JP2008207374A - Resin mold and manufacturing method of printing plate utilizing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technique for manufacturing a printing plate which can be well-adapted for highly detailed pattern printing. <P>SOLUTION: This mold has a photo-mask and a positive type photosensitive resin as its constitutional component. A printing plate is manufactured by employing a mold, which keeps the positive type photosensitive resin overlying the ultraviolet screening portion arranged in the photo-mask. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photosensitive resin mold and a method for producing a printing plate using the resin mold. More specifically, the present invention is used for producing a printing plate in which a plurality of fine concave portions are formed on the surface of a printing plate convex portion. The present invention relates to a resin mold and a method for producing a printing plate using the resin mold.

Conventionally, a photolithography method, which is relatively easy to achieve high definition, has been used to form a fine pattern such as a display panel or a printed wiring board. On the other hand, in recent years, low-cost and environmentally friendly printing methods have attracted attention because they have few expensive equipment and complicated processes, little process waste, and high material utilization efficiency.
Among the printing methods, in particular, the inkjet method does not damage the underlayer, and can draw a predetermined amount of functional ink such as conductive ink in a predetermined place. is there. On the other hand, when the pattern to be drawn becomes high definition, there are problems such as an increase in drawing time and clogging of fine nozzles.

The letterpress printing method is simpler than the inkjet method, and is a manufacturing method that is expected to shorten the printing time by batch printing and reduce the cost. However, the control of ink drawing amount (ink metering) and film thickness uniformity (marginal) (Suppression) has been considered difficult to improve.
In order to solve these problems, a predetermined amount of alignment film ink can be held on the convex portion by providing a plurality of fine protrusions or a lattice pattern on the surface of the convex portion of the printing plate in the alignment film printing of the liquid crystal panel. A technique that can significantly reduce the occurrence of a marginal phenomenon in which a portion swells is disclosed (for example, Patent Documents 1 to 3).
However, these techniques are disclosed for a technique for printing with a uniform film thickness on a relatively large area such as an alignment film, and are not adapted to high-definition pattern printing. The minute protrusions and the lattice pattern formed on the printing plate convex portion are relatively large, and are regions that can be created by the photolithography method used in the current flexographic printing plate manufacturing.

On the other hand, a nanoimprint method has been studied as a high-definition pattern creation method (for example, Non-Patent Document 1).
In the above method, a silicon substrate or glass substrate is processed by photolithography or electron beam method (EB processing), then a mold is formed by electroforming if necessary, and then the mold is press-bonded to a resin layer and cured. In this method, the fine shape of the mold is transferred to the resin layer by peeling.
The resin used is a photosensitive resin or a thermoplastic resin. Since the above method basically transfers the shape obtained by the silicon process and EB processing, processing on the order of several tens of nm becomes possible. However, although this process can easily obtain a high-definition pattern, the production of the mold is extremely expensive, the area that can be created is limited, and it is difficult to create shapes with different depths. There are still many challenges left.

On the other hand, a printing plate manufacturing method using a resin mold is also disclosed (for example, Patent Document 4).
The above method is a method of forming a resin mold by patterning a material opaque to ultraviolet rays on a substrate that transmits ultraviolet rays, laminating a negative photosensitive resin, and performing exposure and development from the transparent substrate side. It is. Next, the resin mold is filled with a curable silicone rubber, cured, and peeled to obtain a printing plate. A technique that uses the curved shape of a photosensitive black glass paste as a method for imparting the shape of the convex portion of the printing plate. It is difficult to give an arbitrary shape with high definition.

Japanese Patent No. 3376908 JP 2001-030644 A Japanese Patent Application No. 2006-170562 Japanese Patent No. 3705340 J. et al. Vac. Sci. Tech. , B14 (1966) p4129S. Y. Chou et al

  That is, an object of the present invention is to provide a mold for manufacturing a printing plate that can be applied to high-definition pattern printing and to provide a simple printing plate manufacturing method using the mold.

The present invention has been made to solve the above-described problems, and a printing plate capable of giving a high-definition shape by providing a plurality of fine concave portions on a convex portion in a relief printing plate is manufactured stably and inexpensively. The purpose is that.
That is, the present invention relates to a resin mold for producing a resin relief plate comprising a photomask and a positive photosensitive resin, and in particular, a photomask and a positive mold capable of imparting the shape of a plurality of fine recesses to the surface of a printing plate protrusion. The present invention relates to a mold made of a photosensitive resin, and relates to a method for producing a printing plate obtained using the resin mold.

That is, the present invention
1. A mold comprising a photomask and a positive photosensitive resin as constituent components, wherein a photocured positive photosensitive resin is laminated on an ultraviolet light shielding portion disposed in the photomask. Mold.
2. 1. The ultraviolet shielding portions of the photomask are circular or polygonal and are arranged. The mold described in 1.
3. (1) depositing a positive photosensitive resin on a photomask having an ultraviolet light shielding portion;
(2) a step of exposing from the photomask side;
(3) a step of developing after exposure;
Are manufactured in the order described above. Or 2. The mold described in 1.
4). (1) 1. Or 2. A step of filling a negative photosensitive resin on the photo-cured positive photosensitive resin of the mold according to 1.
(2) exposing from the photomask side of the mold and curing the negative photosensitive resin;
(3) a step of developing after exposure and subsequently peeling the cured negative photosensitive resin from the mold;
Are provided in the order described above, and relates to a method for producing a relief printing plate.

Unlike the conventional printing plate, the relief printing plate obtained in the present invention has regularly arranged fine recesses for replenishing ink on the projection surface, and the ink edge, which was a drawback of relief printing, is raised. The marginal phenomenon can be suppressed to a low level, and it is possible to solve the jaggedness and non-uniformity of the ink film thickness at the wiring edge, which is a problem particularly in the wiring field. Furthermore, the production method of the present invention is an extremely simple method that can form a plurality of fine concave portions on the surface of the convex portion and create the convex shape of the printing plate in a batch with the same photomask. That is, the printing plate convex portion is created by the photolithography method and the shapes of the plurality of fine concave portions on the convex portion surface are simultaneously given by the imprint method. In general, a positive resist has a high resolution, and a relief shape having a rectangular shape can give a plurality of fine concave shapes on a sharp convex surface.
Further, the release residue of the positive resin generated when the cured resin is peeled from the mold or the positive resin formed on the photomask can be easily removed by performing exposure and development processes.
Furthermore, it is possible to easily cope with changes in the shape of the multiple fine recesses formed on the surface of the protrusions for changing the shape of the print pattern and controlling the amount of ink applied by changing the design of the photomask. Of freedom.

Hereinafter, the present invention will be described in detail.
The mold of the present invention is a mold made of a photomask and a positive photosensitive resin. Conventionally, when such a resin mold is manufactured by a lithography method, it is usually obtained by applying a photosensitive resin as a molding material on a base substrate by lamination or coating, and exposing and developing through a mask. There are many cases. In contrast, the present invention is characterized in that a photomask is also used as a base substrate. That is, the positive photosensitive resin is directly applied to the photomask.

This photomask also functions as a photo-curing mask for a negative photosensitive resin filled in the mold. Therefore, it is essential that the photosensitive resin used as the mold material is a positive photosensitive resin, and a positive photosensitive resin with high resolution is preferable from the viewpoint of the fineness of the mold and the sharpness of the edges.
A commercially available liquid resin or solid resin can be used as the positive photosensitive resin that can be used in the present invention. High-sensitivity and high-resolution photoresist for lithography used in the semiconductor area when creating multiple fine concave shapes on the high-definition convex surface, for plating used in the MEMS area when creating deep surface shapes A high aspect thick film photoresist or the like may be used.

As will be described later, the mold of the present invention is also characterized by having a function of imparting the shape of a plurality of fine concave portions to the convex surface of the relief printing plate. Such a function can be obtained by using a photomask that serves as a light-shielding portion with a plurality of fine concave shapes provided on the convex surface of the relief printing plate.
For example, when creating a 2 μmφ cylindrical hole on the convex surface of a relief printing plate, a photomask in which a 2 μmφ black part (light-shielding part) is arranged at a desired position may be used. The depth of the cylinder is determined by the thickness of the positive photosensitive resin to be deposited. When it is desired to give a minute cylindrical shape, it is possible to easily create a shape of several μmφ by using a glass chrome mask. If a high resolution thick film positive photosensitive resin is used, the depth is several tens of μm. A resin mold for producing a cylindrical shape is obtained.

In order to produce a mold that also has the function of imparting the shape of a plurality of fine recesses to the convex surface of the relief printing plate as described above, the following production conditions may be used.
Specifically, referring to FIG. 1, first, a photomask (1) having an ultraviolet light shielding portion (2) is prepared, and a positive photosensitive resin (3) is deposited on the mask. At this time, the photomask to be used is not particularly limited, and a commercially available glass mask, a film mask or the like can be used, and by determining the shape and arrangement of the light-shielding portion according to the viscosity of the functional ink and the coating amount, A mold having a desired shape can be manufactured.
In addition, in order to adhere positive type photosensitive resin to the photomask reliably, it is coated with a commercially available adhesive (rubber, polyester, epoxy, acrylic, urethane, silane, etc.) having ultraviolet transparency. Various coating materials such as treatment, anchor treatment with a coupling agent, and hard coat (acrylic, etc.) can be used for the adhesive layer. In the sense of protecting the mask, a hard coat material or the like is preferably used.

The above-described photomask (a photomask having an adhesive layer if necessary) is coated with a positive photosensitive resin. The positive photosensitive resin is coated with a liquid material. Can be applied to form a film having a uniform thickness. The type of coater is not particularly limited as long as it can be a film having a uniform thickness, and a knife coater, a spin coater, a gravure coater, or the like can be used. Among these, a spin coater is preferable because it is easy to handle and can stably and uniformly control the film thickness.
The thickness of the positive photosensitive resin can be freely controlled by the viscosity of the liquid, the coating conditions of the coater, and the like.

The positive photosensitive resin applied under the above conditions is subsequently subjected to solvent removal and heat treatment.
The processing conditions differ depending on the type of positive photosensitive resin used. For example, in the case of a liquid resist used in the mounting field, after application and removal of the solvent at room temperature, 3 to 10 minutes at 80 to 120 degrees in the atmosphere. By performing the heat treatment, a positive photosensitive resin having a uniform film thickness can be deposited on the photomask.

The positive type photosensitive resin deposited on the mask is subsequently exposed and developed from the photomask side, so that other than the photosensitive resin directly under the mask light-shielding portion is removed. At this point, a mold (M) made of a positive photosensitive resin using a photomask as a base substrate is obtained (FIG. 1).
The development method employed in the present invention is not particularly limited, but dip development, shower development, and the like can be used.
In addition, what is necessary is just to perform exposure using the exposure machine generally used normally.

Next, the conditions for producing a relief printing plate using the mold obtained under the above production conditions will be described below with reference to FIG.
The obtained mold (M) is first filled with a negative photosensitive resin (4).
The negative photosensitive resin that can be used in the present invention is preferably a liquid resin because of its ease of filling. However, even if it is a solid resin, there is a problem as long as it has a low viscosity and can be filled into a resin mold. There is no. The negative photosensitive resin must be a solvent-resistant resin depending on the type of ink solvent used, and must satisfy practical characteristics such as dimensional stability and printing durability. As the negative photosensitive resin that satisfies such conditions, polyester-based, polyurethane-based, acrylate-based, polyamide-based, polyimide-based, and rubber-based compounds can be generally used.

In the present invention, if necessary, the resin mold (M) may be subjected to a mold release treatment to facilitate the peeling of the negative photosensitive resin (4) from the resin mold, thereby improving transferability. is there.
As the release treatment, commercially available silicon-based or Teflon (registered trademark) release agents are coated by dipping or spraying, or surface treatment by vapor deposition, CVD, or sputtering is applied.
The negative photosensitive resin (4) filled in the mold (M) as described above is exposed from the photomask (1) side to cure the negative photosensitive resin (4), and then peeled off to form a printing plate. (8)
Here, the method of filling the resin mold (M) with the negative photosensitive resin (4) is performed by applying the liquid resin from the mold (M) in the case of a liquid resin. In order to suppress it, it is preferable to perform a defoaming treatment such as vacuum defoaming or heating. In the case of a solid resin, it can be filled by bonding or the like, but it is effective to reduce the viscosity by heating in order to improve the filling property.

  On the other hand, in the exposure process, exposure may be performed using an exposure machine generally used from the photomask (1) side, as in the case of manufacturing the mold (M), but directly under the light shielding portion of the mask (1). Since it is also necessary to photo-cure the resin, it is possible to cure the printing plate convex part (6) as a whole by exposing it in a state of overexposure greater than the normal exposure amount. It is also effective to accelerate the crosslinking reaction by after-baking after exposure. Further, a substrate (5) having a high diffuse reflectance is bonded to the opposite side of the photomask (1), and the incident ultraviolet rays are reflected on the substrate (5) side, and the negative photosensitive resin (4) just below the mask light shielding portion (2). Can also be cured.

Moreover, in this invention, the uncured resin adhering to the printing plate after peeling can be removed by performing the finishing process which develops, rinses, and post-exposes the said printing plate as needed. It is also effective to perform post-exposure on the entire printing plate in order to complete the crosslinking reaction and increase the resin hardness. In this case, it is common to carry out under oxygen interruption.
In the above, the manufacturing method of the mold of this invention and the manufacturing method of a relief printing plate using the same were demonstrated.
Hereinafter, the present invention will be described in more detail with reference to FIGS. In addition, this invention is not restrict | limited by an Example.

[Example 1]
After applying a hard coat material (A-1964, acrylate) made by Tesque as an adhesive layer on a glass chrome mask (photomask) (1) having a thickness of 3 mm, a positive photosensitive resin (3) is applied. After drying and drying with a spin coater so that the thickness after drying becomes a predetermined thickness (film thickness) of three levels shown in Table 1, heat treatment was performed at 110 ° C. for 6 minutes. As the positive photosensitive resin (3), PMER (P-LA300PM) manufactured by Tokyo Ohka Co., Ltd. was used. Next, exposure and dip development were performed from the photomask (1) side using a parallel light exposure apparatus manufactured by Oak.
As a result, on the glass chrome mask (photomask) (1), the width of 5 to 15 μm, the interval of 5 to 15 μm, the height of 3 to 8 μm, and the projections of 1.5 to 5 μm mouths in each line are two rows. A resin mold (M) having a side-by-side structure was prepared (FIG. 1).
The shape of the photomask (1) used is line / space (L / S), and the light-transmitting part has a mouth-shaped light shielding part in two rows in the width direction and a constant interval in the length direction. It was. Table 1 shows the standard of the photomask (1) used and the resin film thickness of the manufactured mold (M).

After spraying this resin mold (M) with a release agent (solvent type) manufactured by Shin-Etsu Chemical Co., Ltd., a negative liquid photosensitive resin APR-G31 (polyester resin) (4) manufactured by Asahi Kasei Chemicals Co., Ltd. is formed to a thickness of 50 μm. After coating using an SRB apparatus, a 200 μm thick aluminum foil (5) made of Toyo Aluminum whose surface was sandblasted was lined. The diffuse reflectance on the aluminum foil surface was 64%. The exposure was performed at 1-8 j / cm ² with the AFP plate making system 910F from the glass mask (1) side of the resin mold (M). In addition, by using a substrate with high diffuse reflectance (in this case, sandblasted aluminum foil) (5), incident ultraviolet light is diffusely reflected on the surface of the backing substrate (5), and the resin directly under the mask light shielding portion (2) is cured. We were able to.

The cured resin is peeled off from the resin mold (M), washed with a 0.1 wt% sodium carbonate solution, post-exposed, and a plurality of predetermined openings (fine concave portions) on the surface of the convex portion (6) ( An L / S pattern printing plate (8) having 7) was obtained (FIG. 2). FIG. 3 shows an observation image with a laser microscope of the fine recesses (7) on the surface of the protrusions (6) of the printing plate (8).
The obtained printing plate (8) was attached to a precision relief printing machine manufactured by JEOL Ltd., and silver nano paste (9) manufactured by Harima Chemicals Co., Ltd. was printed on a glass substrate (FIG. 4). In addition, after printing, the silver nano paste was dried at 100 ° C. for 3 minutes, and the surface shape was observed with a laser microscope. The results are shown in Table 2.

  According to Table 2, the variation in the line width of the conductors was as small as ± 6% or less, and the edge portion showed good linearity. Further, the marginal phenomenon in which the edge of the transfer ink swells is hardly observed within the measurement range, and it has been proved that the printing plate has a high definition.

[Example 2]
After coating a Tesque hard coat material (A-1964, acrylate) on a PET silver salt mask (photomask) (1) having a thickness of 180 μm with a spin coater, a positive resist PMER (P- LA300PM) (3) was applied with a spin coater so as to have a predetermined thickness (= film thickness) as shown in Table 3, and air-dried, followed by heat treatment at 110 ° C. for 6 minutes. Next, exposure and dip development were performed from the photomask (1) side using a parallel light exposure apparatus manufactured by Oak.
As a result, on the PET mask (photomask) (1), the resin mold (M) having a protrusion of 20 to 60 μm in the line with a width of 50 to 150 μm, an interval of 50 to 150 μm, and a height of 20 to 40 μm, respectively. Created (FIG. 1).
The shape of the photomask (1) used is line / space (L / S), and there are two mouth-shaped light-shielding portions in the light transmission portion in the width direction and a constant interval in the length direction. Was used. Table 3 shows the standard of the used photomask (1) and the resin film thickness of the manufactured mold (M).

After spraying this resin mold (M) with a release agent (solvent type) manufactured by Shin-Etsu Chemical Co., Ltd., a negative liquid photosensitive resin APR-G31 (polyester resin) (4) manufactured by Asahi Kasei Chemicals Co., Ltd. is formed to a thickness of 100 μm. After applying using an SRB apparatus (blade coating apparatus), an aluminum foil (5) having a thickness of 200 μm made of Toyo Aluminum with a sandblast treatment applied to the surface was laminated. The diffuse reflectance on the aluminum foil surface was 72%. Exposure was performed from the PET mask (1) side at 6 to 12 j / cm ² with the AFP plate making system 910F.
The cured resin is peeled off from the resin mold (M), washed with a 0.1 wt% sodium carbonate solution, subjected to post-exposure, and an L / S pattern printing plate having a predetermined mouth shape opened on the surface of the convex portion (6) ( 8) was obtained (FIG. 2).
The obtained printing plate (8) was attached to a precision relief printing machine manufactured by JEOL Ltd., and silver nanopaste manufactured by Harima Kasei Co., Ltd. was printed on a glass substrate (FIG. 4). In addition, after printing, the silver nano paste (9) was dried at 100 ° C. for 3 minutes, and the surface shape was observed with a laser microscope. The results are shown in Table 4.

  As apparent from Table 4, the variation in the line width of the conductors was as small as about ± 7%, and the edge portion showed good linearity. Moreover, almost no marginal phenomenon was observed within the measurement range.

[Example 3]
Asahi Kasei Chemicals Co., Ltd. plate-like photosensitive resin AFP-SH (rubber-based resin) coated with an adhesive containing a thermoplastic elastomer coated with an aluminum support having a thickness of 200 μm and a polyamide layer having a thickness of 4 μm The film was sandwiched between 100 μm polyester protective films having a thickness of 50 μm, and pressed at 130 ° C. and 20 Mpa for 4 minutes to obtain a photosensitive resin solid plate.
In the same manner as in Example 1, a glass chrome mask (photomask) (1) having a thickness of 3 mm was used. After the adhesive layer was coated, a resin mold (M) was formed with a positive photosensitive resin (3). The photomask (1) used was designed in Example 2.
, No. 3 is the same.

After the resin mold (M) is treated with a release agent, the above photosensitive resin solid plate is thermally laminated at 110 ° C., 10 KPa, 50 cm / min, and the photosensitive resin solid plate is applied to the resin mold (M). Filled.
Exposure is performed from 5 to 16 j / cm ² with the AFP plate making system 910F from the glass mask (photomask) (1) side of the resin mold (M), and by using a substrate (5) having a high diffuse reflectance as in Example 1. The resin directly under the mask light shielding part (2) could be cured.

The cured resin is peeled from the resin mold (M), washed with a high-boiling solvent FLEXLIGHT SOLVITt for Daiso Chemical Co., Ltd. flexographic plate making, post-exposed, and a plurality of openings having a 60 μm mouth shape opened on the surface of the convex portion (6). A printing plate (8) having fine recesses (7) (L / S = 150/150 μm) was obtained (FIG. 2).
The obtained printing plate (8) was attached to a precision relief printing machine manufactured by JEOL Ltd., and silver nano paste (9) manufactured by Harima Kasei Co., Ltd. was printed on a glass substrate. After printing, the silver nano paste was dried at 100 ° C. for 3 minutes, and the surface shape was observed with a laser microscope. As a result, L / S = 145/155 μm, and the variation in the line width of the conductors was ± 6% or less. The edge portion showed good linearity. Moreover, the marginal phenomenon was hardly recognized within the measurement range.

  When the mold of the present invention is used, a printing plate that can be applied to high-definition pattern printing can be manufactured by a simple method and at a low cost, which greatly contributes to high definition of display panels and printed wiring boards. It becomes possible.

It is the schematic showing the manufacturing process of the mold of this invention. It is the schematic showing the manufacturing process of the relief printing plate of this invention. It is a figure showing the observation image of the laser microscope of the printing plate manufactured when the present Example 1 (when a mouth-shaped recessed part is produced 5 rows). It is the schematic explaining the process printed using the printing plate manufactured by this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Photomask 2 Ultraviolet light shielding part 3 Positive type photosensitive resin 4 Negative photosensitive resin 5 A board | substrate with a high diffuse reflectance 6 Convex part of a printing plate 7 Plural fine recessed part 8 Printing plate 9 Silver nano paste M Resin mold

Claims (4)

  A mold comprising a photomask and a positive photosensitive resin as constituent components, wherein a photocured positive photosensitive resin is laminated on an ultraviolet light shielding portion disposed in the photomask. Mold.   The mold according to claim 1, wherein the ultraviolet light shielding portions of the photomask are circular or polygonal and arranged. (1) depositing a positive photosensitive resin on a photomask having an ultraviolet light shielding portion;
(2) a step of exposing from the photomask side;
(3) a step of developing after exposure;
The mold according to claim 1 or 2, wherein the molds are manufactured in the order described above. (1) A step of filling a negative photosensitive resin onto the photocured positive photosensitive resin of the mold according to claim 1 or 2,
(2) exposing from the photomask side of the mold and curing the negative photosensitive resin;
(3) a step of developing after exposure and subsequently peeling the cured negative photosensitive resin from the mold;
Are applied in the order described above, a method for producing a relief printing plate.

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