JP2011235517A - Method of producing mold sheet and mold sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of producing a mold sheet which continuously producing a mold sheet.SOLUTION: The method of producing mold sheet includes steps of: preparing a feed roller onto which a substrate is wound and an embossing roller (S1); unwinding the substrate from the feed roller and conveying the substrate to the embossing roller; then, forming an uncured layer made of a silicone composition between the substrate and the embossing roller to hold the uncured layer between the substrate and the embossing roller (S2); heating the embossing roller, at the same time, rotating the roller, transferring a plurality of embossing patterns onto the surface of the uncured layer and, at the same time, thermosetting the uncured layer (S3); and stripping the substrate on which the thermoset uncured layer is formed from the embossing roller, thereafter, further thermosetting the uncured layer to form a silicone layer (S4).

Description

  The present invention relates to a mold sheet manufacturing method and a mold sheet, and more particularly to a mold sheet manufacturing method having a plurality of embossed patterns and a mold sheet.

  Soft lithography has been proposed as a technique for transferring a fine pattern. In soft lithography, pattern transfer is performed using a resin mold (also called a stamp) having an embossed pattern on the surface. More specifically, ink is applied to the emboss pattern of the resin mold. Pattern transfer is performed by bringing the embossed pattern coated with ink into contact with the substrate.

  Japanese Unexamined Patent Publication No. 2009-292150 (Patent Document 1) discloses a method for manufacturing an organic mold. Specifically, the resin composition is coated on the pattern surface of the flat master mold. Next, the resin composition is irradiated with active energy rays to cure the resin composition, thereby forming an organic mold.

JP 2009-292150 A JP 2009-51085 A JP 2009-205876 A

  The method for producing an organic mold disclosed in Patent Document 1 is a batch process using a flat master mold and cannot produce a mold continuously.

  The objective of this invention is providing the manufacturing method of the mold sheet which can be produced continuously.

Means and effects for solving the problems

  The mold sheet manufacturing method according to the present invention includes a preparing step, a sandwiching step, a thermosetting step, and a forming step. In the step of preparing, a base material having flexibility and an embossing roll are prepared. In the sandwiching step, an uncured layer made of the silicone composition is formed between the substrate and the embossing roll, and the uncured layer is sandwiched between the substrate and the embossing roll. The heat curing step rotates while heating the embossing roll, and heat cures the uncured layer while transferring a plurality of emboss patterns to the surface of the uncured layer. In the forming step, the base material on which the heat-cured uncured layer is formed is peeled off from the embossing roll, and then the heat-cured uncured layer is further thermally cured to form a silicone layer.

  In the method for producing a mold sheet according to the present invention, the mold sheet is produced using an embossing roll. Therefore, a mold sheet can be manufactured continuously. Furthermore, in the method for producing a mold sheet according to the present invention, the uncured layer is subjected to two or more stages of heat treatment. More specifically, when the uncured layer is sandwiched between the embossing roll and the substrate, the uncured layer is thermally cured. Then, after leaving the embossing roll, the uncured layer is further thermally cured by heat treatment. Through the above steps, the dimensional accuracy of the emboss pattern of the mold sheet is improved.

  The mold sheet by this invention is equipped with a base material and a silicone layer. The substrate has flexibility and heat resistance. The silicone layer is formed on the substrate. The silicone layer is an addition reaction type and has a main surface on which a plurality of emboss patterns are formed.

  According to the present invention, the layer having the embossed pattern is an addition reaction type silicone layer. The shrinkage rate when the addition reaction type silicone layer is cured is smaller than the shrinkage rate when the ultraviolet curable resin is cured. Therefore, it is easy to obtain an emboss pattern with high dimensional accuracy as compared with the ultraviolet curable resin.

  Furthermore, the substrate has flexibility and heat resistance. Therefore, when manufactured by the above-described manufacturing method, the substrate can withstand heat and can be curved along the surface of the roll.

It is sectional drawing of the mold sheet by embodiment of this invention. It is a manufacturing apparatus of the mold sheet shown in FIG. It is a perspective view of the embossing roll in FIG. It is a flowchart which shows the manufacturing method of the mold sheet shown in FIG. It is a figure which shows the relationship between the surface temperature of the embossing roll in the thermosetting process shown in FIG. 3, and the time which a thermosetting process requires.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

[Configuration of mold sheet]
The mold sheet according to the present embodiment is used for soft lithography, for example. FIG. 1 is a cross-sectional view of the mold sheet 1. With reference to FIG. 1, the mold sheet 1 is a sheet form or a film form. The mold sheet 1 includes a base material 10 and a silicone layer 11. The mold sheet 1 further includes an adhesive layer 12.

  The substrate 10 is made of a resin having flexibility and heat resistance. Preferably, the temperature index (Thermal Index: TI) based on IEC (International Electrotechnical Commission) 216 of the substrate 10 exceeds 120 ° C. The temperature index here is the temperature at which the tensile strength is halved when placed under that temperature for 20,000 hours. Examples of the resin of the base material 10 include polyethylene naphthalate (PEN), polyimide (PI), polyetherimide (PEI), polyethersulfone (PES), polyphenylene sulfide (PPS), polycarbonate (PC), and polyamideimide (PAI). ), PEEK (polyetherketone) and cycloolefin resin (COP).

  The silicone layer 11 is formed on the substrate 10 via the adhesive layer 12. The silicone layer 11 has a surface 111. On the surface 111, an emboss pattern is formed. The emboss pattern has a plurality of convex portions 111A. The height L1 of the convex portion 111A is 10 nm to 500 μm. The height L1 is obtained by the following method. The height of 20 arbitrary convex parts 111A is measured, and the average of the measured heights of the 20 convex parts 111A is defined as the height L1 of the embossed pattern.

  The silicone layer 11 is an addition reaction type. That is, the silicone layer 11 is formed by curing the silicone composition with heat. The addition reaction type silicone composition is a well-known composition. The addition reaction type silicone composition contains, for example, a polyorganosiloxane containing an alkenyl group, a polyorganosiloxane containing a hydrosilyl group (polyorganohydrogensiloxane) and a platinum catalyst. The polyorganosiloxane is, for example, polydimethylsiloxane (PDMS).

  The silicone layer 11 has excellent releasability because of its low affinity with organic polymers. Therefore, the silicone layer 11 is suitable for use as a mold. The silicone layer 11 is further excellent in heat resistance, self-adhesiveness, and flexibility.

  The adhesive layer 12 is disposed between the base material 10 and the silicone layer 11. The lower surface of the adhesive layer 12 is in contact with the substrate 10, and the upper surface is in contact with the silicone layer 11. The adhesive layer 12 improves the adhesion of the silicone layer 11 to the substrate 10.

  The adhesive layer 12 is, for example, a silane coupling agent. The silane coupling agent has a hydrolyzable group and an organic functional group, and bonds the substrate 10 and the silicone layer 11 firmly. The thickness L2 of the adhesive layer 12 is 1 nm to 1000 nm, preferably 50 to 500 nm.

  The mold sheet 1 having the above configuration can be used in various fields. For example, the mold sheet 1 is used for soft lithography. As described above, the silicone layer 11 has excellent releasability. When ink is applied to the embossed pattern of the silicone layer 11 and the embossed pattern is brought into contact with the substrate, the ink in the contacted part is easily separated from the silicone layer 11 and transferred to the substrate. Therefore, the mold sheet 1 is suitable for use in soft lithography.

  The mold sheet 1 can also be used as a mold for manufacturing various optical sheets such as a microlens array, a prism sheet, and a lenticular lens sheet.

  A mold sheet 1 shown in FIG. 1 includes an adhesive layer 12. However, the mold sheet 1 according to the present embodiment may not include the adhesive layer 12.

[Mold sheet manufacturing method]
FIG. 2 is a configuration diagram of a manufacturing apparatus 100 used in the method for manufacturing the mold sheet 1 according to the present embodiment. With reference to FIG. 2, the mold sheet 1 is manufactured by a roll-to-roll method using a manufacturing apparatus 100. The manufacturing apparatus 100 includes a supply roll 101, an embossing roll 102, a coating apparatus 103, and a winding roll 105.

  A base material 10 is wound around the supply roll 101. The coating device 103 is disposed between the supply roll 101 and the embossing roll 102. The coating device 103 applies an uncured silicone composition between the base material 10 and the embossing roll 102 to form an uncured layer between the base material 10 and the embossing roll 102. When the uncured layer is thermally cured, the silicone layer 11 is formed.

  The embossing roll 102 is disposed between the supply roll 101 and the take-up roll 105. FIG. 3 is a perspective view of the embossing roll 102. Referring to FIG. 3, an emboss pattern 102 </ b> A corresponding to the emboss pattern of mold sheet 1 is formed on the surface of emboss roll 102. When the mold sheet 1 is manufactured, the surface of the embossing roll 102 is heated to 100 ° C. or higher. The embossing roll 102 transfers the embossed pattern to the uncured layer and thermally cures the uncured layer (first thermosetting step).

  The manufacturing apparatus 100 further includes a thermal curing device 104. The thermal curing device 104 is disposed between the embossing roll 102 and the take-up roll 105. The thermal curing device 104 heat-treats the uncured layer separated from the embossing roll 102 and further thermally cures the uncured layer (second thermosetting step). The mold sheet 1 is manufactured through the above steps. The take-up roll 105 takes up the manufactured mold sheet 1.

  As described above, in the method for manufacturing the mold sheet 1 according to the present embodiment, the mold sheet 1 is continuously manufactured by the roll-to-roll method using the embossing roll 102. Therefore, the productivity of the mold sheet 1 can be improved.

  Further, the uncured layer formed on the substrate 10 is further thermally cured by the thermal curing device 104 after being thermally cured by the embossing roll 102. Thus, the productivity of the mold sheet 1 is further improved by thermosetting the uncured layer in two stages. Furthermore, the dimensional accuracy of the emboss pattern of the silicone layer 11 can be improved.

  A method for manufacturing the mold sheet 1 using the manufacturing apparatus 100 shown in FIG. 2 will be described in detail. FIG. 4 is a flowchart of the method for manufacturing the mold sheet 1. Referring to FIG. 4, first, supply roll 101 and embossing roll 102 are prepared (S1). As described above, the base material 10 is wound around the supply roll 101. An adhesive layer 12 may be formed on the base material 10 wound around the supply roll 101. The method for forming the adhesive layer 12 on the substrate 10 is as follows. On the base material 10 before being wound around the supply roll 101, the coating liquid is applied by a coating device such as a die coater to form the adhesive layer 12. After the adhesive layer 12 is formed, the base material 10 is wound around the supply roll 101.

  The base material 10 has at least flexibility that can be wound around the supply roll 101 and the winding roll 105. Therefore, the base material 10 can be wound around the supply roll 101.

  The prepared supply roll 101 and embossing roll 102 are arranged in the manufacturing apparatus 100. Then, the base material 10 is sent out from the supply roll 10. As shown in FIG. 2, a plurality of transport rolls 200 are arranged between the supply roll 101 and the embossing roll 102. The base material 10 sent out from the supply roll 101 is transported in the direction of the embossing roll 102 via the plurality of transport rolls 200. A nip roll 250 is disposed in front of the embossing roll 102. The substrate 10 passes between the embossing roll 102 and the nip roll 250.

  The applicator 103 applies the uncured silicone composition 103A between the surface of the substrate 10 disposed between the nip roll 250 and the embossing roll 102 and the surface of the embossing roll 102 (S2). The applied silicone composition 103A is sandwiched between the base material 10 and the embossing roll 102 to form an uncured layer having a certain thickness.

  The embossing roll 102 rotates in the direction of the arrow ARW1. The uncured layer formed on the substrate 10 is conveyed in the direction in which the take-up roll 103 is disposed as the embossing roll 102 rotates while being sandwiched between the substrate 10 and the embossing roll 102. At this time, the emboss pattern is transferred to the surface of the uncured layer by the emboss pattern 102A of the emboss roll 102.

  As described above, the embossing roll 102 rotates while being heated. Therefore, the embossing roll 102 transfers the embossed pattern to the uncured layer and thermally cures the uncured layer (S3: first thermosetting step).

  As described above, the surface temperature of the embossing roll 102 is 100 ° C. or higher. FIG. 5 shows the surface temperature of the embossing roll 102 and the time required until the silicone composition is thermally cured to form the silicone layer 11. The addition reaction type silicone composition takes a longer time to complete the curing than the ultraviolet curing type silicone composition. Referring to FIG. 5, for example, when the surface temperature of embossing roll 102 is 100 ° C. or higher, the time required for the silicone composition to cure and form silicone layer 11 is 5 minutes or longer. When the surface temperature of the embossing roll 102 is 120 ° C. or higher, the time required for thermosetting is 1 minute or longer. When the surface temperature of the embossing roll 102 is 150 ° C. or higher, the time required for thermosetting is 15 seconds or longer.

  Therefore, the preferable surface temperature of the embossing roll 102 is 120 ° C. or higher, and more preferably 150 ° C. or higher.

In the first thermosetting step (S3), the substrate 10 receives heat from the embossing roll 102 through the uncured layer. Therefore, the base material 10 is required to have high heat resistance. Therefore, the base material 10 has heat resistance. Preferably, as described above, the temperature index (Thermal Index: TI) based on IEC (International Electrotechnical Commission) 216 of the resin contained in the substrate 10 exceeds 120 ° C.
In the first thermosetting step, the heat is gradually cured from the surface of the uncured layer in contact with the surface of the embossing roll 102. As described above, it takes time until the uncured layer is thermally cured to become the silicone layer 11. When the silicone layer 11 is completed while the uncured layer is in contact with the embossing roll 102, it takes time to manufacture and the productivity is reduced.
Therefore, in the present embodiment, the base material 10 on which the uncured layer is formed is peeled off from the embossing roll 102 before the curing of the uncured layer is completed. Hereinafter, the base material 10 on which an uncured layer that has not been cured is formed is referred to as an “intermediate sheet”. At least the surface portion of the uncured layer on the intermediate sheet is cured. Therefore, the uncured layer can keep its shape.

  The manufacturing apparatus 100 conveys the intermediate sheet by the conveyance roll 200 and inserts it into the thermal curing apparatus 104. The thermal curing device 104 heats the intermediate sheet. Specifically, the intermediate sheet is heated at 100 ° C to 180 ° C. As a result, the uncured layer is further thermally cured (S4: second thermosetting step). The uncured layer of the intermediate sheet is thermally cured in the thermal curing device 104 to become the silicone layer 11.

  As described above, an uncured layer formed on the substrate 10 is thermally cured stepwise by providing the second thermosetting process in the thermal curing device 104 in the subsequent process of the embossing roll 102. In the present embodiment, it is not necessary to complete the silicone layer 11 while the uncured layer is in contact with the embossing roll 102. Therefore, it can suppress that productivity falls by a 1st thermosetting process (S3).

  A method of providing a heat curing device in front of the embossing roll 102 and thermally curing the uncured layer before contacting the embossing roll 102 to some extent is also conceivable. However, when this method is employed, the uncured layer whose surface is cured comes into contact with the surface of the embossing roll 102. Therefore, it becomes difficult to fill the uncured layer into the embossed pattern 102A of the embossing roll 102, and the accuracy of pattern transfer decreases. As a result, the dimensional accuracy of the emboss pattern of the silicone layer 11 decreases. Furthermore, in the uncured layer, bubbles in the portion filled in the emboss pattern 102A of the embossing roll 102 are difficult to escape, so bubbles easily remain in the silicone layer 11. Further, since the uncured layer becomes the silicone layer 11 and the mold sheet 1 is completed while being in contact with the embossing roll 102, the mold sheet 1 is hardly peeled off from the embossing roll 102.

  On the other hand, in this embodiment, heat curing by the thermal curing device 104 is not performed before the uncured layer contacts the embossing roll 102, and the heat curing device 104 is performed after the uncured layer leaves the embossing roll 102. Perform heat curing. In this case, since the uncured layer in contact with the embossing roll 102 is not thermally cured, the silicone composition constituting the uncured layer is easily filled in the embossing pattern 102 </ b> A of the embossing roll 102. Furthermore, bubbles in the silicone composition are easily removed. Therefore, the accuracy of pattern transfer is improved, and the dimensional accuracy of the emboss pattern of the silicone layer 11 is improved.

  Further, when peeled from the embossing roll 102, the uncured layer is not completely cured. Therefore, the intermediate sheet including the uncured layer is easily peeled off from the embossing roll 102.

  In the thermal curing device 104, the uncured layer is thermally cured to become the silicone layer 11, and the mold sheet 1 is completed. The manufactured mold sheet 1 exits the thermal curing device 104 and is wound on the winding roll 105 (S5). Since the wound mold sheet 1 is thermally cured in step S4, the embossed pattern can be prevented from collapsing.

  As described above, the mold sheet 1 can be continuously manufactured by the roll-to-roll method using the manufacturing apparatus 100. Therefore, productivity is improved. Further, the uncured layer is thermally cured stepwise by the embossing roll 102 and the thermal curing device 104 in the subsequent process, thereby completing the silicone layer 11. Therefore, the transfer accuracy with the embossing roll 102 is improved, and an emboss pattern with high dimensional accuracy is obtained. Furthermore, the embossing roll 102 does not complete the mold sheet 1, and the embossing roll 102 produces an intermediate sheet. Since the thermosetting of the uncured layer of the intermediate sheet is not completed, the intermediate sheet can be easily peeled off from the embossing roll 102, and the occurrence of defects in the embossed pattern can be suppressed.

  In the present embodiment, the silicone layer 11 is formed using an addition reaction type silicone composition. The ultraviolet curable silicone composition shrinks by about 10% when cured. Therefore, it is difficult to obtain an emboss pattern with high dimensional accuracy. In contrast, the shrinkage rate when the addition reaction type silicone composition is thermally cured is less than 1%. Therefore, in this embodiment, an emboss pattern with high dimensional accuracy can be obtained.

[Other embodiments]
In the method for manufacturing the mold sheet 1 described above, the mold sheet 1 is wound around the winding roll 105 (S5), and the manufacturing ends. However, the silicone sheet 11 may be formed by shortening the staying time of the intermediate sheet in the thermal curing device 104 and winding the intermediate sheet on the winding roll 105 and then further heating the winding roll 105. For example, the take-up roll 105 that has wound up the intermediate sheet is charged into a batch furnace installed off-line. Then, the take-up roll 105 may be heated for a predetermined time in a batch furnace to form the silicone layer 11.

  A mold sheet 1 was manufactured by a roll-to-roll method using the manufacturing apparatus described above. A PEN film (trade name Q51 manufactured by Teijin Ltd.) was used as the substrate 10. Using a die coater, the coating solution was applied onto the PEN film to form an adhesive layer. The product name “1200OS” manufactured by Toray Dow Corning Co., Ltd. was used as the coating solution. After the adhesive layer was formed, the PEN film was wound up on a supply roll.

  Subsequently, the PEN film was sent out from the supply roll, and an uncured layer was formed on the PEN film using a die coater. The silicone composition constituting the uncured layer was a PDMS prepolymer. The PDMS prepolymer comprises 87% by weight of silicone elastomer (trade name Sylgard 184: manufactured by Toray Dow Corning Co., Ltd.), 8.7% by weight of catalyst, and dimethylpolysiloxane (trade name: SH 200 FRUID 20 CS) 4.3. Contains% by weight. The surface temperature of the embossing roll was 150 ° C., and the furnace temperature of the thermal curing device 104 was 150 ° C. By the above manufacturing method, the uncured layer was thermally cured stepwise, and the mold sheet 1 could be manufactured.

DESCRIPTION OF SYMBOLS 1 Mold sheet 10 Base material 11 Silicone layer 111 Surface 111A Convex part 12 Adhesive layer 102 Embossing roll 102A Embossing pattern 105 Winding roll L1 Height of convex part

Claims (7)

Preparing a flexible substrate and an embossing roll;
Forming an uncured layer made of a silicone composition between the substrate and the embossing roll, and sandwiching the uncured layer between the substrate and the embossing roll;
Rotating while heating the embossing roll, and thermally curing the uncured layer while transferring a plurality of embossed patterns to the surface of the uncured layer;
After the base material on which the heat-cured uncured layer is formed is peeled off from the embossing roll, the mold sheet includes a step of further thermally curing the uncured layer by heat treatment to form a silicone layer. Method. It is a manufacturing method of the mold sheet according to claim 1,
The base material is made of a resin having a temperature index based on IEC216 exceeding 120 ° C.,
The surface temperature of the said embossing roll is a manufacturing method of a mold sheet higher than 100 degreeC. The method for producing a mold sheet according to claim 1 or 2, further comprising:
The manufacturing method of a mold sheet provided with the process of winding up the said mold sheet provided with the said silicone layer and the said base material on a winding roll. A base material having heat resistance and flexibility;
A mold sheet comprising: an addition reaction type silicone layer formed on the substrate and having a surface on which a plurality of embossed patterns are formed. The mold sheet according to claim 4,
The said base material is a mold sheet which consists of resin with a temperature index based on IEC216 exceeding 120 degreeC. The mold sheet according to claim 4,
The embossed pattern has a height of 10 nm to 500 μm. It is a mold sheet given in any 1 paragraph of Claims 4-6,
The silicone layer is formed by bringing a heated embossing roll into contact with a non-cured layer made of a silicone composition to thermally cure, and further thermally curing the uncured layer separated from the embossing roll. Sheet.

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