KR20190122364A - Manufacturing method for polyimide composite sheet - Google Patents

Abstract

Disclosed is a method for manufacturing a polyimide composite sheet. The method for manufacturing a polyimide composite sheet comprises the following steps: performing a corona treatment and a first flame treatment on a polyimide film; applying an adhesive on the corona treated and first flame treated polyimide film; performing a second flame treatment on a silicon sheet; and stacking and compressing the second flame treated silicon sheet on the polyimide film coated with the adhesive so that the second flame treated surface faces the surface coated with the adhesive. The polyimide composite sheet prepared by the method of the present invention can be repeatedly compressed and no foreign matter remains or is torn after the compression. In addition, the winding phenomenon and the separation phenomenon do not appear.

Description

Manufacturing method for polyimide composite sheet

A method for producing a polyimide composite sheet.

Adhesives used in electronic packaging are classified into films and pastes according to their use forms, and are classified into conductive, anisotropic and nonconductive adhesives depending on the presence of conductive particles. Generally, it is divided into anisotropic conductive film (ACF), anisotropic conductive paste (ACP), non-conductive film (NCF) and non-conductive paste (NCP). do.

In particular, the connection method between electronic components using an anisotropic conductive film is an environmentally friendly process that replaces the conventional soldering process, and has an advantage of enabling an extremely fine electrode pitch since electrical connection is made using fine conductive particles. .

Thanks to these advantages, anisotropic conductive films are expanding their applications in the packaging of smart cards, LCDs, PDPs, organic ELs, display packaging, computers, mobile phones, automotive navigation, automotive fingerprint sensors, and communication systems. .

The anisotropic conductive film generally includes a thermosetting resin and conductive particles that are cured by heat. Therefore, when connecting two media using an anisotropic conductive film, since a constant temperature, pressure and time should be given due to the characteristics of the thermosetting resin, a method of thermocompressing the contact surface by thermocompression means was used. At this time, a cushioning sheet is used in order to prevent damage of the to-be-compressed part and parts other than a to-be-compressed part by a thermocompression bonding means.

Teflon sheet is used as a conventional buffer sheet, but there is a problem that can not be used in the same point repeated crimping due to the lack of restoring force only one crimping.

Another cushioning sheet is a carbon-containing silicon sheet that can be repeatedly compressed repeatedly, but there is a problem that the foreign matter remains or tears well after pressing.

Another buffer sheet is a composite sheet coated with a silicone resin on one side or both sides of a high heat-resistant polyimide film, the composite sheet has a problem that the winding phenomenon and separation phenomenon, the media to be connected or shake There is a problem in one direction.

Republic of Korea Patent Publication No. 10-2005-0017324

The present invention is to solve a number of problems, including the above-described problems, it is possible to repeat multiple compression, the foreign material does not remain or torn after the compression, the manufacturing method of the novel polyimide composite sheet is suppressed the winding phenomenon and separation phenomenon To provide. However, these problems are illustrative, and the scope of the present invention is not limited thereby.

According to one aspect, performing a corona treatment and a first flame treatment on the polyimide film;

Applying an adhesive on the corona treated and first flame treated polyimide film;

Performing a second flame treatment on the silicon sheet; And

Stacking and compressing the second flame treated silicon sheet on the polyimide film coated with the adhesive such that the second flame treated surface faces the surface coated with the adhesive;

Disclosed is a method for producing a polyimide composite sheet.

The adhesive may be a silicone adhesive.

The silicone adhesive may comprise a thermally conductive material.

The thermally conductive material may be graphite, carbon nanotubes, silver, copper, aluminum, alumina, boron nitride, aluminum nitride, silicon nitride, polyethylenedioxythiophene (PEDOT), polystyrenesulfonate (PSS), polyaniline, polypyrrole, or a combination thereof. Can be.

The pressing may be performed at a pressure of 3 MPa to 5 MPa.

The method of manufacturing the polyimide composite sheet may further include a heat treatment step.

The heat treatment step may be performed at the same time as the pressing step or after the pressing step.

The heat treatment may be performed at a temperature of 120 ℃ to 180 ℃.

Polyimide composite sheet prepared by the method for producing a polyimide composite sheet according to an embodiment of the present invention is capable of repeated repeated pressing, the foreign material does not remain or tear after pressing, there is an effect that the winding phenomenon and separation phenomenon does not appear. .

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

The terms "comprise" or "including" in this specification mean that there is a feature or component described in the specification, and do not preclude the possibility of adding one or more other features or components.

The terms first, second, etc. used herein may be used to describe various components, but the components should not be limited by the terms. The terms are only used to distinguish one component from another.

According to one aspect of the invention, the method for producing a polyimide composite sheet, the step of performing a corona treatment and a first flame treatment on the polyimide film, applying an adhesive on the treated polyimide film, silicone Performing a second flame treatment on the sheet, and laminating the second flame treated silicone sheet on the adhesive-coated polyimide film such that the second flame treated surface faces the surface coated with the adhesive. And heat pressing.

Hereinafter, each step will be described in more detail.

First, a corona treatment and a first flame treatment are performed on the polyimide film. The thickness of the polyimide film is not particularly limited, but may be, for example, 25 μm to 50 μm. The hardness and restoring force of the polyimide composite sheet to be manufactured in the thickness range can be easily controlled.

The surface of the polyimide film is roughened by the corona treatment, which may serve to improve adhesion to the adhesive applied in the next step. Corona treatment may be performed at a speed of 5M / min with an output of 100W to 200W, but is not limited thereto.

The surface of the polyimide film is heated by the first flame treatment, which may serve to improve adhesion to the adhesive applied in the next step. By the 1st flame treatment, the temperature of the surface of a polyimide film can rise to 40 degreeC-100 degreeC (for example, 60 degreeC-80 degreeC).

An adhesive is then applied onto the corona treated and first flame treated polyimide film. The adhesive is not particularly limited as long as it is an adhesive capable of bonding the polyimide film and the silicone sheet. For example, the adhesive may be a silicone adhesive having excellent heat resistance. The silicone adhesive may comprise a thermally conductive material to transfer heat from the thermocompression tool to the anisotropic conductive film upon thermocompression of the anisotropic conductive film. The thermally conductive material is not particularly limited, but for example, graphite, carbon nanotubes, silver, copper, aluminum, alumina, boron nitride, aluminum nitride, silicon nitride, polyethylene dioxythiophene (PEDOT), polystyrene sulfonate (PSS), Polyaniline, polypyrrole or combinations thereof.

Apart from the polyimide film, a second flame treatment is performed on the silicon sheet. The thickness of the silicon sheet is not particularly limited, but may be, for example, 150 μm to 350 μm. The hardness and restoring force of the polyimide composite sheet to be manufactured in the thickness range can be easily controlled.

The surface of the silicon sheet is heated by the second flame treatment, which may serve to improve adhesion to the adhesive contacted in the next step. By the second flame treatment, the temperature of the surface of the silicon sheet may rise to 40 ° C to 100 ° C (for example, 60 ° C to 80 ° C).

The second flame-treated silicon sheet is laminated on the polyimide film to which the adhesive is applied so that the second flame-treated surface is in contact with the surface to which the adhesive is applied, and then pressed. The pressure at the time of the pressing is not particularly limited, but may be performed, for example, at a pressure of 3 MPa to 5 MPa. Within the pressure range, the adhesion between the polyimide film and the silicon sheet may be further improved. In addition, at least a portion of the surface of the polyimide film and / or the surface of the silicon sheet may be melted within the pressure range, which may further improve the adhesion between the polyimide film and the silicon sheet.

Method for producing a polyimide composite sheet according to an embodiment of the present invention may further comprise a heat treatment step. Curing of the adhesive may be promoted by the heat treatment. The heat treatment may be performed simultaneously with the pressing step, or may be performed after the pressing step. The heat treatment temperature is not particularly limited, but may be, for example, 120 ° C to 180 ° C.

The polyimide composite sheet manufactured by the method for preparing a polyimide composite sheet according to an embodiment of the present invention has excellent adhesion between the polyimide film and the silicon sheet, and thus the polyimide film and the silicon sheet are not separated even after repeated repeated pressing. And, after pressing, there is an excellent effect that no foreign matter remains or tears, and the winding phenomenon and the separation phenomenon do not appear.

Hereinafter, a method for producing a polyimide composite sheet according to one embodiment of the present invention will be described in more detail. However, this is presented as a preferred example of the present invention, and in no sense can be construed as limiting the present invention.

Example

Example 1

A polyimide film (manufacturer: SK Konglon PI, trade name: GF200) having a thickness of about 25 μm to about 50 μm was formed using a corona surface treatment machine (manufacturer: Enercon, device name: COMPAK 2000) at 5M with an output of about 100 W to about 200 W. After corona treatment at a rate of / min, the first flame treatment was performed at a temperature of about 60 ° C to about 80 ° C using a flame surface treatment machine (manufacturer: Enercon, equipment name: COMPAK 1000).

A silicon sheet (manufacturer: TIDEL, trade name: TPS) having a thickness of about 25 μm to about 50 μm was subjected to second flame treatment at a temperature of about 60 ° C. to about 80 ° C. using the flame surface treatment machine.

After the adhesive (manufacturer: Shin-Yetsu, brand name: RBL-9110) was apply | coated on the corona treatment and the 1st flame-treated polyimide film, the 2nd flame-treated silicon sheet was laminated | stacked on it, and it crimped at the pressure of 4 MPa. Thereafter, the compressed sheet was heat-treated at a temperature of about 120 ° C. to about 180 ° C. to prepare a polyimide composite sheet.

Comparative Example 1

A polyimide composite sheet was prepared in the same manner as in Example 1, except that the first flame treatment and the second flame treatment were not performed.

Comparative Example 2

A polyimide composite sheet was prepared in the same manner as in Example 1, except that the second flame treatment was not performed.

Evaluation Example 1 Repeated Compression Test

For the polyimide composite sheets prepared in Examples 1 and Comparative Examples 1 and 2, using a crimping tool (temperature of the upper tool: about 400 ° C., temperature of the lower tool: about 90 ° C.) at a pressure of 3.5 MPa for 10 seconds. After repeatedly compressing one section, it was visually observed whether the silicone sheet was separated from the polyimide film, and the results are shown in Table 1. When the silicone sheet is not separated from the polyimide film, it is indicated by ⊙, and only a part of the silicone sheet is separated by ○, and completely separated by ×.

Number of crimps 1 time 10th 30 times 50 times Example 1 ⊙ ⊙ ⊙ ⊙ Comparative Example 1 ⊙ × × × Comparative Example 2 ⊙ ⊙ ○ ×

As can be seen from Table 1, in the polyimide composite sheet of Example 1, the silicon sheet is not separated from the polyimide film even after 50 compressions, whereas in Comparative Example 1 after 10 compressions, Case After 50 compressions, the silicone sheet was completely separated from the polyimide film.

Evaluation Example 2: Expansion Test

For the polyimide composite sheets prepared in Examples 1 and Comparative Examples 1 and 2, using a crimping tool (temperature of the upper tool: about 400 ° C., temperature of the lower tool: about 90 ° C.) at a pressure of 3.5 MPa for 10 seconds. After repeatedly compressing one section, the expansion accuracy was confirmed, and the results are shown in Table 2. Test results were marked as good (⊙) or bad (×). The expansion test is to confirm the expansion and direction of expansion of the electronic component lead wires connected during thermal compression. When the sheet is shaken during thermocompression, the lead wire does not expand or expands in an oblique direction, in which case the expansion accuracy is evaluated to be poor. If the sheet does not shake during thermocompression, the lead wire expands in a linear direction, and in this case, the expansion accuracy is evaluated to be excellent.

Number of crimps 1 time 10th 30 times 50 times Example 1 ⊙ ⊙ ⊙ ⊙ Comparative Example 1 ⊙ × × × Comparative Example 2 ⊙ ⊙ × ×

As can be seen through Table 2, the polyimide composite sheet of Example 1 does not shake the silicon sheet even after 50 compressions, after 10 compressions in Comparative Example 1, after 30 compressions in Comparative Example 2 It can be seen that the silicon sheet is shaken.

Evaluation Example 3: Release Test with Anisotropic Conductive Film

For the polyimide composite sheets prepared in Example 1 and Comparative Examples 1 and 2, one section was repeatedly used at 3.5 MPa using a crimping tool (temperature of the upper tool: about 400 ° C., temperature of the lower tool: about 90 ° C.). After pressing for 10 seconds under pressure, it was visually observed whether the sheet was well separated from the anisotropic conductive film (manufacturer: H & S, trade name: TGP series), and the results are shown in Table 3. Test results were marked as good (⊙), normal (○) or bad (×).

Number of crimps 1 time 10th 30 times 50 times Example 1 ⊙ ⊙ ⊙ ○ Comparative Example 1 ⊙ ○ × × Comparative Example 2 ⊙ ⊙ ○ ×

As can be seen through Table 3, the polyimide composite sheet of Example 1 maintains the releasability with the anisotropic conductive film even after 50 times of compression, while in the case of Comparative Example 2 after 30 times of pressing in Comparative Example 1 After 50 compressions, it can be seen that the release property with the anisotropic conductive film cannot be maintained.

From the evaluation results, the polyimide composite sheet prepared by the method for producing a polyimide composite sheet according to an embodiment of the present invention has excellent adhesion between the polyimide film and the silicone sheet, and excellent expansion accuracy of the silicone sheet, It can be confirmed that the releasability with the anisotropic conductive film is excellent.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (7)

Performing a corona treatment and a first flame treatment on the polyimide film;
Applying an adhesive on the corona treated and first flame treated polyimide film;
Performing a second flame treatment on the silicon sheet; And
Stacking and compressing the second flame treated silicon sheet on the polyimide film coated with the adhesive such that the second flame treated surface faces the surface coated with the adhesive;
Including, polyimide composite sheet production method.
The method of claim 1,
The adhesive is a silicone adhesive, a method for producing a polyimide composite sheet.
The method of claim 2,
Wherein said silicone adhesive comprises a thermally conductive material.
The method of claim 3,
The thermally conductive material is graphite, carbon nanotubes, silver, copper, aluminum, alumina, boron nitride, aluminum nitride, silicon nitride, polyethylenedioxythiophene (PEDOT), polystyrenesulfonate (PSS), polyaniline, polypyrrole or a combination thereof. , Polyimide composite sheet production method.
The method of claim 1,
The pressing is carried out at a pressure of 3MPa to 5MPa, a method for producing a polyimide composite sheet.
The method of claim 1,
Further comprising a heat treatment step,
Wherein the heat treatment step is carried out at the same time as the pressing step, or after the pressing step, a method for producing a polyimide composite sheet.
The method of claim 6,
The heat treatment is carried out at a temperature of 120 ° C to 180 ° C, a method for producing a polyimide composite sheet.