JPS6139406A - Transparent conductive film - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to transparent conductive films.

More specifically, it is characterized in that a specific rapeseed coating is provided in the middle to improve the adhesion between the polymer film and the metal or metal oxide.

Conventional technology Conventional glass substrate with indium-tin oxide.

Transparent conductive glass provided with a thin film of tin oxide or the like is used for transparent heating elements, selective light transmitting glass for various display elements, and the like.

These thin films are usually deposited by a method using a vacuum system, such as vacuum evaporation, sputtering, or ion blasting. However, transparent conductive glass has the disadvantage that it is difficult to reduce its weight due to the mechanical strength of the glass and manufacturing constraints, and it is also susceptible to impact. Furthermore, it inherently lacks flexibility, which limits its applicability to nine curved surfaces and its workability.

In order to improve these drawbacks of transparent conductive glass, transparent conductive waves IIK are applied to the surface of polymer films such as polyester.
A method of providing a transparent surface has been studied, and it has come to be widely used in applications such as transparent heating elements, transparent switches, and selective light-transmitting films for various display elements.

However, the transparent conductive corrugated film on the polymer film has poor adhesion to the polymer film and poor chemical resistance and abrasion resistance, so it is used only for limited purposes and is not handled well. There are other issues that require special attention.

Possible reasons for poor adhesion between the polymer film and the transparent conductive coating are as follows.

(1) When forming a transparent conductive film by vapor deposition, sputtering, etc., glass can usually be heated to about 600°C, but polymer films often have a low heat resistance and cannot actually be heated to such high temperatures.

(3) The polymer film may contain low-molecular substances such as polymers, oligomers, and organic solvents, and these low-molecular substances may volatilize in a vacuum system.

(4) Compared to glass, polymer films have poor chemical resistance and are subject to limitations in the cleaning process. For this reason, there is a possibility that the surface is more contaminated than glass.

(5) The surface of a polymer film is less smooth than glass.

In an attempt to improve the adhesion between the polymer film and transparent coating, a curable polymer Ti was applied on the polyester film.
A method for forming a polyester film and preventing the volatilization of oligomers in a polyester film (Japanese Unexamined Patent Publication No. 5.5-144986), which improves the abrasion resistance of a transparent conductive film by forming a harder organic layer on a polymer film. How to do it (4!!P Kaisho 56-
1045(+), a method for improving the adhesion between a transparent conductive film and a polymer film by providing an organosilicon compound between the polymer film and the transparent conductive film (Japanese Unexamined Patent Publication No. 57-159
145), but there is still enough f! Adhesion was not achieved.

Motive of the present invention Generally, in order to measure the adhesion between an organic polymer film and an inorganic transparent conductive wave film, an intermediate layer made of an olophilic compound is provided on both. If the strength is low, the practicality of the resulting transparent conductive film will be limited. That is, a balance of mechanical strength is required for the king of polymer films, intermediate layers, and transparent conductive coatings. In order to obtain the strength of the intermediate layer itself, it is possible to use a curable organic film in the intermediate layer, but this method is insufficient in terms of adhesion. That is, in order to obtain adhesion to inorganic substances, the curable organic film itself must have good adhesion to inorganic substances. for that.

Contains certain additives in the curable organic coating.

The method used is to take advantage of the former feature in terms of mechanical strength, while utilizing the latter effect in terms of adhesion.

In this case, if we focus only on adhesion and increase the blending ratio of additives, the mechanical properties of the curable organic film will be impaired, and if the blending ratio is low, the additives will be diluted and dispersed in the curable organic film. This results in a significant decrease in adhesion.

As a result of various studies, the present inventor has overcome the conventional contradictions and found that by adding a certain amount of a specific additive to the curable organic coating 11H, the adhesion with the transparent tetraelectric coating can be greatly improved. This discovery led to the completion of the present invention.

Summary of the Invention The specific additive in the present invention is a specific titanate coupling agent represented by the general formula R: alkyl group Hm 1-5 .

A specific example of the compound is isopropyl tris (dioctyl pyrophosphate) titanate (trade name: GlenAct 513B, Ajinomoto KK).

Bis(dioctyl pyrophosphate) oxyacetate titanate (trade name Prene-Act 158 B, Ajinomoto KK), bis(dioctyl pyrophosphate) ethylene titanate (trade name Prene-Ac) 258S, Ajinomoto K
K) etc.

The amount added is preferably 2 to 10 percent by weight based on the curable organic film. When the amount added is less than 2%,
The adhesion between the curable organic coating containing additives and the inorganic transparent conductive coating is insufficient, and the advantages of the curable organic coating are diminished if the coating exceeds 9% by weight per ct1a.

Polymeric films suitable for the present invention include substantially transparent polyethylene terephthalate.

Polycarbonate, polysulfone, polyethersulfone, polyethylene, polypropylene.

PVC, acetate, polystyrene.

Polyarylate, polyetheretherketone.

Films made of fluororesin, polyimide, etc. are used.

゛When selecting the curable organic film, any film can be selected as long as it has good adhesion to the polymer film and is sufficiently compatible with the titanate coupling agent of the present invention9. Either a thermosetting organic coating or an ultraviolet curable organic coating may be used.

Examples of resins used for the thermosetting organic film include EBOKI 7 resin, urethane resin, polyester resin, melamine resin, acrylic resin, and urea resin.

Examples of resins used for ultraviolet curable organic coatings include acrylic resins, epoxy resins, and urethane resins.

The thickness of the curable organic film is preferably 1 to 10 μm. If the film is thinner than this, it is difficult to uniformly apply the curable organic film and the adhesion to the transparent conductive film becomes uneven. This is undesirable because it causes a decrease in the flexibility of the curable organic coating and a decrease in the adhesion between the polymer film and the curable organic coating.

The polymer film provided with the curable organic film in the present invention is produced by vacuum deposition method or sputtering method.

A transparent conductive film is formed using an ion blating method or the like. The metal oxide used for the transparent conductive film is In
, O,, day no, etc., or a mixture thereof. Examples of the metal include u, Pt, and Pb.

The transparent conductive film according to the present invention has good adhesion.

A transparent heating element with excellent mechanical strength.

It can be used for applications such as transparent switches and various display elements 9 selective light transmitting films.

This will be explained in detail in Examples below.

Examples Example 1. Comparative Example 1 Melting polysulfone resin manufactured by Union Carbide Co., Ltd. using IAM
A 100 μm film was formed by the method. Next, 5% by weight of the additives shown in Table 1 were added to the solid content of the coating agent described below, and coated on the film using a Mayer bar coater to form a cured film with a thickness of 5 μm, and then dried at 160°C for 5 minutes. , to produce a curable organic film.

The coating agent consists of the following composition.

Epoxy resin (Epo) - YD7019. (Manufactured by Tobu Kasei Co., Ltd.) 21% by weight Melaban resin (Kneepan 22R1 Manufactured by Mitsui Toatsu Chemical Co., Ltd.) 9
ffiffi: percent solvent Kira V7 49 weight percent N-
After that, indium-tin oxide was sputtered onto the curable organic film to form a transparent conductive film.

Sputtering conditions Sputtering equipment High frequency sputtering equipment target Indium tin oxide (tin oxide 5-vk3) Gas type, pressure Argon 5 x 10 Tor
rTransparent conductive film thickness: 500λ Surface resistance: 500 m/square Adhesion of the transparent conductive film was evaluated by the following method.

(1) Cellotape peeling test Cellotape was pasted on the transparent conductive coating and the 180° peeling test was repeated four times. It is determined by the ratio R/- of the surface resistance (R,) before the test and the surface resistance (Et) after the test.

(2) Alkali resistance test Soak in 5X caustic soda solution for 5 minutes.

It is determined by the ratio R/R0 of the surface resistance (Ro) before the test and the surface resistance (R) after the test. The transparent conductive film after the test was observed at 70 times magnification using an optical microscope, and the appearance of the film after the alkali resistance test was evaluated. Second test result
Shown in the table.

In Comparative Example 1, it can be seen that the filterate coupling agent is excellent after the Cellotape peeling test, the alkali resistance test, and the alkali resistance test.

Example 2. Comparative Example 2 Example 1. In Comparative Example 1, the additive was inopropyltris (dioctyl pyrophosphate)/titanate (trade name: Preneac) 58B.

Ajinomoto KK) was fixed and the added TFE was changed to 115.7.15% by weight. Other conditions are as in Example 1. Same as Comparative Example 1. The results are shown in Table 2.

Inopropyltris (dioctyl pyrophosphate)
It can be seen that if the amount of titanate added is too small, good adhesion with the transparent conductive film cannot be obtained, and if it is too large, cracks occur.

Example 3. Comparative Example 3 A commercially available polyethylene terephthalate film (trade name: Diafoil, Diafoil KK) with a thickness of 100 μm was coated with a commercially available two-component urethane coating agent (trade name: Hyclex P, Takera KK) as a curable coating to a thickness of 5 μm. After coating using Mayer Percoater, 100℃, 7
After drying and curing for 0 minutes, a curable organic film was prepared by aging for another 2 days.

The coating agent contains 0゜1, 5.5 per resin solid content.
Bis(dioctylpyrophosphate) ethylene titanate (trade name Preneact 25B)
B, Ajinomoto KK) was added to provide Examples and Comparative Examples.

Other conditions are as in Example 1. Same as Comparative Example 1. Test results 'fr: Shown in the second quadrant.

Example 2. As in Comparative Example 2, the addition of bis(dioctylpyrophosphate) ethylene titanate improves the adhesion to the transparent conductive coating.

Table 1

Claims (1)

[Claims] (1) When a curable organic film made of a polymer is provided on a polymer film and a transparent conductive film made of a metal or metal oxide is formed thereon, the curable organic film is titanate having the following structure. A transparent conductive film characterized by containing 2 to 10% by weight of a coupling agent. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ n=1-5 R: Alkyl group