JP2004347768A - Light shielding pattern forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a microlens sheet constituted by arraying convex lenses two-dimensionally and in a matrix state, where a high-density light shielding layer having no unevenness is formed. <P>SOLUTION: The light shielding pattern forming method includes a stage to form a lens 5 on one surface of a supporting body 1 through which ionizing radiation 6 can be transmitted and form an ionizing radiation curing type resin layer 2 having adhesiveness on an opposite surface; a stage to radiate the ionizing radiation 6 from the side of the lens 5 so as to cure a part 8 on which light is condensed by the lens 5 in the resin layer 2 and lose the adhesiveness but maintain the adhesiveness of a non light condensing part 7; and a stage to form a light shielding pattern by press-fitting and peeling a transfer sheet 10 where coloring layers 4 and 9 consisting of at least two layers are formed from the side of the resin layer 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a method of forming a light-shielding layer (light-shielding pattern) composed of a black photosensitive layer by utilizing the property that the adhesiveness changes upon exposure to light and the adhesion to a substrate (support) changes. The present invention relates to a microlens array sheet on which a light-shielding layer used for a rear projection screen used for a liquid crystal projector or the like is formed by a method.
[0002]
[Prior art]
Conventionally, as a rear projection screen used in a liquid crystal projector or the like, a convex cylindrical lens used in combination with a Fresnel lens sheet is mainly a lenticular sheet that is one-dimensionally arranged side by side, and a pattern forming a light shielding layer is: This is a stripe pattern (referred to as black stripe “BS”) corresponding to the non-light-collecting portion of the cylindrical lens.
[0003]
In order to view a high-definition image having a large number of pixels, the convex cylindrical lens pitch of the lenticular sheet is also made fine, and accordingly, the light-shielding pattern (BS) is also made fine. In order to realize a high-definition light-shielding pattern, it is necessary to realize a transfer layer capable of transferring a high-resolution fine pattern.
In other words, when forming a light-shielding layer on a flat surface opposite to the lens portion of the lenticular sheet, a photosensitive layer (a known material that loses its tackiness when exposed to light) is formed on the entire flat surface. Exposure from the lens side denatures the photosensitive layer in the light-collecting area, and attaches ink or toner to the non-light-collecting area and transfers the transfer layer. This is preferably implemented in order to form a light-shielding layer at an accurate position by a so-called self-alignment method based on the light-gathering characteristics of the lens itself. In particular, the pattern for forming the light-shielding layer by the above-described transfer forming method is excellent in the sharpness of the light-shielding layer and the pattern contour (for example, see Patent Document 1).
[0004]
[Patent Document 1]
JP-A-9-120102
On the other hand, when a microlens sheet having a configuration in which unit convex lenses are two-dimensionally arranged in a matrix is employed instead of a lenticular sheet as a back-illuminated type screen used in a liquid crystal projector or the like, the light-shielding pattern is spot-shaped. Is a pattern excluding the light condensing part of the unit convex lens.
[0006]
In order to improve the contrast of a displayed image to be viewed, a light-shielding layer (black matrix “BM”) is provided on a flat portion opposite to the lens array portion (observer side), at a portion corresponding to a non-light-collecting portion of each unit lens. Is preferred and is customarily practiced.
[0007]
Even in a microlens sheet in which minute unit lenses are two-dimensionally arranged in a matrix at a fine pitch, it is preferable to form a pattern with a high light blocking ratio in order to view an image with high contrast. Although it is necessary to form a pattern excluding the condensing portion of the unit convex lens which is a minute spot, compared to the case of forming a stripe-shaped light-shielding layer using a lenticular sheet, the resolution is higher and the resolution is higher. There has been a demand for a technique capable of forming a light-shielding layer composed of a transfer layer that can be transferred in a pattern.
[0008]
As described above, a light-shielding pattern such as a black stripe (BS) or a black matrix (BM) is formed on a lens using a lenticular lens. However, in the case of a fine pitch of BS or a matrix such as BM, especially in the transfer method, the cut property of the ink layer of the transfer foil is poor and the direction in the peeling direction is poor. This causes a problem that a fine pattern cannot be formed due to tailing and jagged phenomenon at the time of peeling. In consideration of such foil stripping properties, conventionally, as a method of forming a single layer of the ink layer, the adhesive force between the adhesive photosensitive resin on the substrate to be transferred and the ink layer is strengthened and the transfer is performed. A method has been used in which the adhesion of the ink layer to the support of the sheet is strengthened and the cohesive force of the ink layer is reduced, but peeling unevenness called zipping occurs due to high peeling strength in continuous peeling operation. was there. That is, when the transfer / non-transfer is faithfully performed on the surface of the stripe pattern in which the adhesive portions / non-adhesive portions defined by exposure on the photosensitive resin layer alternately, tailing and jagging at the time of peeling are avoided. Above, cohesive peeling (a technique of breaking and transferring inside the ink layer) was effective. However, in this method, since it is difficult to control the breaking position, there is a problem that thickness unevenness occurs in the transfer layer and black density tends to vary. Further, according to the interfacial peeling method of peeling off at the interface between the ink layer and the transfer sheet substrate, the black density can be secured, but the peeling strength is required as compared with the cohesive peeling, and there is a problem of causing a problem of zipping. Was.
[0009]
[Problems to be solved by the invention]
The present invention has been made in view of the above technical background, and provides a microlens sheet in which convex lenses having a high-density light-shielding layer without unevenness are two-dimensionally arranged in a matrix. That is the task.
[0010]
[Means for Solving the Invention]
In order to solve the above-mentioned problem, the invention according to claim 1 includes forming a lens on one surface of a support that is capable of transmitting ionizing radiation, and forming an ionizing radiation-curable resin layer having adhesiveness on the other surface. Forming and irradiating ionizing radiation from the side of the lens, curing the portion focused by the lens of the ionizing radiation-curable resin layer to lose the adhesiveness, the adhesiveness of the non-light-collecting portion is Maintaining, and forming a light-shielding pattern by pressing and peeling a transfer sheet on which at least two colored layers are formed from the side of the ionizing radiation-curable resin layer. And
[0011]
The invention according to claim 2 is that the colored layers composed of at least two layers are in close contact with each other, and the colored layers closest to the base material of the transfer sheet are not separated at the interface, and are laminated so that the next layer and the subsequent layers do not undergo cohesive failure. It is characterized by having.
[0012]
In the invention according to claim 3, the pigment content of the coloring layer closest to the base material of the transfer sheet is 60 parts by weight to 90 parts by weight, and the pigment content of the subsequent layers is 10 parts by weight to 59 parts by weight. It is characterized by having.
[0013]
The invention according to claim 4 is characterized in that the thickness of the colored layer closest to the base material of the transfer sheet is 0.1 μm to 3 μm, and the thickness of the next layer and subsequent layers is 1 μm to 10 μm. .
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment as a preferred example of the present invention will be described with reference to the drawings. FIG. 1 is a diagram illustrating an example of a method for forming a light-shielding layer (light-shielding pattern) according to the present invention. FIG. 1 (a) shows a microlens array (or lenticular sheet) 5 formed on one surface of a substrate (support) 1. FIG. 4B is a diagram showing a process of forming an ionizing radiation-curable resin layer 2 on the opposite surface. FIG. 4B shows ionizing radiation (for example, UV = UV or electron beam) applied to the ionizing radiation-curable resin layer 2 from the microlens array 5 side. = EB etc.) to form a photosensitive pattern 8 and a non-photosensitive pattern 7 on the ionizing radiation-curable resin layer 2, and FIG. 2C shows the transfer sheet 10 according to the present invention shown in FIG. It is a figure which shows the process of peeling.
In FIGS. 1C and 2, reference numerals 3, 4, and 9 indicate a substrate (or a support), a first colored layer (an agglomerated release layer), and a second colored layer (an interface release layer), respectively. ing.
FIG. 3 is a view showing the shapes of the photosensitive pattern 8 and the non-photosensitive pattern 7 as viewed from the microlens array 5 side.
[0015]
A microlens array is formed on one surface of the substrate 1 to form a light shielding layer. In manufacturing this microlens array, after forming a molding stamper, molding by a 2P method (Photo-Polymer method) is adopted.
The stamper is a reverse type of a microlens sheet (that is, a surface shape in which a unit lens portion is a concave portion), and the concave portion is mechanically carved on the surface of a metal layer. Alternatively, a method such as chemical corrosion or a method such as engraving the concave portion by laser processing is used.
In any method, it is needless to say that the shape of the curved surface of the unit lens needs to be accurately processed, and it is selected according to the definition.
[0016]
The following can be used as the microlens array sheet 5 used in the present invention.
<Micro lens array sheet>
FIG. 4 is a diagram showing an example of the microlens array sheet of the present invention, and (a) is a cross-sectional view of the microlens array sheet. (B) is a plan view of the microlens array sheet in which the shape of the region (unit lens region) where the irregularities forming the unit lens are formed is rectangular, and the unit lens region has a grid pattern. is there. (C) is a plan view in the case where the unit lens region has a triangular shape and the unit lens region has a delta arrangement in the microlens array sheet. (D) is a plan view of the microlens array sheet in which the unit lens region has a hexagonal shape and the unit lens region has a honeycomb arrangement in the microlens array sheet.
[0017]
At least one surface of the transparent resin film substrate 1 has a unit lens 5 two-dimensionally arranged in a matrix, and has a microlens array portion made of a reaction cured product of an ultraviolet or ionizing radiation curable resin. It is a lens array sheet. The microlens array section includes a unit lens having an aspherical or spherical curved surface, and the arrangement pitch of the unit lenses is 100 μm or less.
[0018]
The arrangement of the unit lenses forms a matrix arrangement of a grid pattern, a delta arrangement, or a honeycomb arrangement.
The microlens array portion may contain a filler having a refractive index similar to that of the reaction cured product, a release agent, an antistatic agent, and the like.
[0019]
<Formation of light-shielding pattern>
As a method of forming the light-shielding layer of the present invention, a transparent adhesive ionizing radiation-curable resin 2 is applied or laminated on a substrate 1 (FIG. 1A). By exposing from the surface of the lens 5, a pattern is formed in which the condensing portion 8 of the ionizing radiation-curable resin 2 is cured and the non-condensing portion 7 is uncured. ". The light-shielding layer as shown in FIG. 1 (c) is formed by overlapping and pressing and peeling the ink layer surface of the transfer sheet of FIG. 2 of the present invention on this portion.
[0020]
Specific examples of the film used for the microlens lens sheet of the present invention include plastic films such as polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon, polyimide, polyvinylidene chloride, and ionomer. No. In addition, it is desirable that one or both surfaces be subjected to a corona treatment or an easy adhesion treatment in order to adjust the adhesion of the photosensitive resin to the surface of the base material.
[0021]
The material to be applied or laminated on the microlens array sheet is an ultraviolet-sensitive resin material having a transparent adhesive property, but is not particularly limited. For example,
(1) Photopolymerizable compound of monomer, oligomer and / or prepolymer (2) Thermoplastic resin having no photopolymerizability if necessary (3) Photopolymerization initiator activated by actinic ray Contains thermal polymerization inhibitor.
[0022]
Examples of the ink layer binder resin colored black in the present invention include polyvinyl chloride, poly (meth) acrylic acid, poly (meth) acrylate, polyvinyl ether, polyvinyl acetal, urethane resin, epoxy resin, and poamide resin. , Diacryl phthalate, ethylene vinyl acetate, styrene resin, epoxy acrylic resin, ethylene vinyl acetate resin and the like.
[0023]
Examples of the black colorant include inorganic pigments, organic pigments, and carbon, but carbon is preferred from the viewpoint of dispersibility and black density.
[0024]
Examples of the substrate 3 of the transfer sheet 10 include plastic films such as polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon, polyimide, polyvinylidene chloride, and ionomer.
[0025]
In the invention according to claims 1 and 2, the transfer sheet preferably has two or more colored layers. In the case of a single layer, when the cohesive force of the ink layer is improved in consideration of the foil breaking property, interfacial peeling occurs at the time of pressure-bonding peeling, and uneven zipping occurs. Also, if the cohesive force of the ink layer is reduced, cohesive failure occurs during pressure peeling, which makes it difficult to control the position of the breakage and lowers the black density. By controlling the black density in the second and subsequent layers, a good light-shielding pattern can be formed.
[0026]
The invention according to claim 3 is a method for adjusting the cohesive force of the ink. In the case of a composition that coagulates and separates, the pigment weight part in the layer is preferably 60 to 90 parts by weight, and in the case of interfacial release, 10 to 59 parts by weight. Parts are preferred. Exceeding this range results in different peeling states, which makes it impossible to form a good light-shielding layer.
[0027]
The invention described in claim 4 is an essential thickness for maintaining the peeled state of claim 2, and 0.1 μm to 3 μm is good for cohesive failure and 1 μm to 10 μm is good for interfacial peeling. . Exceeding this range results in different peeling states, making it impossible to form a good light-shielding layer.
[0028]
【The invention's effect】
According to the present invention, it is possible to provide a method for forming a light shielding layer having a high resolution and a fine pattern.
According to the method of forming a light-shielding layer of the present invention, a microlens array sheet in which unit convex lenses having a light-shielding layer formed at a predetermined position with high accuracy at a high light-shielding rate and a high transmission density are two-dimensionally arranged in a matrix is provided. By combining this with a Fresnel lens sheet, a horizontal projection angle and a vertical viewing angle are both wide, and a high-resolution rear projection screen can be provided.
[Brief description of the drawings]
FIGS. 1A and 1B are diagrams illustrating a method for forming a light-shielding property of the present invention, in which FIG. 1A shows a step of forming a microlens array on one side and forming an ultraviolet-sensitive resin layer on the other side, and FIG. ) Shows a step of irradiating the UV-sensitive resin layer with UV from the microlens array side to form a photosensitive pattern and a non-photosensitive pattern on the UV-sensitive resin layer, and FIG. It is a figure which shows the process of overlapping pressure bonding peeling.
FIG. 2 is a schematic sectional view of a transfer sheet according to the present invention.
FIG. 3 is a schematic exploded perspective view showing the shapes of a photosensitive pattern 8 and a non-photosensitive pattern 7 as viewed from the microlens array 5 side.
FIGS. 4A and 4B are explanatory views showing the configuration of a microlens array sheet used in the present invention, wherein FIG. 4A is a cross-sectional view of the microlens array sheet, and FIG. FIG. 3C is a plan view of a microlens array sheet having a delta lens arrangement, and FIG. 4D is a plan view of a microlens array sheet having a honeycomb arrangement.
[Explanation of symbols]
1 Microlens substrate (support)
2 ionizing radiation-curable resin layer 3 transfer sheet substrate 4 first colored layer (aggregated release layer)
Reference Signs List 5 Microphone lens array 6 Ionizing radiation 7 Non-photosensitive pattern 8 Photosensitive pattern 9 Second colored layer (interface release layer)
10 Transfer sheet

Claims (4)

Forming a lens on one surface of the support that is capable of transmitting ionizing radiation, and forming an ionizing radiation-curable resin layer having tackiness on the other surface,
Irradiating ionizing radiation from the side of the lens, curing the portion focused by the lens of the ionizing radiation-curable resin layer to lose adhesiveness, maintaining the adhesiveness of the non-light-collecting portion,
Forming a light-shielding pattern by pressure-bonding and peeling off a transfer sheet on which at least two colored layers are formed from the side of the ionizing radiation-curable resin layer. Method. The at least two colored layers are in close contact with each other, and the colored layer closest to the base material of the transfer sheet is laminated so as not to be peeled off at the interface, and that the subsequent layers are not cohesively broken. 2. The method for forming a light-shielding pattern according to 1. The pigment content of the coloring layer closest to the base material of the transfer sheet is 60 parts by weight to 90 parts by weight, and the pigment content of the subsequent layers is 10 parts by weight to 59 parts by weight. 3. The method for forming a light-shielding pattern according to 1 or 2. The film thickness of the colored layer closest to the base material of the transfer sheet is 0.1 μm to 3 μm, and the film thickness of the subsequent layer is 1 μm to 10 μm. The method for forming a light-shielding pattern according to claim 1.

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