Laminate, bonded body, and image display system

Abstract

An object of the present invention is to provide a laminate capable of suppressing generation of bubble-like defects even in a case where a foreign substance is present between an adhesive layer and an object to be bonded, a bonded body using the laminate, and an image display system using the laminate.SOLUTION: The laminate has a reflection layer and an adhesive layer, and the thickness of the adhesive layer is larger than 100 μm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a laminate having a reflective layer and an adhesive layer, a bonded body obtained by bonding this laminate to an object to be bonded, and an image display system using this laminate. [Background technology]

[0002] Currently, there is known a head-up display or head-up display system that projects an image onto the windshield of a vehicle or the like to provide the driver with various information such as a map, driving speed, and vehicle status.

[0003] In a head-up display system, a virtual image containing the above-mentioned various pieces of information is projected onto the windshield glass and is observed by the driver, etc. The virtual image is formed at a position outside the vehicle forward of the windshield glass. The position where the virtual image is formed is usually more than 1000 mm forward from the windshield glass, closer to the outside world than the windshield glass. This allows the driver to obtain the above-mentioned various pieces of information while looking at the outside world in front of them without having to move their line of sight significantly. Therefore, when using a head-up display system, it is expected that drivers will be able to drive more safely while obtaining various pieces of information.

[0004] A head-up display system is constructed by attaching a light-transmitting reflective film, such as a half-mirror film, to a windshield glass to form a display portion for projected images. Various types of such reflective films have been proposed.

[0005] For example, Patent Document 1 proposes an optical film that can be used as a display medium in a head-up display system, the optical film having an optical functional layer and a blocking layer, the blocking layer having a cured product of a resin composition containing a thermoplastic resin and an ultraviolet-curable resin. In this optical film, examples of the optical functional layer include a half-wave plate, a quarter-wave plate, a laminate of a half-wave plate and a circularly polarized light reflective layer, and a laminate of a quarter-wave plate and a circularly polarized light reflective layer, etc. Furthermore, an example of the circularly polarized light reflective layer is a light reflective layer using a cholesteric liquid crystal. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] International Publication No. 2021 / 039394 Summary of the Invention [Problem to be solved by the invention]

[0007] As shown in Patent Document 1, a reflective film used in a head-up display system is used by being attached to glass such as a windshield glass. As a method for laminating a sheet-like material such as a reflective film onto an object such as a windshield glass, a method utilizing thermocompression bonding using an adhesive layer, conceptually shown in FIG. 6, is known.

[0008] In this method, first, as shown in the upper part of Figure 6, a laminate 100 such as a reflective film laminated with an adhesive layer (not shown) is sandwiched between an object to be bonded 102 having a curved surface such as a windshield glass and a mold 104 having a curved surface similar to that of the object to be bonded 102, and is placed in a bag 106 such as a rubber bag as shown in the second part of Figure 6. Next, the bag 106 is heated while being depressurized, so that the laminate 100 (adhesive layer) is vacuum-heat-pressurized to the object 102 to be attached. After the pressure bonding using the bag 106 is completed, the laminated body obtained by bonding the laminated body 100 to the object to be bonded 102 is removed from the bag, and as shown in the third row of Figure 6, the laminated body is heated and pressed using an autoclave, and then the laminated body 100 is heated and pressed to the object to be bonded 102. After the heat-pressing process using the autoclave is completed, the laminated body is removed from the autoclave, and the mold 104 is removed, as shown in the lower part of Figure 6, to obtain a laminated body in which the laminated body 100 is bonded to the object to be bonded 102.

[0009] According to this method for producing a bonded body, a laminate such as a reflective film having an adhesive layer can be bonded along the surface of an object to be bonded, such as a glass plate. On the other hand, the thickness of the block layer in Patent Document 1 is 50 μm or less. Therefore, in this manufacturing method of a bonded body, if foreign matter such as dust adhering to the adhesive layer and / or the surface of the bonded object is large compared to the adhesive layer, and the bonded object is then bonded with the foreign matter sandwiched between the adhesive layer and the bonded object, a portion of the adhesive layer will be raised from the bonded object due to the foreign matter. Such a portion of the adhesive layer raised from the bonded object will become a bubble-like defect, causing problems such as reduced visibility of the projected image in a head-up display system. Therefore, there is a demand for a laminate that can produce a laminate with few bubble-like defects even when large foreign matter is present between the object to be laminated and the adhesive layer.

[0010] The object of the present invention is to solve the problems of the conventional technology and to provide a laminate that can suppress the occurrence of bubble-like defects caused by foreign matter even if foreign matter is present between the adhesive layer and the object to be bonded, a bonded body using this laminate, and an image display system using this laminate. [Means for solving the problem]

[0011] The present inventors have found that the occurrence of the bubble-like defects can be suppressed by using a laminate having a reflective layer and an adhesive layer with a thickness of more than 100 μm, preferably by subjecting the laminate to autoclaving. Specifically, the inventors have found that the above object can be achieved by the following configuration.

[0012] [1] A laminate having a reflective layer and an adhesive layer, the thickness of the adhesive layer being greater than 100 μm. [2] The laminate according to [1], further comprising a retardation layer. [3] The laminate according to [1] or [2], further comprising a polarization conversion layer. [4] The laminate according to any one of [1] to [3], further comprising a hard coat layer. [5] The laminate according to any one of [1] to [4], which comprises a hard coat layer, a reflective layer, a retardation layer, a polarization conversion layer, and an adhesive layer. [6] A laminate comprising glass and the laminate according to any one of [1] to [5] attached to the glass. [7] A laminate comprising a polycarbonate layer and the laminate according to any one of [1] to [5] attached to the polycarbonate layer. [8] A laminate comprising a windshield glass and the laminate according to any one of [1] to [5] attached to the windshield glass. [9] An image display system comprising the laminate according to any one of [1] to [5] and an image display device that projects an image onto the laminate. [Effects of the Invention]

[0013] According to the present invention, it is possible to provide a laminate that can be laminated to an object while suppressing the occurrence of bubble defects after lamination. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a diagram conceptually illustrating an example of a laminate of the present invention. [Figure 2] 1 is a conceptual diagram for explaining a method for producing a bonded body of the present invention. [Figure 3] 1 is a conceptual diagram for explaining a method for producing a bonded body of the present invention. [Figure 4] FIG. 1 is a diagram conceptually illustrating an example of an image display system of the present invention. [Figure 5] FIG. 5 is a partially enlarged view of FIG. [Figure 6] FIG. 1 is a conceptual diagram for explaining a conventional method for manufacturing a bonded body. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE INVENTION The laminate, bonded body, and image display system of the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings. The drawings described below are conceptual diagrams for explaining the present invention, and the present invention is not limited to these diagrams. Therefore, the size, shape, and positional relationship of each component, as well as the thickness of each layer in the laminate and the thickness relationship between each layer, may differ from the actual ones. In the following description, the symbol "to" indicating a numerical range includes the values ​​written on both sides. For example, if ε1 is between α1 and β1, the range of ε1 includes α1 and β1, and expressed in mathematical notation, α1≦ε1≦β1.

[0016] The laminate of the present invention has a reflective layer and an adhesive layer. FIG. 1 conceptually shows an example of the laminate of the present invention. The illustrated laminate 10 has, from the bottom in the figure, a protective film 12, a hard coat layer 14, a transparent resin layer 16, a retardation layer 18, a reflective layer 20, a polarization conversion layer 24, and an adhesive layer 26.

[0017] In the laminate 10 shown in FIG. 1, the protective film 12, the hard coat layer 14, the transparent resin layer 16, the retardation layer 18, and the polarization conversion layer 24 are provided as a preferred embodiment. Therefore, the laminate of the present invention is not limited to one having all of these layers, and these layers may be appropriately selected and used depending on the application of the laminate, etc. Alternatively, the laminate of the present invention may have, in addition to these layers, various known layers (films, membranes) used in optical films (optical elements), such as a polarizer, a refractive index matching layer, an interference layer, and a filter. That is, the laminate of the present invention can have various layer configurations as long as it has a reflective layer and an adhesive layer with a thickness of more than 100 μm. Among these, a configuration having one layer selected from a hard coat layer, a retardation layer, and a polarization conversion layer in addition to a reflective layer and an adhesive layer is preferred, a configuration having multiple layers is more preferred, and a configuration having all of these is even more preferred.

[0018] (reflective layer) The laminate 10 of the present invention has a reflective layer 20 . The reflective layer 20 reflects part or all of visible light, and is not particularly limited. Examples of the reflective layer 20 include a layer containing a metal, a layer in which a dielectric is laminated, and a layer containing a liquid crystal. The reflective layer 20 preferably includes a cholesteric liquid crystal layer having a selective reflection center wavelength in the red wavelength region, a cholesteric liquid crystal layer having a selective reflection center wavelength in the green wavelength region, and a cholesteric liquid crystal layer having a selective reflection center wavelength in the blue wavelength region. The three cholesteric liquid crystal layers have different selective reflection center wavelengths. Each cholesteric liquid crystal layer may be in direct contact with any of the other cholesteric liquid crystal layers.

[0019] As is well known, a cholesteric liquid crystal layer is a layer in which liquid crystal compounds are fixed in a helical oriented state of a cholesteric liquid crystal phase, and reflects light with a selective reflection center wavelength corresponding to the pitch of the helical structure and transmits light in other wavelength ranges. Furthermore, a cholesteric liquid crystal layer exhibits selective reflection for either left- or right-handed circularly polarized light at a specific wavelength.

[0020] Here, from the viewpoint of visibility, it is preferable that the reflective layer 20 satisfy the following requirements (i) to (iii). (i) In the wavelength range of 400 nm or more and less than 500 nm, the maximum value of natural light reflectance is more than 7% (preferably more than 20%), the difference between the maximum and minimum values ​​of natural light reflectance is 3% or more, and the total value of the wavelength bandwidth of the region higher than the average value of the maximum and minimum values ​​of natural light reflectance is 20 to 80 nm. (ii) In the wavelength range of 500 nm or more and less than 600 nm, the maximum value of natural light reflectance is more than 7% (preferably more than 20%), the difference between the maximum and minimum values ​​of natural light reflectance is 3% or more, and the total value of the wavelength bandwidth of the region higher than the average value of the maximum and minimum values ​​of natural light reflectance is 20 to 80 nm. (iii) In the wavelength range of 600 to 800 nm, the maximum value of the natural light reflectance is more than 7% (preferably 20% or more), and the total value of the wavelength bandwidth of the region higher than the average value of the maximum and minimum values ​​of the natural light reflectance is 120 nm or more.

[0021] In a reflective layer having a cholesteric liquid crystal layer, the reflected wavelength and reflectance can be adjusted by the selective reflection center wavelength and thickness (helical pitch number) of the cholesteric liquid crystal layer. Reflection that satisfies requirement (i) can be achieved mainly by a cholesteric liquid crystal layer that reflects light in the blue wavelength region, reflection that satisfies requirement (ii) can be achieved by a cholesteric liquid crystal layer that reflects light in the green wavelength region, and reflection that satisfies requirement (iii) can be achieved by a cholesteric liquid crystal layer that reflects light in the red wavelength region.

[0022] From the viewpoint of improving the reflected color and increasing the transmittance, the maximum value of the natural light reflectance at 400 nm or more and less than 500 nm is preferably more than 7%, more preferably 20% or more. There is no particular upper limit, but it is often 35% or less, for example. Similarly, from the viewpoint of improving the reflected color and increasing the transmittance, the maximum natural light reflectance at 500 nm or more and less than 600 nm is preferably more than 7%, more preferably 20% or more. There is no particular upper limit, but it is often 35% or less, for example. From the viewpoint of improving the reflective color and increasing the brightness of the displayed image, the maximum natural light reflectance in the range of 600 to 800 nm is preferably more than 7%, more preferably 20% or more. There is no particular upper limit, but it is often 35% or less, for example.

[0023] From the viewpoint of increasing the transmittance while improving the reflected color, the difference between the maximum and minimum values ​​of the natural light reflectance at 400 nm or more and less than 500 nm is preferably 4 to 20%, more preferably 4 to 12%. Similarly, from the viewpoint of being able to increase transmittance while improving the reflected color, the difference between the maximum and minimum values ​​of natural light reflectance at 500 nm or more and less than 600 nm is preferably 4 to 20%, more preferably 4 to 12%.

[0024] From the viewpoint of improving the reflected color while increasing the transmittance, the wavelength bandwidth of the region in which the reflectance is higher than the average value of the maximum and minimum reflectance values ​​in the range of 400 nm or more and less than 500 nm is preferably 30 to 78 nm, more preferably 35 to 75 nm. Similarly, from the viewpoint of improving the reflected color while increasing the transmittance, the wavelength bandwidth of the region in which the reflectance is higher than the average value of the maximum and minimum reflectance values ​​from 500 nm or more to less than 600 nm is preferably 30 to 78 nm, and more preferably 35 to 75 nm. The narrower the wavelength bandwidth from 400 nm to less than 500 nm and from 500 nm to less than 600 nm, the better the transmittance, but since the wavelength bandwidth from 600 to 800 nm is wide, if the wavelength bandwidth from 400 nm to less than 500 nm and / or the wavelength bandwidth from 500 nm to less than 600 nm is too narrow, the reflected color may deteriorate. From this point of view, it is preferable that the wavelength bandwidth from 400 nm to less than 500 nm and the wavelength bandwidth from 500 nm to less than 600 nm are within the above ranges. Furthermore, the wavelength band width between 500 nm and less than 600 nm has a greater effect on the transmittance.

[0025] From the viewpoint of improving the reflected color and the front brightness of the displayed image, the wavelength bandwidth of the region where the reflectance is higher than the average of the maximum and minimum values ​​of the reflectance in the range of 600 to 800 nm is preferably 120 to 200 nm.

[0026] The reflective layer 20 preferably has two or more cholesteric liquid crystal layers with different selective reflection center wavelengths, and each cholesteric liquid crystal layer is preferably in direct contact with any other cholesteric liquid crystal layer.

[0027] If the cholesteric liquid crystal layers are spaced apart, the thickness between the layers becomes thicker, making it difficult to obtain the effect of interference of light reflected by each cholesteric liquid crystal layer. In contrast, a configuration in which the cholesteric liquid crystal layers are in contact with each other is preferable because the wavelength bandwidth can be narrowed by the effect of interference of light reflected by each cholesteric liquid crystal layer. In particular, if the thickness of each cholesteric liquid crystal layer is thinner than the wavelength of light (visible light 380 to 780 nm), the effect of interference becomes more pronounced, which is preferable.

[0028] When the reflective layer 20 has two or more cholesteric liquid crystal layers, the cholesteric liquid crystal layers are not limited to being in direct contact with each other, and may be stacked with an adhesive layer or the like interposed therebetween.

[0029] Here, each cholesteric liquid crystal layer may have at least one selective reflection center wavelength, but at least one of the cholesteric liquid crystal layers may have two or more selective reflection center wavelengths. A cholesteric liquid crystal layer having two or more selective reflection center wavelengths is achieved by a helical structure in which the helical pitch changes in the thickness direction.

[0030] The total thickness of the reflective layer 20 is preferably 0.4 to 2.0 μm, more preferably 0.6 to 1.8 μm, and even more preferably 0.8 to 1.4 μm.

[0031] (adhesive layer) As mentioned above, the laminate 10 of the present invention includes the adhesive layer 26 along with the reflective layer 20 . The adhesive layer 26 is a layer for physically joining (sticking) the laminate and the object to be pasted. Here, in the laminate 10 of the present invention, the adhesive layer 26 has a thickness greater than 100 μm. Having the above thickness, the laminate 10 of the present invention can suitably embed (embed) foreign matter, and air around the defect dissolves in the adhesive layer, eliminating air bubbles. As a result, the laminate 10 of the present invention can prevent the adhesive layer around the foreign matter from being raised due to the foreign matter, which would otherwise be visually recognized as a bubble-like defect. This point will be discussed in more detail later.

[0032] The adhesive layer 26 is not particularly limited in material as long as it has transparency that ensures visibility of the display content when attached to an object to be pasted and can bond the laminate 10 to the object to be pasted. Therefore, the adhesive layer 26 may be made of a resin or an elastomer (including oil-extended rubber). The adhesive layer 26 is preferably a layer that is plasticized by heat when attached to an object to be attached and exhibits adhesive properties (heat seal layer).

[0033] In the laminate 10 of the present invention, the adhesive layer 26 may be formed by direct application to the laminate 10 (polarization conversion layer 24 in the illustrated example), or may be prepared separately from the laminate 10 and adhered to the laminate 10, or when adhering the laminate 10 to an object to be attached, such as glass, the adhesive layer 26 prepared separately from the laminate 10 may be sandwiched between the laminate 10 and the object to be attached and heated and pressed together, for example.

[0034] The adhesive layer 26 preferably comprises a thermoplastic resin or an elastomer. Thermoplastic resins that have good affinity and adhesion with the substrate (e.g., glass substrate) are preferred, and examples thereof include polyolefin resins such as 1,2-polybutadiene resin, ethylene-vinyl acetate copolymer (abbreviated as "EVA," which usually contains 3% by mass or more of vinyl acetate structural units), polyethylene, polyvinyl chloride resin, polystyrene resin, vinyl ester resin (excluding EVA), saturated polyester resin, polyamide resin, fluororesin (e.g., polyvinylidene fluoride), polycarbonate resin, polyacetal resin, urethane resin, epoxy resin, (meth)acrylate resin (also called (meth)acrylic resin, meaning (meth)acrylic acid ester resin, etc.), unsaturated polyester resin, silicone resin, and modified resins of these resins. Urethane resins include urethane-modified polyester resin and urethane resin. Preferred examples of thermoplastic resins include (meth)acrylate resins, polyvinyl butyral, and ethylene-vinyl acetate copolymers from the viewpoint of adhesiveness (non-peelability) of the adhesive layer 26 in the laminate 10, and urethane resins and polyolefin resins from the viewpoint of impact resistance.

[0035] Polyvinyl butyral can be obtained by acetalizing polyvinyl alcohol with butyraldehyde. The degree of acetalization of polyvinyl butyral is not particularly limited, but is preferably 40% or more, more preferably 60% or more. The upper limit is not particularly limited, but is preferably 85% or less, more preferably 75% or less. Polyvinyl alcohol used in the synthesis of polyvinyl butyral is usually obtained by saponifying polyvinyl acetate, and polyvinyl alcohol with a saponification degree of 80 to 99.8 mol % is generally used. The degree of polymerization of the polyvinyl alcohol is preferably 200 to 3,000.

[0036] Examples of elastomers include conjugated diene block (co)polymers, acrylic block (co)polymers, styrene block (co)polymers, block copolymers of aromatic vinyl compounds and conjugated dienes, hydrogenated products of conjugated diene block (co)polymers, hydrogenated products of block copolymers of aromatic vinyl compounds and conjugated dienes, ethylene-α-olefin copolymers, polar group-modified olefin copolymers, elastomers composed of polar group-modified olefin copolymers and metal ions and / or metal compounds, nitrile rubbers such as acrylonitrile-butadiene rubber, butyl rubber, acrylic rubber, thermoplastic elastomers such as thermoplastic polyolefin elastomers (TPO), thermoplastic polyurethane elastomers (TPU), thermoplastic polyester elastomers (TPEE), thermoplastic polyamide elastomers (TPAE), diene elastomers (1,2-polybutadiene, etc.), silicone elastomers, and fluorine-based elastomers.

[0037] The thermoplastic resin or elastomer may be synthesized by a known method, or a commercially available product may be used. Examples of commercially available elastomers include Kuralyte LA1114, Kuralyte LA2140, Kuralyte LA2250, Kuralyte LA2330, Kuralyte LA4285, Hybrar 5127, Hybrar 7311F, Septon 2104, and Septon 2063 (trade names, manufactured by Kuraray Co., Ltd.). As the elastomer, an acrylic block (co)polymer or a styrene block (co)polymer is preferred from the viewpoint of oxygen solubility.

[0038] The weight average molecular weight of the thermoplastic resin and elastomer is preferably 10,000 to 1,000,000, more preferably 50,000 to 500,000, from the viewpoint of the balance between solubility in a solvent and storage modulus.

[0039] From the viewpoints of scratch resistance and slipperiness with respect to the substrate such as glass, the storage modulus E' of the adhesive layer 26 at 25°C and a frequency of 1 Hz is preferably 1 MPa or more. The storage modulus E' is more preferably 10 MPa or more, and even more preferably 100 MPa or more. There is no particular upper limit to the storage modulus E', but it is generally 10 GPa or less.

[0040] The maximum value of the loss tangent (tanδ) of the adhesive layer 26 at a frequency of 1 Hz is preferably in the temperature range of −40° C. to 120° C., more preferably −20 to 120° C. By setting tanδ within the above range, the adhesive layer can be softened by thermocompression bonding and can be bonded to the object to be pasted.

[0041] In the present invention, the storage modulus of the adhesive layer 26 at 25° C. and a frequency of 1 Hz and tan δ at a frequency of 1 Hz are determined as follows.

[0042] (Sample preparation method) The adhesive layer is dissolved in a solvent or melted, and the resulting coating solution is applied to the release-treated surface of a release-treated PET (polyethylene terephthalate) sheet so that the thickness after drying is 40 μm. After drying, the adhesive layer is peeled off from the release PET sheet to prepare a test piece of the adhesive layer. (Measurement method) Using a dynamic viscoelasticity measuring device (DVA-225, manufactured by ITS Japan Co., Ltd.), measurements are carried out under the following conditions on the above test specimens, which have been previously conditioned for at least 2 hours at a temperature of 25°C and a relative humidity of 60%, to obtain the temperature dependence of tan δ, storage modulus, and loss modulus at a frequency of 1 Hz. Sample: 5mm x 20mm Grip distance: 20 mm Setting distortion: 0.10% Frequency: 1Hz Measurement temperature: -60~140℃ Temperature increase condition: 2℃ / min

[0043] The adhesive layer 26 is preferably formed using a composition (adhesive layer-forming composition) containing a polymerizable compound for chemically bonding to adjacent layers in the laminate (the polarization conversion layer 24 in the illustrated example, or the reflective layer 20 if the reflective layer 20 is adjacent). The polymerizable compound is preferably one that can chemically bond to a polymerizable liquid crystal compound used to form an adjacent layer in the laminate; for example, if the polymerizable liquid crystal compound has an ethylenically unsaturated polymerizable group, the polymerizable compound also preferably has an ethylenically unsaturated polymerizable group.

[0044] Examples of the ethylenically unsaturated polymerizable group-containing compound include the following: However, the present invention is not limited to the following exemplary compounds. For example, polyethylene glycol 200 di(meth)acrylate, polyethylene glycol 300 di(meth)acrylate, polyethylene glycol 400 di(meth)acrylate, polyethylene glycol 600 di(meth)acrylate, triethylene glycol di(meth)acrylate, epichlorohydrin-modified ethylene glycol di(meth)acrylate (commercially available products include Denacol DA-811 manufactured by Nagase & Co., Ltd.), polypropylene glycol 200 di(meth)acrylate, polypropylene glycol 400 di(meth)acrylate, polypropylene glycol 700 di(meth)acrylate, ethylene oxide (EO)·propylene oxide (PO)Propylene oxide) block polyether di(meth)acrylate (commercially available products, such as the Blenmer PET series manufactured by Nippon Oil & Fats Co., Ltd.), dipropylene glycol di(meth)acrylate, bisphenol A EO adduct di(meth)acrylate (commercially available products, such as M-210 manufactured by Toagosei Co., Ltd. and NK Ester A-BPE-20 manufactured by Shin-Nakamura Chemical Co., Ltd.), hydrogenated bisphenol A EO adduct di(meth)acrylate (NK Ester A-HPE-4 manufactured by Shin-Nakamura Chemical Co., Ltd.), bisphenol A PO adduct di(meth)acrylate (commercially available products, such as Light Acrylate BP-4PA manufactured by Kyoeisha Chemical Co., Ltd.), bisphenol A epichlorohydrin adduct di(meth)acrylate (commercially available products, such as Ebecryl 150 manufactured by Daicel UCB Co., Ltd.), bisphenol A EO·PO addition type di(meth)acrylate (commercially available products include BP-023-PE manufactured by Toho Chemical Industry Co., Ltd.), bisphenol F Examples of bifunctional (meth)acrylate compounds include EO-added di(meth)acrylate (commercially available products include, for example, Aronix M-208 manufactured by Toagosei Co., Ltd.), 1,6-hexanediol di(meth)acrylate and its epichlorohydrin-modified products, neopentyl glycol di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate and its caprolactone-modified products, 1,4-butanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, trimethylolpropane di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, pentaerythritol di(meth)acrylate monostearate, trimethylolpropane acrylic acid benzoate, and isocyanuric acid EO-modified di(meth)acrylate (commercially available products include, for example, Aronix M-215 manufactured by Toagosei Co., Ltd.);

[0045] Furthermore, trifunctional (meth)acrylate compounds such as trimethylolpropane tri(meth)acrylate (commercially available products include, for example, TPMTA manufactured by Nippon Kayaku Co., Ltd.) and its EO, PO, or epichlorohydrin-modified products, pentaerythritol tri(meth)acrylate, glycerol tri(meth)acrylate and its EO, PO, or epichlorohydrin-modified products, isocyanuric acid EO-modified tri(meth)acrylate (commercially available products include, for example, Aronix M-315 manufactured by Toagosei Co., Ltd.), tris(meth)acryloyloxyethyl phosphate, hydrogen phthalate-(2,2,2-tri-(meth)acryloyloxymethyl)ethyl, glycerol tri(meth)acrylate and its EO, PO, or epichlorohydrin-modified products; Examples of such compounds include tetrafunctional (meth)acrylate compounds such as dipentaerythritol tetra(meth)acrylate (commercially available products include TPMTA manufactured by Shin-Nakamura Chemical Co., Ltd.) and its EO, PO, or epichlorohydrin-modified products, and ditrimethylolpropane tetra(meth)acrylate; pentafunctional (meth)acrylate compounds such as dipentaerythritol penta(meth)acrylate and its EO, PO, epichlorohydrin, fatty acid, or alkyl-modified products; and hexafunctional (meth)acrylate compounds such as dipentaerythritol hexa(meth)acrylate and its EO, PO, epichlorohydrin, fatty acid, or alkyl-modified products, and sorbitol hexa(meth)acrylate and its EO, PO, epichlorohydrin, fatty acid, or alkyl-modified products. Two or more ethylenically unsaturated polymerizable group-containing compounds may be used in combination. In this case, a mixture of dipentaerythritol pentaacrylate and dipentaerythritol hexaacrylate, "DPHA" (manufactured by Nippon Kayaku Co., Ltd.), can be preferably used.

[0046] Preferred ethylenically unsaturated polymerizable group-containing compounds include polyester (meth)acrylates and epoxy (meth)acrylates having a weight-average molecular weight of 200 or more but less than 1,000. Commercially available polyester (meth)acrylates include the Beamset 700 series manufactured by Arakawa Chemical Industries, Ltd., such as Beamset 700 (hexafunctional), Beamset 710 (tetrafunctional), and Beamset 720 (trifunctional). Epoxy (meth)acrylates include the SP series manufactured by Showa Polymer Co., Ltd., such as SP-1506, 500, SP-1507, and 480, and the VR series, such as VR-77, as well as EA-1010 / ECA, EA-11020, EA-1025, and EA-6310 / ECA manufactured by Shin-Nakamura Chemical Co., Ltd.

[0047] The I / O ratio (ratio of inorganic value (I value) to organic value (O value)) of the polymerizable compound (particularly, an ethylenically unsaturated polymerizable group-containing compound) is preferably 0.40 or more, more preferably 0.60 or more, and even more preferably 1.2 or more, from the viewpoint of adhesion to adjacent layers in a laminate. There is no particular upper limit to the I / O ratio, but from the viewpoint of compatibility with thermoplastic resins, it is preferably less than 3.0.

[0048] The I / O ratio is calculated using the calculation method of the organic conceptual diagram. The organic conceptual diagram was proposed by Fujita et al. and is an effective method for predicting various physicochemical properties from the chemical structure of an organic compound (see Koda Yoshio, Organic Conceptual Diagram - Basics and Applications, Sankyo Publishing, 1984). Since the polarity of an organic compound is influenced by the number of carbon atoms and substituents, the inorganic and organic values ​​of other substituents are determined based on the organic value of the methylene group being 20 and the inorganic value of the hydroxyl group being 100, and then the inorganic and organic values ​​of the organic compound are calculated. Organic compounds with a high inorganic value have high polarity, and organic compounds with a high organic value have low polarity.

[0049] Specific methods for calculating the above I value, O value, and I / O ratio have been published as an Excel organic concept diagram calculation sheet (http: / / www.ecosci.jp / sheet / orgs_help.html) by Homma et al., co-authors of "New Edition Organic Concept Diagram: Fundamentals and Applications," and these can be used for calculations.

[0050] When the composition used to form the adhesive layer 26 contains a polymerizable compound, the content of the polymerizable compound is preferably 5 to 80 mass % relative to the solid content in the composition, more preferably 10 to 60 mass %, and even more preferably 15 to 50 mass %. The solid content of a composition refers to the other components in the composition excluding the solvent. Even if the other components are in a liquid state, they are counted as solids.

[0051] The composition used to form the adhesive layer 26 (adhesive layer-forming composition) preferably contains a polymerization initiator from the viewpoint of adhesion to glass. The polymerization initiator may be, for example, a photopolymerization initiator. The photopolymerization initiator may be any one capable of generating radicals as active species upon irradiation with light, and known photopolymerization initiators may be used without any limitations. Specific examples include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyl dimethyl ketal, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholino(4-thiomethylphenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, 2-hydroxy-2-methyl-1-[4-(1-methyl Acetophenones such as 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one; 1,2-octanedione, 1-[4-(phenylthio)-, 2-(O-benzoyloxime)], and ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime); benzoyl Benzoins such as benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether; benzophenone, methyl ortho-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4'-methyl-diphenyl sulfide, 3,3',4,4'-tetra(t-butylperoxycarbonyl)benzophenone, 2,4,6-trimethylbenzophenone, 4-benzoyl-N,N-dimethyl-N-[2-(1-oxo-2 benzophenones such as (4-benzoylbenzyl)trimethylammonium bromide and (4-benzoylbenzyl)trimethylammonium chloride; thioxanthones such as 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, 1-chloro-4-propoxythioxanthone, and 2-(3-dimethylamino-2-hydroxy)-3,4-dimethyl-9H-thioxanthone-9-one mesochloride;Examples of suitable initiators include acylphosphine oxides such as 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, and bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide. Furthermore, examples of initiators that may be used in combination with the initiator include triethanolamine, triisopropanolamine, 4,4'-dimethylaminobenzophenone (Michler's ketone), 4,4'-diethylaminobenzophenone, 2-dimethylaminoethylbenzoic acid, ethyl 4-dimethylaminobenzoate, (n-butoxy)ethyl 4-dimethylaminobenzoate, isoamyl 4-dimethylaminobenzoate, 2-ethylhexyl 4-dimethylaminobenzoate, 2,4-diethylthioxanthone, and 2,4-diisopropylthioxanthone. The above-mentioned polymerization initiators and auxiliaries can be synthesized by known methods and are also commercially available. Commercially available radical photopolymerization initiators include Irgacure (127, 651, 184, 819, 907, 1870 (CGI-403 / Irg184 = 7 / 3 mixed initiator, 500, 369, 1173, 2959, 4265, 4263, etc.), OXE01) manufactured by BASF, KAYACURE (DETX-S, BP-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, MCA, etc.) manufactured by Nippon Kayaku, and Esacure (KIP100F, KB1, EB3, BP, X33, KT046, KT37, KIP150, TZT) manufactured by Sartomer, etc.

[0052] The content of the polymerization initiator contained in the composition used to form the adhesive layer 26 is not particularly limited, and may be adjusted appropriately within a range that allows the polymerization reaction of the polymerizable compound to proceed smoothly. When the composition used to form the adhesive layer contains a polymerization initiator, the content of the polymerization initiator is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the polymerizable compound contained in the composition.

[0053] The adhesive layer 26 may contain inorganic particles and / or resin particles. When the adhesive layer 26 contains inorganic particles and / or resin particles, unevenness is formed on the surface of the adhesive layer 26, and when the adhesive layer 26 is rolled up in a state where the adhesive layer 26 and the HC layer 14 are in direct contact with each other, friction between the adhesive layer 26 and the HC layer 14 can be reduced, allowing the adhesive layer 26 to be rolled up without wrinkles, which is preferable. Furthermore, when the adhesive layer 26 contains inorganic particles and / or resin particles, friction between the adhesive layer 26 and the object to be attached can be reduced and air remaining during pressure bonding can be suppressed, which is preferable. The inorganic particles contained in the adhesive layer 26 are preferably inorganic oxide particles, and more preferably examples thereof include silica (silicon dioxide) particles, aluminum oxide particles, titanium dioxide particles, and zirconium oxide particles, with silica particles being even more preferred. Preferred examples of the resin particles contained in the adhesive layer 26 include crosslinked acrylic particles, crosslinked acrylic-styrene particles, and crosslinked styrene particles. The resin particles may be spherical or irregular in shape. Two or more different types of matte particles may be used in combination. The average primary particle size of the resin particles is preferably 20% to 300% of the thickness of the adhesive layer 26, more preferably 50% to 200%, and particularly preferably 100% to 200 μm. By setting the average primary particle size of the resin particles within the above range, it is possible to impart unevenness to the adhesive layer 26 while preventing the resin particles from falling off.

[0054] Resin particles are also commercially available, and examples thereof include cross-linked acrylic resins MX-40T, MX-80H3wT, MX-150, MX-180TA, MX-300, MX-500, MX-1000, MX-1500H, MR-2HG, MR-7HG, MR-10HG, MR-3GSN, MR-5GSN, MR-7G, MR-10G, MR-5C, and MR-7GC manufactured by Soken Chemical & Engineering Co., Ltd., styryl resin-based SX-350H and SX-500H, and acrylic resins MBX-5, MBX-8, MBX-12, and MBX-1 manufactured by Sekisui Plastics Co., Ltd. Examples of suitable resins include SBX-5, MBX-20, MB20X-5, MB30X-5, MB30X-8, MB30X-20, SBX-6, SBX-8, SBX-12, SBX-17, SSX-101, SSX-102, SSX-103, SSX-105, SSX-108, and SSX-110, as well as polyolefin resins manufactured by Mitsui Chemicals, Inc., such as Chemipearl W100, W200, W300, W308, W310, W400, W401, W405, W410, W500, WF640, W700, W800, W900, W950, and WP100.

[0055] The content of the resin particles in the adhesive layer 26 is not particularly limited, but is preferably 0.1% by mass or more, and more preferably 0.5% by mass or more, relative to the total mass of the adhesive layer 26. There is no particular upper limit, but it is preferably 10% by mass or less, and more preferably 3% by mass or less.

[0056] The inorganic particles are preferably made up of primary particles, with secondary particles being formed by aggregation of the primary particles. The average primary particle size of the inorganic particles is not particularly limited, but is preferably 5 to 50 nm, more preferably 5 to 15 nm. The average secondary particle size of the inorganic particles is not particularly limited, but is preferably 100 to 500 nm.

[0057] The content of inorganic particles in adhesive layer 26 is not particularly limited, but is preferably 1% by mass or more, and more preferably 9% by mass or more, relative to the total mass of adhesive layer 26. There is no particular upper limit, but it is preferably 40% by mass or less, and more preferably 30% by mass or less.

[0058] The average primary particle size of the inorganic particles is measured by observation under a transmission electron microscope. Specifically, the diameters of the circles circumscribing the primary particles are determined for 50 randomly selected primary particles, and the arithmetic mean of the diameters is taken as the average primary particle diameter. The observation magnification of the transmission electron microscope is set to an arbitrary magnification between 500,000 and 5,000,000 that allows the primary particle diameter to be determined. The average secondary particle diameter is a value measured by spherical fitting (refractive index 1.46) using a laser diffraction / scattering particle size distribution analyzer, such as MicroTrac MT3000 manufactured by MicroTrac-Bell.

[0059] The adhesive layer 26 may include a leveling agent. As the leveling agent, a known leveling agent can be used, for example, a surfactant, and among them, a fluorine-based surfactant and a silicone-based surfactant are preferable. The fluorine content in the fluorine-containing surfactant is preferably 3 to 40 mass%, more preferably 5 to 30 mass%, and even more preferably 7 to 25 mass%. Fluorine-containing surfactants having a fluorine content within this range are effective in terms of the uniformity of the thickness of the coating film and the liquid saving properties.

[0060] The content of the leveling agent in the adhesive layer 26 is not particularly limited, but is preferably 0.005 to 0.5 mass % relative to the total mass of the adhesive layer 26, and more preferably 0.01 to 0.1 mass %.

[0061] The adhesive layer 26 is preferably formed by applying an adhesive layer-forming composition. The adhesive layer-forming composition is a composition that contains the above-mentioned components and is used to form the adhesive layer 26 . From the viewpoint of coating properties, the adhesive layer-forming composition preferably contains a solvent. The type of solvent is not particularly limited, and examples thereof include water and organic solvents, with organic solvents being preferred, including ketones, alkyl halides, amides, sulfoxides, heterocyclic compounds, hydrocarbons, esters, and ethers.

[0062] The method for applying the adhesive layer-forming composition is not particularly limited, and examples thereof include wire bar coating, curtain coating, extrusion coating, direct gravure coating, reverse gravure coating, die coating, spin coating, dip coating, spray coating, and slide coating.

[0063] The coating film obtained by coating may be subjected to a drying treatment as required. The drying treatment may be a heat treatment. The heating temperature in the heat treatment is not particularly limited, but is preferably 50 to 150° C., more preferably 60 to 140° C. The heating time is not particularly limited, but is preferably 0.5 to 20 minutes, more preferably 0.5 to 10 minutes.

[0064] The surface of the formed adhesive layer 26 (the surface opposite to the reflective layer or polarization conversion layer) may be subjected to a surface treatment as needed. For example, the surface of the adhesive layer 26 may be subjected to a hydrophilization treatment in order to reduce the water contact angle of the surface of the adhesive layer 26. Examples of the hydrophilization treatment include plasma treatment, ultraviolet irradiation treatment, corona treatment, and electron beam irradiation treatment, with corona treatment being preferred. The conditions for the hydrophilic treatment are appropriately selected depending on the type of treatment to be carried out, and are preferably adjusted so that the water contact angle of the surface of the adhesive layer 26 falls within the range described above.

[0065] As described above, in the laminate 10 of the present invention, the thickness of the adhesive layer 26 is greater than 100 μm. By virtue of this configuration, the laminate 10 of the present invention can suppress the generation of bubbles due to foreign matter even when the foreign matter is present between the substrate and the adhesive layer 26, and the bubbles disappear as the air around the defect dissolves in the adhesive layer 26. As a result, the laminate 10 of the present invention significantly suppresses the generation of bubble-like defects in a bonded product in which the laminate 10 is bonded to a substrate such as a windshield glass.

[0066] As described above, the head-up display system is configured by attaching a reflective film to a windshield glass. The reflective film is attached to an object such as the windshield glass by using an adhesive layer provided on the surface of the reflective film.

[0067] In this case, foreign matter such as dust often exists between the adhesive layer of the reflective film and the object to be stuck, but if this foreign matter is small, it does not cause any problems. However, if a foreign object, such as a human hair, is present between the adhesive layer and the object to be bonded and is large in size compared to the adhesive layer, when the adhesive layer (laminate) and the object to be bonded are bonded together with the foreign object sandwiched between them, the adhesive layer around the foreign object will be raised by the foreign object, resulting in bubble-like defects in the bonded product originating from the foreign object. In the case of a head-up display system, for example, such bubble-like defects can cause a decrease in the visibility of the projected image.

[0068] In contrast, in the laminate 10 of the present invention, the thickness of the adhesive layer 26 for laminating the laminate 10 to the object to be laminated is greater than 100 μm. Therefore, even if the foreign matter sandwiched between the adhesive layer 26 and the object to be bonded is large, the adhesive layer 26 has a sufficient thickness so that the foreign matter can be suitably wrapped and embedded in the adhesive layer 26, and the air around the defect dissolves in the adhesive layer 26, thereby eliminating the air bubbles. As a result, the laminate 10 of the present invention can significantly reduce bubble-like defects caused by the lifting of the adhesive layer due to the foreign matter. In particular, as described above, when the laminated body is formed and then further heat-pressed using an autoclave, the adhesive layer 26 is softened by heating in the autoclave, and the softened adhesive layer 26 has a sufficient thickness, so that foreign matter can be more suitably wrapped and embedded in the adhesive layer 26. In this case, lifting of the adhesive layer 26 due to foreign matter can be more suitably prevented, and bubble-like defects caused by this lifting can be further significantly reduced.

[0069] The thickness (average thickness) of the adhesive layer 26 is preferably 150 μm or more, more preferably 300 μm or more, and even more preferably 500 μm or more, from the viewpoints of the embedding of the above-mentioned foreign matter, the amount of dissolved air bubbles, adhesion to the object to be pasted, and adhesion to the adjacent layer in the laminate (polarization conversion layer 24 in the illustrated example). There is no particular upper limit to the thickness of the adhesive layer 26, but from the viewpoint of surface hardness, it is preferably 10,000 μm or less. The method for measuring the average thickness is to cut the adhesive layer 26 with a microtome to cut out a cross section, observe the cross section using an optical microscope, measure the thickness at three different positions on the adhesive layer 26, and calculate the average value (arithmetic mean value) of the measured values ​​to obtain the average thickness.

[0070] The adhesive layer 26 may have a single layer structure or a multi-layer structure of two or more layers. When the adhesive layer 26 has a multi-layer structure, the average total thickness of the adhesive layer 26 may be within the above range.

[0071] The laminate 10 of the present invention, having an adhesive layer with the above thickness, can suppress the occurrence of defects due to foreign matter when it is attached to an object to be attached.

[0072] (protective film) The laminate 10 of the present invention may have a protective film 12 on the surface.

[0073] The protective film 12 is provided on the surface of the laminate 10 opposite to the adhesive layer 26 as shown in FIG. The protective film 12 may be laminated when the autoclave treatment is carried out, and may be laminated, for example, before the vacuum thermocompression bonding or before the autoclave treatment after the vacuum thermocompression bonding. By providing such a protective film 12, it is possible to prevent the hard coat layer 14 and the like from being damaged during autoclave treatment. The protective film 12 may be peeled off after autoclaving when it is no longer needed.

[0074] Materials for forming the protect film 12 include resins such as polyethylene resins, polypropylene resins, polystyrene resins, and polyethylene terephthalate resins, nitrile rubbers such as acrylonitrile-butadiene rubbers, rubbers such as butyl rubber and acrylic rubber, and thermoplastic elastomers such as thermoplastic polyolefin elastomer (TPO), thermoplastic polyurethane elastomer (TPU), thermoplastic polyester elastomer (TPEE), thermoplastic polyamide elastomer (TPAE), diene elastomers (1,2-polybutadiene, etc.), and elastomers such as silicone elastomers and fluorine-based elastomers. A film formed from one or more of these materials in a single layer or multilayer configuration can be used as the protect film 12. As the material for the protective film, polyethylene terephthalate resin is preferred in terms of oxygen permeability coefficient.

[0075] The thickness of the protective film 12 is not particularly limited, but is preferably 25 μm or more, more preferably 75 μm or more, and even more preferably 125 μm or more. There is no particular upper limit to the thickness of the protective film 12, but it is often 500 μm or less.

[0076] The tensile modulus of the protective film 12 is not particularly limited, but is preferably 0.001 GPa or more, more preferably 0.01 GPa or more, even more preferably 0.1 GPa or more, and particularly preferably 1.0 GPa or more. There is no particular upper limit to the tensile modulus of the protective film 12, but it is often 12.0 GPa or less.

[0077] The tensile modulus of the protective film 12 can be changed, for example, by the material constituting the protective film 12. In general, the tensile modulus tends to increase by increasing the molecular weight and / or crystallinity of the resin or elastomer. Furthermore, the tensile modulus of the protective film 12 in the stretching direction can be increased by stretching it. When the protection film 12 is made up of multiple layers, the tensile modulus refers to the tensile modulus of the protection film as a laminate.

[0078] It is desirable that the protective film 12 shrinks when heated. Generally, the protective film 12 is also stretched during its manufacturing process, and residual stress from the stretching remains. This residual stress can be utilized to cause thermal shrinkage by heating the film to conform to the curved surface. The temperature at which the protective film 12 thermally shrinks varies depending on the material of the protective film 12, but it is preferable that it shrinks in the range of 80 to 200°C, and more preferably in the range of 90 to 140°C, which is the heat treatment temperature in a typical curved surface conforming process.

[0079] The protective film 12 may have an adhesive layer on at least one side, or may be a self-adhesive protective film having adhesive properties.

[0080] In order to reduce the oxygen permeability coefficient, the protective film 12 may be vapor-deposited with an inorganic material such as silica or alumina, and one or more overcoats may be further formed on the vapor-deposited surface.

[0081] (Hard coat layer) The laminate 10 of the present invention may have a hard coat layer (HC layer) 14 . The laminate 10 has the HC layer 14, which provides abrasion resistance that makes it difficult to scratch even when rubbed with a hard substance, scratch resistance that makes it difficult to scratch even when pressed with a hard substance, and stain resistance that makes it easy to wipe off dirt even when dirt adheres to it.

[0082] The HC layer 14 is preferably formed by polymerizing and curing at least one compound selected from the group consisting of polysiloxane-containing compounds having polymerizable groups in their molecules and fluorine-containing compounds having polymerizable groups in their molecules with a polymerizable compound other than these compounds, which has a polymerizable group in its molecule, as described below. It is more preferable that these polymerizable groups are radically polymerizable groups. This allows the compound selected from the group consisting of polysiloxane-containing compounds and fluorine-containing compounds to exist in a bonded state with the polymerizable compound forming the HC layer 14, thereby providing superior antifouling properties. When the compound selected from the group consisting of polysiloxane-containing compounds and fluorine-containing compounds has a polymerizable group, the polymerizable group in the compound selected from the group consisting of polysiloxane-containing compounds and fluorine-containing compounds described below reacts to form a bond and is present in the HC layer 14.

[0083] When the HC layer 14 has a laminate structure of two or more layers described below, it is preferable that the compound selected from the group consisting of polysiloxane-containing compounds and fluorine-containing compounds is contained in at least the HC layer farthest from the transparent resin layer 16, and more preferably only in the HC layer farthest from the transparent resin layer 16. When at least one compound selected from the group consisting of polysiloxane-containing compounds having a polymerizable group in the molecule and fluorine-containing compounds having a polymerizable group in the molecule is used, it is preferable that the HC layer 14 farthest from the transparent resin layer is a cured film of at least the above compound, and more preferably only the HC layer 14 farthest from the transparent resin layer is a cured film of the above compound. Specific embodiments of the HC layer 14 will be described below, but the present invention is not limited to the following embodiments.

[0084] The fluorine-containing compound is not particularly limited, and any compound having a fluorine atom in the molecule can be used as long as it can impart abrasion resistance, antifouling properties, etc. to the HC layer 14. As the fluorine-containing compound, a fluorine-containing antifouling agent that exhibits the properties of an antifouling agent is preferably used.

[0085] The fluorine-containing compound may be any of a monomer, oligomer, and polymer. The fluorine-containing compound preferably has a substituent that contributes to bond formation or compatibility with other components (e.g., polysiloxane-containing compounds, polymerizable monomers that are components of resins, and resins) in the HC layer 14. The substituents may be the same or different, and preferably there are multiple substituents. The substituent is preferably a polymerizable group, and may be any polymerizable reactive group exhibiting any one of radical polymerization, cationic polymerization, anionic polymerization, condensation polymerization, and addition polymerization, and preferred examples of the substituent include an acryloyl group, a methacryloyl group, a vinyl group, an allyl group, a cinnamoyl group, an epoxy group, an oxetanyl group, a hydroxyl group, a polyoxyalkylene group, a carboxyl group, and an amino group. Among these, a radical polymerizable group is preferred, and an acryloyl group or a methacryloyl group is more preferred. The fluorine-containing compound may be a polymer or oligomer with a compound not containing a fluorine atom.

[0086] The polysiloxane-containing compound in the present invention is not particularly limited, and examples thereof include compounds having a polysiloxane structure in the molecule. The polysiloxane structure of the polysiloxane-containing compound may be any of linear, branched, and cyclic. As the polysiloxane-containing compound, a polysiloxane antifouling agent exhibiting antifouling properties is preferably used.

[0087] The content of the polysiloxane-containing compound in the curable composition for forming an HC layer is preferably 0.01 to 5 mass%, more preferably 0.1 to 5 mass%, even more preferably 0.5 to 5 mass%, and particularly preferably 0.5 to 2 mass%, based on the total solid content in the curable composition for forming an HC layer. When the HC layer 14 has a laminated structure of two or more layers as described below, the amount refers to the amount added in the HC layer-forming curable composition that forms the HC layer 14 containing a polysiloxane compound.

[0088] The HC layer 14 can be obtained by irradiating an HC layer-forming curable composition with active energy rays and curing it. In this specification, the term "active energy rays" refers to ionizing radiation, and includes X-rays, ultraviolet rays, visible light, infrared rays, electron beams, α rays, β rays, and γ rays.

[0089] The curable composition for forming the HC layer 14 contains at least one component that has the property of being cured by irradiation with active energy rays (hereinafter, this component will also be referred to as an "active energy ray-curable component"). The active energy ray-curable component is preferably at least one polymerizable compound selected from the group consisting of radically polymerizable compounds and cationically polymerizable compounds. In this specification, a "polymerizable compound" refers to a compound having a polymerizable group in its molecule, and there may be at least one polymerizable group in one molecule. The polymerizable group is a group that can participate in a polymerization reaction, and specific examples include groups contained in various polymerizable compounds described below. In addition, examples of polymerization reactions include various polymerization reactions such as radical polymerization, cationic polymerization, and anionic polymerization. The HC layer 14 is preferably obtained by irradiating with active energy rays a curable composition for forming the HC layer, which contains at least one compound selected from the group consisting of polysiloxane-containing compounds having polymerizable groups in their molecules and fluorine-containing compounds having polymerizable groups in their molecules, and a polymerizable compound other than these compounds having polymerizable groups in their molecules, to polymerize and harden the composition. In this case, the polymerizable groups of the polysiloxane-containing compound, the fluorine-containing compound, and the polymerizable compound are more preferably radically polymerizable groups. The HC layer 14 may have a single layer structure or a laminated structure of two or more layers, and is preferably an HC layer having a single layer structure or a laminated structure of two or more layers, as described in detail below.

[0090] A preferred embodiment of the curable composition for forming a single-layer HC layer is a curable composition for forming a single-layer HC layer, which includes at least one polymerizable compound having two or more ethylenically unsaturated groups per molecule. The ethylenically unsaturated group refers to a functional group containing an ethylenically unsaturated double bond. A preferred embodiment of the curable composition for forming a single-layer HC layer is a curable composition for forming a single-layer HC layer, which includes at least one radically polymerizable compound and at least one cationically polymerizable compound.

[0091] The curable composition for forming an HC layer preferably contains a polymerization initiator, and more preferably contains a photopolymerization initiator. The curable composition for forming an HC layer containing a radical polymerizable compound preferably contains a radical photopolymerization initiator, and the curable composition for forming an HC layer containing a cationic polymerizable compound preferably contains a cationic photopolymerization initiator. Only one type of radical photopolymerization initiator may be used, or two or more types with different structures may be used in combination. This also applies to cationic photopolymerization initiators. Each photopolymerization initiator will be explained below in order.

[0092] The radical photopolymerization initiator may be any one that can generate radicals as active species upon irradiation with light, and known radical photopolymerization initiators can be used without any restrictions. The radical photopolymerization initiator and the auxiliary agent can be synthesized by a known method, and are also available as commercially available products. Preferred examples of commercially available radical photopolymerization initiators include Irgacure (127, 651, 184, 819, 907, 1870 (CGI-403 / Irg184=7 / 3 mixed initiator, 500, 369, 1173, 2959, 4265, 4263, etc.), OXE01, etc.) manufactured by BASF, KAYACURE (DETX-S, BP-100, BDMK, CTX, BMS, 2-EAQ, ABQ, CPTX, EPD, ITX, QTX, BTC, MCA, etc.) manufactured by Nippon Kayaku, and Esacure (KIP100F, KB1, EB3, BP, X33, KT046, KT37, KIP150, TZT, etc.) manufactured by Sartomer.

[0093] The content of the radical photopolymerization initiator in the curable composition for forming the HC layer is not particularly limited, and may be appropriately adjusted within a range in which the polymerization reaction (radical polymerization) of the radical polymerizable compound proceeds smoothly. The content is preferably 0.1 to 20 parts by mass, more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the radical polymerizable compound contained in the curable composition for forming the HC layer.

[0094] The cationic photopolymerization initiator may be any one that can generate cations as active species upon irradiation with light, and known cationic photopolymerization initiators can be used without any restrictions.

[0095] As the cationic photopolymerization initiator, diazonium salts, iodonium salts, sulfonium salts, and minium salts are preferred from the viewpoint of the sensitivity of the photopolymerization initiator to light, the stability of the compound, etc. Furthermore, iodonium salts are preferred from the viewpoint of weather resistance.

[0096] Specific examples of commercially available iodonium salt-based cationic photopolymerization initiators include B2380 manufactured by Tokyo Chemical Industry Co., Ltd., BBI-102 manufactured by Midori Chemical Industry Co., Ltd., WPI-113 manufactured by Wako Pure Chemical Industries, Ltd., WPI-124 manufactured by Wako Pure Chemical Industries, Ltd., WPI-169 manufactured by Wako Pure Chemical Industries, Ltd., WPI-170 manufactured by Wako Pure Chemical Industries, Ltd., and DTBPI-PFBS manufactured by Toyosei Chemical Industry Co., Ltd.

[0097] Specific examples of iodonium salt compounds that can be used as cationic photopolymerization initiators include the following compounds PAG-1 and PAG-2.

[0098] [ka]

[0099] [ka]

[0100] The content of the cationic photopolymerization initiator in the curable composition for forming the HC layer is not particularly limited, and may be appropriately adjusted within a range in which the polymerization reaction (cationic polymerization) of the cationic polymerizable compound proceeds smoothly. The content is preferably 0.1 to 200 parts by mass, more preferably 1 to 150 parts by mass, and even more preferably 2 to 100 parts by mass, relative to 100 parts by mass of the cationic polymerizable compound.

[0101] Other photopolymerization initiators include those described in paragraphs 0052 to 0055 of JP-A No. 2009-204725, the contents of which are incorporated herein by reference.

[0102] -Components that may be optionally contained in the curable composition for forming the HC layer- The curable composition for forming the HC layer contains at least one component that has the property of being cured by irradiation with active energy rays and a compound selected from the group consisting of polysiloxane-containing compounds and fluorine-containing compounds, and may optionally contain, and preferably contains, at least one polymerization initiator, the details of which are as described above.

[0103] The curable composition for forming an HC layer preferably contains a solvent. The solvent is preferably an organic solvent, and one or more organic solvents can be used by mixing them in any ratio. Specific examples of the organic solvent include alcohols such as methanol, ethanol, propanol, n-butanol, and i-butanol; ketones such as acetone, methyl isobutyl ketone, methyl ethyl ketone, and cyclohexanone; cellosolves such as ethyl cellosolve; aromatics such as toluene and xylene; glycol ethers such as propylene glycol monomethyl ether; acetate esters such as methyl acetate, ethyl acetate, and butyl acetate; and diacetone alcohol. Among these, it is preferable to use cyclohexanone, methyl ethyl ketone, methyl isobutyl ketone, butyl acetate, isopropyl acetate and methyl acetate in any desired ratio.

[0104] The amount of solvent in the curable composition for forming an HC layer can be adjusted as appropriate within a range that ensures the coating suitability of the composition. The content of the solvent is preferably 50 to 500 parts by mass, more preferably 80 to 200 parts by mass, per 100 parts by mass of the total amount of the polymerizable compound and the photopolymerization initiator. The solid content of the HC-forming curable composition is preferably 10 to 90 mass %, more preferably 50 to 80 mass %, and even more preferably 65 to 75 mass %, based on the total mass of the HC-forming curable composition.

[0105] In addition to the above components, the curable composition for forming the HC layer may contain any amount of one or more known additives, such as a surface modifier, a polymerization inhibitor, and polyrotaxane. For details thereof, see, for example, paragraphs 0032 to 0034 of JP 2012-229412 A. However, the additives are not limited to these, and various additives that can generally be added to a curable composition for forming an HC layer can be used.

[0106] The curable composition for forming the HC layer can be prepared by mixing the various components described above simultaneously or sequentially in any order. The preparation method is not particularly limited, and a known mixer or the like can be used for preparation.

[0107] The thickness of the HC layer 14 is preferably 1 μm or more, more preferably 1 to 100 μm, even more preferably 1 to 20 μm, particularly preferably 3 to 20 μm, and most preferably 5 to 20 μm. The thickness of the HC layer 14 can be measured by cutting the HC layer 14 with a microtome to cut out a cross section, staining it overnight with an approximately 3% by mass aqueous solution of osmium tetroxide, cutting out the surface again, and observing the cross section using a SEM (Scanning Electron Microscope).

[0108] The HC layer can be formed by applying the curable composition for forming the HC layer and irradiating it with active energy rays. The coating can be carried out by a known coating method such as dip coating, air knife coating, curtain coating, roller coating, die coating, wire bar coating, or gravure coating. The HC layer can also be formed as an HC layer having a laminated structure of two or more layers (for example, about 2 to 5 layers) by simultaneously or successively applying two or more different compositions.

[0109] The applied curable composition for forming an HC layer is irradiated with active energy rays, thereby forming an HC layer. For example, when the HC layer-forming curable composition contains a radical polymerizable compound, a cationic polymerizable compound, a radical photopolymerization initiator, and a cationic photopolymerization initiator, the polymerization reactions of the radical polymerizable compound and the cationic polymerizable compound can be initiated and progressed by the action of the radical photopolymerization initiator and the cationic photopolymerization initiator, respectively. The wavelength of the irradiated light can be determined depending on the type of polymerizable compound and polymerization initiator used. Examples of light sources for the light irradiation include high-pressure mercury lamps, ultra-high-pressure mercury lamps, carbon arc lamps, metal halide lamps, xenon lamps, chemical lamps, electrodeless discharge lamps, and LEDs (light-emitting diodes), all of which emit light in the 150 to 450 nm wavelength range. The light irradiation dose is 30 to 3000 mJ / cm 2 is preferred, and 100 to 1500 mJ / cm 2 It is more preferable that the drying treatment is carried out before or after the light irradiation, or both, if necessary. The drying treatment can be carried out by blowing hot air onto the film, placing the film in a heating furnace, transporting the film in the heating furnace, or the like. When the curable composition for forming an HC layer contains a solvent, the heating temperature is not particularly limited as long as it is set to a temperature at which the solvent can be dried and removed. Here, the heating temperature refers to the temperature of the hot air or the atmospheric temperature inside the heating furnace.

[0110] When the laminate 10 has the HC layer 14 , the HC layer 14 is desirably disposed between the protection film 12 and the transparent resin layer 16 .

[0111] (Transparent resin layer) The laminate 10 may include a transparent resin layer 16 . The transparent resin layer 16 supports the entire laminate 10 of the present invention. The material of the transparent resin layer 16 is not particularly limited, but it is preferable that it is transparent in the visible light region.

[0112] There are no particular limitations on the material of the transparent resin layer 16. Examples of the transparent resin layer 16 include plastic films such as polyesters such as polyethylene terephthalate (PET), polycarbonates, acrylic resins, epoxy resins, polyurethanes, polyamides, polyimides, polyolefins, cellulose derivatives, and silicones. The transparent resin layer 16 is preferably a cellulose acylate film or a polyethylene terephthalate film.

[0113] The thickness of the transparent resin layer 16 is not particularly limited, but is preferably 25 μm or more, more preferably 40 μm or more. There is no particular upper limit to the thickness of the transparent resin layer 16, but it is often 500 μm or less.

[0114] The tensile modulus of the transparent resin layer 16 is not particularly limited, but is preferably 1.0 GPa or more, more preferably 2.5 GPa or more, even more preferably 3.0 GPa or more, particularly preferably 3.5 GPa or more, and most preferably 4.0 GPa or more. There is no particular upper limit, but it is often 12.0 GPa or less.

[0115] The tensile modulus of the transparent resin layer 16 can be varied, for example, depending on the type of resin constituting the transparent resin layer 16. Generally, the tensile modulus tends to increase by increasing the molecular weight and / or crystallinity of the resin. Furthermore, the tensile modulus of the transparent resin layer 16 in the stretching direction can be increased by stretching the transparent resin layer 16. Even when the transparent resin layer 16 is made up of multiple layers, the tensile modulus refers to the tensile modulus of the transparent resin layer 16 as a whole.

[0116] The transparent resin layer 16 may be formed by any method, for example, a melt casting method or a solution casting method.

[0117] (melt film forming method, smoothing) When the transparent resin layer 16 is formed by a melt film-forming method, the melt film-forming method preferably includes a melting step of melting the resin in an extruder, a step of extruding the molten resin into a sheet from a die, and a step of forming the molten resin into a film. Depending on the resin material, a filtering step of the molten resin may be provided after the melting step, or the molten resin may be cooled when extruded into a sheet. A specific solution film forming method will be described below, but the present invention is not limited thereto.

[0118] The method for producing the transparent resin layer preferably includes a melting step of melting the resin in an extruder, a filtration step of filtering the molten resin through a filtration device equipped with a filter, a film forming step of extruding the filtered resin into a sheet form from a die and bringing it into close contact with a cooling drum to cool and solidify it to form an unstretched transparent resin layer, and a stretching step of stretching the unstretched transparent resin layer uniaxially or biaxially. This configuration allows the production of a transparent resin layer. If the pore size of the filter used in the filtration process of the molten resin is 1 μm or less, foreign matter can be sufficiently removed. As a result, the surface roughness of the obtained transparent resin layer in the film width direction can be controlled. Specifically, the method for forming the transparent resin layer can include the following steps.

[0119] [Melting process] The method for producing the transparent resin layer includes a melting step of melting the resin in an extruder. The resin or a mixture of resin and additives is preferably dried to a moisture content of 200 ppm or less and then introduced into a single-screw (single-screw) or twin-screw extruder and melted. To prevent resin decomposition, it is also preferable to melt the resin in nitrogen or vacuum. Detailed conditions can be found in Japanese Patent No. 4962661, paragraphs 0051-0052 (U.S. Patent Application Publication No. 2013 / 0100378, paragraphs 0085-0086), and the contents of these publications are incorporated herein by reference. The extruder is preferably a single-screw kneading extruder. Furthermore, it is also preferable to use a gear pump to increase the precision of feeding the molten resin (melt).

[0120] [Filtration process] The method for producing the transparent resin layer includes a filtration step of passing the molten resin through a filtration device equipped with a filter, and the pore size of the filter used in the filtration step is preferably 1 μm or less. Only one set of filtration devices having filters with pore sizes within this range may be installed in the filtration step, or two or more sets may be installed.

[0121] [Film forming process] The method for producing the transparent resin layer includes a film forming step in which the filtered resin is extruded through a die into a sheet, which is then brought into close contact with a cooling drum and cooled and solidified to form an unstretched transparent resin layer.

[0122] When the resin (melt containing the resin) that has been melted (and kneaded) and filtered is extruded from a die into a sheet, it may be extruded as a single layer or as a multilayer. When extruding as a multilayer, for example, a layer containing an ultraviolet absorber and a layer not containing an ultraviolet absorber may be laminated, and more preferably, a three-layer structure in which a layer containing an ultraviolet absorber is the inner layer is preferred in terms of being able to suppress deterioration of the polarizer due to ultraviolet rays and to suppress bleeding out of the ultraviolet absorber. When the transparent resin layer is produced by extrusion in multiple layers, the thickness of the inner layer of the resulting transparent resin layer is preferably 50 to 99%, more preferably 60 to 99%, and even more preferably 70 to 99% of the total thickness of the layers. Such lamination can be performed using a feed block die and a multi-manifold die.

[0123] According to paragraph 0059 of JP 2009-269301 A, it is preferable to extrude a resin (a melt containing a resin) into a sheet form from a die onto a cooling drum (casting drum), cool and solidify it, and obtain an unstretched transparent resin layer (raw sheet).

[0124] In the method for producing the transparent resin layer, the temperature of the resin extruded from the die is preferably 280 to 320°C, more preferably 285 to 310°C. It is preferable that the temperature of the resin extruded from the die in the melting step is 280°C or higher, since this reduces the amount of unmelted raw resin and suppresses the generation of foreign matter. It is preferable that the temperature of the resin extruded from the die in the melting step is 320°C or lower, since this reduces the decomposition of the resin and suppresses the generation of foreign matter. The temperature of the resin extruded from the die can be measured without contacting the surface of the resin using a radiation thermometer (manufactured by Hayashi Denko, model number: RT61-2, emissivity 0.95).

[0125] In the method for producing the transparent resin layer, it is preferable to use an electrostatically applied electrode when the resin is brought into close contact with the cooling drum in the film forming step, which allows the resin to be tightly adhered to the cooling drum without roughening the film surface.

[0126] In the method for producing the transparent resin layer, the temperature of the resin when it is brought into close contact with the cooling drum (at the point where the molten resin extruded from the die first comes into contact with the cooling drum) is preferably 280°C or higher. This increases the electrical conductivity of the resin, allowing it to be tightly adhered to the cooling drum by applying static electricity, and suppressing roughness of the film surface. The temperature of the resin when it is placed on the cooling drum can be measured without contact with the surface of the resin using a radiation thermometer (manufactured by Hayashi Denko, model number: RT61-2, emissivity 0.95).

[0127] [Stretching process] The method for producing the transparent resin layer includes a stretching step of uniaxially or biaxially stretching an unstretched transparent resin layer. In the longitudinal stretching process (a process of stretching in the same direction as the film transport direction), the transparent resin layer is preheated, and then, while the transparent resin layer is heated, it is stretched in the transport direction using a group of rollers with different peripheral speeds (i.e., different transport speeds).

[0128] The preheating temperature in the longitudinal stretching step is preferably from Tg - 40°C to Tg + 60°C, more preferably from Tg - 20°C to Tg + 40°C, and even more preferably from Tg to Tg + 30°C, relative to the glass transition temperature (Tg) of the transparent resin layer. The stretching temperature in the longitudinal stretching step is preferably from Tg to Tg + 60°C, more preferably from Tg + 2°C to Tg + 40°C, and even more preferably from Tg + 5°C to Tg + 30°C. The stretching ratio in the longitudinal direction is preferably 1.0 to 2.5 times, and more preferably 1.1 to 2 times.

[0129] In addition to or instead of the longitudinal stretching step, the transparent resin layer is stretched transversely in the width direction by a transverse stretching step (a step of stretching in a direction perpendicular to the film conveying direction). In the transverse stretching step, for example, a tenter can be suitably used, and the transparent resin layer is stretched transversely by this tenter while holding both ends in the width direction with clips. This transverse stretching can increase the tensile modulus of the transparent resin layer.

[0130] The transverse stretching is preferably carried out using a tenter, and the stretching temperature is preferably from Tg to Tg + 60°C, more preferably from Tg + 2°C to Tg + 40°C, and even more preferably from Tg + 4°C to Tg + 30°C, relative to the glass transition temperature (Tg) of the transparent resin layer. The stretching ratio is preferably 1.0 to 5.0 times, more preferably 1.1 to 4.0 times. After the transverse stretching, it is also preferable to relax the transparent resin layer in either or both of the longitudinal and transverse directions.

[0131] Furthermore, it is preferable that the variation in thickness depending on location in both the width direction and the length direction be 10% or less, more preferably 8% or less, even more preferably 6% or less, particularly preferably 4% or less, and most preferably 2% or less.

[0132] The thickness variation can be determined as follows.

[0133] A 10 m (meter) sample of the stretched transparent resin layer is taken, and 20% of each end of the film width direction is removed. 50 samples are taken at equal intervals from the center of the film widthwise and lengthwise, and the thickness is measured.

[0134] Average thickness in the width direction Th TD-av , maximum value Th TD-max , and the minimum value Th TD-min Seeking (Th TD-max -Th TD-min )÷ Th TD-av ×100 [%] is the thickness variation in the width direction.

[0135] In addition, the average thickness in the longitudinal direction Th MD-av , maximum value Th MD-max , and the minimum value Th MD-min Seeking (Th MD-max -Th MD-min )÷ Th MD-av ×100 [%] is the thickness variation in the longitudinal direction.

[0136] The stretching step can improve the thickness accuracy of the transparent resin layer.

[0137] The stretched transparent resin layer can be wound into a roll in a winding process. At this time, the winding tension of the transparent resin layer is 0.02 kg / mm 2 It is preferable to do the following:

[0138] For other detailed conditions, the contents described in paragraphs 0134 to 0148 of JP 2015-224267 A for the melt-casting process and the contents described in JP 2007-137028 A for the stretching process can be incorporated into this specification in accordance with the present invention.

[0139] (Solution casting method, smoothing) When the transparent resin layer is formed by a solution casting method, it is preferable to include a step of casting a dope solution onto a casting band to form a casting film, a step of drying the casting film, and a step of stretching the casting film. Specifically, the transparent resin layer by the solution casting method is preferably formed by the method described in Japanese Patent No. 4889335. In the present invention, it is preferable to employ the following method. For example, JP-A-11-123732 discloses a method for slow drying in which the drying rate of the cast film is set to 300% by mass / min (=5% by mass / s) or less in terms of the solvent content on a dry basis. JP-A-2003-276037 also discloses a method for co-casting a multilayered cast film having a core layer (an intermediate layer) on both surfaces thereof, in which the viscosity of the dope for forming the core layer is increased to ensure the strength of the cast film and the viscosity of the dope for forming the outer layer is decreased. Furthermore, other preferred methods include a method in which the cast film is rapidly dried to form a film on the surface of the cast film, and the surface is smoothed by the leveling effect of the formed film, and a method in which the cast film is stretched.

[0140] It is desirable that the transparent resin layer 16 shrinks due to heat. When the laminate is made to conform to a curved glass surface, excess portions of the flat laminate are generated relative to the curved glass, which presumably makes it difficult to conform to the curved surface. However, it is preferable that the transparent resin layer 16 shrinks due to heat, so that the excess portions of the laminate shrink and can conform to the curved surface.

[0141] Generally, transparent resin layers are stretched during their manufacturing process, and residual stress resulting from the stretching remains. Therefore, this residual stress can be utilized to cause thermal shrinkage when heated to conform to the curved surface. It is presumed that this thermal shrinkage allows the layer to conform to the curved glass. Furthermore, insufficient conformance is likely to occur in areas of the glass near the periphery where the glass is most curved, but is unlikely to occur in areas where the glass is less curved. In contrast, a laminate using a thermally shrinkable transparent resin layer effectively prevents insufficient conformance in areas of the glass that are most curved. The mechanism of action is thought to be that in areas of the glass that are most curved, the laminate has the freedom to expand in the thickness direction, resulting in shrinkage in the planar direction, while in areas of the glass that are less curved, the laminate has the freedom to expand in the thickness direction, resulting in almost no shrinkage in the planar direction. The temperature at which the transparent resin layer 16 thermally shrinks varies depending on the material from which the transparent resin layer 16 is formed, but it is preferable that it shrinks in the range of 80 to 200°C, and more preferably in the range of 90 to 140°C, which is the heat treatment temperature in a typical curved surface conforming process. Heating to shrink the transparent resin layer 16 may be applied to the entire curved glass, or may be applied locally to a portion where the curvature is high and insufficient conformance is likely to occur.

[0142] The amount of shrinkage of the transparent resin layer 16 required to prevent insufficient conformance varies depending on the curvature and dimensions of the glass. The thermal shrinkage of the transparent resin layer 16 is not particularly limited as long as it satisfies the above-mentioned thermal shrinkage when formed into a laminate, but at 140°C, the average thermal shrinkage in the direction in which the thermal shrinkage is greatest and in the direction perpendicular to this direction is preferably 0.3 to 5.0%, more preferably 0.3 to 3.0%, and even more preferably 0.3 to 2.0%. The thermal shrinkage can be adjusted as appropriate by adjusting the stretching conditions when producing the transparent resin layer.

[0143] (phase contrast layer) The laminate 10 may include a retardation layer 18 . The retardation layer 18 changes the state of the incident polarized light by creating a phase difference (optical path difference) between two orthogonal polarized light components. For example, when an image display device (projector) of a head-up display system using the laminate 10 of the present invention emits linearly polarized projection light, and the laminate 10 of the present invention uses a cholesteric liquid crystal layer as the reflective layer 20, the retardation layer 18 converts the linearly polarized light into circularly polarized light in the rotation direction that is selectively reflected by the cholesteric liquid crystal layer, thereby enabling the projection light to be suitably reflected by the reflective layer 20 and displaying a bright projected image.

[0144] When the retardation layer 18 is disposed on the glass plate side facing the vehicle interior and provides optical compensation, the front retardation of the retardation layer may be set to a retardation that allows optical compensation. In this case, the retardation layer 18 preferably has a front retardation of 50 to 160 nm at a wavelength of 550 nm. Furthermore, when a windshield glass having the laminate is mounted on a vehicle, the angle of the slow axis is preferably 10 to 50° or −50 to −10°, with the direction corresponding to the vertically upward direction of the surface of the glass plate being defined as 0°.

[0145] Furthermore, as described above, when the retardation layer 18 converts linearly polarized light into circularly polarized light, the retardation layer 18 is preferably configured to give a front retardation of λ / 4, or may be configured to give a front retardation of 3λ / 4. The angle of the slow axis may be set so as to be oriented in a direction that converts incident linearly polarized light into circularly polarized light.

[0146] In this case, the retardation layer 18 preferably has a front retardation at a wavelength of 550 nm in the range of 100 to 450 nm, more preferably in the range of 120 to 200 nm or 300 to 400 nm, for example. The direction of the slow axis of the retardation layer 18 is preferably determined depending on the incident direction of projection light for displaying a projected image and the sense of helix of the cholesteric liquid crystal layer constituting the reflective layer 20 when the laminate 10 is used in a head-up display system.

[0147] The retardation layer 18 is not particularly limited and can be appropriately selected depending on the purpose. Examples of the retardation layer 18 include a stretched polycarbonate film, a stretched norbornene-based polymer film, a transparent film containing and oriented inorganic particles having birefringence such as strontium carbonate, a thin film formed by obliquely depositing an inorganic dielectric on a support, a film in which a polymerizable liquid crystal compound is uniaxially oriented and fixed in orientation, and a film in which a liquid crystal compound is uniaxially oriented and fixed in orientation.

[0148] Among them, a film in which a polymerizable liquid crystal compound is uniaxially aligned and fixed is a suitable example of the retardation layer 18. As an example, such a retardation layer 18 can be formed by applying a liquid crystal composition containing a polymerizable liquid crystal compound to a transparent substrate, a temporary support, or the surface of an alignment layer, forming the polymerizable liquid crystal compound in the liquid crystal composition into a nematic alignment in a liquid crystal state, and then fixing the alignment by curing.

[0149] The retardation layer 18 may be a layer obtained by applying a composition containing a polymer liquid crystal compound to the surface of a transparent substrate, a temporary support, an alignment layer, or the like, forming a nematic alignment in a liquid crystal state, and then fixing the alignment by cooling.

[0150] The thickness of the retardation layer 18 is not particularly limited, but is preferably 0.2 to 300 μm, more preferably 0.5 to 150 μm, and even more preferably 1.0 to 80 μm. The thickness of the retardation layer 18 formed from a liquid crystal composition is not particularly limited, but is preferably 0.2 to 10 μm, more preferably 0.5 to 5.0 μm, and even more preferably 0.7 to 2.0 μm.

[0151] (polarization conversion layer) The laminate 10 may include a polarization conversion layer 24 . For example, when a driver wearing polarized sunglasses drives a vehicle equipped with a head-up display system that uses the laminate of the present invention as a reflective film, the polarization conversion layer 24 enables the polarized sunglasses to function properly. In other words, the polarization conversion layer 24 is a layer that ensures the suitability of a vehicle equipped with a head-up display system that uses the laminate of the present invention for polarized sunglasses.

[0152] The external light that drivers perceive as dazzling, such as light reflected from puddles or the hood of their car, is often s-polarized light. For this reason, polarized sunglasses are usually designed to block s-polarized light. Here, the laminate 10 of the present invention uses a cholesteric liquid crystal layer as a suitable reflective layer 20. Therefore, external light that has entered the laminate 10 of the present invention is transmitted through the cholesteric liquid crystal layer, which is the reflective layer 20, and then is observed by the driver. However, s-polarized light (linearly polarized light) is converted into elliptically polarized light when it passes through the cholesteric liquid crystal layer. When elliptically polarized light enters the retardation layer 18 (λ / 4 layer), the retardation layer 18 cannot convert this elliptically polarized light back to s-polarized light, and the light enters the polarized sunglasses worn by the driver in an elliptically polarized or circularly polarized state. As mentioned above, polarized sunglasses block s-polarized light, but not elliptically polarized light. Therefore, in this case, polarized sunglasses cannot block external light that causes glare, such as light reflected by puddles and the hood, and the driver can still see it. The polarization conversion layer 24 eliminates such inconveniences by converting s-polarized light entering from the outside into elliptically polarized light, which then passes through the reflective layer 20 (cholesteric liquid crystal layer) and is then converted back to s-polarized light by the retardation layer 18. This effect will be described in detail later.

[0153] The polarization conversion layer 24 is a layer in which the helical orientation structure of a liquid crystal compound is fixed, and it is preferable that the pitch number x of the helical orientation structure and the film thickness y (unit: μm) of the polarization conversion layer satisfy all of the following relational expressions (a) to (c). 0.1≦x≦1.0 ··· Formula (a) 0.5≦y≦3.0 ··· Formula (b) 3000≦(1560×y) / x≦50000 ··· Formula (c) One pitch of the helical structure of a liquid crystal compound is one turn of the helix of the liquid crystal compound. In other words, one pitch is defined as the state in which the director of the helically aligned liquid crystal compound (the long axis direction in the case of rod-shaped liquid crystals) rotates 360°.

[0154] When the polarization conversion layer 24 has a helical structure of a liquid crystal compound, it exhibits optical rotation and birefringence for visible light, which has a wavelength shorter than the reflection peak wavelength in the infrared range. This allows for control of polarization in the visible range. By setting the pitch number x of the helical orientation structure of the polarization conversion layer 24 and the film thickness y of the polarization conversion layer within the above ranges, the polarization conversion layer can be given the function of optically compensating for visible light, or the function of converting linearly polarized light (p-polarized / s-polarized light) incident on the laminate into circularly polarized light (elliptically polarized light).

[0155] The polarization conversion layer 24 exhibits optical rotation and birefringence for visible light because the liquid crystal compound has a helical structure that satisfies the relational expressions (a) to (c). In particular, by setting the pitch P of the helical structure of the polarization conversion layer 24 to a length corresponding to the pitch P of the cholesteric liquid crystal layer whose selective reflection center wavelength is in the long-wavelength infrared region, the polarization conversion layer 24 exhibits high optical rotation and birefringence for short-wavelength visible light.

[0156] The relational expression (a) is "0.1≦x≦1.0". By setting the pitch number x of the helical structure to 0.1 or more, sufficient optical rotation and birefringence can be obtained, which is preferable. Furthermore, by setting the pitch number x of the helical structure to 1.0 or less, the optical rotation and birefringence are sufficient, and the desired elliptically polarized light is easily obtained.

[0157] The relationship (b) is "0.5≦y≦3.0". By setting the thickness y of the polarization conversion layer to 0.5 μm or more, sufficient optical rotation and birefringence can be obtained. By setting the thickness y of the polarization conversion layer to 3.0 μm or less, sufficient optical rotation and birefringence can be obtained, making it easier to obtain the desired elliptically polarized light.

[0158] The relationship (c) is 3000≦(1560×y) / x≦50000. By setting "(1560×y) / x" to 3000 or more, it is easy to obtain the desired elliptically polarized light. By setting "(1560×y) / x" to 50,000 or less, it is easy to obtain the desired elliptically polarized light.

[0159] In the present invention, the pitch number x of the spiral structure of the polarization conversion layer 24 is more preferably 0.1 to 0.8, and the film thickness y is more preferably 0.6 to 2.6 μm. Also, "(1560×y) / x" is more preferably 5000 to 13000.

[0160] That is, it is preferable that the polarization conversion layer 24 has a long pitch P of the spiral structure and a small pitch number x. Specifically, it is preferable that the helical pitch P of the polarization conversion layer 24 is equivalent to the pitch P of a cholesteric liquid crystal layer having a selective reflection center wavelength in the long infrared wavelength range, and that the pitch number x is small. More specifically, it is preferable that the helical pitch P of the polarization conversion layer 24 is equivalent to the pitch P of a cholesteric liquid crystal layer having a selective reflection center wavelength of 3000 to 10000 nm, and that the pitch number x is small. In such a polarization conversion layer 24, the selective reflection center wavelength corresponding to the pitch P is much longer than that of visible light, and therefore the polarization conversion layer 24 more suitably exhibits the optical rotation property and birefringence for visible light described above.

[0161] Such a polarization conversion layer 24 can be formed basically in the same way as a known cholesteric liquid crystal layer. However, when forming the polarization conversion layer 24, it is preferable to adjust the liquid crystal compound to be used, the chiral agent to be used, the amount of chiral agent added, the film thickness, etc. so that the pitch number x of the helical structure and the film thickness y [μm] of the polarization conversion layer 24 satisfy all of the relational expressions (a) to (c).

[0162] As described above, the laminate of the present invention has a reflective layer such as a cholesteric liquid crystal layer and an adhesive layer having a thickness of more than 100 μm, and further has the various layers described above as needed. The thickness of the laminate of the present invention may be appropriately set depending on the number of layers, the materials used to form each layer, the reflection characteristics of the projection light, and the like. The lower limit of the thickness of the laminate is not particularly limited, but is preferably 150 μm or more, more preferably 300 μm or more. The upper limit of the thickness of the laminate is not particularly limited, but is preferably 10,000 μm or less. The thickness of the laminate may be measured by the method described in the Examples below.

[0163] Furthermore, from the viewpoint of visibility of a displayed image (projected image) in a head-up display system, etc., the surface roughness Ra of the laminate is preferably 1 μm or less, and more preferably 0.5 μm or less. There is no particular lower limit for the surface roughness Ra of the laminate, but it is often 0.001 μm or more. The surface roughness Ra of the laminate is measured as follows.

[0164] (Surface roughness of laminate) The laminate is placed on a flat glass plate with the surface on the adhesive layer side in contact with the glass plate. This is placed in a rubber bag and the pressure is reduced to 10 kPa (0.1 atmospheres) using a vacuum pump. The temperature is then raised to 95°C under reduced pressure, held for 20 minutes, and then returned to room temperature and pressure. The laminate is then held in an autoclave (manufactured by Kurihara Seisakusho) at 130°C and 1.1 MPa (11 atmospheres) for 20 minutes to bond the laminate and glass substrate with the adhesive layer, yielding a glass sample. For laminates with a protective film, the protective film is peeled off after autoclave treatment. The surface of the above glass sample is measured using a 3D optical profiler (New View 7300, manufactured by Zygo) under the following conditions to obtain a surface profile of the laminate. Measuring lens: 1x Mode: Scan ·Measurement area: 33mm x 33mm Overlap: 25% The measurement and analysis software used was the Microscope Application of MetroPro ver. 8.3.2. Next, the Surface Map screen was displayed in the analysis software, and histogram data was obtained from the Surface Map screen. From the obtained histogram data, the surface roughness was calculated, and the surface roughness Ra value of the laminate was obtained.

[0165] The bonded body of the present invention comprises an object to be bonded and the laminate of the present invention bonded to the object to be bonded. The object to be pasted may have a curved surface, and various known objects can be used. Examples of the substrate include window glass, glass used in the interior and exterior of buildings, curved glass used in lenses, and resin substrates (resin layers) made of resins such as polycarbonate and polymethyl methacrylate. When the substrate is a resin substrate, a substrate made of polycarbonate resin is preferred from the viewpoint of impact resistance.

[0166] Another embodiment of the laminate of the present invention comprises a windshield glass and the laminate of the present invention attached to the windshield glass. There are no restrictions on the windshield glass, and various types of windshield glass (windshield glass) used in vehicles such as automobiles, ships, aircraft, trains, and motorcycles can be used. Therefore, the windshield glass may be a single sheet of glass or a laminated glass made up of multiple sheets of glass. Furthermore, the laminated glass may have an interlayer film such as polyvinyl butyral between the sheets, or may not have an interlayer film.

[0167] Such a laminate of the present invention is preferably produced by the production method described below. 2 and 3 conceptually show an example of a method for producing a bonded body of the present invention. The following description will be given taking as an example a case where the laminate of the present invention is attached to a windshield glass, however, the present invention is not limited thereto and various known objects can be used to attach the laminate. Examples of the substrate to which the adhesive film may be applied other than the windshield glass include the various types of glass and resin substrates mentioned above.

[0168] In the manufacturing method of this bonded body, first, a windshield glass 28 and the laminate 10 of the present invention are laminated together as shown in the upper part of Fig. 2. At this time, the lamination is performed so that the adhesive layer 26 of the laminate 10 faces the windshield glass 28. Next, as shown in the second row of FIG. 2, the container is placed in a bag 106 such as a rubber bag similar to the example shown in FIG. Here, depending on the curvature of the windshield, when laminating the laminate 10 of the present invention, wrinkles may occur in the laminate 10 as shown in the upper part of Figure 3 due to the laminate 10 being made to follow the curved shape of the windshield glass 28.

[0169] In order to suppress the above-mentioned wrinkles, the laminate 10 of the present invention has a bending stiffness coefficient S of 0.5×10 6[GPa·μm 3 When laminate 10 has the above-mentioned bending stiffness coefficient, large localized wrinkles are not generated by the pressure of bag 106, and laminate 10 is pressed by bag 106 in a state where small wrinkles are generated all over the surface, as shown in the middle part of FIG.

[0170] In the present invention, the average tensile modulus and average heat shrinkage for calculating the flexural rigidity coefficient S may be measured by the following methods. To measure the average tensile modulus, first, starting from one in-plane direction of the laminate, cut out specimens of a predetermined size with their length aligned in each direction rotated 45° clockwise from that direction. The cut specimens were then placed in a tensile tester with a chuck spacing of 100 mm in the measurement direction and stretched at a stretching rate of 300 mm / min at a measurement temperature of 25°C, increasing the chuck spacing, to obtain a stress-strain curve. The tensile modulus was calculated by linear regression of the resulting curve. The in-plane direction of the laminate corresponding to the length of the specimen showing the greatest tensile modulus of the specimen was defined as the first direction, and the direction perpendicular to the first direction was defined as the second direction. The average of the tensile modulus in the first direction and the tensile modulus in the second direction was defined as the average tensile modulus of the laminate. When measuring the average thermal shrinkage, first, using one in-plane direction of the laminate as a reference, cut out sample pieces of a predetermined size with their length aligned in each direction rotated 45° clockwise from that direction. Next, two reference lines are marked on the cut-out sample pieces in the width direction at intervals of 100 mm. The sample pieces are then placed in a heating oven at 140°C for 45 minutes without tension, and then cooled to room temperature, and the distance between the two reference lines is measured. The thermal shrinkage of the sample pieces is measured from the distances before and after the treatment. The in-plane direction of the laminate corresponding to the length direction of the test piece showing the greatest thermal shrinkage of each sample piece is defined as the first direction, and the direction perpendicular to the first direction is defined as the second direction. The average of the thermal shrinkage in the first direction and the thermal shrinkage in the second direction is defined as the average thermal shrinkage of the laminate.

[0171] The lower limit of the average tensile elastic modulus is not particularly limited, but is preferably 0.01 GPa or more, more preferably 0.1 GPa or more. The upper limit of the average tensile elastic modulus is not particularly limited, but is preferably 10.0 GPa or less, more preferably 8.0 GPa or less.

[0172] Furthermore, vacuum thermocompression bonding is performed in the same manner as above. That is, by heating while reducing the pressure inside the bag 106, the laminate 10 is pressed by the bag 106, and as a result, the laminate 10 is pressed against the windshield glass 28 and thermocompression bonded to form a laminate of the windshield glass 28 and the laminate 10. As described above, the adhesive layer 26 of the laminate 10 of the present invention has a thickness of more than 100 μm. Therefore, even if a large foreign object adheres between the windshield glass 28 and the adhesive layer 28, the sufficiently thick adhesive layer 28 can adequately embed the foreign object and dissolve the air around the foreign object into the adhesive layer 28. As a result, the laminate 10 of the present invention can significantly reduce bubble-like defects in the bonded body caused by the adhesive layer 28 lifting up due to the foreign object.

[0173] A sheet of film, rubber, cloth, or the like may be sandwiched between the laminate 10 and the bag 106 and then vacuum-heat-compressed. By sandwiching the sheet and then vacuum-heat-compressing, it is possible to suppress indentations caused by dust that has become mixed in between the laminate 10 and the bag 106 being pressed against the laminate 10. Furthermore, if the slipperiness between the laminate 10 and the bag 106 is poor, uneven deaeration can be reduced by sandwiching a sheet with good slipperiness between both the laminate 10 and the bag 106.

[0174] The material of the above-mentioned film is not particularly limited, but examples thereof include acrylic resin films, polycarbonate (PC) resin films, cellulose ester resin films such as triacetyl cellulose (TAC) resin films, polyethylene terephthalate (PET) resin films, polyolefin resin films, polyester resin films, and acrylonitrile-butadiene-styrene copolymer films, and from the viewpoint of heat resistance, polycarbonate resin films, cellulose ester resin films, and polyethylene terephthalate resin films are preferred.

[0175] The film may have a surface irregularity from the viewpoint of improving the slipperiness. The surface irregularity can be imparted by a known method such as adding a matting agent to the film or embossing the film.

[0176] The surface of the film is preferably subjected to an antistatic treatment in order to reduce adhesion of foreign matter during vacuum thermocompression bonding. The antistatic treatment can be carried out by a known method such as adding an antistatic agent.

[0177] The rubber is not particularly limited in terms of material, but examples thereof include butadiene rubber (BR), styrene-butadiene rubber (SBR), chloroprene rubber (CR), isoprene rubber (IR), acrylonitrile-butadiene rubber (NBR), ethylene-propylene-diene rubber (EPDM), butyl rubber (IIR), silicone rubber, and fluororubber, with EPDM rubber, silicone rubber, and fluororubber being preferred from the viewpoint of heat resistance. These may be used alone or in combination of two or more.

[0178] The rubber may have an uneven surface from the viewpoint of improving the slipperiness. The uneven surface can be imparted by a known method such as adding a matting agent to the rubber or embossing the rubber.

[0179] The rubber is preferably subjected to an antistatic treatment on its surface in order to reduce adhesion of foreign matter during vacuum heat and pressure bonding. The antistatic treatment can be performed by a known method such as adding an antistatic agent.

[0180] The rubber may be formed into a film by a known method, or a commercially available product may be used. Commercially available rubbers include EB240N, EB250N, EB260N, EB270N, EB280W, EB265N, EB565N, and EB360E2 (all EPDM rubbers, manufactured by Maxell Kureha Co., Ltd.), SW940D, SW950D, SW960D, SW970D, SR950D, SR930T, SR940T, SH950T, and SW955T (all silicone rubbers, manufactured by Maxell Kureha Co., Ltd.), and FB750N, FB760N, FB770N, FB780N, FB880N, and FB970N (fluororubbers, manufactured by Maxell Kureha Co., Ltd.).

[0181] The cloth is preferably made of a dust-free material in order to reduce the generation and adhesion of foreign matter during vacuum heat pressing, and is preferably sewn with conductive carbon yarn in order to prevent static electricity.

[0182] The fabric may be prepared by a known method, or a commercially available product such as HM-CLC (manufactured by Tanimura Co., Ltd.) may be used.

[0183] The above-mentioned film, rubber, cloth, etc. are preferably the same size as or larger than the laminate 10 so that the pressure from the bag 106 can be transmitted to the laminate 10 evenly.

[0184] The above-mentioned film, rubber, cloth, etc. may be the same size as the windshield glass 28 or may be larger in size.

[0185] The conditions for vacuum thermocompression bonding, such as the degree of vacuum and heating temperature, may be set appropriately depending on the material forming the adhesive layer 26, the heat resistance of the other materials forming the laminate 10, the thickness of the laminate 10, etc.

[0186] After the vacuum heat-pressing is completed, the laminate 10 and the windshield glass 28 are removed from the bag, and the laminate 10 and the windshield glass 28 are further heat-pressed in an autoclave in the same manner as before, as shown in the third row of Figure 2. During this heat and pressure bonding in an autoclave, adhesive layer 26 softens, and the softened adhesive layer 26 has a sufficient thickness of more than 100 μm, which allows foreign matter to be more suitably wrapped and embedded in adhesive layer 26. As a result, in the bonded body, lifting of adhesive layer 26 due to foreign matter can be more suitably prevented, and bubble-like defects caused by this lifting can be further significantly reduced. After the heat-pressure bonding in the autoclave is completed, the laminated body is removed from the autoclave and cooled, as shown in the lower part of FIG. As described above, after the heat and pressure bonding in the autoclave is completed, the protective film 12 may be peeled off.

[0187] Here, the laminate 10 of the present invention has an oxygen permeability coefficient of the transparent resin layer 16 of 300 cc / m 2 ·day·atm or less is preferable. The oxygen permeability coefficient of the transparent resin layer 16 is 300 cc / m 2 By setting the pressure to 1000 kJ / day atm or less, the bubble defects can be more suitably eliminated by heating and pressurizing in the autoclave, as shown in the lower part of FIG.

[0188] The conditions of the autoclave, such as the pressure and heating temperature, may be set appropriately depending on the material forming the adhesive layer 26, the heat resistance of the other materials forming the laminate 10, the thickness of the laminate 10, and the like.

[0189] The image display system of the present invention comprises the laminate of the present invention and an image display device that projects an image onto the laminate of the present invention. An example in which the image display system of the present invention is used in a head-up display system is conceptually shown in Figure 4. In the following description, the head-up display system is also referred to as HUD.

[0190] The HUD 30 shown in FIG. 4 includes a laminate 10A of the present invention and a projector 32. As conceptually shown in FIG. 5, the laminate 10A is attached to a windshield glass 28 with the adhesive layer 26 facing the windshield glass 28 side. The laminate 10A is obtained by laminating the laminate 10 shown in FIG. 1 to a windshield glass 28 and then peeling off the protective film 12.

[0191] The projector 32 shown in FIG. 4 includes an image forming section 34, an intermediate image screen 36, a mirror 38, and a concave mirror 40.

[0192] In the HUD 30 shown in Figure 4, the projection light projected by the projector 32 passes through a transparent window 46 provided on the dashboard 42 of the vehicle in which the HUD 30 is mounted, as shown by the dashed line, enters the laminate 10A attached to the windshield glass 28, is reflected by the reflective layer 20, and is observed by the driver D (dashed line). As with known HUDs, in the illustrated HUD 30, the driver D observes a virtual image of an image projected onto the windshield glass .

[0193] The image forming unit 34 includes an LCD 50 (Liquid Crystal Display) and a projection lens 52 . The LCD 50 and the projection lens 52 are both well-known components used in projectors for HUDs. The image forming unit 34 projects the image displayed by the LCD 50 onto the intermediate image screen 36 using the projection lens 52. In the projector 32, the projected image is converted into a real image by the intermediate image screen 36, and this real image is reflected along a predetermined optical path by the mirror 38 and the concave mirror 40. As described above, this reflected light passes through the transparent window 46 provided in the dashboard 42, enters the laminated body 10A, and is reflected, and the projected image is observed by the driver D.

[0194] In a preferred embodiment, the LCD 50 displays a p-polarized image (projected image). That is, in a preferred embodiment, the HUD 30 of the present invention has the projector 32 irradiate p-polarized projection light. Therefore, if the LCD 50 does not display p-polarized projected light, it is preferable to provide a polarizer that converts the projected light from the LCD 50 to p-polarized light, for example, somewhere along the optical path of the projected light from the LCD 50 to the concave mirror 40. Any known polarizer can be used. Alternatively, a polarizer that converts the projected light from the LCD 50 into p-polarized light may be provided outside the projector 32, that is, somewhere along the optical path of the projected light from the concave mirror 40 to the windshield glass .

[0195] The illustrated laminate 10A uses a cholesteric liquid crystal layer as the reflective layer 20, for example. In the illustrated laminate 10A, the retardation layer 18 is, for example, a quarter-wave plate, which converts incident p-polarized light into circularly polarized light in the rotation direction that is selectively reflected by the reflective layer 20, i.e., the cholesteric liquid crystal layer. Therefore, the laminate 10A converts p-polarized light into circularly polarized light by the retardation layer 18, reflects this circularly polarized light by the reflective layer 20, and converts the circularly polarized light back into p-polarized light by the retardation layer 18. In this way, the laminate 10A selectively reflects p-polarized light. As is well known, polarized sunglasses selectively block s-polarized light. Therefore, by emitting p-polarized projection light from projector 32, a p-polarized projection image can be projected, and even if driver D is wearing polarized sunglasses, the image projected by HUD 30 can be observed.

[0196] In the projector that constitutes the HUD of the present invention, the image forming unit 34 is not limited to one that uses the LCD 50, and various known image forming means that are used in HUD projectors can be used. For example, various known image forming means used in HUD projectors (imagers) can be used, such as a fluorescent display tube, an LCOS (Liquid Crystal on Silicon) display using liquid crystal, an organic electroluminescence (organic EL) display, and a DLP (Digital Light Processing) display using a DMD (Digital Micromirror Device). In these image forming means, like the LCD 50, a projection image is projected onto the intermediate image screen 36 by a projection lens. As the image forming means of the image forming unit 34, an image forming means by light beam scanning (light beam scanning) can also be used.

[0197] The projection light emitted from the image forming unit 34 is then formed into a real image (visible image) by the intermediate image screen 36. There are no limitations on the intermediate image screen 36, and various known intermediate image screens that convert the projected image into a real image in a HUD projector can be used. Specifically, examples of the intermediate image screen 36 include a scattering film, a microlens array, and a screen for rear projection.

[0198] As described above, the projected light that has been formed into a real image on the intermediate image screen 36 is reflected along a predetermined optical path by the mirror 38 and the concave mirror 40, passes through the transparent window 46 provided in the dashboard 42, and is projected onto the laminate 10A bonded to the windshield glass 28, where it is observed by the driver D (see the dotted line).

[0199] Mirror 38 is a known mirror used in a projector to adjust the optical path of projection light. Mirror 38 may also be a so-called cold mirror that reflects visible light and transmits infrared light, thereby preventing heating of components of projector 32 due to sunlight entering through the windshield glass. On the other hand, the concave mirror 40 is a known concave mirror that enlarges and projects projection light and is used in a projector for an HUD.

[0200] Although the projector 32 in the illustrated example uses the mirror 38 and the concave mirror 40 as components for changing the optical path of the projection light, the present invention is not limited to this. For example, projector 32 may have only one of mirror 38 and concave mirror 40, or may have one or more other light-reflecting elements, such as freeform mirrors, in addition to or instead of mirror 38 and / or concave mirror 40. That is, the projector that constitutes the HUD of the present invention can be configured using various types of light reflecting elements.

[0201] As described above, the projector 32 emits p-polarized projection light. The p-polarized projection light projected by the projector 32 and transmitted through the transmission window 46 is transmitted through the hard coat layer 14 and the transparent resin layer 16, and is incident on the retardation layer 18. As described above, the retardation layer 18 is a quarter-wave plate that converts the incident p-polarized projection light into circularly polarized light in the rotation direction that is selectively reflected by the reflective layer 20 (cholesteric liquid crystal layer). The circularly polarized projected light converted by the retardation layer 18 is reflected by the reflective layer 20, and enters the retardation layer 18 again, where it is converted by the retardation layer 18 back to the original p-polarized light. The projection light converted into p-polarized light by the polarization conversion layer 24 is irradiated onto the viewing position of the driver D. Here, since the projected image is p-polarized, as described above, the driver D can view the projected image properly even if he or she is wearing polarized sunglasses. Furthermore, as described above, in the laminate 10 of the present invention, the thickness of the adhesive layer 26 is greater than 100 μm. Therefore, even if a foreign object is present between the adhesive layer 26 and the windshield glass 28, the foreign object can be embedded in the adhesive layer 26, which has a sufficient thickness, and the air around the defect dissolves in the adhesive layer 26, eliminating the air bubbles, thereby suppressing bubble-like defects caused by the foreign object. Therefore, with the image display system of the present invention, high-quality projected images can be viewed with reduced reduction in visibility due to bubble-like defects, regardless of whether or not polarized sunglasses are worn.

[0202] On the other hand, when glare-causing s-polarized light, such as light reflected from puddles or the hood, enters from outside the vehicle, this s-polarized light passes through the windshield glass 28 and enters the laminate 10A, and then passes through the adhesive layer 26 and enters the polarization conversion layer 24. The s-polarized light incident on the polarization conversion layer 24 is converted into elliptically polarized light with a rotation direction corresponding to the s-polarized light, for example, by the helical structure of the liquid crystal compound in the polarization conversion layer 24.

[0203] The elliptically polarized light that has passed through the polarization conversion layer 24 then enters the reflective layer 20 . As described above, the reflective layer 20 is a cholesteric liquid crystal layer that selectively reflects circularly polarized light converted from p-polarized light by the retardation layer 18. Therefore, elliptically polarized light with a rotation direction corresponding to s-polarized light is transmitted through the reflective layer 20. Furthermore, by transmitting through the reflective layer 20 (cholesteric liquid crystal layer), the elliptically polarized light with a rotation direction corresponding to s-polarized light is converted into circularly polarized light with a rotation direction corresponding to s-polarized light. The circularly polarized light that has passed through the reflective layer 20 is incident on the retardation layer 18 . As described above, the retardation layer 18 is a quarter-wave plate that converts p-polarized light into circularly polarized light that is selectively reflected by the cholesteric liquid crystal layer that constitutes the reflective layer 20. Therefore, circularly polarized light with a rotation direction corresponding to s-polarized light that is incident on the retardation layer 18 is transmitted through the retardation layer 18 and converted into s-polarized light. In this way, s-polarized light that enters from outside the vehicle and causes glare passes through the laminate 10A as s-polarized light. Therefore, even when this s-polarized light reaches the driver D, it is blocked by polarized sunglasses. That is, when the laminate of the present invention is used in a HUD, it has a polarization conversion layer 24, which compensates for the change in polarization of external light caused by the retardation layer and reflective layer, allowing s-polarized light that enters from outside the vehicle and causes glare to pass through as s-polarized light, making it possible to block the light with polarized sunglasses. That is, polarized sunglasses are suitable for use in HUDs. In the present invention, when the retardation layer 18, the reflective layer 20, the polarization conversion layer 24, and the adhesive layer 26 are provided in this order, good results can be obtained in terms of suitability for polarized sunglasses and suppression of bubble-like defects caused by foreign matter.

[0204] The image display system of the present invention is not limited to the HUD shown in the figure. That is, the image display system of the present invention can be used in various known image display systems as long as it has the laminate of the present invention and an image display device that projects an image onto the laminate of the present invention.

[0205] The laminate, bonded body, and image display system of the present invention have been described in detail above, but the present invention is not limited to the above-described embodiments, and various improvements or modifications may be made within the scope of the present invention. [Example]

[0206] The features of the present invention will be explained in more detail below with reference to examples. The materials, reagents, amounts and proportions of substances, and procedures shown in the following examples can be changed as appropriate without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the following examples.

[0207] Example 1

[0208] <Preparation of composition for forming reflective layer, composition for forming retardation layer, and composition for forming polarization conversion layer> The components were mixed according to the formulations shown in Table 1 below and filtered through a polypropylene filter with a pore size of 10 μm to prepare compositions BG1, R1 and IR1 for forming a reflective layer, composition A1 for forming a retardation layer, and composition TW-1 for forming a polarization conversion layer. The blending amount of each component shown in Table 2 is expressed in parts by mass. The mixture 1, alignment control agent 1 and alignment control agent 2 are the following compounds.

[0209] [ka]

[0210] [ka]

[0211] [ka]

[0212] [Table 1]

[0213] <Preparation of Adhesive Layer-Forming Composition> The components were mixed according to the formulation shown in Table 2 below, and filtered through a polypropylene filter with a pore size of 10 μm to prepare adhesive layer-forming composition HS-1. The blending amount of each component shown in Table 2 is expressed in parts by mass.

[0214] [Table 2]

[0215] (Preparation of transparent resin layer) <Preparation of Transparent Resin Layer 1> A 40 μm thick cellulose acylate film was prepared using the same preparation method as in Example 20 of International Publication No. 2014 / 112575. UV-531 manufactured by Teisei Chemical Industry Co., Ltd. was added to the cellulose acylate film as an ultraviolet absorber. The amount added was 3 phr (per hundred resin). The prepared cellulose acylate film was passed through a dielectric heating roll at a temperature of 60°C to raise the surface temperature of the film to 40°C, and then an alkaline solution having the composition shown below was applied to one side of the film using a bar coater in an amount of 14 mL / m 2 The coating was applied to the sample and the sample was left to stand under a steam-type far-infrared heater (manufactured by Noritake Co., Ltd.) heated to 110°C for 10 seconds. Next, using the same bar coater, pure water was applied at 3 mL / m 2 Apply. Next, after repeating washing with water using a fountain coater and draining with an air knife three times, the film is allowed to stay in a drying zone at 70° C. for 5 seconds and dried to prepare a transparent resin layer 1.

[0216] ---------------------------------------------------------------------------------- Composition of alkaline solution ---------------------------------------------------------------------------------- Potassium hydroxide 4.7 parts by mass ·Water 15.7 parts by mass Isopropanol 64.8 parts by mass Surfactants (C 16 H 33 O(CH2CH2O) 10 H) 1.0 parts by mass Propylene glycol 14.9 parts by mass ----------------------------------------------------------------------------------

[0217] <Formation of alignment film> On the surface of the transparent resin layer 1 obtained above that had been treated with the alkaline solution, a coating solution for forming an alignment film having the composition shown below was applied at a rate of 24 mL / m using a wire bar coater. 2The coating is then dried with hot air at 100°C for 120 seconds to obtain an alignment film with a thickness of 0.5 μm.

[0218] ---------------------------------------------------------------------------------- Composition of coating solution for forming alignment film ---------------------------------------------------------------------------------- 28 parts by weight of the modified polyvinyl alcohol shown below Citric acid ester (AS3, manufactured by Sankyo Chemical Co., Ltd.) 1.2 parts by mass Photoinitiator (Irgacure 2959, manufactured by BASF) 0.84 parts by mass Glutaraldehyde 2.8 parts by mass ·Water 699 parts by mass Methanol 226 parts by mass ----------------------------------------------------------------------------------

[0219] (denatured polyvinyl alcohol) [ka]

[0220] <Production of reflective film> The alignment film prepared above is rubbed (rayon cloth, pressure: 0.1 kgf (0.98 N), rotation speed: 1000 rpm (revolutions per minute), conveying speed: 10 m / min, number of times: 1 round trip) in a direction rotated 45° clockwise from the long side direction of the transparent resin layer.

[0221] The composition IR1 for forming a reflective layer is applied to the surface of the alignment film rubbed as described above using a wire bar at room temperature so that the thickness of the dried film after drying is 0.4 μm, thereby obtaining a coating film. The coating is dried at room temperature for 30 seconds, then heated in an atmosphere of 85°C for 2 minutes. Then, in an environment with an oxygen concentration of 1000 ppm or less, the coating is heated at 60°C using a Fusion D bulb (90 mW / cm 2The coating film is irradiated with ultraviolet light using a lamp (illumination lamp) at an output of 60% for 6 to 12 seconds to fix the cholesteric liquid crystal phase, thereby obtaining a cholesteric liquid crystal layer IR1 having a thickness of 0.4 μm. Next, the same process is repeated using the composition for forming a reflective layer BG1 on the surface of the obtained cholesteric liquid crystal layer IR1 to form a cholesteric liquid crystal layer BG1 having a thickness of 0.84 μm. Next, the same process is repeated using the composition for forming a reflective layer R1 on the surface of the obtained cholesteric liquid crystal layer BG1 to form a cholesteric liquid crystal layer R1 having a thickness of 0.36 μm. In this way, a film A1 is obtained having a structure of R1 / BG1 / IR1 / transparent resin layer 1. When the transmission spectrum of film A1 is measured with a spectrophotometer (V-670 manufactured by JASCO Corporation), a transmission spectrum having selective reflection center wavelengths at 515 nm, 685 nm, and 775 nm is obtained.

[0222] <Formation of adhesive layer> The adhesive layer-forming composition HS-1 is applied to the surface of the above-mentioned cholesteric liquid crystal layer R1 using a wire bar so that the film thickness after drying is 110 μm, and then dried at 120°C for 1 minute to form a coating film. Then, under a nitrogen purge, an air-cooled metal halide lamp (manufactured by Eye Graphics Co., Ltd.) with a power of 160 W / cm and an oxygen concentration of approximately 0.1% by volume was used to illuminate the coating at an intensity of 150 mW / cm. 2 , irradiation amount 300mJ / cm 2 The coating film is cured by irradiating it with ultraviolet light to obtain an adhesive layer HS1, thereby producing a laminate of Example 1 having a structure of HS1 / R1 / BG1 / IR1 / transparent resin layer 1.

[0223] <Example 2> A laminate of Example 2 is produced in the same manner as in Example 1, except that HS1 is applied so that the thickness becomes 150 μm.

[0224] Example 3 A laminate having a structure of HS1 / R1 / BG1 / IR1 / transparent resin layer 1 is prepared in the same manner as in Example 1, except that HS1 is applied to a thickness of 1 μm. A 300 μm-thick HS2 (KRYSTALFLEXPE 399, manufactured by Huntsman, urethane resin) is laminated to the HS1 surface of the above laminate using a laminating machine with a release-treated roller to produce a laminate of Example 3 having a configuration of HS2 / HS1 / R1 / BG1 / IR1 / transparent resin layer 1. The lamination conditions are a roll temperature of 110°C, a linear pressure of 1.0 MPa, and a linear speed (lamination speed) of 1.0 m / min. In the laminate of Example 3, HS2 and HS1 form adhesive layers.

[0225] Example 4 A laminate of Example 4 having a structure of HS2 / HS1 / R1 / BG1 / IR1 / transparent resin layer 1 was prepared in the same manner as in Example 3, except that HS2 was made to a thickness of 620 μm (KRYSTALFLEXPE 399, manufactured by Huntsman, urethane resin). In the laminate of Example 4, HS2 and HS1 serve as adhesive layers.

[0226] <Example 5> A laminate of Example 5 having a structure of HS2 / HS1 / R1 / BG / IR1 / transparent resin layer 1 was prepared in the same manner as in Example 3, except that HS2 was made to a thickness of 1240 μm (KRYSTALFLEXPE 399, manufactured by Huntsman, urethane resin). In the laminate of Example 5, HS2 and HS1 serve as adhesive layers.

[0227] Example 6 A laminate of Example 6 having a structure of HS2 / HS1 / R1 / BG1 / IR1 / transparent resin layer 1 was prepared in the same manner as in Example 3, except that HS2 was made to a thickness of 1910 μm (KRYSTALFLEXPE 399, manufactured by Huntsman, urethane resin). In the laminate of Example 6, HS2 and HS1 serve as adhesive layers.

[0228] Example 7 In the same manner as in Example 3, HS2 layers with a thickness of 1,910 μm were attached four times to the HS2 side of the laminate of Example 6 to produce a laminate of Example 7 consisting of HS2 / HS2 / HS2 / HS2 / HS2 / HS1 / R1 / BG1 / IR1 / transparent resin layer 1. In the laminate of Example 7, all HS2 and HS1 layers are adhesive layers.

[0229] Example 8 A composition A1 for forming a retardation layer is applied to the rubbed alignment film surface using a wire bar, dried, and then cured under the conditions below. Except for this, a composition IR1 for forming a reflective layer is applied onto the cured retardation layer A1, and a laminate of Example 8 having a structure of HS2 / HS1 / R1 / BG1 / IR1 / A1 / transparent resin layer 1 is produced in the same manner as in Example 6. In the laminate of Example 8, HS2 and HS1 are adhesive layers.

[0230] <Curing conditions for retardation layer-forming composition A1> The retardation layer-forming composition A1 was applied and dried to obtain a coating film, which was then placed on a hot plate at 50°C and heated with an electrodeless lamp "D bulb" (60 mW / cm) manufactured by Fusion UV Systems in an environment with an oxygen concentration of 1000 ppm or less. 2 ) for 6 seconds to irradiate the coating with ultraviolet light, thereby forming a retardation layer. This results in a retardation layer having a thickness adjusted to provide a desired front retardation, i.e., a desired retardation. The retardation of the produced retardation layer at 550 nm was measured using AxoScan manufactured by Axometrics and found to be 126 nm.

[0231] Example 9 A laminate of Example 9 having a structure of HS2 / HS1 / TW1 / R1 / BG1 / IR1 / A1 / transparent resin layer 1 was prepared in the same manner as in Example 8, except that a polarization conversion layer TW1 was provided on top of the cholesteric liquid crystal layer R1 to a thickness of 1.5 μm. In the laminate of Example 9, HS2 and HS1 serve as adhesive layers. The polarization conversion layer TW1 was prepared by applying the polarization conversion layer-forming composition TW1 onto the cholesteric liquid crystal layer R1 at room temperature using a wire bar, drying the coating at room temperature for 30 seconds, and then heating it in an atmosphere of 85°C for 2 minutes. The layer was then heated in an environment with an oxygen concentration of 1000 ppm or less at 60°C using a Fusion D bulb (90 mW / cm). 2 The coating film is irradiated with ultraviolet light using a lamp (such as the one shown in FIG. 1) at 60% output for 6 to 12 seconds to form a polarization conversion layer.

[0232] Example 10 <Preparation of curable composition for forming hard coat layer (HC layer)> The components were mixed according to the formulation shown in Table 3 below and filtered through a polypropylene filter with a pore size of 10 μm to prepare a curable composition for forming an HC layer HC-1 (composition for forming an HC layer HC-1). The blending amount of each component shown in Table 3 is expressed in parts by mass.

[0233] [Table 3]

[0234] <Formation of hard coat layer> An HC layer-forming curable composition HC-1 is applied to the surface of the transparent resin layer 1 of the laminate of Example 9 opposite to the surface treated with the alkaline solution, and cured to form an HC1 layer with a thickness of 6 μm. Specifically, the coating and curing methods are as follows: HC-layer-forming curable composition HC-1 is applied at a conveying speed of 30 m / min by the die coating method using a slot die described in Example 1 of JP 2006-122889 A, and dried at an atmospheric temperature of 60°C for 60 seconds to obtain a coating film. Thereafter, the coating is further dried at an oxygen concentration of about 0.1% by volume under nitrogen purging at 160 W / cm. 2 An air-cooled metal halide lamp (manufactured by Eye Graphics) was used, and the illuminance on the coating was 150mW / cm 2 , irradiation amount 600mJ / cm 2The coating is cured by irradiating ultraviolet light of 1000 W at 1000 W to form an HC layer, thereby producing a laminate of Example 10 having a structure of HS2 / HS1 / TW1 / R1 / BG1 / IR1 / A1 / transparent resin layer 1 / HC1. In the laminate of Example 10, HS2 and HS1 are adhesive layers.

[0235] Example 11 (Protection film production) <Preparation of Protective Film 1> A 125 μm thick PET film (Lumirror T60, manufactured by Toray Industries, Inc.) was used as the base layer, and MF-58 (adhesive layer thickness 12 μm, manufactured by Tomoegawa Paper Co., Ltd.) was used as the adhesive layer. After peeling off the light release film of MF-58, the exposed adhesive layer was placed in contact with the surface of the PET film, and the two films were laminated together with a rubber roller under a load of 2 kg to produce Protect Film 1, which had a PET film / adhesive layer / heavy release film configuration.

[0236] After peeling off the heavy release film of the protect film 1, the exposed adhesive layer was attached to the HC layer side of HC1 of the laminate of Example 10 with a rubber roller under a load of 2 kg so that the surface was in contact, producing the laminate of Example 11 having a configuration of HS2 / HS1 / TW1 / R1 / BG1 / IR1 / A1 / transparent resin layer 1 / HC1 / adhesive layer / PET film (P1). In the laminate of Example 11, HS2 and HS1 are adhesive layers.

[0237] Example 12 A laminate of Example 12 is prepared in the same manner as in Example 1, except that HS1 is applied so that the thickness becomes 300 μm.

[0238] Example 13 A 300 μm thick HS2 (KRYSTALFLEXPE 399, manufactured by Huntsman, urethane resin) is bonded to the R1 surface of the laminate having the R1 / BG1 / IR1 / transparent resin layer 1 configuration produced in Example 1 using a laminator with a release-treated roller to produce a laminate of Example 13 having the HS2 / R1 / BG1 / IR1 / transparent resin layer 1 configuration. The lamination conditions are a roll temperature of 110°C, a linear pressure of 1.0 MPa, and a linear speed (lamination speed) of 1.0 m / min. In the laminate of Example 13, HS2 is the adhesive layer.

[0239] <Comparative Example 1> The adhesive layer-forming composition HS-1 is applied to the surface of the transparent resin layer 1 that has been treated with the alkaline solution using a wire bar so that the film thickness after drying is 100 μm, and then the film is dried at 120°C for 1 minute to form a coating film. After that, under nitrogen purging, the oxygen concentration was increased to 160 W / cm at approximately 0.1% by volume. 2 An air-cooled metal halide lamp (manufactured by Eye Graphics) was used, and the illuminance on the coating was 150mW / cm 2 , irradiation amount 300mJ / cm 2 The coating film is cured by irradiating it with ultraviolet light of 1000 kJ / cm 2 , thereby producing a laminate of Comparative Example 1 having a structure of HS1 / transparent resin layer 1.

[0240] <Measurement of adhesive layer thickness> The film thickness is measured by observing with an optical microscope according to the following method. The cross sections of the laminates of the examples and comparative examples are exposed by a conventional method using a microtome, and the exposed cross sections are observed using an optical microscope. In the cross-sectional observation, the laminate is divided into four equal parts in the width direction, and the thickness of the adhesive layer is determined as the arithmetic mean of the film thicknesses at three equal division points excluding both ends.

[0241] <Evaluation of projected image visibility> The visibility of the projected image was evaluated as follows: The laminates of the examples and comparative examples, each measuring 280 mm long and 280 mm wide, are placed on a flat glass plate measuring 300 mm wide and 300 mm long at the center of the glass substrate, with the surface on the adhesive layer side in contact with the glass substrate. This was placed in a rubber bag and the pressure was reduced to 10 kPa (0.1 atmospheres) using a vacuum pump. The temperature was then raised to 95°C under reduced pressure, held for 20 minutes, and then returned to room temperature and pressure. The laminate was then held in an autoclave (manufactured by Kurihara Seisakusho) at 130°C and 1.1 MPa (11 atmospheres) for 20 minutes, bonding the laminate and glass substrate with the adhesive layer to obtain a glass sample. For laminates with a protective film, the protective film was peeled off after autoclave treatment. Indoors, an imager (Apple iPad®) was installed on a horizontal floor, with the image projection angle adjusted and secured. The glass sample was placed on a pedestal so that the distance between the center of the glass sample (image display unit) and the center of the imager was 1.0 m. The glass sample was tilted so that the angle between the floor and the surface of the glass sample was 30°. From a distance of 1.0 m from the glass sample, the laminate side of the glass sample was visually observed so that the gray background simulating a road and the HUD display image were superimposed. The luminance LB of the gray background and the luminance LI of the white display on the imager were measured using a spectroradiometer (SR-3AR, Topcon Technohouse Corporation), and the LI / LB ratio was 3.0. The HUD display image used displayed characters in white, green, and red, and was evaluated according to the following criteria. Note that A is within the acceptable range. A: I was able to clearly read the white, green, and red letters. B: The letters were faint and I couldn't read them.

[0242] <Evaluation of bubble defects> The bubble defects were evaluated as follows: In an environment with a cleanliness level of 10,000, the laminates of the examples and comparative examples, each measuring 90 mm in length and 90 mm in width, are placed in the center of a flat glass plate, 100 mm in width and 100 mm in length, with the surface on the adhesive layer side as the contact surface. This is placed in a rubber bag and the pressure is reduced to 10 kPa (0.1 atmospheres) using a vacuum pump. The temperature is then increased to 95°C under reduced pressure, maintained for 20 minutes, and then temporarily returned to room temperature and pressure. The laminate is then maintained in an autoclave (manufactured by Kurihara Seisakusho) at 130°C and 1.1 MPa (11 atmospheres) for 20 minutes, bonding the laminate and glass substrate with the adhesive layer to obtain a glass sample. For laminates with a protective film, the protective film is peeled off after autoclave treatment. The center 5cm of the above glass sample 2 The parts are observed for bubble defects using an optical microscope and evaluated according to the following criteria, with A to D being the acceptable range. A: No bubble-like defects with a diameter of 100 μm or more exist B: 1 to 5 bubble-like defects with a diameter of 100 μm or more C: 6 to 15 bubble-like defects with a diameter of 100 μm or more D: 16 to 30 bubble-like defects with a diameter of 100 μm or more E: The number of bubble-like defects with a diameter of 100 μm or more is 31 or more

[0243] <Evaluation of bubble defects on polycarbonate> The laminate of Example 11 was also adhered onto polycarbonate, that is, this example is an example of a laminate in which a polycarbonate resin substrate is used as the laminated object. In a cleanliness environment of 10,000, a 90mm long x 90mm long laminate of each of the examples and comparative examples was placed in the center of a 100mm wide x 100mm long polycarbonate sheet (LEXAN 9030HO, manufactured by Sabic, thickness 3mm) with the adhesive layer surface in contact with the polycarbonate sheet. This was placed in a rubber bag and the pressure was reduced to 10 kPa (0.1 atmospheres) using a vacuum pump. The temperature was then raised to 95°C under reduced pressure, held for 20 minutes, and then returned to room temperature and pressure. The laminate was then held in an autoclave (manufactured by Kurihara Seisakusho) at 130°C and 1.1 MPa (11 atmospheres) for 20 minutes, bonding the laminate and polycarbonate sheet with the adhesive layer to obtain a polycarbonate sample. For laminates with a protective film, the protective film was peeled off after autoclave treatment. The center 5cm of the polycarbonate sample 2 The parts are observed with an optical microscope for bubble-like defects and evaluated according to the following criteria. A: No bubble-like defects with a diameter of 100 μm or more exist B: 1 to 5 bubble-like defects with a diameter of 100 μm or more C: 6 to 15 bubble-like defects with a diameter of 100 μm or more D: 16 to 30 bubble-like defects with a diameter of 100 μm or more E: The number of bubble-like defects with a diameter of 100 μm or more is 31 or more The laminate of Example 11 was evaluated as having bubble-like defects on the polycarbonate, with the result being A.

[0244] <Impact resistance evaluation> The impact resistance was evaluated as follows: For the glass samples of the examples and comparative examples prepared in the same manner as in the evaluation of projected image visibility, a steel ball having a mass of 260 g was dropped from a height of 4 m onto the surface of the glass sample bonded with the laminate 10 in an environment of 23°C temperature and 50% RH. The point of impact was within 40 mm from the center of the glass sample. After dropping, the glass sample is observed and evaluated according to the following criteria. A: The steel ball does not penetrate the glass. B: The steel ball penetrates the glass

[0245] <Evaluation of adhesion of adhesive layer in laminate> The evaluation of the adhesiveness of the adhesive layer in the laminate, that is, the evaluation of the resistance to peeling of the adhesive layer in the laminate, was carried out as follows. The laminates of the examples and comparative examples were subjected to a cross-cut test according to JIS K 5600-5-6. The adhesion of the adhesive layer in the laminate at this time is evaluated according to the following criteria. A: The adhesive layer peels off less than 20% of the area. B: The adhesive layer peels off over 20% of the area.

[0246] [Table 4]

[0247] As shown in the table above, a bonded body using the laminate of the present invention can reduce bubble defects between the glass plate (substrate) and the laminate. Furthermore, by making the adhesive layer thickness 150 μm or more, particularly by making the adhesive layer thickness 300 μm or more, it is possible to significantly reduce bubble defects between the glass plate (substrate) and the laminate. Furthermore, the laminate of the present invention having a reflective layer also provides good visibility of projected images when used in, for example, a HUD. From the above results, the effects of the present invention are clear. [Explanation of symbols]

[0248] 10, 10A, 100 laminate 12 Protective film 14 Hard coat layer 16 Transparent resin layer 18 Retardation layer 20 reflective layer 24 Polarization conversion layer 26 Adhesive layer 28 Windshield Glass 30 Head-up display system 32 Projectors 34 Image forming unit 36 Intermediate image screen 38 Mirror 40 Concave Mirror 42 Dashboard 46 Transparent window 50 LCD (liquid crystal display) 52 Projection lens 102 Attached object Type 104 106 bags D. Driver

Claims

1. A laminate comprising a reflective layer and an adhesive layer, wherein the thickness of the adhesive layer is greater than 100 μm.

2. The laminate according to claim 1 , further comprising a retardation layer.

3. The laminate of claim 1 further comprising a polarization conversion layer.

4. The laminate according to claim 1 , further comprising a hard coat layer.

5. The laminate according to claim 1 , comprising a hard coat layer, the reflective layer, a retardation layer, a polarization conversion layer, and the adhesive layer.

6. A laminate comprising glass and the laminate according to any one of claims 1 to 5 bonded to the glass.

7. A laminate comprising a polycarbonate layer and the laminate according to any one of claims 1 to 5 laminated to the polycarbonate layer.

8. A laminate comprising a windshield glass and the laminate according to any one of claims 1 to 5 attached to the windshield glass.

9. An image display system comprising: the laminate according to any one of claims 1 to 5; and an image display device that projects an image onto the laminate.

Images