JP2011084071A - Flexible forming die - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible forming die capable of easily and inexpensively manufacturing a fine structure including a fine mesh projection pattern or its similar projection pattern formed on the surface with high dimension accuracy and good yield, and simultaneously satisfying high dimension accuracy and good dimension stability, in particular good dimension stability with respect to humidity change. <P>SOLUTION: The flexible forming die includes: a support body comprising a composite material of a polymer material and a reinforcement material; and a shaped layer supported by the support body and having a fine structure surface provided on the surface thereof. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to a molding technique, and more specifically, relates to a flexible mold used for transferring a microstructure pattern in manufacturing a microstructure, a manufacturing method thereof, and a manufacturing method of the microstructure. Although the present invention can be advantageously used for manufacturing various types of microstructures, it can be used particularly advantageously for manufacturing ribs of a back plate for a plasma display panel.

  Recently, a plasma display panel (PDP) has been attracting attention as a flat panel display having a thin and large screen, and has begun to be used as a wall-mounted television for business use or home use.

  A PDP usually includes a large number of fine discharge display cells as schematically shown in FIG. In the illustrated PDP 50, each discharge display cell 56 includes a pair of spaced glass substrates, that is, a front glass substrate 61 and a rear glass substrate 51, and fine-structured ribs arranged with a predetermined shape between these glass substrates. (Also referred to as a barrier rib, partition wall, or barrier) 54. The front glass substrate 61 includes a transparent display electrode 63 composed of a scan electrode and a sustain electrode, a transparent dielectric layer 62, and a transparent protective layer 64 thereon. Further, the rear glass substrate 51 includes address electrodes 53 and a dielectric layer 52 thereon. The display electrode 63 and the address electrode 53 formed of the scan electrode and the sustain electrode are orthogonal to each other and are arranged in a certain pattern with an interval therebetween. Each discharge display cell 56 has a phosphor layer 55 on its inner wall and is filled with a rare gas (for example, Ne—Xe gas), so that self-luminous display can be performed by plasma discharge between the electrodes. Yes.

  In general, the ribs 54 are made of a ceramic microstructure, and are typically provided in advance on the back glass substrate 51 together with the address electrodes 53 and the dielectric layer 52 as schematically shown in FIG. It constitutes a face plate. As the shape of the rib, there are generally a straight pattern and a lattice-like (matrix-like) pattern, but recently, ribs of a lattice-like pattern are becoming mainstream. This is because the ribs of the grid pattern do not leak the ultraviolet rays to the upper and lower cells, so that the vertical resolution is not lowered, and the luminous efficiency is high because the phosphor coating area is large.

A method for forming a straight rib pattern or a lattice rib pattern of a PDP using a mold has already been reported. For example, the following process:
(A) After filling the plate recess of the roll intaglio with an ionizing radiation curable resin (for example, an ultraviolet curable resin) and contacting a flexible film substrate (for example, polyester) with the roll intaglio, A step of curing a resin by irradiation with ionizing radiation to produce a mold sheet having a recess corresponding to the protrusion of the rib;
(B) using the obtained mold sheet as a mold, and filling a concave portion of the mold sheet with a glass paste;
(C) a step of closely attaching the glass substrate to the mold sheet filled with the glass paste, peeling the mold sheet, and transferring the glass paste to the glass substrate; and
(D) firing the transferred glass paste to form ribs;
A method for producing a PDP rib characterized by comprising (Patent Document 1) is known. However, the PDP rib manufacturing method based on such a transfer method has a problem in the configuration of the mold. For example, in the manufacture of PDPs, there is a tendency for PDPs to become larger and discharge display cells to become finer, and it is possible to increase the dimensional accuracy of a mold used for forming ribs and maintain good dimensional stability. Is very important. By the way, in particular, the dimensional stability of the mold is dominated by the properties of the substrate (in the above example, the film substrate) used in the mold. However, organic polymer materials such as polyester, which are generally used as base materials in conventional molds, have large dimensional changes with respect to temperature and humidity changes, so that good dimensional stability of molds can be achieved under various usage environments. It is difficult to achieve with. In fact, even if we can provide a mold that can reproduce the total pitch of ribs (the distance between the left and right or upper and lower outermost ribs) with high accuracy, in order to stably maintain the high accuracy of the mold, Strict temperature and humidity management of the work environment was necessary. Among the dimensional changes to temperature and humidity changes in the mold, especially dimensional changes to humidity changes make it difficult to control the total pitch of the ribs due to slow response speed and difficulty in strict humidity control. One of the biggest causes.

JP-A-8-273537

  Accordingly, the object of the present invention is to easily and inexpensively manufacture a defect-free protrusion pattern, particularly a fine structure having a fine lattice-like protrusion pattern or a similar protrusion pattern on the surface thereof with high dimensional accuracy and high yield. Another object of the present invention is to provide a flexible mold that can simultaneously satisfy high dimensional accuracy and good dimensional stability, in particular, good dimensional stability against changes in humidity.

  Another object of the present invention is to provide a method for producing the above excellent flexible mold easily and inexpensively with high dimensional accuracy and high yield.

  Furthermore, an object of the present invention is to manufacture a microstructure having a defect-free projection pattern, in particular, a fine lattice-like projection pattern or a similar projection pattern on the surface in a simple and inexpensive manner with high dimensional accuracy and high yield. It is to provide a method.

  These and other objects of the present invention will be readily understood from the following detailed description.

The present invention, in one aspect thereof, is a flexible mold used for the transfer of a fine structure pattern in the production of a fine structure,
(1) a support made of a composite material of a polymer material and a reinforcing material;
(2) a shaping layer supported by the support and having a microstructured surface on the surface;
It is in the flexible shaping | molding die for fine pattern transfer characterized by having. Here, the fine structure surface may have either a groove pattern or a protrusion pattern.

  In the specification of the present application, the term “support” is used to distinguish it from the base or base of other molds used in the practice of the present invention. The body is synonymous with the base material of the conventional mold described above.

  The present invention also relates to a flexible mold used for transferring a microstructure pattern in the manufacture of a microstructure, and having a hygroscopic expansion coefficient of less than about 5 ppm / RH%. It is in a mold. In the mold of the present invention, the hygroscopic expansion coefficient is preferably about 3 ppm / RH% or less, more preferably about 1 ppm / RH% or less.

Another aspect of the present invention is a method for producing a flexible mold according to the present invention as described above and described in detail below, comprising the following steps:
A step of preparing a master mold having a projection pattern on the surface having a shape and a dimension corresponding to the microstructure pattern of the microstructure;
Applying a curable resin composition at a predetermined film thickness to the master-shaped pattern forming surface to form a pre-shaped layer;
A step of further laminating a film-like support composed of a composite material of a polymer material and a reinforcing material on the pre-shaped layer to form a laminate including the master mold, the pre-shaped layer and the support;
A step of curing the curable resin composition of the pre-shaped layer, and releasing the shaped layer formed by curing of the curable resin composition together with the support from the master mold, and a support, Producing a flexible mold having a shaping layer with a groove pattern having a shape and a dimension corresponding to the microstructure pattern, the back surface of which is supported by the support;
In the manufacturing method of the flexible shaping | molding die characterized by comprising.

Furthermore, the present invention is a method of manufacturing a microstructure having a microstructure pattern having a predetermined shape and size on the surface of the substrate on the other surface, the following steps:
Providing a flexible mold according to the present invention as described above and described in detail below;
Disposing a curable protrusion-forming material between the substrate and the shaping layer of the flexible mold, and filling the groove pattern of the mold with the protrusion-forming material;
Curing the projection forming material, producing a microstructure comprising the substrate and a projection pattern integrally coupled thereto, and removing the microstructure from the flexible mold;
In the manufacturing method of the fine structure characterized by comprising.

  As will be understood from the following detailed description, the flexible mold provided by the present invention is a microstructure having a defect-free protrusion pattern, particularly a fine lattice-like protrusion pattern or a similar protrusion pattern on the surface. It is suitable for producing a body simply and inexpensively with high dimensional accuracy and good yield, and particularly suitable for producing a PDP rib. In addition, the flexible mold of the present invention is high in dimensional accuracy and good dimensional stability, particularly good against humidity change, in contrast to the mold generally used in the conventional production of PDP ribs and the like. Dimensional stability can be satisfied at the same time.

Further, according to the method of the present invention, the excellent flexible mold as described above can be manufactured easily and inexpensively with high dimensional accuracy and high yield.
Furthermore, according to the method of the present invention, a microstructure having a defect-free projection pattern on its surface, typically a PDP rib, can be manufactured easily and inexpensively with high dimensional accuracy and high yield.
Furthermore, according to the method of the present invention, for example, in the manufacture of PDP ribs, a large number of ribs can be easily and accurately provided at a predetermined position on the substrate in a predetermined pattern with high dimensional accuracy.
In addition, according to the method of the present invention, there is an effect that a PDP rib or other fine structure can be manufactured with high accuracy without defects such as bubble generation and pattern deformation.

It is sectional drawing which showed typically an example of the conventional PDP which can form a rib using the flexible shaping | molding die of this invention. It is the perspective view which showed the backplate for PDP used for PDP of FIG. It is the perspective view which showed one Embodiment of the flexible shaping | molding die by this invention. FIG. 4 is a cross-sectional view taken along line IV-IV of the flexible mold shown in FIG. 3. It is sectional drawing which showed one manufacturing method of the flexible shaping | molding die by this invention later on. It is sectional drawing which showed one manufacturing method of the shaping | molding die for transfer used for manufacture of a flexible shaping die later on in order. It is sectional drawing which showed one method for manufacturing a microstructure using the flexible shaping | molding die produced with the method of FIG. 5 later on. It is a top view of the test composite film which showed the position of the marking for a dimensional change measurement.

  The flexible mold according to the present invention, the manufacturing method thereof, and the manufacturing method of the fine structure can be advantageously implemented in various forms. In the following, the implementation of the present invention will be described in detail with reference to the manufacture of PDP ribs, which are typical examples of microstructures. Needless to say, the present invention is not limited to the production of PDP ribs.

  The PDP rib is as already described with reference to FIG. That is, the ribs 54 of the PDP are provided on the back glass substrate 51 to constitute a PDP back plate. The interval (cell pitch) C between the ribs 54 varies depending on the screen size and the like, but is usually in the range of about 150 to 400 μm. In general, the ribs are required to have two points: “there is no defect such as bubble mixing or deformation” and “pitch accuracy is good”. In terms of pitch accuracy, the rib is required to be provided at a predetermined position with almost no deviation with respect to the address electrode when it is formed, and only a positional error within several tens of μm is actually allowed. When the position error exceeds several tens of μm, the visible light emission conditions are adversely affected, and satisfactory self-luminous display becomes impossible. Today, with the trend toward larger screen sizes, the problem of rib pitch accuracy is serious.

  When the ribs 54 are viewed as a whole, the total pitch of the ribs 54 (distance between the two outermost ribs 54; in the figure, there are five lines) although there are slight differences depending on the size of the substrate and the shape of the ribs. (Only ribs are shown, but usually around 3000) R requires a dimensional accuracy of several tens of ppm or less. In general, it is useful to mold a rib using a flexible mold consisting of a support and a shaping layer with a groove pattern supported by the support. Also, the dimensional accuracy of several tens of ppm or less is required for the total pitch of the mold (distance between the groove portions at both ends) as well as the rib. Of course, such a dimensional accuracy can be easily achieved by using the flexible mold according to the present invention.

  Although the illustrated PDP rib can be manufactured by various methods, it is preferable to make a flexible mold from a master mold having a shape and dimensions corresponding to the rib as described in detail below. And it is preferable to manufacture a rib from the shaping | molding die. However, if desired, a transfer mold may be produced from the master mold, a flexible mold may be produced from the transfer mold, and the rib may be produced from the obtained flexible mold. That is, in the practice of the present invention, the PDP ribs are in the order of master mold-flexible mold-PDP rib, otherwise master mold-transfer mold-flexible mold-PDP rib. Can be advantageously produced. Also, the production of the PDP rib from the flexible mold is preferably produced by a transfer method, that is, by transferring the groove pattern of the flexible mold to the rib forming surface of the substrate. it can. When the flexible mold of the present invention is used, the intended PDP rib can be easily and highly accurately manufactured.

  The present invention firstly resides in a flexible mold used for transferring a fine pattern in the production of PDP ribs and other fine structures. In the practice of the present invention, there are a wide variety of fine structure patterns. However, as described above, the most preferable fine structure pattern is the fine structure pattern of the PDP rib. Therefore, the groove pattern of the flexible mold is usually The straight pattern is composed of a plurality of grooves arranged substantially parallel to each other with a certain interval, or, as shown in FIG. 3, substantially intersects with each other with a certain interval. It consists of a grid pattern configured with a plurality of groove portions arranged in parallel. The rectangular protrusions defined by the adjacent lattice patterns can define the discharge display cells in the finally obtained PDP panel. The flexible mold according to the present invention is like a conventional mold when it is peeled off from a master mold or a transfer mold even if the microstructure pattern is a complicated pattern typified by a lattice pattern. It is worth noting that it does not require a strong peeling force and does not cause damage to the protrusions.

  Further, to explain here, the term “lattice pattern” used for the description of the grid-like ribs does not mean only a typical grid-like pattern as shown in FIG. Also includes similar patterns with a structure close to a lattice. Examples of such a pattern that is effective in the practice of the present invention are not limited to those listed below, but examples include a meander pattern, a waffle pattern, and a rhombus pattern.

FIG. 3 is a perspective view showing a preferred embodiment of the flexible mold according to the present invention, and FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. The flexible mold 20 is, as shown,
(1) a support 21 made of a composite material of a polymer material and a reinforcing material, and (2) a shape and size corresponding to a microstructure structure of a microstructure (not shown) supported on the back surface by the support 21. Shaped layer 22 having groove pattern 24 on its surface
have. The groove pattern 24 is composed of a grid-like groove pattern 24 configured with a plurality of groove portions arranged substantially in parallel while intersecting each other with a predetermined interval. The rectangular protrusions 25 defined by the adjacent lattice groove patterns 24 can define the discharge display cell (reference numeral 56 in FIG. 1) in the finally obtained PDP panel. Although not shown, a primer layer may be provided on the shaping layer side of the support 21 to enhance the adhesive force between the support 21 and the shaping layer 22. If necessary, the shaping layer can have a protrusion pattern on the surface instead of the groove pattern.

The flexible mold of the present invention is made of a composite material of a polymer material and a reinforcing material, for example, a composite material of polypropylene (PP) and glass fiber, in order to satisfy the characteristics required for the support. It is characterized by being used as As will be appreciated from the following detailed description, this is something that was not previously anticipated, but this particular composite material has many properties required for mold supports, such as:
1) Excellent dimensional stability against humidity changes,
2) Good transmission of ionizing radiation such as ultraviolet (UV), electron beam (EB), visible light,
3) High tensile strength,
4) Excellent flexibility for bending,
It is because it can satisfy simultaneously. On the other hand, the glass material can be realized with respect to dimensional stability against changes in humidity, transparency to UV, visible light, etc., and high tensile strength, but it has extremely low flexibility in bending. In addition, a normal organic polymer material can be used for the support, but this material has flexibility, but has a problem in dimensional stability against changes in humidity.

  In the flexible mold according to the present invention, the support has sufficient flexibility (flexibility) and moderate hardness to support the shaping layer and to ensure the flexibility of the mold. As long as it is, the form, the composition of the composite material, the thickness and the like are not limited. In general, a flexible film (reinforced polymer film) of a specific composite material can be advantageously used as a support. The reinforced polymer film is preferably transparent. Particularly when the shaping layer is formed from a photocurable resin composition, ultraviolet rays (UV) and electron beams (EB) irradiated for the purpose of curing when the shaping layer is formed. It is at least necessary to have sufficient transparency to transmit visible light or the like. Furthermore, both the support and the shaping layer are substantially transparent, especially when it is taken into account that the resulting mold is used to produce PDP ribs and other microstructures from photocurable materials. It is preferable that

  In a reinforced polymer film used as a support, in order to control the pitch accuracy of the groove portion of the flexible mold within tens of ppm, a shaping layer forming material involved in the formation of the groove portion (preferably an ultraviolet curable composition) It is preferred to select a composite material that is much harder than a photocurable material) for the reinforced polymer film. In general, the photocuring material has a cure shrinkage of about several percent, so when a soft polymer film is used for the support, the size of the support itself also changes due to the cure shrinkage of the former, and the pitch of the grooves The accuracy cannot be controlled within tens of ppm. On the other hand, if the polymer film used as the support is hard like the reinforced polymer film used in the present invention, the dimensional accuracy of the support itself is maintained even if the photocurable material is cured and shrunk. The accuracy can be maintained with high accuracy. Further, if the polymer film is hard, the pitch fluctuation when forming the rib can be suppressed to be small, which is advantageous in terms of both formability and dimensional accuracy. Further, when the polymer film is hard, the pitch accuracy of the groove portion of the molding die depends only on the dimensional change of the polymer film. Therefore, in order to stably provide a molding die having the desired pitch accuracy, the manufacturing It is sufficient to post-process so that the dimensions of the polymer film in the later mold are as planned and do not change at all.

The hardness of the reinforced polymer film can be expressed by, for example, rigidity against tension, that is, tensile strength. The tensile strength of the reinforced polymer film is usually at least about 5 kg / mm ² and preferably at least about 10 kg / mm ² . When the tensile strength of the reinforced polymer film is less than 5 kg / mm ² , the handling property is lowered when the obtained mold is taken out of the mold or when the PDP rib is taken out of the flexible mold, and it is damaged or pulled. Tearing may occur.

  Examples of polymer materials suitable for forming a reinforced polymer film that is a composite material include, but are not limited to, polyolefins such as polypropylene, cycloolefin, polyvinyl chloride, polystyrene, polycarbonate, and the like. , Polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene naphthalate (PEN), polyether sulfone, polyphenylene sulfide, liquid crystal polymer, and the like. Polymer materials generally used as engineering plastics and super engineering plastics can also be used. In particular, polyolefins such as polypropylene and cycloolefin are useful as the polymer material.

  Furthermore, thermoplastic polymeric materials are also considered advantageous as polymeric materials for forming the support. While certain epoxy resins have been found suitable, other non-thermoplastic (eg, thermosetting) polymeric materials are considered suitable.

  The reinforced polymer film can be produced by blending a predetermined amount of the reinforcing material with the raw material of the polymer material as described above and molding it. The resulting reinforced polymer film can desirably have the advantages of both a polymer material and a reinforcement, dimensional stability against humidity changes, UV, visible light transmission, high tensile strength, bending flexibility. Can be a composite material.

  In the practice of the present invention, various reinforcing materials commonly used in the production of reinforced polymer films can be used in various forms and in various amounts. Suitable reinforcements are, for example, inorganic materials, organic materials, metal materials, fibers such as metal oxides, particles, etc. These materials can be used in the form of mixtures, composites, etc., if necessary. Also good.

  Suitable fibers as the reinforcing material include, for example, glass fibers such as E glass (aluminoborosilicate glass) fibers, carbon fibers, organic fibers, ceramic fibers such as alumina fibers, silica fibers, and metal fibers such as aluminum and stainless steel. , Copper, brass and other fibers. Further, these fibers may be used in the form of a knitted fabric, a nonwoven fabric or the like, if necessary. Further, these fibers may be used in the form of whiskers, continuous fibers, long fibers, short fibers and the like. Further, the reinforcing fibers can be used with various diameters and aspect ratios, for example. The aspect ratio of the reinforcing fiber used here is preferably 3 or more.

  As can be understood from the above, the form of the reinforcing material is various, and therefore the dimensions thereof cannot be defined unconditionally. Taking glass fiber as a typical reinforcing material as an example, when it is a single fiber, its diameter is usually in the range of about 5 to 30 μm, and its length can vary greatly depending on the composite form. is there. Therefore, the form of the reinforcing material made of glass fiber is wide, from a long form made of continuous fiber to a form of short fiber having a length of about 5 mm. Regarding the general dimensions of the reinforcing materials listed above and other reinforcing materials, many reports have already been made, so please refer to the book.

  The reinforcing material as described above can be blended in various amounts with respect to the polymer material, but is usually in the range of about 20 to 70% by volume based on the total amount of the composite material. If the compounding amount of the reinforcing material is less than 20% by volume, the compounding effect of the reinforcing material cannot be expressed sufficiently. On the contrary, if the compounding amount exceeds 70% by volume, defects such as a decrease in flexibility of the film become conspicuous. .

In the flexible mold of the present invention, the composite material of the support can be completed with various combinations of polymer materials and reinforcements as described above. Some of the combinations suitable for the practice of the present invention are listed, for example:
A) A combination of polypropylene and glass fiber,
B) A combination of cycloolefin and glass fiber,
C) A combination of polyphenylene sulfide and glass fiber,
D) Combination of liquid crystal polymer and glass fiber,
And so on.

  The reinforced polymer film may be used as a single layer film when it is used as a support, or may be used as a composite or laminated film in combination of two or more if necessary. In any case, the support made of the reinforced polymer film can be used in various thicknesses depending on the flexible mold and the structure of the PDP, but usually in the range of about 50 to 1,000 μm. Yes, preferably in the range of about 100-400 μm. When the thickness of the support is less than 50 μm, the rigidity of the film becomes too low and wrinkles and folds are likely to occur. On the other hand, when the thickness of the support exceeds 1,000 μm, the flexibility of the film decreases, and the handleability decreases.

  A reinforced polymer film is usually a sheet of polymer raw material and reinforcing material formed by a technique such as calendering or coating, and can be manufactured in a state of being cut into a sheet form or wound up on a roll. Otherwise, it is commercially available. If necessary, an optional surface treatment may be applied to the reinforced polymer film to improve the adhesion strength of the shaping layer to the reinforced polymer film. Examples of suitable surface treatment include primer treatment. If necessary, the primer treatment may be performed on site during the production of the mold. The primer treatment can be performed according to a conventional method.

  In the flexible mold, the shaping layer provided on the support as described above can be variously configured according to the desired effect. In general, the shaping layer is preferably made of a cured product of the curable resin composition. The curable resin composition may be photocurable or thermosetting, but is preferably a photocurable resin composition. Such a resin composition can be cured into a shaping layer by a crosslinking reaction or other curing mechanism by irradiating various ionizing radiations such as ultraviolet rays (UV), electron beams (EB), and visible rays. The UV curable resin composition can be advantageously used for forming the shaping layer because of its availability and easy curing reaction. In the following, the formation of the shaping layer will be described with reference to the ultraviolet curable resin composition in particular, but it goes without saying that other photocurable resins can be used as necessary.

  Although the ultraviolet curable resin composition can have various compositions, it preferably contains an acrylic monomer and / or an oligomer as a main component. Moreover, it is preferable that the cured resin derived from this ultraviolet curable composition has a glass transition point of about 0 ° C. or lower.

  The shaping layer is preferably composed of a cured resin formed by curing an ultraviolet curable composition containing an acrylic monomer and / or oligomer as a main component by irradiation with ultraviolet rays. In forming it from an ultraviolet curable composition, it is useful because a cured resin can be obtained by curing in a relatively short time without requiring a long heating furnace.

  Acrylic monomers suitable for forming the shaping layer are not limited to those listed below, but include urethane acrylate, polyether acrylate, polyester acrylate, acrylamide, acrylonitrile, acrylic acid, acrylic acid ester, and the like. Can be mentioned. In addition, examples of the acrylic oligomer suitable for forming the shaping layer include, but are not limited to, those listed below, such as urethane acrylate oligomer, polyether acrylate oligomer, polyester acrylate oligomer, and epoxy acrylate oligomer. Can do. In particular, urethane acrylate and oligomers thereof can provide a flexible and tough cured resin layer after curing, and can also contribute to the improvement of the productivity of the mold because the curing speed is extremely fast among acrylates in general. Furthermore, when these acrylic monomers and oligomers are used, the shaping layer becomes optically transparent. Therefore, a flexible mold provided with such a shaping layer is also useful in that a photo-curable molding material can be used when manufacturing PDP ribs and other fine structures.

  The acrylic monomers and oligomers as described above may be used alone or in combination of two or more kinds depending on the desired mold configuration and other factors. The inventors have found that particularly favorable results are obtained when the acrylic monomer and / or oligomer is a mixture of a urethane acrylate oligomer and a monofunctional and / or bifunctional acrylic monomer. Further, in such a mixture, the mixing ratio of the urethane acrylate oligomer and the acrylic monomer can be changed in a wide range, but usually, the urethane acrylate oligomer is about 20 to 80 wt% based on the total amount of the oligomer and the monomer. It is preferably used in an amount of%. Since the urethane acrylate oligomer and the acrylic monomer can be mixed in such a wide range in the obtained mold, the viscosity of the ultraviolet curable composition for forming the shaping layer can be set to a wide range suitable for molding. Therefore, when the mold is manufactured, it is possible to achieve improvements such as easy work and a constant film thickness.

  The ultraviolet curable composition can optionally contain a photopolymerization initiator and other additives as necessary. For example, the photopolymerization initiator includes 2-hydroxy-2-methyl-1-phenylpropan-1-one and the like. Although the photopolymerization initiator can be used in various amounts in the ultraviolet curable composition, it is usually an amount of about 0.1 to 10% by weight based on the total amount of the acrylic monomer and / or oligomer. Is preferably used. When the amount of the photopolymerization initiator is less than 0.1% by weight, there arises a problem that the curing reaction is remarkably slow or sufficient curing cannot be obtained. On the contrary, when the amount of the photopolymerization initiator is more than 10% by weight, the unreacted photopolymerization initiator remains even after the completion of the curing process, such as yellowing or deterioration of the resin, shrinkage of the resin due to volatilization, etc. A problem occurs. Examples of other useful additives include an antistatic agent.

  In forming the shaping layer, the ultraviolet curable composition can be used at various viscosities (Brookfield viscosity, so-called B viscosity), but the preferred viscosity is usually in the range of about 10 to 35,000 cps. And more preferably in the range of about 50 to 10,000 cps. When the viscosity of the ultraviolet curable composition is out of the above range, problems such as difficulty in forming a film in forming the shaping layer and insufficient progress of curing may occur.

  Although the shaping layer can be used in various thicknesses depending on the configuration of the flexible mold and the PDP, it is usually in the range of about 5 to 1,000 μm, preferably about 10 to 800 μm. More preferably, it is in the range of about 50 to 700 μm. When the thickness of the shaping layer is less than 5 μm, there arises a problem that a necessary rib height cannot be obtained. The shaping layer of the present invention causes inconvenience in removing the flexible mold from the master mold or the transfer mold even when the thickness is increased to 1,000 μm in order to guarantee a large rib height. However, if the thickness of the shaping layer is further larger than 1,000 μm, the stress increases due to curing shrinkage of the ultraviolet curable composition, causing problems such as warpage of the mold and deterioration of dimensional accuracy. In the mold according to the present invention, even if the depth of the groove pattern corresponding to the height of the rib, in other words, the thickness of the shaping layer is designed to be large, the work for removing the completed mold from the master mold is small. It is important that it can be implemented easily with force.

  The groove pattern formed on the surface of the shaping layer will be described. The depth, pitch and width of the groove pattern are the thickness of the target PDP rib pattern (straight pattern or grid pattern) and the shaping layer itself. However, in the case of the flexible mold for the grid-like PDP rib shown in FIGS. 3 and 4, the depth of the groove pattern (corresponding to the height of the rib) is usually , Preferably in the range of about 150-300 μm, and the pitch of the groove pattern, which may be different in the vertical and horizontal directions, is usually in the range of about 100-600 μm, Preferably, it is in the range of about 200 to 400 μm, and the width of the groove pattern which may be different between the upper surface and the lower surface is usually in the range of about 10 to 100 μm, preferably about 5 It is in the range of 0 to 80 μm.

The present invention secondly resides in a method for producing the flexible mold of the present invention as described above. Although the method for producing a flexible mold according to the present invention can be carried out in various processes, preferably, the following steps are performed:
A step of preparing a master mold having a protrusion pattern having a shape and a dimension corresponding to a microstructure pattern of a microstructure as a final object;
Applying a curable resin composition at a predetermined film thickness to the master-shaped pattern forming surface to form a pre-shaped layer;
A step of further laminating a film-like support composed of a composite material of a polymer material and a reinforcing material on the pre-shaped layer to form a laminate including the master mold, the pre-shaped layer and the support;
A step of curing the curable resin composition of the pre-shaped layer, and releasing the shaped layer formed by curing of the curable resin composition together with the support from the master mold, and a support, Producing a flexible mold having a shaping layer with a groove pattern having a shape and a dimension corresponding to the microstructure pattern, the back surface of which is supported by the support;
Can be advantageously carried out in a process comprising: In addition, the “pre-shaped layer” in the method of the present invention is a precursor of a shaped layer that can be converted into a shaped layer by curing.

  The method of the present invention can be advantageously implemented in various ways. For example, according to a preferred embodiment, a master mold having a projection pattern having a shape and a dimension corresponding to the fine structure pattern of the fine structure on the surface can be used as a mother mold of the flexible mold. When the fine structure is a PDP rib, a fine protrusion pattern having a shape and a dimension corresponding to the rib is provided on the surface of the master mold. The master mold is manufactured by, for example, forming a fine protrusion pattern corresponding to a rib on a metal flat plate such as a brass plate by electrical, mechanical and / or physical processing such as end milling, electric discharge machining, and ultrasonic grinding. can do. Of course, the master mold used in the practice of the present invention is not limited to metal, and may be made of ceramic, gypsum, or the like.

  According to another preferred embodiment, a flexible mold is first produced from the master mold, and then a flexible mold is produced from the transfer mold without directly producing the flexible mold from the master mold. You can also That is, according to this aspect, a master mold having a groove pattern having a shape and a dimension corresponding to the fine structure pattern of the fine structure on the surface is prepared, and a transfer mold is manufactured by transferring the groove pattern of the master mold. To do. As can be easily understood, the master mold used in this case is, for example, a metal flat plate such as a brass plate, a fine groove pattern corresponding to ribs, electrical, mechanical and so on such as end mill, electric discharge machining, and ultrasonic grinding. (Or) can be manufactured by physical processing. In this method, an intermediate transfer mold can be used repeatedly, so that it can be used as a substantial mother mold for manufacturing a flexible mold. The troublesome and uneconomic problems of producing a large number of master molds for use as a mother mold can be overcome. Furthermore, since the production of the master mold used in this aspect of the present invention is only required to process the groove pattern, it is simpler than the process of the projection pattern and has an economic advantage.

  The pre-shaped layer forming step can be carried out using a photocurable or thermosetting resin composition as described above, but preferably using a photocurable resin composition. In particular, it can be advantageously carried out using an ultraviolet curable resin composition. The ultraviolet curable resin composition is preferably an ultraviolet curable composition containing an acrylic monomer and / or an oligomer as a main component. In addition, when the preshaped layer is composed of a photocurable resin composition, the photocurable resin composition can be cured by various techniques, but it passes through the support on which the preshaped layer is laminated. It is advantageous to form a shaping layer by curing with applied light. Furthermore, in order to increase the adhesive force between the support and the shaping layer, a primer layer may be provided in advance on the pre-shaped layer side of the support, if necessary. The primer layer can be formed, for example, from a primer composition “K-500” commercially available from 3M Company.

  The flexible mold can be manufactured according to various techniques as described above. For example, it can be advantageously manufactured by a procedure as shown in order in FIG. In the figure, the microstructure to be manufactured is a PDP rib.

  First, as shown in FIG. 5A, a master mold 1 having a shape and dimensions corresponding to the PDP rib is manufactured. The master mold 1 can be produced, for example, by machining a stainless steel plate. The master mold 1 is provided with partition walls 4 having the same pattern and shape as ribs of the back plate for PDP on its surface, and accordingly, cavities (recesses) 5 defined by the adjacent partition walls 4 are formed in a PDP discharge display cell. It becomes. A taper for preventing foaming may be attached to the upper end portion of the partition wall 4. In addition to the master mold 1, a support (hereinafter referred to as a support film) 21 made of a transparent polymer film and a laminate roll 23 are prepared. The laminate roll 23 presses the support film 21 against the master mold 1 and is made of a rubber roll. If necessary, other known and conventional laminating means may be used in place of the laminating roll. As described above, the support film 21 is made of a transparent reinforced polymer film.

  Next, a predetermined amount of the ultraviolet curable molding material 3 is applied to the end face of the master mold 1 by a known / common coating means (not shown) such as a knife coater or a bar coater. The ultraviolet curable molding material is for forming a shaping layer of the resulting flexible mold. Here, when a material that is flexible and tensile with respect to bending and rigid with respect to compression is used as the support film 21, even if the ultraviolet curable molding material 3 contracts, it is in close contact with the support film 21, Unless the support film itself is deformed, dimensional fluctuations of 10 ppm or more will not occur.

  In order to remove the dimensional change due to the humidity of the support film before the laminating treatment, it is preferable to perform aging in the production environment of the mold. If this aging treatment is not performed, there is a risk that dimensional variations (for example, variations on the order of 300 ppm) that cannot be tolerated in the obtained mold may occur.

  Next, the laminate roll 23 is slid on the master mold 1 in the direction of the arrow. As a result of the laminating process, the molding material 3 is uniformly distributed with a predetermined thickness, and the gaps of the partition walls 4 are also filled with the molding material 3. Moreover, since the molding material 3 is spread with the support film 21, compared with the coating method generally used conventionally, the fall off is also favorable. The molding material 3 in this state is the pre-shaped layer referred to in the present invention.

  After the laminating process is completed, as shown in FIG. 5B, with the support film 21 laminated on the master mold 1, ultraviolet light (hν) is pre-applied as indicated by an arrow through the support film 21. The shape layer 3 is irradiated. Here, if the support film 21 is uniformly formed of a transparent material without including light scattering elements such as bubbles, the irradiation light hardly reaches attenuation and reaches the pre-shaped layer 3 evenly. Is possible. As a result, the molding material of the pre-shaped layer 3 is cured efficiently and becomes a uniform shaped layer 22 adhered to the support film 21. Therefore, the flexible mold 20 in which the support film 21 and the shaping layer 22 are integrally joined is obtained. In this step, for example, ultraviolet rays having a wavelength of 350 to 450 nm can be used, so that there is an advantage that it is not necessary to use a light source that generates high heat like a high pressure mercury lamp such as a fusion lamp. Furthermore, since the support film and the shaping layer are not thermally deformed during UV curing, there is also an advantage that a high degree of pitch control can be performed.

  Thereafter, as shown in FIG. 5C, the flexible mold 20 is separated from the master mold 1 while maintaining its integrity.

  The flexible mold according to the present invention can be manufactured relatively simply by using well-known and conventional laminating means and coating means corresponding to the dimensions and sizes. Therefore, according to the present invention, unlike a conventional manufacturing method using vacuum equipment such as a vacuum press molding machine, a large flexible mold can be easily manufactured without any limitation.

  In addition, the flexible mold is useful in the production of various microstructures. For example, the flexible mold is useful for forming a rib of a PDP having a straight rib pattern or a lattice rib pattern. If this flexible mold is used, a large-screen PDP having a rib structure that prevents leakage of ultraviolet rays from the discharge display cell to the outside simply by using a laminate roll instead of vacuum equipment and / or a complicated process can be easily performed. Can be manufactured.

  Furthermore, the flexible mold is particularly useful when a plurality of ribs are arranged substantially in parallel with each other while intersecting each other at regular intervals, that is, when a lattice-shaped PDP rib is manufactured. Although this flexible mold is a mold for manufacturing ribs having a large and complicated shape, the operation of removing the flexible mold from the master mold is not limited to deformation, destruction, etc. of the mold. This is because it can be carried out easily without causing the above problem.

  FIG. 5 described above is an example in which a flexible mold is manufactured from a master mold. According to another method, as described above, it is also possible to produce a transfer mold from a master mold, and then to produce a flexible mold from this transfer mold. Hereinafter, a method for producing a flexible mold from a transfer mold will be described.

The transfer mold (hereinafter abbreviated as “transfer mold”) can have, for example, a structure schematically shown in FIG. As shown in FIG.
(1) a base 11 made of a hard material having a high elastic modulus, and (2) a shape and size corresponding to a fine structure pattern (a fine PDP rib pattern in the figure) of the fine structure supported by the base 11. A transfer pattern layer 12 having a projection pattern 14 on the surface thereof,
have. In the transfer mold 10, the transfer pattern layer 12 can be preferably formed from a two-component room temperature curable silicone rubber that is a specific silicone rubber.

  In the transfer mold as shown, the base is made of a hard material having a high elastic modulus. Such a hard material makes it possible to maintain the high dimensional accuracy of the master mold as it is when a transfer mold (transfer mold) is produced from the master mold. That is, when the transfer pattern layer forming material is applied and cured on the master mold, the transfer pattern layer forming material is cured and contracted, so that the dimensional accuracy of the obtained transfer pattern is generally accurately maintained. However, it is difficult to maintain a high dimension by using a hard material having a high elastic modulus as a base.

  Hard materials suitable for the base include a wide range of materials from metallic materials to plastic materials, but metallic materials are particularly useful. Suitable metal materials are not limited to those listed below, but examples include stainless steel and copper. These metal materials may be used alone or, if desired, in the form of an alloy.

  The base is usually used in the form of a sheet or plate made of a single hard material, but may be used in the form of a composite or a laminate if desired. Although the thickness of the base can be changed in a wide range depending on the specifications of the transfer mold, it is usually in the range of about 0.1 to 5 mm, more preferably in the range of about 0.5 to 3 mm. is there. If the thickness of the base is thinner than 0.1 mm, the handling property of the transfer mold is lowered, and it becomes difficult to maintain the high dimensional accuracy of the master mold. For example, when a PET film is used as a base instead of a metal plate having a predetermined thickness, the transfer mold becomes light, but it becomes difficult to maintain high dimensional accuracy anymore. On the other hand, when the thickness of the transfer mold exceeds 5 mm, the handleability of the transfer mold deteriorates due to the increase in weight.

  The transfer pattern layer supported by the base is formed from a two-component room temperature curable silicone rubber. When using such silicone rubber to form a transfer pattern layer, it is necessary to heat-treat the base and master mold unlike thermosetting resins generally used for conventional film formation purposes. Therefore, it is possible to avoid deformation caused by heating and a decrease in dimensional accuracy due to the deformation. In addition, it is conceivable to form a transfer pattern layer using a photo-curing resin or a moisture-curing resin instead of a thermosetting resin having a difficulty, but in the case of such a curable resin, light transmission is possible. Since it is used by sandwiching it between a master mold having no property and a base, it is substantially impossible to cure in a complete form.

  In addition, since the two-component room temperature curable silicone rubber has low surface energy and flexibility, the operation of peeling the transfer mold (transfer mold) from the master mold and the transfer mold according to the present invention. The work of peeling the flexible mold is extremely easy.

  Furthermore, the two-pack room temperature curable silicone rubber can be cured in a few hours. For this reason, a transfer mold can be manufactured in a cycle of several hours, although the conventional method requires a very long time for manufacturing the transfer mold. That is, according to this method, it is possible to manufacture any number of transfer molds having a convex pattern of a lattice or other shapes in a cycle of several hours. Furthermore, since the transfer mold produced in this way has strength and the like that the transfer pattern layer can be used repeatedly, it can be used repeatedly as a substantial mother mold instead of the conventional master mold. Can do.

  The thickness of the transfer pattern layer can be changed in a wide range depending on the specifications of the transfer mold and other factors, but is usually in the range of about 0.005 to 10 mm, preferably about 0.005. It is the range of 02-0.2 mm. When the thickness of the transfer pattern layer is less than 0.005 mm, it becomes difficult to apply the projection pattern to the surface of the layer. Conversely, when the thickness of the transfer pattern layer exceeds 10 mm, the material cost increases. Further, there is no merit of forming the transfer pattern layer thin.

  Furthermore, since the above-mentioned transfer mold can use a master mold having a groove pattern (concave pattern) having a shape and a dimension corresponding to the fine structure pattern of the fine structure on the surface, the master mold can be processed. There is also an effect that it can be carried out easily and in a relatively short time. In the case of producing a master mold having a projection pattern on the surface as in the prior art, it is an object that long processing, skill, and a great deal of cost were required. In fact, when processing the grid-like concave pattern into a metal plate, etc., and when machining the grid-like convex pattern into the same metal plate, etc., it is clear in the fineness, processing time, cost, etc. The difference comes out.

  In addition, when a fine structure (for example, a PDP rib) is produced directly by transfer from a master mold having a concave pattern on the surface as in the prior art, a protrusion (for example, a rib) is damaged. Although problems arise, this method of the present invention also avoids this problem because it uses a transfer mold. In short, according to the present invention, when a lattice-like PDP rib, which is a typical example of a fine structure, is desired to be manufactured, a master die having a lattice-like recess pattern that can be easily processed can be used as a mother die, and A grid-like rib can be formed without causing a rib defect.

The transfer mold can be produced using various techniques, but preferably the following steps:
Forming a transfer pattern layer having a protrusion pattern having a shape and a dimension corresponding to a microstructure structure of a target microstructure on the surface from a two-component room temperature curable silicone rubber; and a back surface of the transfer pattern layer. It can be manufactured by a method including a step of supporting by a base made of a hard material having a high elastic modulus.

Further, in the implementation of this manufacturing method, the groove pattern of the master mold is transferred to the silicone rubber from a master mold having a groove pattern having a shape and a dimension corresponding to the microstructure structure pattern of the microstructure on the surface. It is preferable to form a protrusion pattern of the transfer pattern layer. Specifically, the following steps:
A step of forming a precursor layer of the transfer pattern layer by applying a two-component room temperature curable silicone rubber with a predetermined film thickness to the surface of the master mold;
Laminating the base on the master mold to form a laminate including the master mold, a precursor layer of the transfer pattern layer, and the base;
Curing the silicone rubber, and releasing the transfer pattern layer formed by curing the silicone rubber together with the base from the master mold,
By sequentially carrying out the steps, the intended transfer mold can be manufactured.

FIG. 6 shows one preferred method for producing a transfer mold.
First, a master mold 1 as shown in FIG. The master die 1 is made of, for example, a stainless steel flat plate, and has a groove pattern 4b having a shape and a dimension corresponding to the fine structure pattern of the fine structure on the surface thereof.

  Next, as shown in FIG. 6B, a two-component room temperature curable silicone rubber 2 used as a precursor of a transfer pattern is applied to the surface of the prepared master mold 1 with a predetermined film thickness. In the illustrated example, the room temperature curable silicone rubber 2 is applied to the surface of the master mold 1 and the groove pattern 4b is sequentially filled, but other methods may be adopted. For example, a room temperature curable silicone rubber processed into a sheet shape may be prepared, and this may be laminated on the pattern surface of the master mold so as to adhere both. Further, according to another method, after the master mold and the base of the transfer mold (described above) are arranged at a predetermined interval, room temperature curable silicone rubber may be injected into the gap. In any method, the precursor 2 of the transfer pattern layer can be formed with a predetermined thickness.

  Subsequently, as shown in FIG. 6C, a transfer mold base 11 is laminated on the master mold 1 to form a laminate including the master mold 1, a transfer pattern layer precursor and the base 11. To do. In the figure, the transfer pattern layer 12 formed by curing the precursor is shown. In other words, when the precursor room temperature curable silicone rubber is cured, a transfer mold 10 comprising a base 11 and a transfer pattern layer 12 supported by the base 11 is obtained as shown in the figure. The room temperature curable silicone rubber can usually be cured in several hours at room temperature.

  Finally, although not shown, the obtained transfer mold is released from the master mold. The mold after release may be after-cured at room temperature or elevated temperature if necessary. This transfer mold can be advantageously used as an alternative to the master mold 1 in the method of manufacturing a flexible mold described above with reference to FIG. 5 for producing a flexible mold.

The present invention thirdly resides in a method for manufacturing a fine structure. This manufacturing method may be carried out through any process as long as the flexible mold of the present invention is used. In fact, the method of the present invention can be advantageously carried out through various steps.
The method for producing a microstructure according to the present invention preferably comprises the following steps:
A step of preparing a flexible mold according to the present invention;
Disposing a curable protrusion forming material between the substrate of the microstructure and the shaping layer of the flexible mold, and filling the groove pattern of the flexible mold with the protrusion forming material;
Curing the projection forming material, producing a microstructure comprising the substrate and a projection pattern integrally coupled thereto, and removing the microstructure from the flexible mold;
Can be advantageously carried out by sequentially carrying out. The curable protrusion forming material is preferably a photocurable material.

  The microstructure manufacturing method of the present invention can be advantageously used in the production of PDP ribs. That is, the PDP rib can be advantageously produced using the flexible mold of the present invention produced as described above or using other methods. Hereinafter, a method of manufacturing a PDP rib having a grid-like rib pattern using the flexible mold 20 manufactured by the method of FIG. 5 will be described in order with reference to FIG. For the implementation of this method, for example, the manufacturing apparatus shown in FIGS. 1 to 3 of JP-A-2001-191345 can be advantageously used.

  First, although not shown, a glass flat plate having striped electrodes arranged on the upper surface in a predetermined pattern is prepared and set on a surface plate. Next, as shown in FIG. 7A, the flexible mold 20 having the groove pattern on the surface is placed at a predetermined position on the glass flat plate 31, and the glass plate 31 and the mold 20 are aligned (aligned). )I do. Here, the glass flat plate 31 has an address electrode and a dielectric layer as shown in FIG. 2, but is omitted for simplification of description. Since the shaping | molding die 20 is transparent, position alignment with the electrode on the glass flat plate 31 is easily possible. Specifically, this alignment may be performed visually, or may be performed using a sensor such as a CCD camera. At this time, if necessary, temperature and humidity may be adjusted so that the gaps between adjacent grooves on the mold plate 20 and the glass flat plate 31 are matched. This is because the mold 20 and the glass flat plate 31 usually expand and contract according to changes in temperature and humidity, and the extents thereof are different from each other. Therefore, after the alignment between the glass flat plate 31 and the mold 20 is completed, the temperature and humidity at that time are controlled to be kept constant. Such a control method is particularly effective in manufacturing a large-area PDP substrate.

  Subsequently, the laminating roll 23 is placed on one end of the mold 20. The laminate roll 23 is preferably a rubber roll. At this time, it is preferable that one end of the mold 20 is fixed on the glass flat plate 31. This is because misalignment between the glass flat plate 31 and the mold 20 that have been previously aligned can be prevented.

  Next, the free other end of the mold 20 is lifted by a holder (not shown) and moved above the laminating roll 23 to expose the glass flat plate 31. At this time, no tension is applied to the mold 20. This is to prevent wrinkles from entering the mold 20 and to maintain the alignment between the mold 20 and the glass flat plate 31. However, other means may be used as long as the alignment can be maintained. In the present manufacturing method, since the molding die 20 is elastic, even if the molding die 20 is raised as shown, it can be accurately returned to the original alignment state at the time of subsequent lamination.

Subsequently, a predetermined amount of rib precursor 33 necessary for rib formation is supplied onto the glass flat plate 31. For supplying the rib precursor, for example, a paste hopper with a nozzle can be used.
Here, the rib precursor means any molding material capable of finally forming a target rib molded body, and is not particularly limited as long as the rib molded body can be formed. The rib precursor may be thermosetting or photocurable. In particular, the photocurable rib precursor can be used very effectively in combination with the above-described transparent flexible mold. As described above, the flexible mold is hardly accompanied by defects such as bubbles and deformation, and can suppress uneven scattering of light and the like. Thus, the molding material is uniformly cured and becomes a rib having a constant and good quality.

  An example of a composition suitable for the rib precursor is as follows: (1) giving a rib shape, for example, a ceramic component such as aluminum oxide; (2) filling gaps between the ceramic components to give the ribs denseness. It is a composition that basically includes a glass component such as lead glass or phosphate glass, and (3) a binder component that contains and holds the ceramic component and is bonded to each other and its curing agent or polymerization initiator. It is desirable that the binder component is cured by light irradiation regardless of heating or heating. In such a case, it is not necessary to consider the thermal deformation of the glass flat plate.

  Further, in the implementation of the illustrated manufacturing method, the rib precursor 33 is entirely supplied to the upper surface of the glass flat plate 31. The rib precursor 33 generally has a viscosity of about 20,000 cps or less, preferably about 5,000 cps or less. When the viscosity of the rib precursor is higher than about 20,000 cps, the rib precursor is not easily spread by the laminate roll, and as a result, air may be caught in the groove portion of the mold, which may cause rib defects. . In fact, if the viscosity of the rib precursor is about 20,000 cps or less, the rib precursor is moved between the glass plate and the mold only by moving the laminate roll from one end of the glass plate to the other end only once. It spreads uniformly and can be filled uniformly without bubbles in all the grooves.

  Next, a rotary motor (not shown) is driven, and the laminate roll 23 is moved on the mold 20 at a predetermined speed as indicated by an arrow in FIG. While the laminating roll 23 is moving on the mold 20 in this manner, pressure is sequentially applied to the molding mold 20 from one end to the other end by the weight of the laminating roll 23 to form the glass flat plate 31 and the mold. The rib precursor 33 spreads between the molds 20 and fills the grooves of the mold 20. That is, the rib precursor 33 is sequentially replaced with the air in the groove and filled. At this time, the thickness of the rib precursor can be set in the range of several μm to several tens of μm by appropriately controlling the viscosity of the rib precursor or the diameter, weight or moving speed of the laminate roll.

  In addition, according to the illustrated manufacturing method, the groove portion of the mold also serves as an air channel, and even when air is trapped there, the air is efficiently removed from the outside or the periphery of the mold when the applied pressure is applied. Can be eliminated. As a result, the present manufacturing method can prevent bubbles from remaining even when the rib precursor is filled under atmospheric pressure. In other words, it is not necessary to apply a reduced pressure when filling the rib precursor. Of course, the bubbles may be removed more easily by reducing the pressure.

  Subsequently, the rib precursor is cured. When the rib precursor 33 spread on the glass flat plate 31 is photocurable, as shown in FIG. 7B, the laminated body of the glass flat plate 31 and the mold 20 is used as a light irradiation device (not shown). Then, the rib precursor 33 is irradiated with light such as ultraviolet rays through the glass flat plate 31 and the mold 20 to be cured. In this manner, a molded body of the rib precursor, that is, the rib itself is obtained.

  Finally, the glass flat plate 31 and the molding die 20 are taken out from the light irradiation device while the obtained rib 32 is adhered to the glass flat plate 31, and the molding die 20 is peeled and removed as shown in FIG. Since the flexible mold 20 used here is excellent in handling properties, the mold 20 can be easily peeled and removed with a small force without damaging the rib 32 adhered to the glass flat plate 31. Of course, a large-scale apparatus is not necessary for this peeling and removing operation.

  Subsequently, the present invention will be described with reference to examples thereof. Needless to say, the present invention is not limited to these examples.

Example 1
In this example, in order to produce a PDP back plate having ribs (partitions) in a lattice pattern, a flexible mold having a lattice groove pattern as shown in FIGS. 3 and 4 is produced. did.

  For the production of a flexible mold, cells having dimensions of 700 μm long × 200 μm wide × 200 μm deep on each side of a brass plate 210 mm long × 300 mm wide × 20 mm thick, each having a vertical period of 800 μm and a total length of 180 Machined regularly with a transverse period of 270 μm and a transverse total of 840 pieces. The cell is for defining the discharge display cell of the PDP back plate obtained. A master mold having a lattice-like projection pattern on the surface was obtained. In this master mold, the protrusion pattern is composed of a vertical protrusion and a horizontal protrusion, each of which has an isosceles trapezoidal cross section, and is arranged substantially in parallel with each other at a predetermined interval.

  Using the master mold described above, a flexible mold was produced according to the technique described above with reference to FIG.

  First, in order to use for forming the shaping layer of a shaping | molding die, two types of ultraviolet curable resin compositions of the following compositions were prepared.

High viscosity ultraviolet curable resin composition (A):
Aliphatic urethane acrylate oligomer (trade name “Photomer 6010”, manufactured by Henkel) 80% by weight
1,6-hexanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) 20% by weight
2-Hydroxy-2-methyl-1-phenyl-propan-1-one (photopolymerization initiator, trade name “Darocur 1173”, manufactured by Ciba Specialty Chemicals) 1% by weight

Low viscosity UV curable resin composition (B):
Aliphatic urethane acrylate oligomer (trade name “Photomer 6010”, manufactured by Henkel) 40% by weight
1,6-hexanediol diacrylate (manufactured by Shin-Nakamura Chemical Co., Ltd.) 60% by weight
2-Hydroxy-2-methyl-1-phenyl-propan-1-one (photopolymerization initiator, trade name “Darocur 1173”, manufactured by Ciba Specialty Chemicals) 1% by weight

  When the viscosity of each resin composition was measured with a Brookfield (B) viscometer, the viscosity of the resin composition (A) was 8,500 cps, and the viscosity of the resin composition (B) was 110 cps ( Shaft # 5, 20 rpm, 22 ° C.).

  Further, a reinforced polypropylene (PP) film having a length of 300 mm, a width of 300 mm, and a thickness of 0.2 mm was prepared for use as a support for a mold. This reinforced PP film is reinforced with continuous fibers of E glass (aluminoborosilicate glass), and is available from Toyobo Co., Ltd. under the product name “Quick Form”. Is about 10 μm, and the content is about 50% in terms of volume fraction.

  Next, the UV curable resin composition (A) prepared as described above was applied to one side of the reinforced PP film with a thickness of about 200 μm, while UV was applied to the master-shaped protrusion pattern surface prepared in the previous step. The curable resin composition (B) was applied. Thereafter, the reinforced PP film and the master mold were laminated so that the respective resin coatings overlapped. The longitudinal direction of the reinforced PP film was set parallel to the longitudinal projections of the master mold, and the total thickness of the ultraviolet curable resin composition sandwiched between the reinforced PP film and the master mold was set to about 250 μm. When the reinforced PP film was carefully pressed using a laminating roll, the UV-curable resin composition was completely filled in the concave portion of the master mold, and no air bubbles were observed.

In this state, using a fluorescent lamp manufactured by Mitsubishi Electric OSRAM Co., Ltd., ultraviolet light having a wavelength (peak wavelength: 352 nm) at 300 to 400 nm is applied to the ultraviolet curable resin composition layer through the reinforced PP film for 30 seconds. Irradiated. The irradiation amount of ultraviolet light was 200 to 300 mJ / cm ² . Two types of ultraviolet curable resin compositions were cured, and a shaping layer was obtained. Subsequently, when the reinforced PP film was peeled from the master mold together with the shaping layer, a flexible mold having a grid-like groove pattern having a shape and dimensions corresponding to the master-like grid-like projection pattern was obtained. It was. The thickness of this flexible mold was about 450 μm.

Example 2
In this example, using the flexible mold produced in Example 1, a back plate for PDP (a fine structure referred to in the present invention) is produced according to the method described above with reference to FIG. did.

  The flexible mold was positioned and placed on the glass substrate for PDP. The groove pattern of the mold was made to face the glass substrate. Next, a photosensitive ceramic paste was filled in a thickness of 110 μm between the mold and the glass substrate. The ceramic paste used here had the following composition.

Photocurable oligomer: 21.0 g of bisphenol A diglycidyl methacrylate acid adduct (manufactured by Kyoeisha Chemical Co., Ltd.)
Photocurable monomer: Triethylene glycol dimethacrylate (manufactured by Wako Pure Chemical Industries, Ltd.) 9.0 g
Diluent: 1,3-butanediol (manufactured by Wako Pure Chemical Industries) 30.0 g
Photopolymerization initiator: bis (2,4,6-trimethylbenzoyl) -phenylphosphine oxide (trade name “Irgacure 819”, manufactured by Ciba Specialty Chemicals) 0.3 g
Surfactant: POCA (phosphate propoxyalkyl polyol, manufactured by 3M) 1.5 g
1.5 g of sulfonic acid surfactant (trade name “Neopelex Nо.25”, manufactured by Kao Corporation)
Inorganic particles: Mixed powder of lead glass and ceramic (trade name “RFW-030”, manufactured by Asahi Glass Co., Ltd.) 270.0 g

  When the viscosity of this ceramic paste was measured with a Brookfield (B) viscometer, it was 7,300 cps (shaft # 5, 20 rpm, 22 ° C.).

  After the ceramic paste was applied on the entire surface of the glass substrate, the mold was laminated so as to cover the surface of the glass substrate. When a molding die was carefully pressed using a rubber laminate roll having a diameter of 200 mm and a weight of 30 kg, the groove of the molding die was completely filled with the ceramic paste.

In this state, using a fluorescent lamp manufactured by Philips, blue light having a wavelength of 400 to 500 nm (peak wavelength: 450 nm) was irradiated from both sides of the mold and the glass substrate for 30 seconds. The irradiation amount of ultraviolet light was 200 to 300 mJ / cm ² . The ceramic paste hardened and became ribs. Subsequently, when the glass substrate was peeled from the mold together with the ribs thereon, a glass substrate with grid-like ribs was obtained. In the obtained glass substrate, the shape and dimensions of the ribs exactly matched that of the groove of the master mold used for the production of the flexible mold. Finally, the glass substrate was baked at 550 ° C. for 1 hour to burn and remove organic components in the paste. A back plate for PDP provided with lattice-like ribs composed only of glass components was obtained. When the rib defects were inspected with an optical microscope, no defects such as rib defects were found.

Test example 1
Measurement of dimensional change of composite film In this example, the dimensions when the relative humidity at 22 ° C. was changed from 85% RH to 55% RH for the composite film used as the support in the flexible mold of the present invention. The change was measured by the following procedure.

1. Preparation of Test Composite Film The reinforced PP film (length 300 mm × width 300 mm × thickness 0.2 mm) used as the support for the flexible mold in Example 1 was used as the test composite film.

2. Marking for Dimension Measurement As shown in FIG. 8, marking for dimension measurement was given to four corners (four points A, B, C and D, distance between points: 250 mm) of the test composite film 21.

3. Constant Temperature Humidity Storage The test composite film of Step 2 was placed in a constant temperature and humidity oven of 22 ° C./55% RH and stored for one week.

4). Measurement of XY coordinates The test composite film of step 3 was taken out of the oven, and the XY coordinates of four points immediately thereafter (four points A, B, C, and D) were measured on a measuring machine. At the time of measurement, it was 22 ° C./55% RH. The measurement results described as “Data 1” in Table 1 below were obtained.

5). Constant humidity storage The test composite film of step 2 was placed in a constant temperature and humidity oven of 22 ° C./85% RH and stored for one week.

6). Measurement of XY coordinates The test composite film of step 5 was taken out of the oven, and the XY coordinates of four points immediately thereafter (four points A, B, C, and D) were measured on a measuring machine. At the time of measurement, it was 22 ° C./55% RH. The measurement results described as “Data 2” in Table 1 below were obtained.

7). Measurement of dimensional change When the measurement results (dimensions between points) obtained in steps 4 and 6 were compared, it was confirmed that there was a dimensional change described as "Difference" in Table 1 below.

  Moreover, when the hygroscopic expansion coefficient between each point was also calculated, the result described in Table 1 below was obtained.

  As understood from the results in Table 1 above, the composite film subjected to the test in this example did not show a significant dimensional change with respect to a change in the relative humidity of 30 RH%.

Test example 2
Measurement of dimensional change of flexible mold In this example, the dimensional change of the flexible mold of the present invention when the relative humidity at 22 ° C. is changed from 85% RH to 55% RH is as follows. It was measured.

1. Production of a flexible mold The flexible mold described in Example 1 was produced under the same production conditions. A flexible molding die having a thickness of 450 μm, comprising a support made of a reinforced PP film and a shaping layer made of a cured product derived from urethane acrylate and an acrylic monomer (Tg: −40 ° C.) laminated thereon. It was.

2. Marking for dimension measurement In the same manner as in Test Example 1, marking for dimension measurement was given to four corners of the test mold (four points A, B, C and D, distance between points: 250 mm). .

3. Constant Temperature Humidity Storage The test mold of Step 2 was placed in a constant temperature and humidity oven of 22 ° C./55% RH and stored for one week.

4). Measurement of XY coordinates The test mold of Step 3 was taken out of the oven, and the XY coordinates of the four points immediately thereafter (four points A, B, C, and D) were measured on a measuring machine. At the time of measurement, it was 22 ° C./55% RH. The measurement results described as “Data 3” in Table 2 below were obtained.

5). Constant Temperature Humidity Storage The test mold of Step 2 was placed in a constant temperature and humidity oven of 22 ° C./85% RH and stored for one week.

6). Measurement of XY coordinates The test mold in Step 5 was taken out of the oven, and the XY coordinates at the four points immediately thereafter (four points A, B, C, and D) were measured on a measuring machine. At the time of measurement, it was 22 ° C./55% RH. The measurement results described as “Data 4” in Table 1 below were obtained.

7). Measurement of dimensional change When the measurement results (dimensions between points) obtained in steps 4 and 6 were compared, it was confirmed that there was a dimensional change described as "Difference" in Table 2 below.

  Moreover, when the hygroscopic expansion coefficient between each point was also calculated, the result described in the following Table 2 was obtained.

  As understood from the results in Table 2 above, the flexible mold subjected to the test in this example did not show a significant dimensional change with respect to a change in the relative humidity of 30 RH%.

Comparative Test Example 1
Although the method described in Test Example 1 was repeated, in this example, for comparison, an epoxy glass composite film (manufactured by Arisawa Seisakusho) was used as a test composite film (reinforced polymer film) instead of PP. And the size of the test composite film was changed to length 300 mm × width 300 mm × thickness 0.25 mm.

  When the dimensional change of the composite film was measured according to the method described in Test Example 1, the results described in Table 3 below were obtained. In the table, “Data 5” is the result when stored in a constant temperature and humidity oven of 22 ° C./55% RH for one week, and “Data 6” is the constant temperature and humidity of 22 ° C./85% RH. It is the result when stored in an oven for one week.

  As understood from the results in Table 3 above, the composite film subjected to the test in this example exhibits a hygroscopic expansion coefficient of about 8 ppm / RH%, and exhibits a significant dimensional change with respect to a change in relative humidity of 30 RH%. Indicated.

Comparative test example 2
The procedure described in Test Example 2 was repeated. In this example, for comparison, in the reinforced polymer film used as the support of the flexible mold, an epoxy resin was used instead of PP, and the reinforced polymer was used. The size of the film was changed to length 300 mm × width 300 mm × thickness 0.25 mm.

  When the dimensional change of the flexible mold was measured according to the method described in Test Example 2, the results shown in Table 4 below were obtained. In the table, “Data 7” is the result when stored in a constant temperature and humidity oven of 22 ° C./55% RH for one week, and “Data 8” is the constant temperature and humidity of 22 ° C./85% RH. It is the result when stored in an oven for one week.

  As understood from the results of Table 4 above, the flexible mold subjected to the test in this example shows a hygroscopic expansion coefficient of about 8 ppm / RH%, which is significant for a change in relative humidity of 30 RH%. The dimensional change was shown.

Comparative test example 3
Although the method described in Test Example 2 was repeated, in this example, a polyethylene terephthalate (PET) film having a thickness of 188 μm was used as a support instead of the reinforced PP film in the production of a flexible mold for comparison. Used as. The size of the PET film was 300 mm long × 300 mm wide × 0.2 mm thick.

  When the dimensional change of the flexible mold was measured according to the method described in Test Example 2, it showed a hygroscopic expansion coefficient of about 8 ppm / RH%, and showed a significant dimensional change with respect to a change of 30 RH% relative humidity. It has been found. The PET film used as the support also showed a hygroscopic expansion coefficient of about 8 ppm / RH%.

1 Master mold 2 Silicone rubber 3 UV curable molding material (pre-shaped layer)
4 Projection Pattern 10 Transfer Mold 11 Base 12 Transfer Pattern Layer 14 Projection Pattern 20 Flexible Mold 21 Support 22 Forming Layer 30 Microstructure 31 Glass Flat Plate 32 Rib

Claims (17)

A flexible mold used to transfer a microstructure pattern in the manufacture of a microstructure,
(1) a support made of a composite material of a polymer material and a reinforcing material;
(2) a shaping layer supported by the support and having a microstructured surface on the surface;
A flexible mold for transferring a fine pattern, characterized by comprising:   The flexible mold according to claim 1, wherein the microstructure surface includes a groove pattern.   The flexible mold according to claim 1, wherein the microstructure surface includes a protrusion pattern.   The flexible molding die according to any one of claims 1 to 3, wherein the reinforcing material is made of an inorganic material, an organic material, a metal material, a metal oxide, or a mixture thereof.   The flexible mold according to claim 4, wherein the reinforcing material is a fiber.   The flexible molding die according to any one of claims 1 to 5, wherein the reinforcing material is contained in a range of 20 to 70% by volume based on the total amount of the composite material.   2. The polymer material is one member selected from the group consisting of polyolefin, polyvinyl chloride, polystyrene, polycarbonate, polyethylene terephthalate, polybutylene terephthalate, polyether sulfone, polyphenylene sulfide, and liquid crystal polymer. The flexible shaping | molding die of any one of -6.   The flexible mold according to claim 7, wherein the polyolefin is polypropylene or cycloolefin.   The flexible mold according to claim 1, wherein the support is made of a composite material of polypropylene and glass fiber.   The flexible mold according to any one of claims 1 to 9, wherein the shaping layer comprises a cured product of a curable resin composition.   The flexible mold according to claim 10, wherein the curable resin composition is a photocurable resin composition.   The flexible mold according to any one of claims 1 to 11, wherein the fine structure pattern of the fine structure is a protrusion pattern corresponding to a rib of a back plate for a plasma display panel. It is a method of manufacturing the flexible shaping | molding die of any one of Claims 1-11, Comprising: The following processes:
Preparing a master mold having a projection pattern on the surface thereof having a shape and dimensions corresponding to the microstructure pattern of the microstructure;
Applying a curable resin composition at a predetermined film thickness to the master-shaped pattern forming surface to form a pre-shaped layer;
A step of further laminating a film-like support composed of a composite material of a polymer material and a reinforcing material on the pre-shaped layer to form a laminate including the master mold, the pre-shaped layer and the support;
A step of curing the curable resin composition of the pre-shaped layer, and releasing the shaped layer formed by curing of the curable resin composition together with the support from the master mold, and a support, Producing a flexible mold having a shaping layer with a groove pattern having a shape and a dimension corresponding to the microstructure pattern, the back surface of which is supported by the support;
The manufacturing method of the flexible shaping | molding die characterized by comprising.   The method for producing a flexible mold according to claim 13, wherein a film-like support having a primer layer on the pre-shaped layer side is used. A flexible mold used to transfer a microstructure pattern in the manufacture of a microstructure,
A mold for fine pattern transfer, which has a hygroscopic expansion coefficient of less than 5 ppm / RH%.   The mold for transferring a fine pattern according to claim 15, wherein the hygroscopic expansion coefficient is 3 ppm / RH% or less.   The mold for transferring a fine pattern according to claim 15, wherein the hygroscopic expansion coefficient is 1 ppm / RH% or less.

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