TW201400296A - Method for attaching plastic film to article surface - Google Patents

Abstract

A method for attaching a plastic film to the surface of an article is disclosed, which includes the following steps: step one: forming the plastic film into a three-dimensional shape, where the three-dimensional shape is defined according to the surface contour of an article that is to be decorated with the plastic film; step two: placing the three-dimensional plastic film and the article in an airtight mould that can realize vacuum environment; step three: heating the plastic film inside the airtight mould so as to transform an adhesion layer of the plastic film into an adhesive state from a solid state and to make the plastic film malleable; step four: lowering the air pressure between the plastic film and the article to a negative pressure state so that the plastic film is attached onto the article surface through the adhesion layer; step five: applying a uniform pressure on the outer surface of the plastic film, where the pressure can be a mechanical pressure or an air pressure, so that the plastic film can be completely attached on the surface of the article smoothly, and tightly attached and extended along the curvature, convex, concave and other irregular parts of the article surface.

Description

Method of attaching a plastic film to the surface of an article

The present invention relates to a method of attaching a plastic film to the surface of an article.

Regarding the method of attaching a pattern or pattern to the three-dimensional surface of an article, a screen printing method can be employed. First, the pattern layer is printed on the surface of the article, and the pattern layer is fixed on the surface of the article, and then the article and the pattern layer are presented in a predetermined three-dimensional shape by vacuum or thermoforming.

One of the disadvantages of the above solution is that the printing material of the pattern layer needs to be particularly carefully selected, and the heat-resistant plastic material is preferably used to prevent the subsequent vacuum or hot press forming process from damaging the pattern layer. The second disadvantage is that the use of screen printing will limit the performance of the pattern layer in terms of color, pattern, pattern, gloss, light and shade. The third disadvantage is that the curved portion of the article is cracked or peeled off due to a change in tension during molding. The fourth disadvantage is that the pattern layer is not easy to adhere for a long time, and the pattern layer gradually peels off after a period of use.

Replacing the screen printing technology with a patterned pattern film. In other words, the surface is modified by attaching a pattern film to the surface of the article. Compared to screen printing, the patterned film can exhibit more diverse colors, graphics, patterns, gloss, light and dark performance, and can be maintained for a long time. However, one of the problems to be overcome is how to make the patterned film adhere smoothly along the three-dimensional shape of the surface of the article, in particular, how to overcome the curved surface of the curved surface, the undulating junction, and the corner of the film without wrinkles, fracture. The second problem to be overcome is how to avoid the problem of unevenness due to air bubbles between the pattern film and the surface of the article. The third problem to be overcome is the attachment pattern. In the process of patterning the film, how to protect the surface of the film from scratches or breakage caused by external force (for example, removing the pressing force of the bubble)

A method for attaching a plastic film to a surface of an article, comprising: step 1: forming a plastic film into a three-dimensional shape, wherein the three-dimensional shape is determined according to a shape of a surface to be modified by a plastic film; a plastic film formed into a three-dimensional shape and the article is placed in a gas-tight mold capable of realizing a vacuum environment; in step three, the plastic film is heated in the airtight mold to change the adhesive layer of the plastic film from a solid to a glue And the plastic film is malleable; in step 4, the pressure between the plastic film and the article is reduced to a negative pressure state, and the plastic film is attached to the surface of the article with the adhesive layer; The outer surface of the plastic film uniformly applies a pressure, which may be a soft mechanical pressure or a gas pressure, so that the plastic film can be completely flat attached to the surface of the article, and can follow the curvature of the surface of the article, the convex portion, The recess and other irregularities fit snugly together.

A plastic film can be attached to the surface of any article, which has been prefabricated in various colors, patterns, patterns, gloss, and light and dark to modify the surface of the article.

The plastic film has been formed into a three-dimensional shape in advance according to the surface shape of the article, so that the plastic film can be attached to the surface of the article accurately in the mold, and adheres completely in conformity with the three-dimensional shape of the article. In particular, the film stickers at the curved surface, the undulating junction, and the corners remain flat and tightly extended.

Pressing the surface of the plastic film with gas pressure or soft mechanical pressure to remove the gap between the plastic film and the surface of the article and the air, so that the plastic film can be completely flattened on the surface of the article, and not on the surface of the plastic film. Will form a scratch of pressure.

The invention can reduce working time and increase production.

As shown in the first figure, the apparatus of the present invention generally includes a lower mold 20, an upper mold 40, a vacuum system 10 connecting the upper mold 40 and the lower mold 20, and a heating device 50 connecting the upper mold 40. The upper mold 40 and the lower mold 20 are relatively joined and kept airtight. An article 21 is positioned in the cavity 22 of the lower mold 20, and a plastic film 31 is positioned in the cavity 42 of the upper mold 40, and an intermediate space 30 is formed between the two surfaces of the upper mold 40. The plastic film 31 is preformed in accordance with the three-dimensional shape of the surface of the article 21, and the plastic film 31 has a three-dimensional shape corresponding to the surface of the article 21. The vacuum system 10 controls the evacuation of the lower mold 20 and the upper mold 40 through the two lines 11, 12 and the switches 13, 14 respectively. The upper and lower mold vacuuming operations may be turned on or off separately or simultaneously depending on the situation.

As shown in the second figure, the structure of the plastic film 31 of the present invention mainly includes an adhesive layer 311, a pattern layer 312, a plastic layer (PET layer) 313, and a hardened layer 314. The lower surface of the plastic layer 313 is a pattern layer 312. The pattern of the pattern layer 312 and the concave and convex three-dimensional texture are obtained by printing or transfer. The upper surface of the plastic layer 313 is the hardened layer 314, and the adhesive layer 311 is attached thereto. The lower surface of the pattern layer 312. The technical solution for pre-forming the plastic film 31 in accordance with the three-dimensional shape of the surface of the article 21 includes, but is not limited to, vacuum forming and hot press forming.

As shown in the third figure, when the upper mold 40 and the lower mold 20 are combined, a gas-tight mold is formed. The heating device 50 is activated to heat the plastic film 31 in the upper mold 40. The heating temperature varies depending on the characteristics of the plastic film. In principle, the adhesive layer 311 of the plastic film 31 is changed from a solid to a viscose. And the plastic film 31 is made to have ductility, and the temperature is about 110 ° C to 190 ° C. Thereafter, the vacuum system 10 is activated to evacuate the intermediate space 30 between the plastic film 31 and the article 21 and the cavity 42. The negative pressure acts to adhere the plastic film 31 to the surface of the article 21 with the adhesive layer 311. Since the plastic film 31 has been preformed in accordance with the three-dimensional surface of the article 21, the plastic film 31 can be completely in accordance with the surface shape of the article 21. Precise attachment and bonding.

After the plastic film 31 is attached to the surface of the article 21, an external pressure may be introduced into the upper mold 40, and the outer surface of the plastic film 31 is pressed by the external pressure, and the plastic film 31 is ductile due to heating. Therefore, when the plastic film 31 is subjected to this pressure, any clearance and air existing between the plastic film 31 and the article 21 can be completely eliminated, so that the plastic film 31 is attached to the surface of the article 21 more tightly and evenly.

The external pressure can be arranged on the mold wall of the upper mold 40 as shown in the fourth figure, and the air hole 401 is connected to the outside of the upper mold 40, and when the vacuum system 10 is activated, the plastic film 31 is attached to the article. At the same time as the surface of the 21, external atmospheric pressure is automatically introduced into the upper mold 40 through the air hole 401, and the surface of the plastic film 31 is pressed, and under the double action of internal vacuum and external atmospheric pressure, the plastic film 31 is caused. The surface is closely attached to the surface of the article in conformity with the pressure difference, and any clearance and air existing between the plastic film 31 and the article 21 are completely eliminated.

The external pressure may be as shown in FIG. 5, and an air hole 41 is formed in the mold wall of the upper mold 40. The air hole 41 is connected to a pressure air piping system 45. When the vacuum system 10 is activated, the plastic film 31 and the article are made. After the surface is pasted, the pressurized air piping system 45 is activated, and pressurized air is introduced into the upper mold 40 to pressurize the surface of the plastic film 31, and any gas existing between the surface of the plastic film 31 and the article 21 is removed by gas pressure. Clearance and air make the plastic film 31 more tight The entire sticker is attached to the surface of the article 21.

The external pressure may also be connected to a mechanical pressure device 60 in the upper mold 40 as shown in the sixth figure. The mechanical pressure device 60 has a soft elastic pressing member 61 extending into the mold and inserted into the mold. On the upper surface of the plastic film 31, it is preferable that the soft elastic pressing member 61 has a three-dimensional shape corresponding to the surface of the article 21. After the vacuum system 10 is activated to adhere the plastic film 31 to the surface of the article 21, the mechanical pressure device 60 is activated to cause the pressing member 61 to contact the upper surface of the plastic film 31, and the plastic film is excluded from the plastic film. Any clearance and air between the 31 and the article 21 causes the plastic film 31 to be more closely attached to the surface of the article.

According to the above, the method for attaching a plastic film to a surface of an article comprises the steps of: forming a plastic film into a desired three-dimensional shape according to a surface to be modified by a plastic film; Depending on the shape; in step two, the plastic film formed into a three-dimensional shape and the article are placed in a gas-tight mold capable of achieving a vacuum environment; and in step three, the adhesive layer is heated in the airtight mold to a solid layer of the plastic film from the solid state Turning to a viscose state and making the plastic film malleable; in step 4, the air pressure between the plastic film and the article is reduced to a vacuum state, and the plastic film is attached to the surface of the article with the adhesive layer; 5. Applying an external pressure to the outer surface of the plastic film uniformly, the external pressure may be a soft mechanical pressure or a gas pressure, so that the plastic film can be completely flattened and attached to the surface of the article, and can follow the surface of the article. Degrees, protrusions, recesses, and other irregularities fit snugly.

10‧‧‧ Vacuum system

11‧‧‧ pipeline

12‧‧‧ pipeline

13‧‧‧ switch

14‧‧‧ switch

20‧‧‧Down

21‧‧‧ Items

22‧‧‧Move

30‧‧‧Intermediate space

31‧‧‧ plastic film

311‧‧‧Next layer

312‧‧‧pattern layer

313‧‧‧ plastic layer

314‧‧‧ hardened layer

40‧‧‧上模

401‧‧‧ stomata

41‧‧‧ stomata

42‧‧‧ cavity

45‧‧‧Pressure air piping system

50‧‧‧ heating device

60‧‧‧Mechanical pressure device

61‧‧‧Soft elastic pressure components

The first figure is a schematic view of a plastic film and article of the invention in a device.

The second figure is an enlarged schematic view of the cross-sectional structure of the plastic film of the present invention.

The third figure is a schematic view of the invention in which the plastic film is attached to the surface of the article in a mold by a negative pressure method.

The fourth figure is a schematic view of the invention incorporating a first external pressure in a negative pressure manner to conform the plastic film to the surface of the article in the mold.

The fifth figure is a schematic view of the invention incorporating a second external pressure in a negative pressure manner to conform the plastic film to the surface of the article in the mold.

The sixth figure is a schematic view of the present invention incorporating a third external pressure in a negative pressure manner to conform the plastic film to the surface of the article in the mold.

10‧‧‧ Vacuum system

11‧‧‧ pipeline

12‧‧‧ pipeline

13‧‧‧ switch

14‧‧‧ switch

20‧‧‧Down

21‧‧‧ Items

22‧‧‧Move

30‧‧‧Intermediate space

31‧‧‧ plastic film

40‧‧‧上模

42‧‧‧ cavity

50‧‧‧ heating device

Claims (4)

A method for attaching a plastic film to a surface of an article, comprising: step 1: forming a plastic film into a three-dimensional shape, wherein the three-dimensional shape is defined according to a shape of a surface to be modified by a plastic film; Forming the plastic film into the three-dimensional shape and placing the article in a gas-tight mold capable of achieving a vacuum environment; and in the third step, heating the plastic film in the airtight mold to rotate the adhesive layer of the plastic film from the solid state In a viscose state, and making the plastic film malleable; in step 4, the air pressure between the plastic film and the article is reduced to a negative pressure state, and the plastic film is attached to the surface of the article with the adhesive layer. Step 5, introducing an external pressure into the upper mold, applying a uniform pressure to the surface of the plastic film, excluding the gap and air existing between the plastic film and the article, so that the plastic film is tightly flattened Attached to the surface of the item. A method of attaching a plastic film to a surface of an article as described in claim 1, wherein the external pressure in the fifth step is an atmospheric pressure introduced into the upper mold through the pores provided in the upper mold. A method of attaching a plastic film to a surface of an article as described in claim 1, wherein the external pressure in the step (5) is pressurized air introduced into the upper mold through the air holes of the upper mold. A method of attaching a plastic film to a surface of an article as described in claim 1, wherein the external pressure in step 5 is a mechanical pressure exerted on the surface of the plastic film by extending into the interior of the upper mold. .