Forming method

Abstract

To provide a molding method that can easily process a surface of a resin sheet.SOLUTION: Provided is a molding method for a sheet for thermoforming. The sheet for thermoforming has a thermoplastic resin sheet. The sheet for thermoforming is a color-coded sheet that includes a plurality of areas of different colors on a surface of the resin sheet. The molding method has a heating process (step ST1) and a molding process (steps ST3-ST8). The heating process is a process of heating the color-coded sheet by light irradiation. The molding process is a process of pressing the color-coded sheet against a mold so as to be processed into a shape in line with the mold.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates generally to molding processes, and more particularly to molding processes for processing resin sheets. [Background technology]

[0002] Conventionally, there is known a method of heating and molding a resin sheet. In the method of manufacturing a container-shaped molded product described in Patent Document 1, a sheet material (resin sheet) made of a heat-meltable fluororesin is heated and then vacuum-molded or vacuum-pressure molded into a predetermined container or box shape. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2009-214412 A Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present disclosure is to provide a molding method that can easily process the surface of a resin sheet. [Means for solving the problem]

[0005] A molding method according to one aspect of the present disclosure is a molding method for a thermoforming sheet. The thermoforming sheet includes a thermoplastic resin sheet. The thermoforming sheet is a color-coded sheet including a plurality of regions, each having a different color, on the surface of the resin sheet. The molding method includes a heating step and a molding step. The heating step is a step of heating the color-coded sheet by irradiating it with light. The molding step is a step of pressing the color-coded sheet against a mold and processing it into a shape that conforms to the mold. In the molding method, in the heating step, unevenness is generated on the surface of the resin sheet due to differences in light absorptance among the multiple regions. Effect of the Invention

[0006] The present disclosure has an advantage that the surface of the resin sheet can be easily processed. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a flow chart showing a molding method according to one embodiment. [Diagram 2] FIG. 2 is a perspective view of a resin sheet used as a material in the molding method. [Diagram 3] FIG. 3 is a perspective view of a color-coded sheet produced from the resin sheet in the molding method. [Figure 4] FIG. 4 is a cross-sectional view of a color-coded sheet and two molds in the molding method. [Diagram 5] FIG. 5 is a cross-sectional view of a color-coded sheet and two molds in the molding method. [Figure 6] FIG. 6 is a front image of the urinal body manufactured by the above molding method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] The molding method according to the embodiment will be described below with reference to the drawings. However, the embodiment described below is merely one of various embodiments of the present disclosure. The embodiment described below can be modified in various ways depending on the design, etc., as long as the object of the present disclosure can be achieved. In addition, each figure described in the embodiment described below is a schematic diagram, and the size and thickness ratio of each component in the figure do not necessarily reflect the actual dimensional ratio.

[0009] (1) Overview The molding method of this embodiment is a method of molding a resin sheet 2 (see FIG. 2) into a desired shape by sheet blow molding. In addition, in the molding method of this embodiment, the resin sheet 2 is molded into a desired shape, and unevenness is also formed on the surface 21 (see FIG. 2) of the resin sheet 2. Then, a pattern, letters, etc. become visible to people due to shadows generated by the unevenness.

[0010] More specifically, as shown in Figs. 1 to 3, the molding method of this embodiment is a molding method for a thermoforming sheet. The thermoforming sheet includes a thermoplastic resin sheet 2. The thermoforming sheet is a color-coded sheet 1 including a plurality of regions, each of which has a different color, on a surface 21 of the resin sheet 2. The molding method includes a heating step (step ST1) and a molding step (steps ST3 to ST8). The heating step is a step of heating the color-coded sheet 1 by irradiating it with light. The molding step is a step of pressing the color-coded sheet 1 against a mold 5 (see Figs. 4 and 5) and processing it into a shape that conforms to the mold 5.

[0011] When the color-coded sheet 1 is irradiated with light, the molding temperature differs in each region due to the difference in light absorptivity in the multiple regions. As a result, the thickness of the resin sheet 2 differs in each region, and unevenness occurs on the surface 21.

[0012] By the molding method of this embodiment, the surface 21 of the resin sheet 2 can be easily processed, and thus, a pattern or letters or the like can be formed by projections and recesses on the surface 21. In this way, the molding method allows a design to be easily formed on the surface 21.

[0013] Moreover, by changing the color applied to the surface 21, the molding temperature can be adjusted, and the thickness of each region of the resin sheet 2 can be freely controlled.

[0014] (2)Details The molding method of this embodiment will be described in more detail below.

[0015] In this embodiment, a lattice pattern is applied by coloring to the surface 21 of the resin sheet 2 before it is heated (see FIG. 3). Then, when the resin sheet 2 is heated and stretched, the pattern is changed to a distorted lattice-like pattern consisting of projections and recesses (see FIG. 6). As a result, the pattern is not only visible to people due to the color, but also due to the shadows cast by the projections and recesses. Even if the color applied by coloring is removed, people can still see the pattern.

[0016] Also, in this embodiment, a case where the main body 8 of a male urinal (see FIG. 6) is manufactured by molding the resin sheet 2 will be described as an example.

[0017] In addition to the heating step and the molding step described above, the molding method may further include a coloring step. The coloring step is a step for forming the color separation sheet 1 from the resin sheet 2. The coloring step is a step of coloring at least a part of the surface 21 so that the colors are different for each of a plurality of regions on the surface 21 of the resin sheet 2.

[0018] FIG. 2 shows the resin sheet 2 at a point in time before the coloring step. The material of the resin sheet 2 is, for example, ASA (acrylate styrene acrylonitrile) resin. The surface 21 of the resin sheet 2 is planar. The color of the surface 21 is, for example, a white-based color. By coloring a part of this surface 21 with a black-based color, as shown in FIG. 3, the surface 21 is color-separated into a white-based color and a black-based color. That is, the surface 21 is color-separated into the color of the resin sheet 2 itself and a color darker than the color of the resin sheet 2 itself. Hereinafter, among the surface 21, the region R1 (or the region that is colored later by the coloring step) colored in the coloring step will be referred to as the "colored region", and the other region R2 will be referred to as the "non-colored region". The colored region is a lattice-shaped region. The non-colored region is a set of a plurality of rectangular compartments arranged in a matrix.

[0019] The coloring step of this embodiment includes a step of applying a black-based paint in a lattice pattern on the surface 21 of the resin sheet 2 by a printing method. That is, the member including at least the resin sheet 2 and the paint applied to the surface 21 of the resin sheet 2 is the color separation sheet 1. In this way, it is preferable that the coloring step includes a step of coloring at least a part (colored region) of the surface 21 of the resin sheet 2 by a printing method. By using the printing method, the surface 21 of the resin sheet 2 can be easily colored in various patterns and letter shapes. The printing method is preferably, for example, a screen printing method.

[0020] The multiple regions of the surface 21 of the resin sheet 2, each having a different color, include the above-mentioned colored region and non-colored region. That is, the multiple regions include a white region (non-colored region) that is the color of the resin sheet 2 itself. Furthermore, the multiple regions include a black region (colored region).

[0021] At least one of the multiple regions (colored region) forms a repeating pattern. In other words, a repeating pattern is formed on the surface 21 of the resin sheet 2 by color coding. More specifically, at least one of the multiple regions (colored region) forms a lattice pattern. A repeating pattern is a pattern (figure) in which a predetermined shape appears regularly and repeatedly in a certain direction.

[0022] Next, the heating step will be described. The heating step is a step of heating the surface of the color-coded sheet 1 by irradiating the color-coded sheet 1 with light. The resin sheet 2 becomes soft by heating, and becomes easier to shape in the molding step. The heating step is carried out, for example, before the molding step. Also, the heating step may be carried out, for example, during the molding step.

[0023] The heating step includes a step of irradiating light (infrared rays) from an infrared heater to the color-coded sheet 1. Examples of infrared heaters include halogen heaters and carbon heaters. The light irradiated from the infrared heater to the color-coded sheet 1 in the heating step is preferably far-infrared rays. In this case, the light is easily absorbed by the resin constituting the resin sheet 2.

[0024] When light is irradiated onto the color-coded sheet 1, the temperature varies from region to region due to the difference in light absorptance between the regions. Specifically, the black-colored regions have a higher light absorptance than the white-colored regions, and therefore the temperature is higher.

[0025] Due to the temperature difference between the regions, unevenness occurs on the surface 21 of the resin sheet 2. That is, in the area where the light absorptance is relatively high, the temperature rise is large, so that the area of ​​the resin sheet 2 is significantly deformed and recessed. On the other hand, in the area where the light absorptance is relatively low, the temperature rise is small, so that the amount of deformation of the area of ​​the resin sheet 2 is small. As a result, the area where the light absorptance is relatively high is recessed more than the area where the light absorptance is relatively low. Specifically, the black-colored area is recessed more than the white-colored non-colored area.

[0026] Next, the molding process will be described. In the molding process, the color-coded sheet 1 is processed so that the colored surface 21 of the resin sheet 2 becomes the front surface of the urinal body 8 (see FIG. 6). The molding process includes a blowing process and a vacuuming process.

[0027] In the molding process of this embodiment, the color-coded sheet 1 is molded by a plug assist method. As shown in Figs. 4 and 5, a plurality (two) dies 5 are used in the molding process. The plurality of dies 5 include a lower die 6 and a plug 7. The lower die 6 has a recess 61 into which at least a portion of the color-coded sheet 1 is inserted. The plug 7 can be inserted into the recess 61 so as to sandwich the color-coded sheet 1 between the plug 7 and the bottom surface of the recess 61. The plug 7 is positioned above the lower die 6.

[0028] Prior to the molding step, a heating step is performed (step ST1). In the heating step, the color-coded sheet 1 held by the clamp is heated and softened. After that, the color-coded sheet 1 is placed between the lower mold 6 and the plug 7 while still being held by the clamp (step ST2) (see FIG. 4).

[0029] Next, the blowing process is started (step ST3). In the blowing process, air is blown onto the color-coded sheet 1. That is, air is blown onto the color-coded sheet 1, and the color-coded sheet 1 is stretched. The air is blown up from below. The color-coded sheet 1 is deformed so as to cover the plug 7.

[0030] Furthermore, the plug 7 is inserted into the recess 61 of the lower die 6 while pressing the color-coded sheet 1 (step ST4) (see FIG. 5). The plug 7 presses the color-coded sheet 1 against the lower die 6, and adjusts the shape of the color-coded sheet 1. The blowing process is also performed at this time, so that the color-coded sheet 1 is pressed against the plug 7 by air, and is molded into a shape that matches the plug 7.

[0031] Next, the lower mold 6 is raised (step ST5). In parallel with raising the lower mold 6, a vacuuming process is performed (step ST6). In the vacuuming process, air is sucked out between the color-coded sheet 1 and the lower mold 6 through a plurality of holes provided in the lower mold 6, and the color-coded sheet 1 is brought into close contact with the lower mold 6.

[0032] Next, the color-coded sheet 1 is cooled and hardened (step ST7). Furthermore, the color-coded sheet 1 is released from the lower mold 6 (step ST8). After that, the processing of the color-coded sheet 1 is completed through processes such as deburring. In other words, a molded product (urinal body 8) is manufactured using the color-coded sheet 1 as a material (see FIG. 6).

[0033] Thus, in the molding method of this embodiment, the molding step includes a step of pressing the color-coded sheet 1 against the mold 5 by air blowing. The molding step also includes a step of sucking the color-coded sheet 1 into the mold 5 by vacuum drawing.

[0034] (Modification of the embodiment) Modifications of the embodiment will be listed below. The following modifications may be implemented in appropriate combination.

[0035] The article manufactured by the molding method of the present disclosure is not limited to the urinal body 8. For example, a container, a pipe, a basket, or the like may be manufactured by the molding method of the present disclosure.

[0036] In the coloring step, instead of the screen printing as the printing method, at least a part (colored region) of the surface 21 of the resin sheet 2 may be colored by inkjet printing. Also, in the coloring step, instead of the printing method, for example, the surface 21 may be colored by fixing a colored member (tape, cloth, etc.) to the surface 21 of the resin sheet 2, or by using a pen. In particular, it is preferable that the surface 21 is colored by fixing a sealant that can be peeled off after molding of the resin sheet 2 to the surface 21, and in this case, by removing the sealant, a molded product without added color can be manufactured. Also, the surface 21 may be colored by ink or the like that can be removed by washing or the like.

[0037] The lattice pattern on the surface 21 of the resin sheet 2 may be a pattern in which the positions of the colored regions (black regions) and the positions of the non-colored regions (white regions) are interchanged with respect to the embodiment.

[0038] On the surface 21 of the resin sheet 2, an irregular pattern may be formed by color coding instead of a repeating pattern.

[0039] The repeating pattern is not limited to a lattice pattern. The repeating pattern may be, for example, a honeycomb pattern. Alternatively, the repeating pattern may be, for example, a pattern in which triangles or parallelograms are closely packed together (plane tessellation). Alternatively, the repeating pattern may be a pattern created by repeatedly arranging a certain pattern.

[0040] The color coding of the surface 21 of the resin sheet 2 is not limited to white-based and black-based colors. For example, the surface 21 may be color coded using colors of red, blue, green, or the like. The surface 21 may also be color coded using more than two colors.

[0041] In the coloring step, a pattern or the like may be applied only to a part of the surface 21 of the resin sheet 2.

[0042] The flowchart shown in FIG. 1 is merely an example of a molding method according to the present disclosure, and the order of steps may be changed as appropriate, and steps may be added or omitted as appropriate.

[0043] (summary) The above-described embodiments and the like disclose the following aspects.

[0044] The molding method according to the first aspect is a molding method for a thermoforming sheet. The thermoforming sheet includes a thermoplastic resin sheet (2). The thermoforming sheet is a color-coded sheet (1) including a plurality of regions of different colors on a surface (21) of the resin sheet (2). The molding method includes a heating step (step ST1) and a molding step (steps ST3 to ST8). The heating step is a step of heating the color-coded sheet (1) by irradiating it with light. The molding step is a step of pressing the color-coded sheet (1) against a mold (5) and processing it into a shape that fits the mold (5).

[0045] According to the above configuration, the degree of temperature rise in the heating process differs among the multiple regions depending on the difference in color (light absorptivity) of the surface (21) of the resin sheet (2). As a result, after the heating process is completed, the properties of the surface (21) of the resin sheet (2) change. For example, one of the multiple regions on the surface (21) of the resin sheet (2) becomes more recessed than another region. In this way, according to the above molding method, the surface (21) of the resin sheet (2) can be easily processed.

[0046] In addition, the molding method according to the second aspect is the same as the first aspect, but further includes a coloring step for forming the color-coded sheet (1) from the resin sheet (2). The coloring step is a step of coloring at least a part of the surface (21) of the resin sheet (2) so that the color varies from region to region in the surface (21).

[0047] According to the above arrangement, a color-coded sheet (1) can be provided.

[0048] In the molding method according to the third embodiment, the coloring step in the second embodiment includes a step of coloring at least a part of the surface (21) by a printing method.

[0049] According to the above-mentioned configuration, the surface (21) of the resin sheet (2) can be easily colored in various patterns or letter shapes by using a printing method.

[0050] In the molding method according to a fourth aspect, in any one of the first to third aspects, the heating step includes a step of irradiating the color-coded sheet (1) with infrared rays from an infrared heater.

[0051] According to the above configuration, the color-coded sheet (1) can be locally heated.

[0052] In the molding method according to the fifth aspect, in any one of the first to fourth aspects, the plurality of regions includes a white region which is the color of the resin sheet (2) itself.

[0053] According to the above configuration, there is no need to color the areas that are to be left as white areas, so the amount of ink or the like used for coloring can be reduced.

[0054] In addition, in the molding method according to a sixth aspect, in any one of the first to fifth aspects, the plurality of regions includes a black-colored region.

[0055] According to the above configuration, the temperature of the blackish region can be increased easily in the heating step, so that the blackish region can be efficiently heated in the heating step.

[0056] In addition, in the molding method according to a seventh aspect, in any one of the first to sixth aspects, at least one region of the plurality of regions forms a repeating pattern.

[0057] According to the above configuration, it is possible to reduce the effort required for coloring at least the partial area.

[0058] In addition, in the molding method according to the eighth aspect, in the seventh aspect, at least one of the plurality of areas forms a lattice pattern.

[0059] According to the above-mentioned configuration, a tile-like resin molded product can be easily formed.

[0060] In addition, in the molding method according to a ninth aspect, in any one of the first to eighth aspects, the molding step includes a step of pressing the color-coded sheet (1) against a mold (5) by air blowing.

[0061] According to the above-mentioned configuration, the color-coded sheet (1) can be closely attached to the mold (5). This reduces distortion of the resin sheet (2). Also, distortion of the pattern on the surface (21) of the resin sheet (2) can be reduced.

[0062] In addition, in the molding method according to a tenth aspect, in any one of the first to ninth aspects, the molding step includes a step of sucking the color-coded sheet (1) into a mold (5) by vacuum drawing.

[0063] According to the above-mentioned configuration, the color-coded sheet (1) can be closely attached to the mold (5). This reduces distortion of the resin sheet (2). Also, distortion of the pattern on the surface (21) of the resin sheet (2) can be reduced.

[0064] The configurations other than that of the first embodiment are not essential to the molding method and can be omitted as appropriate. [Explanation of symbols]

[0065] 1 Color-coded sheet (thermoforming sheet) 2 Resin sheet 5. Mold 21 Surface ST1 step (heating process) ST3~ST8 steps (molding process)

Claims

1. A molding method for a thermoforming sheet, comprising the steps of: The thermoforming sheet includes a thermoplastic resin sheet, and the surface of the resin sheet is a color-coded sheet including a plurality of regions each having a different color, The molding method includes: a heating step of heating the color-coded sheet by light irradiation; A molding process of pressing the color-coded sheet against a mold and processing it into a shape that conforms to the mold, In the heating step, unevenness is generated on the surface of the resin sheet due to differences in light absorptance of the plurality of regions. Molding method.

2. As a process for forming the color-coded sheet from the resin sheet, The method further includes a coloring step of coloring at least a portion of the surface of the resin sheet such that the plurality of regions on the surface have different colors. The molding method according to claim 1.

3. The coloring step includes a step of coloring at least the portion of the surface by a printing method. The molding method according to claim 2.

4. The heating step includes a step of irradiating the color-coded sheet with infrared rays from an infrared heater. The molding method according to any one of claims 1 to 3.

5. The plurality of regions includes a white region which is the color of the resin sheet itself, The molding method according to any one of claims 1 to 4.

6. The plurality of regions includes a black region. The molding method according to any one of claims 1 to 5.

7. At least one of the plurality of regions forms a repeating pattern. The molding method according to any one of claims 1 to 6.

8. At least one of the plurality of regions forms a lattice pattern. The molding method according to claim 7.

9. The molding step includes a step of pressing the color-coded sheet against the mold by air blowing. The molding method according to any one of claims 1 to 8.

10. The molding step includes a step of sucking the color-coded sheet into the mold by vacuum suction. The molding method according to any one of claims 1 to 9.

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