Pressure-sensitive adhesive details, optical films with pressure-sensitive adhesive details, display systems, display units, or methods for manufacturing display units.

Abstract

The invention relates to a pressure-sensitive adhesive component capable of enhancing the viewing capabilities of a virtual reality (VR) headset. The proposed pressure-sensitive adhesive component consists of: a pressure-sensitive adhesive layer; and a backing layer positioned on at least one side of the pressure-sensitive adhesive layer. The number of foreign particles on the surface of the pressure-sensitive adhesive layer is 12 or less within a 20 mm² area when the backing layer is peeled off the pressure-sensitive adhesive component in a Class 10000 cleanroom environment according to Federal Standard 209D. The pressure-sensitive adhesive component is used by being fitted onto a component to form a virtual reality (VR) headset.

Description

Adhesive member, optical film with adhesive member, display system, display body, and method for manufacturing display body

[0001] The present invention relates to a pressure-sensitive adhesive member, an optical film with a pressure-sensitive adhesive member, a display system, a display body, or a method for manufacturing a display body.

[0002] Image display devices, such as liquid crystal display devices and electroluminescence (EL) display devices (e.g., organic EL display devices), are rapidly becoming popular. In image display devices, optical components such as polarizing components and phase difference components are generally used to realize image display and improve image display performance (see, for example, Patent Document 1).

[0003] In recent years, new applications of image display devices have been developed. For example, goggles with displays (VR goggles) for realizing virtual reality (VR) have begun to be commercialized. Since the use of VR goggles in various situations is being considered, improvements in their visibility, etc. are desired.

[0004] Japanese Patent Application Laid-Open No. 2021-103286

[0005] A primary object of the present invention is to provide an adhesive member that can contribute to improving the visibility of VR goggles.

[0006] 1. A pressure-sensitive adhesive member according to an embodiment of the present invention comprises a pressure-sensitive adhesive layer and a release liner disposed on at least one side of the pressure-sensitive adhesive layer, wherein when the release liner is peeled from the pressure-sensitive adhesive member in a Class 10000 environment defined by Federal Standard 209D, the number of foreign particles on the surface of the pressure-sensitive adhesive layer is 12 or less within a 20 mm square area, and the pressure-sensitive adhesive member is used by being laminated to a component constituting VR goggles. 2. In the pressure-sensitive adhesive member described in 1 above, when the release liner is peeled from the pressure-sensitive adhesive member in an environment of a temperature of 23°C and a humidity of 55% Rh, the amount of charge on the surface of the pressure-sensitive adhesive layer may be less than 4.0 kV. 3. The pressure-sensitive adhesive member described in 1 or 2 above may further comprise a conductive layer, wherein the conductive layer, the pressure-sensitive adhesive layer, and the release liner are disposed in this order. 4. In the pressure-sensitive adhesive member described in any one of 1 to 3 above, the pressure-sensitive adhesive layer may contain an antistatic agent. 5 to 6. In the pressure-sensitive adhesive member according to any one of items 1 to 4 above, the release liner may contain an antistatic agent. 7. In the pressure-sensitive adhesive member according to item 3 above, the conductive layer may contain an antistatic agent. 8. In the pressure-sensitive adhesive member according to item 4 above, the antistatic agent may be an ionic liquid. 9. An optical film with a pressure-sensitive adhesive member according to an embodiment of the present invention comprises the pressure-sensitive adhesive member according to any one of items 1 to 8 above. 10. A display system according to an embodiment of the present invention is a display system that displays an image to a user, comprising: a display element having a display surface that emits light representing an image forward via a polarizing member; a reflecting section disposed in front of the display element and including a reflective polarizing member that reflects the light emitted from the display element; a first lens section disposed on an optical path between the display element and the reflecting section; a half mirror disposed between the display element and the first lens section that transmits the light emitted from the display element and reflects the light reflected by the reflecting section toward the reflecting section; a first λ / 4 member disposed on an optical path between the display element and the half mirror; and a second λ / 4 member disposed on an optical path between the half mirror and the reflecting section; and the adhesive-attached optical film described in 9. 11. In the display system described in 10, the display element may comprise the adhesive-attached optical film.12. A display according to an embodiment of the present invention comprises the display system described above in 10 or 11. 13. A method for manufacturing a display according to an embodiment of the present invention comprises the display system described above in 10 or 11. 14. The method for manufacturing a display according to 13 may include the operation of adhering the optical film with adhesive member described above in 9.

[0007] According to an embodiment of the present invention, an adhesive member that can contribute to improving the visibility of VR goggles can be provided.

[0008] Fig. 1 is a schematic cross-sectional view of an adhesive member according to an embodiment of the present invention. Fig. 2 is a schematic cross-sectional view of an adhesive member according to an embodiment of the present invention. Fig. 3 is a schematic view showing a schematic configuration of an example of a display system for VR goggles. Fig. 4 is a schematic cross-sectional view of an optical film with an adhesive member according to one embodiment of the present invention. Fig. 5 is a schematic cross-sectional view of a lens with an adhesive member according to one embodiment of the present invention.

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to these embodiments. In order to clarify the description, the drawings may schematically show the width, thickness, shape, etc. of each part compared to the embodiments, but these are merely examples and do not limit the interpretation of the present invention. Furthermore, duplicated descriptions of the drawings may be omitted.

[0010] (Definition of Terms and Symbols) The definitions of terms and symbols used in this specification are as follows. (1) Refractive Index (nx, ny, nz) "nx" is the refractive index in the direction in which the in-plane refractive index is maximum (i.e., the slow axis direction), "ny" is the refractive index in the in-plane direction perpendicular to the slow axis (i.e., the fast axis direction), and "nz" is the refractive index in the thickness direction. (2) In-Plane Retardation (Re) "Re(λ)" is the in-plane retardation measured with light having a wavelength of λ nm at 23°C. For example, "Re(550)" is the in-plane retardation measured with light having a wavelength of 550 nm at 23°C. Re(λ) is calculated by the formula: Re(λ) = (nx - ny) × d, where d (nm) is the thickness of the layer (film). (3) Thickness Direction Retardation (Rth) "Rth(λ)" is the retardation in the thickness direction measured with light having a wavelength of λ nm at 23°C. For example, "Rth(550)" is the retardation in the thickness direction measured with light having a wavelength of 550 nm at 23°C. Rth(λ) is calculated by the formula: Rth(λ) = (nx - nz) x d, where d (nm) is the thickness of the layer (film). (4) Nz coefficient The Nz coefficient is calculated by Nz = Rth / Re. (5) Angle When an angle is mentioned in this specification, the angle includes both clockwise and counterclockwise angles relative to the reference direction. Therefore, for example, "45°" means ±45°.

[0011] A. Adhesive Member Fig. 1 is a schematic cross-sectional view of an adhesive member according to an embodiment of the present invention. The adhesive member 100 according to the embodiment of the present invention comprises an adhesive layer 110 and a release liner 120 disposed on at least one surface of the adhesive layer 110.

[0012] 2 is a schematic cross-sectional view of a pressure-sensitive adhesive member according to another embodiment of the present invention. The pressure-sensitive adhesive member 100' according to this embodiment of the present invention comprises a conductive layer 130, a pressure-sensitive adhesive layer 110, and a release liner 120 in this order.

[0013] The adhesive member is used by being laminated on a component constituting the VR goggles. The adhesive member is used by being laminated directly on a component constituting the VR goggles.

[0014] In an embodiment of the present invention, when the release liner is peeled from the PSA member in a Class 10000 environment defined by Federal Standard 209D, the number of foreign particles on the surface of the PSA layer is 12 or less within a 20 mm square area. The release liner can be peeled at a peel angle of 180° and a pulling rate of 300 mm / min. The number of adhering foreign particles is measured using an optical microscope 5 minutes after the release liner is peeled, and foreign particles with a major axis of 10 μm or more can be counted.

[0015] In an embodiment of the present invention, by controlling the number of foreign particles as described above, an adhesive member can be provided that can prevent image display defects in VR goggles. In recent years, pancake lens systems and high-definition displays have been adopted for VR goggles, and image display defects caused by even smaller foreign particles can become a problem. In such cases, the adhesive member is particularly preferably used. Use of the adhesive member can prevent even the smallest foreign particles from getting mixed in, making it possible to provide a display system with significantly fewer image display defects.

[0016] In a Class 10000 environment defined by Federal Standard 209D, the number of foreign particles on the surface of the PSA layer when the release liner is peeled from the PSA member is preferably 10 or less, more preferably 8 or less, within a 20 mm square area. Within such a range, the above-mentioned effect becomes significant. The fewer the number of foreign particles, the better, and the lower limit is, for example, 5 (preferably 2, more preferably 0).

[0017] In a Class 10000 environment defined by Federal Standard 209D, when the release liner is peeled from the adhesive member, the number of foreign matter particles with a major axis of 20 μm or less on the surface of the adhesive layer within a 20 mm square area is preferably 6 or less, more preferably 5 or less, even more preferably 3 or less, and particularly preferably 0.

[0018] The number of foreign particles can be controlled, for example, by adjusting the amount of charge on the surface of the PSA layer when the release liner is peeled off. Under an environment of 23°C temperature and 55% Rh humidity, the amount of charge on the surface of the PSA layer when the release liner is peeled off is preferably less than 4.0 kV, more preferably less than 3.0 kV, even more preferably less than 2.0 kV, and particularly preferably less than 1.0 kV. The amount of charge is the amount of charge on the release surface of the release liner, and is measured 10 seconds after peeling the release liner at a peel angle of 180° and a pulling rate of 300 mm / min under an environment of 23°C temperature and 55% Rh humidity, at a distance of 35 mm from the PSA layer.

[0019] The amount of charge on the surface of the PSA layer when the release liner is peeled off can be adjusted by imparting a predetermined conductivity to one or more of the elements constituting the PSA member. For example, it can be adjusted by imparting conductivity to the PSA layer and / or the release liner. Alternatively, the amount of charge on the surface of the PSA layer may be adjusted by providing a conductive layer as shown in Figure 2. By providing a conductive layer, a PSA member can be constructed without imparting conductivity to the PSA layer, which makes it easier to control the adhesive properties.

[0020] In one embodiment, the amount of charge can be adjusted by adding an antistatic agent to the pressure-sensitive adhesive layer. According to this embodiment, a pressure-sensitive adhesive member with a simple structure can be obtained.

[0021] In one embodiment, the amount of charge can be adjusted by adding an antistatic agent to the release liner. According to this embodiment, a PSA member with a simple structure can be obtained. In addition, the PSA member can be constructed without imparting electrical conductivity to the PSA layer, which makes it easy to control the adhesive properties.

[0022] The adhesive strength at 23°C when the PSA member is attached to alkali-free glass is preferably 1.0 to 12.0 N / 25 mm, more preferably 2.0 to 10.0 N / 25 mm. In this specification, the adhesive strength refers to the adhesive strength of the PSA layer surface after the release liner has been peeled from the PSA member, measured by a method in accordance with JIS Z 0237:2009 (lamination conditions: one reciprocating stroke with a 2 kg roller, pulling speed: 300 mm / min, peel angle: 180°).

[0023] B. Pressure-sensitive adhesive layer The pressure-sensitive adhesive layer has a thickness of preferably 5 μm to 100 μm, more preferably 10 μm to 50 μm. From the viewpoint of smoothness, a thinner thickness is preferable.

[0024] The ISC value of the pressure-sensitive adhesive layer is, for example, 100 or less, preferably 50 or less. The ISC value can be an index of smoothness or unevenness. If the ISC value is within this range, a pressure-sensitive adhesive member that can realize a display system with excellent visibility can be obtained. The lower limit of the ISC value of the pressure-sensitive adhesive layer is, for example, 10. The ISC value can be calculated by measuring an image projected onto a screen through the pressure-sensitive adhesive layer using a CCD camera.

[0025] In one embodiment, the surface resistance value of the pressure-sensitive adhesive layer is preferably 1×10 １２ Ω / □, more preferably less than 5×10 １１ Ω / □, and more preferably less than 1×10 １０ Within this range, the pressure-sensitive adhesive layer can be made to have favorable electrical conductivity, and a pressure-sensitive adhesive member capable of preventing image display defects in VR goggles can be provided. The pressure-sensitive adhesive layer having electrical conductivity can be obtained, for example, by adding an antistatic agent described below. When forming a pressure-sensitive adhesive layer having electrical conductivity, the lower limit of the surface resistance value of the pressure-sensitive adhesive layer is, for example, 1 × 10 ８ The surface resistance is Ω / □. The method for measuring the surface resistance will be described later.

[0026] (Adhesive) The adhesive layer contains an adhesive. Examples of adhesives include rubber-based adhesives, acrylic-based adhesives, silicone-based adhesives, urethane-based adhesives, vinyl alkyl ether-based adhesives, polyvinylpyrrolidone-based adhesives, polyacrylamide-based adhesives, and cellulose-based adhesives. In one embodiment, an acrylic-based adhesive is used.

[0027] The acrylic pressure-sensitive adhesive contains a (meth)acrylic polymer as a base polymer, and the (meth)acrylic polymer contains structural units derived from alkyl (meth)acrylate.

[0028] Examples of alkyl(meth)acrylates include alkyl(meth)acrylates having a linear or branched alkyl group having 1 to 20 carbon atoms (more preferably 3 to 18, and particularly preferably 4 to 16). These can be used alone or in combination.

[0029] The content of the alkyl (meth)acrylate is preferably 65 to 99.99 parts by weight, and more preferably 70 to 99.9 parts by weight, based on 100 parts by weight of the (meth)acrylic polymer.

[0030] The (meth)acrylic polymer may contain, as necessary, a structural unit derived from another monomer (copolymerizable monomer) copolymerizable with the alkyl (meth)acrylate. Examples of such a monomer include the following monomers. Aromatic ring-containing monomers: phenoxyethyl (meth)acrylate, benzyl (meth)acrylate; carboxy group-containing monomers: for example, ethylenically unsaturated monocarboxylic acids such as acrylic acid (AA), methacrylic acid (MAA), crotonic acid, etc.; ethylenically unsaturated dicarboxylic acids such as maleic acid, itaconic acid, citraconic acid, etc., and their anhydrides (maleic anhydride, itaconic anhydride, etc.); hydroxyl group-containing monomers: for example, hydroxyalkyl (meth)acrylates such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, etc.; unsaturated alcohols such as vinyl alcohol, allyl alcohol, etc.; ether compounds such as 2-hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether, diethylene glycol monovinyl ether, etc.; amino group-containing monomers: for example, aminoethyl (meth)acrylate, N,N-dimethylaminoethyl (meth)acrylate, t-butylaminoethyl (meth)acrylate; Epoxy group-containing monomers: for example, glycidyl (meth)acrylate, methyl glycidyl (meth)acrylate, allyl glycidyl ether; cyano group-containing monomers: for example, acrylonitrile, methacrylonitrile; keto group-containing monomers: for example, diacetone (meth)acrylamide, diacetone (meth)acrylate, vinyl methyl ketone, vinyl ethyl ketone, allyl acetoacetate, vinyl acetoacetate; monomers having a nitrogen atom-containing ring: for example, N-vinyl-2-pyrrolidone, N-methylvinylpyrrolidone, N-vinylpyridine, N-vinylpiperidone, N-vinylpyrimidine, N-vinylpiperazine, N-vinylpyrazine, N-vinylpyrrole, N-vinylimidazole, N-vinyloxazole, N-vinylmorpholine, N-vinylcaprolactam, N-(meth)acryloylmorpholine;Alkoxysilyl group-containing monomers: for example, 3-(meth)acryloxypropyltrimethoxysilane, 3-(meth)acryloxypropyltriethoxysilane, 3-(meth)acryloxypropylmethyldimethoxysilane, 3-(meth)acryloxypropylmethyldiethoxysilane; Isocyanate group-containing monomers: (meth)acryloyl isocyanate, 2-(meth)acryloyloxyethyl isocyanate, m-isopropenyl-α,α-dimethylbenzyl isocyanate; Silane-based: 3-acryloxypropyltriethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10-acryloyloxydecyltriethoxysilane. These monomers may be used alone or in combination of two or more.

[0031] The content of the copolymerizable monomer is preferably 0.01 to 35 parts by weight, more preferably 2 to 25 parts by weight, based on 100 parts by weight of the (meth)acrylic polymer.

[0032] In one embodiment, the (meth)acrylic polymer contains a structural unit derived from a hydroxyl group-containing monomer and / or a structural unit derived from a carboxyl group-containing monomer. When the PSA contains a crosslinking agent, these copolymerizable monomers serve as reaction sites with the crosslinking agent. Hydroxyl group-containing monomers, carboxyl group-containing monomers, and the like are highly reactive with intermolecular crosslinking agents, and are therefore preferably used to improve the cohesiveness and heat resistance of the resulting PSA layer.

[0033] The weight-average molecular weight (Mw) of the (meth)acrylic polymer is, for example, 500,000 to 3,000,000, preferably 700,000 to 2,700,000, and more preferably 800,000 to 2,500,000. The weight-average molecular weight is measured by GPC (gel permeation chromatography) and calculated in terms of polystyrene.

[0034] The (meth)acrylic polymer can be produced by appropriately selecting a known production method such as solution polymerization, bulk polymerization, emulsion polymerization, various radical polymerizations, etc. The obtained (meth)acrylic polymer may be any of a random copolymer, a block copolymer, a graft copolymer, etc.

[0035] The PSA may contain any suitable additives as needed, such as crosslinking agents, crosslinking catalysts, tackifiers, plasticizers, pigments, dyes, fillers, antioxidants, conductive materials, antistatic agents, UV absorbers, light stabilizers, release modifiers, softeners, surfactants, flame retardants, and antioxidants.

[0036] The crosslinking agent may be an organic crosslinking agent or a polyfunctional metal chelate. Examples of organic crosslinking agents include isocyanate crosslinking agents, peroxide crosslinking agents, epoxy crosslinking agents, and imine crosslinking agents. Polyfunctional metal chelates are those in which a polyvalent metal is covalently or coordinately bonded to an organic compound. Examples of polyvalent metal atoms include Al, Cr, Zr, Co, Cu, Fe, Ni, V, Zn, In, Ca, Mg, Mn, Y, Ce, Sr, Ba, Mo, La, Sn, and Ti. Examples of atoms in the organic compound that form covalent or coordinate bonds include oxygen atoms, and examples of organic compounds include alkyl esters, alcohol compounds, carboxylic acid compounds, ether compounds, and ketone compounds.

[0037] The content of the crosslinking agent is preferably 3 parts by weight or less, more preferably 0.01 to 3 parts by weight, and even more preferably 0.02 to 2 parts by weight, relative to 100 parts by weight of the (meth)acrylic polymer.

[0038] (Antistatic Agent) As described above, in one embodiment, the pressure-sensitive adhesive layer contains an antistatic agent. As the antistatic agent, an ionic compound may be used, and preferably an ionic compound having a fluorine-containing anion is used. In addition, as the antistatic agent, an ionic surfactant, a conductive polymer, conductive fine particles, etc. may also be used. The pressure-sensitive adhesive layer containing the antistatic agent can be formed, for example, by applying a conductive pressure-sensitive adhesive composition containing the pressure-sensitive adhesive and the antistatic agent by any appropriate method.

[0039] Examples of the ionic compound include inorganic cation anion salts and organic cation anion salts.

[0040] The inorganic cation-anion salt may be, for example, an alkali metal salt formed from an alkali metal cation and an anion. The alkali metal salt may be an organic or inorganic salt of the alkali metal.

[0041] Examples of alkali metal ions that constitute the cation moiety of the alkali metal salt include lithium ions, sodium ions, and potassium ions, with lithium ions being preferred.

[0042] The anion moiety of the alkali metal salt may be composed of an organic substance or an inorganic substance. Examples of the anion moiety constituting the organic salt include CH ３ COO － , C.F. ３ COO － , C.H. ３ SO ３ － , C.F. ３ SO ３ － , (CF ３ SO ２ ) ３ C － , C ４ F ９ SO ３ － , C ３ F ７ COO － , (CF ３ SO ２ ) (CF ３ CO)N － , － O３ S (CF ２ ) ３ SO ３ － , P.F. ６ － , CO ３ ２－ , (C ｎ F ２ｎ＋１ SO ２ ) ２ N － (n is an integer from 1 to 10), CF ２ (C ｍ F ２ｍ SO ２ ) ２ N － (m is an integer from 1 to 10), － O ３ S (CF ２ ) ｌ SO ３ － (l is an integer from 1 to 10), (C ｐ F ２ｐ＋１ SO ２ ) N － (C ｑ F ２ｑ＋１ SO ２ ), (p and q are integers from 1 to 10), (FSO ２ ) ２ N － etc.

[0043] The anion moiety constituting the inorganic salt is Cl. － ,Br － , I － , AlCl ４ － , Al ２ Cl ７ － , B.F. ４ － , P.F. ６ － , ClO ４ － , NO ３ － , AsF ６ － , SbF ６ － , NbF ６ － , TaF ６ － , (CN)２ N － , etc. are used.

[0044] In one embodiment, an anion containing a fluorine atom is used. Alkali metal salts having an anion moiety containing a fluorine atom are advantageous in that they have excellent ion dissociation properties.

[0045] Examples of organic salts of alkali metals include sodium acetate, sodium alginate, sodium lignosulfonate, sodium toluenesulfonate, and LiCF ３ SO ３ , Li(CF ３ SO ２ ) ２ N, Li(CF ３ SO ２ ) ２ N, Li(C ２ F ５ SO ２ ) ２ N, Li(C ４ F ９ SO ２ ) ２ N, Li(CF ３ SO ２ ) ３ C, KO ３ S (CF ２ ) ３ SO ３ K, LiO ３ S (CF ２ ) ３ SO ３ Among these, LiCF ３ SO ３ , Li(CF ３ SO ２ ) ２ N, Li(C ２ F ５ SO ２ ) ２ N, Li(C ４ F ９ SO ２ ) ２ N, Li(CF ３ SO ２ ) ３ C, etc. are preferred, and Li(CF ３ SO ２ ) ２ N, Li(C ２F ５ SO ２ ) ２ N, Li(C ４ F ９ SO ２ ) ２ N, Li(FSO ２ ) ２ Fluorine-containing lithium imide salts such as N are more preferred, and bis(trifluoromethanesulfonyl)imide lithium salt and bis(fluorosulfonyl)imide lithium salt are particularly preferred.

[0046] Examples of inorganic salts of alkali metals include lithium perchlorate and lithium iodide.

[0047] The organic cation anion salt is an organic salt whose cation moiety is composed of an organic substance. The anion moiety may be an organic substance or an inorganic substance. The organic cation anion salt may be an ionic liquid or an ionic solid.

[0048] Preferably, an ionic liquid is used as the antistatic agent. The use of an ionic compound allows the formation of a pressure-sensitive adhesive layer with excellent transparency and smoothness. Forming such a pressure-sensitive adhesive layer allows the production of a pressure-sensitive adhesive member with few appearance defects. In this specification, the term "ionic liquid" refers to a molten salt (organic cation-anion salt) that is liquid at 40°C or less. Furthermore, it is particularly preferred that the ionic liquid have a melting point of 25°C or less.

[0049] The organic cation anion salt is composed of a cation component made of an organic substance and an anion component, and examples of the cation component include pyridinium cation, piperidinium cation, pyrrolidinium cation, cation having a pyrroline skeleton, cation having a pyrrole skeleton, imidazolium cation, tetrahydropyrimidinium cation, dihydropyrimidinium cation, pyrazolium cation, pyrazolinium cation, tetraalkylammonium cation, trialkylsulfonium cation, and tetraalkylphosphonium cation.

[0050] Examples of the anion component include 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 ) ３ C － , AsF ６ － , SbF ６ － , NbF ６ － , TaF ６ － , (CN) ２ N － , C ４ F ９ SO ３ － , C ３ F ７ COO － , ((CF ３ SO ２ )(CF ３ CO)N － , － O ３ S(CF<所给内容中此处似乎不完整,可能影响准确翻译,推测为类似括号等内容 ２ ) ３ SO ３ － , (C ｎ F ２ｎ＋１ SO[[ID=该部分内容似乎不完整,可能影响准确翻译 ２ )该部分内容似乎不完整,可能影响准确翻译 ２ N － (n is an integer from 1 to 10), CF ２ , (C ｍ F ２ｍ SO ２ ) ２ N －(m is an integer from 1 to 10), － O ３ S (CF ２ ) ｌ SO ３ － (l is an integer from 1 to 10), (C ｐ F ２ｐ＋１ SO ２ ) N － (C ｑ F ２ｑ＋１ SO ２ ), (p and q are integers from 1 to 10), (FSO ２ ) ２ N － etc.

[0051] In one embodiment, an anion containing a fluorine atom is used. Alkali metal salts having an anion moiety containing a fluorine atom are advantageous in that they have excellent ion dissociation properties.

[0052] In one embodiment, the anion containing a fluorine atom is preferably a fluorine-containing imide anion, and more preferably a bis(trifluoromethanesulfonyl)imide anion or a bis(fluorosulfonyl)imide anion. Of these, the bis(fluorosulfonyl)imide anion is preferred. The use of a bis(fluorosulfonyl)imide anion allows the desired charge amount to be achieved by adding a small amount. If the amount of antistatic agent added is small, the thickness of the pressure-sensitive adhesive layer can be reduced, thereby improving smoothness.

[0053] Furthermore, inorganic salts such as ammonium chloride, aluminum chloride, copper chloride, ferrous chloride, ferric chloride, and ammonium sulfate may also be used as the ionic compound.

[0054] Other antistatic agents that can be used include materials that can impart antistatic properties, such as ionic surfactants, conductive polymers, and conductive fine particles. Examples of ionic surfactants include cationic surfactants (e.g., quaternary ammonium salts, phosphonium salts, and sulfonium salts), anionic surfactants (e.g., carboxylic acid, sulfonate, sulfate, phosphate, and phosphite), amphoteric surfactants (e.g., sulfobetaine, alkylbetaine, and alkylimidazolium betaine), and nonionic surfactants (e.g., polyhydric alcohol derivatives, β-cyclodextrin inclusion compounds, sorbitan fatty acid monoesters and diesters, polyalkylene oxide derivatives, and amine oxides).

[0055] The content of the antistatic agent in the pressure-sensitive adhesive layer is preferably 0.05 to 20 parts by weight, more preferably 0.1 to 18 parts by weight, and even more preferably 1 to 16 parts by weight, relative to 100 parts by weight of the base polymer of the pressure-sensitive adhesive. Within such ranges, a pressure-sensitive adhesive layer excellent in transparency, durability, and adhesion can be formed.

[0056] C. Conductive Layer The surface resistance of the conductive layer is preferably 1×10 １２ Ω / □, more preferably less than 5×10 １１ Ω / □, and more preferably less than 1×10 １０ Within this range, it is possible to provide an adhesive member that can prevent defects in image display in VR goggles. The lower limit of the surface resistance value of the conductive layer is, for example, 1 × 10 ６ It is Ω / □.

[0057] Typically, the conductive layer contains an antistatic agent, which can adjust the conductivity of the conductive layer. Examples of the antistatic agent include the antistatic agents described above.

[0058] In one embodiment, the conductive layer comprises a conductive polymer, which is preferably used from the viewpoints of optical properties, appearance, antistatic effect, and stability under humid conditions.

[0059] Examples of conductive polymers include polyaniline and polythiophene. The conductive polymer may be soluble in an organic solvent, water-soluble, or water-dispersible. A water-soluble conductive polymer or a water-dispersible conductive polymer is preferably used.

[0060] Furthermore, the water-soluble conductive polymer or water-dispersible conductive polymer such as polyaniline or polythiophene preferably has a hydrophilic functional group in the molecule. Examples of the hydrophilic functional group include a sulfonic acid group, an amino group, an amide group, an imino group, a quaternary ammonium salt group, a hydroxyl group, a mercapto group, a hydrazino group, a carboxyl group, a sulfate ester group, a phosphate ester group, or salts thereof. By having a hydrophilic functional group in the molecule, the water-soluble conductive polymer or water-dispersible conductive polymer can be easily prepared.

[0061] In addition, a binder component can be added to the material for forming the anchor layer together with the conductive polymer for the purpose of improving the film-forming properties of the conductive polymer and its adhesion to the optical film. When the conductive polymer is a water-soluble or water-dispersible conductive polymer, a water-soluble or water-dispersible binder component is used. Examples of binders include oxazoline group-containing polymers, polyurethane resins, polyester resins, acrylic resins, polyether resins, cellulose resins, polyvinyl alcohol resins, epoxy resins, polyvinylpyrrolidone, polystyrene resins, polyethylene glycol, pentaerythritol, and the like. Polyurethane resins, polyester resins, and acrylic resins are particularly preferred. One or more of these binders can be used as appropriate depending on the application.

[0062] The amounts of the antistatic agent (preferably a conductive polymer) and binder used vary depending on their types, but are preferably adjusted so that the surface resistance of the resulting conductive layer falls within the above ranges.

[0063] D. Release Liner Examples of the release liner that can be used include release liners in which the surface of a substrate such as paper or plastic film is subjected to a release treatment such as silicone treatment or fluorosilicone treatment. Examples of the substrate include olefin-based resin films such as polyethylene-based resin films, polypropylene-based resin films, and cyclic olefin-based resin (COP) films, and polyester-based films such as polyethylene terephthalate-based films. Examples of the release liner that can be used include fluorine-based resin films such as polytetrafluoroethylene (PTFE)-based resin films, and olefin-based resin films such as polyethylene-based resin films, polypropylene-based resin films, and cyclic olefin-based resin (COP) films.

[0064] In one embodiment, the surface resistance of the release liner is preferably 1×10 １２ Ω / □, more preferably less than 5×10 １１ Ω / □, and more preferably less than 1×10 １０ The surface resistance of the release liner is preferably less than 1×10 Ω / □. By using a release liner having such electrical conductivity, it is possible to provide a PSA member that can prevent image display defects in VR goggles. When electrical conductivity is imparted to the release liner, the lower limit of the surface resistance of the release liner is, for example, 1×10 ６ It is Ω / □.

[0065] In one embodiment, the release liner has antistatic properties. Such a release liner contains, for example, an antistatic agent. The antistatic agent may be contained in the substrate (antistatic material-containing substrate) or the antistatic layer, which are components of the release liner. Examples of the antistatic agent include the antistatic agents described above. That is, the above-mentioned ionic compounds, ionic surfactants, conductive polymers, conductive fine particles, etc. may be used. In one embodiment, the release liner contains a conductive polymer. The amount of the antistatic agent (preferably a conductive polymer) used depends on the type of the antistatic agent, but it is preferably adjusted so that the surface resistance of the resulting release liner is within the above-mentioned range.

[0066] E. Display System FIG. 3 is a schematic diagram showing the overall configuration of a display system (VR goggles) according to one embodiment of the present invention. FIG. 3 schematically illustrates the arrangement and shape of each component of a display system 2. The display system 2 includes a display element 12, a reflector 14 including a reflective polarizing member, a first lens unit 16, a half mirror 18, a first phase difference member 20, a second phase difference member 22, and a second lens unit 24. The reflector 14 is disposed in front of the display surface 12a of the display element 12 and can reflect light emitted from the display element 12. The first lens unit 16 is disposed on the optical path between the display element 12 and the reflector 14, and the half mirror 18 is disposed between the display element 12 and the first lens unit 16. The first phase difference member 20 is disposed on the optical path between the display element 12 and the half mirror 18, and the second phase difference member 22 is disposed on the optical path between the half mirror 18 and the reflector 14.

[0067] The display element 12 is, for example, a liquid crystal display or an organic EL display, and has a display surface 12 a for displaying an image. The light emitted from the display surface 12 a passes through, for example, a polarizing member (typically, a polarizing film) that may be included in the display element 12, and is converted into first linearly polarized light.

[0068] The first phase difference member 20 is a λ / 4 member that can convert first linearly polarized light incident on the first phase difference member 20 into first circularly polarized light (hereinafter, the first phase difference member may be referred to as a first λ / 4 member). Note that the first phase difference member 20 may be provided integrally with the display element 12.

[0069] The half mirror 18 transmits light emitted from the display element 12 and reflects light reflected by the reflecting portion 14 toward the reflecting portion 14. The half mirror 18 is provided integrally with the first lens portion 16.

[0070] The second phase difference member 22 is a λ / 4 member that can transmit light reflected by the reflecting unit 14 and the half mirror 18 through the reflecting unit 14, which includes a reflective polarizing member (hereinafter, the second phase difference member may be referred to as a second λ / 4 member). Note that the second phase difference member 22 may be provided integrally with the first lens unit 16.

[0071] The first circularly polarized light emitted from the first λ / 4 member 20 passes through the half mirror 18 and the first lens unit 16, and is converted into the second linearly polarized light by the second λ / 4 member 22. The second linearly polarized light emitted from the second λ / 4 member 22 is reflected toward the half mirror 18 without passing through the reflective polarizing member included in the reflecting unit 14. At this time, the polarization direction of the second linearly polarized light incident on the reflective polarizing member included in the reflecting unit 14 is the same as the reflection axis of the reflective polarizing member. Therefore, the second linearly polarized light incident on the reflecting unit 14 is reflected by the reflective polarizing member.

[0072] The second linearly polarized light reflected by the reflecting unit 14 is converted into second circularly polarized light by the second λ / 4 member 22, and the second circularly polarized light emitted from the second λ / 4 member 22 passes through the first lens unit 16 and is reflected by the half mirror 18. The circularly polarized light reflected by the half mirror 18 passes through the first lens unit 16 and is converted into third linearly polarized light by the second λ / 4 member 22. The third linearly polarized light passes through the reflective polarizing member included in the reflecting unit 14. At this time, the polarization direction of the third linearly polarized light incident on the reflective polarizing member included in the reflecting unit 14 is the same direction as the transmission axis of the reflective polarizing member. Therefore, the third linearly polarized light incident on the reflecting unit 14 passes through the reflective polarizing member.

[0073] The light transmitted through the reflecting portion 14 passes through the second lens portion 24 and enters the user's eye 26 .

[0074] For example, the absorption axis of the polarizing member included in the display element 12 and the reflection axis of the reflective polarizing member included in the reflecting section 14 may be disposed approximately parallel to each other or approximately perpendicular to each other. The angle formed between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the first phase difference member 20 is, for example, 40° to 50°, may be 42° to 48°, or may be approximately 45°. The angle formed between the absorption axis of the polarizing member included in the display element 12 and the slow axis of the second phase difference member 22 is, for example, 40° to 50°, may be 42° to 48°, or may be approximately 45°.

[0075] The in-plane retardation Re(550) of the first retardation member 20 is, for example, 100 nm to 190 nm, may be 110 nm to 180 nm, may be 130 nm to 160 nm, or may be 135 nm to 155 nm.

[0076] The first phase difference member 20 preferably exhibits an inverse dispersion wavelength characteristic in which the phase difference value increases according to the wavelength of the measurement light. The Re(450) / Re(550) of the first phase difference member 20 is, for example, less than 1 and may be 0.95 or less, or may be less than 0.90, or may be 0.85 or less. The Re(450) / Re(550) of the first phase difference member 20 is, for example, 0.75 or more.

[0077] The first phase difference member 20 preferably has a refractive index characteristic that satisfies the relationship nx>ny≧nz. Here, "ny=nz" includes not only the case where ny and nz are completely equal, but also the case where they are substantially equal. Therefore, there may be cases where ny<nz, as long as the effects of the present invention are not impaired. The Nz coefficient of the first phase difference member 20 is preferably 0.9 to 3, more preferably 0.9 to 2.5, even more preferably 0.9 to 1.5, and particularly preferably 0.9 to 1.3.

[0078] The first retardation member 20 is formed of any appropriate material that can satisfy the above characteristics. The first retardation member 20 may be, for example, a stretched resin film or an oriented and solidified layer of a liquid crystal compound. Note that a stretched resin film may also be referred to as a retardation film.

[0079] Examples of resins contained in the resin film include polycarbonate-based resins, polyester carbonate-based resins, polyester-based resins, polyvinyl acetal-based resins, polyarylate-based resins, cyclic olefin-based resins, cellulose-based resins, polyvinyl alcohol-based resins, polyamide-based resins, polyimide-based resins, polyether-based resins, polystyrene-based resins, and acrylic-based resins. These resins may be used alone or in combination (e.g., blended or copolymerized). When the first phase difference member 20 exhibits reverse dispersion wavelength characteristics, a resin film containing a polycarbonate-based resin or a polyester carbonate-based resin (hereinafter sometimes simply referred to as a polycarbonate-based resin) can be suitably used.

[0080] As the polycarbonate-based resin, any suitable polycarbonate-based resin can be used as long as the effects of the present invention can be obtained. For example, the polycarbonate-based resin contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, and structural units derived from at least one dihydroxy compound selected from the group consisting of alicyclic diols, alicyclic dimethanols, di-, tri-, or polyethylene glycols, and alkylene glycols or spiroglycols. Preferably, the polycarbonate-based resin contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, structural units derived from an alicyclic dimethanol and / or structural units derived from di-, tri-, or polyethylene glycol; more preferably, it contains structural units derived from a fluorene-based dihydroxy compound, structural units derived from an isosorbide-based dihydroxy compound, and structural units derived from di-, tri-, or polyethylene glycol. The polycarbonate-based resin may contain structural units derived from other dihydroxy compounds as needed. Details of polycarbonate-based resins that can be suitably used for the first phase difference member and methods for forming the first phase difference member are described in, for example, JP 2014-10291 A, JP 2014-26266 A, JP 2015-212816 A, JP 2015-212817 A, and JP 2015-212818 A, and the descriptions in these publications are incorporated herein by reference.

[0081] The above-mentioned liquid crystal compound alignment solidified layer is a layer in which the liquid crystal compound is aligned in a predetermined direction within the layer and the alignment state is fixed. The term "alignment solidified layer" encompasses an alignment solidified layer obtained by curing a liquid crystal monomer, as described below. In the first retardation member, typically, rod-shaped liquid crystal compounds are aligned in the slow axis direction of the first retardation member (homogeneous alignment). Examples of rod-shaped liquid crystal compounds include liquid crystal polymers and liquid crystal monomers. The liquid crystal compound is preferably polymerizable. If the liquid crystal compound is polymerizable, the alignment state of the liquid crystal compound can be fixed by aligning the liquid crystal compound and then polymerizing it.

[0082] The alignment and solidification layer of the liquid crystal compound (liquid crystal alignment and solidification layer) can be formed by performing an alignment treatment on the surface of a predetermined substrate, applying a coating liquid containing a liquid crystal compound to the surface to align the liquid crystal compound in a direction corresponding to the alignment treatment, and fixing the alignment state. Any appropriate alignment treatment can be used as the alignment treatment. Specific examples include mechanical alignment treatment, physical alignment treatment, and chemical alignment treatment. Specific examples of mechanical alignment treatment include rubbing treatment and stretching treatment. Specific examples of physical alignment treatment include magnetic field alignment treatment and electric field alignment treatment. Specific examples of chemical alignment treatment include oblique vapor deposition and photoalignment treatment. Any appropriate treatment conditions can be used for the various alignment treatments depending on the purpose.

[0083] The alignment of liquid crystal compounds is achieved by treating them at a temperature at which they exhibit a liquid crystal phase depending on the type of liquid crystal compound. By performing such temperature treatment, the liquid crystal compounds assume a liquid crystal state and are aligned in accordance with the alignment treatment direction on the substrate surface.

[0084] In one embodiment, the alignment state is fixed by cooling the liquid crystal compound aligned as described above. When the liquid crystal compound is polymerizable or crosslinkable, the alignment state is fixed by subjecting the liquid crystal compound aligned as described above to a polymerization treatment or a crosslinking treatment.

[0085] Any suitable liquid crystal polymer and / or liquid crystal monomer can be used as the liquid crystal compound. The liquid crystal polymer and the liquid crystal monomer can be used alone or in combination. Specific examples of liquid crystal compounds and methods for producing a liquid crystal alignment solidified layer are described in, for example, JP 2006-163343 A, JP 2006-178389 A, and WO 2018 / 123551 A. The descriptions in these publications are incorporated herein by reference.

[0086] The thickness of the first retardation member 20 is preferably 100 μm or less. Specifically, the thickness of the first retardation member 20 made of a stretched resin film is, for example, 10 μm to 100 μm, preferably 10 μm to 70 μm, more preferably 10 μm to 60 μm, and even more preferably 20 μm to 50 μm. The thickness of the first retardation member 20 made of a liquid crystal alignment solidified layer is, for example, 1 μm to 10 μm, preferably 1 μm to 8 μm, more preferably 1 μm to 6 μm, and even more preferably 1 μm to 4 μm.

[0087] The in-plane retardation Re(550) of the second retardation member 22 is, for example, 100 nm to 190 nm, may be 110 nm to 180 nm, may be 130 nm to 160 nm, or may be 135 nm to 155 nm.

[0088] The second phase difference member 22 preferably exhibits an inverse dispersion wavelength characteristic in which the phase difference value increases according to the wavelength of the measurement light. The Re(450) / Re(550) of the second phase difference member 22 is, for example, less than 1 and may be 0.95 or less, or even less than 0.90, or even 0.85 or less. The Re(450) / Re(550) of the second phase difference member 22 is, for example, 0.75 or more.

[0089] The second phase difference member 22 preferably has a refractive index characteristic that satisfies the relationship nx>ny≧nz. Here, "ny=nz" includes not only the case where ny and nz are completely equal, but also the case where they are substantially equal. Therefore, there may be cases where ny<nz, as long as the effects of the present invention are not impaired. The Nz coefficient of the second phase difference member 22 is preferably 0.9 to 3, more preferably 0.9 to 2.5, even more preferably 0.9 to 1.5, and particularly preferably 0.9 to 1.3.

[0090] The second retardation member 22 is formed of any appropriate material that can satisfy the above characteristics. The second retardation member 22 may be, for example, a stretched resin film or a layer of oriented and solidified liquid crystal compounds. The same explanation as for the first retardation member 20 can be applied to the second retardation member 22 that is formed of a stretched resin film or a layer of oriented and solidified liquid crystal compounds. The first retardation member 20 and the second retardation member 22 may be members having the same configuration (forming material, thickness, optical properties, etc.) or may be members having different configurations.

[0091] The thickness of the second retardation member 22 is preferably 100 μm or less. Specifically, the thickness of the second retardation member 22 made of a stretched resin film is, for example, 10 μm to 100 μm, preferably 10 μm to 70 μm, more preferably 10 μm to 60 μm, and even more preferably 20 μm to 50 μm. The thickness of the second retardation member 22 made of a liquid crystal alignment solidified layer is, for example, 1 μm to 10 μm, preferably 1 μm to 8 μm, more preferably 1 μm to 6 μm, and even more preferably 1 μm to 4 μm.

[0092] The reflective section 14 may include an absorptive polarizing element in addition to a reflective polarizing element. The absorptive polarizing element may be disposed in front of the reflective polarizing element. The reflection axis of the reflective polarizing element and the absorption axis of the absorptive polarizing element may be disposed approximately parallel to each other, and the transmission axis of the reflective polarizing element and the transmission axis of the absorptive polarizing element may be disposed approximately parallel to each other. When the reflective section 14 includes an absorptive polarizing element, the reflective section 14 may include a laminate having a reflective polarizing element and an absorptive polarizing element.

[0093] The reflective polarizing element can transmit light polarized parallel to its transmission axis (typically, linearly polarized light) while maintaining its polarization state, and reflect light polarized in other states. The orthogonal transmittance (Tc) of the reflective polarizing element can be, for example, 0.01% to 3%. The single transmittance (Ts) of the reflective polarizing element can be, for example, 43% to 49%, preferably 45% to 47%. The polarization degree (P) of the reflective polarizing element can be, for example, 92% to 99.99%. The reflective polarizing element is typically composed of a film having a multilayer structure (sometimes referred to as a reflective polarizing film). Commercially available reflective polarizing films include, for example, "DBEF" and "APF" manufactured by 3M, and "APCF" manufactured by Nitto Denko Corporation.

[0094] The absorptive polarizing member may typically include a resin film (sometimes referred to as an absorptive polarizing film) containing a dichroic material. The thickness of the absorptive polarizing film is, for example, 1 μm or more and 20 μm or less, or may be 2 μm or more and 15 μm or less, 12 μm or less, 10 μm or less, 8 μm or less, or 5 μm or less.

[0095] The absorptive polarizing film may be made from a single layer of resin film or may be made from a laminate of two or more layers.

[0096] When the absorptive polarizing film is produced from a single-layer resin film, for example, an absorptive polarizing film can be obtained by subjecting a hydrophilic polymer film such as a polyvinyl alcohol (PVA)-based film, a partially formalized PVA-based film, or a partially saponified ethylene-vinyl acetate copolymer-based film to a dyeing treatment with iodine or a dichroic substance such as a dichroic dye, a stretching treatment, etc. Among these, an absorptive polarizing film obtained by dyeing a PVA-based film with iodine and uniaxially stretching it is preferred.

[0097] The dyeing with iodine is carried out, for example, by immersing the PVA-based film in an aqueous iodine solution. The stretching ratio of the uniaxial stretching is preferably 3 to 7 times. The stretching may be carried out after the dyeing treatment or while dyeing. Alternatively, the PVA-based film may be dyed after stretching. If necessary, the PVA-based film may be subjected to a swelling treatment, a crosslinking treatment, a washing treatment, a drying treatment, or the like.

[0098] Examples of laminates produced using the two or more layer laminate include a laminate of a resin substrate and a PVA-based resin layer (PVA-based resin film) laminated on the resin substrate, and a laminate of a resin substrate and a PVA-based resin layer formed by coating on the resin substrate. An absorptive polarizing film obtained using a laminate of a resin substrate and a PVA-based resin layer formed by coating on the resin substrate can be produced, for example, by applying a PVA-based resin solution to the resin substrate and drying the solution to form a PVA-based resin layer on the resin substrate, thereby obtaining a laminate of the resin substrate and the PVA-based resin layer, and then stretching and dyeing the laminate to convert the PVA-based resin layer into an absorptive polarizing film. In this embodiment, a polyvinyl alcohol-based resin layer containing a halide and a polyvinyl alcohol-based resin is preferably formed on one side of the resin substrate. The stretching typically involves immersing the laminate in an aqueous boric acid solution to stretch it. Furthermore, the stretching may further include in-air stretching of the laminate at a high temperature (e.g., 95°C or higher) before stretching in the boric acid aqueous solution, as necessary. In addition, in this embodiment, the laminate is preferably subjected to a drying shrinkage treatment in which the laminate is heated while being transported in the longitudinal direction, thereby shrinking the laminate by 2% or more in the width direction. Typically, the manufacturing method of this embodiment includes subjecting the laminate to an auxiliary in-air stretching treatment, a dyeing treatment, an underwater stretching treatment, and a drying shrinkage treatment, in this order. By introducing auxiliary stretching, it is possible to increase the crystallinity of the PVA, even when the PVA is coated on a thermoplastic resin, thereby achieving high optical properties. Furthermore, by simultaneously increasing the orientation of the PVA in advance, problems such as a decrease in orientation or dissolution of the PVA when immersed in water in the subsequent dyeing or stretching steps can be prevented, thereby achieving high optical properties. Furthermore, when the PVA-based resin layer is immersed in a liquid, the disordering of the polyvinyl alcohol molecules and the decrease in orientation can be suppressed compared to when the PVA-based resin layer does not contain a halide. This can improve the optical properties of the absorptive polarizing film obtained through treatment steps in which the laminate is immersed in a liquid, such as a dyeing treatment and an underwater stretching treatment.Furthermore, the optical properties can be improved by shrinking the laminate in the width direction through a drying shrinkage treatment.The obtained resin substrate / absorptive polarizing film laminate may be used as is (i.e., the resin substrate may be used as a protective layer for the absorptive polarizing film), or any suitable protective layer may be laminated depending on the purpose on the surface obtained by peeling the resin substrate from the resin substrate / absorptive polarizing film laminate or on the surface opposite to the peeled surface. Details of such methods for producing an absorptive polarizing film are described in, for example, JP-A-2012-73580 and Japanese Patent No. 6,470,455. The entire disclosures of these publications are incorporated herein by reference.

[0099] The crossed transmittance (Tc) of the absorptive polarizing element (absorptive polarizing film) is preferably 0.5% or less, more preferably 0.1% or less, and even more preferably 0.05% or less. The single transmittance (Ts) of the absorptive polarizing element (absorptive polarizing film) is, for example, 41.0% to 45.0%, and preferably 42.0% or more. The polarization degree (P) of the absorptive polarizing element (absorptive polarizing film) is, for example, 99.0% to 99.997%, and preferably 99.9% or more.

[0100] The elements included in the display unit having the display system are integrated together via adhesive layers as needed, which may be formed of an adhesive or a pressure-sensitive adhesive.

[0101] In one embodiment, any one of the adhesive layers is the pressure-sensitive adhesive layer described in Section B, or a laminate including the pressure-sensitive adhesive layer and the conductive layer described in Section C.

[0102] 4 is a schematic cross-sectional view of an optical film with a pressure-sensitive adhesive according to one embodiment of the present invention. The optical film with a pressure-sensitive adhesive 200 comprises an optical film A and the pressure-sensitive adhesive 100 arranged on at least one side of the optical film A. The pressure-sensitive adhesive 100 can be arranged so that the release liner 120 is on the opposite side to the optical film A. The pressure-sensitive adhesive may be an adhesive having a conductive layer (i.e., the pressure-sensitive adhesive 100' shown in FIG. 2).

[0103] Any appropriate optical film can be used as the optical film A. Examples of the optical film A include a reflective polarizer, an absorptive polarizer, a reflective polarizing plate, an absorptive polarizing plate, and a retardation film. Examples of the reflective polarizing plate include the reflective polarizing member described above. Examples of the absorptive polarizing plate include the absorptive polarizing member described above. Examples of the retardation film include the first retardation member and the second retardation member described above. The optical film may be a single layer or a multilayer. In one embodiment, the outermost layer of the optical film on the pressure-sensitive adhesive member side is made of a low-moisture-permeable material. Examples of low-moisture-permeable materials include cycloolefin-based resins and polycarbonate-based resins. When the pressure-sensitive adhesive member includes a pressure-sensitive adhesive layer containing an ionic liquid (e.g., an ionic liquid composed of an anion containing a fluorine atom, such as a bis(fluorosulfonyl)imide anion), if the outermost layer of the optical film on the pressure-sensitive adhesive member side is made of a low-moisture-permeable material, penetration of the ionic liquid into the optical film can be suppressed. The moisture permeability of the low moisture permeable material at 40°C x 92% RH is, for example, 10 g / (m ２ ・24h)~900g / (m ２ The moisture permeability can be measured in accordance with the moisture permeability test (cup method) of JIS Z 0208.

[0104] In the manufacture of a display having a display system, a release liner is peeled from an optical film with a pressure-sensitive adhesive member, and an optical film with a pressure-sensitive adhesive layer is attached. In this embodiment, a display with a pressure-sensitive adhesive layer is provided. By using the pressure-sensitive adhesive member according to the embodiment of the present invention, the optical film can be attached while preventing the inclusion of foreign matter. This is particularly advantageous in that it can prevent the inclusion of even minute foreign matter.

[0105] In one embodiment, there is provided an optical film with a pressure-sensitive adhesive member, which includes an optical film including an absorptive polarizing member and the above-mentioned pressure-sensitive adhesive member. This optical film with a pressure-sensitive adhesive member can be preferably used as a polarizing member in the above-mentioned display element, for example, by peeling off the release liner. In this embodiment, there can be provided a display element with a pressure-sensitive adhesive layer. The optical film including the absorptive polarizing member may further include a retardation film.

[0106] 5 is a schematic cross-sectional view of a lens with an adhesive member according to one embodiment of the present invention. The lens with an adhesive member 300 comprises a lens B and an adhesive member 100 arranged on at least one side of the lens B. In this embodiment, a lens with an adhesive layer may be provided. The adhesive member 100 may be arranged so that the release liner 120 is on the opposite side to the lens B. The adhesive member may be an adhesive member with a conductive layer (i.e., the adhesive member 100' shown in FIG. 2). Examples of the lens B include the second lens portion and the first lens portion.

[0107] The present invention will be specifically explained below with reference to examples, but the present invention is not limited to these examples.

[0108] [Production Example 1] (Preparation of Absorptive Polarizing Film) A long roll of a 30 μm-thick polyvinyl alcohol (PVA) resin film (manufactured by Kuraray Co., Ltd., product name "PE3000") was uniaxially stretched in the longitudinal direction to 5.9 times its original length using a roll stretching machine, while simultaneously undergoing swelling, dyeing, crosslinking, and washing treatments, and finally drying treatment to produce an absorptive polarizing film with a thickness of 12 μm. Specifically, the swelling treatment involved stretching the film 2.2 times while treating it with pure water at 20°C. Next, the dyeing treatment involved stretching the film 1.4 times while treating it in an aqueous solution at 30°C containing iodine and potassium iodide in a weight ratio of 1:7, the iodine concentration of which was adjusted, so that the resulting absorptive polarizing film had a single transmittance of 45.0%. Furthermore, the crosslinking treatment was a two-stage process, with the first stage involving stretching the film 1.2 times while treating it in an aqueous solution at 40°C containing boric acid and potassium iodide dissolved therein. The aqueous solution used in the first crosslinking treatment had a boric acid content of 5.0 wt % and a potassium iodide content of 3.0 wt %. The second crosslinking treatment involved stretching the film 1.6 times while treating it in an aqueous solution containing boric acid and potassium iodide dissolved at 65°C. The aqueous solution used in the second crosslinking treatment had a boric acid content of 4.3 wt % and a potassium iodide content of 5.0 wt %. The cleaning treatment involved treating it with an aqueous potassium iodide solution at 20°C. The aqueous solution used in the cleaning treatment had a potassium iodide content of 2.6 wt %. Finally, the film was dried at 70°C for 5 minutes to obtain an absorptive polarizing film. (Fabrication of Polarizing Member) A hydroxylated triacetylcellulose (TAC)-based resin film (TAC thickness: 25 μm, HC thickness: 7 μm) was laminated to one side of the obtained absorptive polarizing film as a protective layer, and a cycloolefin-based resin film (thickness: 13 μm) was laminated to the other side. Specifically, the curable adhesive was applied to a total thickness of approximately 1 μm, and the films were laminated using a roller. The adhesive was then cured by irradiating it with UV light from the TAC film side. This resulted in a polarizing element having a structure of [TAC film (protective layer) / absorptive polarizing film / COP film (protective layer)].

[0109] [Production Example 2] (Formation of Pressure-Sensitive Adhesive Layer) A monomer mixture containing 94.9 parts by weight of butyl acrylate, 5 parts by weight of acrylic acid, and 0.1 parts by weight of 2-hydroxyethyl acrylate was charged into a four-neck flask equipped with a stirring blade, a thermometer, a nitrogen gas inlet tube, and a condenser. Furthermore, 0.3 parts by weight of dibenzoyl peroxide as a polymerization initiator was charged together with ethyl acetate per 100 parts by weight of this monomer mixture. Nitrogen gas was introduced into the flask with gentle stirring to replace the atmosphere with nitrogen, and the liquid temperature in the flask was maintained at 60°C to carry out a polymerization reaction for 7 hours. Ethyl acetate was then added to the resulting reaction solution to adjust the solids concentration to 30% by weight, thereby preparing a solution of an acrylic polymer having a weight-average molecular weight (Mw) of 2,200,000. An acrylic pressure-sensitive adhesive was prepared by blending 0.6 parts by weight of a trimethylolpropane / tolylene diisocyanate adduct (trade name: Coronate L, manufactured by Tosoh Corporation) and 0.075 parts by weight of a silane coupling agent (trade name: KBM403, manufactured by Shin-Etsu Chemical Co., Ltd.) with 100 parts by weight of the solids content of the obtained acrylic polymer solution. The obtained acrylic pressure-sensitive adhesive was coated on a substrate film, and the resulting coating film on the substrate film was dried in an oven to form a pressure-sensitive adhesive layer with a thickness of 15 μm.

[0110] [Example 1] (Preparation of conductive adhesive composition) A four-neck flask equipped with a stirring blade, a thermometer, a nitrogen gas inlet tube, and a condenser was charged with a monomer mixture containing 75 parts by weight of butyl acrylate (BA), 21 parts by weight of phenoxyethyl acrylate (PEA), 3.3 parts by weight of N-vinyl-2-pyrrolidone (NVP), 0.3 parts by weight of acrylic acid (AA), and 0.4 parts by weight of 4-hydroxybutyl acrylate (HBA). Furthermore, 0.1 parts by weight of 2,2'-azobisisobutyronitrile as a polymerization initiator was charged together with 100 parts by weight of ethyl acetate per 100 parts by weight of the monomer mixture (solid content). Nitrogen gas was introduced while gently stirring to replace the atmosphere with nitrogen, and the liquid temperature in the flask was maintained at around 55°C, whereby a polymerization reaction was carried out for 8 hours to prepare an acrylic polymer liquid. The acrylic polymer liquid (solid content 100 parts by weight) obtained above was blended with 5 parts by weight of an ionic compound (organic cation anion salt (ionic liquid), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.), 0.2 parts by weight of an isocyanate crosslinking agent (Mitsui Chemicals, Inc., Takenate D160N, trimethylolpropane hexamethylene diisocyanate), 0.3 parts by weight of benzoyl peroxide (NOF Corporation, Niper BMT), and a silane coupling agent (Shin-Etsu Chemical Co., Ltd.: X-41-1810) to prepare a conductive adhesive composition containing an adhesive and an antistatic agent. (Preparation of Adhesive Member) The conductive adhesive composition was applied to a release liner (manufactured by Mitsubishi Chemical Polyester Film Corporation, product name "MRF38") to obtain an adhesive member consisting of a release liner and a conductive adhesive layer (thickness: 20 μm). (Preparation of Optical Film) An optical film with a pressure-sensitive adhesive was obtained by laminating the above-mentioned pressure-sensitive adhesive on the polarizing member obtained in Production Example 1 so that the COP film of the polarizing member faced the conductive pressure-sensitive adhesive layer. A schematic diagram of the structure of the obtained optical film with a pressure-sensitive adhesive is shown in Table 1, along with schematic diagrams of the structures of Examples 2 to 5 and Comparative Example (adhesive layer not shown).

[0111]

[0112] [Example 2] An optical film with a pressure-sensitive adhesive member was obtained in the same manner as in Example 1, except that the amount of the ionic compound (organic cation anion salt (ionic liquid), 1-ethyl-3-methylimidazolium bis(fluorosulfonyl)imide, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) was changed to 0.5 parts by weight.

[0113] Example 3 (Preparation of Conductive Layer-Forming Composition) 8.6 parts by weight of a thiophene-based polymer solution (trade name: Denatron P-580W, manufactured by Nagase ChemteX Corporation), 1 part by weight of a solution containing an oxazoline group-containing acrylic polymer (trade name: EPOCROS WS-700, manufactured by Nippon Shokubai Co., Ltd.), and 90.4 parts by weight of water were mixed to prepare a conductive layer-forming composition with a solids concentration of 0.5 wt%. The resulting conductive layer-forming composition contained 0.04 wt% of a polythiophene-based polymer and 0.25 wt% of an oxazoline group-containing acrylic polymer. (Conductive Layer Formation) The conductive layer-forming composition was applied to the COP film side of the polarizing element to a dry thickness of 50 nm and dried at 80°C for 2 minutes to form a conductive layer. The resulting conductive layer contained 8 wt% of the thiophene-based polymer and 50 wt% of the oxazoline group-containing acrylic polymer, respectively. (Preparation of Pressure-Sensitive Adhesive Member) The conductive layer was laminated on a release liner (manufactured by Mitsubishi Chemical Polyester Film Corporation, product name "MRF38") via the pressure-sensitive adhesive layer obtained in Production Example 2, to obtain a pressure-sensitive adhesive member consisting of a release liner, a pressure-sensitive adhesive layer, and a conductive layer. (Preparation of Optical Film) The pressure-sensitive adhesive member was laminated on the polarizing member obtained in Production Example 1, with the COP film and the conductive layer of the polarizing member facing each other, to obtain an optical film with a pressure-sensitive adhesive member (polarizing member / pressure-sensitive adhesive member (conductive layer / pressure-sensitive adhesive layer / release liner)).

[0114] [Example 4] (Preparation of adhesive member) The adhesive layer obtained in Production Example 2 was laminated on a conductive release liner (manufactured by Mitsubishi Chemical Polyester Film Corporation, product name "MRQ75") to obtain an adhesive member consisting of a conductive release liner and an adhesive layer (thickness: 15 μm). (Preparation of optical film) The above adhesive member was laminated on the polarizing member obtained in Production Example 1 so that the COP film and adhesive layer of the polarizing member faced each other, to obtain an optical film with an adhesive member.

[0115] [Example 5] (Preparation of conductive layer) A conductive layer was obtained in the same manner as in Example 3. (Preparation of adhesive member) The conductive layer was laminated onto a conductive release liner (manufactured by Mitsubishi Chemical Polyester Film Corporation, product name "MRQ75") via the adhesive layer obtained in Production Example 2, to obtain an adhesive member consisting of a conductive release liner, an adhesive layer (thickness: 15 μm), and a conductive layer. (Preparation of optical film) The adhesive member was laminated onto the polarizing member obtained in Production Example 1 so that the COP film and the conductive layer of the polarizing member faced each other, to obtain an optical film with an adhesive member.

[0116] [Comparative Example 1] (Preparation of adhesive member) The adhesive layer obtained in Production Example 2 was laminated on a release liner (manufactured by Mitsubishi Chemical Polyester Film Corporation, product name "MRF38") to obtain an adhesive member consisting of a release liner and an adhesive layer (thickness: 15 μm). (Preparation of optical film) The above adhesive member was laminated on the polarizing member obtained in Production Example 1 so that the COP film and adhesive layer of the polarizing member faced each other, to obtain an optical film with an adhesive member.

[0117] <Foreign matter adhesion> The release liners were peeled from the optical films with pressure-sensitive adhesive members obtained in the Examples and Comparative Examples, and observed with an optical microscope (20x magnification) to measure the number and size of foreign matter in a 20 mm x 20 mm area. If the total number of foreign matter observed (total number of foreign matter having a size of 10 μm or more) was 10 or more, it was rated as × (fail), if it was 5 to 9, it was rated as ○ (pass (preferable)), and if it was 4 or less, it was rated as ⊚ (pass (more preferable). The release liner was peeled at a peel angle of 180° and a pulling speed of 300 mm / min. The number of foreign matter adhesions was measured 5 minutes after the release liner was peeled off.

[0118] <Surface Resistivity> The surface resistance of the element to which conductivity was imparted (the pressure-sensitive adhesive layer in Comparative Example 1) was measured using MCP-HT450 manufactured by Mitsubishi Chemical Analytech Co., Ltd. The surface resistance was measured for 10 seconds at an applied voltage of 250 V (Examples 1 and 2) or 10 V (Examples 3 to 5, Comparative Example 1).

[0119] <Charge Amount> The release liner was peeled off from the optical film with pressure-sensitive adhesive member obtained in the Examples and Comparative Examples, and the charge amount of the pressure-sensitive adhesive layer and the conductive pressure-sensitive adhesive layer was measured 10 seconds after peeling. The measurement environment was 23°C and 55% RH. The peeling conditions were a peel angle of 180° and a pulling speed of 300 mm / min. The charge amount was measured using a Statilon DZ4 manufactured by Shishido Electrostatic Corporation, at a distance of 35 mm from the surface of the pressure-sensitive adhesive layer (the surface where the release liner was laminated).

[0120] <Smoothness> Using EyeScale-4W manufactured by I-Systems, the level of in-plane unevenness (smoothness) of the adhesive layer was calculated as the ISC value in the ISC measurement mode of the 3CCD image sensor based on the specifications of the device. (Measurement conditions) The adhesive layer was attached to an alkali-free glass plate (Corning, 1737) and used as a sample. The light source, sample, and screen were installed in this order, and the transmitted image of the sample projected onto the screen was measured using a CCD camera. The distance from the light source and CCD camera to the sample (adhesive layer attached to the alkali-free glass plate) was 30 cm. The distance from the light source and CCD camera to the screen was also 100 cm. The light source and CCD camera were installed 20 cm apart so that the distance from the sample and the screen was the same. The ISC value is related to the evaluation of unevenness, and if the ISC value is 100 or less, it can be determined that unevenness has been reduced. The smaller the ISC value, the less unevenness is judged to be present. An ISC value of 50 to 100 was rated as ◯ (preferable), and 50 or less was rated as ⊚ (more preferable).

[0121] The results are shown in Table 2.

[0122] As is clear from Table 2, according to the embodiment of the present invention, it is possible to provide a PSA member that has little adhesion of foreign matter when the release liner is peeled off. An optical film including the PSA member (an optical film with a PSA member) can be attached to a component constituting a VR goggle (for example, a display panel) with the PSA layer serving as an adhesion surface. By using a PSA member that has little adhesion of foreign matter, it is possible to obtain VR goggles that are prevented from having display defects.

[0123] The adhesive member according to the embodiment of the present invention can be used in a display such as VR goggles, for example.

[0124] 2 Display system 12 Display element 14 Reflection section 16 First lens section 18 Half mirror 20 First phase difference member 22 Second phase difference member 24 Second lens section 100, 100' Adhesive member 110 Adhesive layer 120 Release liner 130 Conductive layer

Claims

1. An adhesive material comprising an adhesive layer and a release liner disposed on at least one side of the adhesive layer, wherein when the release liner is peeled off from the adhesive material in a Class 10,000 environment as stipulated in Federal Standard 209D, the number of foreign objects on the surface of the adhesive layer is 12 or less within a 20 mm square area, said adhesive material being used by laminating it to a component constituting VR goggles.

2. The adhesive member according to claim 1, wherein the amount of charge on the surface of the adhesive layer when the release liner is peeled off in an environment of a temperature of 23° C. and a humidity of 55% Rh is less than 4.0 kV.

3. The adhesive member according to claim 1, further comprising a conductive layer, the conductive layer, the adhesive layer, and the release liner being arranged in this order.

4. The adhesive member according to claim 1, wherein the adhesive layer contains an antistatic agent.

5. The adhesive member according to claim 1, wherein the release liner contains an antistatic agent.

6. The adhesive member according to claim 3, wherein the release liner contains an antistatic agent.

7. The adhesive member according to claim 3, wherein the conductive layer contains an antistatic agent.

8. The adhesive member according to claim 4, wherein the antistatic agent is an ionic liquid.

9. An optical film with an adhesive member comprising the adhesive member according to any one of claims 1 to 8.

10. A display system for displaying an image to a user, comprising: a display element having a display surface which emits light representing an image forward via a polarizing member; a reflecting section arranged in front of the display element, which includes a reflective polarizing member and reflects the light emitted from the display element; a first lens section arranged on an optical path between the display element and the reflecting section; a half mirror arranged between the display element and the first lens section, which transmits the light emitted from the display element and reflects the light reflected by the reflecting section towards the reflecting section; a first λ / 4 member arranged on the optical path between the display element and the half mirror; and a second λ / 4 member arranged on the optical path between the half mirror and the reflecting section; and the display system comprises an optical film with adhesive member according to claim 9.

11. The display system according to claim 10, wherein the display element comprises the optical film with the adhesive member.

12. A display comprising the display system according to claim 10.

13. A method for manufacturing a display comprising the display system according to claim 10.

14. A method for manufacturing a display as claimed in claim 13, comprising the step of adhering the optical film with adhesive member as claimed in claim 9.

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