TW201831317A - Rough-faced sheet and manufacturing method of resin original plate for printing using the same, manufacturing method of flexographic printing plate, and manufacturing method of liquid crystal display element which is improved in productivity by using a flexographic printing plate and low in cost - Google Patents

Abstract

This invention provides a rough-faced sheet without fisheyes and the use thereof. Further, method for producing a liquid crystal display element which is improved in productivity by using a flexographic printing plate and low in cost is provided. The rough-faced sheet (1) comprises a surface layer (5) including an adhesive resin (3) and fine particles (4), and at least a portion of the fine particles (4) protrudes, thereby forming a surface of the surface layer (5) made into a rough-faced mold surface (6). Methods of manufacturing a resin original plate for printing and a flexographic printing plate comprises a step of curing the layer of the photosensitive resin composition under the condition of being contacted with the mold surface by irradiation with active light rays, and then perform peeling. A method of manufacturing a liquid crystal display element comprising a step of forming a liquid crystal alignment film by flexographic printing using the flexographic printing plate.

Description

Roughened sheet, method for producing printing resin master using the same, method for producing flexographic printing plate, and method for producing liquid crystal display device

The present invention relates to a roughened sheet used for the production of a printing resin original which is the basis of a flexographic printing plate, a method for producing a printing resin original using the roughened sheet, and a flexographic printing plate. Manufacturing method and method of manufacturing liquid crystal display element.

In the electrode formation surface of the substrate constituting the liquid crystal display element, a flexographic printing method having excellent printing characteristics is used in order to form a liquid crystal alignment film having a thickness as high as possible and requiring a high coating film quality without pinholes or the like. In the flexographic printing method, a flexographic printing plate is used which comprises a soft resin sheet (printing resin original), and the surface of the sheet is formed into a plate surface, that is, a state in which an ink serving as a base of a liquid crystal alignment film or the like is carried. The lower surface is brought into contact with the surface to be printed such as the electrode forming surface to form a surface for transferring the ink to the surface to be printed.

In order to improve the wettability to the ink and to maintain the ink well, and the held ink can be favorably transferred to the surface to be printed, the surface of the flexographic printing plate is usually made into a rough surface having a predetermined surface roughness. In the method for producing a printing resin original plate described in Patent Document 1, first, a photosensitive resin composition which is a basis of a resin sheet is applied in a layered manner to a surface which is roughened to a roughened surface. On the sheet, in this state, it is hardened by irradiation with active light such as ultraviolet rays. Then, since the sheet formed by hardening is peeled off from the roughened sheet, the surface of the sheet which is in contact with the mold surface is transferred with a rough surface shape, thereby forming the surface into a roughened surface.

According to the above production method, the printing resin original plate on which the entire surface of the plate surface is roughened can be produced with good productivity and at low cost. As a roughened sheet, as described in Patent Document 1, a sheet comprising a thermoplastic elastomer (Thermo Plastics Elastomer, TPE) such as an urethane-based elastomer is laminated and laminated on the opposite side of the die side. For example, a polyethylene terephthalate (PET) film or the like is used as a reinforcing film.

The roughened sheet is produced, for example, by extrusion molding a TPE into a sheet shape, and continuously inserting it into the outer peripheral surface together with the reinforcing film to form a rough surface shape corresponding to the surface of the roughened sheet. The rough surface of the rough surface of the original surface of the rough surface roller, and the pair of rollers. That is, the sheet of the TPE and the reinforcing film are laminated to each other by the pressure at the time of insertion, and the rough surface shape of the original mold surface is transferred on the surface of the sheet to form the surface into a roughened surface. . The roughened sheet to be produced is cut into a predetermined size or the like and used for the production of a resin original for printing.

The reason why the TPE is used is that the rough surface shape of the outer peripheral surface of the roughened roll, that is, the original mold face, can be transferred to the die face relatively efficiently by the above-described manufacturing method. Further, the reason is that since the affinity and wettability of the TPE and the photosensitive resin composition are high, the rough surface shape of the mold surface can be favorably transferred to the surface of the printing resin original plate. However, in the conventional roughened sheet, when a TPE is synthesized, a partial gel called a fisheye is easily generated, and if the resulting fisheye is sandwiched between the reinforcing film, it is easy. A local protrusion that is larger than the unevenness forming the rough surface is generated on the die face. Further, when a printing resin original plate is produced by using a roughened sheet having projections, the flatness of the surface of the plate is damaged by the depression of the projection on the surface of the plate, and as a result, the uniformity of the thickness of the liquid crystal alignment film or the like is impaired. Question.

In terms of the synthesis mechanism of the TPE, it is difficult to completely remove the fisheye, and after lamination, a large amount of fish eyes must be contained on the roughened sheet before cutting. Therefore, when manufacturing a roughened sheet, it is necessary to select and cut out a region where no fish eyes are generated after confirming the position where the fish eye is generated, and waste of material becomes large.

In addition, the part of the gel forming the fish eye is substantially the same as the TPE, and the color or the appearance is almost the same. Therefore, it is necessary to check the position at the time of cutting out or to check the roughened sheet after cutting. Labor and time. Therefore, in combination with these cases, in the conventional manufacturing method, there is a problem that the productivity of the roughened sheet is low.

Further, when a roughened sheet which is exposed to fish eyes during inspection is used for the production of the resin original for printing, a defect is formed on the surface of the plate to cause a defective product which cannot be used for printing. Further, there is a case where the defective ratio of the resin original plate for printing and the flexographic printing plate is increased, the productivity is lowered, and the productivity of the liquid crystal display element is finally lowered. [Prior Art Document] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2013-119179

[Problems to be Solved by the Invention] An object of the present invention is to provide a roughened sheet material without fish eyes, and a method for producing a printing product by suppressing the occurrence of defects by using the roughened sheet material. A method of producing a resin original and a flexographic printing plate. Further, an object of the present invention is to provide a production method for producing a liquid crystal display element which is further improved in productivity and cost-effectively using the flexographic printing plate produced. [Technical means to solve the problem]

The present invention is a roughened sheet for use in the production of a resin original for printing, and includes at least a surface layer on which a surface is made into a roughened surface, and a reinforcing film provided on the back side of the surface layer. The surface layer includes a binder resin, and fine particles dispersed in the binder resin, and at least a portion of the fine particles protrude from a surface of the surface layer, so that the surface is made into a roughened mold. surface.

Moreover, the present invention is a method for producing a resin original plate for printing, which comprises the steps of: bringing a layer of a photosensitive resin composition into contact with the die face of the roughened sheet; The layer is cured by irradiation with active light and then peeled off from the die face, thereby transferring the rough surface shape of the die face on the surface of the layer in contact with the die face, thereby The surface is made into a roughened surface. Further, the present invention is a method of producing a flexographic printing plate comprising thermally cutting a corresponding portion of a printing resin original plate manufactured by the manufacturing method to form a pinching portion for mounting on a printing machine, and a chuck hole A step of.

Further, the present invention is a method of producing a liquid crystal display element comprising the steps of forming a liquid crystal alignment film by flexographic printing using a flexographic printing plate manufactured by the above-described manufacturing method. [Effects of the Invention]

According to the present invention, it is possible to provide a roughened sheet free of fish eyes and a method for suppressing occurrence of defects by using the roughened sheet, thereby producing a printing resin original plate with good productivity, and flexographic printing. The manufacturing method of the edition. Further, according to the present invention, it is possible to provide a manufacturing method for producing a liquid crystal display element which is further improved in productivity and cost-effectively using the flexographic printing plate produced.

<Roughened Sheet> FIG. 1 is a cross-sectional view showing an enlarged layer structure of an example of the roughened sheet of the present invention. Referring to Fig. 1, the roughened sheet 1 of this example includes a PET film as the reinforcing film 2 and a surface layer 5 laminated on one surface (upper surface in the drawing) of the reinforcing film 2.

The surface layer 5 contains the binder resin 3 and the fine particles 4 dispersed in the binder resin 3, and at least a part of the fine particles 4 protrudes from the surface of the surface layer 5, so that the surface is made into a roughened mold surface 6 . In the case of the example in the figure, the surface of the protruding fine particles 4 is covered with an extremely thin film containing the binder resin 3. However, the surface of the fine particles 4 may be exposed without being covered by the film, or may be mixed with the coated person and the exposed person.

The surface layer 5 can be formed, for example, by applying a coating agent containing the binder resin 3 and the fine particles 4 to one surface of the reinforcing film 2, and then drying the coating agent, and further using ultraviolet rays when the binder resin 3 has curability. The binder resin 3 is hardened by irradiation or heating of the active light. Therefore, the step of forming the die face using the roughened roll and the surface layer containing TPE or the like suitable for this can be omitted.

Therefore, as the binder resin 3, various materials other than TPE which do not cause fisheye problems can be used, and various defects caused by fish eyes can be suppressed. The roughened sheet 1 is produced, for example, in such a manner that the surface layer 5 is continuously formed by continuously applying a coating agent on one side thereof while continuously conveying the long reinforcing film 2 . In addition, the roughened sheet 1 to be produced is cut into a predetermined length, a predetermined width, and the like as needed, and is used for the production of a resin original for printing.

In the step of forming a mold surface using a roughened roll, in the case of changing or adjusting the line thickness or the three-dimensional shape of the mold surface, it is necessary to separately prepare a dedicated rough surface roll for different mold faces, and there is a need to separately prepare a special rough surface roll for the different mold faces. The problem of high manufacturing cost of roughened sheets and flexographic printing plates. In the case of the surface layer 5 including the binder resin 3 and the fine particles 4, the surface layer 5 can be arbitrarily changed and adjusted by adjusting the type, the particle diameter, the blending ratio, the coating thickness of the coating agent, and the like of the fine particles 4. The line surface of the surface of the mold surface 6 is thick or three-dimensional.

Further, the roughened sheet 1 having the surface of the surface layer 5 on the surface of the surface layer 5 is more easily obtained from the results of the examples and the comparative examples described later than the roughened sheet having the conventional mold surface containing TPE. The formed printing resin original plate is peeled off. Therefore, in combination with these circumstances, the roughened sheet 1 or the flexographic printing plate can be produced with good productivity and at low cost.

As the binder resin 3 forming the surface layer 5, for example, various resins which are transparent to active light for producing a resin original for printing can be used. Examples of the binder resin 3 include one or two or more of an acrylic resin, a polycarbonate, a polyvinyl chloride, a polystyrene, a polyester, and a polyurethane. In particular, a thermoplastic resin, a two-liquid curable property, an active light curable property, or a thermosetting acrylic resin is preferable, and among them, an acrylic polyurethane 2-liquid-curing acrylic resin is preferable. Examples of the acrylic polyurethane 2-liquid-curing acrylic resin include a main component containing an acrylic polyol and a curing agent containing an isocyanate.

In general, since the acrylic resin has high affinity or wettability with the photosensitive resin composition which is the basis of the original resin for printing, the rough surface shape of the mold surface can be favorably transferred to the surface of the printing resin original plate. As the fine particles 4, particles of a resin, particles of an inorganic material, or the like can be used. Examples of the particles of the resin include particles of an acrylic resin, an anthrone resin, polystyrene, and polycarbonate. Examples of the particles of the inorganic material include particles of glass, titanium oxide, barium sulfate, talc, clay, alumina, calcium carbonate, and cerium oxide. One or two or more of these particles may be used as the fine particles 4.

Among them, fine particles 4 containing a material which is transparent to active light for producing a resin original for printing is preferable. In addition, in FIG. 1, the three-dimensional shape of the fine particles 4 is simply a spherical shape, but the three-dimensional shape of the fine particles 4 is not limited to a spherical shape, and various three-dimensional shapes such as an amorphous granular shape or an arbitrary polyhedral shape may be used. .

For example, when an acrylic urethane 2-liquid-curing acrylic resin is used as the binder resin 3, the main component, the curing agent, and the fine particles 4, which are the basis thereof, are blended in a predetermined ratio, and further, if necessary A coating agent is prepared by adding a solvent or the like for adjusting the viscosity. In addition to the function of enhancing the tensile strength of the entire roughened sheet 1 as a literal surface, the reinforcing film 2 also functions to correct the following: the roughened sheet 1 is an activator-curable adhesive. The resin 3 is warped by shrinkage or the like at the time of curing.

As the reinforcing film 2, a PET film can be preferably used as described. The PET film is excellent as a function of the reinforcing film 2 and the like. In particular, a PET film which is transparent to active light for producing a resin original for printing is preferable. Among them, as the reinforcing film 2, for example, a film of polyvinyl alcohol (PVA), polyamine, polyimide (PI), polycarbonate, cellulose acetate or the like can be used.

On one surface (upper surface in the drawing) of the laminated surface layer 5 of the reinforcing film 2, a primer treatment may be performed in order to improve the adhesion of the surface layer 5 as needed. Examples of the primer treatment include one or two or more kinds of corona discharge treatment, flame treatment, ozone treatment, ultraviolet irradiation treatment, sand blast treatment, and solvent treatment. Further, for example, a primer layer containing various materials having excellent affinity and adhesion to the PET forming the reinforcing film 2 or the adhesive resin 3 forming the surface 5 may be formed.

The fine particles 4 forming the surface layer 5 preferably have a minimum particle size distribution (particle size distribution) of 2.0 μm or more and a maximum particle size distribution of 30.0 μm or less. The minimum value and the maximum value of the particle size distribution are the minimum value and the maximum value of the particle diameter in the measurement results of the particle size distribution obtained for the fine particles 4 of the measurement object.

When the minimum value of the particle size distribution of the fine particles 4 is less than 2.0 μm, the fine particles 4 include particles which are too small for making the surface of the surface of the flexographic printing plate into a rough surface which can maintain a sufficient thickness of the ink. On the other hand, in the case where the maximum value of the particle size distribution of the fine particles 4 exceeds 30.0 μm, the fine particles 4 contain an excessively large particle size for a rough surface in which the surface of the plate is made to maintain a sufficient thickness of the ink. particle of.

Therefore, there is a concern that, depending on the coating thickness of the coating agent or the blending ratio of the binder resin 3 and the fine particles 4, the flexographic printing plate produced using the roughened sheet 1 cannot be used in either case. The entire surface of the surface of the plate is formed to have a non-uniform rough surface shape in which the ink of a sufficient thickness can be uniformly maintained. Further, there is a case where, for example, the thickness of the liquid crystal alignment film formed by the flexographic printing method is insufficient or the thickness becomes uneven.

On the other hand, when the minimum value and the maximum value of the particle size distribution of the fine particles 4 are each in the above range, particles having an excessively small particle diameter or particles having an excessively large particle diameter can be removed. Therefore, the mold surface 6 of the roughened sheet 1 and the entire surface of the surface of the flexographic printing plate can be made into a rough surface having an unevenness of an appropriate size. Further, for example, a liquid crystal alignment film formed using the flexographic printing plate and formed by a flexographic printing method may be made uniform and have a sufficient thickness.

Further, the fine particles 4 are preferably obtained from the standard deviation σ and the average particle diameter of the particle diameter distribution by the formula (1): coefficient of variation Cv = (standard deviation σ) / (average particle diameter) (1), and The coefficient of variation Cv of the deviation of the particle size distribution is 0.35 or less. When the coefficient of variation Cv exceeds 0.35, the variation in the particle size distribution becomes large, and the fine particles 4 contain a large amount of the particles having an excessively small particle diameter or particles having an excessively large particle diameter.

Therefore, there is a concern that although the coating thickness of the coating agent, the blending ratio of the binder resin 3 and the fine particles 4, and the like are still used, the surface of the flexographic printing plate produced by using the roughened sheet 1 cannot be used. The entire surface is formed into a rough surface shape which can uniformly maintain a sufficient thickness of the ink. Further, there is a case where, for example, the thickness of the liquid crystal alignment film formed by the flexographic printing method is insufficient or becomes uneven.

On the other hand, by setting the coefficient of variation Cv to the above range, particles having an excessively small particle diameter and particles having an excessively large particle diameter can be removed. Therefore, the mold surface 6 of the roughened sheet 1 and the entire surface of the surface of the flexographic printing plate can be made into a rough surface having an unevenness of an appropriate size. Further, for example, a liquid crystal alignment film formed using the flexographic printing plate and formed by a flexographic printing method may be made uniform and have a sufficient thickness.

Further, in consideration of further improving these effects, the coefficient of variation Cv is preferably 0.25 or less of the above range. However, when the coefficient of variation Cv is too small, the particle diameter is nearly monodispersed, so that the pitch of the unevenness formed on the die face 6 of the roughened sheet 1 and the surface of the flexographic printing plate is close to a single one. In this case, although the range of the pitch itself is different, it is still a single pitch, and exists in the electrode due to the interaction with the electrode forming surface of the substrate including the liquid crystal display element including the portion in which the unevenness is formed. A case where moire stripes are formed in the liquid crystal alignment film formed on the surface.

Therefore, in consideration of suppressing the generation of moire fringes, the coefficient of variation Cv is preferably 0.15 or more in the above range, and preferably 0.18 or more, and particularly preferably 0.20 or more. Further, in this case, it is preferable that the minimum value of the particle diameter distribution of the fine particles 4 is 2.0 μm or more, and the maximum value of the particle diameter distribution is 30.0 μm or less. The reason is as explained before. Further, in order to suppress the generation of the moire fringes, as the fine particles 4, mixed particles of two kinds of fine particles having different particle diameter distributions may be used in combination.

When mixed particles of two kinds of fine particles having different particle diameter distributions are used, it is possible to suppress the pitch of the unevenness formed on the surface of the mold surface 6 of the roughened sheet 1 and the surface of the flexographic printing plate from being single. Therefore, for example, it is possible to suppress the occurrence of moire fringes in the liquid crystal alignment film formed on the electrode formation surface due to the interaction with the electrode formation surface of the substrate constituting the liquid crystal display element. However, when the variation in the particle size distribution of the entire mixed particles is large, the fine particles 4 still contain a large number of particles having an excessively small particle diameter or particles having an excessively large particle diameter. Therefore, the coefficient of variation Cv of the entire mixed particles is still preferably 0.35 or less.

By setting the coefficient of variation Cv to the above range, particles having an excessively small particle diameter and particles having an excessively large particle diameter can be removed. Therefore, the mold surface 6 of the roughened sheet 1 and the entire surface of the surface of the flexographic printing plate can be made into a rough surface having an unevenness of an appropriate size. Further, for example, a liquid crystal alignment film formed using the flexographic printing plate and formed by a flexographic printing method may be made uniform and have a sufficient thickness.

However, when the coefficient of variation Cv is too small, the particle diameters of the two kinds of fine particles are close to each other, and the particle diameter of the entire mixed particles is close to monodisperse, and on the contrary, there is a tendency that moiré is likely to occur. When the generation of the moire fringes is suppressed, the coefficient of variation Cv of the entire mixed particles is preferably 0.15 or more in the above range, and preferably 0.18 or more, and particularly preferably 0.20 or more. The range of the particle size distribution of the two kinds of fine particles constituting the mixed particles can be arbitrarily set. The range of the particle size distribution of the two kinds of fine particles may be different from each other or may be partially repeated.

Among them, both of the fine particles have a minimum particle size distribution of 2.0 μm or more and a maximum particle size distribution of 30.0 μm or less. Thereby, the particles having an excessively small particle diameter and the particles having an excessively large particle diameter can be removed, and the surface of the plate of the flexographic printing plate produced by using the roughened sheet 1 can be formed so as to uniformly maintain the ink of a sufficient thickness without unevenness. Rough surface. Further, for the same reason, the coefficient of variation Cv of each of the two kinds of fine particles is preferably 0.35 or less.

However, as described above, by using two kinds of fine particles in combination, it is possible to suppress the particle size distribution of the entire mixed particles from being monodispersed, and therefore the coefficient of variation Cv of at least one of the two kinds of fine particles may be lower than the 0.15. The above range. The blending ratio of the two types of fine particles can be set to an arbitrary range depending on the range of the particle size distribution of each fine particle, the coefficient of variation Cv, or the coefficient of variation Cv of the entire mixed particle. However, in order to further improve the effect of using the mixed particles, it is preferable to set the ratio of the fine particles having a small particle size distribution to the total amount of the mixed particles to 10% by mass or more, and particularly preferably to 60% by mass. The above is 90% by mass or less.

Further, in the present invention, the particle size distribution of the fine particles 4 or the fine particles constituting the mixed particles is expressed by a volume distribution measured by a laser diffraction/scattering method based on the Mie scattering theory. The standard deviation σ which is the basis of the coefficient of variation Cv is obtained by assuming that the shape of the particle is assumed to be spherical and converted based on the number. The average particle diameter is an arithmetic mean diameter based on the number of particles obtained by dividing the shape of the particles into a spherical shape and integrating them based on the number of particles, and dividing the number of particles. In the examples, the volume distribution of the fine particles was measured using a laser diffraction/scattering type particle size distribution measuring apparatus LA-950V2 manufactured by Horiba, Ltd., but the measuring apparatus is not limited thereto.

The blending ratio of the binder resin 3 and the fine particles 4 can be arbitrarily adjusted according to the size of the unevenness formed in the die face 6, and the like. However, when the binder resin 3 is too small, there is a concern that a continuous strong surface layer 5 cannot be formed. Conversely, when the binder resin 3 is excessive, there is a bump formed in the mold surface 6 which is the surface of the surface layer 5. Too little worry.

In the surface layer 5 to be formed, it is preferable that the surface layer 5 is formed in a state in which fine particles are buried in a ratio of 1/2 to 1/8 in terms of volume on the binder resin 3. Therefore, the blending ratio of the two is expressed by the volume ratio of the binder resin 3 to the total amount of the fine particles 4 in the binder resin 3 (solid content of the resin obtained by removing the volatile component), and is preferably set to 30. 5% by volume or more and 80% by volume or less.

The thickness of the surface layer 5, that is, the thickness from the single surface of the self-reinforced film 2 to the tip end of the convex portion in the unevenness of the mold surface 6 formed of the fine particles 4 can be arbitrarily set based on the particle diameter of the fine particles 4. For example, when the particle diameter of the fine particles 4 is in the range of 2.0 μm or more and 30.0 μm or less, the thickness of the surface layer 5 is not limited thereto, but is preferably 0.005 mm (= 5.0 μm) or more, and preferably 0.035. Mm (= 35.0 μm) or less.

The thickness of the reinforcing film 2 is preferably 0.050 mm or more, preferably 0.075 mm or more, and preferably 0.300 mm or less, and preferably 0.250 mm or less. When the thickness is less than the above range, for example, the roughened sheet 1 before cutting is wound into a roll, and the cut roughened sheet 1 is used for the production of the resin original for printing. The roughened sheet 1 is easily broken when the winding treatment is performed or the like. Further, when the roughened sheet 1 is broken, the fracture surface is formed in the rough surface shape of the surface of the mold surface 6 and the surface of the flexographic printing plate, and there is a concern that, for example, the thickness cannot be uniformly formed continuously. Liquid crystal alignment film.

On the other hand, when the thickness of the reinforcing film 2 exceeds the above range, the weight of the roughened sheet 1 is increased, and it is difficult to bend and roughen the roughened sheet 1, and thus the handleability and the like are lowered. Worry. Further, as the thickness of the reinforcing film 2 increases, the unevenness of the thickness of the reinforcing film 2 also increases, so that the coating thickness of the coating agent is likely to be uneven. Further, in the portion where the thickness of the PET film is small, there is a fear that the thickness of the binder resin is increased, and the fine particles are buried in the binder resin, and a region having a sufficiently rough surface cannot be formed as compared with the surroundings. In other words, there is a concern that unevenness is likely to occur in the distribution of the unevenness of the mold surface 6 as the surface of the surface layer 5, and further, the rough surface shape.

On the other hand, when the thickness of the reinforcing film 2 is in the above range, the occurrence of breakage or the like can be suppressed as much as possible, and the handleability of the roughened sheet 1 can be improved, and the uneven surface can be unevenly distributed without unevenness. The rough surface shape of 6 is uniformized. Further, in consideration of further uniformizing the rough surface shape of the die face 6, it is preferable that the thickness of the reinforcing film 2 is smaller in the above range. That is, the smaller the thickness of the reinforcing film 2 is, the smaller the thickness of the reinforcing film 2 is, and the coating thickness of the coating agent which is the basis of the surface layer 5 can be made uniform, and the rough surface shape can be made uniform.

In particular, in the case of combining with the fine particles 4 having a particle diameter of 2.0 μm or more and 30.0 μm or less, the thickness of the reinforcing film 2 is preferably 0.200 mm or less in the above range, and preferably 0.150 mm or less. It is especially preferably 0.100 mm or less. Thereby, the effect of making the rough surface shape uniform can be further improved. In addition, the thickness of the reinforcement film 2 is preferably 0.100 mm or more in consideration of prevention of breakage defects and the like.

Further, in the case where the primer layer is formed on one side of the reinforcing film 2 as a primer, in the present invention, the thickness of the reinforcing film 2 is set to a total thickness of the reinforcing film 2 and the primer layer. The thickness of the roughened sheet 1 which is the total thickness of the reinforcing film 2 and the thickness of the surface layer 5 is preferably 0.065 mm or more, and preferably 0.080 mm or more, in consideration of suppressing occurrence of breakage as much as possible. It is particularly preferably 0.120 mm or more. In addition, in consideration of improving the handleability of the roughened sheet 1, etc., the overall thickness is preferably 0.320 mm or less, preferably 0.285 mm or less, particularly preferably 0.230 mm or less, and further preferably 0.175 mm or less.

<Manufacturing Method of Printing Resin Original and Flexographic Printing Plate> FIGS. 2( a ) to 2 ( c ) are examples showing the procedure of a method for producing a resin plate for printing using the roughened sheet of the example of FIG. 1 . Sectional view. 3(a) to 3(c) are cross-sectional views showing an example of subsequent steps of FIGS. 2(a) to 2(c). Referring to Fig. 2 (a), in the production method of this example, support such as a hard material such as glass or an acrylic resin, a polycarbonate resin, or a polyester resin which is hard and transparent to active light such as ultraviolet rays is prepared. Substrate 7. In addition, as for the roughened sheet 1, for example, the reinforcing film 2, the binder resin 3 which forms the surface layer 5, and the fine particles 4 are all made of a material containing permeability to active light.

Moreover, the rough surfaced sheet is superposed on the upper surface 8 of the support substrate 7 with the mold surface 6 as the surface of the surface layer 5 as the upper surface and the opposite surface 9 as the exposed surface of the reinforcing film 2 as the lower side. 1. Specifically, for example, one end of the opposite surface 9 of the roughened sheet 1 is brought into contact with the surface 8 of the support substrate 7, and as shown by the arrow of the one-dot chain line in the figure, the roughened sheet 1 is self-surface 8 One end of the one end faces the other end and coincides in sequence.

The roughened sheet 1 which is superposed on the support substrate 7 is required to be relatively difficult to be applied by the shearing force when the photosensitive liquid resin composition is applied thereon, or the shrinking force at the time of curing of the photosensitive resin composition. A positional shift occurs in the support substrate 7, and replacement after use is easy. Therefore, for example, it is preferable that the roughened sheet 1 superposed on the support substrate 7 is attached and detachably fixed to the surface 8 of the support substrate 7 by any of the following methods (i) to (iii).

(i) The roughened sheet 1 is attached and detachably bonded to the surface 8 of the support substrate 7 by a weak adhesive layer containing a material which is transparent to the active light. (ii) A suction groove is formed on the surface 8 of the support substrate 7, and vacuum suction is performed through the suction groove, whereby the roughened sheet 1 is attached and detachably attached to the surface 8 of the support substrate 7. (iii) attaching/detaching the roughened sheet 1 to the surface 8 of the support substrate 7 by being detachably attached to and detached from the pair of chuck clamps spaced apart from each other in the surface direction of the support substrate 7. .

As the weak adhesion layer used for the adhesion fixation of (i), any of the following layers may be used: it has weak adhesion to both the support substrate 7 and the PET film as the reinforcement film 2, and includes transmission of active light. A layer of various adhesives. The weak adhesive layer is formed by applying a binder to at least one of the surface 8 of the support substrate 7 and the opposite surface 9 of the roughened sheet 1 by, for example, various coating methods such as spray coating.

After forming the weak adhesion layer, as shown by the arrow of the one-dot chain line in Fig. 2(a), the opposite surface 9 is set downward and the end of the surface 8 of the support substrate 7 is directed toward the other end to pay attention to the air. The roughened sheet 1 is sequentially overlapped while not entering. If so, the roughened sheet 1 is fixed to the surface 8 by the adhesive force of the weak adhesive layer. Further, when the fixed roughened sheet 1 is removed from the surface 8, for example, as opposed to the arrow of Fig. 2(a), the other end of the support substrate 7 is directed toward the one end while resisting the adhesion of the weak adhesive layer. It is sufficient to roughen the sheet 1 or the like.

In order to perform the adsorption fixation of (ii), the surface 8 of the support substrate 7 is finished to be smooth, and a suction groove is formed on substantially the entire surface of the surface 8. The suction tank is connected to a vacuum system including a vacuum pump or the like. Further, regarding the roughened sheet 1, the vacuum system is operated in a state in which the opposite surface 9 is placed below and superposed on the surface 8 of the support substrate 7, or the vacuum system that operates first is connected to the suction tank. In this manner, the superposed roughened sheet 1 is vacuum-attracted via the suction groove and fixed to the surface 8.

When the fixed roughened sheet 1 is removed from the surface 8, the vacuum system may be stopped or the connection between the vacuum system and the suction tank may be blocked. Next, referring to Fig. 2(b), in the manufacturing method of this example, a predetermined amount which is the basis of the original resin for printing is supplied onto the mold surface 6 of the roughened sheet 1 fixed to the surface 8 of the support substrate 7. Liquid photosensitive resin composition 10. The supplied photosensitive resin composition 10 is sandwiched between the roughened sheet 1 and the reinforcing sheet 11 which constitutes the printing resin original together with the photosensitive resin composition 10. Further, as shown by the arrow of the one-dot chain line in Fig. 2(b), one end of the surface 8 of the self-supporting substrate 7 is turned toward the other end so that the air does not enter the side and sequentially spreads to the rough surface. The die face 6 of the sheet 1 is formed. If so, the layer 12 of the photosensitive resin composition 10 is formed, and the reinforcing sheet 11 is laminated thereon.

Next, referring to Fig. 2(c), the opposing surface 14 of the counter substrate 13 is brought into contact with the reinforcing sheet 11. Further, the opposite faces 14 of the opposite substrate 13 are maintained at a certain interval and in parallel with the surface 8 of the support substrate 7, and the opposite substrate 13 is as shown by a black arrow in Fig. 2(c). The sheet 12 is pressed in the direction of the support substrate 7, so that the layer 12 is pressure-bonded to the die face 6 of the roughened sheet 1.

In this state, the layer 12 is irradiated with active light through the support substrate 7 and the roughened sheet 1 as indicated by the solid arrows in FIG. 2(c), thereby forming the photosensitive resin of the layer 12. The composition 10 is hardened. At this time, the interval between the surface 8 of the support substrate 7 and the opposing surface 14 of the counter substrate 13 is maintained in a size obtained by adding the thickness of the roughened sheet 1 to the thickness of the printed resin original plate. Settings.

Further, the counter substrate 13 may be formed of any material such as metal, glass, or hard resin. Among these, the counter substrate 13 can be formed of the same material as the support substrate 7 that is transparent to the active light, and the reinforcing sheet 11 can be formed of the same material that is transparent to the active light as the roughened sheet 1. In this case, for example, not only the side of the substrate 7 but also the layer 12 can be irradiated with active light from the opposite substrate 13 side to cure the photosensitive resin composition 10. Further, in this case, the photosensitive resin composition 10 can be cured only by irradiating the layer 12 with the active light rays from the opposite substrate 13 side. Therefore, for example, the roughened sheet 1 can be made of a material which is not transparent to the active light. form. 3(a) and 3(b), the reinforcing sheet 11 is taken out between the self-supporting substrate 7 and the counter substrate 13, and the layer 15 formed by curing the photosensitive resin composition 10 is roughened. The laminated body 16 of the sheet 1 is placed on the work table 17 with the reinforcing sheet 11 placed below.

Further, as shown by the arrow of the one-dot chain line in FIG. 3(b), the roughened sheet 1 is sequentially peeled off from one end of the laminated body 16 toward the other end. If so, the upper surface side in the drawing of the layer 15 is made into a roughened surface 18 of the rough surface shape on which the die face 6 of the roughened sheet 1 is transferred, thereby completing FIG. 3(c). The printing resin master 19 shown. As the photosensitive resin composition 10, any of various resin compositions satisfying the following conditions can be used. It can be hardened by irradiation with active light such as ultraviolet rays. After hardening, it has moderate softness or rubber elasticity suitable for flexographic printing. It is possible to form a cured product excellent in resistance (solvent resistance) to the solvent used in the printing of the ink used for printing or the cleaning of the printing plate.

The photosensitive resin composition which satisfies these conditions is not limited thereto, and examples thereof include a prepolymer having a 1,2-butadiene structure and having an ethylenic double bond at a terminal, and an ethylenically unsaturated monovalent amount. A photosensitive resin composition of a body and a photopolymerization initiator. As a photoinitiator, a benzoin alkyl ether is preferable. Further, as the reinforcing sheet 11, for example, a sheet containing various thermoplastic resins such as polyethylene (PE), polypropylene (PP), PET, tetrafluoroethylene/hexafluoropropylene copolymer (FEP), or the like can be used. The reinforcing sheet 11 is preferably permeable to active light as described above.

Thereafter, although not shown, the four sides of the printing resin original plate 19 are cut to trim the entire planar shape into a rectangular shape. Then, as shown in FIG. 4, for example, the layer 15 in the vicinity of the two sides parallel to each other is thermally cut off by laser processing or the like, and is formed by clamping at a vise of a printing machine (not shown). The pinching portion 20 or the chuck hole 21 for inserting the needle or the like. Further, a predetermined printing pattern is formed on the plate surface 18 as needed to complete the flexographic printing plate 22.

Further, in the example of the figure, the pinching portion 20 is formed to have a constant width by sandwiching the groove portion 23 having a constant width with the plate surface 18 over the entire width of the two sides of the flexographic printing plate 22. Further, the chuck holes 21 are formed at a plurality of positions (five positions in the drawing) in the longitudinal direction of the nip portion 20 at equal intervals. <Method for Producing Liquid Crystal Display Element> Using the roughened sheet of the present invention and using a flexographic printing plate having a small defect rate and excellent productivity, which is produced by the above method, a liquid crystal alignment film is formed by flexographic printing, thereby also The productivity of the liquid crystal display element can be improved.

The other steps of the method of manufacturing the liquid crystal display element can be carried out in the same manner as in the prior art. In other words, a transparent electrode layer corresponding to a predetermined matrix pattern or the like is formed on the surface of a transparent substrate such as a glass substrate, and a liquid crystal alignment film is formed by flexographic printing using a flexographic printing plate, and the liquid crystal alignment film is rubbed by friction or the like as necessary. The surface is subjected to alignment treatment to fabricate a substrate.

Then, two of the substrates are prepared, and the liquid crystal material is sandwiched therebetween while the respective transparent electrode layers are aligned, thereby forming a laminate, and further disposed on both outer sides of the laminate. A polarizing plate, thereby manufacturing a liquid crystal display element. The configuration of the present invention is not limited to the examples in the drawings described above. For example, in the method of producing a flexographic printing plate, the layer of the photosensitive resin composition can be coated and expanded by making the roughened sheet into a roll shape or the like, and the thickness thereof can be made constant, and at the same time, the surface thereof can be made. Roughening is used instead of pressing the counter substrate toward the support substrate.

Further, various modifications can be made without departing from the spirit and scope of the invention. [Examples]

Hereinafter, the present invention will be described based on examples and comparative examples, but the constitution of the present invention is not limited by these examples and comparative examples. <Example 1> (Roughened Sheet 1) As the binder resin 3, a main component (solid content: 50% by mass) containing an acrylic polyol and a curing agent containing an isocyanate (solid content: 60% by mass) were used. Acrylic polyurethane urethane 2-liquid hardening type acrylic resin. In the binder resin 3, acrylic resin particles (fine particles 4) are blended, and methyl ethyl ketone and butyl acetate as a solvent are further added to adjust the viscosity to prepare a coating agent for the surface layer 5. As the acrylic resin particles, the minimum value of the particle diameter distribution was 2.0 μm, the maximum value was 5.0 μm, the average particle diameter was 3.0 μm, the standard deviation σ was 0.8 μm, and the coefficient of variation Cv was 0.27.

As the reinforcing film 2, a PET film having a thickness of 0.075 mm which is subjected to a primer treatment on one side is used, and the coating agent is continuously applied on the one side while continuously conveying the PET film, and then subjected to a warm air drying step. The surface layer 5 is continuously formed, thereby continuously producing the roughened sheet 1 of the laminated structure shown in Fig. 1 . In addition, the adhesive resin 3 which has been subjected to the roughening of the roughened sheet 1 , the acrylic resin particles as the fine particles 4 , and the PET film are all selected to be transparent to the active light for producing the printing resin original. .

The roughened sheet 1 has an overall thickness of 0.080 mm, and the surface layer 5 has a thickness of 0.005 mm. <Example 2> A PET film (reinforcing film 2) having a thickness of 0.100 mm and a minimum particle size distribution of 4.0 μm, a maximum value of 20.0 μm, an average particle diameter of 12.0 μm, and a standard deviation σ of 3.3 μm were used. A roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a coefficient Cv of 0.28 were used.

The roughened sheet 1 has an overall thickness of 0.120 mm, and the surface layer 5 has a thickness of 0.020 mm. <Example 3> A PET film (reinforcing film 2) having a thickness of 0.125 mm and a minimum particle size distribution of 2.0 μm, a maximum value of 14.0 μm, an average particle diameter of 8.0 μm, and a standard deviation σ of 2.7 μm were used. A roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a coefficient Cv of 0.34 were used.

The roughened sheet 1 has an overall thickness of 0.140 mm, and the surface layer 5 has a thickness of 0.015 mm. <Example 4> A PET film (reinforcing film 2) having a thickness of 0.188 mm and a minimum particle size distribution of 5.0 μm, a maximum value of 30.0 μm, an average particle diameter of 18.0 μm, and a standard deviation σ of 6.0 μm were used. A roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a coefficient Cv of 0.33 were used.

The roughened sheet 1 has an overall thickness of 0.220 mm, and the surface layer 5 has a thickness of 0.032 mm. <Example 5> A PET film (reinforcing film 2) having a thickness of 0.250 mm and a particle size distribution having a minimum value of 10.0 μm, a maximum value of 30.0 μm, an average particle diameter of 20.0 μm, a standard deviation σ of 5.4 μm, and a coefficient of variation were used. A roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a Cv of 0.27 were used.

The roughened sheet 1 has an overall thickness of 0.285 mm, and the surface layer 5 has a thickness of 0.035 mm. <Example 6> A PET film (reinforcing film 2) having a thickness of 0.050 mm and a particle size distribution having a minimum value of 2.0 μm, a maximum value of 14.0 μm, an average particle diameter of 8.0 μm, a standard deviation σ of 2.9 μm, and a coefficient of variation were used. The roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a Cv of 0.36 were used.

The roughened sheet 1 has an overall thickness of 0.065 mm, and the surface layer 5 has a thickness of 0.015 mm. <Example 7> A PET film (reinforcing film 2) having a thickness of 0.300 mm and a minimum particle size distribution of 4.0 μm, a maximum value of 20.0 μm, an average particle diameter of 12.0 μm, and a standard deviation σ of 3.0 μm were used. A roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a coefficient Cv of 0.25 were used.

The roughened sheet 1 has an overall thickness of 0.320 mm, and the surface layer 5 has a thickness of 0.020 mm. <Comparative Example 1> A conventional method of continuously inserting a sheet of a urethane-based thermoplastic elastomer (TPU) and a reinforcing film between a roughening roll and a counter roll to form a die surface is reproduced. As the reinforcing film, a PET film having a thickness of 0.100 mm was used.

Further, as the TPU for the surface layer, an ester type TPU is used. The TPU is continuously extruded into a sheet shape by a die of an extruder to form a surface layer, and the surface layer is continuously inserted into the roughening roll and the counter roll together with the reinforcing film continuously supplied in a long strip before the surface layer is cooled and solidified. Between, and thus integrally laminated. At the same time, the rough surface shape of the original mold surface of the roughening roll was continuously transferred on the surface of the surface layer, thereby continuously producing a roughened sheet in which the surface was made into a roughened mold surface.

As the roughening roll, those whose outermost layer contains an anthrone rubber are used. The roughened sheet has an overall thickness of 0.110 mm and a surface layer thickness of 0.010 mm. <Comparative Example 2> A rough film was continuously produced in the same manner as in Comparative Example 1, except that a PET film having a thickness of 0.125 mm was used as the reinforced film, and the slit width of the mold was adjusted to have a thickness of the surface layer of 0.050 mm. Sheet.

The roughened sheet has an overall thickness of 0.175 mm. <Comparative Example 3> A rough film was continuously produced in the same manner as in Comparative Example 1, except that a PET film having a thickness of 0.188 mm was used as the reinforced film, and the slit width of the mold was adjusted to have a thickness of the surface layer of 0.080 mm. Sheet.

The roughened sheet has an overall thickness of 0.268 mm. <Evaluation of the unevenness of the rough surface shape> The unevenness of the rough surface shape of the mold surface of the roughened sheet produced in each of the examples and the comparative examples was visually observed, and evaluated based on the following criteria.

◎: The unevenness of the rough surface shape was not observed, and the rough surface shape was uniform. ○: A slight unevenness was observed in the rough surface shape. △: Unevenness was observed conspicuously in the rough surface shape than "○". ×: A region where a rough surface shape was not formed was observed. Further, in the comparative example, the smaller the thickness of the surface layer is, the more the amount of the rough surfaced roll is changed, and the unevenness of the rough surface shape tends to be large, and the unevenness is excessively large, resulting in complete untransfer (formation). The area of the rough surface shape is evaluated as "X".

<Processability Evaluation> The roughened sheets before the cutting in the respective examples and the comparative examples were observed by visually observing the state in which the respective mold faces were set to the outside and continuously wound into a roll shape. The treatment property was evaluated on the basis of the following criteria.

◎: It can be continuously wound 200 m or more without wrinkles. ○: In the range of 100 m or more and less than 200 m, continuous winding can be performed without wrinkles. △: In the range of 20 m or more and less than 100 m, continuous winding can be performed without wrinkles. X: Wrinkles were generated at less than 20 m, which affected the productivity of the roughened sheet 1.

<Evaluation of Fish Eye Number> The roughened sheets produced in the respective Examples and Comparative Examples were observed, and the number of fish eyes per unit area (number/m ² ) was counted. Further, the number of fish eyes was evaluated on the basis of the following criteria. ◎: The number of fish eyes is 0/m ² . ○: The number of fish eyes exceeds 0/m ² and is 0.1/m ² or less. ×: The number of fish eyes exceeds 0.1 / m ² .

<Evaluation of the number of broken defects> The number of roughened sheets before cutting in each of the examples and the comparative examples was wound into a roll shape, and then the number of broken defects per unit area generated during unwinding was measured. m ² ) is counted. Further, the fracture defects were evaluated on the basis of the following criteria.

◎: The number of fracture defects was 0.06 / m ² or less. ○: The number of fracture defects exceeded 0.06 / m ² and was 0.15 / m ² or less. △: The number of fracture defects exceeded 0.15 / m ² and was 0.40 / m ² or less. ×: The number of broken defects exceeded 0.40 / m ² . <Release evaluation> Using the roughened sheet produced in each of the examples and the comparative examples, the printing was carried out by the procedures of Figs. 2(a) to 2(c) and Figs. 3(a) to 3(c). After the resin original plate, the peel strength at the time of peeling the roughened sheet from the manufactured printing resin original plate at 180° was measured. Further, the peelability was evaluated on the basis of the following criteria. NK resin manufactured by Sumitomo Rubber Industries Co., Ltd. is used as a photosensitive resin composition which is the basis of the original resin for printing. Further, as the reinforcing sheet, a BF/CF laminated film manufactured by Sumitomo Rubber Industries Co., Ltd. was used.

◎: The peel strength was 0.15 N/mm or less, and it was easy to manually peel off. ○: The peel strength exceeds 0.15 N/mm and is 0.20 N/mm or less. Although it can be manually peeled off, it requires strength in comparison with "◎". △: The peel strength exceeds 0.20 N/mm and is 0.25 N/mm or less. Although it can be manually peeled off, it requires strength in comparison with "○". ×: The peel strength exceeded 0.25 N/mm, and it was not possible to peel off manually, and it was necessary to assist in peeling work.

<Comprehensive evaluation> All the evaluations were evaluated as A, and only ◎ and ○ were evaluated as B, and only one △ and others were ◎ or ○ were evaluated as C, Δ was two and others were ◎. Or the evaluation of ○ is D, and even if it is one ×, it is evaluated as E.

The above results are shown in Tables 1 to 3.

[Table 1]

[Table 2]

[table 3]

From the results of Tables 1 to 3, it was found that the roughened sheets of Examples 1 to 7 including the surface layer obtained by dispersing the fine particles in the binder resin were compared with Comparative Examples 1 to 3. There is no fisheye, the unevenness of the rough surface shape is small, and the handleability or peelability is excellent, and it is difficult to generate a fracture defect. In addition, it was found that by using the roughened sheets of Examples 1 to 7, the occurrence of defects can be suppressed, and the printing resin original plate and the flexographic printing plate can be produced with good productivity.

Further, from the results of Examples 1 to 7, it was found that the fine particles preferably have a minimum particle diameter distribution of 2.0 μm or more and a maximum particle diameter distribution of 30.0 μm in consideration of further improving the above effect. the following. Furthermore, it has been found that the thickness of the reinforcing film is preferably 0.050 mm or more, preferably 0.075 mm or more, particularly preferably 0.100 mm or more, and preferably 0.300 mm or less, preferably 0.250 mm or less, particularly preferably 0.200 mm or less, and further preferably It is 0.150 mm or less.

Furthermore, it has been found that the overall thickness of the roughened sheet is preferably 0.065 mm or more, preferably 0.080 mm or more, particularly preferably 0.120 mm or more, and preferably 0.320 mm or less, preferably 0.285 mm or less, particularly preferably 0.230 mm. Hereinafter, it is more preferably 0.175 mm or less.

<Example 8> A PET film (reinforcing film 2) having a thickness of 0.188 mm and a particle size distribution having a minimum value of 2.0 μm, a maximum value of 5.0 μm, an average particle diameter of 2.8 μm, a standard deviation σ of 0.7 μm, and a coefficient of variation were used. The roughened sheet 1 was produced in the same manner as in Example 1 except that the acrylic resin particles (fine particles 4) having a Cv of 0.25 were used. The roughened sheet 1 has an overall thickness of 0.195 mm, and the surface layer 5 has a thickness of 0.007 mm.

<Example 9> Acrylic resin particles (fine particles 4) having a minimum particle size distribution of 2.5 μm, a maximum value of 9.0 μm, an average particle diameter of 5.0 μm, a standard deviation σ of 1.0 μm, and a coefficient of variation Cv of 0.20 were used. The roughened sheet 1 was produced in the same manner as in Example 8 except the above. The roughened sheet 1 has an overall thickness of 0.199 mm, and the surface layer 5 has a thickness of 0.011 mm.

<Example 10> Acrylic resin particles (fine particles 4) having a minimum particle diameter distribution of 6.0 μm, a maximum value of 18.0 μm, an average particle diameter of 10.0 μm, a standard deviation σ of 1.9 μm, and a coefficient of variation Cv of 0.19 were used. The roughened sheet 1 was produced in the same manner as in Example 8 except the above. The roughened sheet 1 has an overall thickness of 0.208 mm, and the surface layer 5 has a thickness of 0.020 mm.

<Example 11> Acrylic resin particles (fine particles 4) having a minimum particle size distribution of 10.0 μm, a maximum value of 30.0 μm, an average particle diameter of 18.0 μm, a standard deviation σ of 3.2 μm, and a coefficient of variation Cv of 0.18 were used. The roughened sheet 1 was produced in the same manner as in Example 8 except the above. The roughened sheet 1 has an overall thickness of 0.221 mm, and the surface layer 5 has a thickness of 0.033 mm.

<Example 12> Acrylic resin particles (fine particles 4) having a minimum particle diameter distribution of 2.0 μm, a maximum value of 13.0 μm, an average particle diameter of 5.0 μm, a standard deviation σ of 1.7 μm, and a coefficient of variation Cv of 0.34 were used. The roughened sheet 1 was produced in the same manner as in Example 8 except the above. The roughened sheet 1 has an overall thickness of 0.203 mm, and the surface layer 5 has a thickness of 0.015 mm.

<Preparation of Liquid Crystal Alignment Film> Using the roughened sheet 1 produced in each of the examples, printing was performed through the steps of Figs. 2(a) to 2(c) and Figs. 3(a) to 3(c). The printed original resin 19 is processed by the resin original 19, and the flexographic printing plate 22 shown in Fig. 4 is produced. The manufactured flexographic printing plate 22 and anilox roll #220 [unit volume 6.5 cc/m ² ] were incorporated into a flexographic printing machine for liquid crystal alignment film printing [NAKAN] In the A45].

Then, an ink for a liquid crystal alignment film [OPTMER (registered trademark) AL17901 manufactured by JSR Co., Ltd.] is supplied to a flexographic printing machine, and printed on an electrode forming surface of an analog substrate for a liquid crystal display device. Thereafter, it was pre-dried at 120 ° C for 30 minutes to form a liquid crystal alignment film. The set thickness of the liquid crystal alignment film after pre-drying is set to 900 Å. As the dummy substrate, a dot was constructed at a density of 420 ppi in a region of 5 inches square. The pitch of the concavities and convexities is 3 μm to 15 μm, and the height is 0.3 μm to 1 μm.

<Evaluation of Thickness of Liquid Crystal Alignment Film> The state of the liquid crystal alignment film produced was visually observed, and the thickness unevenness was evaluated by the following criteria. ◎: There is no unevenness in the thickness of the liquid crystal alignment film, and the thickness is uniform. ○: A slight thickness unevenness was observed in the liquid crystal alignment film. △: Thickness unevenness was observed in the liquid crystal alignment film more clearly than "○". ×: A region where the liquid crystal alignment film was not formed was observed. The results are shown in Table 4.

[Table 4]

According to the results of Examples 8 to 12 of Table 4, it is considered that, as described above, it is considered that the unevenness of the rough surface shape is small, and a liquid crystal alignment film having a uniform thickness without thickness unevenness is formed by a flexographic printing method. Further, the coefficient of variation Cv indicating the variation in the particle size distribution is preferably 0.35 or less, and particularly preferably 0.25 or less.

<Example 13> A rough surface was produced in the same manner as in Example 1 except that a PET film (reinforced film 2) having a thickness of 0.188 mm and mixed particles (fine particles 4) of two kinds of fine particles having different particle diameter distributions were used. Sheet 1. The fine particles are combined in the following two types. Fine particle A: Acrylic resin particles having a minimum particle size distribution of 2.0 μm, a maximum value of 3.6 μm, an average particle diameter of 2.8 μm, a standard deviation σ of 0.3 μm, and a coefficient of variation Cv of 0.11. Fine particle B: an acrylic resin particle having a minimum particle size distribution of 3.5 μm, a maximum value of 6.5 μm, an average particle diameter of 5.0 μm, a standard deviation σ of 1.0 μm, and a coefficient of variation Cv of 0.20.

The blending ratio of the fine particles A and the fine particles B is set to A: B = 65:35 by mass ratio, and the ratio of the fine particles A to the total amount of the mixed particles is 65% by mass. The coefficient of variation Cv of the whole of the mixed particles including the fine particles A and the fine particles B was 0.34. Further, the roughened sheet 1 has an overall thickness of 0.199 mm, and the surface layer 5 has a thickness of 0.011 mm.

<Example 14> A roughened sheet 1 was produced in the same manner as in Example 13 except that the mixed particles (fine particles 4) of the following two kinds of fine particles were used. Fine particle A: an acrylic resin particle having a minimum particle size distribution of 4.0 μm, a maximum value of 6.0 μm, an average particle diameter of 5.0 μm, a standard deviation σ of 0.4 μm, and a coefficient of variation Cv of 0.08. Fine particle B: an acrylic resin particle having a minimum particle size distribution of 5.0 μm, a maximum value of 9.0 μm, an average particle diameter of 7.0 μm, a standard deviation σ of 1.4 μm, and a coefficient of variation Cv of 0.20.

The blending ratio of the fine particles A and the fine particles B is set to A: B = 85:15 by mass ratio, and the ratio of the fine particles A to the total amount of the mixed particles is 85% by mass. The coefficient of variation Cv of the whole of the mixed particles including the fine particles A and the fine particles B was 0.18. Further, the roughened sheet 1 has an overall thickness of 0.203 mm, and the surface layer 5 has a thickness of 0.015 mm.

<Example 15> A roughened sheet 1 was produced in the same manner as in Example 13 except that the mixed particles (fine particles 4) of the following two kinds of fine particles were used. Fine particle A: an acrylic resin particle having a minimum particle size distribution of 5.7 μm, a maximum value of 8.3 μm, an average particle diameter of 7.0 μm, a standard deviation σ of 0.5 μm, and a coefficient of variation Cv of 0.07. Fine particle B: an acrylic resin particle having a minimum particle size distribution of 3.1 μm, a maximum value of 13.0 μm, an average particle diameter of 10.0 μm, a standard deviation σ of 1.9 μm, and a coefficient of variation Cv of 0.19.

The blending ratio of the fine particles A and the fine particles B is set to A: B = 75:25 by mass ratio, and the ratio of the fine particles A to the total amount of the mixed particles is 75% by mass. The coefficient of variation Cv of the whole of the mixed particles including the fine particles A and the fine particles B was 0.21. Further, the roughened sheet 1 has an overall thickness of 0.208 mm, and the surface layer 5 has a thickness of 0.020 mm. <Example 16> A roughened sheet 1 was produced in the same manner as in Example 13 except that the mixed particles (fine particles 4) of the following two kinds of fine particles were used.

Fine particle A: an acrylic resin particle having a minimum particle size distribution of 2.0 μm, a maximum value of 4.0 μm, an average particle diameter of 2.8 μm, a standard deviation σ of 0.7 μm, and a coefficient of variation Cv of 0.25. Fine particle B: an acrylic resin particle having a minimum particle size distribution of 4.0 μm, a maximum value of 6.0 μm, an average particle diameter of 5.0 μm, a standard deviation σ of 0.4 μm, and a coefficient of variation Cv of 0.08. The blending ratio of the fine particles A and the fine particles B is set to A: B = 10:90 by mass ratio, and the ratio of the fine particles A to the total amount of the mixed particles is 10% by mass. The coefficient of variation Cv of the whole of the mixed particles including the fine particles A and the fine particles B was 0.17. Further, the roughened sheet 1 has an overall thickness of 0.196 mm, and the surface layer 5 has a thickness of 0.008 mm.

<Evaluation of presence or absence of moiré stripe> The flexographic printing plate 22 was produced by using the roughened sheet 1 produced in each of the examples and in accordance with the procedure of "production of a liquid crystal alignment film", and the manufactured flexographic printing plate 22 was printed to The electrode forming surface of the analog substrate for a liquid crystal display element was pre-dried at 120 ° C for 30 minutes to form a liquid crystal alignment film. The set thickness of the liquid crystal alignment film after pre-drying is set to 900 Å. As the dummy substrate, a dot was constructed at a density of 420 ppi in a region of 5 inches square. The pitch of the concavities and convexities is 3 μm to 15 μm, and the height is 0.3 μm to 1 μm. Moreover, the state of the liquid crystal alignment film formed was visually observed, and the presence or absence of the moire fringe was evaluated based on the following criteria.

◎: There is no moire fringe in the liquid crystal alignment film, and the thickness is uniform. ○: A slight moire fringe was observed in the liquid crystal alignment film. △: Moiré fringes were observed conspicuously in the liquid crystal alignment film than "○". X: Moiré fringes were observed conspicuously in the liquid crystal alignment film than "Δ". The results are shown in Table 5.

[table 5]

According to the results of Examples 13 to 16 of Table 5, it is considered that, in particular, when a liquid crystal alignment film having no moire fringes is formed on the electrode formation surface of the substrate for a liquid crystal display element, it is preferable that the fine particles are fine particles. Mixed particles of two kinds of fine particles having different particle diameter distributions are used. In addition, it is considered that the coefficient of variation Cv of the entire mixed particles is preferably 0.15 or more in the range of 0.35 or less, and preferably 0.18 or more, and particularly preferably 0.20 or more.

1‧‧‧Rough surfaced sheet

2‧‧‧Enhanced film

3‧‧‧Binder resin

4‧‧‧Microparticles

5‧‧‧ surface layer

6‧‧‧Mold face

7‧‧‧Support substrate

8‧‧‧ surface

9‧‧‧ opposite side

10‧‧‧Photosensitive resin composition

11‧‧‧Enhanced sheet

12 ‧ ‧ layer

13‧‧‧ opposite substrate

14‧‧‧ opposite

15 ‧ ‧ layer

16‧‧‧Laminated body

17‧‧‧Working table

18‧‧‧ version surface

19‧‧‧Printing resin original

20‧‧‧Clamping Department

21‧‧‧ chuck hole

22‧‧‧Flexible printing

23‧‧‧Slots

Fig. 1 is a cross-sectional view showing an enlarged layer structure of an example of a roughened sheet of the present invention. 2(a) to 2(c) are cross-sectional views showing an example of a procedure for producing a resin plate for printing by using the roughened sheet of the example of Fig. 1 and using the production method of the present invention. 3(a) to 3(c) are cross-sectional views showing an example of subsequent steps of Figs. 2(a) to 2(c). 4 is a perspective view showing an example of a flexographic printing plate produced by using a printing resin original plate produced by the manufacturing methods of FIGS. 2( a ) to 2 ( c ) and 3 ( a ) to 3 ( c ).

Claims (10)

A roughened sheet for use in the production of a resin original for printing, and comprising at least a surface layer on which a surface is made into a roughened surface, and a reinforcing film provided on the back side of the surface layer, the surface layer The binder resin and the fine particles dispersed in the binder resin are contained, and at least a part of the fine particles protrude from the surface of the surface layer, so that the surface is made into a roughened mold surface. The roughened sheet according to claim 1, wherein a minimum value of the particle size distribution of the fine particles is 2.0 μm or more, and a maximum value of the particle diameter distribution is 30.0 μm or less. The roughened sheet according to the first or second aspect of the invention, wherein the coefficient of variation Cv of the fine particles indicating a variation in particle size distribution is 0.35 or less. The roughened sheet according to the first or second aspect of the invention, wherein the fine particles are mixed particles of two kinds of fine particles having different particle diameter distributions. The roughened sheet according to the fourth aspect of the invention, wherein the coefficient of variation Cv of the mixed particles indicating a deviation in particle size distribution is 0.35 or less. The roughened sheet according to any one of claims 1 to 5, wherein the reinforcing film has a thickness of 0.075 mm or more and 0.250 mm or less. The roughened sheet according to any one of claims 1 to 6, wherein the reinforcing film, the binder resin, and the fine particles each contain permeability to active light. material. A method of producing a resin original plate for printing, comprising the step of: contacting the layer of the photosensitive resin composition with the roughened sheet according to any one of the first to seventh aspects of the invention In the state of the die face, the layer is cured by irradiation with active rays and then peeled off from the die face, thereby transferring the die face on the face of the layer in contact with the die face. The rough surface shape is such that the surface is made into a roughened surface. A method for producing a flexographic printing plate, comprising the steps of thermally cutting a corresponding portion of a printing resin original plate manufactured by the manufacturing method according to claim 8 of the patent application to form a pliers for mounting on a printing machine Entry, and chuck holes. A method of producing a liquid crystal display element comprising the steps of forming a liquid crystal alignment film by flexographic printing using a flexographic printing plate manufactured by the manufacturing method as described in claim 9 of the patent application.