KR101185055B1 - Soft mold for micro pattern - Google Patents

Abstract

The present invention relates to a soft mold for forming an optical sheet pattern, and more particularly, to a soft mold for forming a microlens and a lenticular lens pattern, and a random pattern on a back surface of a mold in a soft mold for forming a regular pattern. The present invention relates to a soft mold capable of improving the quality of an optical sheet by eliminating the pressing problem caused by foreign matter.

According to the present invention, by providing a cushioning pattern on the back surface formed with the basic pattern of the soft mold to be compressed with the mast roller, to solve the problems such as coating defects due to the pressing of foreign matter, spot stains due to lens formation defects, etc. There is an effect of providing a soft mold that can increase the quality and improve the productivity.

Soft Mold, Shock Absorbing Pattern

Description

Soft mold for fine pattern formation {Soft mold for micro pattern}

The present invention relates to a soft mold for forming an optical sheet pattern, and more particularly, to a soft mold for forming a microlens and a lenticular lens pattern. The present invention relates to a soft mold capable of improving the quality of an optical sheet by eliminating the pressing problem caused by foreign matter.

Apparatus and manufacturing apparatus of optical member having fine shape which can improve handling and yield in continuous mass production of optical member having various micro shape of micro or nano scale, which is used in display or optical element which is recently attracting attention. There is a growing interest in methods and molding molds for the same.

Particularly, among the widely used optical members in display devices, there are diffused films and reflective films used in LCDs. More specifically, such an optical member is used in a backlight unit used in an LCD. The backlight unit includes a light source, a light guide plate, two diffusion plates, and a brightness enhancement film (BEF). In addition to the reflection plate, a mold frame, a protective sheet is further provided.

Many of these optical sheets are components that allow light to be emitted so that the characteristics of light generated from an edge method or a direct method influence the quality of an image, and thus have uniform and high brightness characteristics.

To this end, an optical sheet such as a diffusion film (microlens array film), BEF, etc. is combined, but there is a disadvantage in that the price is expensive, so two diffusion plates are generally used. As described above, the optical sheet used for the diffusion plate used in the backlight is mainly manufactured by using a mold.

That is, the shaping | molding method using a metal mold | die is mainly used for the method of manufacturing an optical film or a plate. Mold production is an important factor for producing optical sheets.

Through the application method of the soft mold used in the conventional molding process of the optical film, the problems of the prior art will be described.

Existing techniques for making molds can be classified into three categories. (1) using a mechanically processed pattern master directly as a mold, (2) a stamper processing method using a metal film electroplated using the pattern master as a base material, and (3) using the above method. There is a method of using a sheet molded with a special resin as a soft mold.

In the case of the direct processing method using the pattern master described above, the pattern shape is mechanically processed on a cylindrical metal surface, and the pattern processed mold is directly mounted on the manufacturing apparatus, and then a material having easy formability is formed between the substrate and the mold. It is a method of injecting and curing it to continuously transfer / apply the shape of the mold surface onto the substrate.

In addition, the stamper processing method is to continuously transfer / apply the shape of the stamper mold onto the substrate by fixing the stamper tightly to the cylindrical metal support surface and then injecting and curing a moldable material between the substrate and the stamper mold. That's the way. In this case, as a method of curing the coating material, heat is directly applied to the mold in order to increase the transferability, and sometimes a material that cures in response to UV ultraviolet rays has been used. In addition, the soft mold method is a method using a sheet molded with a special resin using a conventional mold manufactured by the above two methods as a mold.

However, the above conventional technology has the following problems.

First, the machine operation is difficult to realize the shape of the clean pattern as the size of the pattern is smaller, the cost increases significantly and takes longer as the overall processing area is wider. Next, when the stamper mold is manufactured by electroplating, the stamper manufacturing process of the pattern is not only difficult but also difficult to handle due to the rigid hardness of the produced metal mold, and the unit cost of the raw material of electroplating. Due to the high cost, the production cost is high. Finally, soft molds made of special resins are made of organic materials, which are flexible and easy to handle, but the surface hardness of the special resins is low, resulting in poor durability and shrinkage or expansion when used several times.

With reference to FIG. 1, the application example of the soft mold used for the manufacturing apparatus of the conventional optical member is demonstrated.

The conventional optical member manufacturing apparatus includes a first roll 110 for supplying a base film, a second roll 120 for unloading and winding the completed base film, and a first roll 110 and a second roll ( It is formed of a mast roll 130 is formed between the 120 and the molding mold 142 to form a molding pattern on the base film. In particular, the base film is provided with guide rolls 151 to 156 for smooth transfer thereof. The molding mold 142 is a pattern layer on which a pattern is implemented on a film-shaped base layer, and is generally formed in a belt type. Particularly, the molding mold may be formed of a pattern by a coating liquid injected from the base film. To form. When the base film is inserted onto the molding mold 142 wound on the master roll 130, the member is in close contact with the guide roll 150 and the master roll to form a pattern.

However, the soft mold having such a structure has a relatively thin thickness, so that the base film is wound around the master roll and closely formed during the molding process of a regular pattern such as a micro lens array, a prism, and a lenticular lens. If there is foreign matter on the surface of the master roll, the pressing phenomenon occurs in close contact with the base film, which causes coating defects and spot stains due to lens shape defects. The problem is that the productivity is lowered.

The present invention has been made to solve the above problems, an object of the present invention is to provide a cushioning pattern on the back surface formed with the basic pattern of the soft mold to be compressed with the mast roller, poor coating due to the foreign material, lens formation It is to provide a soft mold that can improve the quality of the optical film and improve the productivity by solving problems such as spots caused by defects.

In order to solve the above problems, in the soft mold used for molding the optical film, a soft pattern for forming a micro pattern, characterized in that a buffer pattern is provided on the back surface of the soft mold on which a basic pattern is formed on the front surface. To provide. In particular, the buffer pattern is disposed in a uniform or non-uniform embossed or intaglio shape, and the buffer pattern may further include an anti-static material.

According to the present invention, by providing a cushioning pattern on the back surface formed with the basic pattern of the soft mold to be compressed with the mast roller, to solve the problems such as coating defects due to the pressing of foreign matter, spot stains due to lens formation defects, etc. There is an effect of providing a soft mold that can increase the quality and improve the productivity.

The present invention provides a soft mold for forming a fine pattern, characterized in that the soft mold used for molding the optical film, the buffer pattern is provided on the back surface of the soft mold, the basic pattern is formed on the front surface, in the molding equipment It is possible to eliminate the occurrence of coating defects, spot spots, etc. on the surface of the optical sheet formed by the foreign matter or environmental foreign matter generated on the surface of the master roll to be provided.

In addition, the present invention provides a soft mold for forming a fine pattern, characterized in that the buffer pattern is formed in the shape of an embossed or intaglio to provide a soft mold having a variety of random patterns.

In addition, the present invention is a soft pattern for forming a fine pattern, characterized in that the buffer pattern is any one selected from among polygonal, polygonal, spherical, elliptical, lenticular, prismatic, or a combination thereof. Make it available.

In addition, the present invention provides a soft mold for forming a fine pattern, characterized in that the buffer pattern is arranged in the same shape or the same size uniformly or non-uniformly, to ensure a variety of manufacturing method, There is an effect that can significantly reduce the occurrence of the defective rate due to foreign matter adhering to the mold backing or foreign matter adhering to the master roll of the molding equipment.

In addition, the present invention is to provide a soft mold for forming a fine pattern, characterized in that the buffer pattern is arranged in a uniform or non-uniform pattern of different shapes or different sizes.

In addition, the present invention can provide a soft mold for forming a fine pattern, characterized in that the size of the buffer pattern is 1 ~ 20㎛.

In addition, the present invention provides a soft mold for forming a micropattern, characterized in that the buffer pattern is formed further comprising an anti-static material, the phenomenon that foreign matter adheres to the molding mold surface by static electricity. Minimize.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the present invention.

The gist of the present invention is to contact the master roll when pressure is applied between the roll and the mast roll to be coated in the "roll type coating process" used in the optical film forming (imprinting) process. The back surface of the soft mold is in close contact, and in this case, a buffer pattern is formed on the back surface of the soft mold for solving the problem of spots or unevenness occurring on the coating surface as the foreign material is pressed.

Referring to FIG. 2, referring to (a), the soft mold according to the present invention is formed with a basic pattern 10 that becomes a mold pattern on the front surface, and the base film 30 on which the pattern is formed has flexibility and tension. Preference is given to using films of strength and durability, such as PET films. Particularly, the portion 20 in which the basic pattern is formed may be curable resin, or the like, and an example may be a polymer material such as an oligomer or a curing initiator. The basic pattern 10 may have a concave pattern in this embodiment. Although described, the shape of the convex pattern can also be implemented.

Referring to FIG. 2B, a buffer pattern 50 having various shapes may be formed on the rear surface of the basic soft mold of FIG. 2A. The buffer pattern 50 may be formed by regularly or irregularly arranging an embossed or intaglio shape on the back surface of the base film 30. In this case, UV resin can be molded and manufactured. In particular, in the shape, the buffer pattern is preferably any one selected from among polygonal, polygonal, spherical, elliptical, lenticular, prismatic, or a combination of those selected from these. Of course, geometric shapes other than these shapes described by way of example can also be applied.

In particular, the shape of the buffer pattern, as shown, it is also possible to form a regular pattern of the same shape, or to form a combination of different shapes. That is, the seamless patterns of the same size or different sizes may be arranged uniformly or non-uniformly. In addition, not only the hemispherical shape as shown in the figure, but also the various shapes described above may be arranged two or more. That is, the buffer pattern may be arranged in a uniform or non-uniform pattern of different shapes or different sizes.

The size of the buffer pattern according to the invention is preferably 1 ~ 20㎛.

In addition, as shown in (c) of FIG. 2, the shape of the pattern may be manufactured as a pattern shape 60 using beads, and in this case, the arrangement of the patterns may be the same size and shape or different size and shape. Of course, it is possible to arrange the buffer pattern with a uniform or non-uniform.

In particular, by adding an antistatic material to the buffer pattern according to the present invention by lowering the surface resistance of the mold to prevent the adhesion of electrostatic foreign matter, it is possible to complete a more excellent buffer pattern.

3 is a photograph showing the overall shape (a) of the buffer pattern according to the present invention, the base pattern surface (b) of the molding mold, and the buffer pattern (c) formed on the back surface of the mold.

In the case of the soft mold formed with the back buffer pattern according to the present invention, the number of spot spots after molding is significantly reduced in comparison with the case where no buffer pattern is formed, so that the quality of the optical sheet can be improved. do.

In the foregoing detailed description of the present invention, specific examples have been described. However, various modifications are possible within the scope of the present invention. The technical idea of the present invention should not be limited to the embodiments of the present invention but should be determined by the equivalents of the claims and the claims.

1 is a schematic diagram of an apparatus for manufacturing an optical member according to the prior art.

2 is a conceptual diagram of a soft mold having a buffer pattern according to the invention of the ball.

3 is a photograph of a soft mold with a buffer pattern according to the present invention.

Claims (7)

In the soft mold used for molding the optical film, Soft pattern for forming a fine pattern, characterized in that the buffer pattern is provided on the back surface of the soft mold in which the basic pattern is formed on the front surface. The method according to claim 1, The buffer pattern is a soft mold for forming a fine pattern, characterized in that formed in the shape of an embossed or intaglio. The method according to claim 2, The buffer pattern is a soft mold for forming a fine pattern, characterized in that the polygonal horn, polygonal, spherical, elliptical, lenticular, prism shape, any one selected from, or a combination of those selected from these. The method according to claim 2, The buffer pattern is a soft mold for forming a fine pattern, characterized in that the same shape or pattern of the same size are arranged uniformly or non-uniformly. The method according to claim 2 The buffer pattern is a soft mold for forming a fine pattern, characterized in that to arrange the pattern of different shape or different size uniformly or non-uniformly. The method according to claim 4 or 5, The size of the buffer pattern is a soft mold for forming a fine pattern, characterized in that 1 ~ 20㎛. The method of claim 6, The buffer pattern is a soft mold for forming a micro pattern, characterized in that it further comprises an anti-static material.

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