JPS5891728A - Polyimide or polyamideimide film having fluorine-treated surface and its bonding - Google Patents

Abstract

PURPOSE:To make a strong adhesive bond, by heat-bonding a poly(amide)imide film having a fluorine-treated surface to a fluorocarbon resin or a metal. CONSTITUTION:A poly(amide)imide film 1 having a fluorine-treated surface is obtained by contacting a poly(amide)imide film 1 with fluorine gas diluted with an inert gas at below 150 deg.C for at least 1min. The fluorine-treated surface 4 is bonded to a flurocarbon resin 2 or a metal 3 and heat-bonded at a temperature >=260 deg.C and a pressure of 0.1kg/cm<2>.G. EFFECT:To heighten the bonding force of a poly(amide)imide film and to give excellent adhesion to metals and fluorohydrocarbon resins. USE:Wire coatings, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to improvements in polyimide or polyamideimide films and improved uses of the films.

Polyamide-imide resin (hereinafter abbreviated as FAI) and polyimide tree BWI (hereinafter abbreviated as PI) are both known polymers with relatively high heat resistance, and polyamide-imide resin has amide bonds and imide bonds in its molecular structure. For example, the reaction between an aromatic diamine having an amide group in its molecule and an aromatic tetravalent carboxylic acid such as pyromellitic acid, and the reaction between an aromatic trivalent carboxylic acid such as trimellitic anhydride and 4-4 - Manufactured by reaction with diamine such as diaminodiphenyl ether, reaction of dibasic acid having an aromatic imide ring in the molecule, and diamine, etc.

On the other hand, polyimide resins are made of, for example, aromatic tetravalent carboxylic acid anhydrides (pyromellitic anhydride, etc.) and aromatic diamines (
Diaminodiphenyl ether, etc.) is a polymer-positioned polymer that has an imide bond in its molecule.

However, when such FAI or PI is bonded to other items, it has the disadvantage of poor adhesive strength.For example, when winding PAI or PI around an electric wire, it is difficult to bond FAI or PI with metal wire. Moreover, if a fluororesin is pre-wound around a metal wire and then PAI or PI is wound on top of that, the adhesive strength with the fluororesin will be low, causing problems in handling and use.

The purpose of the present invention is to improve the adhesive strength of FAI and PI, and this purpose of the present invention is achieved by fluorinating at least one surface of the polyimide or polyamide-imide film.

According to the research of the present inventor, when the surface of FAI or PI film is fluorinated, the adhesive strength is greatly improved, and it exhibits extremely excellent adhesive strength not only to metals but also to fluororesins. became clear.

In the present invention, when fluorinating the surface of an FAI or PI film, it is usually brought into contact with fluorine gas diluted with an inert gas, such as nitrogen gas, at a temperature of about 150" (J or less). Without limitation, the gas may be allowed to stand still in the above gas, or the gas may be allowed to flow.3 The contact time is usually 1 minute or more, preferably 8 minutes or more.In the fluorination treatment, FAI or PI
There is both one surface and both sides of the film, and it is determined as appropriate depending on the purpose of use. For example, the manner in which it is used will be explained using the drawings as follows. In the figure, (1) shows the fluorinated FAI or PI film, (2) shows the fluororesin, (3) shows the metal plate, (4) shows the fluorinated surface, and (a) (b) is for bonding PAI or PI together via fluororesin, (c) is for bonding PAI or PI together, and (c) is for bonding with metal, ( E) is a case where metal and FAI or PI are bonded via a fluororesin.

In addition, (f) shows the case of bonding using FAI8- or PI which has been treated on both sides. Further, as a specific example, the case of covering electric wires is as follows. First, if coating only with fluorinated PI or FAI film, coat with double-sided PI or FAI film.
The surface of the wire is coated with a film, and then a single-sided PI or FAI film is coated on top of the film. Therefore, in this case, the forms ni) and (he) will be used together. In addition, when coating the wire surface 1 with a fluororesin and winding a PI film on it, use the combinations of (a), (a) and (/→ or (a) and (e)). Become.

When a fluorinated FAI or PI film is bonded to a fluororesin or other material, thermocompression bonding is usually used. In the case of a fluororesin, the temperature is above its melting point (for example, in the case of a tetrafluoroethylene-hexafluoropropylene copolymer, about 260 to 280 °C or above), and in the case of a metal, a temperature of about 800 °C or above is sufficient.
The pressure may be less than the pressure at which the material to be bonded 4- is not deformed, for example, OA kg/d (
G) A very slight pressure of the above level is sufficient. In this thermocompression bonding, it is necessary to apply heat and pressure simultaneously. However, in the case of electric wire coating, these films are wound around the metal wire and subjected to heat treatment, and it is thought that pressure is substantially applied during winding.

In addition, as a method of thermocompression bonding with fluororesin, for example, FA
A method of laminating a fluororesin film on the treated surface of I or PI film and bonding it by thermocompression, applying a fluororesin to the same treated surface and bonding it by thermocompression as it is, or applying a treated FA on the coated surface.
Examples include a method of overlapping the treated surfaces of I or PI films and bonding them under heat.

The fluororesin used in the present invention is tetrafluoroethylene alone or a copolymer with other monomers, and other fluororesins include ethylene, propylene,
Polymerizable heptamers such as hexafluoropropylene, perfluoroalkyl vinyl ether, trifluoroethylene, and chlorotrifluoroethylene are used. In addition, chlorotrifluoroethylene alone or a copolymer with other monomers can also be used, and in this case, as the other seven polymers, the same ones as mentioned above can be used.

The fluorinated FAI or PI film of the present invention has high adhesive strength and is used for various purposes, but it is particularly suitable for imparting adhesiveness to fluororesins that have poor adhesiveness, and is also suitable for other purposes such as covering electric wires. It is also preferable.

The present invention will be explained in more detail by showing Examples and Comparative Examples below.

Example 1 P in a polyethylene container having a gas inlet and an outlet
Insert an I film (DuPont's "Kapton" vertical IOO silk x width 5 Q am x thickness 25 AU+), and introduce fluorine gas diluted to 10% (volume) with nitrogen gas from the above inlet at room temperature for 5 minutes and exhaust. It was discharged from the outlet and subjected to fluorination treatment. This film is called film A. Further, after stopping the introduction of the fluorine gas, the sample was left as it was for 25 minutes. This film will be referred to as film B. The treated surfaces of film A and the treated surfaces of film B were joined together at 400°C.
5 was pressed for 2 minutes under the conditions of 9/d (G>).The adhesive strength in the case of film A was 800 to 500 f/1M,
B was 500-8009/14. The adhesive strength was measured by 180°C peel strength.

On top, a tetrafluoroethylene-hexafluoropropylene copolymer (molar ratio 85:15, particle size 0.2~
The thickness of the organic solvent dispersion (0.4 μm) after drying is 2 to 5.
It was applied to a thickness of μm and dried. Next, place the treated side of film A or film B on top of this and
, 5 & 9/ff for 1 minute. The adhesive strengths of the obtained products were as follows: 7-.

Film A 500-100 (1/ff film 8
1000-200 (1/[Example 8 Each treatment of films A and B of Example 1 above, 40
Heat pressing was carried out for 1 minute at 0°C and 5 kq/d.

The respective adhesive strengths are as follows.

Film A 2000g73 or more Film B
)l Nol Example 4 A copper plate (thickness Q, 5 s+ag) was sandwiched between the treated surfaces of the films A and B of Example 1 above at 400°.
Heat pressed on C25 at 9/4 for 1 minute. The respective adhesive strengths are as follows.

Film A 500-700g/cII4 Film B 600-1000f/ffi8- Comparative Example 1 Two layers of PI film that has not been fluorinated 400g
Heat pressing was carried out for 40 minutes under the conditions of °C x 6ky/d.

The adhesive force at this time was almost 0.

Comparative Example 2 Same PI used in Example 1 without fluorination treatment
The same copolymer dispersion as in Example 2 was sprayed onto the film and dried to form a film of 2 to 5 microns. Layer rice-treated PI film on top of this film and
．． When hot pressed for 80 minutes under the respective conditions of 800°C and 10 to 9/ctA, the former had an adhesive strength of 2 Q/7 cm or less, and the latter had an adhesive strength of 50 to 100 P/as.Comparative Example 8 Implemented on rice-treated PI film 25 of the same copolymer as Example 8
Layer the μm film, and then layer the rice-treated PI film on top, aOOoOX 5kg/cd, aOOoOX
They were hot pressed for 80 minutes under the conditions of 10 kg/ctl, and the adhesive strength of the former was 2° to 50°
y/l was thin, and the latter was 100 to 200 y/l.

Comparative Example 4 The copper plate used in Example 4 was sandwiched between the films used in Example 1 which were not subjected to fluorination treatment, and the same treatment as in Example 4 was carried out. The adhesive strength was almost 05.

[Brief explanation of the drawing]

The drawing shows a form of adhering the fluorinated polyimide or polyamideimide resin film of the present invention to other substrates, where (1) is the fluorinated polyimide or polyamideimide resin film, and (2) is the fluorinated polyimide or polyamideimide resin film. Resin, (3
) indicates a metal plate, and (4) indicates a fluorinated surface. (And more) Agent: Eiji Saegusa 11- Ci1 (Dn()＼) l22 Cfu2 (hen)

Claims (1)

[Claims] ■ A polyimide or polyamide-imide film in which at least one surface is fluorinated. (2) A method for adhering a polyimide or polyamide-imide film and a fluororesin, which comprises bringing the treated surface of a polyimide or polyamide-imide film, at least one of which has been fluorinated, into contact with a fluororesin and bonding the film by thermocompression. (2) A method for adhering a polyimide or polyamide-imide film to a metal, which comprises bringing the treated surface of a polyimide or polyamide-imide film, in which at least one surface has been fluorinated, into contact with the metal and bonding the film by thermocompression.