JPS6184380A - Formation of conductive oxide tin film on base body - Google Patents

Abstract

PURPOSE:To form a transparent oxide tin film having small electric resistance on a conductor by applying a soln. of the mono org. tin oxycarboxylate polymer expressed by the specific general formula on the surface of a heated base body consisting of glass, etc. CONSTITUTION:The base body consisting of glass, ceramics, metal, etc. is heated to and held at about 400-700 deg.C and the soln. of the mono org. tin oxycarboxylate polymer expressed by the general formula (in which R; an alkyl group or aryl group, R'; a substd. or non-substd. alkyl group or aryl group, m; 0 or >=1integer) is spray-coated on the surface thereof. The base body is straightly put into a heating furnace and the coating is thermally decomposed at about 500-600 deg.C to form quickly the transparent conductive oxide tin film on the surface of the base body. The above-mentioned soln. is used by dissolving the above-mentioned polymer into a solvent such as alcohol or hydrcarbon at about 10-80wt% and adding further an adequate amt. of dopant such as NH4F thereto according to need.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for forming a conductive tin oxide film on the surface of a substrate such as glass.

Conventional technology Tin chloride such as stannic chloride, organic tin chloride, dibutyltin diacetate,
It is known to oxidatively decompose an organotin compound such as dibutyltin oxide to form a conductive tin oxide film.

Problems to be Solved by the Invention However, in the method using tin chloride, cloudiness occurs in the film due to the chlorine compound, and high electrical resistance is still exhibited between the film and the substrate. In the method using dibutyltin diacetate, the film formation rate is slow, resulting in a non-uniform film, resulting in loss of transparency, and the film exhibits high electrical resistance. In the method using dibutyltin oxide, this compound is insoluble in any solvent, so it cannot be used in the most practical film forming methods such as spraying and dipping. There is also a known method (Japanese Patent Publication No. 53-25331) in which various fluorides are added as dopants to the above organic tin compound to reduce the electrical resistance of the coating to some extent, but even with this method, the electrical resistance of the coating is sufficiently reduced. , and the film formation rate cannot be improved.

As a result of continuing research on forming conductive tin oxide films using various organotin compounds, the present inventors have developed a compound that can quickly form a transparent film and provide a conductive tin oxide film with low electrical resistance. They discovered this and completed the present invention.

In other words, the present invention applies to the surface of a substrate such as heated glass.

General formula % Formula % (In the formula, R is an alkyl group or an aryl group f, R1 is a substituted or unsubstituted alkyl group or an aryl group, tn is ○
A method for forming a conductive tin oxide film on a substrate, characterized by applying a solution of a monoorganotin oxycarboxylate polymer represented by (or an integer of 1 or more).

Furthermore, the present invention provides a substrate characterized in that a solution containing one or more of the monoorganic tin oxycarboxylate polymer represented by the above general formula (II) and a dopant is applied to the surface of a heated substrate such as glass. This is a method for forming a conductive tin oxide film.

The monoorganotin oxycarboxylate polymer used in the present invention has the following general formula [■]: a positive dimer of 1 m-1 when m-Q, and a four-dimensional dimer when m: 2. mer, -m- represents a compound defined as a multimer.

In general formula CI), R is a methyl group or an ethyl group.

Propyl group, butyl group, amyl group, hexyl group.

An alkyl group such as an octyl group, and R1 is a methyl group.

Ethyl group, propyl group, butyl group, t-butyl group 1.1
- Substituted or unsubstituted alkyl groups such as dimethylpropyl group, pentyl group, hexyl group, octyl group, nonyl group, decyl group, undecyl group, dodecyl group, tridecyl group, pentadecyl group, heptadecyl group, phenyl group, tolyl group, etc. The following aryl groups are mentioned.

Another dopant used in the present invention is 7 such as NH4F, HF, 0F3COOH, 05F7
000H.

CF3CO2C2H5, CF2(COOC2H5)2.
cH2FcoNH2゜CBrFx + Fluorine compounds such as trifluoroacetic anhydride, 5bce3.5b (oc
n3) 3.5b (ococa3) 3°5b (oc4a9
)2y, 5b(003H,)2ce, 5b(004H
9) Examples include antimony compounds such as 3°(C6H5)3Sb.

The solvent used in the present invention is one that dissolves the monoorganotin oxycarboxylate polymer represented by the above general formula 〇〕 and the dopant, and easily evaporates when sprayed or dabbed, such as methanol, ethanol, isopropanol, etc. , alcohols such as ethyl cellosolve and butyl cellosolve, methyl ethyl ketone, acetone,
Ketones such as methyl isobutyl ketone, hydrocarbons such as toluene, xylene, solvent naphtha, hexane, heptane, methylene chloride, 1.1. , halogenated hydrocarbons such as 1-trifluoroethane, trifluorotrichloroethane, trichlorethylene, and tetrachloroethylene, esters such as ethyl acetate, propyl acetate, and ethyl lactate, and ethers such as di-n-butyl ether and diethylene glycol dimethyl ether. can be mentioned.

The present invention is carried out as follows.

For example, for glass, the two surfaces are thoroughly degreased and cleaned, the solution of the present invention is spray applied to the surface heated and maintained at a temperature of 400 to 700 C below the softening point of the glass, and the solution is directly heated in a heating oven at 500 to 60 C (lc). ) to form a tin oxide film.

The content of the monoorganic oxycarbo-6-xylate polymer of the present invention in the solution varies depending on the film thickness, but is suitably 10 to 80% by weight.

In addition, in the case of using a dopant to increase the conductivity of the tin oxide film in the present invention, the amount of the dopant to be used can be changed depending on the resistance of the film, but the amount of the dopant to be used is relative to the monoorganic tin oxycarboxylate polymer of the present invention. A weight ratio of 10 to 100 is appropriate.

Effect: According to the method of the present invention, there are many Sn-0-Sn bonds in two molecules, and the structure is similar to that of tin oxide (SnO2), so the formation of tin oxide films at high temperatures is extremely difficult. It is carried out quickly and a uniform transparent film is formed.

This phenomenon is similarly observed when a dopant is also used. If the film formation is slow, the film becomes cloudy or non-uniformly crystallized, making it impossible to obtain a transparent and uniform film. Such effects cannot be found with the use of conventional organotin compounds.

According to the present invention, it is possible to form a film of conductive tin oxide with low electrical resistance on the surface of a substrate such as glass, ceramics, metal, etc., so it is possible to form a film of conductive tin oxide with low electrical resistance. It can be used for electrodes for solar cells, etc.

Next, the present invention will be explained with reference to production examples and examples, where the term "during production" refers to weight.

Production Example 1 166.7 F (1 mol) of monomethyl i acid and 200 ml of benzene were placed in an 11-sized medium-sized flask equipped with a stirrer, two-separating furnace, a thermometer, and a three-azeotropic dehydrator with a reflux condenser.
of acetic acid under reflux while stirring.
67 mol) was added dropwise over 30 minutes.

Reflux dehydration was continued for 2 hours, and 2371ne of water was collected.

After the reaction was completed, the solution was filtered, and benzene was distilled off from the filtrate to obtain 241 white solids (yield: 99.3%). The result of analyzing this thing.

Actual value Calculated value Tin content: 487 coefficient 48.9 coefficient Acid value: 352 It was confirmed from the 355 infrared absorption spectrum that it was monomethyl tin oxyacetate (trimer).

Production Example 2 In the same reaction vessel as Production Example 1, 20% of mono-n-butylstannic acid was added.
Prepare 8.8y (1 mol) and 5oome of toluene,
While stirring, add 9 oy (1.5 mol) of acetic acid to 3 ml under reflux.
It was dropped in 0 minutes. Continue reflux dehydration for 2 hours, and remove water by 22.
3mJ was captured. After the reaction was completed, the solution was filtered and toluene was distilled off from the furnace solution to obtain white solid 275y (99.5%). The result of analyzing this thing.

Actual value Calculated value Tin content: 42.8 43.0
Acid value: 303 305 It was confirmed from the infrared absorption spectrum that it was mono-n-butyltin oxyacetate (tetramer).

Production Example 3 In the same reaction vessel as Production Example 1, 264.9y (1.0 mol) of mono-n-monooctylstannic acid and 300tr of benzene were added.
Add 288% of octylic acid under reflux while stirring.
．． 4f/(2 mol) was added dropwise over 30 minutes. Reflux dehydration was continued for 2 hours, and 26.8"g of water was collected. After the reaction was completed, the solution was filtered, and benzene was distilled off from the filtrate to obtain 525.2y of white solid (99.8 section). .The result of analyzing this thing.

Actual value Calculated value Tin content: 22.3% 226%
Acid: 214 213 From the infrared absorption spectrum, it was confirmed that it was mono n-octyl oxyoctoate (dimer).

Production Examples 4 to 7 In the same reaction vessel as in Production Example 1, the monoorganic stannic acid and organic carboxylic acid shown in Table 1 below were reacted in respective moles.

The same reaction operation and analysis as in Production Example 1 were carried out to obtain a monoorganotin oxycarboxylate polymer.

Table 1 Examples 1 to 8 and Comparative Examples 1 to 3 The surface of the glass plate was heated to 580°C, and then the following box 2 was heated.
A solution having the composition shown in Table 1 (Example) and Table 2-2 (Comparative Example) was heated to an air pressure of 25 m2 + 40 cm from a glass plate.
The tin oxide film was formed by spraying on the surface for 3-4 seconds at a distance of . The state of the obtained tin oxide film was observed, and the film thickness, visible light transmittance, and electrical resistance were measured.

The results are shown in Tables 2-1 and 2-2.

Claims (2)

[Claims] (1) On the surface of a heated substrate such as glass, there is a general formula ▲ mathematical formula, chemical formula, table, etc. , m is 0 or 1
A method for forming a conductive tin oxide film on a substrate, the method comprising applying a solution of a monoorganotin oxycarboxylate polymer represented by the following integers. (2) On the surface of a heated substrate such as glass, there is a general formula ▲ mathematical formula, chemical formula, table, etc. , m is 0 or 1
A method for forming a conductive tin oxide film on a substrate, the method comprising applying a solution containing one or more monoorganotin oxycarboxylate polymers represented by the above integers) and one or more dopants.