TW201800255A - Surface-roughened sheet and use thereof - Google Patents

Abstract

To provide a surface-roughened sheet having little generation of fish-eye defects and excellent productivity compared to the existing ones. A surface-roughened sheet includes a substrate film made of PET and a surface layer made of a thermoplastic elastomer having affinity to PET and TPU disposed on the substrate film via an intermediate layer made of a thermoplastic elastomer, in which the surface of the surface layer is formed into a mold surface. The method for manufacturing a resin original plate for printing and a flexographic printing plate includes a step of roughening a plate surface by using the above surface-roughened sheet. The method for manufacturing a liquid crystal display element includes a step of forming a liquid crystal alignment film by using the above flexographic printing plate.

Description

Method for producing roughened sheet and printing resin original plate using the same, method for producing flexographic printing plate, and method for producing liquid crystal display element

The present invention relates to a roughened sheet in the manufacture of a printing resin original plate used as a raw material for a flexographic printing plate, a method for producing a roughened resin original plate using the same, and a flexographic plate produced from the printing resin original plate. A method for manufacturing a flexographic printing plate for a printing plate, and a method for manufacturing a liquid crystal display element using the flexographic printing plate.

In order to form a liquid crystal alignment film having a high coating film quality, which is required to be as uniform as possible without pinholes and thin, on the electrode formation surface of the substrate constituting the liquid crystal display element, a flexographic printing method having good printing characteristics is used.

In the flexographic printing method, a flexographic printing plate may be used. The flexographic printing plate includes a flexible resin sheet, and the surface thereof is in contact with the electrode forming surface in a state in which an ink serving as a raw material such as a liquid crystal alignment film is carried. The surface to be printed becomes the surface on which the ink is transferred to the surface to be printed, that is, the surface of the plate.

In order to improve the wettability of the ink and to keep the ink well, and to transfer the held ink to the printing surface, the plate surface of the flexographic printing plate is generally formed to have a predetermined surface roughness. Degree of rough surface.

Patent Document 1 describes a method for producing a printing resin original plate in which a photosensitive resin composition that is a raw material of a sheet of the resin (printing resin original plate) is formed on the surface as a roughened mold surface. In a state where the roughened sheet is coated and spread into a layered state, after the hardening reaction is performed by irradiation with actinic rays such as ultraviolet rays, the roughened sheet is peeled from the sheet formed by the hardening reaction, thereby The rough surface shape is transferred to the surface of the sheet that is in contact with the die surface, and the surface is formed as a roughened plate surface.

According to the manufacturing method, a resin original plate for printing in which the entire surface of the plate surface is roughened with good productivity and low cost can be manufactured.

As the roughened sheet, for example, as described in Patent Document 1, since it has high affinity or wettability with the photosensitive resin composition, it is possible to use a material including a roughened surface that can mold the surface. A sheet of a urethane-based thermoplastic elastomer (thermoplastic polyurethane (TPU)) having a good shape transferred to the surface of the printing plate of the original resin for printing. For example, a polyethylene terephthalate (PET) film is laminated on the opposite side as a reinforcing film.

The roughened sheet can be produced, for example, by extruding TPU into a sheet shape, and continuously inserting it with a reinforcing film between a roughened roll and a counter roll, and cutting it as necessary With a predetermined size, the outer peripheral surface of the roughened roller is formed into a rough surface shape model surface corresponding to the rough surface shape of the die surface of the roughened sheet.

That is, a sheet of a TPU and a reinforcing film are laminated to each other by the pressure at the time of insertion, and the rough surface shape of the model surface is transferred to the surface of the sheet, and the surface is formed as a rough surface Die surface.

However, in the conventional roughened sheet, when synthesizing a TPU, a partial gelatinous substance called a fisheye is generated, and if the fisheye is sandwiched between the fisheye and a reinforcing film, it is on the mold surface. When local protrusions are generated, there is a problem that depressions corresponding to the protrusions are generated on the plate surface of the resin original plate for printing, and the flatness of the plate surface is damaged.

As far as the synthesis mechanism of TPU is concerned, it is difficult to completely remove fish eyes, and after lamination, the roughened sheet before cutting must contain a lot of fish eyes.

Therefore, when manufacturing a roughened sheet, it is necessary to select a region where fish eyes are not generated after confirming the positions where the fish eyes are generated, and material waste is increased.

In addition, the part of the gel-like substance forming the fish eye is basically the same component as the TPU. Since the color and appearance are almost the same, a large amount of inspection is required to confirm the position during the cutting or to check the roughened sheet after the cutting. Labor and time. Therefore, these cases are combined with each other and there is a problem that the productivity of the rough sheet is lowered.

In addition, if, for example, a roughened sheet that has missed fish eyes during inspection is used in the manufacture of a printing original resin plate, there may be depressions on the surface of the plate as described above, and defective products that cannot be used in printing may be produced. As a result, the defective rate of the printing resin original plate and further the flexographic printing plate is increased, the productivity is lowered, and finally the productivity of the liquid crystal display element is also lowered. [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent No. 5427225

[Problems to be Solved by the Invention] An object of the present invention is to provide a roughened sheet that has less fisheye generation and is more excellent in productivity than the current situation. Another object of the present invention is to provide a method for producing a resin original plate for printing and a flexographic printing plate with good productivity by suppressing the occurrence of defects by using the roughened sheet.

Furthermore, an object of the present invention is to provide a manufacturing method for manufacturing a liquid crystal display element using the flexographic printing plate, which is more productive and inexpensive at present than the current situation. [Means for solving problems]

The present invention is a roughened sheet for use in manufacturing a resin original plate for printing, and the roughened sheet is characterized by comprising: a reinforcing film; an intermediate layer provided on one side of the reinforcing film; and a surface layer Is disposed on the intermediate layer, the surface is formed as a roughened mold surface, the surface layer comprises a urethane-based thermoplastic elastomer, the reinforcing film is a polyethylene terephthalate film, and The intermediate layer includes a thermoplastic elastomer having an affinity for the urethane-based thermoplastic elastomer and the polyethylene terephthalate.

In addition, the present invention is a method for producing a printing resin original plate. The method for producing a printing resin original plate includes a step of contacting a layer of a photosensitive resin composition with the roughened sheet of the present invention. In the state of the mold surface, the rough surface shape of the mold surface is transferred to and from the layer by peeling the layer from the mold surface after performing a hardening reaction by irradiation with actinic rays. The surface in which the mold surface contacts, thereby forming the surface as a roughened plate surface.

Furthermore, the present invention is a method for manufacturing a flexographic printing plate. The method for manufacturing a flexographic printing plate includes the steps of thermally cutting off a corresponding part of a printing resin original plate manufactured by the manufacturing method of the present invention to form It is used to install in the bite part of the printing press and the chuck hole. Furthermore, the present invention is a method for manufacturing a liquid crystal display element, which includes the steps of forming a liquid crystal alignment by flexographic printing using a flexographic printing plate manufactured by the manufacturing method of the present invention. membrane. [Effect of the invention]

According to the present invention, it is possible to provide a roughened sheet with less fisheye generation and more excellent productivity than the current situation. In addition, according to the present invention, it is possible to provide a method for manufacturing a resin original plate for printing and a flexographic printing plate with good productivity by suppressing the occurrence of defects by using the roughened sheet.

Furthermore, according to the present invention, it is possible to provide a manufacturing method for manufacturing a liquid crystal display element using the above-mentioned flexographic printing plate, which is more productive and inexpensive at present compared to the current situation.

<Roughened Sheet> FIG. 1 is an enlarged sectional view showing an example of a layer structure of an embodiment of a roughened sheet according to the present invention. FIG. 2 is a diagram illustrating an example of a step of manufacturing the roughened sheet of the example shown in FIG. 1.

Referring to FIG. 1, the roughened sheet 1 of this example is formed by sequentially laminating an intermediate layer 3 and a surface layer 4 including a TPU on one side (the upper surface in the figure) of a PET film as a reinforcing film 2, and The exposed surface of the surface layer 4 is formed as a roughened mold surface 5.

Referring to FIG. 2, in the manufacturing method of the roughened sheet 1 of this example, first, two kinds of molten resins serving as raw materials for the intermediate layer 3 and the surface layer 4 are connected to two extruders (not shown) through two The die 6 for layer extrusion is continuously extruded in a sheet shape and in a state of being stacked on each other.

Then, the intermediate layer 3 before cooling and solidification, and the laminate of the surface layer 4 and the reinforcing film 2 continuously supplied in a long strip are continuously inserted into the roughened roller as shown by the two-dot chain line arrows in the figure. 7 and 8 pairs of rollers. At this time, the exposed surface (the right side surface in the figure) of the surface layer 4 is in contact with the roughened surface roller 7.

Regarding the roughening roller 7, the outermost layer 9 including the outer peripheral surface thereof contains, for example, silicone rubber, and the outer peripheral surface is formed into a model of a rough surface shape corresponding to the rough surface (die surface 5) formed on the surface of the surface layer 4.面 10。 Face 10. Regarding the roughened roll 7, as shown by the white arrow in the figure, a predetermined rolling pressure is applied in the direction of the roll 8, and it is crimped to the right surface of the surface layer 4 in the figure.

In addition, the counter roller 8 functions not only as a support roller for the crimping, but also as a cooling roller (not shown) including a cooling mechanism. The cooling roller is used to cool the intermediate layer 3 and the surface layer 4. It cures.

Therefore, by inserting between the two rolls 7 and 8, the surface layer 4, the intermediate layer 3, and the reinforcing film 2 are integrally laminated, and the roughened roller 7 is continuously transferred on the surface of the surface layer 4. The rough surface shape of the mold surface 10 is formed, so that the rough surfaced sheet 1 having the layer structure shown in FIG. 1 formed as the roughened mold surface 5 is continuously manufactured.

The produced roughened sheet 1 is further cut to a predetermined length and the like as necessary, and is used for producing a resin original plate for printing. The surface layer 4 in the roughened sheet 1 may be formed of TPU in the same manner as before.

Examples of the TPU include an ester-type or ether-type TPU. Among them, an ester-type TPU is preferred. As the ester-type TPU, for example, it is preferred to use a PANDEX (registered trademark) T-series TPU manufactured by DIC Covestro Polymer (stock), and in particular, it has the transmission of actinic rays. Sex.

The intermediate layer 3 may be formed of a thermoplastic elastomer other than TPU (except TPU) having an affinity for the TPU forming the surface layer 4 and the PET film as the reinforcing film 2. As the thermoplastic elastomer, various thermoplastic elastomers other than TPU having the above-mentioned functions can be used.

That is, examples of the thermoplastic elastomer include at least one selected from the group consisting of an olefin-based thermoplastic elastomer, a styrene-based thermoplastic elastomer, a polyester-based thermoplastic elastomer, and a polyamide-based thermoplastic elastomer. Particularly preferred is an olefin-based thermoplastic elastomer.

Examples of the olefin-based thermoplastic elastomer include an ethylene-based thermoplastic elastomer and a propylene-based thermoplastic elastomer. Among these, a propylene-based thermoplastic elastomer is preferred, and a random copolymer or a block copolymer of one or more monomers selected from α-olefins other than ethylene and propylene and propylene is particularly preferred.

Examples of the α-olefins other than ethylene and propylene include at least one of butene, pentene, hexene, heptene, octene, decene, and dodecene. Specific examples of the propylene-based thermoplastic elastomer include, for example, Mitsui Chemicals, which controls the structure of a crystalline portion and an amorphous portion in a molecule at a nanometer level to improve heat resistance, flexibility, and transmission of actinic rays. Stock) manufactured by TAFMER (registered trademark) PN series of propylene-based thermoplastic elastomers.

In order to integrate the surface layer 4 and the reinforcing film 2 well, the intermediate layer 3 containing a thermoplastic elastomer is interposed between the surface layer 4 and the reinforcing film 2 to reduce the thickness of the surface layer 4 to be rough. The surface functions as a proportion of the total thickness of the sheet 1.

That is, by replacing a part of the thickness of the TPU layer of the existing roughened sheet with the intermediate layer 3, the thickness of the surface layer 4 including the TPU can be reduced and the amount of TPU forming the surface layer 4 can be reduced. As a result, the amount of fish eyes can be reduced, and the number of protrusions caused by the fish eyes can be suppressed.

Therefore, the proportion of areas where no fish eyes are generated can be increased compared to the current situation, the waste of materials at the time of cutting can be reduced, and the position confirmation at the time of cutting or the inspection of the roughened sheet after cutting can be reduced Labor and time can improve the productivity of the roughened sheet 1 as a result. The reinforcing film 2 has a function of literally enhancing the tensile strength and the like of the roughened sheet 1 as a whole, and also functions to correct the warpage of the roughened sheet 1.

That is, if the reinforcing film 2 is omitted, and only the thermoplastic elastomer serving as the raw material of the intermediate layer 3 and the TPU serving as the raw material of the surface layer 4 are simultaneously extrusion-molded and laminated with each other, there is a possibility that it is based on the difference in shrinkage of the two elastomers. A concave warpage (mountain warpage) occurs on the roughened sheet, especially on the intermediate layer 3 side, which has a large shrinkage, thereby reducing the planarity of the surface of the printing resin original plate produced using the roughened sheet. .

In contrast, if the reinforcing film 2 is laminated on the opposite surface of the intermediate layer 3, the occurrence of the warpage can be suppressed. As the reinforcing film 2, a PET film can be used as described above. A PET film having transmissivity to actinic rays is particularly preferred.

The PET film is excellent in functions such as enhancement and warpage correction, and also has excellent affinity with TPU. Among the above layers, the thickness of the surface layer 4 is preferably 0.01 mm or more and 0.06 mm or less.

It is not easy to smoothly mold the surface layer 4 having a thickness less than this range, and further the laminate of the surface layer 4 and the intermediate layer 3 into a sheet shape by the extrusion molding, and uneven thickness or resin may occur. Break etc.

On the other hand, when the thickness of the surface layer 4 exceeds the above range, it may not be possible to sufficiently obtain the effect of reducing the thickness of the surface layer 4 by interposing the intermediate layer 3 as described above, thereby suppressing the fish-eye effect. produce. In contrast, by setting the thickness of the surface layer 4 within the above range, it is possible to more reliably suppress the occurrence of fish eyes while maintaining good moldability.

In order to reduce the thickness of the surface layer 4 as described above, the thickness of the intermediate layer 3 is preferably larger than the thickness of the surface layer 4, and particularly preferably 0.07 mm or more and 0.20 mm or less.

It is not easy to smoothly mold the intermediate layer 3 having a thickness less than this range, and further, the laminated body of the intermediate layer 3 and the surface layer 4 into a sheet shape by the extrusion molding, and unevenness or thickness may occur. Resin breaks, etc.

In addition, although it also depends on the thickness of the surface layer 4, the total thickness of the two layers that transfer the rough surface shape of the mold surface 10 by the manufacturing method is reduced, so that the rough surface shape may not be sufficiently reproduced.模 面 5。 Die surface 5.

Furthermore, although it also depends on the thickness of the surface layer 4, the roughened sheet 1 is easily bent, and if it is bent, it may also be in the rough surface shape of the die surface 5, and then the flexographic printing plate surface. Defects (bending defects) occur, and problems such as the inability to form a uniform and continuous liquid crystal alignment film can occur.

On the other hand, when the thickness of the intermediate layer 3 exceeds the above range, although the thickness of the surface layer 4 also depends, the weight of the roughened sheet 1 increases and it becomes difficult to make the roughened sheet 1 Bending or curling, for example, it is possible to take up a long roughened sheet 1 before cutting, or use a roughened sheet 1 made by cutting to manufacture a resin original plate for printing, or to perform Handling properties and the like are reduced when storage is performed and the winding process is performed.

On the other hand, by setting the thickness of the intermediate layer 3 within the above range, it is possible to reliably suppress the occurrence of various problems while maintaining good moldability. Taking into consideration the case of improving the handling properties and the like, the total thickness of the roughened sheet 1 is preferably 0.45 mm or less.

In addition, therefore, the upper limit of the total thickness of the surface layer 4 and the intermediate layer 3 is preferably set to be less than the thickness obtained by subtracting the thickness of the reinforcing film 2 from the upper limit of the total thickness. The thickness of the reinforcing film 2 is preferably 0.05 mm or more, and preferably 0.19 mm or less.

If the thickness is less than this range, the reinforcing film 2 and then the roughened sheet 1 will be easily bent during the above-mentioned processing and the like. If bending occurs, there is a possibility that the reinforcing film 2 and the flexographic printing plate may occur on the die surface 5. Bending defects occur in the rough surface shape of the plate surface, and a problem such as the inability to form a uniform and continuous liquid crystal alignment film is generated.

In addition, the effect of correcting the warpage due to the provision of the reinforcing film 2 becomes insufficient, and there is a possibility that the flatness of the plate surface of the printing resin original plate produced using the roughened sheet 1 may be reduced.

On the other hand, when the thickness of the reinforcing film 2 exceeds the range, the weight of the roughened sheet 1 increases, and it becomes difficult to bend or curl the roughened sheet 1, so that the processing may be performed. Sex and so on.

In contrast, by setting the thickness of the reinforcing film 2 to the above range, it is possible to suppress the occurrence of bending as much as possible, and at the same time to improve the handleability of the roughened sheet and the like. Furthermore, in consideration of suppressing the occurrence of bending more favorably, the thickness of the reinforcing film 2 is preferably 0.10 mm or more in the above range.

<Manufacturing Method of Resin Original Plate for Printing and Flexographic Printing Plate> Figs. 3 (a) to 3 (c) show the use of the roughened sheet shown in Fig. 1 to produce a resin original plate for printing by the production method of the present invention. A cross-sectional view of an example of the steps. 4 (a) to 4 (c) are cross-sectional views showing an example of subsequent steps of FIGS. 3 (a) to 3 (c).

Referring to FIG. 3 (a), in the method for manufacturing a printing resin original plate of this example, first, a glass or a hard resin containing an acrylic resin, a polycarbonate resin, a polyester resin, or the like, and an actinic ray having ultraviolet rays or the like is prepared. A support substrate 11 of a permeable material.

Then, on the upper surface 12 in the figure of the support substrate 11, the opposite surface 13 is brought into contact with the mold surface 5 as the surface of the surface layer 4 as the upper surface and the opposite surface 13 as the surface of the reinforcing film 2 as the lower surface. On the surface 12 of the support substrate 11, the roughened sheet 1 of the present invention including three layers of a reinforcing film 2, an intermediate layer 3, and a surface layer 4, as shown by a dashed-dotted arrow in the figure, is removed from the surface. One end to the other end of the surface 12 is sequentially overlapped, etc., and is detachably fixed.

Regarding the roughened sheet 1, the cutting force when the photosensitive resin composition in the form of an extended liquid is applied to the roughened sheet 1 or the shrinking force when the photosensitive resin composition is cured is used. It is preferable to prevent the positional displacement with respect to the support substrate 11 and facilitate the exchange of the roughened sheet 1 after use. For example, it is preferable to be detachable by any of the following methods (i) to (iii). It is fixed to the surface 12 of the support substrate 11.

(I) Removably adhered and fixed through a weak adhesive layer containing a material having permeability to actinic rays. (Ii) The suction groove is formed on the surface 12 of the support substrate 11 and vacuum suction is performed through the suction groove, so that the suction groove is detachably fixed. (Iii) It is detachably press-bonded and fixed in a state of being extended between a pair of chuck clamps which are spaced apart from each other by a larger interval than the surface direction of the support substrate 11.

Among them, as the weak adhesion layer used in the (i) adhesion fixing, any one of layers including a plurality of adhesives may be used, and the adhesive is provided for the support substrate 11 and the PET film as the reinforcing film 2 Weak adhesion and transmission to actinic rays. The weak adhesion layer can be formed by applying the adhesive to at least one of the surface 12 of the support substrate 11 and the opposite surface 13 of the roughened sheet 1 by various coating methods such as spray coating. .

After the weak adhesion layer is formed, take care not to allow air to enter between the roughened sheet and the surface 12 of the support substrate 11, and use the opposite surface 13 as a down arrow as shown by a dashed line in FIG. 3 (a). After the roughened sheet 1 is sequentially stacked from one end to the other end of the surface 12 of the support substrate 11 as shown, the roughened sheet 1 is fixed to the surface 12 by the adhesive force of the weak adhesive layer.

In addition, in order to remove the fixed roughened sheet 1 from the surface 12, as long as it resists the adhesive force of the weak adhesive layer, it goes from the other end to the one end of the support substrate 11 opposite to the arrow of FIG. 3 (a), for example. The roughened sheet 1 may be peeled off in order. In order to perform (ii) adsorption fixation, the surface 12 of the support substrate 11 is finished to be smooth, and a suction groove is formed on substantially the entire surface of the surface 12. The suction tank is connected to a vacuum system including a vacuum pump and the like.

Then, the vacuum system is operated in a state where the roughened sheet 1 is superposed on the surface 12 of the support substrate 11 with the opposite surface 13 as the lower surface, or a vacuum system that is operated in advance is connected to the suction tank, and the like is passed through the suction tank. After the vacuum suction is performed, the roughened sheet 1 is fixed on the surface 12. In order to remove the fixed roughened sheet 1 from the surface 12, the vacuum system may be stopped or the connection between the vacuum system and the suction tank may be blocked.

Referring to FIG. 3 (b), in the manufacturing method of this example, a predetermined amount of a liquid photosensitive resin composition 14 serving as a raw material of a printing resin original plate is supplied to a surface 12 fixed to a support substrate 11. On the die surface 5 of the roughened sheet 1.

Then, the supplied photosensitive resin composition 14 is sandwiched between the reinforcing sheet 15 constituting the printing resin original plate together with the photosensitive resin composition 14 and the roughened sheet 1 while taking care not to allow air. Entered between the photosensitive resin composition 14 and the mold surface 5 of the roughened sheet 1, while moving from one end to the other end of the surface 12 of the support substrate 11 as shown by the dashed-dotted arrow in FIG. 3 (b). The coating 16 is sequentially spread on the die surface 5 of the roughened sheet 1 to form a layer 16 of the photosensitive resin composition 14, and a reinforcing sheet 15 is laminated thereon.

Next, referring to FIG. 3 (c), the facing surface 18 of the facing substrate 17 is brought into contact with the reinforcing sheet 15. Then, while maintaining the object surface 18 in parallel with a certain interval from the surface 12 of the support substrate 11, the opposing substrate 17 is directed toward the support substrate 11 as shown by the black arrow in FIG. 3 (c). By pressing, the layer 16 is brought into pressure contact with the die surface 5 of the roughened sheet 1.

Then, in this state, as shown by the solid line arrows in FIG. 3 (c), the layer 16 is irradiated with actinic rays through the support substrate 11 and the roughened sheet 1, so that the layer 16 is formed. The photosensitive resin composition 14 undergoes a curing reaction. At this time, the interval between the surface 12 of the supporting substrate 11 and the opposing surface 18 of the opposing substrate 17 is a size obtained by increasing the thickness of the roughened sheet 1 while maintaining the thickness of the manufactured resin original plate. Way to set.

The counter substrate 17 may be formed of any material such as metal, glass, and hard resin. In particular, the counter substrate 17 is formed of the same material as the supporting substrate 11 and has a permeability to actinic rays, and the reinforcing sheet 15 is also formed of a material having a permeability to actinic rays. The layer 16 is irradiated with actinic rays from the opposite substrate 17 side, and the photosensitive resin composition 14 undergoes a curing reaction.

In addition, for example, in the case where at least one of the layers 2 to 4 forming the roughened sheet 1 includes a material having no permeability to actinic rays and the roughened sheet 1 does not have permeability to actinic rays Next, the layer 16 may be irradiated with actinic rays only from the opposite substrate 17 side, and the photosensitive resin composition 14 forming the layer 16 may be subjected to a curing reaction.

Next, referring to FIGS. 4 (a) and 4 (b), the reinforcing sheet 15, the layer 19 formed by the curing reaction of the photosensitive resin composition 14, and the laminated body 20 of the roughened sheet 1 are supported from the support. The substrate 11 and the counter substrate 17 are taken out and turned upside down and placed on the work table 21 with the reinforcing sheet 15 as the downside.

Then, as shown by the dashed-dotted arrow in FIG. 4 (b), the roughened sheet 1 is sequentially peeled from one end to the other end of the laminated body 20, and then transferred to the upper side of the layer 19 in the drawing. The roughened surface of the die surface 5 of the sheet 1 is formed into a roughened plate surface 22 to complete the original resin plate 23 for printing shown in FIG. 4 (c).

As the photosensitive resin composition 14, any of a variety of resin compositions can be used. The resin composition can be cured by irradiation with actinic rays such as ultraviolet rays, and has a suitable use after curing. For example, it has moderate flexibility or rubber elasticity in flexographic printing and the like, and can form a cured product having excellent solvent resistance to a solvent for cleaning a printing plate contained in ink used in printing.

The photosensitive resin composition is not limited to this, and examples thereof include a prepolymer having a 1,2-butadiene structure and having an ethylenic double bond at the terminal, an ethylenically unsaturated monomer, and Photopolymerization initiators and the like. As the photopolymerization initiator, benzoin alkyl ether is preferable.

In addition, as the reinforcing sheet 15, for example, thermoplastic resins such as polyethylene (PE), polypropylene (PP), TPU, PET, and tetrafluoroethylene x hexafluoropropylene copolymer (FEP) can be used. It is a sheet | seat which has transparency to actinic rays as mentioned above.

Thereafter, although not shown in the drawings, the four sides of the printing resin original plate 23 are cut to trim the overall planar shape into a rectangle, and the layers 19 near the two sides parallel to each other are thermally cut off by, for example, laser processing, and An unillustrated bite 24 for biting and holding by a vise of a printing press, or a chuck hole 25 for inserting a pin are formed, and then a predetermined printing pattern is formed on the plate surface 22 as necessary. This completes the flexographic printing plate 26 shown in FIG. 5.

In addition, in the illustration, the bite portion 24 is formed to have a constant width across the total width of the two sides of the flexographic printing plate 26 with a groove portion 27 having a constant width spaced from the plate surface 22. In addition, the chuck holes 25 are formed at a plurality of locations (five locations in the drawing) in the longitudinal direction of the bite portion 24 at equal intervals.

<The manufacturing method of a liquid crystal display element> This invention is the manufacturing method of the liquid crystal display element including the process which uses the flexographic printing plate manufactured by the said manufacturing method of this invention, and forms a liquid crystal alignment film by flexographic printing.

According to the present invention, it is possible to improve the productivity of a liquid crystal display element by using a flexographic printing plate having a small defect rate and excellent productivity using the roughened sheet of the present invention.

The other steps of the production method of the present invention can be carried out in the same manner as before. That is, a transparent electrode layer corresponding to a predetermined matrix pattern is formed on the surface of a transparent substrate such as a glass substrate, and then a liquid crystal alignment film is formed by flexographic printing using the flexographic printing plate, and then, if necessary, by friction or the like An alignment process is performed on the surface of the liquid crystal alignment film to produce a substrate.

Next, two substrates are prepared, and a liquid crystal material is sandwiched between the transparent electrode layers to form a laminate, and the polarizers are further provided on both outer sides of the laminate as necessary. To manufacture a liquid crystal display element. The configuration of the present invention is not limited to the illustrations described above.

For example, in the method for manufacturing a flexographic printing plate, a coating roll may be applied and extended by a roller having a roughened surface, instead of pressing the layer of the photosensitive resin composition toward the supporting substrate by facing the substrate. So that the thickness is made constant and the surface is roughened. In addition, various changes can be made in the range which does not deviate from the meaning of this invention. [Example]

<Example 1> (Roughened sheet) As the reinforcing film 2, a PET film having a thickness T2 of 0.05 mm was used, and as the thermoplastic elastomer for the intermediate layer 3, a propylene-based thermoplastic elastomer [manufactured by Mitsui Chemicals Co., Ltd.] was used. Tafmer PN-2060].

In addition, as the TPU for the surface layer 4, PANDEX T-1280N manufactured by DIC Covestro Polymer (stock), which is an ester-type TPU, was used. The thermoplastic elastomer and the TPU were respectively supplied to two extruders (not shown) connected to the manufacturing apparatus of FIG. 2, and the two layers of extrusion die 6 were laminated in a sheet shape and stacked on each other. The state is continuously extruded.

Then, before the laminated body of the extruded intermediate layer 3 and the surface layer 4 is cooled and solidified, the PET film (reinforcement film 2) continuously supplied in a long strip is continuously inserted into the roughened roller 7 and the opposite side. The surface layer 4, the intermediate layer 3, and the reinforcing film 2 are integrally laminated between the rollers 8, and the rough surface shape of the mold surface 10 of the roughened roller 7 is continuously transferred on the surface of the surface layer 4 so as to be continuous A roughened sheet 1 having a three-layer structure having a layer structure as shown in FIG. 1 is produced on the surface of which is a roughened mold surface 5.

As the roughened surface roller 7, the outermost layer 9 includes silicone rubber, and the outermost surface 9 is a model surface 10 of the outer peripheral surface thereof. The shape is measured based on a shape manufactured using KEYENCE (strand). The specific surface area obtained by measuring with a laser microscope VK-9510 was 3.9.

The thickness T3 of the intermediate layer 3 is set to 0.10 mm, and the thickness T4 of the surface layer 4 is set to 0.01 mm. The total thickness T1 of the roughened sheet 1 is 0.16 mm. When the specific surface area of the mold surface 5 of the roughened sheet 1 was measured using the shape measurement laser microscope, it was 3.3, and the transfer rate from the mold surface 10 was 84.6%.

(Flexographic printing plate) Using the roughened sheet 1, a resin original plate 23 for printing is produced through the steps of FIGS. 3 (a) to 3 (c) and FIGS. 4 (a) to 4 (c).

As a photosensitive resin composition to be a raw material of the resin original plate 23 for printing, NK resin manufactured by Sumitomo Rubber Industries, Ltd. was used. As the reinforcing sheet 15, a BF / CF bonding film manufactured by Sumitomo Rubber Industries, Ltd. was used.

Next, the four sides of the manufactured printing resin original plate 23 were cut to trim the overall planar shape into a rectangle, and then the layers 19 near the two sides parallel to each other were thermally cut off by laser processing to form the bite portions 24, The chuck hole 25 and the groove portion 27 produce a flexographic printing plate 26 shown in FIG. 5.

Laser processing conditions were set as follows: output of a carbon dioxide laser: 400 W × 2 beams, beam diameter: 20 μm, transmission pitch: 60 μm, transmission speed: 140 cm / sec. When the specific surface area of the plate surface 22 of the flexographic printing plate 26 was measured using the shape measurement laser microscope, it was 3.3, and the transfer rate from the mold surface 5 was 100%.

<Example 2> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.19 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.10 mm and the thickness T4 of the surface layer 4 to Except for 0.02 mm, a roughened sheet 1 having a three-layer structure was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a resin original plate 23 for printing was produced in the same manner as in Example 1, and Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.31 mm. The specific surface area of the mold surface 5 was 3.3, and the transfer rate from the mold surface 10 was 84.6%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.3, and the transfer rate from the die surface 5 was 100%.

<Example 3> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.10 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.13 mm and the thickness T4 of the surface layer 4 to Except for 0.02 mm, a roughened sheet 1 having a three-layer structure was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a resin original plate 23 for printing was produced in the same manner as in Example 1, and Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.25 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Example 4> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.13 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.07 mm and the thickness T4 of the surface layer 4 to With the exception of 0.05 mm, a roughened sheet 1 having a three-layer structure was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a resin original plate 23 for printing was produced in the same manner as in Example 1, and Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.25 mm. The specific surface area of the mold surface 5 was 3.3, and the transfer rate from the mold surface 10 was 84.6%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.3, and the transfer rate from the die surface 5 was 100%.

<Example 5> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.13 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.20 mm and the thickness T4 of the surface layer 4 to Except for 0.03 mm, a roughened sheet 1 having a three-layer structure was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a resin original plate 23 for printing was produced in the same manner as in Example 1, and Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.36 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Example 6> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.19 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.20 mm and the thickness T4 of the surface layer 4 to Except for 0.06 mm, a three-layer structured roughened sheet 1 was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a printing resin original plate 23 was produced in the same manner as in Example 1. Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.45 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Example 7> The thickness T2 of the PET film as the reinforcing film 2 was set to 0.04 mm, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.16 mm and the thickness T4 of the surface layer 4 to With the exception of 0.05 mm, a three-layer structured roughened sheet 1 was produced in the same manner as in Example 1, except that the roughened sheet 1 was used, and a resin original plate 23 for printing was produced in the same manner as in Example 1. Flexographic printing plate 26.

The total thickness T1 of the roughened sheet 1 is 0.25 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Comparative Example 1> Only the TPU for the surface layer 4 was extrusion-molded as a single layer, and was inserted between the roughened roll 7 and the counter roll 8 without laminating a PET film to produce a single-sided roughened sheet. A roughened sheet having a layer structure was manufactured in the same manner as in Example 1 except that the roughened sheet was used, and a flexographic printing plate 26 and a flexographic printing plate 26 were produced.

The roughened sheet has a total thickness of 0.25 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Comparative Example 2> The same as Example 1 except that the PET film was omitted, and the slit width of the die 6 was adjusted to set the thickness T3 of the intermediate layer 3 to 0.19 mm and the thickness T4 of the surface layer 4 to 0.07 mm. The roughened sheet having the two-layer structure of the intermediate layer 3 and the surface layer 4 was produced in the same manner. Except that the roughened sheet was used, a resin original plate 23 for printing and a flexographic printing plate 26 were produced in the same manner as in Example 1. .

The roughened sheet has a total thickness of 0.26 mm. The specific surface area of the mold surface 5 was 3.4, and the transfer rate from the mold surface 10 was 87.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 3.4, and the transfer rate from the die surface 5 was 100%.

<Comparative Example 3> Except that the thickness T2 of the PET film as the reinforcing film 2 was set to 0.19 mm, and the intermediate layer 3 was omitted and the surface layer 4 was directly laminated, the reinforcing film 2 and the reinforcing film 2 were produced in the same manner as in Example 1. The roughened sheet of the two-layer structure of the surface layer 4 was manufactured in the same manner as in Example 1 except that the roughened sheet was used, and a flexographic printing plate 26 and a flexographic printing plate 26 were produced. The thickness of the surface layer 4 was set to 0.01 mm.

The roughened sheet has a total thickness of 0.20 mm. The specific surface area of the mold surface 5 was 1.8, and the transfer rate from the mold surface 10 was 46.2%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 1.8, and the transfer rate from the die surface 5 was 100%.

<Comparative Example 4> Except that the thickness T2 of the PET film as the reinforcing film 2 was set to 0.13 mm, the intermediate layer 3 was omitted, and the surface layer 4 was directly laminated, except that the reinforcing film 2 was produced in the same manner as in Example 1. The roughened sheet of the two-layer structure of the surface layer 4 was manufactured in the same manner as in Example 1 except that the roughened sheet was used, and a flexographic printing plate 26 and a flexographic printing plate 26 were produced. The thickness of the surface layer 4 was set to 0.06 mm.

The roughened sheet has a total thickness of 0.19 mm. The specific surface area of the die surface 5 was 2.6, and the transfer rate from the die surface 10 was 66.7%. Furthermore, the specific surface area of the plate surface 22 of the flexographic printing plate 26 was 2.6, and the transfer rate from the die surface 5 was 100%.

<Formability Evaluation> In the step of producing the roughened sheet 1 of each of the examples and comparative examples, two types of molten resins that will be the raw materials of the intermediate layer 3 and the surface layer 4 were extruded through two layers by visual observation. The die 6 was continuously extruded in the form of a sheet and stacked on top of each other, and the state when the single-layer sheet was extruded in the case of a single layer, and the molding was evaluated based on the following criteria. Sex.

：: Continuous and uniform extrusion molding without uneven thickness or resin breakage in both layers. ○: Slight thickness unevenness was observed, but extrusion molding was continuous and almost uniform. (Triangle | delta): Although the site | part with uneven thickness was seen, it was continuously extruded. ×: Resin fracture occurred and continuous extrusion molding failed.

<Warpage Evaluation> After the roughened sheet 1 of each of Examples and Comparative Examples was produced, the presence or absence of warpage when placed on a flat plate was visually observed, and warpage was evaluated on the basis of the following criteria.

：: No warpage was observed at all. ○: Although slightly warped immediately after being placed on a flat plate, it was eliminated after being left to stand. (Triangle | delta): Although the curvature was seen, it was not completely eliminated after mounting on a flat plate and leaving it still, but the amount of curvature became small. ×: A large warpage was seen, and even if it was placed on a flat plate and left to stand, it was not completely eliminated.

<Rewindability Evaluation> The state when the long roughened sheet 1 before shearing produced in each of the examples and comparative examples was continuously wound into a roll shape with the die surface 5 as the outer side, The reelability was evaluated on the basis of the following criteria.

：: Continuous winding of 200 m or more without curling. ○: In a range of 100 m or more and less than 200 m, continuous winding can be performed without generating wrinkles. △: Within the range of 40 m or more and less than 100 m, continuous winding can be performed without generating wrinkles. ×: Curled wrinkles are generated in 40 m, and the productivity of the roughened sheet 1 is also affected.

<Evaluation of the number of fisheyes> The roughened sheets of each example and comparative example were observed, and the number of fisheyes per unit area (pieces / m ² ) was counted. Then, the number of fisheyes was evaluated on the following criteria.

：: The number of fish eyes is 0.05 or less / m ² . (Circle): The number of fish eyes exceeds 0.05 pieces / m ² and is 0.12 pieces / m ² or less. ×: The number of fish eyes exceeds 0.12 pieces / m ² .

<Evaluation of the number of bending defects> The number of bending defects per unit area (b / m ² ) of the bending defects generated after the roughened sheet of each of the examples and comparative examples is wound into a roll shape and then rolled back Count. Then, the bending defect was evaluated by the following criteria.

：: The number of bending defects is 0.05 or less / m ² . ○: The number of bending defects exceeds 0.05 / m ² and is 0.15 / m ² or less. Δ: The number of bending defects exceeds 0.20 pieces / m ² and is 0.30 pieces / m ² or less. ×: The number of bending defects exceeds 0.30 pieces / m ² .

<Transferability Evaluation> Based on the transfer ratio from the mold surface 10 to the mold surface 5, the transferability of the rough surface shape was evaluated on the following criteria.

○: The transfer rate is 80% or more. ×: The transfer rate is less than 80%.

<Comprehensive evaluation> All evaluations are only ◎ and ○, ◎, only one △ and others are ◎ or ○, ○, and two △ and others are ◎ or ○, △, except for this. The others were evaluated as ×. The above results are shown in Tables 1 and 2.

[Table 1]

[Table 2]

Based on the results of Examples 1 to 7 and Comparative Examples 1 to 4 in Tables 1 and 2, it was found that, in order to obtain a small amount of fish eyes and excellent moldability or rewindability, it is difficult to cause warping or bending. To fold a defective roughened sheet, it is necessary to form the roughened sheet into a reinforced film including a PET film, an intermediate layer including a thermoplastic elastomer having an affinity for the PET and TPU, and a surface layer including a TPU. This three-tier structure.

In addition, based on the results of Examples 1 to 7, it was found that if the effect is further improved, the thickness T4 of the surface layer is preferably 0.01 mm or more and 0.06 mm or less, and the thickness T3 of the intermediate layer is preferably 0.07 mm or more. 0.20 mm or less, and preferably the total thickness T1 of the roughened sheet is 0.45 mm or less, and the thickness T2 of the reinforcing film is 0.05 mm or more and 0.19 mm or less.

1‧‧‧ Roughened sheet
2‧‧‧ Enhanced Film
3‧‧‧ middle layer
4‧‧‧ surface
5‧‧‧ die face
6‧‧‧mould
7‧‧‧ Rough surface roller
8‧‧‧ pair of rollers
9‧‧‧ outermost
10‧‧‧ model surface
11‧‧‧ support substrate
12‧‧‧ surface
13‧‧‧ opposite
14‧‧‧ photosensitive resin composition
15‧‧‧ reinforced sheet
16‧‧‧ floors
17‧‧‧ Opposite substrate
18‧‧‧ opposite
19‧‧‧ floors
20‧‧‧Layer
21‧‧‧Workbench
22‧‧‧ surface
23‧‧‧Resin original for printing
24‧‧‧Bite into the Department
25‧‧‧Chuck hole
26‧‧‧ flexo printing
27‧‧‧Slot

FIG. 1 is an enlarged cross-sectional view showing an example of a layer structure of an embodiment of a roughened sheet according to the present invention. FIG. 2 is a diagram illustrating an example of a step of manufacturing the roughened sheet of the example shown in FIG. 1. FIGS. 3 (a) to 3 (c) are cross-sectional views illustrating an example of a process for manufacturing a printing resin original plate using the roughened sheet of the example in FIG. 1 by the manufacturing method of the present invention. 4 (a) to 4 (c) are cross-sectional views showing an example of subsequent steps of Figs. 3 (a) to 3 (c). 5 is a perspective view showing an example of a flexographic printing plate produced by the production method of the present invention using a printing resin original plate produced by the production method.

1‧‧‧ Roughened sheet

2‧‧‧ Enhanced Film

3‧‧‧ middle layer

4‧‧‧ surface

5‧‧‧ die face

Claims (8)

A roughened sheet is a roughened sheet used in the manufacture of a resin original plate for printing and includes: a reinforcing film; an intermediate layer provided on one side of the reinforcing film; and a surface layer provided on the surface. On the intermediate layer, a surface is formed as a roughened mold surface, the surface layer includes a urethane-based thermoplastic elastomer, the reinforcing film is a polyethylene terephthalate film, and the intermediate layer A thermoplastic elastomer having an affinity for the urethane-based thermoplastic elastomer and the polyethylene terephthalate is included. The roughened sheet according to item 1 of the scope of patent application, wherein the thermoplastic elastomer used as the raw material of the intermediate layer is selected from the group consisting of olefin-based thermoplastic elastomers, styrene-based thermoplastic elastomers, and polyester-based thermoplastic elastomers. And at least one of the group consisting of a polyamide-based thermoplastic elastomer. The roughened sheet according to item 1 or item 2 of the scope of patent application, wherein the thickness of the surface layer is 0.01 mm or more and 0.06 mm or less. The roughened sheet according to item 1 or item 2 of the patent application scope, wherein the thickness of the intermediate layer is 0.07 mm or more and 0.20 mm or less. The roughened sheet according to item 1 or 2 of the scope of patent application, wherein the total thickness of the roughened sheet is 0.45 mm or less, and the thickness of the reinforcing film is 0.05 mm or more and 0.19 mm the following. A method for manufacturing a resin original plate for printing, comprising the steps of: contacting a layer of a photosensitive resin composition with the roughened sheet according to any one of claims 1 to 5 of a patent application range; In the state of the mold surface, the rough surface shape of the mold surface is transferred to and from the layer by peeling the layer from the mold surface after performing a hardening reaction by irradiation with actinic rays. The surface in which the mold surface contacts, thereby forming the surface as a roughened plate surface. A method for manufacturing a flexographic printing plate includes the steps of: thermally cutting off a corresponding part of a printing resin original plate manufactured by using the method for manufacturing a printing resin original plate as described in item 6 of the patent application scope, and forming a portion for mounting. For the bite part of the printing press and the chuck hole. A method for manufacturing a liquid crystal display element includes the steps of forming a liquid crystal alignment film by flexographic printing using a flexographic printing plate manufactured using the flexographic printing plate manufacturing method described in item 7 of the scope of patent application.