Gauze stretching and adhesion method

Abstract

To prevent positional deviation and boundary peeling of a polyolefin-based hot-melt adhesive even when tension is applied to gauze.SOLUTION: A gauze stretching and adhesion method includes: by using an adhesive sheet generation apparatus 1 including a compressed air inlet 2, a relief valve 3, a silicon heater 4, a cylinder 5, an adjustment valve 6, a connection screw portion 7, and a mold 10, placing, on a frame body F in screen printing, a polyolefin-based hot-melt adhesive (adhesive sheets S1 to S4) formed in a sheet shape; and heating the frame body F together with the polyolefin-based hot-melt adhesive (adhesive sheets S1 to S4) at a predetermined temperature.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a gauze stretching and bonding method that prevents displacement of the adhesive and boundary peeling even when tension is applied to the gauze. [Background technology]

[0002] Generally, screen printing plates are made by moving a gauze and a thermal head relative to each other and using the thermal head to heat and perforate the gauze, and are widely used because of their simple structure and easy plate-making process.

[0003] Here, the gauze is also called a heat-sensitive screen plate, and it is necessary to properly stretch the gauze on the frame.

[0004] Patent Document 1 discloses a technology for forming a coating film of adhesive approximately 2 mm thick, characterized by applying a silane coupling agent to the surface of a frame made of aluminum material, performing a base preparation treatment, applying and heating an adhesive, baking the adhesive onto the surface of the frame, and then heating and pressing a gauze stretched under a certain tension onto the surface of the frame, thereby attaching the gauze to the surface of the frame. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2000-25195 Summary of the Invention [Problem to be solved by the invention]

[0006] However, in the technology of Patent Document 1, an adhesive is applied to the surface of a frame made of aluminum, heated, and baked onto the surface of the frame, and a gauze stretched under a certain tension on the surface of the frame is then heated and pressed, so that tension on the gauze can cause the adhesive to shift position.Furthermore, after heat welding, releasing the tension of the gauze stretcher can cause boundary peeling between the frame and the adhesive, making it difficult to properly stretch the gauze on the surface of the frame.

[0007] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a gauze stretching and bonding method that prevents the adhesive from shifting in position and boundary peeling even when tension is applied to the gauze. [Means for solving the problem]

[0008] In order to achieve the above object, the first feature of the gauze stretching and bonding method according to the present invention is as follows: A sheet of polyolefin-based hot melt adhesive is placed on a plate-making frame for screen printing, and the plate-making frame is heated together with the polyolefin-based hot melt adhesive at a predetermined temperature. [Effects of the Invention]

[0009] According to the gauze stretching and bonding method of the present invention, it is possible to prevent the adhesive from shifting in position and boundary peeling even when tension is applied to the gauze. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic view of an adhesive sheet producing apparatus according to a first embodiment of the present invention. [Figure 2] 1A and 1B are diagrams showing a mold provided in an adhesive sheet producing apparatus according to a first embodiment of the present invention, where (a) is a plan view of the mold and (b) is a cross-sectional view of the mold. [Figure 3] 1A is a perspective view of a frame on which an adhesive sheet is placed, and FIG. 1B is a cross-sectional view of the frame on which the adhesive sheet is placed. [Figure 4]The figure shows the gauze stretched over the frame under a constant tension. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same or equivalent parts and components are designated by the same or equivalent reference numerals throughout the drawings. However, it should be noted that the drawings are schematic and may differ from the actual product. Furthermore, the drawings may include parts with different dimensional relationships and ratios. Furthermore, the embodiments shown below are merely examples of devices and the like that embody the technical concept of this invention, and the technical concept of this invention does not limit the arrangement of each component to that shown below. Various modifications can be made to the technical concept of this invention within the scope of the claims.

[0012] Fig. 1 is a schematic diagram of an adhesive sheet producing apparatus according to a first embodiment of the present invention, and Fig. 2 is a diagram showing a mold provided in the adhesive sheet producing apparatus according to the first embodiment of the present invention. Fig. 2(a) is a plan view of the mold, and Fig. 2(b) is a cross-sectional view of the mold.

[0013] As shown in FIG. 1, the adhesive sheet generating apparatus 1 according to the first embodiment of the present invention has a compressed air inlet 2, a relief valve 3, a silicon heater 4, a cylinder 5, an adjustment valve 6, a connecting screw portion 7, and a mold 10.

[0014] By connecting the connecting screw part 7 and the mold 10, the hot melt adhesive stored in the cylinder 5 and heated to a predetermined temperature by the silicon heater 4 is injected from the cylinder 5 into the mold 10. During injection, the injection speed and amount are adjusted by the adjustment valve 6.

[0015] The hot melt adhesive is made of a polyolefin-based material and is injected into a cylinder 5 through a relief valve 3. A predetermined amount of compressed air is introduced into a compressed air inlet 2 (not shown) using a compressor or the like, and the hot melt adhesive stored in the cylinder 5 is injected into a mold 10.

[0016] As shown in FIG. 2, the mold 10 has an upper mold 11, a lower mold 12, four fastening bolts 13, and a threaded connection portion 14.

[0017] After aligning the upper mold 11 and the lower mold 12 so that they face each other, a gap 15 is formed between the upper mold 11 and the lower mold 12 by tightening them with four tightening bolts 13.

[0018] When the connecting screw portion 7 is connected to the screw connection portion 14, the hot melt adhesive heated to a predetermined temperature by the silicone heater 4 is injected from the cylinder 5 through the screw connection portion 14 into the cavity 15 of the mold 10.

[0019] After that, the hot melt adhesive injected into the gap 15 is cooled, and then the four tightening bolts 13 are removed to separate the upper mold 11 and the lower mold 12, allowing the adhesive sheet formed into a plate shape to be removed.

[0020] The adhesive sheet is then cut to a predetermined width.

[0021] Figure 3 shows a frame on which an adhesive sheet is placed: Figure 3(a) is a perspective view of the frame on which the adhesive sheet is placed, and Figure 3(b) is a cross-sectional view of the frame on which the adhesive sheet is placed.

[0022] 3(a) and 3(b), adhesive sheets S1 to S4, each made of a hot melt adhesive formed into a plate shape, are placed on top of a frame F molded from aluminum. The adhesive sheets S1 to S4 are molded to a thickness D that matches the thickness of the gap 15. Furthermore, the adhesive sheets S1 to S4 are each cut to a width that is 2 / 3L of the width L of the frame F.

[0023] Then, for example, the frame F is heated to about 270°C by a hot air heater (not shown). As a result, the adhesive sheets S1 to S4 placed on the heated frame F are also heated, thereby increasing the adhesive strength between the adhesive sheets S1 to S4, which are molded from a polyolefin-based hot melt adhesive, and the frame F, which is molded from aluminum.

[0024] Then, as shown in FIG. 4, gauze R is stretched under a certain tension so as to cover the adhesive sheets S1 to S4.

[0025] By applying a hot air heater at approximately 270°C to the adhesive sheets S1 to S4 placed on the frame F, the hot melt adhesive melts and the aluminum part of the frame F is heated to approximately 170°C, causing the polyolefin hot melt adhesive to become transparent. By allowing it to cool naturally in this state, the affinity between the frame F and the adhesive sheets S1 to S4 improves, making it less likely for boundary peeling to occur. At this time, the frame F and adhesive sheets S1 to S4 can withstand a shear tension of 15N.

[0026] If the gauze R is stretched without heating the aluminum-molded frame F, peeling may occur at the boundaries between the frame R and the adhesive sheets S1 to S4. (Addendum) The present application discloses the following inventions.

[0027] (Appendix 1) A sheet of polyolefin-based hot melt adhesive is placed on a plate-making frame for screen printing, and the plate-making frame is heated together with the polyolefin-based hot melt adhesive at a predetermined temperature. A gauze bonding method characterized by the above.

[0028] This causes the polyolefin-based hot melt adhesive formed into a sheet and placed on the heated frame to also be heated, thereby increasing the adhesive strength between the polyolefin-based hot melt adhesive and the frame, thereby preventing the polyolefin-based hot melt adhesive from shifting position or peeling at the boundary even when tension is applied to the gauze. [Explanation of symbols]

[0029] 1. Adhesive sheet generating device 2 Compressed air inlet 3 Relief valve 4 Silicone heater 5 cylinders 6 Adjusting valve 7 Connection screw part 10. Mold 11 Upper mold 12 Lower mold 13 Fastening bolt 14 Threaded connection 15 void F frame R frame S1~S4 adhesive sheets

Claims

[Claim 1] A sheet of polyolefin-based hot melt adhesive is placed on a plate-making frame for screen printing, and the plate-making frame is heated together with the polyolefin-based hot melt adhesive at a predetermined temperature. A gauze bonding method characterized by the above.

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