JP2003191249A - Manufacturing methods of transfer master, transfer film and diffuse reflection plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a diffuse reflection plate for reflection type LCD having excellent reflective characteristics, and also to provide a manufacturing method of a transfer master, a transfer film and the diffuse reflection plate used for manufacturing the plate. <P>SOLUTION: The surface of a matrix for molding is so shaped that a large number of spherical-crown-shaped particles are arranged adjacently and closely and the surface thus shaped is a continuous curved surface. Using the transfer master formed in this way, a transfer base film having the shape transferred by pressing the transfer master on the transfer film, is obtained. Using the transfer base film as a temporary support, a thin film layer is formed on the surface of the temporary support onto which the transfer master is transferred, and the transfer film wherein the surface of the thin film layer not formed on the temporary support constitutes a surface adhering to a base being an object of transfer, is obtained. The diffuse reflection plate is manufactured by a process of pressing the transfer film on the base so that the thin film layer faces the base, a process of peeling the temporary support and a process of forming a reflective film on the surface onto which the thin film layer is transferred. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reflective liquid crystal display device that does not require a backlight and a diffuse reflection plate for a solar cell that requires high efficiency, and the diffusion reflection plate and the transfer used for manufacturing the same. The present invention relates to a prototype, a transfer film, and a method for manufacturing a diffuse reflection plate using the transfer film.

[0002]

2. Description of the Related Art Liquid crystal display (hereinafter abbreviated as LCD)
Taking advantage of its thinness, small size, and low power consumption, is currently used for display parts of watches, calculators, TVs, personal computers and the like. Furthermore, in recent years, color LCDs have been developed and OA / AV
It is beginning to be used in many applications such as navigation systems, viewfinders, personal computer monitors, etc., centering on equipment, and the market is expected to expand rapidly in the future. In particular, a reflective LCD that reflects light incident from the outside to display an image is attracting attention as a portable terminal device application because it does not require a backlight and thus consumes less power and can be made thinner and lighter. ing.

Conventionally, a twisted nematic system and a super twisted nematic system have been adopted for reflective LCDs, but in these systems, half of the incident light is not used for display due to the linear polarizer, and the display is dark. turn into. Therefore, we reduced the number of polarizers to one and combined it with a retardation film or a phase transition type guest.
Host-based display modes have been proposed.

In order to efficiently use external light in a reflective LCD to obtain a bright display, it is necessary to further increase the intensity of light scattered in a direction perpendicular to the display screen with respect to incident light from all angles. There is. Therefore, it is necessary to control the reflection film on the reflection plate so as to obtain appropriate reflection characteristics. For this reason, the reflector has a high reflectance metal,
For example, it has been attempted to use aluminum or silver, or to laminate a reflection enhancing film on a metal in order to improve the reflectance of the metal surface. Further, there is a so-called photolithography method (Japanese Patent Laid-Open No. 4-243226) in which a substrate is coated with a photosensitive resin, patterned using a photomask to form irregularities, and a metal thin film is formed to form a reflector. Proposed. In addition, a method of manufacturing a master block in which a concave portion is continuously formed by pressing an indenter having a spherical tip, and a method of manufacturing the reflector by transferring the master block to the reflector substrate have been proposed (Japanese Patent Laid-Open No. 11- No. 42649). In addition, there has been proposed a method of forming a film on a substrate by dispersing fine particles in a resin in order to control the diffusibility (Japanese Patent Laid-Open No. 7-1).
10476 publication).

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the method of Japanese Patent Publication No. 6, since there is a step of exposing and developing the substrate with a photomask in order to form a roughened surface, the steps are complicated, and it cannot be said that the cost is low and the productivity is high. Further, it is difficult to form a large area in a random pattern in the process of producing a photomask. Further, since the flat portion removed by the development increases the intensity of specular reflection, the reflection of the light source tends to increase. JP-A-5-23
In Japanese Patent No. 2465, after a pattern is formed, a resin film or the like is used.
A method of forming a second film to eliminate the flat portion has been proposed. Further, since the method disclosed in Japanese Patent Laid-Open No. 11-42649 does mechanical work, it is difficult to perform fine processing. The layer in contact with the liquid crystal layer is planarized by overcoating or the like, but it is difficult to form a roughened surface having a size of several microns or less, which is advantageous for planarization. Further, it is difficult to form a roughened surface on a large area at random. In both cases, the same roughened surface shape is continuously arranged and regularity occurs. As a result, moire occurs due to interference with the laminated color filter and the pattern of the ITO electrode. In addition, there is a problem that the light is dispersed and iridescent is seen, which deteriorates the display quality of the reflective LCD. On the other hand, Japanese Patent Laid-Open No. 11-38214 proposes a method of spraying particles into stripe-shaped grooves to randomly form recesses. Although the rainbow color does not occur in the method disclosed in JP-A-7-110476, it is difficult to uniformly disperse the fine particles, and in order to obtain a necessary range of reflection intensity, the fine particle concentration is reduced or the particle size is reduced. Even if you change
Since the gaps between the particles are generated, the reflection at the regular reflection angle becomes high at the flat portion, and the problem that the light source is reflected is seen. Japanese Unexamined Patent Publication No. 2000-267088 has proposed the formation of a roughened surface by plating, but in order to obtain a necessary reflection intensity, the reflection at the regular reflection angle becomes high, and the problem of strong reflection of the light source is found. Was given. As described above, according to the conventional method, (1) a large area is made uniform,
(2) Forming a random uneven shape without moiré,
Moreover, (3) it is difficult to reduce the specular reflection and eliminate the reflection of the light source. In the conventional method, a scattering antireflection layer may be formed on the surface to prevent it, but it cannot be said to be the best method because the reflectance is lowered. The present invention is a reflection type LC having good reflection characteristics.
It is intended to provide a diffusion reflection plate for D, a transfer pattern used for the production thereof, a transfer film, and a method for producing the diffusion reflection plate.

[0006]

In order to solve the above problems, the surface of the molding die has a shape in which a large number of spherical crown-shaped particles are arranged adjacent to each other without a gap, and the shape surface is a continuous curved surface. It was found that the problem can be solved by using a transcription prototype that is In addition, by forming granular projections on the surface of the molding die and then plating the surface with a leveling effect, the light is diffused to the required diffusion angle, and the specular reflection is low, and the image of the light source is not reflected. It is possible to manufacture a transfer pattern having a characteristic of being less crowded. The shape can be transferred to a transfer target film to form a transfer base film, and if necessary, a reflective film may be provided on the transfer base film to form a diffuse reflection plate. Further, the transfer base film produced by the above method is used as a temporary support to form a transfer film by laminating a thin film layer on the diffusion surface, and the substrate is pressed so that the surface of the thin film layer not laminated to the temporary support faces. By removing only the temporary support and forming a reflective film on the thin film layer, a diffuse reflector is obtained. In addition, since a random granular protrusion is formed in order to plate the molding die, moire does not occur, and by controlling the shape of the granular protrusion and the leveling plating conditions, a large number of spherical crown-shaped particles can be obtained. Is formed,
A surface is obtained in which there are no flat portions between the particles and the entire surface is formed by a large number of continuous spherical surfaces. As a result, since the reflection at the regular reflection angle can be reduced, the reflection of the light source is small, and a diffuse reflection plate having a uniform reflection intensity over a necessary range can be manufactured. Using the transfer base film,
When a shape is transferred by pressing so that the surface transferred to the thin film layer formed on the substrate faces, and a reflective film is formed on the thin film layer, a diffuse reflector having excellent reflection characteristics can be manufactured.
A step in which the transfer base film is used as a temporary support, a reflective film is provided on the transfer surface, and a thin film layer is further laminated to form a transfer film, and the film is pressed against a substrate so that the thin film layer faces the temporary support; By the process of peeling off, the diffuse reflection plate can be manufactured. According to the present manufacturing method, it is possible to obtain the diffuse reflection characteristic in which no moire is generated and the reflection of the light source is small. Further, the shape reproducibility is good, and a large-area diffuse reflection plate can be manufactured by a simple process.

That is, the present invention is [1] a transfer prototype in which the surface of the molding die is a shape in which a large number of spherical crown-shaped particles are arranged adjacent to each other without a gap, and the shape surface is a continuous curved surface. is there. [2] A method for producing a transfer master, which comprises forming a granular projection on the surface of a molding die and further forming a plating having a leveling effect on the surface. [3] A transfer master formed by a step of forming granular projections on the surface of the molding die and further performing plating having a leveling effect on the surface. Also, [4]
A transfer base film having a shape transferred by using the transfer master according to the above [1] or [3] and pressing the transfer master against a transfer target film. Also,
[5] Using the transfer base film described in [4] above as a temporary support, a thin film layer is formed on the surface of the temporary support on which the transfer pattern is transferred, and the surface of the thin film layer that is not formed on the temporary support is It is a transfer film that constitutes an adhesive surface to a transfer substrate. [6] The transfer film according to the above [5], wherein a reflective film is formed between the temporary support and the thin film layer. [7] A step of pressing the transfer film according to [5] above onto a substrate so that the thin film layer faces, a step of peeling off the temporary support, and a reflective film formed on the transferred surface of the thin film layer. It is a method of manufacturing a diffuse reflection plate, in which the diffusion reflection plate is manufactured by the step of. [8] A method for manufacturing a diffuse reflection plate, comprising a step of pressing the transfer film according to the above [6] onto a substrate so that the thin film layer faces, and a step of removing the temporary support, thereby producing a diffusion reflection plate. is there. [9] a step of pressing the transfer base film according to the above [4] against a thin film layer formed on a substrate so that the transferred surface faces, a step of peeling off the transfer base film, and a surface A method for manufacturing a diffuse reflection plate, including the step of forming a reflection film on the substrate. [10] A diffuse reflection plate obtained by the method for producing a diffuse reflection plate according to any of [7] to [9]. Also,
[11] A diffuse reflection plate in which a reflection film is provided on the surface of the transfer base film of the above [4] onto which the transfer pattern is transferred. [12] The above [10] or the above [11]
A diffuse reflection plate characterized by using the diffusion reflection plate described in 1 above in a reflective liquid crystal display.

[0008]

1 is a sectional view showing an example of a process for producing a transfer pattern of the present invention, FIG. 2 is a sectional view showing an example of a transfer film of the present invention, and FIG. FIG. 4 is a cross-sectional view showing an example of a diffuse reflection plate manufactured using a transfer film, FIG. 4 is a cross-sectional view showing a manufacturing example of a diffuse reflection plate using the transfer film of the present invention, and FIG. 5 is a cross-sectional view of a reflective LCD. Indicates. FIG. 6 shows a model view of the shape of the transfer prototype of the present invention as viewed from above. In the figure, 1 is a glass substrate, 2 is a thin film layer,
Reference numeral 3 is a reflective film, 4 is a base film, and 5 is a cover film.

The material of the transfer prototype of the present invention is metal, resin, etc.
Although not limited, it is preferable to use an iron alloy such as stainless steel having excellent dimensional stability and conductivity, or a material on which copper or a copper alloy having a processing margin is formed. The surface is mechanically polished,
It is made uniform by etching, washing, etc. Plate-like,
Although it is not limited to a sheet shape, a roll shape, or the like, a roll shape is more preferable because processing can be performed while rotating.

In one example of the method for producing a transfer master of the present invention, first, particles are formed on the master without gaps by a roughening treatment on a mirror-polished copper surface. This rough surface can be formed by a conventionally known method, for example, a method in which a copper sulfate plating solution is plated at a limiting current density or higher or at a low current density, and a roughening treatment is performed, but not particularly limited. A known surface-roughening treatment can be used instead. The surface-roughened particles obtained by this may be particles made of only copper or particles made of other metal or alloy. In some cases, it can be contacted with a soft etching solution to form a rough surface,
It is also possible to spray sandblast or mechanically roughen the surface with a sander belt. If the base material is non-conductive, conductive treatment is performed and rough plating is performed. For the roughening plating, the method shown in the document “Practical plating for field engineers (2)” (published in 1978, edited by Maki Shoten, Japan Plating Association) may be used. Copper plating, nickel plating, It is carried out by a known method such as electroplating such as chrome plating, electroless plating, fine particle eutectoid plating, electrodeposition coating and the like. If the master is in the form of a roll, it is possible to produce a transfer master without unevenness or seams by roughening plating while rotating the roll.

Although the mirror surface-polished copper surface is shown in the examples, an uneven portion in which one or more congruent shapes are arranged adjacently on the surface by electronic engraving, machining, laser processing, etching processing or the like is used. May be formed. The processing methods can also be used in combination.

Leveling plating or bright plating may be carried out for the purpose of filling processing scratches or optimizing the depth of the uneven surface. This is not limited to plating, and may be vacuum vapor deposition or sputtering, or resin or the like may be applied.

After the roughened surface is formed, it is preferable to perform bright plating to level the shape and optimize it. At that time, it is desirable that the plating solution contains a brightening agent. The brightening agent can be selected from those shown in the document “Practical plating for field engineers (2)” (published in 1978, edited by Maki Shoten, Japan Plating Association). An optimum shape can be obtained by adjusting the liquid temperature and the plating time.
It is advisable to carry out leveling plating for a predetermined time or longer under the conditions of current density and plating temperature for bright plating using a nickel plating Watt bath to which saccharin is added as a brightening agent.

Further, protective plating may be performed for the purpose of further increasing the hardness of the surface or preventing oxidation. For this, it is preferable to plate chromium, nickel, zinc or the like.

The transfer base film can be manufactured by pressing a transfer pattern onto a deformable base film. Further, a base film provided with a deformable undercoat layer, formed by a step of pressing a transfer pattern on this layer, and a step of curing the undercoat layer can be used. You may give heat, light, etc. in the process of pressing.

The undercoat layer used in the present invention is preferably harder than the thin film layer after the diffuse reflection surface is formed. Polyolefins such as polyethylene and polypropylene,
Ethylene and vinyl acetate, ethylene and acrylic esters, ethylene and ethylene copolymers such as vinyl alcohol, polyvinyl chloride, vinyl chloride and vinyl acetate copolymers, vinyl chloride and vinyl alcohol copolymers, polyvinylidene chloride , Polystyrene, styrene copolymers such as styrene and (meth) acrylic acid ester, polyvinyltoluene, vinyltoluene copolymers such as vinyltoluene and (meth) acrylic acid ester, poly (meth) acrylic acid ester, (meth ) Copolymers of butyl acrylate and (meth) acrylic acid esters such as vinyl acetate,
Cellulose acetate, nitrocellulose, cellulose derivatives such as cellophane, polyamide, polystyrene, polycarbonate, polyimide, polyester, synthetic rubber,
At least one kind of organic polymer selected from cellulose derivatives and the like can be used.

If necessary, a photoinitiator, a monomer having an ethylenic double bond, or the like may be added in advance for curing after forming the diffuse reflection surface. When a photosensitive resin is used, there is no problem even if the photosensitive type is a negative type or a positive type.

FIG. 7 shows an apparatus for measuring the reflection characteristics of the diffuse reflection plate of the present invention. Assuming that the angle formed by the reflected light ray 21 and the incident light ray 22 is θ, if the brightness observed in the normal direction of the diffuse reflection plate, that is, the reflection intensity is increased within the required θ range, a diffuse reflection plate having excellent reflection characteristics can be obtained. can get.

The base film of the present invention is preferably one which is chemically and thermally stable and can be formed into a sheet or plate. Specifically, polyolefins such as polyethylene and polypropylene, polyvinyl halides such as polyvinyl chloride and polyvinylidene chloride,
Examples thereof include cellulose derivatives such as cellulose acetate, nitrocellulose, cellophane, polyamide, polystyrene, polycarbonate, polyimide, polyester, and metals such as aluminum and copper. Of these, biaxially stretched polyethylene terephthalate, which has excellent dimensional stability, is particularly preferable.

In the present invention, the transfer base film is used as a temporary support, a thin film layer is formed on the surface of the temporary support on which the transfer pattern is transferred, and the surface of the thin film layer not formed on the temporary support is the substrate to be transferred. It can be a transfer film that constitutes the adhesive surface to. Further, the transfer base film is pressed against the thin film layer formed on the substrate so that the transferred surface faces, the transfer base film is peeled off, and a reflective film is formed on the surface to manufacture a diffuse reflection plate. As the thin film layer, a composition containing a deformable organic polymer, an inorganic compound, or a metal can be used, but it is preferable to use an organic polymer composition that can be coated on a support and wound into a film. To use. If necessary, dyes, organic pigments, inorganic pigments, powders and composites thereof may be used alone or in combination.

A photosensitive resin composition or a thermosetting resin composition may be used for the thin film layer. The dielectric constant, hardness, refractive index, and spectral transmittance of these thin film layers are not particularly limited. Among such materials, it is preferable to use one having good adhesion to the transferred substrate and good peelability from the base film. For example, acrylic resin, polyolefin such as polyethylene and polypropylene, polyvinyl halide such as polyvinyl chloride and polyvinylidene chloride, cellulose derivative such as cellulose acetate, nitrocellulose, cellophane, polyamide, polystyrene, polycarbonate, polyimide, polyester and the like are used. be able to. Further, a photosensitive material can be used.
In some cases, a photosensitive resin that can be developed with an alkali or the like may be used so that only the necessary portion of the diffuse reflection surface (transfer surface) of the substrate is left and the unnecessary portion is removed. In order to improve heat resistance, solvent resistance, and shape stability, a resin composition that can be cured by heat or light after forming the diffuse reflection surface can be used. Further, the adhesion with the substrate can be improved by adding a coupling agent and an adhesiveness-imparting agent. An adhesiveness imparting agent may be applied to the adhesive surface of the substrate or the thin film layer for the purpose of improving adhesion.

The alkali-developable resin has an acid value of 20 to 300 and a weight average molecular weight of 1,500 to 20.
It is preferably in the range of 10,000, for example, a copolymer of a styrene monomer and maleic acid or a derivative thereof (hereinafter referred to as an SM polymer), an acrylic acid or methacrylic acid-containing carboxyl group. A copolymer of a saturated monomer and a styrene-based monomer, an alkyl methacrylate such as methyl methacrylate, t-butyl methacrylate, or hydroxyethyl methacrylate, or an alkyl acrylate having a similar alkyl group is preferable.

The SM copolymer is styrene such as styrene, α-methylstyrene, m- or p-methoxystyrene, p-methylstyrene, p-hydroxystyrene, 3-hydroxymethyl-4-hydroxystyrene or a derivative thereof (styrene. Monomers) and maleic anhydride, maleic acid,
Monomethyl maleate, monoethyl maleate, mono-n-propyl maleate, mono-iso-propyl maleate, n-butyl maleate, mono-i maleate.
There are copolymers of maleic acid derivatives such as so-butyl and mono-tert-butyl maleate (hereinafter referred to as copolymer (l)). As the copolymer (l), there are those obtained by modifying the above-mentioned copolymer (l) with a compound having a reactive double bond such as alkyl methacrylate such as methyl methacrylate and t-butyl methacrylate (copolymer). (Ll)).

The above-mentioned copolymer (ll) is an unsaturated alcohol having an acid anhydride group or a carboxyl group in the copolymer (l),
For example, allyl alcohol, 2-bran-1,2-olfurfuryl alcohol, oleyl alcohol, cinnamyl alcohol, 2-hydroxyethyl acrylate, hydroxyethyl methacrylate, unsaturated alcohols such as N-methylolacrylamide, glycidyl acrylate, glycidyl methacrylate, It can be produced by reacting with an epoxy compound having one oxirane ring and one reactive double bond such as allyl glycidyl ether, α-ethyl glycidyl acrylate and itaconic acid monoalkyl monoglycidyl ester. In this case, it is necessary that the carboxyl groups necessary for performing alkali development remain in the copolymer. Polymers having a carboxyl group other than the SM-based polymer are also preferable from the viewpoint of photosensitivity, as in the above case, in which a reactive double bond is added.

The synthesis of these copolymers is described in JP-B-47-2.
It can be carried out according to the methods described in Japanese Patent Publication No. 5470, Japanese Patent Publication No. 48-85679, Japanese Patent Publication No. 51-21572, and the like. If the thin film layer is formed thicker than the height difference of the diffuse reflection surface of the temporary support having the diffuse reflection surface, the shape of the diffuse reflection surface can be easily reproduced. If the film thickness is equal or thin, the shape of the diffuse reflection surface is deformed. Moreover, when forming a diffuse reflection surface, the problem mentioned later may occur.

The coating method of the thin film layer or the undercoat layer of the present invention includes roll coater coating, spin coater coating, spray coating, whaler coating, dip coater coating, curtain flow coater coating, wire bar coater coating, gravure coater coating, air knife coater. Application and the like can be mentioned. The thin film layer or undercoat layer composition is formed on the temporary support or the like by the above method.

In the present invention, a reflective film is formed on the transferred surface of the thin film layer or the transfer base film. An example of forming this reflective film on a thin film layer is shown in FIGS. For the reflective film, a material may be appropriately selected depending on the wavelength region to be reflected. For example, in a reflective LCD display device, a metal having a high reflectance in the visible light wavelength region of 300 nm to 800 nm, such as aluminum, gold or silver. Are formed by a vacuum deposition method, a sputtering method, or the like. Also, a reflection-increasing film (Optical Overview 2 (Junpei Tsujiuchi, Asakura Shoten, 1976)
Yearly issue)) may be laminated by the above method. The thickness of the reflective film is preferably 0.01 μm to 50 μm. Further, the reflection film may be formed by patterning only a necessary portion by a photolithography method, a mask vapor deposition method or the like.

A cover film, which is a protective film, may be provided to protect the surface of the thin film layer transferred to the substrate. The cover film is preferably chemically and thermally stable and can be easily peeled off from the thin film layer.
Specifically, a thin sheet-like material such as polyethylene, polypropylene, polyethylene terephthalate, or polyvinyl alcohol having a high surface smoothness is preferable. The surface may be subjected to a release treatment in order to impart releasability.

The release surface after transfer of each transfer film to the substrate is between the thin film layer and the base film, and when there is a reflective film, between the reflective film and the base film or between the reflective film and the undercoat layer. Becomes However, depending on the purpose, in the case of a film structure having an undercoat layer and a reflective film, since the undercoat layer is laminated on the substrate, the release surface can be set between the undercoat layer and the base film. For the purpose of stacking the undercoat layer on the substrate, the undercoat layer has a function as an electric insulating layer when the reflective film is used as an electrode, or the undercoat layer has a role as a flattening layer of the roughened surface of the reflective film. In the case of using a photosensitive resin for the undercoat layer, and giving a role as an etching resist of the reflective film,
Further, the undercoat layer may be colored so as to partially serve as a light shielding layer of the reflection film.

As a method for transferring the thin film layer on the temporary support and the reflective film to the substrate, the cover film may be peeled off and the substrate may be heated and pressure-bonded. Further, when adhesion is required, a method of washing the substrate with a necessary chemical solution or the like, applying an adhesion-imparting agent to the substrate, or irradiating the substrate with ultraviolet rays or the like may be used. As a device for laminating a transfer film, it is preferable to use a roll laminator that sandwiches a substrate between a rubber roll capable of heating and pressurizing and a base film, rotates the roll, and sends out the substrate while pressing the transfer film against the substrate. .

The thickness of the thin film layer thus formed on the substrate surface is 0. The range of 1 μm to 50 μm is preferable. At this time, if the thickness of the thin film layer is thicker than the maximum height difference of the diffuse reflection surface shape, the diffuse reflection surface shape can be easily reproduced. If the film thickness is equal or thin, it will break through the thin film layer at the convex portion of the prototype,
A flat portion is generated and the efficiency of diffuse reflection is reduced.

When a negative type photosensitive resin is used for this thin film layer, exposure is carried out by an exposure device in order to impart stability of its shape, and the exposed portion is cured. Applicable exposure machines include carbon arc lamps, ultra-high pressure mercury lamps, high pressure mercury lamps, xenon lamps, metal halide lamps, fluorescent lamps, tungsten lamps and the like. This exposure device may be a parallel exposure device for forming patterns of pixels and BM (black matrix), but in the present invention, it is sufficient if the diffuse reflection surface formed in advance can be cured. It is sufficient to give an amount of light equal to or more than the amount of exposure for curing the resin. Therefore, it is possible to use a UV irradiation device that uses scattered light and can be incorporated into a line that is generally used as a substrate cleaning device. By using these devices, the manufacturing cost can be reduced as compared with the method using a photomask, and the margin for the exposure amount is large in comparison with the case where the photomask is used. The above is shown by using a negative type material for the photosensitive type, but there is no problem even if it is a positive type.

The exposure is carried out before or after peeling off the support. A cushion layer may be provided on the base film for the purpose of improving the adhesion to the substrate and the followability. Although the reflection type LCD display device has been described above, the diffuse reflection plate of the present invention can be used for a device that requires diffuse reflection of external light rays. For example, there is a diffuse reflector for the purpose of improving the efficiency of solar cells. Further, the transfer film of the present invention can be used for manufacturing a light shielding plate, a decorative plate, a frosted glass, a white plate of a projection screen, an optical filter, a light collecting plate, a dimming plate and the like. Thus, the transfer film of the present invention can be transferred to a glass plate, a synthetic resin plate, a synthetic resin film, a metal plate, a metal foil, etc., and the transfer target substrate surface may be not only a flat surface but also a curved surface or a three-dimensional surface. .

[0034]

(Example) (Example 1) While a cylindrical iron base material having a diameter of 130 mm is rotated, copper plating is performed, so that iron is coated with copper.
A prototype base material having a stack of 00 μm was obtained. This was polished and processed so that the surface became a mirror surface. Next, while rotating this, it was immersed in the copper plating solution shown below, and the current density (current value per 10 cm 2 of plating area) was 8 A.
After adjusting the current so as to be / square decimeter and performing bright plating, adjusting the current so that the current density is 2 A / square decimeter in the same plating solution, and performing roughening plating, It was washed with pure water for the purpose of removing the plating solution. Next, while immersing in a nickel plating solution shown below, the current was adjusted so that the current density was 2 A / square decimeter, and bright nickel plating was performed to obtain a transfer master. The plating time was 20 minutes. A polyethylene terephthalate film having a thickness of 100 μm was used as a base film, and the following photocurable resin solution was applied onto this base film with a comma coater so as to have a thickness of 20 μm and dried. Next, the transfer prototype is pressed and irradiated with ultraviolet rays to cure the photocurable resin and separated from the transfer prototype to obtain a transfer base film having a diffuse reflection surface shape formed on the surface of the photocurable resin layer (undercoat layer). It was Photocurable resin (undercoat layer) solution: acrylic acid / butyl acrylate / vinyl acetate copolymer 5 parts by weight butyl acetate (monomer) 8 parts by weight vinyl acetate (monomer) 2 parts by weight acrylic acid (monomer) 0.3 parts by weight Hexanediol acrylate (monomer) 0.2 parts by weight benzoin isobutyl ether (initiator) 2.5% by weight Next, a solution for forming a thin film layer is formed on the photocurable resin layer (undercoat layer) with a comma coater so that the average film thickness is 8 μm. The film was coated and dried to a film thickness of, and a polyethylene film was covered as a cover film to obtain a transfer film (FIG. 2). Next, while peeling off the cover film of this transfer film, a laminator (roll laminator HLM1500, trade name of Hitachi Chemical Techno Plant Co., Ltd.) is used so that the thin film layer is in contact with the glass substrate. ,
Laminated at a roll pressure of 0.686 MPa (7 kg / cm ² ) and a speed of 0.5 m / min to form a thin film layer on a glass substrate.
A substrate on which a photocurable resin layer (undercoat layer) and a base film were laminated was obtained. Next, the photocurable resin layer (undercoat layer) and the base film were peeled off to obtain a thin film layer having an uneven surface similar to the uneven shape of the transfer master on the glass substrate. next,
This was heat-cured at 230 ° C. for 30 minutes in an oven, and aluminum thin films were laminated by a vacuum vapor deposition method so as to have a thickness of 0.2 μm to form a reflective layer. When the incident angle dependency of the reflection intensity (gain: relative intensity with respect to the standard white plate) when the azimuth angle (φ) in FIG. 7 is constant was measured, sufficient reflection was obtained in the incident angle range of −20 ° to 20 °. It was possible to obtain a diffuse reflector having high strength and excellent reflection characteristics.

(Solution for forming thin film layer): Styrene, methyl methacrylate, ethyl acrylate as a polymer,
Acrylic acid and glycidyl methacrylate copolymer resin were used (polymer A). The molecular weight is about 35,000 and the acid value is 1.
It is 10. Polymer A 70 parts by weight Pentaerythritol tetraacrylate (monomer) 30 parts by weight Irgacure 369 (Ciba Specialty Chemicals) (initiator) 2.2 parts by weight N, N-tetraethyl-4,4'-diaminobenzophenone (initiator) 2.2 parts by weight Propylene glycol monomethyl ether (solvent) 492 parts by weight p-methoxyphenol (polymerization inhibitor) 0.1 parts by weight Perfluoroalkylalkoxylate (surfactant) 0.01 parts by weight

Example 2 An aluminum thin film was laminated on the diffuse reflection surface (transfer surface) of the transfer base film of Example 1 by vacuum vapor deposition to a thickness of 0.2 μm to form a reflection layer. This was uniform and sufficient reflection intensity was obtained in the incident angle range of −20 ° to 20 °, and a diffuse reflection plate excellent in reflection characteristics was obtained.

(Example 3) Using a glass substrate as a substrate, the same thin film layer forming solution as in Example 1 was applied onto the glass substrate and spin-coated at 2000 rpm for 15 seconds, and then on a hot plate at 90 ° C for 2 minutes. It was heated to form a thin film layer of 8 μm. Then, using a laminator (roll laminator HLM1500, trade name of Hitachi Chemical Technobulant Co., Ltd.) so that the diffuse reflection surface (transfer surface) of the transfer base film of Example 1 faces the thin film layer, the substrate temperature is 90 ° C., and the roll is used. Temperature 80 ℃, Roll pressure 0.686MPa (7kg
/ Cm ² ), the speed was 0.5 m / min, and a substrate was obtained in which a thin film layer, a photocurable resin layer (undercoat layer), and a base film were laminated on a glass substrate. This was irradiated with ultraviolet rays using an exposure device, and then the photocurable resin layer (undercoat layer) and the base film were peeled off to obtain a thin film layer similar to the uneven shape of the transfer master on the glass substrate. Then in the oven 230
After heat-curing at 30 ° C. for 30 minutes, aluminum thin films were laminated by a vacuum deposition method so as to have a thickness of 0.2 μm to form a reflective layer. The obtained diffuse reflection plate had a sufficient reflection intensity in a necessary angle range and was excellent in reflection characteristics.

(Comparative Example 1) As in Example 1, the surface was processed into a mirror surface, and then copper roughening plating similar to that in Example 1 was performed. Bright nickel plating was performed on this for 5 minutes, which was shorter than that in Example 1, to obtain a transfer pattern. A 100 μm-thick polyethylene terephthalate film was used as the base film, and the same photocurable resin solution as in Example 1 was applied and dried on this base film with a comma coater to a film thickness of 20 μm. Next, the transfer prototype is pressed and irradiated with ultraviolet rays to cure the photocurable resin and separated from the transfer prototype to obtain a transfer base film having a diffuse reflection surface shape formed on the surface of the photocurable resin layer (undercoat layer). It was Using a glass substrate as the substrate, the same thin film layer forming solution as in Example 1 was applied onto the glass substrate, spin coated at 2000 rpm for 15 seconds, and heated at 90 ° C. for 2 minutes on a hot plate to 8 μm.
Was formed into a thin film layer. Next, using a laminator (roll laminator HLM1500, trade name of Hitachi Chemical Technoplant Co., Ltd.) so that the uneven surface of the transfer base film faces the thin film layer, the substrate temperature is 90 ° C., the roll temperature is 80 ° C., and the roll pressure is 0.686 MPa. (7 kg / cm ² ), laminating at a speed of 0.5 m / min, a thin film layer on a glass substrate,
A substrate on which a photocurable resin layer (undercoat layer) and a base film were laminated was obtained. This was irradiated with ultraviolet rays by an exposure device, and then the photocurable resin layer (undercoat layer) and the base film were peeled off to obtain a thin film layer similar to the uneven surface shape of the transfer master on the glass substrate. Next, heat curing is performed in an oven at 230 ° C. for 30 minutes, and the aluminum thin film is 0.2 μm by a vacuum deposition method.
The reflective layer was formed by laminating so as to have a thickness of m. This diffuse reflection plate has a high specular reflection component, and sufficient reflection intensity could not be obtained in the incident angle range of 0 to ± 20 °. FIG. 8 shows an electron microscope photograph of the surface of the diffuse reflection plate of Example 1 and FIG. 9 showing that of Comparative Example 1. As seen in the photograph of Comparative Example 1, if the gloss plating is not sufficient, the specular reflection is increased, and the flat portion that causes a defect due to the reflection of the light source remains, so that the specular reflection, that is, the reflection intensity near 0 degrees is high. The reflection intensity distribution was obtained. Example 1 has a shape in which particles having smooth curved surfaces are arranged adjacent to each other without a gap, and in comparison with the comparative example, the distribution of the reflection intensity at −20 to 20 ° other than around 0 ° is sufficient. became. FIG. 5 shows an example of a reflective LCD using a diffuse reflector. By using the diffuse reflection plate of the example, the reflection characteristics became good.

[0039]

EFFECTS OF THE INVENTION The diffuse reflection plate manufactured by using the transfer pattern, the transfer film and the transfer base film of the present invention has good reflection characteristics when used in a reflection type liquid crystal display device and the like. It can be manufactured well. By appropriately designing the diffuse reflection surface in advance, the reflection characteristics of the diffuse reflection plate can be arbitrarily controlled, and the reflection characteristics with good reproducibility can be obtained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a manufacturing process of a transfer prototype of the present invention.

FIG. 2 is a sectional view showing an example of the transfer film of the present invention.

FIG. 3 is a sectional view showing an example of a diffuse reflection plate manufactured using the transfer film of the present invention.

FIG. 4 is a cross-sectional view showing a manufacturing example of a diffuse reflection plate using the transfer film of the present invention.

FIG. 5 is a cross-sectional view of a reflective LCD.

FIG. 6 is a model diagram in which the shape of the transfer prototype of the present invention is observed from above.

FIG. 7 is a perspective view showing a device for measuring the reflection characteristic of a diffuse reflection plate.

8 is an electron micrograph of the diffuse reflection plate of Example 1. FIG.

9 is an electron micrograph of the diffuse reflection plate of Comparative Example 1. FIG.

[Explanation of symbols]

1. Glass substrate 2. Thin film layer 3. Reflective film 4. Base film 5. Cover film 6. Undercoat layer 11. Color filter 12. Black matrix 13. Transparent electrode 14. Flattening film 15. Alignment film 16. Liquid crystal layer 17. Spacer 18. Retardation film 19. Polarizer 20. sample 21. Reflected rays 22. Incident ray 23. Luminance meter

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI Theme Coat (reference) G02F 1/1335 G02F 1/1335 520 520 (72) Inventor Kyoo Tsuruoka 48 Wadai, Tsukuba-shi, Ibaraki Hitachi Chemical Co., Ltd. Stock Company Research Institute (72) Inventor Hidekuni Banno 48 Taidai, Tsukuba, Ibaraki Prefecture Hitachi Chemical Co., Ltd. Research Institute (72) Inventor Keiko Kizawa 48 Taidai, Tsukuba, Ibaraki Hitachi Chemical Co., Ltd. Terms (reference) 2H042 BA03 BA15 BA20 DA02 DA04 DA05 DA11 DB08 DB10 DC02 DC08 DD01 DE00 2H091 FA16Z FB02 FC02 FC06 FC10 FC12 FC23 FC25 FC26 FC29 FC30 FD04 FD15 FD23 GA16 GA17 LA03 LA11 LA12 LA13 LA16 4F202 AG01 AG43 CA19 A22 AA44L AC03 AD32 AG01 AG03 AG05 AG26 AH33 AH78 PA01 PA15 PB01 PC01 PC05 PH02 PH21 PH27 PN09 PQ09 PQ11

Claims (12)

[Claims] 1. A transfer prototype in which the surface of a molding die has a shape in which a large number of spherical crown-shaped particles are arranged adjacent to each other without a gap, and the shape surface is a continuous curved surface. 2. A granular projection is formed on the surface of a molding die,
Furthermore, a method for producing a transfer pattern is formed by a step of plating the surface of which has a leveling effect. 3. A granular projection is formed on the surface of a molding die,
Further, a transfer master formed by a step of plating the surface of which has a leveling effect. 4. A transfer base film in which a shape is transferred by using the transfer master according to claim 1 or 3 and pressing the transfer master against a transfer target film. 5. The transfer base film according to claim 4 is used as a temporary support, a thin film layer is formed on the surface of the temporary support on which the transfer pattern is transferred, and the surface of the thin film layer that is not formed on the temporary support. Is a transfer film that constitutes the adhesive surface to the substrate to be transferred. 6. The transfer film according to claim 5, wherein a reflective film is formed between the temporary support and the thin film layer. 7. A step of pressing the transfer film according to claim 5 on a substrate so that the thin film layer faces, a step of peeling off the temporary support, and forming a reflective film on the transferred surface of the thin film layer. A method for manufacturing a diffuse reflector, which comprises producing the diffuse reflector by steps. 8. A method of manufacturing a diffuse reflection plate, comprising a step of pressing the transfer film according to claim 6 against a substrate so that a thin film layer faces the substrate, and a step of peeling off the temporary support. 9. A step of pressing the transfer base film according to claim 4 against a thin film layer formed on a substrate so that a transferred surface faces the surface, a step of peeling off the transfer base film, and a surface of the transfer base film. A method for manufacturing a diffuse reflection plate, comprising the step of forming a reflection film. 10. A diffuse reflection plate obtained by the method for producing a diffuse reflection plate according to claim 7. 11. A diffuse reflection plate having a reflection film on the surface of the transfer base film according to claim 4 onto which the transfer pattern is transferred. 12. A diffuse reflection plate using the diffuse reflection plate according to claim 10 or 11 in a reflective liquid crystal display.