Optical laminate, polarizing lens, and eyewear

Abstract

The present invention relates to an optical laminate (100, 110) which comprises a support (10), a polarizing element (20), and at least one adhesive layer (30) that is disposed between the support (10) and the polarizing element (20). The polarizing element (20) is a gray polyvinyl alcohol-based polarizing film in which hue values a*s and b*s in CIE 1976 L*a*b* color space are respectively in the range of - 5 to 5 inclusive. At least one adhesive layer (30) includes a plurality of hue adjustment dyes for adjusting the hue of the optical laminate (100, 110) and the transmittance of the visible light region, and the hue adjustment dyes include at least one of the following dyes (A) to (C). (A) A blue dye (which has a maximum absorption wavelength in a wavelength range of 600 nm to 700 nm inclusive), (B) a green dye (which has a maximum absorption wavelength in a wavelength range of 500 nm to 600 nm inclusive), and (C) a red dye (which has a maximum absorption wavelength in a wavelength range of 400 nm to 500 nm inclusive)

Description

Optical laminate, polarized lens and eyewear

[0001] The present invention relates to an optical laminate including a polarizing element, and to a polarized lens and eyewear (sunglasses, goggles, etc.) using the same.

[0002] Mirrored lenses are used in eyewear such as sunglasses and goggles to add fashion and anti-glare properties, and polarized lenses with polarizing properties are also used to provide even higher anti-glare properties.

[0003] The polarizing element used in a polarized lens generally comprises a polarizing film in which a dichroic dye such as iodine and / or an azo compound is adsorbed and oriented on a polyvinyl alcohol (PVA) film (in this case, it is also called a bare polarizing film). A polarizing plate is produced by laminating a transparent protective substrate (also called a support) to both sides of this polarizing element, and the polarizing plate is then bent to form a polarized lens. Furthermore, for the purpose of improving impact resistance or producing a vision correction lens, injection polarized lenses are also widely used, in which the bent plate is then lined with a polycarbonate resin or polyamide resin as a lens substrate by injection molding.

[0004] Polarizing elements are generally produced by a manufacturing method that includes dyeing and stretching processes. Furthermore, by changing the compounding ratio of the dichroic dye that is adsorbed and oriented in the PVA-based film to give eyewear a fashionable look, the color of the polarizing element can be adjusted to not only gray but also brown, ruby, green, and other colors.

[0005] Polarized sunglasses using such colored polarizing elements are generally designed with multiple dichroic dyes in the polarizing elements to achieve colors that cannot be adjusted with iodine-based dyes. These colored polarizing elements must be manufactured through a stretching process using a dyeing solution containing a dichroic dye for each color tone, which increases manufacturing costs. Furthermore, during the hot water test performed as a quality inspection after lens molding, the dyes in the colored polarizing elements may dissolve in water, potentially damaging the color of the polarizing elements.

[0006] In order to reduce this loss of color, Patent Document 1 describes the production of a colored polarizing element (polarizing film) with a polarization degree of less than 90% by combining a dye with dichroism with a dye with low dichroism or substantially no dichroism. By using not only a dye with dichroism but also a dye with low dichroism or substantially no dichroism, color change during heat bending processing is reduced.

[0007] International Publication No. 2014 / 115705

[0008] However, even in Patent Document 1, the need to manufacture polarizing films in each color tone increases the number of types of polarizing elements, resulting in an unresolved cost problem. Furthermore, if a large amount of water-soluble dye is added to a polarizing element to control transmittance, the dye may be removed from the polarizing element during a hot water test after lens molding, resulting in a color change. Furthermore, polarized sunglasses generally require optical properties with a polarization degree of 90% or more to provide high anti-glare properties, so a polarization degree of less than 90% may be considered insufficient. In particular, to increase the polarization degree of a polarizing element using a dye with low dichroism, the transmittance must, in principle, be reduced. Therefore, for polarizing elements for polarized sunglasses that use such dichroic dyes, although there is room for adjusting the hue by changing the dyeing conditions during the stretching process of the polarizing element, this requires significant changes to the processing conditions of the polarizing element or an increase in the number of polarizing elements, making it difficult to realize such polarized sunglasses.

[0009] Therefore, the present invention aims to provide an optical laminate for eyewear that includes polarizing elements, which allows for easier adjustment of hue and optical properties without increasing the number of types of polarizing elements, as well as polarized lenses and eyewear that use the same.

[0010] As a result of extensive research to solve the above-mentioned problems, the inventors discovered that an optical laminate for polarized sunglasses can be formed with any desired transmittance and color tone by using a gray polarizing element and incorporating multiple hue-adjusting dyes that adjust the hue into the adhesive layer in the optical laminate, and thus completed the present invention.

[0011] An optical laminate according to an embodiment of the present invention includes a support, a polarizing element, and at least one adhesive layer between the support and the polarizing element, ＊ a ＊ b ＊ Hue value a in color space ＊ s and b ＊ An optical laminate comprising a gray polyvinyl alcohol polarizing film in which each of s is in the range of -5 or more and 5 or less, at least one adhesive layer containing a plurality of hue-adjusting dyes that adjust the hue and transmittance in the visible light region of the optical laminate, the hue-adjusting dyes containing at least one of the following dyes (A) to (C): (A) a blue dye (having a maximum absorption wavelength in the wavelength region of 600 nm or more and 700 nm or less), (B) a green dye (having a maximum absorption wavelength in the wavelength region of 500 nm or more and 600 nm or less), and (C) a red dye (having a maximum absorption wavelength in the wavelength region of 400 nm or more and 500 nm or less).

[0012] In one embodiment of the present invention, the adhesive layer contains an amorphous polyester resin.

[0013] In one embodiment of the present invention, the polarizing element is a dye-based polarizing element having optical characteristics of a luminous-corrected single transmittance of 25% to 45% and a luminous-corrected polarization degree of 90% or more.

[0014] A polarized lens according to an embodiment of the present invention comprises a lens substrate and the above-described optical laminate, and a support on the viewing side of the optical laminate is formed by injection molding.

[0015] Eyewear according to an embodiment of the present invention includes the above-described polarized lens.

[0016] According to the present invention, it is possible to provide an optical laminate for eyewear that includes a polarizing element, which allows for easier adjustment of hue and optical properties without increasing the number of types of polarizing element, as well as polarized lenses and eyewear that use the same.

[0017] 1 is a schematic diagram showing an example of an embodiment of an optical laminate according to the present invention. 2 is a schematic diagram showing an example of another embodiment of an optical laminate according to the present invention. 3 is a schematic diagram showing an example of a shaping (bending) process of an optical laminate according to the present invention.

[0018] Hereinafter, embodiments according to the present invention will be described in detail. Note that the following embodiments are examples of some typical embodiments of the present invention, and various modifications can be made within the scope of the present invention. Furthermore, the term "adjustment" means that, based on the hue value, transmittance value, and waveform structure of the polarizing element used in the optical laminate, these values ​​are adjusted using a separate dye so that the desired hue value, transmittance value, and waveform structure are obtained when the optical laminate is produced.

[0019] The optical laminate of the present invention includes a support, a polarizing element, and at least one adhesive layer between the support and the polarizing element. ＊ a ＊ b ＊ Hue value a in color space ＊ s and b ＊ The polyvinyl alcohol polarizing film is gray, and each of s is in the range of -5 or more and 5 or less. At least one adhesive layer contains a plurality of hue-adjusting dyes that adjust the hue and transmittance in the visible light region of the optical laminate, and the hue-adjusting dyes include at least one of the following dyes (A) to (C): (A) a blue dye (having a maximum absorption wavelength in a wavelength region of 600 nm or more and 700 nm or less); (B) a green dye (having a maximum absorption wavelength in a wavelength region of 500 nm or more and 600 nm or less); and (C) a red dye (having a maximum absorption wavelength in a wavelength region of 400 nm or more and 500 nm or less).

[0020] This makes it possible to easily adjust the color of an optical laminate of any desired hue from a single type of polarizing element. Furthermore, by using an optical laminate having such a configuration, the color of the optical laminate can be adjusted by utilizing a post-process such as a coating process, without adding a stretching process for a polarizing element, which has low production efficiency. As a result, it is possible to provide an optical laminate, and polarized lenses and eyewear using the same, simply and at low cost.

[0021] Furthermore, because the hue-adjusting dyes can be easily mixed into the adhesive layer and incorporated into a layer contained in the optical laminate, polarized lenses can be provided that are less susceptible to changes in optical properties due to dye loss during lens polishing and other processes than when these dyes are incorporated into the resin that forms the lens substrate. Furthermore, because the dyes are contained only in the adhesive layer, a wide range of support materials can be used without being limited by the type of support. Because these dyes are poorly soluble in water, there is no risk of discoloration or discoloration even when exposed to water or high humidity, making it possible to provide highly reliable polarized lenses. Furthermore, because the hue of the polarized lens is adjusted in the adhesive layer containing these dyes, it does not directly affect the polarization degree of the polarizing element, and there is no need to individually redesign and manufacture the polarizing element to adjust the hue.

[0022] <Optical laminate> Fig. 1 shows one embodiment of an optical laminate according to the present invention. As shown in Fig. 1, the optical laminate 100 includes two supports 10, a polarizing element 20, and two adhesive layers 30 between each of the supports 10 and the polarizing element 20, which are arranged in the following order from the external light incident side: first support / adhesive layer / polarizing element / adhesive layer / second support. In other words, the polarizing element 20 is arranged so as to be interposed between the two supports (first support and second support) 10 via the respective adhesive layers 30.

[0023] 2, an optical laminate 110 optionally further includes a support 10, which is arranged in the following order from the external light incident side: first support / adhesive layer / polarizing element / adhesive layer / second support / adhesive layer / third support. That is, the optical laminate 110 includes three supports 10, a polarizing element 20, and three adhesive layers 30, with the polarizing element 20 interposed between the two supports (first support and second support) 10 via the respective adhesive layers 30. A further support (third support) 10 is provided on the opposite side (viewing side) from the external light incident side via an adhesive layer 30. In either embodiment, the first support is arranged on the external light incident side when the eyewear is worn, and the second support is arranged on the side that will be integrally molded with the resin material (lens substrate 40) during the processing of the polarized lens, as described below.

[0024] The transmittance of the optical laminate can be measured, for example, using a spectrophotometer. In this case, natural light is used as the light source, and in the visible light region (wavelength region of 400 nm to 700 nm, or 380 nm to 780 nm), the measurement sample is placed so that the transmission axis or absorption axis is oriented at 0 degrees and 90 degrees, and the respective transmittances are measured under detection conditions of a predetermined pitch. The average value of these transmittances is obtained as the transmittance of the optical laminate. From the obtained transmittance, the luminosity-corrected single transmittance Ys (unit: %, the term "single" refers to the case of one polarizing element), the luminosity-corrected polarization degree Py (unit: %), and the hue (JIS Z 8781-4:2013 CIE 1976 L ＊ a ＊ b ＊ It is possible to calculate the color space.

[0025] (Support) The support is an optically transparent resin material used to protect the polarizing element and to impart rigidity and integral molding to the polarized lens. In addition to the first support and the second support, a third support may also be provided depending on the design of the optical laminate. The first support, the second support, and even the third support may be made of the same material, or may be made of different materials depending on the design of the optical laminate. Furthermore, each member of the optical laminate can be laminated via an adhesive layer. The film thickness of each support is usually 10 μm or more and 200 μm or less, preferably 40 μm or more and 100 μm or less, and a film or sheet-form material can be used.

[0026] The material of the support may be, for example, a material containing a polycarbonate (PC)-based resin, a triacetyl cellulose (TAC)-based resin, a polyamide (PA)-based resin, or the like, and may be appropriately changed depending on the type of injection molding resin. In this case, to ensure adhesion, it is desirable that the injection molding resin of the lens substrate and the support of the optical laminate are made of the same material, but this is not limited thereto. In addition, the first support, the second support, and even the third support may be the same support, or may be different types of support.

[0027] At least one support or at least one adhesive layer in the optical laminate may contain an ultraviolet absorber. In this case, such an adhesive layer is preferably an adhesive layer disposed on the first support or between the first support and the polarizing element, which not only protects the wearer's eyes from ultraviolet light but also suppresses photodegradation of the support, polarizing element, and specific wavelength-absorbing dye. However, the arrangement of the component having ultraviolet absorbing function is not limited to the above method and may be disposed at any position in the optical laminate or lens substrate.

[0028] (Polarizing Element) The polarizing element used in the present invention is a polyvinyl alcohol (PVA) polarizing film. PVA polarizing films can be produced by known stretching methods, in which a dye such as iodine or a dichroic dye is adsorbed onto a polymer film containing PVA or a derivative thereof, and the film is then uniaxially stretched and oriented by approximately 2 to 5 times its original size. In this case, the thickness of the polarizing element is typically 10 μm or more and 35 μm or less. In particular, from the standpoint of hue design and designability, a dichroic dye is preferred as the dye, and furthermore, from the standpoint of heat resistance, a direct dye containing an azo dye having a sulfonic acid group is preferred. A polarizing element made of a PVA polarizing film is also referred to as a polarizing film.

[0029] The dichroic dye can be used alone or in combination of two or more depending on the hue design of the polarizing element. Examples of such dichroic dyes include C.I. Direct Yellow 12, C.I. Direct Yellow 28, C.I. Direct Yellow 44, C.I. Direct Yellow 142, C.I. Direct Orange 26, C.I. Direct Orange 39, C.I. Direct Orange 71, C.I. Direct Orange 107, C.I. Direct Red 2, C.I. Direct Red 31, C.I. Direct Red 79, C. I. Direct Red 81, C. I. Direct Red 117, C. I. Direct Red 247, C. I. Direct Green 80, C. I. Direct Green 59, C. I. Direct Blue 71, C. I. Direct Blue 78, C. I. Direct Blue 168, C. I. Direct Blue 202, C. I. Direct Violet 9, C. I. Direct Violet 51, C. I. Examples of suitable acrylic acid esters include C.I. Direct Brown 106 and C.I. Direct Brown 223.

[0030] Other dichroic dyes may be used that are produced by known methods. Examples of known methods include the method described in JP-A-3-12606 and the method described in JP-A-59-145255. Examples of commercially available dyes include Kayafect Violet P Liquid (manufactured by Nippon Kayaku Co., Ltd.), Kayafect Yellow Y, Kayafect Orange G, Kayafect Blue KW, and Kayafect Blue Liquid 400.

[0031] The polarizing element used in the present invention is preferably a "gray color" and has a hue that can be expressed as exhibiting a neutral gray hue (also called an achromatic hue) from the viewpoint of easily designing a variety of color tones in combination with a hue-adjusting dye described later.＊ a ＊ b ＊ As the hue value in the color space, L ＊ s is 70 or less, and a ＊ s and b ＊ s are each in the range of -5 or more and 5 or less. Furthermore, it is more preferable that the optical characteristics of the polarizing element simultaneously satisfy a luminosity-corrected single transmittance (Ys) of 50% or less and a luminosity-corrected polarization degree (Py) of 99.0% or more, thereby imparting high polarization characteristics to the optical laminate. For example, an example of a polarizing element for polarized sunglasses containing a commercially available dichroic dye that exhibits such optical characteristics is NYSH-30 (Ys = 38.1%, Py = 99.6%, L) manufactured by Nippon Kayaku Co., Ltd., which is made of a PVA-based resin film. ＊ s = 68.1, a ＊ s = -0.8, b ＊ s=5.0), which is suitable for application as the polarizing element of the present invention.

[0032] In the definition of polarized sunglasses, they are generally classified as polarized sunglasses with a polarization degree of 90% or more, and sunglasses with a polarization function with a polarization degree of less than 90%, and the product names are also different. Furthermore, polarizing elements with a polarization degree of 90% or more have high anti-glare properties, so the use of polarizing elements with such a high polarization degree is particularly preferred.

[0033] In particular, polarizing elements such as the above-mentioned NYSH-30 have excellent optical properties as polarizing elements used before hue adjustment, and not only are they easy to redesign for various hues and transmittance, but they also have sufficient polarization properties in the wavelength range of 700 nm or more. Therefore, by using such polarizing elements, it is possible to design polarized sunglasses with a wider visible light range and higher light-blocking effect than conventional dye-based polarized sunglasses.

[0034] In addition to the above-mentioned polarizing elements, depending on the optical design of the optical laminate, for example, polarizing elements with different transmittances or hues, reflective polarizing elements, polarizing elements having a light-emitting function containing the dye disclosed in Republished Patent Publication No. 2019 / 022211, etc. may be used in combination, and the polarizing elements used in the present invention can be arranged at any position in the optical laminate together with these.

[0035] (Adhesive Layer) The adhesive layer is a layer for adhering the support and the polarizing element. A resin material containing at least a base polymer (hereinafter also referred to as the main agent) and a curing aid such as a crosslinking agent can be used as the adhesive layer. Depending on the dilution component of the adhesive, the adhesive may be water-based, solvent-based, or solventless, and the type may be appropriately selected according to the surface properties of the adherend and the curing method. In consideration of compatibility with the hue-adjusting dye described below, the adhesive layer included in the optical laminate of the present invention is preferably a solvent-based or solventless adhesive layer. A solvent-based adhesive layer is particularly preferred because of the ease of preparing the dye solution and adjusting the dye concentration and transmittance in the system. Hereinafter, a solvent-based or solventless adhesive layer will be referred to as a "solvent-based or solventless adhesive layer," and a water-based adhesive layer will be referred to as an "aqueous adhesive layer."

[0036] The adhesive layer is provided to bring the support and the polarizing element or the support and another support into close contact, and at least one layer may be included in the optical laminate, or multiple layers may be provided depending on the design of the optical laminate. Furthermore, when a TAC-based resin film is used as the support of the optical laminate, the polarizing element or the TAC-based resin films may be laminated together with an aqueous adhesive layer, and the aqueous adhesive layer may be used in combination with a solvent-based or solventless adhesive layer.

[0037] In solvent-based or solventless adhesive layers, transparent photocurable resins or thermosetting resins can be preferably used as the main component, examples of which include acrylic resins, urethane resins, epoxy resins, silicone resins, rubber resins, polyvinyl ether resins, and polyester resins. In particular, when processing a polarized lens using an optical laminate and a lens substrate, as described below, steps of shaping with heat and integral molding with a resin are required, and therefore, from the viewpoint of these moldability, it is preferable that the adhesive layer contain a thermosetting resin, and among these, it is particularly preferable that it contain an amorphous polyester resin.

[0038] The amorphous polyester resin is preferably soluble in organic solvents, has a mass average molecular weight of 15,000 or more and 30,000 or less, and has a glass transition temperature of -20°C or more and 20°C or less. These properties enable the formation of an adhesive layer that is excellent in lens processability and interlayer adhesion, and further allows for easy layer formation by the coating method described below. Examples of commercially available amorphous polyester resins include the "Vylon" series (product numbers: 200, 240, 245, 500, etc.) manufactured by Toyobo MC Co., Ltd.

[0039] A curing agent may be added to the amorphous polyester resin together with the dilution solvent. The type of curing agent is not particularly limited, but isocyanate compounds are preferred. Furthermore, a curing aid (also called a curing catalyst) or the like may be further added to accelerate curing and control physical properties. The dilution solvent is not particularly limited as long as it dissolves the resin and various additives, but examples thereof include methyl ethyl ketone (MEK), cyclopentanone (CPN), and cyclohexanone (CHN).

[0040] (Hue-Adjusting Dye) At least one adhesive layer used in the present invention contains one or more hue-adjusting dyes that adjust the hue and visible light transmittance of the optical laminate. The hue-adjusting dye has a maximum absorption wavelength (also referred to as λmax) in the visible light range and is used to adjust the hue and visible light transmittance of the optical laminate. The hue-adjusting dye may be contained in at least one adhesive layer, and one or more types may be blended into the adhesive layer depending on the optical design. Furthermore, it is preferable that the hue-adjusting dye does not interact with the specific wavelength-absorbing dye (described below), such as by decomposition or aggregation, and is compatible with or dispersible in the resin component of the adhesive layer. Materials commonly referred to as "resin coloring dyes" can be used as the hue-adjusting dye. In an optical laminate containing a hue-adjusting dye, the transmittance of a specific wavelength range or the entire visible light range is reduced relative to the polarizing element.

[0041] When a plurality of adhesive layers contain a hue-adjusting dye, various hue-adjusting dyes may be contained separately in each adhesive layer so that the optical laminate has desired optical properties, or the amount of the hue-adjusting dye may be adjusted so that the adhesive layer contains the hue-adjusting dye. The same applies when a specific wavelength absorbing dye described below is used in combination.

[0042] Examples of dyes for resin coloring include Solvent Yellow 33, Disperse Yellow 54, Disperse Yellow 160, Disperse Yellow 201, Solvent Orange 60, Solvent Red 111, Solvent Red 135, Solvent Red 168, Solvent Red 207, Disperse Red 22, Solvent Red 52, Solvent Red 179, Disperse Red 60, Disperse Violet 31, Solvent Blue 36, and Solvent Violet Solvent Blue 13, Disperse Blue 14, Solvent Blue 94, Solvent Blue 63, Solvent Blue 104, Solvent Blue 97, Solvent Green 20, Solvent Violet 13, Disperse Violet 28, Solvent Violet 36, and the like.

[0043] The hue-adjusting dye preferably has heat resistance. The required heat resistance means that the hue-adjusting dye does not decompose or discolor due to heat caused by the thermal history during bending of the optical laminate or lens molding, which will be described later.

[0044] The optical properties of the optical laminate are adjusted using a hue-adjusting dye by incorporating into the adhesive layer at least one, preferably a plurality of, dyes corresponding to each wavelength range in the visible light range selected from (A) to (C) below, based on the transmittance waveform exhibited by the polarizing element. This reduces the transmittance in the wavelength range corresponding to the λmax of each dye, thereby enabling the transmittance waveform to be adjusted across the visible light range and enabling any color tone to be designed. Furthermore, the hue-adjusting dye may be a dye exhibiting another color of the same kind or a dye having multiple light absorption wavelength ranges, as long as it satisfies the objectives of the present invention. (A) Red-based dye (having a maximum absorption wavelength λmax in the wavelength range of 400 nm to 500 nm) (B) Green-based dye (having a maximum absorption wavelength λmax in the wavelength range of 500 nm to 600 nm) (C) Blue-based dye (having a maximum absorption wavelength λmax in the wavelength range of 600 nm to 700 nm)

[0045] (A) Examples of red dyes (having λmax in the wavelength range of 400 nm or more and 500 nm or less) include Solvent Red 111, Solvent Red 135, Solvent Red 168, Solvent Red 207, Disperse Red 22, Solvent Red 52, Solvent Red 179, and Disperse Red 60. (B) Examples of green dyes (having λmax in the wavelength range of 500 nm or more and 600 nm or less) include Solvent Green 3, Solvent Green 20, and Solvent Green 28. (C) Examples of blue dyes (having λmax in the wavelength range of 600 nm or more and 700 nm or less) include Disperse Blue 63, Solvent Blue 104, and Solvent Blue 97.

[0046] As the hue-adjusting dye used in the present invention, for example, in the case of the above (A) red-based dye, Solvent Red 168 represented by the following chemical formula (1) can be particularly preferably used; in the case of the above (B) green-based dye, Solvent Green 20 represented by the following chemical formula (2); and in the case of the above (C) blue-based dye, Solvent Blue 97 represented by the following chemical formula (3) can be particularly preferably used.

[0047]

[0048]

[0049]

[0050] As commercially available hue-adjusting dyes, for example, Plast Red 8320 of the Plast series manufactured by Arimoto Chemical Industry Co., Ltd. can be used for Solvent Red 168, Plast Green 8645 manufactured by the same company can be used for Solvent Green 20, and Plast Blue 8590 manufactured by the same company can be used for Solvent Blue 97.

[0051] Furthermore, the hue-adjusting dye used in the present invention adjusts the transmittance in the wavelength range of 380 nm or more and 500 nm or less, and therefore (D) a yellow-based dye may be used as a dye having λmax in this wavelength range. By using this dye in combination with the above-mentioned (A) red-based dye, (B) green-based dye, and (C) blue-based dye, waveform adjustment can be more optimally performed.

[0052] (D) Examples of yellow dyes (having a maximum absorption wavelength λmax in the wavelength range of 380 nm or more and 500 nm or less) include Solvent Yellow 33, Disperse Yellow 54, Disperse Yellow 160, Disperse Yellow 201, and Disperse Yellow 60. Among these, it is particularly preferable to use Disperse Yellow 201, which has a phenylcarbamic acid structure represented by the following chemical formula (4). An example of commercially available Disperse Yellow 201 is Yellow 8070 from Arimoto Chemical Industry Co., Ltd.'s Plast Yellow series, and the λmax of this dye in the resin is a wavelength of 446 nm.

[0053]

[0054] The amount of each of the dyes (A) to (D) alone is, for example, 0.001 to 0.5 parts by weight, preferably 0.002 to 0.4 parts by weight, per 100 parts by weight of the base material of the adhesive layer. Furthermore, when all of the dyes (A) to (D) are used in combination, the total amount is 0.004 to 2.0 parts by weight, preferably 0.008 to 1.6 parts by weight, per 100 parts by weight of the base material. By including the dyes (A) to (D) in such amounts, when the polarizing element and the adhesive layer are laminated, the transmittance is reduced by 10% to 15% compared to the gray polarizing element before lamination, thereby allowing the optical laminate to exhibit the desired hue. Furthermore, by having the total amount of the dyes (A) to (D) within the above range, leaching of the dyes can be suppressed during lens processing of the optical laminate and during use of the lens.

[0055] (Specific Wavelength Absorbing Dye) At least one adhesive layer used in the present invention may further contain a specific wavelength absorbing dye in addition to the above-mentioned hue-adjusting dye. The specific wavelength absorbing dye is used, particularly in eyewear, to absorb light within a specific wavelength range in the visible light region from incident light (external light) in order to increase the contrast of the field of view and impart effects such as anti-glare properties.

[0056] The specific wavelength absorbing dye preferably has heat resistance. The required heat resistance means that the specific wavelength absorbing dye is not decomposed or discolored by heat due to the thermal history caused by bending of the optical laminate or lens molding, which will be described later.

[0057] The specific wavelength absorbing dye may be blended in one or more types in the adhesive layer depending on the optical design. The specific wavelength absorbing dye preferably has optical characteristics of λmax in the wavelength range of 570 nm to 600 nm, with a half-width of approximately 10 nm to 60 nm. Examples of such specific wavelength absorbing dyes include cyanine-based, squarylium-based, xanthene-based, oxonol-based, azo-based, and tetraazaporphyrin-based dyes, and particularly preferred are tetraazaporphyrin-based dyes that exhibit a blue to purple color and are represented by the following chemical formula (5):

[0058] (In formula (5), R １ ~R ８ each independently represents a hydrogen atom, a halogen atom, a nitro group, a cyano group, a hydroxy group, an amino group, a carboxy group, a sulfonic acid group, a linear, branched, or cyclic alkyl group having 1 to 20 carbon atoms, an alkoxy group having 1 to 20 carbon atoms, an aryloxy group having 6 to 20 carbon atoms, a monoalkylamino group having 1 to 20 carbon atoms, a dialkylamino group having 2 to 20 carbon atoms, a dialkylamino group having 7 to 20 carbon atoms, an aralkyl group having 7 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, a heteroaryl group, an alkylthio group having 6 to 20 carbon atoms, or an arylthio group having 6 to 20 carbon atoms, and may form a ring other than an aromatic ring via a linking group; M represents two hydrogen atoms, a divalent metal atom, a divalent mono-substituted metal atom, a tetravalent di-substituted metal atom, or an oxymetal atom.

[0059] In particular, the tetraazaporphyrin dye is represented by the formula (5), where M is divalent Cu and R １ ~R ８ are R １ and R ２ , R ３ and R ４ , R ５ and R ６ and R ７ and R ８A tert-butyl group (t-C ４ H ９ It is preferred that the substituted aryl group is a positional isomer.

[0060] (Adjusting the hue of the optical laminate) Adjusting the hue of the optical laminate of the present invention includes using a polarizing element having a gray color, which is a general-purpose color tone, as a reference and simply adjusting the transmittance of the polarizing element from its gray color to a transmittance suitable for sunglasses without changing its hue much, and adjusting the transmittance of the polarizing element from its gray color to a desired hue while changing it to a transmittance suitable for sunglasses.

[0061] The polarizing element used in the optical laminate of the present invention preferably has a transmittance higher than the transmittance finally exhibited by the optical laminate and also has higher polarization properties. The luminosity-corrected single transmittance (Ys) is preferably 25% or more and 45% or less, and more preferably 35% or more and 43% or less. The luminosity-corrected polarization degree (Py) is preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more. By combining a polarizing element having such optical properties with an adhesive layer containing the above-mentioned hue-adjusting dye, it is possible to easily design a variety of color tones from a single type of polarizing element without producing polarizing elements color-adjusted for each type, and an optical laminate exhibiting high polarization properties can be obtained.

[0062] Table 1 shows an example of the design of the optical properties of an optical laminate obtained by comprising a gray polarizing element, which is a general-purpose color tone, preferably a gray dye-based polarizing element having optical properties of a luminous efficacy-corrected single transmittance (Ys) of 25% or more and 40% or less, and a luminous efficacy-corrected polarization degree (Py) of 90% or more, and an adhesive layer containing a hue-adjusting dye; however, the optical laminate of the present invention is not limited to this.

[0063]

[0064] With regard to the color tone names exemplified in Table 1, because the optical laminate of the present invention is adjusted to the same or equivalent hue as that of a conventional sunglass product having a bare polarizing film, some of the same names as the conventional ones are used, with the suffix "D" added to distinguish them. Each color tone uses the general name and the median value of Ys, and "D" stands for design.

[0065] In Table 1, the toning name "Grey-15D" has a Ys of 10 to 30% and a hue value of ＊ s = -10.0 to -0.0 and b ＊ It is designed to exhibit a gray color that satisfies s = -5.0 to 5.0. An optical laminate with the toning name "Gray 15" can be obtained, for example, by containing in the optical laminate 0.1% by mass to 0.5% by mass of the dye represented by the above formula (1), 0.1% by mass to 0.5% by mass of the dye represented by the above formula (2), 0.01% by mass to 0.2% by mass of the dye represented by the above formula (3), and 0.001% by mass to 0.5% by mass of the dye represented by the above formula (4).

[0066] In Table 1, the toning name "Grey-30D" has a Ys of 10 to 30% and a hue value of ＊ s = -5.0 to 5.0 and b ＊ It is designed to exhibit a gray color that satisfies s = -5.0 to 5.0. An optical laminate having the toning name "Gray 30" can be obtained, for example, by including in the optical laminate the dye represented by the above formula (1) in a mass ratio of 0.05% by mass to 0.5% by mass, the dye represented by the above formula (2) in a mass ratio of 0.01% by mass to 0.5% by mass, and the dye represented by the above formula (3) in a mass ratio of 0.01% by mass to 0.1% by mass.

[0067] In Table 1, the color name "Marron-20D" has a Ys of 10 to 30% and a hue value of ＊ s = -5.0 to 5.0 and b ＊It is designed to exhibit a maroon color that satisfies s = 10.0 to 20.0. An optical laminate with the color matching name "Maroon 20" can be obtained, for example, by incorporating in the optical laminate the dye represented by the above formula (1) in a mass ratio of 0.1% to 0.5% by mass, the dye represented by the above formula (2) in a mass ratio of 0.1% to 0.5% by mass, the dye represented by the above formula (3) in a mass ratio of 0.01% to 0.05% by mass, and the dye represented by the above formula (4) in a mass ratio of 0.01% to 0.05% by mass.

[0068] In Table 1, the color name "Brown-30D" has a Ys of 10 to 30% and a hue value of ＊ s = -5.0 to 5.0 and b ＊ It is designed to exhibit a brown color that satisfies s = 15.0 to 25.0. An optical laminate having the color matching name "Brown 30" can be obtained, for example, by containing in the optical laminate 0.05% by mass or more and 0.5% by mass or less of the dye represented by the above formula (1), 0.01% by mass or more and 0.5% by mass or less of the dye represented by the above formula (2), 0.001% by mass or more and 0.05% by mass or less of the dye represented by the above formula (3), and 0.01% by mass or more and 0.05% by mass or less of the dye represented by the above formula (4).

[0069] In Table 1, the color name "Ruby 15D" (Ruby-15D) has a Ys of 10 to 30% and a hue value of a ＊ s = 10.0 to 20.0 and b ＊ It is designed to exhibit a ruby ​​color that satisfies s = 10.0 to 20.0. An optical laminate with the color matching name "Ruby 15" can be obtained, for example, by containing in the optical laminate 0.1% by mass to 0.5% by mass of the dye represented by the above formula (1), 0.1% by mass to 0.5% by mass of the dye represented by the above formula (2), 0.001% by mass to 0.05% by mass of the dye represented by the above formula (3), and 0.001% by mass to 0.05% by mass of the dye represented by the above formula (4).

[0070] In Table 1, the color name "Ruby 30D" (Ruby-30D) has a Ys of 10 to 30% and a hue value of a ＊ s = 5.0 to 15.0 and b ＊It is designed to exhibit a ruby ​​color that satisfies s = 5.0 to 15.0. An optical laminate having the color matching name "Ruby 30" can be obtained, for example, by incorporating in the optical laminate the dye represented by the above formula (1) in a mass ratio of 0.05% by mass to 0.5% by mass, the dye represented by the above formula (2) in a mass ratio of 0.001% by mass to 0.5% by mass, the dye represented by the above formula (3) in a mass ratio of 0.001% by mass to 0.5% by mass, and the dye represented by the above formula (4) in a mass ratio of 0.001% by mass to 0.05% by mass.

[0071] In Table 1, the color name "Leaf-28D" has a Ys of 10 to 30% and a hue value of ＊ s = -15.0 to -5.0 and b ＊ It is designed to exhibit a green color that satisfies s = 15.0 to 25.0. An optical laminate with the toning name "Leaf 28" can be obtained, for example, by containing in the optical laminate 0.05% by mass or more and 0.5% by mass or less of the dye represented by the above formula (1), 0.01% by mass or more and 0.5% by mass or less of the dye represented by the above formula (2), 0.001% by mass or more and 0.05% by mass or less of the dye represented by the above formula (3), and 0.01% by mass or more and 0.05% by mass or less of the dye represented by the above formula (4).

[0072] (Method of Forming Adhesive Layer) The adhesive layer can be formed by a known coating method such as flow coating, spraying, bar coating, gravure coating, roll coating, blade coating, air knife coating, lip coating, comma coater method, die coater method, etc. In the present invention, in view of the physical properties of the components that form the adhesive layer, which will be described later, the comma coater method and die coater method can be particularly preferably used.

[0073] The adhesive layer containing the hue-adjusting dye is formed by applying an adhesive composition containing the above-mentioned main agent and the hue-adjusting dye to a base substrate so that the thickness after solvent removal is typically 5 μm to 50 μm, preferably 15 μm to 30 μm. If the thickness is less than 5 μm, sufficient interlayer adhesion strength may not be obtained. Furthermore, if the thickness exceeds 50 μm, fluctuations or undulations may occur on the coated surface, which may affect visibility when the resulting optical laminate is applied to eyewear. The base substrate refers to a substrate onto which the adhesive composition is directly applied to form an adhesive layer. In the present invention, the adhesive composition may be applied directly to a support, or may be applied to a polyethylene terephthalate (PET) resin film (also referred to as a release film) coated with a release agent, and then the adhesive layer may be transferred to the polarizing element surface or the support surface by transfer. The thickness of the aqueous adhesive layer not containing a hue-adjusting dye is usually 0.01 μm or more and 1 μm or less, and can be estimated, for example, by observing the cross section of the produced optical laminate with a scanning electron microscope (SEM). The lower limit of the thickness of the aqueous adhesive layer is, for example, 0.01 μm or more.

[0074] The adhesive composition applied to the base substrate is typically dried at a temperature of 40 to 140°C, preferably 80 to 130°C, for 1 to 3 minutes to remove the solvent, thereby obtaining the adhesive layer of the present invention. In addition, in the drying method using the above temperature conditions, it is desirable to provide multiple drying ovens and gradually increase the temperature from low to high in order to form an adhesive layer with a good surface appearance. Furthermore, the air surface is laminated with the surface of the support or polarizing element that will be the adherend surface of the optical laminate described below. At this time, one or both surfaces of the support or polarizing element that will be the adherend surface may be subjected to a surface modification treatment such as corona treatment or plasma treatment to improve adhesion.

[0075] After the above-described lamination, an aging treatment may be carried out to promote the crosslinking reaction of the curing agent in the adhesive layer. The conditions for the aging treatment vary depending on the type of resin and crosslinking agent used, but the adhesive layer used in the present invention is preferably kept in a thermostatic chamber at 25 to 50°C, preferably 35 to 40°C, for about one day to one week. From the viewpoint of improving the adhesion between the layers, the aging treatment is preferably carried out after laminating one surface of the support, which will be the adherend surface, and the surface of the polarizing element via the adhesive layer.

[0076] <Method for manufacturing optical laminate> The method for manufacturing the optical laminate of the present invention includes step a) of forming a polarizing element, step b) of forming an adhesive layer, and step c) of laminating the support and the polarizing element using the adhesive layer, and for example, the steps may be performed continuously in order starting from the step of forming the polarizing element, or each step may be performed sequentially.

[0077] From the viewpoint of ease of manufacturing and quality stability, step b) of forming the adhesive layer preferably includes a step of dissolving various dyes in a solvent and then mixing the resulting solution with the main component of the adhesive layer. Specifically, the various dyes are dissolved in the same solvent as the dilution solvent used for the main component, and the resulting dye solution is blended into the main component or a solution of the main component. This allows the various dyes to be uniformly mixed in the main component. The term "dissolved" also includes the meaning of a uniformly dispersed state.

[0078] Furthermore, when preparing various dyes, each dye solution may be prepared using the same dilution solvent, and each dye solution may be mixed simultaneously or sequentially into the main agent or the main agent solution, or a dye solution in which all dyes are mixed together using the same dilution solvent may be prepared, and then mixed into the main agent or the main agent solution.

[0079] Hereinafter, examples of producing the optical laminate according to the present invention will be described, but the types and blending amounts of the various materials are not limited to those described below.

[0080] In step a) of forming a polarizing element, a gray PVA-based polarizing film that uses a dichroic dye to exhibit predetermined optical properties is used as the polarizing element, and a TAC-based resin film is used as the first support. Based on a known method for producing a polarizing plate, a polarizing element is produced that has a support (first support) on only one side via an aqueous adhesive layer made of a PVA-based resin material.

[0081] In step b) of forming the adhesive layer, a base solution containing an amorphous polyester resin as a base, cyclohexanone as a diluting solvent, isocyanate as a curing agent, and dibutyltin dilaurate (DBSn) as a curing catalyst is prepared. At this time, the various materials are mixed in a ratio of 20 to 40 parts by mass of cyclohexanone, preferably 25 to 35 parts by mass, 1 to 3 parts by mass of a polyisocyanate compound solution (manufactured by Soken Chemical & Engineering Co., Ltd., "590E"), and 0.005 to 0.020 parts by mass, preferably 0.008 to 0.015 parts by mass of DBSn, based on 100 parts by mass of the amorphous polyester resin.

[0082] Next, a dye solution containing Disperse Yellow 201, Solvent Blue 97, Solvent Red 168, and Solvent Green 20 as hue-adjusting dyes is prepared. At this time, based on 100 parts by mass of the amorphous polyester resin contained in the adhesive composition, cyclohexanone as a diluent solvent is mixed in an amount of 1 part by mass to 25 parts by mass, preferably 5 parts by mass to 18 parts by mass, Disperse Yellow 201 is mixed in an amount of 0.001 parts by mass to 0.03 parts by mass, preferably 0.008 parts by mass to 0.025 parts by mass, and Solvent Blue 97, Solvent Red 168, and Solvent Green 20 are mixed in the dye solution in an amount of 0.001 parts by mass to 0.8 parts by mass, preferably 0.01 parts by mass to 0.5 parts by mass. By uniformly mixing the base solution and the dye solution, an adhesive composition containing the base solution and various dyes can be prepared.

[0083] In step c) of laminating the support and the polarizing element using the adhesive layer, the obtained adhesive composition is applied to a PA-based resin film serving as a second support. Next, in the drying step, the solvent is evaporated from the coating film on the PA-based resin film coated with the adhesive composition using multiple drying ovens, each set at a temperature range of 40°C to 100°C. The amount of coating is adjusted so that the thickness of the adhesive layer after drying is 20 μm to 30 μm. The adhesive layer side is then bonded to the polarizing element surface, producing an optical laminate having a laminate structure of first support / water-based adhesive layer / polarizing element / adhesive layer / second support.

[0084] Further, other examples of producing the optical laminate of the present invention will be described, but the types and blending amounts of the various materials are not limited to those described below.

[0085] In step a) of forming a polarizing element, a gray PVA-based polarizing film that uses a dichroic dye to exhibit predetermined optical properties is used as the polarizing element, a TAC-based resin film is used as the first support, and the same TAC-based resin film is used as the second support, and a polarizing element is produced in which both sides are sandwiched between supports (the first support and the second support) via an aqueous adhesive layer made of a PVA-based resin material, based on a known method for manufacturing a polarizing plate.

[0086] In step b) of forming the adhesive layer, a base solution containing an amorphous polyester resin as a base, cyclohexanone as a diluting solvent, isocyanate as a curing agent, and dibutyltin dilaurate (DBSn) as a curing catalyst is prepared. At this time, the various materials are mixed in a ratio of 20 to 40 parts by mass of cyclohexanone, preferably 25 to 35 parts by mass, 1 to 3 parts by mass of a polyisocyanate compound solution (manufactured by Soken Chemical & Engineering Co., Ltd., "590E"), and 0.005 to 0.020 parts by mass, preferably 0.008 to 0.015 parts by mass of DBSn, based on 100 parts by mass of the amorphous polyester resin.

[0087] Next, a dye solution is prepared in the same manner as above, and this dye solution is uniformly mixed with the base solution to prepare an adhesive composition containing the base and various dyes.

[0088] In step c) of laminating the support and the polarizing element using the adhesive layer, the obtained adhesive composition is applied to a release film. Next, in the drying step, the solvent is evaporated from the coating film of the release film coated with the adhesive composition using multiple drying ovens, each set at a temperature range of 40°C to 100°C. The coating amount is adjusted so that the thickness of the adhesive layer after drying is 23 μm to 30 μm. The adhesive layer is then bonded to the second support surface, and the release film is removed. A PA-based resin film is then bonded to the exposed surface of the adhesive layer as a third support, thereby obtaining an optical laminate having a laminate structure of first support / aqueous adhesive layer / polarizing element / aqueous adhesive layer / second support / adhesive layer / third support.

[0089] <Polarized Lens> The polarized lens of the present invention comprises a lens substrate and the above-described optical laminate, and is suitable for use in eyewear. A polarized lens for eyewear can be obtained by molding the optical laminate into a desired shape so that the first support is on the outside (the side opposite the lens substrate). Furthermore, eyewear such as sunglasses or goggles can be obtained by fixing the polarized lens for eyewear to a frame. An example of the process for forming a polarized lens is described below, but the process is not limited to this.

[0090] Polarized lenses can typically be formed by sequentially performing the steps of forming a sheet- (or film-) shaped optical laminate containing polarizing elements, shaping (bending) the optical laminate, insert-molding the shaped optical laminate and a resin, and applying a hard coat to the resulting insert-molded product.

[0091] In order to facilitate processing the optical laminate into a lens shape by combining it with a lens substrate (described later), the optical laminate is subjected to a shaping (bending) process in advance using a heat press or the like. A mold designed to a predetermined size is generally used for the shaping process, and the shape of the mold is appropriately designed according to the design of the eyewear product, etc. FIG. 3 is a schematic diagram showing an example of the shaping (bending) process of the optical laminate according to the present invention. As shown in FIG. 3 , the optical laminate 100 is placed in a bending mold 50 (concave mold), and then the optical laminate 100 is pressed with a hemispherical mold 51 (convex mold, also referred to as a hot iron ball) heated to a predetermined temperature, thereby obtaining a bent optical laminate 101. That is, the second support 12, which is the support on the viewing side of the optical laminate 100, is injection molded using the spherical mold 51, thereby producing the optical laminate 101 bent up to the first support 11.

[0092] The bending conditions are set in consideration of the bendability and heat resistance (discoloration of the polarizing element, etc.) of the optical laminate, with the temperature being 70 to 120° C., preferably 80 to 100° C., and the time being in the range of 1 to 3 minutes. At this time, only a portion of the optical laminate to be used in the subsequent insert molding step may be simultaneously or sequentially trimmed from the sheet-like optical laminate.

[0093] (Lens substrate) The lens substrate is a resin material used for integrating with the optical laminate of the present invention and processing it into a lens shape. In the bending process described above, a resin (also referred to as a lens substrate) may be further injected. In this case, there is an advantage that the thickness unevenness of the optical laminate of the present invention becomes invisible, and even for lenses without focal refractive power, resin injection is performed to produce products that are particularly excellent in impact resistance, appearance, and eye fatigue. In order to prevent deterioration of appearance due to refractive index differences, it is preferable that the injected resin be the same material as the layer with which the injected resin is in contact. For such integration processing, an insert molding method can generally be used.

[0094] The resin used for the lens substrate is not particularly limited, and examples thereof include thermoplastic resins that can be molded by injection molding, and thermosetting resins that can be molded by distillation polymerization or the like and are commonly used for eyewear lenses, etc. Examples of such resins include (meth)acrylic resins such as methyl methacrylate homopolymers and copolymers of methyl methacrylate and one or more other monomers, diethylene glycol bisallyl carbonate resins such as diethylene glycol bisallyl carbonate homopolymers and copolymers of diethylene glycol bisallyl carbonate and one or more other monomers, acrylonitrile-styrene copolymers, halogen-containing copolymers, polysulfide resins such as homopolymers of monomers having sulfide bonds and copolymers of monomers having sulfide bonds and one or more other monomers, polyurea resins, PA resins, PC resins, polystyrene resins, polyolefin resins, polyvinyl chloride resins, polyester resins, PET resins, polyurethane resins, and sulfur-containing urethane resins such as polythiourethane resins, and epoxy resins. From the viewpoint of adhesion to the optical laminate, it is preferable that the material of the lens substrate is the same as the material of the member that comes into contact with the lens substrate. As a specific example of such a resin combination, the support of the optical laminate on the integrated processing side can be made of a PA-based resin, and the lens substrate can also be made of a PA-based resin, thereby fusing the support and the lens substrate.

[0095] <Eyewear> The eyewear of the present invention comprises the above-described polarized lens. The polarized lens may have a hard coating, an anti-reflection film, or the like formed on its surface as appropriate, and the eyewear of the present invention can be produced by fixing the polarized lens to a frame by edging, drilling, screwing, or the like.

[0096] In addition to the ultraviolet absorbing ability achieved by the inclusion of the ultraviolet absorber described above, the eyewear of the present invention may also contain a dye, metal oxide, or the like in any layer of the optical laminate or lens substrate to add infrared absorbing functionality, or may have such a dye or metal oxide laminated between layers, or may have a photochromic material for photochromic functionality, or may have such a material laminated between layers.

[0097] Based on the above embodiments, the present invention relates to the following [1] to [7]: [1] An optical laminate comprising a support, a polarizing element, and at least one adhesive layer between the support and the polarizing element, wherein the polarizing element is a polarizing element conforming to CIE 1976 L ＊ a ＊ b ＊ Hue value a in color space ＊ s and b ＊ An optical laminate comprising a gray polyvinyl alcohol-based polarizing film in which each of s is in the range of -5 to 5, and at least one of the adhesive layers contains a plurality of hue-adjusting dyes that adjust the hue and transmittance in the visible light region of the optical laminate, the hue-adjusting dyes including at least one of the following dyes (A) to (C): (A) a blue dye (having a maximum absorption wavelength in the wavelength region of 600 to 700 nm), (B) a green dye (having a maximum absorption wavelength in the wavelength region of 500 to 600 nm), or (C) a red dye (having a maximum absorption wavelength in the wavelength region of 400 to 500 nm). [2] The optical laminate according to [1] above, wherein the adhesive layer contains an amorphous polyester-based resin. [3] The optical laminate according to [1] or [2] above, wherein the polarizing element is a dye-based polarizing element having optical properties of a luminous efficiency-corrected single transmittance of 25% to 45% and a luminous efficiency-corrected polarization degree of 90% or more. [4] A polarized lens comprising a lens substrate and the optical laminate described in [1] or [2] above, wherein a support on the viewing side of the optical laminate is injection molded. [5] A polarized lens comprising a lens substrate and the optical laminate described in [3] above, wherein a support on the viewing side of the optical laminate is injection molded. [6] Eyewear comprising the polarized lens described in [4] above. [7] Eyewear comprising the polarized lens described in [5] above.

[0098] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to these examples.

[0099] [Example 1] (1) Preparation of Polarizing Element The polarizing element used was "NYSH-30" manufactured by Nippon Kayaku Co., Ltd., a dye-based PVA resin film for polarized sunglasses. The optical properties of this polarizing element were measured using a spectrophotometer "U-4100" manufactured by Hitachi High-Tech Science Corporation, and the luminous efficiency-corrected single transmittance (Ys) was 38.1%, and the luminous efficiency-corrected polarization degree (Py) was 99.9%. ＊ a ＊ b ＊ The hues in the color space are L ＊ s = 68.1, a ＊ s = -0.8, and b ＊ s=5.0.

[0100] (2) Preparation of adhesive composition An adhesive composition was obtained containing an organic solvent-soluble polyester resin (manufactured by Toyobo Co., Ltd., "Vylon 500", resin solids content 44.9%) as the main component of the adhesive composition, 2 mass% of an isocyanate-based curing agent (manufactured by Soken Chemical & Engineering Co., Ltd., "590E"), 0.01 mass% of dibutyltin dilaurate (DBSn), 0.012 mass% of a yellow-based dye Disperse Yellow 201, 0.094 mass% of a blue-based dye Solvent Blue 97, 0.257 mass% of a green-based dye Solvent Green 20, and 0.243 mass% of a red-based dye Solvent Red 168 as hue-adjusting dyes, in a ratio of 11 mass% of cyclohexanone as a diluting solvent. Here, each dye was dissolved in a diluent solvent in advance, and then this dye solution was uniformly mixed with a base solution containing the base resin, curing agent, DBSn, and diluent solvent. The viscosity of the resulting adhesive composition was measured using a viscometer "TVB-10M" manufactured by Toki Sangyo Co., Ltd., and was in the range of 300 mPa s to 600 mPa s.

[0101] (3) Preparation of Optical Laminate The obtained polarizing element and a TAC film (manufactured by Fujifilm Corporation, "TD-80UL", film thickness 80 μm) that had been saponified (immersed in a 2N sodium hydroxide aqueous solution at 40°C for 10 minutes) as a first support were bonded together using an aqueous adhesive layer containing a PVA resin (solid content of the PVA resin was 2.0 mass%, thickness 0.1 μm), and the layer was dried at 80°C for 3 minutes to remove moisture, thereby adhering the polarizing element and the first support, thereby preparing a polarizing element having a first support on one side of the polarizing element.

[0102] Next, the obtained adhesive composition was applied by a die coater method to one side of a PA resin film (manufactured by LOFO, "TRF-800", film thickness 80 μm) as a second support, and this coating film was dried at 100°C for 3 minutes to remove the solvent, thereby producing an adhesive layer (thickness 24 μm). Thereafter, the surface of the produced polarizing element and the air side of the adhesive layer (the surface on which the second support was not placed) were bonded together to obtain an optical laminate having a laminate structure of first support / aqueous adhesive layer / polarizing element / adhesive layer / second support, with the color name "Grey-15D".

[0103] Furthermore, the obtained optical laminate was kept at 35°C for one week as an aging treatment to promote the curing reaction of the adhesive layer and to enhance the adhesion between the polarizing element and the second support. The optical properties of the obtained optical laminate were measured using a spectrophotometer "U-4100" manufactured by Hitachi High-Tech Science Corporation, including Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0104] [Example 2] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with a hue-adjusting dye containing 0.024 mass% Disperse Yellow 201, 0.012 mass% Solvent Blue 97, 0.221 mass% Solvent Green 20, and 0.273 mass% Solvent Red 168, and an optical laminate with the color name "Marron-20D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0105] [Example 3] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with a hue-adjusting dye containing 0.020 mass% Disperse Yellow 201, 0.011 mass% Solvent Blue 97, 0.198 mass% Solvent Green 20, and 0.330 mass% Solvent Red 168, and an optical laminate with the color name "Ruby-15D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0106] [Example 4] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with a hue-adjusting dye containing 0.024 mass% Disperse Yellow 201, 0.007 mass% Solvent Blue 97, 0.162 mass% Solvent Green 20, and 0.123 mass% Solvent Red 168, and an optical laminate with the color-matching name "Leaf-28D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0107] [Example 5] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with hue-adjusting dyes of 0.032 mass% Solvent Blue 97, 0.071 mass% Solvent Green 20, and 0.083 mass% Solvent Red 168, and an optical laminate with the color-matching name "Grey-30D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0108] [Example 6] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with a hue-adjusting dye containing 0.024 mass% Disperse Yellow 201, 0.004 mass% Solvent Blue 97, 0.071 mass% Solvent Green 20, and 0.123 mass% Solvent Red 168, and an optical laminate with the color name "Brown-30D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0109] [Example 7] An optical laminate was produced in the same manner as in Example 1, except that the adhesive composition produced in Example 1 was replaced with a hue-adjusting dye containing 0.008 mass% Disperse Yellow 201, 0.002 mass% Solvent Blue 97, 0.036 mass% Solvent Green 20, and 0.118 mass% Solvent Red 168, and an optical laminate with the color name "Ruby-30D" was obtained. The optical properties of the obtained optical laminate were measured for Ys, Py, and L. ＊ a ＊ b ＊ The hue was measured in color space, and the results are shown in Table 2.

[0110] [Comparative Example 1] (1) Preparation of Polarizing Element The polarizing element used was "Grey-15" manufactured by Nippon Kayaku Co., Ltd., a dye-based PVA-based resin film for polarized sunglasses. The optical properties of this polarizing element were measured using a spectrophotometer "U-4100" manufactured by Hitachi High-Tech Science Corporation, and the luminous efficiency-corrected single transmittance (Ys) was 15.1% and the luminous efficiency-corrected polarization degree (Py) was 99.8%. ＊ a ＊ b ＊ The hues in the color space are L ＊ s = 45.8, a ＊ s = -6.2, and b ＊ s=1.1.

[0111] (2) Preparation of Adhesive Composition An adhesive composition was prepared in the same manner as in Example 1, except that no hue-adjusting dye was added.

[0112] (3) Preparation of Optical Laminate An optical laminate was prepared in the same manner as in Example 1, except that the adhesive composition prepared in (2) of Comparative Example 1 was used. The optical properties of the obtained optical laminate were measured using the Ys and Py values, as well as the L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0113] [Comparative Example 2] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Marron-20" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys was 20.7%, Py was 99.8%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 52.7, a ＊ s = 4.0, and b ＊ The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0114] [Comparative Example 3] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Ruby-15" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys was 16.6%, Py was 99.8%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 47.6, a ＊ s = 15.8, and b ＊The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0115] [Comparative Example 4] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Leaf-28" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys = 28.0%, Py = 99.6%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 59.9, a ＊ s = -9.4, and b ＊ The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0116] [Comparative Example 5] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Grey-30" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys = 30.0%, Py = 99.6%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 61.8, a ＊ s = 0.4, and b ＊ s = 1.4. In addition, the optical properties of the obtained optical laminate were Ys and Py, and further L ＊ a ＊ b ＊The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0117] [Comparative Example 6] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Brown-30" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys was 30.0%, Py was 99.6%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 61.8, a ＊ s = 2.1, and b ＊ The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0118] [Comparative Example 7] An optical laminate was produced in the same manner as in Comparative Example 1, except that instead of the polarizing element used in Comparative Example 1, a dye-type PVA-based resin film for polarized sunglasses, "Ruby-30" manufactured by Nippon Kayaku Co., Ltd., was used to obtain the optical laminate. When the optical properties of this polarizing element were measured, Ys = 30.0%, Py = 99.6%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 61.8, a ＊ s = 8.6, and b ＊ The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0119] [Reference Example 1] An optical laminate was produced in the same manner as in Comparative Example 1, except that the polarizing element used in Comparative Example 1 was replaced with a dye-type PVA-based resin film for polarized sunglasses, "NYSH-30" manufactured by Nippon Kayaku Co., Ltd. The optical properties of this polarizing element were measured, and the results were Ys = 38.1%, Py = 99.9%, and L ＊ a ＊ b ＊ The hue in the color space is L ＊ s = 68.1, a ＊ s = -0.8, and b ＊ The optical properties of the obtained optical laminate were Ys, Py, and L ＊ a ＊ b ＊ The hue was measured in a color space, and the results are shown in Table 2. The optical properties of the obtained optical laminate were not different from those of the polarizing element.

[0120] Table 2 shows the results of comparing the optical properties of the optical laminates of Examples 1 to 7 and Comparative Examples 1 to 7. Here, Comparative Examples 1 to 7 correspond to optical laminates for conventional polarized sunglasses, which are composed of a polarizing element and a support.

[0121]

[0122] The optical laminate of Example 1 reproduces the optical properties of "Grey-15" of Comparative Example 1, but by using a gray polarizing element and an adhesive layer containing various hue-adjusting dyes, it was possible to obtain optical properties equivalent to those of Comparative Example 1, in which the hue and transmittance of the polarizing element were adjusted in the stretching process. In addition, the hue difference was |Δa ＊ s|=0.3, |Δb ＊ Similarly, in Examples 2 to 7, the same optical characteristics as those of Comparative Examples 2 to 7 were obtained, and the hue was |Δa ＊ s|0.1 to 0.7, |Δb ＊It was confirmed that the range of s| was 0.1 to 1.0, and that the appearance and visibility were comparable to those of the other examples. Furthermore, in the adhesive layer of any of the examples, no problems such as aggregation of the hue-adjusting dye due to the inclusion of multiple hues were observed, and it was confirmed that the hue-adjusting dye was compatible with the adhesive layer.

[0123] The optical laminate of the present invention maintains a high degree of polarization and allows for easier adjustment of hue and optical properties without increasing the number of polarizing elements, making it useful for application to polarized lenses and eyewear (sunglasses, goggles, etc.) using the same.

[0124] REFERENCE SIGNS LIST 10 Support 11 First support 12 Second support 20 Polarizing element 30 Adhesive layer 40 Lens substrate 50 Bending mold (concave mold) 51 Hemispherical mold (convex mold) 100, 110 Optical laminate 101 Bent optical laminate

Claims

1. An optical laminate comprising a support, a polarizing element, and at least one adhesive layer between the support and the polarizing element, wherein the polarizing element is a polarizing element conforming to CIE 1976 L ＊ a ＊ b ＊ Hue value a in color space ＊ s and b ＊ An optical laminate comprising a gray polyvinyl alcohol polarizing film in which each of s is in the range of -5 or more and 5 or less, at least one adhesive layer containing a plurality of hue-adjusting dyes that adjust the hue and transmittance in the visible light region of the optical laminate, the hue-adjusting dyes containing at least one of the following dyes (A) to (C): (A) a blue dye (having a maximum absorption wavelength in the wavelength region of 600 nm or more and 700 nm or less), (B) a green dye (having a maximum absorption wavelength in the wavelength region of 500 nm or more and 600 nm or less), and (C) a red dye (having a maximum absorption wavelength in the wavelength region of 400 nm or more and 500 nm or less).

2. The optical laminate according to claim 1, wherein the adhesive layer contains an amorphous polyester resin.

3. An optical laminate according to claim 1 or 2, wherein the polarizing element is a dye-based polarizing element having optical properties of a luminosity-corrected single transmittance of 25% or more and 45% or less, and a luminosity-corrected polarization degree of 90% or more.

4. A polarized lens comprising a lens substrate and the optical laminate according to claim 1 or 2, wherein the support on the viewing side of the optical laminate is injection molded.

5. A polarized lens comprising a lens substrate and the optical laminate according to claim 3, wherein the support on the viewing side of the optical laminate is injection molded.

6. Eyewear comprising the polarized lens according to claim 4.

7. Eyewear comprising the polarized lens according to claim 5.

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