JP2021004929A5 - - Google Patents

Description

The present invention relates to a polarized sunglasses lens in which a transparent resin layer for a lens is laminated on one side or both sides of a wire grid type polarizing element sheet.

Polarizing plates are used in sunglasses, goggles, eyeglasses, etc. because they have excellent antiglare properties. As an absorption-type polarizing element, such a polarizing plate is made of acrylic on one or both sides of a polarizing thin film formed by adsorbing and orienting iodine or a dichroic dye on a polymer film such as polyvinyl alcohol stretched uniaxially. A system sheet or a cellulose-based sheet laminated and integrated as a protective layer has been widely used.

It has been known that plastic polarized lenses used for sunglasses, goggles, etc. are manufactured by the methods shown in the following (i) to (iii) using an absorption type polarizing element.
(I) A polarizing plate in which a triacetyl cellulose (TAC) sheet is adhesively integrated as a protective layer on both sides of a thin film of an absorption-type polarizing element is processed into a lens shape by thermal molding, and then allyl diglycol carbonate (ADC). , Or CR39) is laminated and integrated by casting polymerization with a monomer or the like. The polarized lens obtained by this method is inferior in heat resistance, and when an ADC resin is used, the impact resistance is lowered and there is a risk of damage.
(Ii) Adhesive processing is applied to one side of a polarizing plate in which a TAC sheet is adhesively integrated as a protective layer on both sides of an absorption-type polarizing thin film, and then processed into a sheet shape or a curved surface or other lens shape by thermoforming. , The thermoplastic resin is laminated and integrated on the adhesive processed surface by injection molding (see Patent Document 1). The polarized lens obtained by this method can improve heat resistance and impact resistance depending on the type of thermoplastic resin to be injected, but it is inferior in productivity due to the large number of processes. There was a possibility that the durability would be inferior due to peeling at the interface with the plastic resin surface.

(Iii) A polarizing plate in which a polycarbonate sheet is attached and integrated as a protective layer on both sides of an absorption-type polarizing thin film is processed into a lens shape such as a curved surface by thermoforming, or a polycarbonate resin is laminated and integrated by injection molding. (See Patent Document 2). The polarized lens obtained by this method is excellent in heat resistance and impact resistance, but has problems of generation of colored interference fringes on the side where sunlight is incident and a decrease in the degree of polarization when viewed from the transmission side. In order to prevent this, it was necessary to use a polycarbonate sheet having a specific birefringence (see Patent Document 3).

In addition, since the wire grid polarizing element is a reflective polarizing element, when it is used for polarized sunglasses, it reflects both sides, so that incident light from not only the objective side but also the eyepiece side is reflected, and the wearer's eyes and the wearer's eyes The inconvenience that the periphery of the eye and the background are reflected on the inner surface on the eyepiece side occurs. In Patent Document 4, the reflective wire grid polarizing portion on the objective side attenuates and blocks the infrared region, and the absorption type linear polarization function portion is arranged on the eyepiece side, and the wire grid polarization partial reflection axis direction and the absorption type polarization function are provided. Disclosed is a polarizing lens in which the absorption axes of the portions are substantially aligned and the fine wire plane of the wire grid is bonded to the absorption type linear polarizing plate. In this polarizing lens, a protective layer is required for the absorption type linear polarizing element, and it is necessary to bond the reflection type wire grid polarizing element layer and the absorption type linear polarization element layer with an adhesive layer. The number of configurations increases and the manufacturing process inevitably becomes complicated.

Japanese Unexamined Patent Publication No. 2004-237649 Japanese Unexamined Patent Publication No. 03-039903 Japanese Unexamined Patent Publication No. 08-254669 Japanese Unexamined Patent Publication No. 2014-139964

The present invention solves the above problems and is excellent in impact resistance, heat resistance, and durability, and does not necessarily require a protective layer, an adhesive layer, an adhesive layer, etc., and provides good polarization and required light transmittance. It is an object of the present invention to provide a polarized sunglasses lens that can be maintained and has a reduced reflectance on the back surface side (eyepiece side).

In view of the above-mentioned prior art, the present inventor uses a wire grid type polarizing element sheet having a high degree of polarization as the polarizing element sheet of the polarized sunglasses lens, and metal reflection corresponding to the wire grid portion of the polarizing element sheet. The width and thickness of the body shall be within a specific range, the shape of the metal reflector near the tip in the thickness direction shall be gradually narrowed, and the length of this gradually narrowing portion shall be within a specific range. As a result, it was found that the above problems could be solved, and the present invention was completed. That is, the gist of the present invention is the invention described in the following (1) to (13).

(1) A polarized sunglasses lens in which a transparent resin layer for a lens is laminated on at least one of the back surface side and the front surface side of a wire grid type polarizing element sheet (W).
The polarizing element sheet (W) uses a transparent sheet (A) as a base material, and a metal reflector is formed on a large number of grooves (C) provided on the surface thereof in a one-dimensional lattice pattern in the same direction and at the same period. (B) is embedded
The average width (a) of the metal reflector (B) excluding the portion (D) that gradually becomes thinner toward the tip is 200 nm or less.
The ratio (b / a) of the average thickness (b) of the metal reflector (B) from the front surface side to the tip end in the back surface direction and the average width (a) is in the range of 4 to 25.
In addition, at least one of the cross-sectional shapes parallel to and perpendicular to the one-dimensional lattice arrangement direction near the tip of the metal reflector (B) in the thickness direction becomes linear or smooth curved and gradually narrows toward the tip. The ratio (c / a) of the average length (c) to the average width (a) of the portion (D) that gradually becomes thinner toward the tip is 1.2 or more. Characterized by that,
Polarized sunglasses lens.

(2) The average length (c) and the average width (a) of the portion (D) in the vicinity of the tip portion of the metal reflector (B) in the thickness direction, which gradually becomes thinner toward the tip, in the tip direction. The polarized sunglasses lens according to (1) above, wherein the ratio (c / a) is in the range of 1.2 to 8.
(3) The shape of the portion (D) in the vicinity of the tip portion of the metal reflector (B) in the thickness direction, which gradually becomes thinner toward the tip, has a cross-sectional shape perpendicular to the one-dimensional lattice arrangement direction and is a vertex. In the shape of a substantially inverted isosceles triangle (wire grid type polarizing element sheet (R1)) located in the tip direction, in the cross-sectional shape in the one-dimensional grid arrangement direction and perpendicular to the sheet (A), in the shape of a continuous triangular wave . The shape of the triangular wave is a continuous substantially inverted isosceles triangle shape (wire grid type polarizing element sheet (R2)) in which the apex is located in the tip direction, or a substantially four shape in which the apex where the long sides intersect is located in the tip direction. A shape in which a square cone or a shape that gradually changes from the bottom surface of the substantially square cone toward the apex in a substantially conical shape is continuous in a one-dimensional lattice-like arrangement direction (wire grid type polarizing element sheet (R3)). ),
The polarized sunglasses lens according to (1) or (2) above.

(4) The sheet (A) is a polycarbonate resin, a polyacrylic resin, a polyamide resin, a polyester resin, a polyolefin resin, a polycycloolefin resin, a polyurethane resin, a cellulose resin, or a polyvinyl chloride resin. , A sheet selected from polyether resins, polyarylate resins, and polysulfone resins.
The polarized sunglasses lens according to any one of (1) to (3) above.
(5) The metal reflector (B) is aluminum, nickel, chromium, platinum, palladium, titanium, gold, silver, copper, or a mixture of any one or more of these alloys.
The polarized sunglasses lens according to any one of (1) to (4) above.
(6) The structure of the portion (D) in the vicinity of the tip portion of the metal reflector (B) in the thickness direction, which gradually becomes thinner toward the tip, is
In the case of the wire grid type polarizing element sheet (R1), the tip portion forms a continuous uneven shape in a one-dimensional lattice arrangement direction and in a cross-sectional shape perpendicular to the surface of the sheet (A). structure,
In the case of the wire grid type polarizing element sheet (R2), the height and wavelength of the triangular wave shape are irregularly continuous in the one-dimensional lattice arrangement direction and the cross-sectional shape perpendicular to the sheet (A). In the case of the structure or the wire grid type polarizing element sheet (R3), the length to the tip of the portion (D) that gradually becomes thinner toward the tip is approximately square, or the length of the substantially square cone. A shape that gradually changes from the bottom surface toward the apex in a substantially conical shape. The structure has a regular or irregular difference in length between the bodies, and in any of the above cases, it gradually becomes thinner toward the tip. The structure is such that the ratio (c / b) of the average length (c) of the portion (D) in the tip direction to the average thickness (b) is 0.3 or less .
The polarized sunglasses lens according to any one of (1) to (5) above.

(7) The metal reflector (B) is a metal reflector made of a calcined body of metal fine particles.
The polarized sunglasses lens according to any one of (1) to (6) above.
(8) The polarized sunglasses lens according to any one of (1) to (7) above, wherein a transparent resin layer for a lens is laminated on both the back surface side and the front surface side of the polarizing element sheet (W). ..
(9) The polarized sunglasses lens according to any one of (1) to (8) above, wherein the transparent resin layer for the lens in the polarized sunglasses lens is a layer formed by insert injection molding.
(10) The transparent resin layer for a lens formed by the insert injection molding is a polycarbonate resin, a polyamide resin, a polyester resin, a polyacrylic resin, a polyurethane resin, a cellulose resin, or a polycycloolefin resin. The polarized sunglasses lens according to (9) above, which is a layer formed of a resin selected from a resin and a polyolefin-based resin.

(11) The polarized sunglasses lens according to any one of (1) to (8) above, wherein the transparent resin layer for a lens in the polarized sunglasses lens is a layer formed by casting polymerization.
(12) The polymerizable composition used for the casting polymerization is a thiourethane-based polymerizable composition, a urethane-based polymerizable composition, a thiourea-based polymerizable composition, a urea-based polymerizable composition, or a thioepoxy-based polymerizable composition. , Epoxy-based polymerizable composition, methyl methacrylate-based polymerizable composition, aromatic carbonate-based polymerizable composition, aliphatic carbonate-based polymerizable composition, sulfide-based polymerizable composition, and episulfide-based polymerizable composition. Contains at least one polymerized product,
The polarized sunglasses lens according to (11) above.
(13) The polarized sunglasses lens according to any one of (1) to (12) above, wherein a hard coat layer is provided as an outer layer on each of the convex side and the concave side of the polarized sunglasses lens.

Since the polarized sunglasses lens of the present invention uses the wire grid type polarizing element sheet (W) as the polarizing element sheet, it does not necessarily require a protective layer or an adhesive layer, and has transparency with the transparent sheet (A). Impact resistance, heat resistance, and durability can be easily improved by selecting and combining a transparent resin for a lens. In addition, the polarized sunglasses lens of the present invention has excellent polarization performance , can maintain the required light transmittance, and can significantly reduce the reflectance of light rays incident from the back surface side. In the polarized sunglasses lens of the present invention, since the metal reflector (B) is embedded in the groove (C) of the sheet (A), the metal reflector (B) is less likely to be oxidized and has scratch resistance. Even if it is rubbed or wiped, the polarization function is not easily affected, and the surface durability is excellent.

An explanatory sectional conceptual diagram showing the wire grid type polarizing element sheet (R1) of the present invention. A conceptual diagram for explanation when the polarizing element sheet (R1) shown in FIG. 1 is viewed from diagonally above. A conceptual diagram showing an explanatory cross section of an example of the polarizing element sheet (R2) of the present invention when viewed from diagonally above. A conceptual diagram showing an explanatory cross section of an example of the polarizing element sheet (R3) of the present invention when viewed from diagonally above. Scanning electron microscope (SEM) photograph observed from diagonally above the mold used in Example 1. SEM photograph observed from diagonally above the mold used in Example 1. SEM photograph observed from diagonally above the polarizing element sheet (R1) test piece produced in Example 1. SEM photograph observed from diagonally above the front of the mold used in Example 4. SEM photograph observed from the right side of the front of the mold used in Example 6. SEM photograph observed from diagonally above the front of the mold used in Example 8. SEM photograph observed from diagonally above the front of the mold used in Comparative Example 2.

The polarized sunglasses lens of the present invention is a polarized sunglasses lens in which a transparent resin layer for a lens is laminated on at least one of the back surface side and the front surface side of the wire grid type polarizing element sheet (W). There,
The polarizing element sheet (W) uses a transparent sheet (A) as a base material, and a metal reflector is formed on a large number of grooves (C) provided on the surface thereof in a one-dimensional lattice pattern in the same direction and at the same period. The average width (a) of the metal reflector (B) excluding the portion (D) in which (B) is embedded and gradually becomes thinner toward the tip below (hereinafter, simply "average width (a)). ”) Is 200 nm or less,
The ratio (b / a) of the average thickness (b) of the metal reflector (B) from the front surface side to the tip end in the back surface direction and the average width (a) is in the range of 4 to 25.
In addition, at least one of the cross-sectional shapes parallel to and perpendicular to the one-dimensional lattice arrangement direction near the tip of the metal reflector (B) in the thickness direction becomes linear or smooth curved and gradually narrows toward the tip. The ratio (c / a) of the average length (c) to the average width (a) of the portion (D) that gradually becomes thinner toward the tip is 1.2 or more. It is characterized by that.

In the present invention, the shape of the metal reflector (B) is not so-called "wire-shaped", but the term "wire grid polarizing element" is used even when the metal reflector is not wire-shaped in the technical field. Therefore, the term wire grid type polarizing element is used.
FIG. 1 is a cross-sectional view schematically shown for explaining the wire grid type polarizing element sheet 1 of the present invention. The sheet (A) 11 has a front surface side 12 and a back surface side 13, and the front surface thereof is shown. A metal reflector (B) 14 is embedded in the side 12. The metal reflector (B) 14 has a portion (D) 15 that gradually becomes thinner toward the tip. In FIG. 1, the average width (a), the average thickness (b), the average length (c) of the portion (D) 15 that gradually becomes thinner toward the tip, and the period (d) are displayed by other methods. It is also used in common in the form.

FIG. 2 is a conceptual diagram for explanation that schematically shows the wire grid type polarizing element sheet (R1) 2, and the shape of the portion (D) 15 that gradually becomes thinner toward the tip is a one-dimensional grid. It is a cross-sectional shape perpendicular to the arrangement direction, and is a shape of a substantially inverted isosceles triangle whose vertices are located in the tip direction. FIG. 3 is an example of an explanatory cross-sectional view schematically showing the wire grid type polarizing element sheet (R2) 3, and the shape of the portion (D) 17 that gradually becomes thinner toward the tip is primary. The shape of the triangular wave is continuous in the cross-sectional shape in the original grid-like arrangement direction and perpendicular to the sheet (A), and the shape of the triangular wave is the shape of a continuous substantially inverted isosceles triangle in which the apex is located in the tip direction. FIG. 4 is an example of an explanatory cross-sectional view schematically showing a wire grid type polarizing element sheet (R3), and the shape of the portion (D) 19 that gradually becomes thinner toward the tip is a long side. It is a shape in which substantially quadrangular pyramids whose vertices intersect with each other are located in the tip direction and are continuous in the one-dimensional lattice arrangement direction.
Since FIGS. 5 to 11 are scanning electron microscope (SEM) photographs of the mold and the like used in the examples of the present specification, these photographs will be described in the examples.
Hereinafter, the present invention will be described separately for [1] a wire grid type polarizing element sheet (W) and [2] a polarized sunglasses lens using the polarizing element sheet (W).

[1] Wire grid type polarizing element sheet (W)
The wire grid type polarizing element sheet (W) constituting the polarizing element of the polarized sunglasses lens of the present invention is
A transparent sheet (A) is used as a base material, and a metal reflector (B) is embedded in a large number of grooves (C) provided on the surface thereof in a one-dimensional lattice pattern in the same direction and at the same period. hand,
The average width (a) of the metal reflector (B) excluding the portion (D) that gradually becomes thinner toward the tip is 200 nm or less.
The ratio (b / a) of the average thickness (b) of the metal reflector (B) from the front surface side to the tip end in the back surface direction and the average width (a) is in the range of 4 to 25.
In addition, at least one of the cross-sectional shapes parallel to and perpendicular to the one-dimensional lattice arrangement direction near the tip of the metal reflector (B) in the thickness direction becomes linear or smooth curved and gradually narrows toward the tip. The ratio (c / a) of the average length (c) to the average width (a) of the portion (D) that gradually becomes thinner toward the tip is 1.2 or more. It is characterized by that.

(1) Sheet (A) (1-1) Surface shape of sheet (A) Generally, when the thickness is 250 μm or less, it may be distinguished as a film, and when the thickness is more than 250 μm, it may be distinguished as a sheet. Can be used for both sheets and films without distinguishing between them. Therefore, in the present specification, the sheets and films are collectively referred to as sheets.
The surface shape of the sheet (A) is preferably flat from a practical point of view, and may be curved with a gentle curvature. Such a sheet (A) can easily form a groove (C) on the surface of the sheet (A) by a nanoimprint method or the like, and can easily perform a post-treatment step such as coating. Further, if the outer surface of the metal reflector (B) is substantially flush with the surface of the sheet (A) and is embedded in the groove portion (C), it has scratch resistance and has a polarization function even when rubbed or wiped. Is unlikely to affect.

(1-2) Material of Sheet (A) The "transparent sheet (A)" used as the base material of the wire grid type polarizing element sheet (W) of the present invention is intended for the visible light region and the infrared region. Both organic and inorganic materials are used as long as the sheet has transparency in electromagnetic waves of wavelength and it is possible to form a one-dimensional lattice-shaped (striped) groove portion described later on the surface of the sheet (A). It is possible.
The transparent sheet (A) means a colorless or colored sheet, including a transparent and translucent sheet, and having a light transmittance of 8% or more at a wavelength in the visible light region.
The colored sheet (A) is, for example, a method of blending a masterbatch containing a colorant and kneading in a molten state in the case of an organic material, coloring by ion addition in the case of an inorganic material, and a nanometer-sized colloid. The translucent sheet (A) can be obtained by, for example, melting and kneading two resins having different refractive coefficients to control the haze value.

The organic materials that can be used include polycarbonate resin, polyacrylic resin, polyamide resin, polyester resin, polyolefin resin, polycycloolefin resin, polyurethane resin, cellulose resin, polyvinyl chloride resin, and poly. The use of ether-based resins, polyarylate-based resins, and polysulfon-based resins is preferable, but is not limited to these.
If polycarbonate or the like is used as the sheet (A), heat resistance, impact resistance, etc. can be improved, but coloring interference fringes are generated on the side where sunlight is incident and the degree of polarization when viewed from the transmission side. There is a problem of decline. As a means for solving this problem, when a polycarbonate sheet is obtained by extrusion molding or the like, it is preferable to stretch it in one direction to control the retardation value (the product of the birefringence index and the thickness of the sheet). The retardation value is not particularly limited, but a very low value or a high value is preferable, and in the case of a high value, the drawn shaft of the sheet (A) as the base material becomes the absorption shaft of the wire grid type polarized light. It is preferable to make it vertical to the vertical.

Examples of the inorganic material that can be used include, but are not limited to, glass, silicon, quartz, and ceramic materials.
Among the above materials, the use of an organic material is more preferable in consideration of processability such as formation of a groove (C). Further, the sheet (A) is preferably a single layer in consideration of expansion and contraction processes such as bending, but may be a plurality of layers.

(1-3) Shape of Groove (C) in Sheet (A) The groove (C) formed in the sheet (A) is formed to embed the metal reflector (B). Since the shape of the metal reflector (B) is formed by forming the shape of the groove portion (C) almost as it is, the shape of the groove portion (C) is the same as that of the metal reflector (B). In the section of the shape, the method of manufacturing the groove (C) shape will be described in the section of the method of manufacturing the wire grid type polarizing element sheet (W).

(2) Metal Reflector (B) (2-1) Material of Metal Reflector (B) The material of the metal reflector (B) used in the present invention reflects light in the wavelength range of the light to be used. Any metal material having a function can be used without particular limitation, and specific examples thereof include aluminum, nickel, chromium, platinum, palladium, titanium, gold, silver, copper, and alloys thereof, which are highly reflective metal materials. Examples thereof include a mixture of any one or more of the above, molybdenum, tungsten, tantalum, zirconium, iron, niobium, hafnium, cobalt and the like, which are low-reflection metal materials, and alloys thereof. Among these, the use of a highly reflective metal material is preferable in consideration of the polarization property. Further, when the metal reflector (B) is formed by using a metal fine particle firing means or a plating means, it is desirable to select the metal reflector (B) in consideration of these processing means.

(2-2) Shape and Structure of Metal Reflector (B) The shape of the metal reflector (B) in the wire grid polarizing element sheet (W) of the present invention has the same orientation as the surface of the transparent sheet (A). Moreover, the metal reflectors (B) are provided in a one-dimensional grid pattern with the same period, have an average width (a) of 200 nm or less, and have an average thickness (b) of the metal reflector (B) from the front surface side to the front end in the back surface direction of the sheet (A). The ratio (b / a) of the average width (a) is in the range of 4 to 25, and at least one of parallel and perpendicular to the one-dimensional lattice arrangement direction near the tip of the metal reflector (B) in the thickness direction. The average length (c) of the portion (D) in which one of the cross-sectional shapes gradually becomes thinner toward the tip and is linear or smooth curved, and gradually becomes thinner toward the tip. ) And the ratio (c / a) of the average width (a) is 1.2 or more.

In order to exert polarization performance for light of the wavelength to be used, each metal reflector (B) in the groove portion (C) of the sheet (A) is first-ordered on the surface of the sheet (A) in the same direction and at the same period. It needs to be arranged in the original grid pattern (striped pattern). Since the metal reflector (B) has the shape and structure described below and is embedded in the groove (C) of the sheet (A), it is scratch resistant and does not affect the polarization function even if it is rubbed or wiped. It is hard to come out and has excellent surface durability. Further, since the metal reflector (B) is covered with the groove structure of the sheet (A), the exposed portion from the surface can be reduced, and as a result, the metal reflector (B) is less likely to be oxidized, and can be used outdoors or outdoors. The polarization performance can be maintained for a long time even in a high temperature and high humidity environment.
(I) Average width (a) of the metal reflector (B)
The average width (a) of each metal reflector (B) of the present invention is 200 nm or less in consideration of the degree of polarization and the light transmittance, and is preferably 25 to 100 nm. Even for electromagnetic waves in wavelength regions other than the visible light region, such as the ultraviolet region, near-infrared region, infrared region, terahertz region, and microwave region, it is preferable that the wavelength is about 1/16 to 1/4 of the wavelength of the electromagnetic wave for the groove width. It has been known.

(Ii) Period of one-dimensional lattice arrangement of metal reflector (B) (c)
The period (c) of the one-dimensional lattice arrangement can be determined by the wavelength of the light intended to be polarized by the wire grid type polarizing element. For example, the period (c) is 1/5 or less to 1 of the wavelength of the intended light. It can be about / 2 or less. On the other hand, considering the transmittance of the light incident on the wire grid type polarizing element from the surface side, the larger the period (d) with respect to the average width (a), the higher the light transmittance, so that the metal reflector The ratio (d / a) of the period (d) of the one-dimensional lattice-like arrangement (B) to the average width (a) is preferably 1 to 10, and further, considering the balance with the degree of polarization, 2 to 2. 5 is more preferable.

(Iii) Average thickness (b) of the metal reflector (B)
The ratio (b / a) of the average thickness (b) to the average width (a) of the metal reflector (B) from the front surface side to the tip end in the back surface direction of the sheet (A) is 4 to 25. When the ratio (b / a) is 4 or more, the degree of polarization is improved, and it is 25 or less in consideration of mold processing, light transmittance and the like, and 7 to 20 is preferable from a practical point of view.
In the wire grid type polarizing element sheet (W) of the present invention, in order to improve the degree of polarization of light incident from the surface side, the average thickness (b) of the metal reflector (B) can be increased as described above. It is one of the features.

(Iv) The average length (c) of the portion (D) that gradually becomes thinner toward the tip.
In the wire grid type polarizing element sheet (W) of the present invention, the ratio (b / a) of the average thickness (b) and the average width (a) of the metal reflector (B) is set in the range of 4 to 25. In order to improve the degree of polarization and reduce the reflectance on the back surface side, at least one cross section parallel to or perpendicular to the one-dimensional lattice arrangement direction in the vicinity of the tip portion in the thickness direction of the metal reflector (B). The average length (c) and the average width of the portion (D) that gradually becomes thinner toward the tip and becomes linear or smooth curved toward the tip. A further feature is that the ratio (c / a) of (a) is 1.2 or more.

By setting the ratio (c / a) of the average length (c) of the portion (D) that gradually becomes thinner toward the tip to the average width (a) in the tip direction to 1.2 or more, the back surface is set. It becomes possible to reduce the reflectance from the side. Considering the workability of the mold and the like, the ratio (c / a) is preferably 1.2 to 8 and more preferably 2 to 5.

(V) Three-dimensional shape of the portion (D) that gradually becomes thinner toward the tip The shape of the portion (D) that gradually becomes thinner toward the tip in the vicinity of the tip portion in the thickness direction of the metal reflector (B). (Hereinafter, it may be referred to as "the shape of the tip that becomes thinner") is a straight line or a smooth curve so that at least one of the cross-sectional shapes parallel to and perpendicular to the one-dimensional lattice arrangement direction goes to the tip. It is a shape that gradually becomes thinner.
Such a shape is not particularly limited as long as it can be formed by selecting from a polygonal prism, a polygonal pyramid, or a three-dimensional shape of a combination thereof, but preferred specific examples are as follows (v-1) to (v-3). show.

(V-1) Wire grid type polarizing element sheet (R1)
A portion (D) of the wire grid type polarizing element sheet (R1) 2 that gradually becomes thinner toward the tip of the metal reflector (B) 14 as schematically shown in FIG. 2 and a conceptual diagram for explanation. The shape of 15 is a substantially inverted isosceles triangle whose apex is located in the tip direction in the vicinity of the tip portion of the cross-sectional shape perpendicular to the one-dimensional lattice arrangement direction.
(V-2) Wire grid type polarizing element sheet (R2)
A portion (D) of the wire grid type polarizing element sheet (R2) 3 that gradually becomes thinner toward the tip of the metal reflector (B) 16 as shown in the schematic sectional view of FIG. The shape of 17 is a continuous triangular wave shape in a one-dimensional lattice arrangement direction and a cross-sectional shape perpendicular to the sheet (A), and the triangular wave shape is a continuous substantially inverted isosceles triangle whose apex is located in the tip direction. The shape of. In FIG. 3, in order to distinguish it from the shape shown in FIG. 4, the shape of the triangular wave is shown three-dimensionally by extracting it as A'as an enlarged view of the A portion. The wave portion of the triangular wave shape wave has a gable roof shape, but the gable roof shape can be transformed into a hipped roof shape.

(v-3) Wire grid type polarizing element sheet (R3)
A portion (D) of the wire grid type polarizing element sheet (R3) 4 that gradually becomes thinner toward the tip of the metal reflector (B) 18 as shown in the schematic cross-sectional view of FIG. The shape of 19 is a substantially quadrangular pyramid whose vertices whose long sides intersect are located in the tip direction, or a one-dimensional lattice in which a shape gradually changes into a substantially conical shape from the bottom surface of the substantially quadrangular pyramid toward the apex. It is a shape that is continuous in the shape arrangement direction. In FIG. 4, in order to distinguish it from the shape shown in FIG. 3, a substantially quadrangular pyramid is shown three-dimensionally by extracting it as B'as an enlarged view of the B portion.
In any of the shapes shown in (v-1) to (v-3), the average length (c) of the narrowing portion (D) in the tip direction and the average thickness of the metal reflector (B). Since the ratio (c / a) to and to is 1.2 or more, preferably 1.2 to 8, the apparent angle of the cutting edge is within a common range, and therefore the reflection of incident light from the back surface side. Both rates will decline.

(Vi) Shape of the tip of the portion (D) that gradually becomes thinner toward the tip The portion (D) that gradually becomes thinner toward the tip in the vicinity of the tip of the metal reflector (B) in the thickness direction. The structure of
In the case of the wire grid type polarizing element sheet (R1), the tip portion forms a continuous uneven shape in a one-dimensional lattice arrangement direction and in a cross-sectional shape perpendicular to the surface of the sheet (A). structure,
In the case of the wire grid type polarizing element sheet (R2), the height and wavelength of the triangular wave shape are irregularly continuous in the cross-sectional shape in the one-dimensional lattice arrangement direction and perpendicular to the sheet (A). structure,
Or, in the case of the wire grid type polarizing element sheet (R3), the length to the tip of the portion (D) that gradually becomes thinner toward the tip is approximately square from the bottom of each approximately square pyramid. A structure that has a regular or irregular difference in length between shapes that gradually change in a substantially conical shape toward the apex.
Moreover, in any of the above cases, it is preferable that the length of the portion (D) that gradually becomes thinner toward the tip in the tip direction is 0.3 times or less the average length (b). .. By changing the length of the tip portion of the portion (D) that gradually becomes thinner toward the tip end, the reflectance on the back surface side can be further reduced.

(Vii) Structure in the groove (C) of the metal reflector (B) A vapor deposition method or a sputtering method is known as a method for forming a film of an absorption type wire grid polarizing element. As a method for manufacturing an element, a metal reflector (B) is formed in a lattice-shaped groove provided in a transparent sheet (A) by using a plating means or a means for firing an ink containing metal fine particles. In particular, it is preferable that the metal reflector (B) is a metal reflector made of a fired metal fine particle by using a means for firing an ink containing metal fine particles as described later.

The metal reflector (B) has an average width (a), an average thickness (b), and a portion (D) that gradually becomes thinner toward the tip in the groove portion (C) toward the tip. It is embedded in the shape of the average length (c), but may be further embedded in the groove (C) as a single continuous structure in each groove (C), or in the form of a plurality of blocks. The structures are embedded in the groove (C) in a state of being laminated at a high density, and each block-shaped structure is laminated in an independent state from each other, or a part of the outer surface of each block-shaped structure. May be laminated in a state where they are joined.
When the metal reflector (B) is formed by the plating means, the single continuous structure can be formed, and when the metal fine particles are fired by the firing means, the plurality of blocks are formed by controlling the firing conditions. In the groove portion (C), the block-shaped structures are laminated independently of each other, or a part of the outer surface of each block-shaped structure is joined to form a laminated state. be able to.

(3) Manufacturing Method of Wire Grid Type Polarizing Element Sheet (W) The wire grid type polarizing element sheet (W) is provided on the surface of the transparent sheet (A) in the same direction and in the same period in a one-dimensional lattice pattern. It can be manufactured by forming a large number of grooves (C) and then embedding a metal reflector (B) in the grooves (C). For the formation of the groove portion (C), it is possible to use an exposure technique such as nanoimprint method, injection molding, electron beam lithography, focused ion beam, interference exposure, self-assembly technique using nanoparticles and the like. Further, as a means for embedding the metal reflector (B) in the groove portion (C), a means for firing metal fine particles, a plating means, a physical vapor deposition method, a chemical vapor deposition method, or the like can be used.
Below, as a specific example of a simpler method, after forming a fine groove portion (C) on the surface of the transparent sheet (A) using the nanoimprint method, firing of metal fine particles in the groove portion (C). Regarding the method for manufacturing the wire grid type polarizing element sheet (W) in which the metal reflector (B) is embedded by means, the groove portion (C) forming step (first step) and the metal reflection to the groove portion (C). The process of embedding the body (B) (second step) will be described separately.

(3-1) First step (step of forming a groove (C) on the surface of the sheet (A))
The first step is a step of forming a large number of grooves (C) on the surface of the transparent sheet (A) in a one-dimensional lattice pattern in the same direction and at the same period by the nanoimprint method, and the grooves (A) are formed on the sheet (A). In the mold used for forming C), the structure of each convex portion forming the groove portion (C) has the same shape as the metal reflector (B) of the wire grid type polarizing element sheet (W). Since it has, the description here is omitted.

In the nanoimprint method in which the groove portion (C) is formed on the surface of the sheet (A) in the first step, even a minute uneven structure of about several tens of nm formed on a mold having the above shape by using a press device can be processed. Copy (imprint) to the sheet (A). Silicon is preferable as the material of the mold, but glass such as quartz, ceramics such as alumina and silicon carbide, and nickel having a certain strength are used. The mold can be manufactured by using the above-mentioned materials and utilizing a semiconductor or photomask manufacturing technique.

The nanoimprint method uses thermal nanoimprint in which the sheet (A) is a thermoplastic resin or glass, and photocurable nanoimprint in which the material to be processed is a photocurable resin, and the microstructure of the mold is inverted as it is. Can be copied to the transfer target. In the nanoimprint method, it is preferable to use a fluorine-based mold release agent as the mold release agent applied to the mold, while a silicon-based mold release agent is used depending on the mold (mold) material or the resin material to be molded. Can also be used.

(3-2) Second step (step of embedding the metal reflector (B) in the groove (C))
The step of embedding the metal reflector (B) is a step of filling the groove (C) of the transparent sheet (A) with an ink or a paste containing metal fine particles (hereinafter, the ink and the paste are collectively referred to as ink) (ink). The filling step) and the step of heating the filled ink to firing the metal fine particles.
(I) Ink filling step The ink has an average particle size of a metal reflector (B) in a solvent containing at least an amine compound that coats the surface of fine metal particles, a dispersant such as gelatin, and an organic solvent having a high boiling point. An ink in which metal fine particles having an average width (a) or less, preferably 1/2 or less of the average width (a) are uniformly dispersed, and the metal fine particles content in the ink is about 60 to 90% by mass. It is desirable to use.

Since the inks that can be used in the present invention are commercially available as shown in Examples, they are easily available. The metal fine particles are the same as the constituent materials of the metal reflector (B), and are a mixture of aluminum, nickel, chromium, platinum, palladium, titanium, gold, silver, copper, and any one or more of these alloys. It is preferably a body. The ink containing the above components can draw a fine pattern, and when the metal fine particles are heated and fired, the dispersant such as an amine compound is separated from the surface of the metal fine particles to promote firing.

Since the width of the groove portion (C) is nano-sized, it is possible to fill the groove portion (C) of the sheet (A) by utilizing the capillary phenomenon. Further, it is desirable to form a liquid-repellent film on the surface of the sheet (A). The liquid-repellent film not only promotes filling of the ink in the groove (C), but also functions as a protective film for preventing the fired metal fine particles from adhering to unnecessary parts on the sheet (A). do. As a method for filling the groove (C) of the ink, a method using a squeegee, a doctor blade, or the like is preferable. In order to selectively remove the excess ink remaining on the surface of the sheet (A) after filling the groove (C) with ink, a method of directly wiping the surface of the sheet (A) is preferable.

(Ii) Firing step of metal fine particles The sheet (A) in which the groove (C) is filled with ink is heated to evaporate the dispersant and the organic solvent contained in the ink, and the metal fine particles are fired. , Is a step of forming a metal reflector (B) in the groove portion (C). In order to control the firing degree of the metal fine particles, it is preferable to use a heating oven, but a firing device such as a hot plate, a plasma firing device, a microwave firing device, a flash lamp light firing device, or a laser firing device should be used. Is also possible.
The firing temperature and the time required for firing depend on the components of the metal fine particles, the particle size, the dispersant used for the ink, and the organic solvent, but the firing temperature is generally preferably 80 to 200 ° C., more preferably 100 to 160 ° C. Is. The firing time can be arbitrarily determined in consideration of the firing temperature.
When the liquid-repellent film is formed on the surface of the sheet (A), the liquid-repellent film can be peeled off after the firing to obtain the wire grid type polarizing element sheet (W) of the present invention.

[2] Polarized Sunglasses Lens In the polarized sunglasses lens of the present invention, a transparent resin layer for a lens is laminated on at least one of the back surface side and the front surface side of the wire grid type polarizing element sheet (W). It is a polarized sunglasses lens.
By using the wire grid type polarizing element sheet (W) for the polarized sunglasses lens of the present invention, a protective layer, an adhesive layer adhesive, an adhesive layer, etc. are not always required, the degree of polarization is excellent, and the required light transmittance is obtained. It can be maintained, the reflection from the back surface side (eyepiece side) can be reduced, and excellent visibility can be obtained.

As described above, the polarized sunglasses lens of the present invention using the wire grid type polarizing element sheet (W) is different from the polarized sunglasses lens using the absorption type polarizing element film, and has a protective layer, an adhesive layer, and an adhesive layer. The transparent lens resin can be directly fused to at least one of the back surface side and the front surface side of the polarizing element sheet (W) by using a mold or the like without using the above.
The means for laminating a transparent resin layer for a lens on at least one of the back surface side and the front surface side of the polarizing element sheet (W) is not particularly limited, but a practical molding method will be described below. Injection molding of thermoplastic resin and cast polymerization of curable resin can be mentioned.
The transparent lens resin layer includes a colorless or colored, transparent and translucent lens resin layer, as described in the section of the transparent sheet (A). It means a resin layer for a lens having a light transmittance of a wavelength of 8% or more in the visible light region. The colored resin layer for lenses and the semi-transparent resin layer for lenses are the same as those described in the colored sheet (A) and the translucent sheet (A).

(1) Polarized Sunglasses Lens Molded by Injection Molding A polarized sunglasses lens can be molded by fusing a transparent resin layer for a lens to a polarizing element sheet (W) by injection molding. A known method can be adopted as the injection molding method, but as a specific example of the process, first, an unnecessary portion of the polarizing element sheet (W) is removed, and then bending processing is performed into a lens shape, and the gold of the injection molding machine is used. Polarized sunglasses lens that is mounted in the mold, then heated molten resin is injected onto one side (or both sides) of the lens-shaped polarizing element in the mold, fused with the lens-shaped polarizing element sheet, and molded after cooling the mold. There is a method of taking out the lens from the mold.

As a specific example of the bending process to the lens shape, there is a processing method for producing a predetermined curved spherical surface shape by hot pressing, vacuum compressed air pressing, etc. on the polarizing element sheet (W) in which unnecessary parts are removed by punching or the like. Can be mentioned.
Further, as a specific example of the injection molding, the bending process is performed by using an insert injection molding machine provided with a concave movable side mold having a curvature of the spherical shape and a convex fixed side mold having an arbitrary curvature. The pattern surface side (front side) of the polarizing element piece of the spherical shape obtained in 1 is set and fixed to the concave movable side mold, and the fixed side mold is tightened to the movable side mold, and then has transparency. A method of injecting a resin for a lens between a polarizing element piece and a fixed-side mold and heat-adhering a transparent resin layer for a lens to the back surface side to obtain a transparent polarized sunglasses lens having a predetermined thickness and curved surface. Can be mentioned. Depending on the purpose, the pattern surface side of the polarizing element may be in close contact with the convex fixed side mold, and the back surface side may be arranged so as to face the concave movable side mold.
In order to prevent scratches on the lens surface, it is preferable to provide a hard coat layer as an outer layer on each of the convex side and the concave side of the polarized sunglasses lens, but the formation of the hard coat film is not particularly limited, for example, heat. A hard coat having curability, ultraviolet curability, etc. can be used.

The transparent resin layer for lenses formed by the insert injection molding is a layer formed of a thermoplastic resin. Among the thermoplastic resins, a polycarbonate resin, a polyamide resin, a polyester resin, and a poly A layer formed of a resin selected from an acrylic resin, a polyurethane resin, a cellulose resin, a polycycloolefin resin, and a polyolefin resin is preferable.
Further, as described above, the transparent sheet (A) used when producing the polarizing element sheet (W) is a polycarbonate resin, a polyacrylic resin, a polyamide resin, a polyester resin, or a polyolefin resin. It is desirable to select from a resin, a polycycloolefin resin, a polyurethane resin, a cellulose resin, a polyvinyl chloride resin, a polyether resin, a polyarylate resin, and a polysulfone resin.

Therefore, when selecting a transparent resin layer for a lens, the melting temperature between the resin forming the sheet (A) and the resin forming the resin layer for the lens, the solubility parameter (Sp value), and the like are taken into consideration. Therefore, it is necessary to consider the combination of resins and the like so that a transparent resin layer for lenses can be obtained. Since the melting temperature, Sp value, etc. of each thermoplastic resin are known, the reflectance on the back surface side can be reduced by selecting a preferable combination of the sheet (A) and the resin for lenses, for example, a combination of polycarbonates. Not only can it be possible, but also polarized sunglasses having excellent impact resistance, heat resistance, and durability can be obtained.

(2) Polarized sunglasses lens molded by casting polymerization A polarized sunglasses lens is a polarizing element that is formed by injecting a polymerizable liquid material into a molding mold in which a polarizing element sheet (W) is set by casting polymerization, and then polymerizing and curing the material. A transparent resin layer for a lens can be laminated on at least one surface of the sheet (W) to form the sheet (W). The cast polymerization has a feature that restrictions on the base material of the polarizing element sheet can be relaxed and delamination between layers in the polarized sunglasses lens can be suppressed.

Various proposals have been made for molds and polymerizable liquid materials in the cast polymerization method. As one specific example, first, a set of two molds, one on the lower side and the other on the upper side having a predetermined curvature on the surface, is prepared, and on the other hand, a polymerizable liquid material is mixed. The polarizing element sheet (W) is subjected to curvature processing to a predetermined curvature by vacuum forming or the like, and then a shaped polarizing sheet is formed by circular press punching or the like, and the shaped polarizing sheet is formed into a set of the above two sheets. After setting between the molds, the tape is wound around the mold while keeping the center spacing constant to adjust the mold, and then the polymerized liquid material prepared in the mold is injected and heated at a predetermined temperature. A method of molding a polarized sunglasses lens by polymerizing and curing the polymerizable liquid material. The polarized sunglasses lens obtained by casting polymerization is shaped as necessary. Further, it is preferable to provide a hard coat layer as an outer layer on each of the convex side and the concave side of the polarized sunglasses lens by the above-mentioned forming means.

As the polymerizable composition used for the casting polymerization, various compositions have been proposed, but a thermosetting resin that can be generally used for the casting polymerization can be used. Preferred polymerizable compositions include thiourethane-based polymerizable compositions, urethane-based polymerizable compositions, thiourea-based polymerizable compositions, urea-based polymerizable compositions, thioepoxy-based polymerizable compositions, and epoxy-based polymerizable compositions. Containing at least one selected from a product, a methyl methacrylate-based polymerizable composition, an aromatic carbonate-based polymerizable composition, an aliphatic carbonate-based polymerizable composition, a sulfide-based polymerizable composition, and an episulfide-based polymerizable composition. Examples thereof include polymerizable compositions. In addition to the polymerizable monomer, a curing agent, a mold release agent, an ultraviolet absorber, or the like can be added to the polymerizable composition.

Further, as described above, the transparent sheet (A) used when producing the polarizing element sheet (W) is a polycarbonate resin, a polyacrylic resin, a polyamide resin, a polyester resin, or a polyolefin resin. A transparent lens because it is desirable to select from a resin, a polycycloolefin resin, a polyurethane resin, a cellulose resin, a polyvinyl chloride resin, a polyether resin, a polyarylate resin, and a polysulfone resin. In selecting the resin for use, it is necessary to consider the combination of resins and the like so that a transparent resin layer for lenses can be obtained after casting polymerization.

An antireflection film can be formed as an outer layer on one side or both sides of the polarized sunglasses lens molded by injection molding or casting polymerization, and an antireflection film is used as an outer layer on the convex side and an antireflection film is used as an outer layer on the concave side. Can be formed. If a hard coat layer is provided as an outer layer on each of the convex and concave sides of the polarized sunglasses lens after the injection molding or casting polymerization, an antireflection film is further formed on one or both sides thereof as the outermost layer. Further, an antireflection film can be formed on the convex side thereof and an antireflection film can be formed on the concave side as the outermost layer.

Next, Examples and Comparative Examples performed for clarifying the present invention will be described. First, a wire grid type polarizing element was manufactured and evaluated, and then polarized sunglasses were prototyped and evaluated using the manufactured polarizing element. In the following Examples 1 to 12, the polarizing element sheet may be referred to as a polarizing element. The present invention is not limited to the following examples.
1. 1. Fabrication and evaluation of wire grid type polarizing element test piece The polarization degree, light transmittance, and light reflectance of the prepared test piece were measured using the following devices.

(i) Measurement of polarization and light transmittance A spectrophotometer (model: SolidSpec-3700) manufactured by Shimadzu Corporation was used.
The incident light of the electric field component vibrating in the parallel direction and the vertical direction was used for the metal reflector embedded in the produced polarizing element, and the incident light of random polarization was used in the reflectance measurement. The polarization characteristics were evaluated based on the degree of polarization. Assuming that the visible transmittance when the polarized light is parallel to the metal reflector is Tp and the visible transmittance when the polarized light is perpendicular to the metal reflector is Tv, the degree of polarization V is V = √ ((Tv-Tp). ) / (Tv + Tp)). The luminosity factor for each of the polarizations can be obtained from the respective transmittances (transmission spectra) and the luminosity factor curves at wavelengths of 380 to 780 nm (in increments of 1 nm).
(Ii) Measurement of light reflectance A spectrophotometer (model: USPM-RUIII) manufactured by Olympus Corporation was used.
The visual transmittance T can be obtained from T = (Tv + Tp) / 2. Since the visual reflectance R in the case of reflectance is random polarization, a value obtained from the reflection spectrum and the luminosity factor curve was used.

(Examples 1, 2, 3)
A fine groove structure is formed on the surface of the thermoplastic resin sheet by a thermal nanoimprint method using a mold, and then the groove is filled with an ink containing silver fine particles, and then silver contained in the ink is placed in a heated oven. A polarizing element in which fine particles are fired and the wire grid type polarizing element (R1) type has an irregularly continuous uneven shape at the cutting edge in a one-dimensional lattice arrangement direction and perpendicular to the sheet surface. A test piece was prepared.

(1) Formation of a fine groove structure on the sheet surface A polycarbonate sheet (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name: FE-2000, thickness: 400 μm) was used as the sheet. The mold used was a 4-inch silicon wafer that had been microfabricated. The microstructure of the mold used has an inverted shape of the groove shape formed in the wire grid type polarizing element (R1) type, and the convex portion shape forming the groove portion has an average width (a') and an average. The thickness (b'), the average length (c') of the portion ( D' ) that gradually becomes thinner toward the tip, and the period (d') of the arrangement are as shown in Table 1. Further, the cross section of the tip portion in the one-dimensional lattice arrangement direction and perpendicular to the sheet surface has an irregularly continuous uneven shape, and the height difference of the uneven shape is 100 nm in Example 1, Example. In both cases , the length (c') in the tip direction of the portion ( D' ) that gradually becomes thinner toward the tip is the average length (b'). It was a mold that was within 0.3 times that of. Using each of these molds, the fine groove structure was transferred to the sheet surface by the thermal nanoimprint method. FIG. 5 is a scanning electron microscope (SEM) photograph observed from diagonally above the mold used in Example 1, and FIG. 6 is a scanning electron microscope (SEM) photograph observed from diagonally above the mold used in Example 1. ..

(2) Filling the fine grooves of the sheet with ink By the squeezing method, silver nano ink (trade name: NPS, silver fine particle content: 85% by mass, average particle diameter: 12 nm) manufactured by Harima Chemicals, Inc. is placed in the grooves. Filled into. Then, by wiping, the excess ink adhering to the area other than the inside of the groove was removed.
(3) Preparation of Polarizing Element by Firing The sheet filled with the ink in the groove is placed in an oven heated to 130 ° C. for 12 hours in Example 1, 81 hours in Example 2, and 12 hours in Example 3. The silver fine particles contained in the ink were fired to prepare a test piece for a polarizing element.

(4) Evaluation Results The degree of polarization, light transmittance, and light reflectance of the obtained wire grid type polarizing element test piece were measured. These results are summarized in Table 1. Good results were obtained for both the degree of polarization and the reflectance on the back surface side. Further, FIG. 7 shows a scanning electron microscope (SEM) photograph from the upper surface side of the obtained wire grid type polarizing element test piece. It was confirmed that silver nanoparticles grown to a size of several tens of nm were lined up along the groove at the upper part of the groove. It was also confirmed that silver nanoparticles grown to about 100 nm overlapped inside the groove, and a pattern composed of silver particles having a size distribution was formed inside the groove.

(Examples 4, 5 and 6)
A fine groove structure is formed on the surface of the thermoplastic resin sheet by a thermal nanoimprint method using a mold, and then the groove is filled with an ink containing silver fine particles, and then silver contained in the ink is placed in a heated oven. A polarizing element test piece obtained by firing fine particles and having a wire grid type polarizing element (R1) type having a one-dimensional lattice-like arrangement direction and a substantially linear cross section at the most advanced portion perpendicular to the sheet surface. Made.

(1) Preparation of Polarizing Element Test Piece A sheet similar to that used in Example 1 was used. The microstructure of the mold used has an inverted shape of the groove shape formed in the wire grid type polarizing element (R1) type, and the convex portion shape forming the groove portion has an average width (a'). The average thickness (b'), the average length (c') of the portion ( D' ) that gradually becomes thinner toward the tip, and the period (d') of the arrangement are as shown in Table 1. be. Using each of these molds, the fine groove structure was transferred to the sheet surface by the thermal nanoimprint method. FIG. 8 is a scanning electron microscope (SEM) photograph observed from diagonally above the front of the mold used in Example 4, and FIG. 9 is a scanning electron microscope (SEM) photograph observed from the right side of the mold used in Example 6. Is.

Then, by the squeezing method, the same silver nano ink used in Example 1 was filled in the groove portion, and after filling, the excess ink adhering to other than the inside of the groove portion was removed by wiping.
Next, the sheet filled with the ink in the groove was fired for 12 hours together in an oven heated to 130 ° C. to prepare a polarizing element test piece.
(2) Evaluation Results The degree of polarization, light transmittance, and light reflectance of the obtained polarizing element test piece were measured. These results are summarized in Table 1. In Examples 4 and 5, good results were obtained in both the degree of polarization and the reflectance on the back surface side. Further, in Example 6, it was confirmed that the ratio (b / a) of the average thickness (b) of the metal reflector and the average width (a) was 4.4 , and the degree of polarization was improved.

(Examples 7, 8 and 9)
A fine groove structure is formed on the surface of the thermoplastic resin sheet by a thermal nanoimprint method using a mold, and then the groove is filled with an ink containing silver fine particles, and then silver contained in the ink is placed in a heated oven. The fine particles were fired to produce a polarizing element test piece of the wire grid type polarizing element (R3) type.

(1) Preparation of Polarizing Element Test Piece A sheet similar to that used in Example 1 was used. In the microstructure of the mold used, the convex portion shape forming the groove portion has an inverted shape of the groove shape formed in the wire grid type polarizing element (R3) type, and the average width (a'). The average thickness (b'), the average length (c') of the portion ( D' ) that gradually becomes thinner toward the tip, and the period (d') of the arrangement are as shown in Table 1. be. The length of the portion ( D' ) that gradually becomes thinner toward the tip is gradually omitted from the shape of each convex portion (substantially square who or the bottom surface of the substantially quadrangular cone toward the apex). There are long and short lengths between the shapes that change into a conical shape), and in each case, the average length (c') in the tip direction of the portion ( D' ) that gradually becomes thinner toward the tip is the above. It was within 0.3 times the average length (b').
Using each of these molds, the fine groove structure was transferred to the sheet surface by the thermal nanoimprint method. FIG. 10 is a scanning electron microscope (SEM) photograph observed from diagonally above the front of the mold used in Example 8.

Then, by the squeezing method, the same silver nano ink used in Example 1 was filled in the groove portion, and after filling, the excess ink adhering to other than the inside of the groove portion was removed by wiping.
Next, the sheet filled with the ink in the groove was fired in an oven heated to 130 ° C. for 128 hours in Example 7 and 81 hours in Examples 8 and 9, and the silver fine particles contained in the ink were fired. A polarizing element test piece was prepared.
(2) Evaluation Results The degree of polarization, light transmittance, and light reflectance of the obtained polarizing element test piece were measured. These results are summarized in Table 1. Good effects were obtained on both the degree of polarization and the reflectance on the back surface side.

(Comparative Examples 1 and 2)
A fine groove structure is formed on the surface of the thermoplastic resin sheet by a thermal nanoimprint method using a mold, and then the groove is filled with an ink containing silver fine particles, and then silver contained in the ink is placed in a heated oven. A polarizing element test piece obtained by firing fine particles and having a wire grid type polarizing element (R1) type having a nearly linear cross section at the cutting edge in a one-dimensional lattice arrangement direction and perpendicular to the sheet surface. Made.

(1) Preparation of Polarizing Element Test Piece A sheet similar to that used in Example 1 was used. The microstructure of the mold used has an inverted shape of the groove shape formed in the wire grid type polarizing element (R1) type, and the convex portion shape forming the groove portion has an average width (a'). The average thickness (b'), the average length (c') of the portion ( D' ) that gradually becomes thinner toward the tip, and the period (d') of the arrangement are as shown in Table 1. be. Using each of these molds, the fine groove structure was transferred to the sheet by the thermal nanoimprint method. Further, FIG. 11 is a scanning electron microscope (SEM) photograph observed from diagonally above the front of the mold used in Comparative Example 2.

Then, the same silver nano ink used in Example 1 was filled in the groove by the squeezing method, and after filling, the excess ink adhering to the area other than the inside of the groove was removed by wiping.
Next, the sheet filled with the ink in the groove was fired in an oven heated to 130 ° C. for 12 hours in Comparative Example 1 and 81 hours in Comparative Example 2 to polarize the silver fine particles contained in the ink. A device test piece was prepared.
(2) Evaluation Results The degree of polarization, transmittance, and reflectance of the obtained polarizing element test piece were measured. These results are summarized in Table 1. From Comparative Example 1, when the ratio (b / a) of the average thickness (b) and the average width (a) of the metal reflector is 3.5, the degree of polarization decreases. When the ratio (c / a) of the average length (c) to the average width (a) of the gradually thinning portion in the tip direction is 1.0, the reflectance on the back surface side becomes slightly higher, reaching 0.89. It was found that the reflectance on the back surface side increased.

＊１：先端部平均長さ(c')と平均幅(a')との比(c'/a')を示す。
＊２：周期(d')と平均幅(a')との比(d'/a')を示す。
＊金属反射体の一次元格子状配列の周期(d')：１４０ｎｍ
＊実施例1～3：ワイヤグリッド型偏光素子（Ｒ１)タイプで、最先端部断面が凹凸形状
＊実施例4～6,比較例1,2：ワイヤグリッド型偏光素子（Ｒ１）タイプで、最先端部断面が略直線
＊実施例7～9：ワイヤグリッド型偏光素子（Ｒ３）タイプ

* 1: Shows the ratio (c'/ a') of the average length (c') of the tip and the average width (a').
* 2: Shows the ratio (d'/ a') between the period (d') and the average width (a').
* Period of one-dimensional lattice arrangement of metal reflector (d'): 140 nm
* Examples 1 to 3: Wire grid type polarizing element (R1) type with uneven cross section at the cutting edge * Examples 4 to 6, Comparative Examples 1 and 2: Wire grid type polarizing element (R1) type, most The cross section of the tip is substantially straight * Examples 7-9: Wire grid type polarizing element (R3) type

2. 2. Fabrication and Evaluation of Polarized Sunglasses Lenses are polarized by injection molding or cast polymerization in the following Examples 10 to 12 using the wire grid type polarizing element or the like manufactured in Example 7 above. Sunglass lenses were made and evaluated optically.

(Example 10)
Using the polarizing element test piece obtained in Example 7 above, after trimming, a spherical shape is formed by thermoforming, then placed in a mold and insert injection molded to perform insert injection molding, and a thermoformed resin layer is formed on the concave side. Was formed, and a polarized sunglasses lens was prototyped. Then, a hard coat film was formed on both sides of the obtained polarized sunglasses lens. The test pieces obtained in each of the above steps were optically evaluated.

(1) Hot Pressing of Wire Grid Type Polarizing Element After removing unnecessary parts of the polarizing element test piece obtained in Example 7, spherical hot pressing (bending) is performed by a known method. A spherical shape with a curvature of 8C (curvature radius = 66.81 mm) was produced. Specifically, a spherical shape used for injection molding is subjected to hot press molding (bending) at an anvil set temperature of 150 ° C. with the front side on which the metal reflector is formed as the upward side and the back side as the downward side. A polarizing element test piece was prepared. The obtained spherically shaped polarizing element test piece was optically measured using a spectrophotometer (model: U-4100) manufactured by Hitachi High-Tech Science Co., Ltd. The results were transparent with a degree of polarization of 97.4% and a light transmittance of 21.1%, and no deterioration in optical characteristics due to bending was observed.

(2) Preparation of Test Polarized Molded Body A polarized molded body was prepared as follows. The insert injection molding machine used is a device provided with a concave movable side mold having the same curvature capable of fixing the polarizing element test piece of the spherical shape body and a convex fixed side mold having an arbitrary curvature. Using this molding machine, the polarizing element test piece of the spherical shape obtained above was set in the concave movable side mold and fixed. In this case, the pattern surface side of the spherically shaped polarizing element test piece is in close contact with the movable side mold, and the back surface side is arranged so as to face the fixed side mold. The fixed side mold was tightened to the movable side mold. A transparent polycarbonate resin (manufactured by Mitsubishi Engineering Plastics Co., Ltd., trade name: Iupiron CLS3400) was used to form the thermoformed resin layer.

A test polarization molded product was injection-molded at a maximum temperature of 310 ° C. of the resin, and heat-bonded to the back surface side made of a polycarbonate sheet. Then, the test polarization molded product was taken out from the insert injection molding machine. The obtained test polarizing molded body is an 8C polarized sunglasses lens having a thickness of 2.2 mm, in which the pattern surface is arranged on the convex surface side and the thermoformed resin layer of transparent polycarbonate is integrally arranged on the concave surface side.
As a result of optical measurement of the produced polarized sunglasses lens, the degree of polarization was 97.3% and the light transmittance was 21.1%, and no deterioration in optical characteristics due to insert injection molding was observed.

(3) Formation of Hard Court Film A silicon-based hard coat film having a thickness of 2 μm was formed on both sides of the polarizing element test piece (polarized sunglasses lens) obtained above by a known method. The obtained hard-coated polarized sunglasses lens was subjected to optical measurement using the above spectrophotometer (manufactured by Hitachi High-Tech Science Co., Ltd.). As a result, the degree of polarization was 96.6% and the light transmittance was 25.2%, and no deterioration of the optical characteristics due to the hard coat was observed.
The prototype hard-coated polarized sunglasses lens had high polarization and high transmittance, and the reflectance on the concave side (eye side) was 3.7%, which was low reflection, and the appearance was also good.
Table 2 summarizes the degree of polarization and the light transmittance in each step. There was almost no decrease in the degree of polarization due to each step. There was almost no decrease in the light transmittance due to each process, but the light transmittance improved slightly after the formation of the hard coat. The cause of this is unknown, but it was also observed when a dye-based polarizing element was used. It is a phenomenon that can be seen.

(Example 11)
Using a polarizing element test piece made from a polyamide sheet, a spherical shape is formed by vacuum bending, and after trimming, it is placed in a mold and insert injection molding is performed to form a thermoformed resin layer on the concave side, and polarization is performed. I made a prototype of a sunglasses lens. Then, a hard coat film was formed on both sides of the obtained polarized sunglasses lens. Optical measurement was performed on the obtained test piece.

(1) Vacuum Pressing of Wire Grid Type Polarizing Element Wire grid type polarizing element produced in the same manner as in Example 7 above except that the polycarbonate sheet was changed to a transparent polyamide sheet (made by EMS, Grillamide TR90, thickness: 100 μm). The test piece was vacuum-pressed (bent) into a spherical shape by a known method to prepare a spherical shape having a curvature of 6C (curvature radius = 89.08 mm). Specifically, a spherical-shaped polarizing element used for injection molding is obtained by performing vacuum compressed air press molding (bending) with the pattern surface side of the polarizing element facing down and the back surface side facing up, and removing unnecessary parts. Made.

(2) Preparation of test polarization molded product The test polarization molded product was prepared as follows. The insert injection molding machine used is a device provided with a concave movable side mold having the same curvature capable of fixing the polarizing element of the spherical shape body and a convex fixed side mold having an arbitrary curvature. Using this device, the polarizing element of the obtained spherical shape was set in the concave movable side mold and fixed. In this case, the pattern surface side of the polarizing element of the spherical shape is in close contact with the movable side mold, and the back surface side is arranged so as to face the fixed side mold. The fixed side mold was tightened to the movable side mold. As the thermoformed resin layer, a transparent polyamide material (trade name: Grillamide TR90) manufactured by EMS was used. A test polarization molded product was injection-molded at a maximum temperature of 280 ° C. of the resin, and heat-bonded to the back surface of the polarizing element. Then, the test polarization molded product was taken out from the insert injection molding machine. The obtained test polarizing molded body was a 2.2 mm thick 6C polarized sunglasses lens in which the pattern surface was arranged on the convex surface side and the thermoformed resin layer was integrally arranged on the concave surface side of the polarizing element.

(3) Formation of Hard Coat Film A silicon-based hard coat film having a film thickness of 2 μm was formed on both sides of the test polarization molded product obtained above by a known method. Using the above spectrophotometer (manufactured by Hitachi High-Tech Science Co., Ltd.), the optical measurement of the produced polarized sunglasses lens with a hard coat was performed. The measurement results showed a degree of polarization of 96.2% and a light transmittance of 27.4%, and no deterioration in optical characteristics was observed. The produced polarized sunglasses lens with a hard coat had high polarization and high transmittance, and the reflectance on the back surface side (eye side) was 3.6%, which was low reflection, and the appearance was good.

(Example 12)
Using a polarizing element test piece made from a polyester sheet, a spherical shape is formed by vacuum bending, and then after press punching, it is placed in a mold and cast polymerization is performed to form a thermoformed resin layer on the concave side. Formed and prototyped a polarized sunglasses lens. Then, a hard coat film was formed on both sides of the obtained polarized sunglasses lens. Optical measurement was performed on the obtained test piece.
The molding (mold) and the preparation of the polymerizable liquid material were carried out as follows.

(I) Preparation of mold (mold) Glass lower mold (main body of first mold) (outer diameter 80 mm, used surface curvature 66.16 mm, center thickness 5.0 mm) and glass upper mold (main body of second mold) ) (Outer diameter 80 mm, used surface curvature 65.59 mm, center thickness 5.0 mm), first and second molds were prepared.

(Ii) Preparation of polymerizable liquid material 2,5-bicyclo [2,2,1] heptambis (methyl isocyanate) in 100 parts by mass, dibutyltin dichloride by 0.1 part by mass as a curing catalyst, and alkylphosphoric acid as an internal release agent. 0.3 parts by mass of ester (carbon atom number of alcohol: 8 to 12) salt, 0.2 parts by mass of ethyl caproate as an aroma-imparting agent, and 3- [5- (2-benzotriazoyl) as an ultraviolet absorber. ) -3-t-Butyl-4-hydroxyphenyl] 2.0 parts by mass of a monoester of propionic acid and polyethylene glycol was added, and the mixture was sufficiently stirred at a liquid temperature of 15 ° C. and a nitrogen gas atmosphere for 1 hour. Next, 50 parts by mass of pentaerythritol tetrakis (3-mercaptopropionate) and 50 parts by mass of 4,7-bis (mercaptomethyl) -3,6,9-trithia-1,11-undecandithiol were further added. , The liquid temperature was 15 ° C., and the mixture was sufficiently stirred for 1 hour in a nitrogen gas atmosphere.
Then, after degassing for 1 hour while stirring at a liquid temperature of 15 ° C. and 133 Pa using a vacuum pump, it is filtered with a filter having an opening of 1 μm, and the raw material liquid for a polythiourethane lens having a refractive index of 1.60 (polymerizable). Liquid material) was prepared.

(1) Vacuum press processing of wire grid type polarizing element Same as in Example 7 above except that the polycarbonate sheet was changed to a polyester sheet (manufactured by Toyobo Co., Ltd., polyester (trade name: Cosmoshine A4300), thickness: 250 μm). The wire grid type polarizing element test piece produced in the above process was vacuum-formed to a curvature of 66.00 mm. The obtained polarizing element was punched out by a circular press with an outer diameter of 79.0 mm to obtain a shaped polarizing sheet.

(2) Casting Polymerization After setting this excipient polarizing sheet between a set of two first and second molds described above, an adhesive tape was wound so that the center spacing was 3.0 mm to adjust the molding die. .. As the adhesive tape, a 38 μm thick PET film coated with a silicon-based adhesive was used. After injecting the polymerizable liquid material into the above-mentioned molding die, the polymer was heated under the following temperature conditions and polymerized and cured to form a polarized lens. The mold release was performed physically (mechanically) with a wedge-shaped tool.
(Hold at 30 ° C for 9 hours) → (heat up from 30 ° C to 60 ° C over 2 hours) →
(The temperature rises from 60 ° C to 120 ° C over 2 hours) → (Heating at 120 ° C for 2 hours) →
(Cooling from 120 ° C to 40 ° C over 4 hours)

(3) Formation of Hard Coat Film A silicon-based hard coat film having a film thickness of 2 μm was formed on both sides of the polarized lens obtained above by a known method. Using the above spectrophotometer (manufactured by Hitachi High-Tech Science Co., Ltd.), optical measurement of a polarized sunglasses lens with a hard coat was performed. The measurement results showed a degree of polarization of 96.2% and a light transmittance of 27.4%, and no deterioration in optical characteristics was observed. The produced polarized sunglasses lens with a hard coat had a high degree of polarization and a high transmittance, and the reflectance on the back surface side (eye side) was 3.6%, which was low reflection, and the appearance was good.

1, 2 Wire grid type polarizing element sheet (R1)
3 Wire grid type polarizing element sheet (R2)
4 Wire grid type polarizing element sheet (R3)
11 Sheet (A)
12 Front side of sheet (A) 13 Back side of sheet (A) 14, 16, 18 Metal reflector (B)
15, 17, 19 Part (D) that gradually becomes thinner toward the tip of the metal reflector (B)

Claims (3)

A polarized sunglasses lens in which a transparent resin layer for a lens is laminated on at least one of the back surface side and the front surface side of a wire grid type polarizing element sheet (W).
The polarizing element sheet (W) uses a transparent sheet (A) as a base material, and a metal reflector is formed on a large number of grooves (C) provided on the surface thereof in a one-dimensional lattice pattern in the same direction and at the same period. (B) is embedded
The average width (a) of the metal reflector (B) excluding the portion (D) that gradually becomes thinner toward the tip is 200 nm or less.
The ratio (b / a) of the average thickness (b) of the metal reflector (B) from the front surface side to the tip end in the back surface direction and the average width (a) is in the range of 4 to 25.
In addition, at least one of the cross-sectional shapes parallel to and perpendicular to the one-dimensional lattice arrangement direction near the tip of the metal reflector (B) in the thickness direction becomes linear or smooth curved and gradually narrows toward the tip. The ratio (c / a) of the average length (c) to the average width (a) of the portion (D) that gradually becomes thinner toward the tip is 1.2 or more. Characterized by that,
Polarized sunglasses lens. In the vicinity of the tip of the metal reflector (B) in the thickness direction, the shape of the portion (D) that gradually becomes thinner toward the tip is a cross-sectional shape perpendicular to the one-dimensional lattice arrangement direction, and the apex is in the tip direction. Positioned substantially inverted isosceles triangle shape (wire grid type polarizing element sheet (R1)),
In the cross-sectional shape in the one-dimensional grid arrangement direction and perpendicular to the sheet (A), the shape of the triangular wave is a continuous triangular wave shape, and the shape of the triangular wave is the shape of a continuous substantially inverted isosceles triangle (wire grid) in which the apex is located in the tip direction. Type polarizing element sheet (R2)), a substantially square cone in which the vertices of which the long sides intersect are located in the tip direction, or a substantially conical shape gradually changing from the bottom surface of the substantially square cone toward the apex. The shape is a shape (wire grid type polarizing element sheet (R3)) in which the shapes are continuous in the one-dimensional lattice arrangement direction.
The polarized sunglasses lens according to claim 1 or 2. The structure of the portion (D) in the vicinity of the tip portion of the metal reflector (B) in the thickness direction, which gradually becomes thinner toward the tip, is
In the case of the wire grid type polarizing element sheet (R1), the tip portion forms a continuous uneven shape in a one-dimensional lattice arrangement direction and in a cross-sectional shape perpendicular to the surface of the sheet (A). structure,
In the case of the wire grid type polarizing element sheet (R2), the height and wavelength of the triangular wave shape are irregularly continuous in the cross-sectional shape in the one-dimensional lattice arrangement direction and perpendicular to the sheet (A). structure,
Or, in the case of the wire grid type polarizing element sheet (R3), the length to the tip of the portion (D) that gradually becomes thinner toward the tip is approximately square from the bottom of each approximately square pyramid. A structure that has a regular or irregular difference in length between shapes that gradually change in a substantially conical shape toward the apex.
Moreover, in any of the above cases, the ratio (c / b) of the average length (c) of the portion (D) gradually becoming thinner toward the tip and the average thickness (b) in the tip direction is 0. It has a structure of 3 or less .
The polarized sunglasses lens according to any one of claims 1 to 5.