WO2018021445A1 - Multilayer sheet, lenticular sheet, curable composition for optical members, optical member, method for producing optical molded body, molded body, and method for producing cured product - Google Patents

Abstract

One embodiment of the present invention provides: a multilayer sheet, a lenticular sheet and applications thereof, each of which comprises a resin base and a cured product arranged on at least one surface of the resin base, said cured product containing a cured resin having a crosslinked structure and at least one skeleton selected from among a pyrrolidone skeleton and a caprolactam skeleton in a total content of 8% by mass or more relative to the total mass of the cured product.

Description

Laminated sheet, lenticular sheet, curable composition for optical member, optical member, method for producing optical molded body, molded body, and method for producing cured product

The present disclosure relates to a laminated sheet, a lenticular sheet, a curable composition for an optical member, a method for manufacturing an optical molded body, an optical member, a molded body, and a method for manufacturing a cured product.

Conventionally, a curable composition contains a polymerizable resin and an initiator, is cured by causing a polymerization reaction by heat or light, and is widely used in various applications. Moreover, the laminated sheet which laminated | stacked the hardened | cured material obtained by hardening | curing a curable composition is utilized widely, such as an optical member, a gas barrier film, a protective film, an optical filter, an antireflection film.
Furthermore, the cured product obtained by curing the curable composition is used for various members such as an antireflection film, a transparent pixel, a transparent insulating film, and a planarization film.
In recent years, there are a wide variety of optical members, and the optical structure of the optical member is not limited to a flat surface shape, for example, a brightness enhancement lens for a backlight for liquid crystal, a diffusion lens, and a Fresnel used for a screen of a video projection television. A lens, a microlens, etc. are mentioned. In such a device, a desired geometrical optical performance is obtained mainly by forming a fine structure with a resin material.

As an optical structure, a lenticular sheet using a lenticular lens in which convex lenses having a semicylindrical surface are arranged in parallel is known as a medium for displaying different images depending on viewing angles.
In a lenticular sheet, generally, an image sequence group (lenticular image) in which a plurality of interlaced images are combined is arranged on the back side of the lenticular lens (the surface opposite to the semi-cylindrical surface of the convex lens). When the row group is observed through a lenticular lens, one or more images in the image row group can be displayed depending on the viewing angle.

Therefore, it is expected to be used in various commercial applications including optical materials and optical screens. However, the applications proposed heretofore are mostly used in a two-dimensional form such as a sheet or a film, and are not often applied to a three-dimensional form formed into a three-dimensional shape.

As a technique attempted to be applied to a three-dimensional form, for example, an invention relating to an optical screen sheet obtained by molding a resin material for an optical screen has been proposed (see, for example, JP-A-2005-206742). However, in the invention described in Japanese Patent Application Laid-Open No. 2005-206742, a thermoplastic resin is used for the lens portion to be molded. For example, when three-dimensionalization is performed by vacuum molding or the like, It may be difficult to keep the shape stable with heat, and the structure of the lenticular sheet may not be maintained after molding.
On the other hand, as an example of optical applications, a technique using a curable composition containing a macromer having a (meth) acryloyl group, an acrylate, a polymerization initiator and the like in the production of an optical waveguide having excellent shape accuracy and the like is disclosed. (For example, refer to JP 2008-116971 A). Further, as an example of applying a curable composition in film applications, there is a disclosure relating to a technique for imparting hard coat properties by a composition containing polyfunctional acrylates, silica particles, high molecular weight monomers, etc. No. 287308).

However, if a cured product or a laminated sheet having the cured product is produced using a conventionally proposed resin composition having a curing property, and further molded into a three-dimensional structure by vacuum forming or the like, the cured product is obtained. Insufficient adhesion to the base material, the cured product may not only peel from the base material during three-dimensional molding, but the cured product itself may crack during molding by vacuum molding or the like, and the cured product itself may be damaged. .

The present disclosure has been made in view of the above circumstances.
The problem to be solved by one embodiment of the present invention is that the adhesion with the substrate is good, the film has heat resistance, and is stretchable when molded (preferably at high temperature). It is to provide a laminated sheet and a lenticular sheet.
The problem to be solved by other embodiments of the present invention is that excellent adhesion to a substrate is obtained, heat resistance is obtained after curing, and molding (preferably at high temperature) is performed. An object of the present invention is to provide a curable composition for an optical member that is excellent in stretchability when it is shaped.
Problems to be solved by other embodiments of the present invention include an optical member having good adhesion to a substrate, heat resistance, and stretchability, and a method for producing an optical molded body And providing a molded body.
The problem to be solved by another embodiment of the present invention is to provide a method for producing a cured product having good adhesion to a substrate, heat resistance, and stretchability. .

Specific means for achieving the object includes the following aspects.
<1> A resin base material and a cured product disposed on at least one surface of the resin base material, the cured resin having a crosslinked structure, and a total content of 8% by mass or more based on the total mass of the cured product, And a cured product having at least one skeleton selected from a pyrrolidone skeleton and a caprolactam skeleton.
<2> The laminated sheet according to <1>, wherein the total content of the pyrrolidone skeleton and the caprolactam skeleton is 15% by mass to 60% by mass with respect to the total mass of the cured product.
<3> Furthermore, it is a laminated sheet as described in <1> or <2> which has an image on the opposite side to the side which has a hardened | cured material of a resin base material.
<4> The laminated sheet according to any one of <1> to <3>, wherein the cured product is an optical member.
<5> The laminated sheet according to <4>, wherein the optical member is a cylindrical lens and is a lenticular sheet.
<6> A (meth) acrylic resin having a (meth) acryloyl group at the terminal, a polyfunctional (meth) acrylic monomer containing 2 or more and 4 or less (meth) acryloyl groups, and content relative to the total mass of the composition Containing at least one vinyl compound selected from vinyl pyrrolidone and vinyl caprolactam, the amount of which exceeds 10% by mass, and a radical photopolymerization initiator,
It is a curable composition for optical members used for preparation of the optical member for laminated sheets.
<7> The curable composition for optical members according to <6>, further comprising a monofunctional (meth) acrylic monomer.
<8> The content of the (meth) acrylic resin is 5 parts by mass or more and 40 parts by mass or less with respect to the total content of 100 parts by mass, and the content of the polyfunctional (meth) acrylic monomer is 1 part by mass or more. 75 parts by mass or less, a vinyl compound content of 15 parts by mass or more and 50 parts by mass or less, and a radical photopolymerization initiator content of 0.1 parts by mass or more and 5 parts by mass or less, <6 > Or <7>. The curable composition for optical members according to <7>.
<9> The curing for optical member according to any one of <6> to <8>, wherein the vinyl compound is vinylpyrrolidone and the content of the (meth) acrylic resin is 20 parts by mass or more and 40 parts by mass. Composition.

<10> The curable composition for optical members according to any one of <6> to <9> is molded and cured by irradiation with active energy rays, and the optical member is provided on the resin substrate. It is a manufacturing method of the optical molded body which has the process of producing a laminated sheet, and the process of obtaining an optical molded body by solid-molding (preferably thermoforming or vacuum forming) the produced laminated sheet.
<11> A molded body which is a thermoformed product or a vacuum formed product of the laminated sheet according to any one of <1> to <5>.
<12> The molded product according to <11>, which is an optical molded product.
<13> A method for producing a cured product, comprising a step of preparing the curable composition for optical members according to any one of <6> to <9>, and a step of curing the curable composition for optical members. It is.
<14> A laminated sheet having a cured product of the curable composition for optical members according to any one of <6> to <9>.
<15> An optical member having a cured product of the curable composition for optical members according to any one of <6> to <9>.
<16> A lenticular sheet having a cured product of the curable composition for optical members according to any one of <6> to <9>.

According to one embodiment of the present invention, a laminate having good adhesion to a substrate, heat resistance, and stretchability when molded (shaped) (preferably at a high temperature). Sheets and lenticular sheets are provided.
According to another embodiment of the present invention, excellent adhesion to a substrate is obtained, heat resistance is obtained after curing, and (preferably under high temperature) is molded (shaped) A curable composition for an optical member having excellent stretchability is provided.
According to another embodiment of the present invention, an optical member having good adhesion to a substrate, heat resistance, and stretchability, and an optical molded body manufacturing method and molded body are provided. Provided.
According to another embodiment of the present invention, there is provided a method for producing a cured product that has good adhesion to a substrate, has heat resistance, and has stretchability.

FIG. 1 is a schematic view showing an example of a display body provided with a lenticular sheet.

Hereinafter, a laminated sheet, a lenticular sheet, a curable composition for optical members, an optical member, a molded body, a method for manufacturing an optical molded body, and a method for manufacturing a cured product according to an embodiment of the present invention will be described in detail.

In the present specification, a numerical range expressed using “to” means a range including numerical values described before and after “to” as a lower limit value and an upper limit value. In a numerical range described in stages in the present disclosure, an upper limit value or a lower limit value described in a numerical range may be replaced with an upper limit value or a lower limit value in another numerical range. Further, in the numerical ranges described in the present disclosure, the upper limit value or the lower limit value described in a certain numerical range may be replaced with the values shown in the examples.
In addition, the term “process” in this specification is not limited to an independent process, and even if it cannot be clearly distinguished from other processes, the term is used as long as the intended purpose of the process is achieved. included.

In this specification, “(meth) acryl” is a term used in a concept including both acryl and methacryl, and “(meth) acryloyl” is a term used as a concept including both acryloyl and methacryloyl. It is.

<Laminated sheet, lenticular sheet>
The laminated sheet of one embodiment of the present invention has a resin base material and a cured product (preferably an optical member (cylindrical lens in the case of a lenticular sheet)) disposed on at least one surface of the resin base material. Preferably, an image (hereinafter also referred to as a decorative image) is provided on the side opposite to the side having the optical member of the resin base material. The image may be provided on the surface of the resin base opposite to the side having the optical member, or the recording layer may have a recording layer on the side opposite to the side of the resin base having the optical member. It may be provided by a known recording method such as
The cured product is preferably an optical member.

The laminated sheet according to the present disclosure is suitable as a laminated sheet having a hard coat film, a three-dimensionally laminated sheet, a laminated sheet having a brightness enhancement film, a lenticular sheet, a prism sheet, a microlens sheet, a Fresnel lens sheet, a fly eye lens, and the like. Can be used.

The laminated sheet of one embodiment of the present invention is suitably used as a lenticular sheet in which a cylindrical lens as an optical member is disposed on at least one surface of a resin base material.
As shown in FIG. 1, for example, the lenticular sheet may be a lenticular decorative sheet having a configuration in which a recording layer is provided and a lenticular image is attached. The lenticular decorative sheet has a lenticular lens in which convex cylindrical lenses (optical members) having a semi-cylindrical surface are arranged on an image suitable for lenticular display, thereby displaying different images depending on the viewing angle. It is a medium (lenticular display body). FIG. 1 is a schematic diagram illustrating an example of a lenticular decorative sheet.

The lenticular decorative sheet is an example of an optical decorative sheet.
A lenticular decorative sheet 10 shown in FIG. 1 includes a lenticular lens 12 in which a plurality of convex lenses (cylindrical lenses) 12A having a semicylindrical surface are arranged in parallel, and a semicylindrical surface of a convex lens 12A of the lenticular lens 12. And a lenticular image 14 arranged on the opposite side (also referred to as the back side).
The x direction indicates the width direction of the lens, and the y direction indicates the longitudinal direction of the lens.

Conventionally, laminated sheets such as lenticular materials are often used in the form of sheets or films, and there are few attempts to use them in a three-dimensional shape. However, in conventional laminated sheets, for example, as disclosed in Japanese Patent Application Laid-Open No. 2005-206742, a resin component used for a lens portion is generally a thermoplastic resin, and is deformed by heat when it is molded into a three-dimensional shape. And heat resistance that can maintain the shape tends to be insufficient. On the other hand, a technique using a thermosetting resin as a resin component has been proposed as disclosed in JP-A-2008-116971 and JP-A-2001-287308. However, thermosetting resins generally have a crosslinked structure. When it is deformed, the stretchability tends to be poor. For this reason, thermal deformation when exposed to a high temperature during molding is less likely to occur, but there is a concern that cracks or the like are likely to occur when extended during molding.
Therefore, in the optical member according to one embodiment of the present invention, a crosslinked structure is introduced using a thermosetting resin to prevent thermal deformation, and at least one of the pyrrolidone skeleton and the caprolactam skeleton is in a specific quantitative range. The composition is included. Thereby, it is possible to have both heat resistance and stretchability that can withstand heat and external force applied during forming such as vacuum forming while controlling the crosslinking density. Moreover, since a vinyl compound contributes to the improvement of the affinity with respect to a resin base material, the improvement effect of the adhesiveness with respect to the resin base material of an optical member is also acquired.

(Resin base material)
The resin base material in one embodiment of the present invention is a base material as a support material, and any resin can be selected according to the purpose and the like. As the resin substrate, a sheet-like or film-like substrate can be suitably used.

In one embodiment of the present invention, examples of the resin base material include sheets or films of acrylic resin, polyester resin, and the like.

The thickness of the resin substrate is not particularly limited and is preferably in the range of 50 μm to 300 μm, and more preferably in the range of 50 μm to 200 μm from the viewpoint of uniform molding (shaping) at high temperatures.

Commercially available products may be used as the resin substrate. For example, an acrylic resin film manufactured by Mitsubishi Rayon Co., Ltd. (Acryprene HBS010P, thickness: 125 μm), a polyethylene terephthalate resin film manufactured by Toray Industries, Inc. (Lumirror S10, thickness: 100 μm), polycarbonate resin film (Iupilon H-3000, thickness 125 μm) manufactured by Teijin Chemicals Ltd. and the like can be used.

(Cured product)
The cured product in the laminated sheet includes at least a cured resin having a crosslinked structure and at least one skeleton selected from a pyrrolidone skeleton and a caprolactam skeleton, and the total content of the pyrrolidone skeleton and the caprolactam skeleton is an optical member (lenticular sheet). In this case, the range is 8% by mass or more with respect to the total mass of the cylindrical lens). Moreover, the optical member may further contain other components as necessary.

The cured product includes optical members such as cylindrical lenses, prisms, hemispherical microlenses, and Fresnel lenses as convex lenses. As the cured product, an optical member is preferable, and a lenticular lens in which a plurality of convex lenses (cylindrical lenses) are arranged in parallel is particularly suitable as the optical member.

It can be confirmed from the infrared absorption spectrum (IR) that the pyrrolidone skeleton or the caprolactam skeleton is contained.

-Cured resin-
The cured product in the laminated sheet includes a cured resin having a crosslinked structure.
As will be described later, the curable resin includes a crosslinked structure formed by polymerization reaction of a polyfunctional (meth) acrylic monomer, and the polyfunctional (meth) acrylic monomer can remain in the resin. Since the polyfunctional (meth) acrylic monomer that undergoes the polymerization reaction under heating, it exhibits thermosetting properties.
The cured resin is imparted with a heat resistance effect by including a crosslinked structure.

The presence or absence of the crosslinked structure of the cured resin in the cured product can be confirmed by the following method.
When a cured product (for example, a lenticular lens) is scraped off from a laminated sheet, the cured product removed is added to tetrahydrofuran and dissolved, and when the cured product is not dissolved but remains as a filtered product, it is judged to have a crosslinked structure. To do.

As will be described later, the cured resin contained in the cured product is a (meth) acrylic resin having a (meth) acryloyl group at the terminal, a bifunctional to tetrafunctional (meth) acrylic monomer, a vinyl compound, and a photo radical. This is a resin cured by forming a crosslinked structure by a polymerization reaction of (meth) acryloyl groups using a curable composition containing a polymerization initiator. The vinyl compound is incorporated in the cured resin.
Specifically, radicals generated from the photo radical polymerization initiator when irradiated with active energy rays act on the (meth) acryloyl group of the (meth) acrylic resin and (meth) acrylic monomer, and (meth) acryloyl The groups are cured by a chain polymerization reaction.

For details of (meth) acrylic resin having a (meth) acryloyl group at the terminal, a (meth) acrylic monomer having 2 to 4 functionalities, a vinyl compound, and a radical photopolymerization initiator, which is a raw material of the cured resin It will be described later.

The content of the cured resin in the cured product is preferably 70% by mass or more and 100% by mass or less with respect to the total mass of the cured product such as an optical member (a cylindrical lens in the case of a lenticular sheet).
The cured resin contains a (meth) acrylic resin, a monomer component containing a polyfunctional (meth) acrylic monomer, and a vinyl compound.

-Pyrrolidone skeleton, caprolactam skeleton-
The cured product contains at least one skeleton selected from a pyrrolidone skeleton and a caprolactam skeleton as a structure derived from at least one vinyl compound selected from vinyl pyrrolidone and vinyl caprolactam.
The pyrrolidone skeleton and the caprolactam skeleton derived from the vinyl compound contribute to the improvement of the adhesion to the resin base described above, and improve the stretchability of the cured product (preferably an optical member) at the time of molding. Thereby, hardened | cured material (preferably optical member) is hard to peel from a resin base material, and generation | occurrence | production of the crack (crack) etc. which are easy to occur at the time of shaping | molding is suppressed.

The total content of the pyrrolidone skeleton and caprolactam skeleton with respect to the total mass of the cured product (preferably an optical member (cylindrical lens in the case of a lenticular sheet)) is in the range of 8 mass% or more. When the total content of the pyrrolidone skeleton and the caprolactam skeleton is in the above range, the adhesion to the resin base material is further improved, and the stretchability at the time of molding of the optical member which is a cured product is effectively improved.
The total content of the pyrrolidone skeleton and the caprolactam skeleton is preferably 15% by mass or more, more preferably 20% by mass or more, and further preferably 30% by mass or more. Moreover, although there is no restriction | limiting in particular about the upper limit of content of a vinyl compound, 60 mass% or less is preferable and 50 mass% or less is more preferable. When the content of the vinyl compound is 60% by mass or less, the heat resistance is further improved, the shape retainability of the cured product (preferably the optical member) can be kept good, and the lens shape remains the desired shape. Easy to hold.

The contents of the pyrrolidone skeleton and caprolactam skeleton can be determined from an infrared absorption spectrum (IR).

Examples of vinyl compounds that give a pyrrolidone skeleton and a caprolactam skeleton include N-vinyl-2-pyrrolidone and the like as an example of vinyl pyrrolidone, and N-vinyl-ε-caprolactam and the like as an example of vinyl caprolactam. Among the vinyl compounds, vinylpyrrolidone is preferable in that the stretchability at a high temperature at the time of molding is more excellent.

-Other ingredients-
In addition to the above components, the cured product may contain other components such as an organic solvent and inorganic particles as necessary. Details of the organic solvent, inorganic particles and the like will be described later.

As an example of the laminated sheet, a lenticular sheet is suitable.
The lenticular sheet has a lenticular lens layer in which a plurality of convex lenses (cylindrical lenses) having a semi-cylindrical surface are arranged in parallel, and the width per cylindrical lens is not particularly limited. What is necessary is just to select a pitch width. The width per cylindrical lens is usually often expressed by LPI (Line Per Inch) representing the number of lenses per inch (2.54 cm). For example, 100 LPI indicates that 100 cylindrical lenses (100 rows) per inch are arranged in parallel, and the pitch of the lenses is 254 μm. The larger the value of the number of lines per inch (number of lenses arranged), the smaller the lens pitch, and the higher the definition.
A low-definition lenticular sheet (for example, 60 LPI) is suitable for use in a poster or the like that displays a pattern whose observation position is relatively far. For the purpose of reading small text information such as a business card, it is preferable that the lenses constituting the lenticular lens layer are arranged in 100 rows or more per 2.54 cm (1 inch). On the other hand, from the viewpoint of the resolution of the lenticular image, the number of convex lenses constituting the lenticular lens layer is more preferably 200 rows (2.5 LPI) or less per 2.54 cm.

(image)
An optically displayed image (a lenticular image displayed in the case of a lenticular sheet) is provided on the side opposite to the side having a cured product such as an optical member of a resin base (cylindrical lens in the case of a lenticular sheet). The formed aspect is preferable. The lenticular image may be directly formed on the surface of the resin base material of the lenticular sheet. Further, the lenticular image may be an aspect in which a recording layer for recording the lenticular image is provided and the lenticular image is formed on the recording layer.
The surface of the resin substrate on which the lenticular image is formed may be subjected to surface treatment (for example, corona discharge treatment) from the viewpoint of increasing the adhesive force between the resin substrate and the recording layer.
The lenticular image may be formed, for example, by applying a colored liquid (for example, ink) for forming a lenticular image to a resin base material. The application of the coloring liquid (formation of a lenticular image) can be performed by, for example, a printing method such as offset printing, a coating method, an ink jet method, or the like.
The coloring liquid preferably contains a solid component and a solvent for forming a lenticular image. The lenticular image preferably contains a resin, and at least a part of the resin is preferably crosslinked with a crosslinking agent. Therefore, the aspect containing resin and a crosslinking agent as a solid component contained in a coloring liquid is preferable.
The resin is preferably at least one resin selected from polyester, acrylic resin, and urethane resin, and is particularly advantageous when a parallax image is formed by offset printing.

In FIG. 1, a lenticular image 14 includes display image sequences 14A and 14B for separately displaying two display images, and an interpolated image sequence 14C inserted between adjacent display image sequences 14A and 14B. And an image sequence group including
Specifically, the display image rows 14A and 14B extracted from each display image in a stripe shape are arranged adjacent to each other at the corresponding convex lens 12A, and the adjacent display image rows 14A and 14A are arranged. A color (interpolation color) between one color and the other color of the adjacent display image rows 14A and 14B at a position where the colors of the adjacent display image rows 14A and 14B are different from each other during 14B. The interpolated image sequence 14c is inserted.

<Curable composition for optical members>
The curable composition for optical members according to one embodiment of the present invention (hereinafter also simply referred to as “curable composition”) is suitably used for producing a cured product (for example, an optical member such as a cylindrical lens) in a laminated sheet. A composition having photocurability. It is suitably used for producing the laminated sheet of the present disclosure described above.

The curable composition for an optical member according to the present disclosure includes a (meth) acrylic resin having a (meth) acryloyl group at a terminal and a polyfunctional (meth) acrylic monomer containing two or more and four (meth) acryloyl groups. A body (hereinafter also referred to as “bifunctional to tetrafunctional (meth) acrylic monomer”), at least one vinyl compound selected from vinylpyrrolidone and vinylcaprolactam, and a radical photopolymerization initiator. And content of a vinyl compound shall be the range which exceeds 10 mass% with respect to the total mass of the curable composition for optical members.
The curable composition for optical members of the present disclosure may further contain other components such as an organic solvent and inorganic particles as necessary.

The curable composition for an optical member of the present disclosure contains a bifunctional to tetrafunctional (meth) acrylic monomer and a radical photopolymerization initiator, thereby forming a crosslinked structure and contributing to heat resistance. However, by containing a (meth) acrylic resin having a (meth) acryloyl group at the terminal and a specific amount of a specific vinyl compound, it is extended during molding (shaping). Occurrence of cracks or the like that tend to occur is suppressed, and adhesion to the resin base material is improved. That is, the curable composition for an optical member of the present disclosure is excellent in stretchability at the time of molding and excellent in adhesion to a resin substrate while maintaining excellent heat resistance by photocuring.

-(Meth) acrylic resin-
The curable composition for optical members contains at least one (meth) acrylic resin having a (meth) acryloyl group at the terminal. Since the (meth) acrylic resin has a (meth) acryloyl group at the end of the molecular chain, it is used in combination with the later-described (meth) acrylic monomer to control the crosslink density in the entire composition and to obtain a cured product. It is suitable for coexistence of heat resistance at the time of forming and stretchability at the time of molding.

As the (meth) acrylic resin, the main chain structure is not particularly limited as long as it is a polymer having a (meth) acryloyl group at the terminal. For example, polymethyl methacrylate (PMMA), polystyrene, polystyrene / methacrylate (MS resin), polystyrene -At the end of the main chain structure such as acrylonitrile (AS resin), polypropylene, polyethylene, polyethylene terephthalate, glycol-modified polyethylene terephthalate, polyvinyl chloride (PVC), thermoplastic elastomers, copolymers thereof, cycloolefin polymers ( Mention may be made of polymers having at least one (meth) acryloyl group. Among these, from the viewpoint of heat resistance, polymethyl methacrylate having a (meth) acryloyl group at the terminal and polystyrene having a (meth) acryloyl group at the terminal are preferable.

As the (meth) acrylic resin, a commercially available product may be used. As an example of a commercially available product, a macromonomer series manufactured by Toagosei Co., Ltd. (Example: Macromonomer AA-6 (polymethyl methacrylate having a methacryloyl group) , Macromonomer AS-6 or AS-6S (polystyrene having a methacryloyl group), macromonomer AN-6S (polystyrene / acrylonitrile having a methacryloyl group), macromonomer AB-6 (polybutyl methacrylate having a methacryloyl group), or the like is used. be able to.

The number average molecular weight of the (meth) acrylic resin is preferably in the range of 1000 or more and 10,000 or less, more preferably in the range of 3000 or more and 10,000 or less, and more preferably in the range of 5000 or more and 10,000 from the viewpoint of the balance of the composition viscosity that contributes to imparting stretchability. The following ranges are more preferable.

The number average molecular weight is a value measured by gel permeation chromatography (GPC).
Specifically, GPC uses HLC (registered trademark) -8220GPC (manufactured by Tosoh Corporation) as a measuring device, and 3 columns of TSKgel, Super Multipore HZ-H (manufactured by Tosoh Corporation, 4.6 mm ID × 15 cm) as a column. This is carried out using THF (tetrahydrofuran) as an eluent. As the conditions, the sample concentration is 0.45 mass%, the flow rate is 0.35 ml / min, the sample injection amount is 10 μl, the measurement temperature is 40 ° C., and the suggestive refractometer (RI) detector is used. In addition, the calibration curve is “Standard sample TSK standard, polystyrene” manufactured by Tosoh Corporation: “F-40”, “F-20”, “F-4”, “F-1”, “A-5000”, “ It is prepared from 8 samples of “A-2500”, “A-1000” and “n-propylbenzene”.

The glass transition temperature (Tg) of the (meth) acrylic resin is preferably 50 ° C. or higher. When Tg is 50 ° C. or higher, the heat resistance is excellent. Tg is preferably 80 ° C. or higher from the same viewpoint. Further, from the viewpoint of adhesion to the resin substrate and stretchability at the time of molding, Tg is preferably less than 250 ° C, and more preferably 200 ° C or less.

Tg is a peak that appears in the temperature range of 20 ° C. to 250 ° C. by preparing a sample containing (meth) acrylic resin by differential scanning calorimetry (DSC), cooling the sample to 20 ° C. with liquid nitrogen, It is requested from.

The (meth) acrylic resin having a (meth) acryloyl group at the terminal may be used alone or in combination of two or more.
As content in the curable composition for optical members of the (meth) acrylic resin which has a (meth) acryloyl group at the terminal, it is 5 mass with respect to 100 mass parts of total content of the curable composition for optical members. Part to 60 parts by weight, preferably 5 parts to 40 parts by weight, more preferably 10 parts to 30 parts by weight, and further preferably 15 parts to 25 parts by weight.
When the content of the (meth) acrylic resin is within the above range, the heat resistance and the stretchability at the time of molding are excellent. In addition, the content of the (meth) acrylic resin contributes to an increase or decrease in the viscosity of the curable composition for optical members, and when the content of the (meth) acrylic resin is within the above range, an optical member (for example, a lenticular lens). It is easy to ensure the height seen from the surface of the resin substrate. Among these, when the content of the (meth) acrylic resin is 5% by mass or more, the stretchability at the time of molding becomes good, and the occurrence of cracks (cracks) after molding is further suppressed. Further, when the content of the (meth) acrylic resin is 40% by mass or less, the heat resistance is excellent and the shape retention is excellent.

-(Meth) acrylic monomer-
The curable composition for optical members is at least a polyfunctional (meth) acrylic monomer having 2 to 4 (meth) acryloyl groups (a bifunctional to tetrafunctional (meth) acrylic monomer). 1 type is contained and you may contain a monofunctional (meth) acryl monomer in addition to a polyfunctional (meth) acryl monomer.
Since it contains a monomer (monomer) having a plurality of (meth) acryloyl groups, the (meth) acryloyl group undergoes a polymerization reaction to form a crosslinked structure, which contributes to an improvement in heat resistance due to the formation of the crosslinked structure.

(Bifunctional to tetrafunctional (meth) acrylic monomer)
The curable composition for optical members contains a polyfunctional (meth) acrylic monomer having 2 to 4 (meth) acryloyl groups contained in one molecule as the (meth) acrylic monomer.
When the number of (meth) acryloyl groups in the molecule is only one, a crosslinked structure cannot be formed. Therefore, a crosslinked structure can be obtained by setting the number of (meth) acryloyl groups in the molecule to two or more. , Heat resistance is improved. In addition, when the number of (meth) acryloyl groups in the molecule is 4 or less, the uniformity of the crosslinking density is high and the crosslinking is not excessively locally. It also has excellent adhesion.
Among the (meth) acrylic monomers, a bifunctional or trifunctional (meth) acrylic monomer is preferable from the same viewpoint as described above.

The (meth) acrylic monomer is not particularly limited as long as it is a (meth) acrylic monomer having 2 to 4 (meth) acryloyl groups, and examples thereof include the following compounds.
Specific examples of bifunctional (meth) acrylic monomers having two acryloyl groups in the molecule include tricyclodecane dimethanol di (meth) acrylate, diethylene glycol monoethyl ether di (meth) acrylate, dimethylol dicyclopentane. Di (meth) acrylate, di (meth) acrylated isocyanurate, 1,3-butylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, ethylene oxide (hereinafter abbreviated as “EO”). ) Modified 1,6-hexanediol di (meth) acrylate, epichlorohydrin (hereinafter referred to as “ECH”) modified 1,6-hexanediol di (meth) acrylate, allyloxy polyethylene glycol di (meth) acrylate, 1, 9-nonanediol di (meth) acryl EO modified bisphenol A di (meth) acrylate, propylene oxide (hereinafter referred to as “PO”) modified bisphenol A di (meth) acrylate, modified bisphenol A di (meth) acrylate, EO modified bisphenol F di (meth) acrylate , ECH-modified hexahydrophthalic acid di (meth) acrylate, hydroxypivalic acid neopentyl glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, EO modified neopentyl glycol di (meth) acrylate, PO modified neopentyl glycol Di (meth) acrylate, stearic acid modified pentaerythritol di (meth) acrylate, ECH modified phthalic acid di (meth) acrylate, ECH modified propylene glycol di (meth) acrylate, Corn di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, dimethylol tricyclodecane di (meth) acrylate, neopentyl glycol modified trimethylolpropane di (meth) acrylate, tripropylene Examples include glycol di (meth) acrylate, EO-modified tripropylene glycol di (meth) acrylate, triglycerol di (meth) acrylate, and dipropylene glycol di (meth) acrylate. Examples of commercially available products are A-DCP (tricyclodecane methanol diacrylate) manufactured by Shin-Nakamura Chemical Co., Ltd., A-HD-N (1,9-nonanediol di (Meth) acrylate) and the like can be used.

Specific examples of trifunctional (meth) acrylic monomers having three acryloyl groups in the molecule include isocyanuric acid EO-modified triacrylate, ECH-modified glycerol tri (meth) acrylate, EO-modified glycerol tri (meth) acrylate, PO Modified glycerol tri (meth) acrylate, pentaerythritol tri (meth) acrylate, EO modified phosphate tri (meth) acrylate, trimethylolpropane tri (meth) acrylate, caprolactone modified trimethylolpropane tri (meth) acrylate, EO modified trimethylol Examples include propane tri (meth) acrylate, PO-modified trimethylolpropane tri (meth) acrylate, and the like. Examples of commercially available products include M-315 (isocyanuric acid EO-modified triacrylate) manufactured by Toagosei Co., Ltd., A-TMPT (trimethylolpropane tri (meth) acrylate) manufactured by Shin-Nakamura Chemical Co., Ltd. Can be used.

Specific examples of tetrafunctional (meth) acrylic monomers having four acryloyl groups in the molecule include pentaerythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, and ethoxylated pentaerythritol tetra (meth) acrylate. And diglycerin EO-modified tetra (meth) acrylate. Examples of commercially available products are A-TMMT pentaerythritol tetraacrylate manufactured by Shin-Nakamura Chemical Co., Ltd., AD-TMP (ditrimethylolpropane tetra (meth) acrylate) manufactured by Shin-Nakamura Chemical Co., Ltd., etc. Can do.

The bifunctional or tetrafunctional (meth) acrylic monomer may be used alone or in combination of two or more.
The content of the bifunctional to tetrafunctional (meth) acrylic monomer in the curable composition for optical members is 1 mass relative to 100 parts by mass of the total content of the curable composition for optical members. Part or more and 75 parts by mass or less are preferable, 10 parts by mass or more and 70 parts by mass or less are more preferable, and 20 parts by mass or more and 60 parts by mass or less are more preferable.
When the content of the bifunctional to tetrafunctional (meth) acrylic monomer is 1 part by mass or more, the heat resistance is excellent and the shape retention is excellent. In addition, when the content of the bifunctional to tetrafunctional (meth) acrylic monomer is 75 parts by mass or less, the stretchability at the time of molding is improved, and the occurrence of cracks after the molding is more likely. It can be suppressed.

(Monofunctional (meth) acrylic monomer)
The curable composition for optical members includes a monofunctional (meth) acrylic monomer as a (meth) acrylic monomer, in addition to the bifunctional to tetrafunctional (meth) acrylic monomer. You may contain.
When a monofunctional (meth) acrylic monomer is used in combination with a bifunctional to tetrafunctional (meth) acrylic monomer, the bifunctional to tetrafunctional (meth) acrylic monomer is used. It is possible to further improve characteristics, particularly stretchability and adhesion.

Specific examples of monofunctional (meth) acrylic monomers include adamantyl (meth) acrylate compounds such as 1-adamantyl (meth) acrylate, norbornyl (meth) acrylate compounds such as isobornyl (meth) acrylate, and dicyclopentanyl. Tricyclodecane (meth) acrylate compounds such as methacrylate, 2-ethyl-2-butylpropanediol (meth) acrylate, 2-ethylhexyl (meth) acrylate, 2-ethylhexyl carbitol (meth) acrylate, 2-hydroxybutyl (meth) ) Acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-methoxyethyl (meth) acrylate, 3-methoxybutyl (meth) acrylate, 4-hydroxy Chill (meth) acrylate, benzyl (meth) acrylate, 1- or 2-naphthyl (meth) acrylate, butanediol mono (meth) acrylate, butoxyethyl (meth) acrylate, butyl (meth) acrylate, cetyl (meth) acrylate, Ethylene oxide (EO) modified cresol (meth) acrylate, dipropylene glycol (meth) acrylate, ethoxylated phenyl (meth) acrylate, ethyl (meth) acrylate, isoamyl (meth) acrylate, isobutyl (meth) acrylate, isooctyl (meth) acrylate Cyclohexyl (meth) acrylate, dicyclohentanyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, isomyristyl (meth) acrylate, Uril (meth) acrylate, methoxydipropylene glycol (meth) acrylate, methoxytripropylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methyl (meth) acrylate, neopentyl glycol Benzoate (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, nonylphenoxypolypropylene glycol (meth) acrylate, octyl (meth) acrylate, paracumylphenoxyethylene glycol (meth) acrylate, ECH-modified phenoxy (meth) acrylate, phenoxyethyl (Meth) acrylate, phenoxydiethylene glycol (meth) acrylate, Phenoxyhexaethylene glycol (meth) acrylate, phenoxytetraethylene glycol (meth) acrylate, stearyl (meth) acrylate, EO-modified succinic acid (meth) acrylate, tert-butyl (meth) acrylate, tribromophenyl (meth) acrylate, EO Examples thereof include modified tribromophenyl (meth) acrylate and tridodecyl (meth) acrylate. Examples of commercially available products are FA-513AS (dicyclopentanyl acrylate) manufactured by Hitachi Chemical Co., Ltd., Light acrylate IB-XA (isoboronyl acrylate) manufactured by Kyoeisha Chemical Co., Ltd. Can do.

The content of the monofunctional (meth) acrylic monomer in the curable composition for an optical member may be in a range that does not impair the effects in the embodiment of the present invention. Although it depends on the content of the acrylic monomer, for example, it can be in the range of 1 part by mass to 50 parts by mass with respect to 100 parts by mass of the total content of the curable composition for optical members.

-Vinyl compounds-
The curable composition for optical members contains at least one vinyl compound selected from vinyl pyrrolidone and vinyl caprolactam. A vinyl compound contributes to the improvement of adhesiveness with the above-mentioned resin base material, and improves the stretchability at the time of shaping | molding of the optical member which is a hardened | cured material.
Thereby, the cylindrical lens which is a cured product is hardly peeled off from the resin base material, and the occurrence of cracks or the like that are likely to occur during molding is suppressed.

Content with respect to the total mass of the curable composition for optical members of a vinyl compound shall be the range exceeding 10 mass%. When the content of the vinyl compound is within the above range, the adhesiveness to the resin base material is further improved, and the stretchability when the cured product (optical member) is obtained is improved.
As content of a vinyl compound, 15 to 60 mass% is preferable. The lower limit of the content of the vinyl compound is more preferably 20% by mass or more, further preferably 25% by mass or more, and further preferably 30% by mass or more. Moreover, about the upper limit of content of a vinyl compound, 40 mass% or less is more preferable. When the content of the vinyl compound is 60% by mass or less, the heat resistance is further improved, the shape retaining property of the optical member that is a cured product can be maintained well, and the lens shape is maintained in a desired shape. Cheap.

Among vinyl compounds, examples of vinyl pyrrolidone include N-vinyl-2-pyrrolidone. Examples of vinyl caprolactam include N-vinyl-ε-caprolactam.

Among the vinyl compounds, vinyl pyrrolidone is preferable because it is more excellent in stretchability at a high temperature during molding.

-Photo radical polymerization initiator-
The curable composition for optical members contains at least one kind of radical photopolymerization initiator. A photoradical polymerization initiator is a compound that generates a radical as an active species that initiates a polymerization reaction of a (meth) acryloyl group when exposed to light.

The radical photopolymerization initiator is not particularly limited in structure. For example, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide, 2,2-dimethoxy-1,2-diphenylethane-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, 1- [4- (2-hydroxyethoxy) -phenyl ] -2-Hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1- {4- [4- (2-hydroxy-2-methyl-propionyl) -benzyl] phenyl} -2-methyl -Propan-1-one, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropa 1-one and the like.

Commercially available products that are commercially available may be used as the photoradical polymerization initiator. As specific examples of commercially available products, BASF's Irgacure series (eg: IRGACURE TPO, IRGACURE 819, IRGACURE 651, IRGACURE 184, IRGACURE 1173) IRGACURE 2959, IRGACURE 127, IRGACURE 907, etc.).

The radical photopolymerization initiator may be used alone or in combination of two or more.
The content of the radical photopolymerization initiator with respect to the total mass of the curable composition for optical members is preferably in the range of 0.1 parts by mass or more and 5 parts by mass or less.
When the content of the radical photopolymerization initiator is 0.1 parts by mass or more, the polymerization reaction proceeds favorably, and a cured product having better heat resistance is obtained. Moreover, since the effect corresponding to content cannot be anticipated even if it contains a radical photopolymerization initiator in the range which content contains more than 5 mass parts, it is preferable that it is 5 mass parts or less.
The content of the photo radical polymerization initiator is more preferably 0.5 parts by mass or more and 3 parts by mass or less, and further preferably 1 part by mass or more and 3 parts by mass or less.

In the curable composition for optical members of one embodiment of the present invention, the total content of the curable composition for optical members of 100 mass from the viewpoint of the effects (heat resistance, stretchability and adhesion) in the embodiments of the present invention. The content of the (meth) acrylic resin is 5 parts by mass or more and 40 parts by mass or less, the content of the polyfunctional (meth) acrylic monomer is 1 part by mass or more and 75 parts by mass or less, and vinyl. It is preferable to prepare a composition having a compound content of 15 parts by mass or more and 50 parts by mass or less and a radical photopolymerization initiator content of 0.1 parts by mass or more and 5 parts by mass or less.

Moreover, in the curable composition for optical members of one embodiment of the present invention, from the viewpoint of the effect (heat resistance, stretchability and adhesion) in the embodiment of the present invention, in particular, vinylpyrrolidone is contained as a vinyl compound, And it is more preferable to prepare to the composition which content of the (meth) acrylic resin which has a (meth) acryloyl group at the terminal was 20 mass parts or more and 40 mass parts.

-Other ingredients-
In addition to the above components, the cured product may contain other components such as an organic solvent and inorganic particles as necessary.
Examples of the organic solvent include toluene and methyl ethyl ketone. In the embodiment of the present invention, since the (meth) acrylic monomer is included, the (meth) acrylic monomer also serves as a solvent and does not need to contain an organic solvent separately.
Examples of the inorganic particles include so-called filler particles such as silicon dioxide (silica). Examples of inorganic particles include commercially available organosilica sol MEK-ST series (eg, MEK-ST-40, MEK-ST-L, etc.) manufactured by Nissan Chemical Industries.

<Hardened product and production method thereof>
The cured product according to the present disclosure is at least one selected from a (meth) acrylic resin having a (meth) acryloyl group at a terminal, a (meth) acrylic monomer having 2 to 4 functionalities, vinylpyrrolidone, and vinylcaprolactam. A curable composition containing a vinyl compound and a radical photopolymerization initiator, wherein the content of the vinyl compound exceeds 10% by mass relative to the total mass of the curable composition for optical members. Is a cured product (cured product of the curable composition according to the present disclosure).
The cured product according to the present disclosure can be suitably used as an optical member, and a cylindrical lens, a prism, a hemispherical microlens, a Fresnel lens, or the like can be more suitably used as a convex lens, and a plurality of convex lenses It can be particularly suitably used as a lenticular lens in which (cylindrical lenses) are arranged in parallel.
Moreover, the optical member which concerns on this indication has the hardened | cured material which concerns on this indication.
The manufacturing method of the hardened | cured material which concerns on this indication does not have a restriction | limiting in particular, It is preferable that it is a manufacturing method including the process of preparing the curable composition which concerns on this indication, and the process of hardening | curing the said curable composition. Further, for example, the curing of the curable composition according to the present disclosure may be photocuring (curing by irradiation with active energy rays) or heat curing, but is preferably photocuring.

<Manufacturing method of molded body and optical molded body>
The molded body of the present disclosure is a three-dimensional molded body that is a thermoformed product or a vacuum molded product produced by molding the laminated sheet of the present disclosure described above (preferably by a technique such as thermoforming or vacuum forming). . The molded body of the present disclosure may be a molded product having a three-dimensional shape, and includes an optical molded body.
The molded body of the present disclosure is not particularly limited to a molding method as long as it is a method using the above-described laminated sheet.
The molded body of the present disclosure is preferably a step of forming a curable composition for an optical member and curing it by irradiation with an active energy ray to produce a laminated sheet having an optical member on a resin substrate (hereinafter referred to as “a laminated sheet”). , Also referred to as “laminated sheet manufacturing step”), a step of obtaining an optical molded body by three-dimensionally molding (preferably vacuum forming) the prepared laminated sheet (hereinafter also referred to as “three-dimensional molding step”), (The manufacturing method of the optical molded object of one Embodiment of this invention). In this case, an optical molded body is manufactured as the molded body.

Since the laminated sheet according to one embodiment of the present invention described above is used for molding that is exposed to a relatively high temperature, it is difficult to cause shape deformation by melting with heat during molding, and is extended during molding. Occurrence of cracks or the like that are likely to occur during the process is also suppressed.

-Laminated sheet manufacturing process-
In the laminated sheet production process in the present disclosure, the curable composition for an optical member is molded and cured by irradiation with active energy rays to produce a laminated sheet having an optical member on a resin substrate.
The details of the curable composition for optical members are as described above, and the preferred embodiments are also the same.

Since the curable composition for optical members contains a radical photopolymerization initiator, radicals are generated when irradiated with active energy rays, and a (meth) acrylic resin and a bifunctional to tetrafunctional (meth) acrylic. It hardens | cures when the polymerization reaction of the (meth) acryloyl group in a monomer advances. Thereby, the optical member which is a hardened | cured material of the curable composition for optical members is shape | molded.
Before molding the optical member curable composition, the resin base material is brought into contact with the optical member curable composition in advance before curing the optical member curable composition. Also good. By curing in a state where the resin substrate and the curable composition for optical members are in contact with each other, an improvement in adhesion due to curing shrinkage can be expected, and in addition to the adhesion effect derived from the composition, adhesion to the resin substrate Is improved more effectively.
From the viewpoint of adhesion of the optical member to the resin base material, a laminated sheet having an optical member superior in adhesion can be obtained by curing the curable composition for an optical member in contact with the resin base material.

In this step, first, the curable composition for an optical member is three-dimensionally formed into the shape of the target optical member before curing. Molding is not particularly limited as long as the desired shape can be obtained, but molding using a mold such as a mold or a wooden mold is preferable from the viewpoint of molding efficiency and molding accuracy.
Specifically, for example, a mold processed into a desired lens shape is prepared, and the curable composition for an optical member is poured into the mold and dried as necessary, and then the curable composition for an optical member. The object may be cured. Thereby, the molded object shape | molded by the target shape is obtained stably.

Active energy rays include γ rays, β rays, electron beams, ultraviolet rays, visible rays, and the like.
As light sources for generating active energy rays, mercury lamps, metal halide lamps, UV fluorescent lamps, gas lasers, solid lasers, and the like are widely known. Further, a semiconductor ultraviolet light emitting device may be applied as a light source, and an LED (Light Emitting Diode) and an LD (Laser Diode) are also suitable in terms of small size, long life, high efficiency, and low cost.
As the light source, a metal halide lamp, an ultra high pressure mercury lamp, a high pressure mercury lamp, a medium pressure mercury lamp, a low pressure mercury lamp, an LED, or a blue-violet laser is preferable. Among them, an ultra-high pressure mercury lamp capable of irradiating light with a wavelength of 365 nm, 405 nm or 436 nm, a high-pressure mercury lamp capable of irradiating light with a wavelength of 365 nm, 405 nm or 436 nm, or light irradiation with a wavelength of 355 nm, 365 nm, 385 nm, 395 nm or 405 nm Are more preferable, and an LED capable of irradiating light with a wavelength of 355 nm, 365 nm, 385 nm, 395 nm, or 405 nm is most preferable.

The dose of the active energy ray may be appropriately selected depending on the composition and amount of the optical member for the curable composition, for example, be a 0.3 J / cm ² or more 5 J / cm ² or less.

The irradiation with the active energy ray can be performed by selecting a known device including a light source capable of irradiating the active energy ray. For example, an ultraviolet (UV) irradiation device such as EXECULE 3000 manufactured by HOYA CANDEO OPTRONICS may be used.

-Solid molding process-
In the three-dimensional forming step in the present disclosure, the laminated sheet produced in the laminated sheet producing step is three-dimensionally formed. In this step, it is sufficient that the laminated sheet can be formed, and the laminated sheet may be subjected to a forming process using a mold such as a mold.

Suitable examples of the three-dimensional molding include thermoforming and vacuum forming.
The method for vacuum forming is not particularly limited, but the effect of forming by the method for producing an optical molded body according to an embodiment of the present invention when three-dimensional molding is performed in a heated state under vacuum. Appears prominently.
The vacuum refers to a state in which the room is evacuated to a degree of vacuum of 100 Pa or less.
The temperature during three-dimensional molding is preferably a high temperature range of 60 ° C. or higher, more preferably a temperature range of 80 ° C. or higher, and even more preferably a temperature range of 100 ° C. or higher. In general, the upper limit of the temperature for three-dimensional molding is preferably 200 ° C.
The temperature at the time of three-dimensional molding refers to the temperature of the laminated sheet subjected to molding, and is measured by attaching a thermocouple to the surface of the laminated sheet.

The above-described vacuum forming can be performed by using a vacuum forming technique widely known in the forming field. For example, the vacuum forming may be performed using Formech 508FS manufactured by Nippon Shikki Kogyo Co., Ltd.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof. Unless otherwise specified, “part” is based on mass.
In the following examples, a case where a lenticular sheet is manufactured as an example of a laminated sheet and a lenticular lens in which cylindrical lenses are arranged in parallel is described as an example of an optical member.

Example 1
-Preparation of curable composition-
The components in the composition shown below were mixed to prepare a cured composition (cured composition for optical member) for producing a cylindrical lens as an optical member.
<Composition>
Polymethylmethacrylate (PMMA) 20 parts (AA-6, manufactured by Toagosei Co., Ltd .; methacrylic resin having a methacryloyl group at the end)
Tricyclodecane methanol diacrylate 48 parts (A-DCP, manufactured by Shin-Nakamura Chemical Co., Ltd .; bifunctional acrylic monomer having acryloyl group (bifunctional acrylate))
・ N-vinyl-2-pyrrolidone (manufactured by Wako Pure Chemical Industries, Ltd.) 30 parts ・ Irgacure TPO 2 parts (2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, manufactured by BASF; acyl Phosphine oxide photo radical polymerization initiator)

-Production of lenticular lens sheet-
As shown in FIG. 1, the shape of a lenticular lens in which a plurality of convex cylindrical lenses having a semi-cylindrical surface are arranged in parallel [height 60 μm, length 80 mm in the longitudinal direction y, one lens width (lens pitch ) 100 LPI (Line Per Inch)] was poured into a mold (width 100 mm × depth 100 mm), and 2 g of the curable composition was poured into the mold, and an acrylic resin film (Acryprene HBS010P, thickness: 125 μm, Mitsubishi Rayon Co., Ltd. resin base material) was placed and fixed. Next, the curable composition poured into the mold was irradiated with ultraviolet rays (UV) through an acrylic resin film (UV irradiation). UV irradiation was performed using an ultraviolet (UV) irradiation apparatus (EXECURE 3000, manufactured by HOYA CANDEO OPTRONICS) until curing was performed under the condition of a UV irradiation amount of 1.0 J / cm ² . After UV irradiation, the curable composition irradiated with UV was demolded to obtain a lenticular lens sheet.
Since lenticular lenses use N-vinyl-2-pyrrolidone, the lenticular lenses contain a pyrrolidone skeleton. Further, since the lenticular lens is a cured product that is cured by polymerizing a bifunctional acrylate, the lenticular lens has a cross-linked structure.

-Fabrication of single film-
The above curable composition is sandwiched between two glass plates that have been subjected to a hydrophobic treatment, irradiated with UV under the same conditions as described above, and peeled off from the glass plate to form a cured resin film (single film) having a thickness of 50 μm. Produced.

(Examples 2 to 8, Comparative Examples 1 and 4)
In Example 1, a curable composition was prepared in the same manner as in Example 1 except that the composition of the curable composition for producing a cylindrical lens or the resin base material was changed as shown in Table 1 below. Further, a lenticular lens sheet and a single film were produced.
Since lenticular lenses use N-vinyl-2-pyrrolidone or N-vinyl-ε-caprolactam, the lenticular lenses contain a pyrrolidone skeleton or a caprolactam skeleton. Since the lenticular lens is a cured product that is cured by polymerizing a bifunctional acrylate or a hexafunctional acrylate, the lenticular lens has a crosslinked structure.

Example 9
Using the same cured composition as in Example 1, a film laminate was produced by the following method.
-Production of film laminate-
The above curable composition is sandwiched between a hydrophobized glass plate and an acrylic resin film having a thickness of 50 m, which is a resin base material, irradiated with UV under the same conditions as described above, and peeled off from the glass plate after irradiation. did. Thus, the film laminated body (laminated sheet) which consists of a 50-micrometer-thick resin cured film and an acrylic resin film was produced.

The details of each component in Table 1 are as follows.
PET: Polyethylene terephthalate (Lumirror, manufactured by Toray Industries, Inc .; base material)
AS-6: manufactured by Toagosei Co., Ltd., polystyrene having a methacryloyl group at the terminal ((meth) acrylic resin having a (meth) acryloyl group at the terminal)
AN-6S: manufactured by Toagosei Co., Ltd., solid content: 51% by mass, polystyrene acrylonitrile having a methacryloyl group at the terminal ((meth) acrylic resin having a (meth) acryloyl group at the terminal)
-Kayrad DPHA: manufactured by Nippon Kayaku Co., Ltd., a hexafunctional acrylic monomer having an acryloyl group (hexafunctional acrylate)
・ N-vinyl-ε-caprolactam (manufactured by Tokyo Chemical Industry Co., Ltd.)
MEK-ST: Organosilica sol (manufactured by Nissan Chemical Industries)

(Comparative Examples 2-3)
-Production of lenticular lens sheet-
Place the pellets of polymethyl methacrylate (PMMA, Sumipex LG, manufactured by Sumitomo Chemical Co., Ltd.) or polystyrene (PS, HF-77, manufactured by PS Japan Co., Ltd.) on the processed surface of the same mold as the mold used in the examples. And heated at 200 ° C. for 5 minutes. After heating, a polycarbonate (PC) film (Iupilon H-3000, thickness: 125 μm, manufactured by Mitsubishi Chemical Corp .; base material) was placed, and thermocompression bonded for 5 minutes under a pressure of 20 MPa using a melt press. Then, it removed from the melt press and obtained the lenticular lens sheet for a comparison.
PMMA and PS are the same even when powder is used instead of pellets.

-Fabrication of single film-
A pellet of polymethyl methacrylate (PMMA) or a pellet of polystyrene (PS) is sandwiched between two Kapton (registered trademark) films (200H, manufactured by Toray DuPont), and the temperature is 200 ° C. and the pressure is 20 MPa using a melt press. Under the conditions described above, thermocompression bonding was performed for 5 minutes. Then, it took out from the melt press and peeled off the film to produce a resin film (single film) having a thickness of 50 μm.
PMMA and PS are the same even when powder is used instead of pellets.

(Evaluation)
The following evaluation was performed with respect to the lenticular lens sheet, the resin cured film (single film), and the film laminate produced as described above. The evaluation results are shown in Table 1 below.

-1. Heat resistance (shape retention)-
The shape of the lenticular lens sheet or film laminate after being left in an environment at a temperature of 80 ° C. for 1000 hours was observed and evaluated according to the following evaluation criteria.
<Evaluation criteria>
A: The change rate of the lens height or the height (thickness) of the cured product of the film laminate is less than 5%.
B: The change rate of the lens height or the height (thickness) of the cured product of the film laminate is 5% or more and less than 10%.
C: The rate of change of the lens height or the height (thickness) of the cured product of the film laminate is 10% or more.

-2. High temperature stretchability
A sample piece is made by punching a cured resin film (single film) into a size of 50 mm length x 10 mm width, and a tensile test using TENSILON RTC-1225A (manufactured by A & D) under the following conditions. And the elongation at break was measured. The measurement was performed three times, and the average value of the three measurements was taken as the breaking elongation. Using the measured value of elongation at break as an index for evaluating the extensibility at a high temperature during molding, the extensibility was evaluated based on the following evaluation criteria. The standard of elongation is 30 mm of the distance between chucks. Of the evaluation criteria, the range of AA to B is a practically acceptable range.
<Condition>
・ Distance between chucks: 30mm
-Sample piece temperature: 100 ° C
・ Tensile speed: 1mm / sec <Evaluation criteria>
AA: The elongation at break is 20% or more.
A: The elongation at break is 15% or more and less than 20%.
B: The elongation at break is 10% or more and less than 15%.
C: The elongation at break is less than 10%.

-3. Substrate adhesion
11 parallel cuts reaching the resin substrate from the resin cured film, PMMA film or PS film surface by a method based on JIS K5600-5-6 (1999) on the lenticular lens sheet or film laminate. Then, the direction of 90 ° was changed, and another 11 parallel cuts were made to partition the resin cured film, PMMA film or PS film in a lattice shape. The interval between the cuts was 2 mm. A cellophane adhesive tape (CT-24, manufactured by Nichiban Co., Ltd.) is applied to the surface of each film partitioned in a grid, and then the cellophane adhesive tape is gripped and pulled in a direction perpendicular to the surface direction. The presence or absence of the peeled part was confirmed visually. Evaluation was performed according to the following evaluation criteria.
<Evaluation criteria>
A: There is no peeling part.
B: The ratio of the peeled portion to the entire surface is more than 0% and less than 15%.
C: The ratio of the peeled portion to the entire surface is 15% or more.

 

As shown in Table 1, a polyfunctional (meth) acrylic monomer is used, a crosslinked structure is formed to impart heat resistance, and a specific skeleton structure, that is, a pyrrolidone skeleton or a caprolactam skeleton is in a specific amount range. In the included examples, the stretchability at high temperature was excellent, and the adhesion to the resin substrate was also good. In particular, better results were obtained when vinylpyrrolidone (pyrrolidone skeleton) was included and the content of the (meth) acrylic resin was 20 to 40 parts by mass.
In contrast, Comparative Example 1 in which the content of the pyrrolidone skeleton derived from the vinyl compound N-vinyl-2-pyrrolidone was 10% by mass was inferior in adhesion to the resin substrate. Furthermore, in Comparative Example 4 which does not contain a vinyl compound (pyrrolidone skeleton and caprolactam skeleton), the shape having a desired lens height is remarkably inferior in adhesion and stretchability at high temperature, and the content of (meth) acrylic resin is small. Was not obtained.

The disclosures of Japanese Patent Application No. 2016-147489 filed on July 27, 2016 and Japanese Patent Application No. 2017-061854 filed on March 27, 2017 are incorporated herein by reference in their entirety.
All documents, patent applications, and technical standards mentioned in this specification are to the same extent as if each individual document, patent application, and technical standard were specifically and individually stated to be incorporated by reference, Incorporated herein by reference.

Claims (16)

1. A resin substrate;
   A cured product disposed on at least one surface of the resin base material, which is selected from a cured resin having a crosslinked structure, and a pyrrolidone skeleton and a caprolactam skeleton having a total content of 8% by mass or more based on the total mass of the cured product A cured product having at least one skeleton,
   A laminated sheet having
2. The laminated sheet according to claim 1, wherein the total content of the pyrrolidone skeleton and the caprolactam skeleton is 15% by mass or more and 60% by mass or less with respect to the total mass of the cured product.
3. Furthermore, the lamination sheet of Claim 1 or Claim 2 which has an image on the opposite side to the side which has the said hardened | cured material of the said resin base material.
4. The laminated sheet according to any one of claims 1 to 3, wherein the cured product is an optical member.
5. The laminated sheet according to claim 4, wherein the optical member is a cylindrical lens and is a lenticular sheet.
6. A (meth) acrylic resin having a (meth) acryloyl group at the end;
   A polyfunctional (meth) acrylic monomer containing 2 or more and 4 or less (meth) acryloyl groups;
   At least one vinyl compound selected from vinyl pyrrolidone and vinyl caprolactam, the content of which exceeds 10% by mass with respect to the total mass of the composition;
   A radical photopolymerization initiator;
   Containing
   A curable composition for an optical member, which is used for producing an optical member for a laminated sheet.
7. Furthermore, the curable composition for optical members according to claim 6, further comprising a monofunctional (meth) acrylic monomer.
8. For a total content of 100 parts by weight,
   The content of the (meth) acrylic resin is 5 parts by mass or more and 40 parts by mass or less,
   The content of the polyfunctional (meth) acrylic monomer is 1 part by mass or more and 75 parts by mass or less,
   The vinyl compound content is 15 parts by mass or more and 50 parts by mass or less, and
   The content of the radical photopolymerization initiator is 0.1 parts by mass or more and 5 parts by mass or less.
   The curable composition for optical members according to claim 6 or 7.
9. The curability for an optical member according to any one of claims 6 to 8, wherein the vinyl compound is vinyl pyrrolidone, and the content of the (meth) acrylic resin is 20 parts by mass or more and 40 parts by mass. Composition.
10. A laminated sheet having the optical member on a resin substrate, wherein the curable composition for an optical member according to any one of claims 6 to 9 is molded and cured by irradiation with an active energy ray. A manufacturing process;
    A process of obtaining an optical molded body by three-dimensionally molding the produced laminated sheet;
    The manufacturing method of the optical molded object which has this.
11. A molded body which is a thermoformed product or a vacuum formed product of the laminated sheet according to any one of claims 1 to 5.
12. The molded article according to claim 11, which is an optical molded article.
13. A method for producing a cured product, comprising a step of preparing the curable composition for an optical member according to any one of claims 6 to 9, and a step of curing the curable composition for an optical member.
14. A laminated sheet having a cured product of the curable composition for optical members according to any one of claims 6 to 9.
15. An optical member having a cured product of the curable composition for an optical member according to any one of claims 6 to 9.
16. A lenticular sheet comprising a cured product of the curable composition for optical members according to any one of claims 6 to 9.

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