition)
An acrylic pressure-sensitive adhesive solution (4) was prepared in the same manner as in Example 4 except that the acrylic polymer (D) solution (40% by weight) was used instead of the acrylic polymer (C) solution (40% by weight). ) Was prepared.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 5 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (4) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Example 6
(Preparation of adhesive composition)
A solution (40% by weight) of the acrylic polymer (A) is diluted to 20% by weight with ethyl acetate, and 2 parts by weight of the antistatic agent solution (a) (10% by weight) is added to 100 parts by weight of this solution. Isocyanurate of isocyanate (trade name “Coronate HX”, manufactured by Nippon Polyurethane Industry Co., Ltd.) 0.8 part by weight, dibutyltin dilaurate (1% by weight ethyl acetate solution) as a crosslinking catalyst 0.4 An acrylic adhesive solution (5) was prepared by adding parts by weight.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 6 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (5) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Comparative Example 1
(Preparation of adhesive sheet)
The acrylic pressure-sensitive adhesive solution (1) was applied to one side of a polyethylene terephthalate film and heated at 110 ° C. for 3 minutes to form a pressure-sensitive adhesive layer having a thickness of 20 μm. Subsequently, the adhesive sheet 7 was produced by bonding the release agent-treated surface of the separator (3) to the adhesive layer.

Comparative Example 2
(Preparation of adhesive composition)
An acrylic pressure-sensitive adhesive solution (6) was prepared in the same manner as in Example 1 except that no ionic liquid was added.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 8 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (6) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Comparative Example 3
(Preparation of adhesive composition)
An acrylic pressure-sensitive adhesive solution (7) was prepared in the same manner as in Example 3 except that no ionic liquid was added.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 9 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (7) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Comparative Example 4
(Preparation of adhesive composition)
An acrylic pressure-sensitive adhesive solution (8) was prepared in the same manner as in Example 4 except that no ionic liquid was added.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 10 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (8) was used instead of the acrylic pressure-sensitive adhesive solution (1).

Comparative Example 5
(Preparation of adhesive composition)
An acrylic pressure-sensitive adhesive solution (9) was prepared in the same manner as in Example 5 except that the ionic liquid was not added.
(Preparation of adhesive sheet)
A pressure-sensitive adhesive sheet 11 was produced in the same manner as in Example 1 except that the acrylic pressure-sensitive adhesive solution (9) was used instead of the acrylic pressure-sensitive adhesive solution (1).

  About the adhesive sheets 1-11 obtained by the said Example, the comparative example, etc., the following conditions evaluated the stripping voltage, adhesive force, peeling force, and the shape of the release agent layer surface of a separator.

[Peeling voltage]
The pressure-sensitive adhesive sheets obtained in Examples and Comparative Examples were cut into a size of width 70 mm × length 100 mm and placed on a sample fixing base. One end of the separator in the pressure-sensitive adhesive sheet is fixed to an automatic winder, peeled in the length direction so that the peel angle is 150 ° and the peel speed is 10 m / min, and the potential of the pressure-sensitive adhesive layer surface is set at a predetermined position ( It measured using the electric potential measuring device (Brand name "KSD-0103", Kasuga Denki Co., Ltd. make) fixed to the adhesive layer surface 100 mm in height). The measurement was performed in an environment of 23 ° C. and 50% RH.

[Adhesion measurement]
A 80 μm-thick triacetyl cellulose film (trade name “Fujitac”, manufactured by Fuji Photo Film Co., Ltd.) was cut into a width of 70 mm and a length of 100 mm and immersed in an aqueous solution of sodium hydroxide (10% by weight) at 60 ° C. for 1 minute. Thereafter, the substrate was washed with distilled water to prepare an adherend. The obtained adherend was allowed to stand for 1 day in an environment of 23 ° C. and 50% RH, and then used as an adherend for adhesive force evaluation.
The pressure-sensitive adhesive sheets obtained in the examples and comparative examples were cut into a size of 25 mm wide × 80 mm long and laminated on the adherend for evaluating adhesive strength at a pressure of 0.25 MPa to prepare an evaluation sample.
After standing for 30 minutes after lamination, the adhesive sheet was peeled off at a pulling speed of 30 m / min and a peeling angle of 180 ° using a universal tensile tester (trade name “High Speed Peeling Tester”, manufactured by Tester Sangyo Co., Ltd.). The adhesive strength was measured. The measurement was performed in an environment of 23 ° C. × 50% RH.

[Measurement method of peeling force]
The pressure-sensitive adhesive sheets obtained in the examples and comparative examples were cut into a width of 50 mm and a length of 150 mm to prepare an evaluation sample.
In an environment of 100 ° C., the sample for evaluation was pressed against a sample area (width: 50 mm × length: 150 mm) with a load of 1 kg and left for 1 hour.
After leaving to cool at 23 ° C. for 1 hour, using a universal tensile tester (trade name “TG-1kN”, manufactured by Minebea), the separator was peeled off at a pulling speed of 300 mm / min and a peeling angle of 180 °. The peel force was measured. The measurement was performed in an environment of 23 ° C. × 50% RH.

[Shape of the release agent layer surface of the separator]
The shape of the surface of the release agent layer of the separator was observed using a confocal laser microscope (trade name “Scanning Laser Microscope LEXT-OLS3000”, manufactured by Olympus Corporation). The results are shown in FIGS. The measurement conditions are shown in Table 1 below.

The evaluation results are summarized in Table 2.

  From the said Table 2, in the case of the adhesive sheet which concerns on this invention (Examples 1-6), it became clear that it was excellent in the peelability of a separator in all the Examples, and the peeling voltage at the time of separator peeling was suppressed. On the other hand, in the case of the pressure-sensitive adhesive sheet using a separator having no unevenness on the surface of the release agent (Comparative Example 1), it can be seen that the peelability of the separator is inferior to that of the pressure-sensitive adhesive sheet obtained in the examples. It was. Moreover, in the adhesive sheet (Comparative Examples 2-5) which does not use an ionic liquid for an adhesive composition, peeling voltage was high and it was not able to prevent generation | occurrence | production of static electricity.

DESCRIPTION OF SYMBOLS 1 Separator base material 2 Water drop 3 Release agent layer 31 Release agent layer from which organic solvent evaporated 4 Release agent layer from which water droplet evaporated 5 Separator

Claims (8)

  After forming water droplets on at least one side of the separator base material on at least one side of the pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive composition containing a polymer having a glass transition temperature (Tg) of 0 ° C. or less as the ionic liquid and base polymer Then, an organic solvent solution containing a release agent is applied on the surface of the separator substrate on which water droplets are formed, and then the organic solvent and water droplets are removed, and the release agent is dried and / or cured to cause unevenness on the surface. A pressure-sensitive adhesive sheet in which a separator formed with a release agent layer having a shape is bonded so that the release agent layer having an uneven shape is on the pressure-sensitive adhesive layer side.   The pressure-sensitive adhesive sheet according to claim 1, wherein the method of forming water droplets is either a method of condensing the substrate surface by humidification or a method of spraying water.   The pressure-sensitive adhesive sheet according to claim 1 or 2, wherein the release agent is a thermosetting addition-type silicone release agent.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 3, wherein the ionic liquid is one or more selected from a nitrogen-containing onium salt, a sulfur-containing onium salt, or a phosphorus-containing onium salt. The pressure-sensitive adhesive sheet according to any one of claims 1 to 4, wherein the ionic liquid contains one or more selected from cations represented by the following formulas (A) to (D).
[In the formula (A), R ^a represents a hydrocarbon group having 4 to 20 carbon atoms and may contain a hetero atom, and R ^b and R ^c may be the same or different and each represents a hydrogen atom or a carbon number of 1 To 16 hydrocarbon groups, which may contain heteroatoms. However, when the nitrogen atom contains a double bond, there is no R ^c .
In the formula (B), R ^d represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a hetero atom, and R ^e , R ^f and R ^g may be the same or different and represent a hydrogen atom or a carbon atom. It represents a hydrocarbon group of formula 1 to 16, and may contain a hetero atom.
In the formula (C), R ^h represents a hydrocarbon group having 2 to 20 carbon atoms and may contain a hetero atom, and R ⁱ , R ^j and R ^k may be the same or different and represent a hydrogen atom or a carbon atom. It represents a hydrocarbon group of formula 1 to 16, and may contain a hetero atom.
In formula (D), Z represents a nitrogen, sulfur, or phosphorus atom, R ¹ , R ^m , R ⁿ , and R ^o are the same or different and each represents a hydrocarbon group having 1 to 20 carbon atoms; It may contain atoms. However, when Z is a sulfur atom, there is no R ^o ]   6. The polymer according to claim 1, wherein the polymer having a glass transition temperature (Tg) of 0 ° C. or lower is an acrylic polymer having a (meth) acrylate having a C 1-14 alkyl group as a main component. Adhesive sheet.   The pressure-sensitive adhesive sheet according to any one of claims 1 to 6, which is used as a surface protective film.   After forming water droplets on at least one side of the separator base material on at least one side of the pressure-sensitive adhesive layer comprising a pressure-sensitive adhesive composition containing a polymer having a glass transition temperature (Tg) of 0 ° C. or less as the ionic liquid and base polymer Then, an organic solvent solution containing a release agent is applied on the surface of the separator substrate on which water droplets are formed, and then the organic solvent and water droplets are removed, and the release agent is dried and / or cured to cause unevenness on the surface. A method for producing a pressure-sensitive adhesive sheet, comprising: bonding a separator formed with a release agent layer having a shape so that the release agent layer having a concavo-convex shape is on the pressure-sensitive adhesive layer side.