TWI598218B - Polishing method and its finished product and polishing device - Google Patents

Description

Polishing method and finished product and polishing device thereof

The present invention relates to a polishing method and a finished product and polishing apparatus thereof, and more particularly to a method for reducing the surface roughness of a workpiece manufactured by a technique of rapid prototyping using a chemical gas, and a finished product and a polishing apparatus therefor.

Using the techniques of Additive Manufacturing, 3D Printing, or Rapid Prototyping, the actual object of the design can be quickly created after the digital design of a three-dimensional object is completed. The actual object can be used as a three-dimensional model for research or testing during the development process, and can even be used as a tool directly in some industries. The technology of laminated manufacturing includes Fused Deposition Modeling (FDM), which works by heating a hot melt material (such as ABS resin) to its melting point, so that the material is between solid and liquid. . And via computer control (eg, a robotic arm moving along the X-Y axis) the heating head moves along the slice information of the three-dimensional prototype to be manufactured (eg, the two-dimensional geometric information of the CAD). When moving, the nozzle squeezes the hot melt material between the solid and liquid to form a thin layer on the susceptor. When the thin layer is completed, the susceptor is lowered along the Z axis, the thin layer is cured, and a new thin film is formed on the cured thin layer by the processing head. The layers, stacked one after the other, form a three-dimensional prototype from bottom to top.

However, the surface of the three-dimensional prototype printed with FDM has a rough texture that is stepped. The early method of eliminating the texture is to manually grind the surface of the three-dimensionally printed prototype. The disadvantage is that the manual grinding requires a long time of concentration and it is difficult to maintain a certain quality. Moreover, the manual polishing is easy to damage the microscopic features of the three-dimensional prototype. Structure and operation have a dead angle. Techniques such as polishing of minute structures, abrasive flow machining (AFM) methods, and adaptive slicing algorithms have been proposed, but their equipment is expensive and complicated. The chemical solution immersion treatment method is simple and economical, and the method is to soak the object to be immersed in the chemical solution, so that the surface of the three-dimensional prototype is melted to reduce the roughness. However, the chemical solution immersion treatment method still has its disadvantages: the immersion time is difficult to grasp, and it is easy to damage the detailed structure of the three-dimensional prototype itself due to excessive polishing, and it is even possible to reduce the original design volume of the three-dimensional prototype. Further, the chemical solution such as acetone has high volatility and is not easily controlled, and it is easy to pollute the environment during handling and the operator is also likely to inhale a pungent odor.

Accordingly, it is an object of the present invention to provide a polishing apparatus which is advantageous in that it is inexpensive, high in efficiency, high in precision, low in pollution, and environmentally friendly.

Thus, the polishing apparatus of the present invention is adapted to vaporize a chemical solution into a chemical vapor and to use the chemical vapor for polishing a workpiece, the polishing apparatus comprising: a hollow casing for the workpiece to be disposed therein; and a liquid holding unit Connected to the hollow casing and used to hold the chemical liquid; a unit, in communication with the hollow housing, for extracting gas from the hollow housing; a flow guiding unit located in the hollow housing for driving the flow of the chemical vapor; a temperature control unit, connecting The hollow casing is configured to control one of a temperature of the chemical liquid and a temperature of the chemical vapor; and a timing unit is coupled to the hollow casing.

In some embodiments, the polishing apparatus further includes an automatic control module electrically connected to the temperature control unit, the timing unit, and the air extraction unit.

In some embodiments, the liquid receiving unit is a tray located in the hollow casing and having an opening upward. The flow guiding unit is a flow guiding fan, and the guiding unit is disposed above the liquid receiving unit and makes the gas Blow to the liquid unit.

In some embodiments, the polishing apparatus further includes a carrier unit located in the hollow housing, the carrier unit including a plurality of rails, a plurality of protrusions extending upwardly for mounting the workpiece, and a rotary motor, and the like The studs are coupled to the rails and are slidable along the length of the rails and are releasably positionable during the sliding process. Additionally, the rotary motor is controlled to rotate the studs.

In some embodiments, the hollow housing further includes a transparent cover, the polishing device further includes a transparent heating sheet coupled to the cover, and the suction unit includes a gas storage chamber.

Still another object of the present invention is to provide a polishing method which has the advantages of high efficiency, high precision, low pollution, and environmental protection.

Thus, the polishing method of the present invention is suitable for polishing a workpiece, The method comprises the steps of: step (A) setting the workpiece in a chamber; step (B) heating a chemical solution that dissolves the workpiece to produce a chemical vapor; and step (C) providing the chemical vapor to the chamber In the room.

In some embodiments, in the step (B), the heating procedure is performed according to a target temperature with respect to the boiling point of the chemical solution; the execution time of the step (C) is a target based on the surface area of the workpiece Set by time.

In some embodiments, the workpiece is continuously rotated in the step (C), wherein the material of the workpiece is a thermoplastic resin, the chemical solution is acetone, and the chemical vapor is acetone vapor.

In some embodiments, after the step (C), the method further comprises: step (D) cooling the chemical solution, and then performing step (E) to withdraw the chemical vapor in the chamber.

It is still another object of the present invention to provide a finished product produced using the polishing method.

Thus, the finished product of the present invention is obtained by polishing a workpiece using the above-described polishing method, the finished product comprising: a plurality of thin layers laminated on each other and forming a non-flat outer surface, wherein the material of the thin layers is a thermoplastic resin. The chemical solution is acetone; and a molten layer is coated on the outer surface of the thin layers, and the main component of the molten layer is the same as the thin layers.

The effect of the invention is that the workpiece is polished by chemical vapor instead of the chemical liquid, which can improve the precision of polishing. By replacing the artificial monitoring with the automatic control module of the polishing device, the polishing process can be effectively controlled, and the processing efficiency is improved. After the polishing process is completed, the exhaust system is exhausted. The chemical vapor is discharged and the chemical vapor is condensed and recycled to achieve the function of recycling the chemical solution to improve the environmental performance of the polishing device.

1‧‧‧ hollow housing

11‧‧‧ Support

12‧‧‧ Cover

121‧‧‧heated patch

2‧‧‧ Liquid unit

3‧‧‧ Carrying unit

31‧‧‧Rotary motor

32‧‧‧Base

321‧‧‧ Track

322‧‧‧Perforation

33‧‧‧Bump

4‧‧‧temperature control unit

41‧‧‧heater

42‧‧‧heatsink

421‧‧‧ Heatsink

422‧‧‧ cooling fan

43‧‧‧Temperature Sensor

5‧‧‧Guide unit

51‧‧‧ wind direction

6‧‧‧Pumping unit

61‧‧‧ gas storage room

7‧‧‧Control time unit

8‧‧‧Operator panel

81‧‧‧ start button

82‧‧‧ stop button

83‧‧‧Temperature setting button group

84‧‧‧Time setting key group

85‧‧‧Temperature display unit

86‧‧‧Time display unit

9‧‧‧Automatic Control Module

100‧‧‧Workpiece

101, 101’‧‧‧ thin layer

200‧‧‧chemical solution

201‧‧‧Chemical Vapor

300‧‧‧ finished products

301‧‧‧Solid layer

400‧‧ ‧ room

S1‧‧‧ steps

S2‧‧‧ steps

S3‧‧‧ steps

S4‧‧‧ steps

S5‧‧ steps

S6‧‧ steps

S7‧‧ steps

Other features and effects of the present invention will be apparent from the following description of the drawings. FIG. 1 is a flow chart illustrating a polishing method of the present invention. FIG. 2 is a schematic view showing the use of the polishing method. A state in which a workpiece is surrounded by a chemical vapor; FIG. 3 is a schematic view showing a finished product using the polishing method; and FIG. 4 is a side view showing a state in which a workpiece of the polishing apparatus of the present invention is loaded with a workpiece. Figure 5 is a top plan view showing a pedestal and a plurality of studs of the polishing apparatus; and Figure 6 is a front elevational view showing an operation panel of the polishing apparatus.

Before the present invention is described in detail, it should be noted that in the following description, similar elements are denoted by the same reference numerals.

An embodiment of the polishing method of the present invention will be described with reference to Figs. 1, 2 and 3. The polishing method is suitable for polishing a workpiece 100 as shown in FIG. 2, and the workpiece 100 may be made of a material such as thermoplastic resin, by rapid prototyping technology such as melt extrusion deposition molding or 3D printing technology, and A plurality of thin layers 101 are included, and these thin layers 101 are stacked one on another to form a non-flat outer surface. The polishing method of the present invention can polish the workpiece 100 having a non-flat, rough surface in FIG. 2 to form a flat outer surface as shown in FIG. The article 300 specifically includes the following steps: Step S1 is to set the workpiece 100 in a chamber 400. Step S2 is to heat a chemical solution that dissolves the workpiece 100 to generate a chemical vapor 201. The chemical solution and the chemical vapor 201 may be acetone, but not limited thereto. Step S3 provides the chemical vapor 201 in the chamber 400, and the chemical vapor 201 dissolves the material of the outer surface of the workpiece 100 to produce a polishing effect. Step S4 enhances the flow of the chemical vapor 201 in the chamber and drives the concentration of the chemical vapor 201 in the chamber 400 to be nearly uniform, so that the polishing process can be performed stably. In step S5, the workpiece 100 is continuously rotated. When the concentration distribution of the chemical vapor 201 in the chamber 400 is not sufficiently uniform, the problem that the surface polishing degree of the workpiece 100 is inconsistent can be avoided. Step S6 is to cool the chemical solution to reduce the yield of the chemical vapor 201, and step S7 is to withdraw the chemical vapor 201 in the chamber 400 to complete the entire polishing process.

The process of S1 to S3 enables the chemical vapor 201 generated by the chemical solution to polish the workpiece 100, and during the polishing process, steps S2 to S5 can be performed simultaneously. In the above step S2, the heating procedure is performed according to a target temperature with respect to the boiling point of the chemical solution. For example, the chemical solution component in the present embodiment is acetone, and its boiling point is 56 ° C. In this embodiment, the target temperature is set. To be about 1 ° C above the boiling point, that is, to set the target temperature to 57 ° C, the yield of the chemical vapor 201 can be effectively controlled. However, according to actual needs, the setting of the target temperature can be adjusted correspondingly, and is not limited to the content disclosed herein. In this step S3, the execution time is set by a target time with respect to the surface area of the workpiece 100, which is positively correlated with the surface area of the workpiece 100, in other words, has a large surface area. The workpiece 100 needs to set a longer target time.

It should be noted that in other embodiments, the order of step S4 and step S5 may be reversed, and if at least one of the two steps is omitted, the effect of polishing the workpiece can be achieved. In other embodiments, the order of step S6 and step S7 may be reversed, and if at least one of the two steps is omitted, the effect of polishing the workpiece can be achieved.

Referring to FIG. 2 and FIG. 3, the finished product 300 processed by the above polishing method also includes a plurality of thin layers 101' as the workpiece 100, but the outer surface of the thin layers 101' is melted and polished by the chemical vapor 201 to form a molten layer 301. The molten layer 301 has the effect of filling the surface while leaving the finished product 300 with a flat surface. In the present embodiment, since the chemical solution and the chemical vapor 201 are made of acetone which can dissolve the thin layers 101, 101' and have high volatility, the main component of the molten layer 301 of the finished product 300 and the thin layer 101 101' is the same.

Referring to FIG. 4, an embodiment of the polishing apparatus of the present invention is suitable for performing the above polishing method. The polishing apparatus comprises a hollow casing 1, a liquid holding unit 2, a carrying unit 3, a temperature control unit 4, and a guide. The flow unit 5, an air extraction unit 6, a control unit 7, a control panel 8, and an automatic control module 9. It should be noted that the polishing method of the present invention can also be performed by other devices, and is not limited to being performed by the polishing apparatus of the present invention.

The hollow housing 1 includes a support base 11 and a transparent cover 12 covering the top surface of the support base 11. The cover 12 has a plurality of transparent heating patches 121, and the cover 12 and the support base 11 together form a closed chamber 400, which is provided for the workpiece 100 to be accommodated therein. The chemical vapor 201 is subjected to a polishing treatment. By heating the patch 121, the temperature of the cover 12 can be raised to prevent the chemical vapor 201 from condensing on the cover 12, so that the user can observe the workpiece 100.

The liquid receiving unit 2 is in communication with the hollow casing 1 and is used for containing the chemical liquid 200. In the embodiment, the liquid receiving unit 2 is a tray located in the chamber 400. Specifically, the liquid receiving unit 2 is disposed on the top surface of the support base 11 with the opening facing upward. It will be understood by those of ordinary skill in the art that for the structural and functional requirements of the design of the liquid containing unit 2, various types of containers that are in communication with the hollow housing 1 and that contain the chemical solution 200 can be used. And the method of guiding the chemical vapor 201 produced by the chemical solution 200 into the chamber 400 can be achieved using any method. For example, in the present embodiment, the liquid holding unit 2 is placed in the chamber 400, so that the chemical vapor 201 discharged from the liquid holding unit 2 can be directly circulated in the chamber 400. However, the liquid holding unit 2 can also be placed outside the chamber 400 and communicated to the chamber 400 by a gas line not shown in the drawing, so that the chemical vapor 201 can flow from the liquid holding unit 2 into the chamber 400.

Referring to FIG. 4 and FIG. 5, in the embodiment, the carrying unit 3 is disposed in the chamber 400, and includes a rotating motor 31, a base 32 having a plurality of rails 321 and a plurality of through holes 322, and a plurality of upwardly extending for A stud 33 of the workpiece 100 is mounted. The perforations 322 serve as passages for the chemical vapor 201 to pass through the susceptor 32. The studs 33 are coupled to the rails 321 and are slidable along the length of the rails 321 (as indicated by the phantom arrow in Figure 5) and are releasably positionable during sliding. Specifically, the protrusions 33 are equal in length and respectively hold the workpiece 100 at the top end thereof to make the workpiece 100 All surfaces (including the bottom surface) can be exposed to the chemical vapor 201 to ensure that each face of the workpiece 100 can be polished by the chemical vapor 201. The rotary motor 31 is controlled to rotate the base 32. By rotating the workpiece 100 by the rotation motor 31 to ensure that the flow of the chemical vapor 201 in each unit of the workpiece 100 is approximated in the event of uneven flow of the chemical vapor 201, the polishing treatment can be improved. Uniformity. It should be noted that in other embodiments, even if the carrying unit 3 does not have the rotating motor 31, it can be implemented.

Specifically, the number of the tracks 321 is two and intersects each other. The number of the protrusions 33 is four, and the positions of the protrusions 33 on the tracks 321 are determined according to the size of the workpiece 100. fixed. In the present embodiment, the number of the tracks 321 and the number of the protrusions 33 are only for clearly showing the inventive concept of the embodiment, and are not limited to any number of the tracks 321 in different embodiments. The studs 33. In other implementations, the pedestal 31 may be omitted to implement the tracks 321 . It should be understood by those of ordinary skill in the art that the structural and functional requirements for the design of the tracks 321 may be A track design different from the present embodiment is used, and any method can be used to achieve the purpose that the studs 33 slide along the length of the rails 321 and can be releasably positioned during sliding. It should be noted that, in other embodiments, the carrying unit 3 may not be implemented. For example, the workpiece 100 may be polished on the top surface of the support base 11 .

The temperature control unit 4 is connected to the hollow casing 1 for controlling one of the temperature of the chemical liquid 200 and the temperature of the chemical vapor 201. in In this embodiment, the temperature control unit 4 is mainly used to control the temperature of the chemical liquid 200. The temperature control unit 4 is connected to the liquid receiving unit 2 and includes a heater 41, a heat sink 42 and a temperature sensor 43. The heater 41 is a heating sheet, and the heater 41 is connected to the liquid receiving unit 2 for heating the liquid holding unit 2 and further raising the temperature of the chemical solution 200 in the liquid holding unit 2. The heat sink 42 has a heat sink 421 and a heat dissipation fan 422. The heat sink 42 is connected to the support base 11 and is in contact with the bottom surface of the liquid receiving unit 2 for lowering the temperature of the liquid holding unit 2 and further reducing the temperature. The temperature of the chemical solution 200. The temperature sensor 43 is connected to the liquid receiving unit 2 and used to measure the temperature of the liquid receiving unit 2.

The flow guiding unit 5 is located in the hollow casing 1 and is used to drive the flow of the chemical vapor 201. In the present embodiment, the flow guiding unit 5 is a flow guiding fan, and the flow guiding unit 5 is disposed above the liquid holding unit 2 to generate an air flow, and the direction 51 of the air flow faces the opening of the liquid receiving unit 2. In addition, by providing the flow guiding unit 5 above the liquid holding unit 2, the flow guiding unit 5 can have the flow of the chemical vapor 201 in the reinforcing container 400 and accelerate the accumulation of the chemical solution 200 at the top of the chemical solution 200. The effect of the chemical vapor 201 on the surface, and the convection of the gas at the top and bottom of the chamber 400, so that the chemical vapor 201 escaping from the liquid holding unit 2 flows upward to the workpiece 100 for polishing, and can also be improved. The gas distribution uniformity in the chamber 400. In different implementations, the flow guiding unit 5 is not limited to be disposed at the bottom of the chamber 400, and the number is not limited to a single one, and may be adjusted correspondingly according to actual needs.

The air extraction unit 6 is connected to the chamber 400 of the hollow housing 1 It is used to evacuate the gas inside the hollow casing 1. In the present embodiment, the air extraction unit 6 has a gas storage chamber 61 for storing the chemical vapor 201 extracted from the chamber 400, and can recover the chemical vapor 201, and the chemical vapor 201 is cooled. It condenses into a chemical liquid 200, which can be recycled, and is environmentally friendly and has no exhaust gas pollution.

The timing unit 7 is connected to the hollow casing 1 for measuring the length of time during which the workpiece 100 is polished. In this embodiment, the timing unit 7 is a timer that is electrically connected to the control panel 8 and the automatic control module 9.

Referring to FIG. 6 , the control panel 8 is connected to the hollow casing 1 and has a start button 81 , a stop button 82 , a temperature setting member set 83 , a time setting member group 84 , a temperature display unit 85 , and The unit 86 is displayed for a time.

The automatic control module 9 is electrically connected to the temperature control unit 4, the timing unit 7, and the air extraction unit 6. In the embodiment, the automatic control module 9 is also electrically connected to the control panel 8, the flow guiding unit 5, the rotating motor 31 and the timing unit 7. The automatic control module 9 includes a microcontroller (not shown) and a plurality of relays (not shown) electrically connected to the microcontroller, and the automatic control module 9 controls the relays via the microcontroller to It is determined whether power is supplied and the components that are electrically connected to the automatic control module 9 are activated.

The user can press the start button 81 after the control panel 8 inputs a target time and a target temperature, and the automatic control module 8 activates the heater 41 in the temperature control system 4 to raise the temperature of the liquid receiving unit 2. . After rising to the target temperature, the automatic control module 8 turns off the heater 41 and activates the flow guiding unit 5, the rotary motor 31, and the timing system 7. When After the target time is over, the automatic control module 8 closes the flow guiding unit 5, the rotating motor 31 and the timing system 7 and activates the air extracting unit 6 and the heat sink 42 in the temperature control system 4.

Referring to FIG. 1 to FIG. 5, according to the above embodiment of the polishing apparatus, if the polishing apparatus is applied to the polishing method of the present invention, the specific execution step is: in step S1, the user can according to the volume and shape of the workpiece 100. The placement position and the separation distance of the studs 33 are set in advance, and the workpiece 100 is placed on the carrying unit 3 in the chamber 400 of the hollow casing 12. After the target time and the target temperature required for the polishing process are set in the operation panel 8 in steps S2 and S3, the chemical solution 200 in the liquid receiving unit 2 is heated by the heater 41 of the temperature control unit 4 to accelerate the evaporation of the chemical solution 200. The speed of the chemical vapor 201 is such that an environment rich in the chemical vapor 201 is formed in the chamber 400, and the polishing process of the workpiece 100 can be performed. The heating process is performed by the temperature control unit 400 to heat the temperature to the target temperature and maintain the target temperature to facilitate controlling the polishing process to be performed in a stable state. In steps S4 and S5, when the polishing process is performed, the flow guiding unit 5 continues to operate to improve the fluidity and distribution uniformity of the chemical vapor 201. The rotary motor 31 of the carrying unit 3 can also be turned on when necessary to drive the workpiece 100 to rotate within the chamber 400. Steps S6, S7, when the polishing process is finished, the heat sink 42 of the temperature control unit 4 cools the temperature of the liquid receiving unit 2 to reduce the amount of chemical vapor 201 generated, and the pumping unit 6 can extract the chemical vapor 201 in the chamber 400. And recycling, the workpiece 100 is polished to the finished product 300.

In summary, the polishing method of the present invention provides a processing method for polishing a workpiece by chemical vapor, which has a high The advantages of precision, low pollution and environmental protection. If the method is carried out by the polishing apparatus of the present invention, the flow guiding unit 5 of the polishing apparatus directly acts on the surface of the chemical liquid 200 while accelerating its evaporation and driving the airflow in the hollow casing 1. The rotation of the workpiece 100 by the rotary motor 31 to ensure that the vapor concentration of each face of the workpiece 100 is contacted per unit time is approximate. The polishing process is controlled by the automatic control module 9, and the quality of the polishing can be maintained without manual monitoring throughout the process. The transparent heating patch 121 is added to the transparent cover 12 to prevent the chemical vapor 201 from condensing on the cover 12 for viewing the workpiece 100. Therefore, the polishing method and polishing apparatus of the present invention can achieve the object of the present invention.

However, the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the scope of the present invention, that is, the simple equivalent changes and modifications made by the scope of the invention and the contents of the patent specification, All remain within the scope of the invention patent.

1‧‧‧ hollow housing

11‧‧‧ Support

12‧‧‧ Cover

121‧‧‧heated patch

2‧‧‧ Liquid unit

3‧‧‧ Carrying unit

31‧‧‧Rotary motor

32‧‧‧Base

33‧‧‧Bump

4‧‧‧temperature control unit

41‧‧‧heater

42‧‧‧heatsink

421‧‧‧ Heatsink

422‧‧‧ cooling fan

43‧‧‧Temperature Sensor

5‧‧‧Guide unit

51‧‧‧ wind direction

6‧‧‧Pumping unit

61‧‧‧ gas storage room

7‧‧‧Control time unit

8‧‧‧Operator panel

9‧‧‧Automatic Control Module

100‧‧‧Workpiece

200‧‧‧chemical solution

400‧‧ ‧ room

Claims (9)

A polishing apparatus adapted to vaporize a chemical solution into a chemical vapor and to use the chemical vapor for polishing a workpiece, the polishing apparatus comprising: a hollow casing for the workpiece to be disposed therein; a liquid holding unit, and the a hollow housing is connected to receive the chemical liquid; an air extraction unit is in communication with the hollow housing for extracting gas from the hollow housing; and a flow guiding unit is located in the hollow shell a control unit for controlling the flow of the chemical vapor; a temperature control unit coupled to the hollow housing for controlling the temperature of the chemical liquid; a timing unit coupled to the hollow housing; and a load bearing unit Locating in the hollow housing, comprising a plurality of rails, a plurality of protrusions extending upwardly for mounting the workpiece, and a rotating motor coupled to the rails and capable of sliding along the length of the rails and capable of The positioning is releasable during the sliding process, and in addition, the rotating motor is controlled to drive the protrusions to rotate. The polishing apparatus of claim 1, further comprising an automatic control module electrically connected to the temperature control unit, the timing unit, and the air extraction unit. The polishing apparatus according to claim 1, wherein the liquid receiving unit is a tray located in the hollow casing and having an opening upward, the flow guiding unit is a flow guiding fan, and the guiding unit is disposed above the liquid receiving unit. The gas is blown to the liquid receiving unit. The polishing apparatus according to claim 1, wherein the hollow casing further comprises a transparent cover, the polishing device further comprising a transparent heating patch connected to the cover, and further, the air extraction unit comprises A gas storage room. A polishing method for polishing a workpiece by the polishing apparatus according to any one of claims 1 to 4, the method comprising the steps of: (A) setting the workpiece in a chamber; and heating in the step (B) Dissolving a chemical solution of the workpiece to produce a chemical vapor; and step (C) providing the chemical vapor in the chamber. The polishing method according to claim 5, wherein in the step (B), the heating program is performed according to a target temperature with respect to a boiling point of the chemical solution; the execution time of the step (C) is related to the workpiece The surface area is set for a target time. The polishing method according to claim 5, wherein the workpiece is continuously rotated in the step (C), wherein the material of the workpiece is a thermoplastic resin, the chemical solution is acetone, and the chemical vapor is acetone vapor. The polishing method according to claim 5, further comprising, after the step (C), the step (D) of cooling the chemical solution, and then performing the step (E) of withdrawing the chemical vapor in the chamber. A finished product obtained by polishing a workpiece using a polishing apparatus as claimed in claims 1 to 4, the finished product comprising: a plurality of thin layers laminated on each other, and the edges of the mutually stacked thin layers together form a non-flat outer surface a surface, wherein the material of the thin layer is a thermoplastic resin, and the chemical solution is acetone; a molten layer coated on the non-flat outer surface of the thin layer, the molten layer being cooled by melting a part of the non-flat outer surface of the thin layer, and the main component and the thin layer the same.