Classifications

• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/30—Polarising elements
  • G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
  • G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B23/00—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose
  • B32B23/04—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose comprising such cellulosic plastic substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B23/046—Layered products comprising a layer of cellulosic plastic substances, i.e. substances obtained by chemical modification of cellulose, e.g. cellulose ethers, cellulose esters, viscose comprising such cellulosic plastic substance as the main or only constituent of a layer, which is next to another layer of the same or of a different material of natural rubber or synthetic rubber
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/06—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material
  • B32B27/08—Layered products comprising a layer of synthetic resin as the main or only constituent of a layer, which is next to another layer of the same or of a different material of synthetic resin
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
  • B32B27/306—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers comprising vinyl acetate or vinyl alcohol (co)polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/34—Layered products comprising a layer of synthetic resin comprising polyamides
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/36—Layered products comprising a layer of synthetic resin comprising polyesters
  • B32B27/365—Layered products comprising a layer of synthetic resin comprising polyesters comprising polycarbonates
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
  • B32B7/02—Physical, chemical or physicochemical properties
  • B32B7/023—Optical properties
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B7/00—Layered products characterised by the relation between layers; Layered products characterised by the relative orientation of features between layers, or by the relative values of a measurable parameter between layers, i.e. products comprising layers having different physical, chemical or physicochemical properties; Layered products characterised by the interconnection of layers
  • B32B7/04—Interconnection of layers
  • B32B7/12—Interconnection of layers using interposed adhesives or interposed materials with bonding properties
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B1/00—Optical elements characterised by the material of which they are made; Optical coatings for optical elements
  • G02B1/10—Optical coatings produced by application to, or surface treatment of, optical elements
  • G02B1/14—Protective coatings, e.g. hard coatings
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B5/00—Optical elements other than lenses
  • G02B5/30—Polarising elements
  • G02B5/3025—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state
  • G02B5/3033—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid
  • G02B5/3041—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks
  • G02B5/305—Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state in the form of a thin sheet or foil, e.g. Polaroid comprising multiple thin layers, e.g. multilayer stacks including organic materials, e.g. polymeric layers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2250/00—Layers arrangement
  • B32B2250/40—Symmetrical or sandwich layers, e.g. ABA, ABCBA, ABCCBA
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2307/00—Properties of the layers or laminate
  • B32B2307/40—Properties of the layers or laminate having particular optical properties
  • B32B2307/414—Translucent
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2307/00—Properties of the layers or laminate
  • B32B2307/70—Other properties
  • B32B2307/732—Dimensional properties
  • B32B2307/737—Dimensions, e.g. volume or area
  • B32B2307/7375—Linear, e.g. length, distance or width
  • B32B2307/7376—Thickness
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B2457/00—Electrical equipment
  • B32B2457/20—Displays, e.g. liquid crystal displays, plasma displays
• • G—PHYSICS
  • G02—OPTICS
  • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
  • G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
  • G02B27/01—Head-up displays
  • G02B27/0101—Head-up displays characterised by optical features

Definitions

• the present invention relates to a translucent resin sheet, a projection display, and a moving body.
• head-up display devices have been known as projection-type displays that are mounted on moving objects such as automobiles (see, for example, Patent Document 1).
• the head-up display device described in Patent Document 1 reflects a display image displayed on a display device (display unit) such as a liquid crystal display or CRT with a mirror, and uses a windshield as a screen that is provided in a vehicle and has a curved surface shape.
• a display device display unit
• This is a device that obtains a virtual image by projecting it onto the image.
• a housing that accommodates the display section is provided within the dashboard, and the housing is formed with an exit window that outputs a display image.
• the exit window is provided with a polarizing layer composed of a polarizer that generates polarized light, and a protective layer mainly composed of a resin material, which is laminated on both sides of the polarizing layer. It has been proposed to arrange (install) a cover member (transparent resin sheet) (for example, see Patent Document 2).
• the light-transmitting cover member having such a configuration is punched out in accordance with the shape of the exit window provided in the housing, and then curved so that a recess is formed in the center. It is installed.
• the head-up display device having such a configuration is provided within the dashboard. Therefore, especially in the summer when the dashboard is exposed to high temperatures, the translucent cover member discolors, and as a result, the projected image (virtual image) formed on the screen (windshield) There was a problem in that the color tone was projected onto the screen as a different color tone.
• the purpose of the present invention is to accurately suppress or prevent the occurrence of cracks even when punched into a predetermined shape or even when deformed into a curved shape, and even when exposed to high temperatures. It is an object of the present invention to provide a translucent resin sheet whose discoloration is accurately suppressed or prevented, and a highly reliable projection display and moving body equipped with such a translucent resin sheet.
• A/B (1) of the product of the content rate A and the total thickness B when the translucent resin sheet is stored for 23 hours at a temperature of 25° C. and a humidity of 50% Rh (1) [ mm ⁇ %] satisfies the relationship: 0.20 ⁇ A ⁇ B(1) ⁇ 0.70.
• the protective layer is a single layer mainly composed of the resin material, The translucent resin sheet according to any one of (1) to (3) above, wherein the resin material is a polycarbonate resin.
• the light-transmitting resin sheet has the light-transmitting property according to any one of (1) to (8) above, and is used as the light-transmitting cover member that transmits light emitted from a projection type display. resin sheet.
• a projection type display comprising the translucent resin sheet described in (9) above as the translucent cover member.
• a moving object comprising the projection display according to (10) above.
• a translucent resin sheet that includes a polarizing layer made of a polarizer and protective layers mainly made of a resin material and provided on both sides of the polarizing layer.
• the moisture content in the translucent resin sheet is defined as A [%]
• the total thickness of the two protective layers provided on both sides of the polarizing layer is defined as B [mm].
• a translucent cover member that transmits the light emitted from the projection display a translucent resin sheet is punched out in accordance with the shape of the exit window provided in the housing of the projection display, and Even if the transparent resin sheet is attached in a curved state corresponding to the exit window, it is possible to accurately suppress or prevent the occurrence of cracks in the transparent resin sheet (transparent cover member). Furthermore, even if the projection display is exposed to high temperatures such as on a dashboard in the summer, discoloration of the translucent resin sheet (transparent cover member) can be accurately suppressed or prevented. Therefore, the emitted light that has passed through the translucent cover member can be reliably projected onto the screen in the designed color tone.
• FIG. 1 is a side view showing an embodiment of a head-up display device for an automobile, which has a translucent resin sheet of the present invention as a translucent cover member.
• FIG. 2 is an enlarged cross-sectional view of the region [A] surrounded by the dashed line in FIG.
• FIG. 3 is an enlarged sectional view of the translucent resin sheet of the present invention applied to the translucent cover member in FIG. 2.
• the head-up display device projection type display
• the translucent resin sheet of the present invention as a translucent cover member.
• FIG. 1 is a side view showing an embodiment of a head-up display device for an automobile having a translucent resin sheet of the present invention as a translucent cover member
• FIG. FIG. 3 is an enlarged sectional view of the region [A]
• FIG. 3 is an enlarged sectional view of the translucent resin sheet of the present invention applied to the translucent cover member in FIG.
• the upper side in FIGS. 1 to 3 will be referred to as “upper” or “upper”
• the lower side will be referred to as “lower” or “lower”.
• the left side in FIGS. 1 and 2 is referred to as the "front” or “front”
• the right side is referred to as the "rear” or “rear”.
• the translucent cover member is illustrated in a flat state, and the thickness direction is exaggerated and schematically illustrated.
• the head-up display device 10 includes a display section 11, a reflective member 12, and a storage body 13.
• the display unit 11 is configured with a liquid crystal display, and emits the display image LS as emitted light, and displays red (R), green (G), and blue ( B)
• a full-color display image LS is formed by emitting light of each color from the display section 11.
• the reflecting member 12 is made of, for example, a mirror, and can reflect the display image LS from the display section 11.
• the display image LS reflected by the reflective member 12 is projected onto the back surface 102a (inner surface) of the windshield 102 using the windshield 102 as a screen. This projected light is then recognized by the driver H as a display image LS (see FIGS. 1 and 2).
• the storage body 13 (housing) has a box shape, and the display section 11, the reflective member 12, and other components constituting the head-up display device 10 are stored inside the storage body 13 (housing). Further, the storage body 13 has a window portion 131 that is an opening that opens toward the windshield 102 side. Via this window portion 131, the display image LS is emitted as emitted light toward the outside of the storage body 13, that is, toward the windshield 102.
• the light-transmitting cover member 1 having a light-transmitting property is curved so that a concave portion is formed in the center and the side of the storage body 13 is convex and the side of the windshield 102 is concave. It is installed (installed) so as to cover the window portion 131 in the curved state.
• This allows the display image LS to be emitted toward the windshield 102, and also prevents foreign matter such as dust from entering the storage body 13 through the window portion 131. Therefore, it is possible to prevent the display image LS of the display unit 11 and the reflective member 12 from becoming cloudy or dirty due to the foreign matter.
• the translucent cover member 1 easily reflects sunlight, and it is possible to accurately prevent sunlight from entering the storage body 13 . Further, for example, the translucent cover member 1 can be prevented from protruding from the dashboard 101, and therefore the translucent cover member 1 can be prevented from blocking the driver's H's view.
• the translucent cover member 1 is made of a translucent resin sheet of the present invention that can transmit light, and includes a polarizing layer 2 made of a polarizer that generates polarized light of the light, and a polarizing layer 2 made of a polarizer that generates polarized light of the light.
• Protective layers 3A and 3B are provided on both sides of the layer 2 and are mainly made of a resin material.
• the moisture content (moisture percentage) in the translucent resin sheet (transparent cover member 1) is A [%]
• the total thickness of the protective layers 3A and 3B is B [mm].
• the light-transmitting cover member 1 can be used as a head-up display device 10 (projection type display).
• a translucent resin sheet is punched out corresponding to the shape of the window portion 131 (exit window) provided in the storage body 13 (housing).
• the generation of cracks in the transparent cover member 1 can be accurately suppressed or It can be prevented.
• the dashboard 101 is exposed to high temperatures in the summer, the head-up display device 10 provided within the dashboard 101 is also exposed to high temperatures.
• the display image LS emitted light
• the display unit 11 can be reliably projected onto the back surface 102a of the windshield 102 as a screen in the designed color tone.
• the translucent cover member 1 is capable of transmitting light, and in this embodiment, it includes a polarizing layer 2, a bonding layer 4A and a bonding layer 4B, a protective layer 3A and a protective layer. 3B. Each layer will be explained below.
• the polarizing layer 2 is an intermediate layer located at the center in the thickness direction of the transparent cover member 1 (transparent resin sheet), and its thickness is constant in the surface direction of the transparent cover member 1. be.
• This polarizing layer 2 has a function as a polarizer that extracts linearly polarized light having a polarization plane in one predetermined direction from the light passing through the transparent cover member 1. Thereby, the light passing through the translucent cover member 1 is polarized.
• the degree of polarization of the polarizing layer 2 is as close to 100% as possible, and specifically, it is preferably 80.0% to 98.0%, and 85.0% to 98.0%. % or more and 98.0% or less is more preferable. This allows the polarizing layer 2 to reliably function as a polarizer.
• Such a polarizing layer 2 is not particularly limited as long as it has the above-mentioned functions, but examples include polyvinyl alcohol (PVA), partially formalized polyvinyl alcohol, polyethylene vinyl alcohol, polyvinyl butyral, polycarbonate, and ethylene-vinyl acetate.
• PVA polyvinyl alcohol
• a polymer film made of a partially saponified polymer is adsorbed with a dichroic substance such as iodine or a dichroic dye, and then uniaxially stretched, a dehydrated product of polyvinyl alcohol, or a film made of polyvinyl chloride.
• Examples include polyene-based oriented films such as those treated with dehydrochloric acid.
• the polarizing layer 2 is preferably a film obtained by adsorbing iodine or a dichroic dye to a polymer film mainly made of polyvinyl alcohol (PVA), dyeing the film, and then uniaxially stretching the film.
• PVA polyvinyl alcohol
• Polyvinyl alcohol (PVA) is a material that is excellent in transparency, heat resistance, affinity with iodine or dichroic dyes as dyeing agents, and orientation during stretching. Therefore, the polarizing layer 2 mainly made of PVA has excellent heat resistance and polarizing ability.
• dichroic dyes include, but are not particularly limited to, Brilliant Blue 6B, Sorophenyl Blue FGLE220%, Sorophenyl Blue GL250%, Kayaseron Blue C-2R, Chlorazole Black BH, Direct Paper Blue STL, Solarus.
• main material refers to a constituent material containing 50% by weight or more of the constituent materials constituting the layer containing this material.
• the thickness of the polarizing layer 2 is not particularly limited, and is preferably, for example, 5 ⁇ m or more and 60 ⁇ m or less, more preferably 10 ⁇ m or more and 40 ⁇ m or less. If the thickness is less than the lower limit, the polarizing layer 2 may not be able to function as a polarizer sufficiently, and even if the thickness exceeds the upper limit, the polarizing layer 2 may not function as a polarizer any further. I can't hope for that.
• the refractive index of the polarizing layer 2 is not particularly limited, and is preferably, for example, 1.50 or more and 1.60 or less, and more preferably 1.52 or more and 1.55 or less.
• a protective layer 3A is arranged on the upper surface side of the polarizing layer 2, and a protective layer 3B is arranged on the lower surface side, thereby protecting the polarizing layer 2 and protecting the polarizing layer 2. It functions as a water vapor barrier layer that prevents water vapor (moisture) from reaching 2.
• These protective layers 3A and 3B are composed of a single layer body mainly made of a resin material such as, but not limited to, polyamide resin, polycarbonate resin, and cellulose resin such as triacetyl cellulose.
• a resin material such as, but not limited to, polyamide resin, polycarbonate resin, and cellulose resin such as triacetyl cellulose.
• polyamide resin or polycarbonate resin it is preferable to use polyamide resin or polycarbonate resin as the main material, and it is more preferable to use polycarbonate resin as the main material.
• the polycarbonate resin is rich in mechanical strength such as transparency (translucent property) and rigidity, it is possible to improve the transparency and impact resistance of the translucent cover member 1. Furthermore, among the resin materials, polycarbonate resins, polyamide resins, and cellulose resins are superior in water vapor barrier properties in that order, and polycarbonate resins can be said to be particularly excellent resin materials in water vapor barrier properties.
• a translucent cover member 1 that satisfies the relationship 0.20 ⁇ A ⁇ B(1) ⁇ 0.70 can be obtained relatively easily.
• the polyamide resin is not particularly limited, and various resins can be used, such as alicyclic polyamide, semi-aromatic polyamide, and the like.
• Alicyclic polyamide is a material with excellent impact resistance. Therefore, the transparent cover member 1 can exhibit excellent impact resistance.
• semi-aromatic polyamide is a material with high elastic modulus. Therefore, the translucent cover member 1 can have excellent resistance to stress such as bending.
• semi-aromatic polyamide refers to a polyamide in which one of dicarboxylic acid and diamine as monomers constituting the polyamide is an aromatic compound and the other is an aliphatic compound, Specifically, it can be represented by the following formula (1B).
• R 1 and R 2 are divalent aromatic substituent and the other is a divalent aliphatic substituent, and n is an integer of 2 or more.
• the polyamide may be a copolymer (random copolymer, block copolymer, etc.) containing two or more types of monomers for at least one of dicarboxylic acid and diamine.
• aromatic substituent among R 1 and R 2 in the above formula (1B) is preferably a group represented by the following formula (2B).
• l and m are each independently an integer of 0 or more and 2 or less.
• the polarizing layer 2 can be more suitably protected, and the processability of the translucent cover member 1 can be further improved.
• the retardation can be more easily controlled by stretching the protective layers 3A and 3B.
• the aliphatic substituent among R 1 and R 2 in the above formula (1B) is preferably a group having 4 to 18 carbon atoms, and preferably a hydrocarbon group having 4 to 18 carbon atoms. is more preferable, and even more preferably a saturated hydrocarbon group having 4 or more and 18 or less carbon atoms. Thereby, the workability of the translucent cover member 1 can be further improved.
• the semi-aromatic polyamide is preferably a compound containing an aromatic dicarboxylic acid and an aliphatic diamine as constituent monomers.
• the polarizing layer 2 can be more suitably protected, and the processability of the light-transmitting cover member 1 can be further improved. Furthermore, retardation due to stretching can be more easily controlled.
• Alicyclic polyamide has an alicyclic chemical structure in its molecule, and may have an alicyclic chemical structure in its main chain structure, or an alicyclic chemical structure in its side chain structure. It may have the chemical structure.
• alicyclic polyamide examples include compounds in which at least one of dicarboxylic acid and diamine as monomers constituting the polyamide has an alicyclic chemical structure, and specifically, for example, the following formula: (3B).
• R 3 and R 4 are each independently a hydrogen atom or a hydrocarbon group having 4 or less carbon atoms, o is an integer of 2 or more and 14 or less, and p is 0 or more and 6 or less n is an integer of 2 or more.
• the polycarbonate resin is not particularly limited, and various resins can be used, but aromatic polycarbonate resins are particularly preferred.
• the aromatic polycarbonate resin has an aromatic ring in its main chain, thereby making it possible to further improve the strength of the translucent cover member 1.
• This aromatic polycarbonate resin is synthesized, for example, by interfacial polycondensation reaction between bisphenol and phosgene, transesterification reaction between bisphenol and diphenyl carbonate, and the like.
• bisphenol examples include bisphenol A and bisphenol (modified bisphenol) which is the origin of the repeating unit of polycarbonate shown in the following formula (1A).
• X is an alkyl group having 1 to 18 carbon atoms, an aromatic group, or a cycloaliphatic group
• Ra and Rb are each independently an alkyl group having 1 to 12 carbon atoms.
• m and n are each integers from 0 to 4, and p is the number of repeating units.
• bisphenol that is the origin of the repeating unit of the polycarbonate shown in the formula (1A) include 4,4'-(pentane-2,2-diyl)diphenol, 4,4'-( Pentane-3,3-diyl)diphenol, 4,4'-(butane-2,2-diyl)diphenol, 1,1'-(cyclohexanediyl)diphenol, 2-cyclohexyl-1,4-bis( 4-hydroxyphenyl)benzene, 2,3-biscyclohexyl-1,4-bis(4-hydroxyphenyl)benzene, 1,1'-bis(4-hydroxy-3-methylphenyl)cyclohexane, 2,2'- Examples include bis(4-hydroxy-3-methylphenyl)propane, and one or more of these may be used in combination.
• the main component is a bisphenol type polycarbonate resin having a skeleton derived from bisphenol.
• the translucent cover member 1 can exhibit even better strength.
• the protective layers 3A and 3B may contain other components in addition to the resin material contained as the main material.
• Such components are not particularly limited, but include, for example, resin materials other than the main material, colorants such as dyes, fillers, alignment aids, stabilizers (thermal stabilizers, ultraviolet absorbers, antioxidants, etc.) ), plasticizers, colorants, flame retardants, antistatic agents, and viscosity modifiers.
• the content of the resin material in the protective layers 3A, 3B is not particularly limited, but it is preferably 75 parts by mass or more, and preferably 85 parts by mass or more out of 100 parts by mass of the protective layers 3A, 3B. is more preferable.
• a translucent cover member 1 having excellent strength can be obtained.
• the constituent materials forming the protective layers 3A and 3B may be the same or different.
• the retardation of the protective layer 3A and the retardation of the protective layer 3B are preferably different, and the retardation of the protective layer 3A is preferably different.
• the retardation is lower than that of the protective layer 3B.
• the protective layer 3B is easily deformed in the direction in which the curvature becomes smaller due to thermal contraction, but the protective layer 3A can be made difficult to deform due to thermal contraction. Therefore, as shown in FIG. 2, by applying a translucent resin sheet to the translucent cover member 1 included in the head-up display device 10, the head-up display device 10 is used in a curved state. It is preferable to form a curved shape so that the protective layer 3B is located on the curved convex side and the protective layer 3A is located on the curved concave side. In this case, the protective layer 3B has a relatively high thermal shrinkage rate and is therefore relatively easily deformed by heat.
• the protective layer 3A has the function of suppressing the thermal deformation of the protective layer 3B. do. Therefore, the entire translucent cover member 1 can be prevented from being excessively deformed due to heat. As a result, it is possible to accurately suppress or prevent the translucent cover member 1 from being thermally deformed due to the dashboard 101 being exposed to high temperatures in the summer.
• the retardation of the protective layer 3A is preferably 0 nm or more and 500 nm or less, more preferably 50 nm or more and 350 nm or less.
• the retardation of the protective layer 3B is preferably 2,600 nm or more and 8,000 nm or less, more preferably 3,500 nm or more and 6,500 nm or less.
• the difference in retardation between the protective layers 3A and 3B can be achieved by varying the constituent materials contained in the layers, the thickness, and the stretching ratio.
• the stretching ratio of the protective layer 3A is not particularly limited, it is preferably set to the magnitude of the retardation, for example, from 0.95 to 1.1.
• the stretching ratio of the protective layer 3B is not particularly limited, but is preferably 1.5 or more and 3.5 or less so as to be set to the above-mentioned retardation.
• the stretching directions of the protective layer 3A, the protective layer 3B, and the polarizing layer 2 are the same. Thereby, the polarization performance of the translucent cover member 1 can be further improved.
• the thickness of the protective layers 3A and 3B is, for example, preferably 0.07 mm or more and 0.80 mm or less, more preferably 0.10 mm or more and 0.50 mm or less, and 0.12 mm or more and 0.35 mm or less. It is even more preferable to have one.
• the protective layers 3A, 3B can reliably exhibit the function of protecting the polarizing layer 2. Therefore, when the light-transmitting cover member 1 is mounted in a curved state to cover the window portion 131 of the storage body 13, the light-transmitting cover member 1 does not function as a cover member for covering the window portion 131. You can definitely make it work. Further, it is possible to obtain the translucent cover member 1 that satisfies the relationship 0.20 ⁇ A ⁇ B(1) ⁇ 0.70 relatively easily.
• the thicknesses of the protective layer 3A and the protective layer 3B may be different even if they match, as long as the transparent cover member 1 satisfies the relationship 0.20 ⁇ A ⁇ B(1) ⁇ 0.70. Good too.
• the refractive index of the protective layers 3A and 3B is not particularly limited, but is preferably, for example, 1.45 or more and 1.66 or less, and preferably 1.48 or more and 1.60 or less.
• the protective layers 3A and 3B are each composed of a single layer body mainly made of a resin material, but the present invention is not limited to this, and the protective layers 3A and 3B are For example, it may be constituted by a laminate having a first layer and a second layer mainly made of a resin material, the first layer and the second layer being joined by a bonding layer.
• the bonding layer 4A and the bonding layer 4B are various adhesives or pressure-sensitive adhesives such as urethane adhesive, epoxy adhesive, acrylic adhesive, and acrylic adhesive. Thereby, each layer can be reliably bonded to each other, and a translucent cover member 1 that can withstand long-term use can be obtained.
• the thickness of the bonding layers 4A and 4B is not particularly limited, and is preferably, for example, 0.005 mm or more and 0.04 mm or less, and more preferably 0.006 mm or more and 0.015 mm or less. If the thickness of the bonding layers 4A, 4B is less than the above-mentioned lower limit, the adhesive force may be reduced, and if the thickness of the bonding layers 4A, 4B exceeds the above-mentioned upper limit, the adhesive or pressure-sensitive adhesive Depending on the type, the translucent cover member 1 may be strained due to hardening and shrinkage of the bonding layers 4A and 4B. Furthermore, the thicknesses of the bonding layers 4A and 4B may be different, but are preferably the same.
• the refractive index of the bonding layers 4A and 4B is not particularly limited, and is preferably, for example, 1.46 or more and 1.55 or less, and more preferably 1.461 or more and 1.545 or less.
• the light-transmitting cover member 1 (light-transmitting resin sheet) having such a configuration has the following problems as described in the background art described above.
• the transparent cover member 1 transparent resin sheet
• the translucent cover member 1 is also heated in the same way, the transparent cover member 1 changes color, and as a result, the display image LS (projected image) formed on the back surface 102a of the windshield 102 as a screen has a color tone different from the designed color tone.
• the image is projected onto the back surface 102a.
• the present inventor conducted extensive studies and found that these problems are related to the amount of water contained in the translucent cover member 1, especially the polarizing layer 2. I've come to understand. More specifically, if the amount of water contained in the light-transmitting cover member 1 (polarizing layer 2) is too small, the cracks will occur in the light-transmitting cover member 1 (polarizing layer 2). It has been found that if the amount of water contained in 2) is too large, the above-mentioned discoloration occurs in the translucent cover member 1 when the translucent cover member 1 is exposed to high temperatures.
• the inventor found that the amount of water contained in the translucent cover member 1 (particularly the polarizing layer 2) over a long period of time It has been found that the amount is closely related to the moisture content of the translucent cover member 1 as a whole and the thickness of the protective layers 3A and 3B. Specifically, when the moisture content in the transparent cover member 1 (transparent resin sheet) is A [%] and the total thickness of the protective layers 3A and 3B is B [mm], the transparent Relational expression A and B of the product of the content rate A and the total thickness B when the optical cover member 1 (transparent resin sheet) is stored for 23 hours at a temperature of 25 ° C. and a humidity of 50% Rh (1) It has been discovered that the above problem can be solved by satisfying the relationship of 0.20 ⁇ A ⁇ B (1) ⁇ 0.70, and the present invention has been completed. Ta.
• the storage body 13 When punching out the translucent cover member 1 (translucent resin sheet) corresponding to the shape of the window 131 (output window) provided in When the light-transmitting cover member 1 is brought into a curved state, it is possible to accurately suppress or prevent cracks from occurring in the light-transmitting cover member 1.
• the head-up display device 10 provided within the dashboard 101 is also exposed to high temperatures.
• a ⁇ B(1) [mm ⁇ %] is A ⁇ B(1) ⁇ 0.70
• the head-up display device 10 transparent cover member 1
• the display image LS (emitted light) emitted from the display unit 11 can be reliably projected onto the back surface 102a of the windshield 102 as a screen in the designed color tone.
• the water vapor barrier to the polarizing layer 2 includes not only the thickness of the protective layers 3A and 3B laminated on the polarizing layer 2, but also the thickness of the bonding layers 4A and 4B. Although it is presumed that this is related to the bonding Excluding the thickness of layers 4A and 4B and setting the total thickness of protective layers 3A and 3B as B [mm], defining the magnitude of relational expression A and B (1) is the basis for parameter setting. This is considered to be a reasonable judgment.
• the relational expression A ⁇ B(1) [mm ⁇ %] only needs to satisfy the relationship 0.20 ⁇ A ⁇ B(1) ⁇ 0.70, but 0.23 ⁇ A ⁇ B(1) It is preferable to satisfy the relationship ⁇ 0.52, and more preferably to satisfy the relationship 0.23 ⁇ A ⁇ B(1) ⁇ 0.38.
• a and B(1) within the above range, the above effect can be exhibited more markedly.
• 0.42 ⁇ A ⁇ The relationship B(1) ⁇ 0.65 is preferable, and when the balance between the two is more considered, the relationship 0.46 ⁇ A ⁇ B(1) ⁇ 0.60 is more preferable.
• the product of the moisture content A and the total thickness B when the translucent cover member 1 is stored under different conditions such as a temperature of 35° C. and a humidity of 20% Rh for 22 hours is calculated.
• the relational expression A ⁇ B(2) [mm ⁇ %] preferably satisfies the following relationship: 0.10 ⁇ A ⁇ B(2) ⁇ 0.42, and 0.17 ⁇ A ⁇ B(2) ⁇ 0 More preferably, the relationship .30 is satisfied.
• the color change [ ⁇ E] of the translucent cover member 1 is based on the color value (L * a * b * ).
• the present invention is not limited thereto.
• each part constituting the projection display and the moving body of the present invention can be replaced with any structure that can perform the same function.
• PVA film Kuraray Vinylon #7500 (manufactured by Kuraray Co., Ltd.) was prepared as a PVA (polyvinyl alcohol) film.
• the protective film 1 is pressure-bonded as the protective layers 3A and 3B to both sides of the obtained polarizing layer 2 via a one-component moisture-curing polyurethane adhesive, resulting in a total thickness of 0.7 mm.
• a translucent resin sheet of Example 1 was produced.
• Example 2-5, 8, 9 Examples 2 to 5 and 8 were carried out in the same manner as in Example 1, except that in the step ⁇ 2>, the combination of protective films to be pressure-bonded as the protective layers 3A and 3B had the layer structure shown in Table 1. , 9 was obtained.
• Examples 6 and 7, Comparative Examples 1 and 2 were prepared in the same manner as in Example 1, except that the conditions for obtaining the polarizing layer 2 by drying were as shown in Table 1. , 2 was obtained.
• Example 10 A translucent resin sheet of Example 10 was obtained in the same manner as in Example 1 except that the drying of the polarizing layer 2 in step ⁇ 1> was omitted.
• the moisture content of the translucent resin sheet stored under these conditions was measured using a moisture content measuring device ("AQUATRACK 3E", manufactured by ITS Japan Co., Ltd.). The percentage (moisture content) A was measured.
• the size of A and B (1) was determined based on the obtained moisture content A and the total thickness B of the protective layers 3A and 3B included in the translucent resin sheet.
• the moisture content of the translucent resin sheet stored under these conditions was measured using a moisture content measuring device ("AQUATRACK 3E", manufactured by ITS Japan Co., Ltd.). The percentage (moisture content) A was measured.
• the size of A and B (2) was determined based on the obtained moisture content A and the total thickness B of the protective layers 3A and 3B included in the translucent resin sheet.
• the translucent resin sheet in each example has the relation that the relational expression A ⁇ B(1) [mm ⁇ %] is 0.20 ⁇ A ⁇ B(1) ⁇ 0.70. I was satisfied. As a result, even if the transparent resin sheet is formed into a curved shape, cracks can be accurately suppressed or prevented from occurring in the transparent resin sheet, and the transparent resin sheet can be The results showed that it was possible to accurately suppress or prevent the occurrence of discoloration in the translucent resin sheet even when exposed to.
• the relational expression A ⁇ B(1) [mm ⁇ %] was less than 0.20, and 0.20 ⁇ A ⁇ B(1) ⁇ 0. I was not satisfied with my 70-year relationship. The results showed that when a transparent resin sheet is formed into a curved shape, cracks occur in the transparent resin sheet.
• the relational expression A ⁇ B(1) [mm ⁇ %] exceeds 0.70, and the relationship 0.20 ⁇ A ⁇ B(1) ⁇ 0.70 is satisfied. This was not satisfactory, and as a result, when the translucent resin sheet was exposed to high temperatures, discoloration was observed in the translucent resin sheet.
• a translucent resin sheet that includes a polarizing layer made of a polarizer and protective layers mainly made of a resin material and provided on both sides of the polarizing layer.
• the moisture content in the translucent resin sheet is defined as A [%]
• the total thickness of the two protective layers provided on both sides of the polarizing layer is defined as B [mm].
• a translucent cover member that transmits the light emitted from the projection display a translucent resin sheet is punched out in accordance with the shape of the exit window provided in the housing of the projection display, and Even if the transparent resin sheet is attached in a curved state corresponding to the exit window, it is possible to accurately suppress or prevent the occurrence of cracks in the transparent resin sheet (transparent cover member). Furthermore, even if the projection display is exposed to high temperatures such as on a dashboard in the summer, discoloration of the translucent resin sheet (transparent cover member) can be accurately suppressed or prevented. Therefore, the emitted light that has passed through the translucent cover member can be reliably projected onto the screen in the designed color tone. Therefore, the present invention has industrial applicability.

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• 2023
  • 2023-06-29 CN CN202380050339.XA patent/CN119452280A/zh active Pending
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  • 2023-06-29 EP EP23831607.9A patent/EP4550014A4/en active Pending
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• 2025
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