JPH02145459A - Glass for copying machine and production thereof - Google Patents

Abstract

PURPOSE:To obtain a glass for copying machine having excellent visible ray transmittance, surface resistance, coefficient of static friction, etc., by applying a solution containing specific two kind of chlorine-containing alkoxides to the surface of a glass substrate, drying the solution and calcining the resultant film and then forming a coating film of methyl group-containing organosilicone compound thereon. CONSTITUTION:A solution obtained by blending a chlorine-containing indium alkoxide expressed by formula I (R1 is 2-6C alkyl or alkoxy alkyl; 1.8<=x<=2.7) with a chlorine-containing tinalkoxide expressed by formula II (R2 is 2-6C alkyl or alkoxyalkyl; 2.5<=y<=3.8) at a molar ratio of 87/13<=In/Sn<=96/4 and having 0.015-0.08mol/l concentration is applied to the surface of a glass substrate. Then the coating solution is dried and calcined at 350-550 deg.C to afford a film. Then a solution of methyl group-containing organosilicone compound (e.g. methylmethoxysilane) is applied on the surface of film and dried to provide the glass for copying machine.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for manufacturing copying machine glass used in a document feeding section of a copying machine, particularly an automatic document feeding type copying machine, and more specifically relates to a method for manufacturing glass for a copying machine used in a document feeding section of a copying machine of an automatic document feeding type. The present invention relates to a method for producing copying machine glass that prevents problems caused by static electricity caused by rubbing during feeding, and has excellent surface smoothness and light transmittance.

[Prior Art and Problems to be Solved] Normally, the paper feeding mechanism of an automatic document feeding type copying machine rotates a rubber belt on a glass plate by a pair of rolls for feeding the document and a roll driven in synchronization with the rolls. By doing so, the original is automatically conveyed onto the glass plate.

During normal use, the belt and glass plate are always in close contact with each other, and therefore, when a document is fed, static electricity is generated due to friction between the document and the glass plate, and between the glass plate and the rubber belt. Since it is an insulator, static electricity cannot be removed, and a large amount of static electricity builds up between the glass plate and the rubber belt. This static electricity prevents paper from feeding smoothly, causing problems such as paper jams and poor copying due to dust adhesion. is likely to occur. This tendency is particularly noticeable in high-speed copying machines, and various countermeasures have been taken.

For example, if a glass plate is treated with antistatic treatment,
Japanese Utility Model Publication No. 56-159345 describes a document placement glass for a copying machine, in which a transparent conductive layer is laminated on the light-receiving surface of the glass plate, and this transparent conductive layer is grounded, so that dust charged with static electricity is removed. without adhering to the document placement glass.
It has been shown to ensure that good copies are always obtained. Furthermore, Japanese Patent Application Laid-Open No. 57-90668 discloses that by applying a transparent anti-static treatment to the document placement surface made of transparent glass, defects in document conveyance due to frictional electrification that occur during conveyance of the document or when the conveyance belt runs are prevented. However, these conventional glass surface treatment methods do not satisfy both antistatic effect and surface smoothness at the same time, and are not sufficient as a countermeasure against paper jams.

For these reasons, Toyama Ganjin published Japanese Patent Application Laid-Open No. 63-23302.
No. 0 has an antistatic layer on at least 3 sides of the document feed side of the glass plate or the other side thereof.
A glass for a copying machine characterized by having a thickness of 0.00 to 1500 mm, and a thin surface smooth layer on the paper contacting surface on the document feeding surface side, and a surface smoothing layer having a thickness of 300 to 2000 mm. We disclosed a manufacturing method and proposed glass for copying machines with excellent antistatic effect and smoothness on the surface of glass for copying machines.

Subsequently, the applicant further investigated the optical conditions for producing copying machine glass using the coating method. We considered ways to obtain opportunities.

[Specific Means for Solving Problem c] In view of the problems of the conventional method, the present inventors have conducted intensive studies and found that indium alkoxide and tin alkoxide containing chlorine of a specific chemical composition are added to the glass surface using a specific method. By mixing the mixture in different proportions, applying it, and baking it, and then applying a silane-based chemical solution and drying it, glass for copiers with excellent light transmittance, surface smoothness, and surface resistivity can be obtained. The present invention was achieved by discovering that

That is, the present invention provides chlorine represented by the general formula In(ORI))c C1 or K (where R1 represents an alkyl group or an alkoxyalkyl group having 2 to 6 carbon atoms, and 1.8≦x≦2.7). Containing indium alkoxide and general formula 5n
(ORx)yc1*-7 (R, has 2 to 6 carbon atoms
represents an alkyl group or an alkoxyalkyl group, 2,
The chlorine-containing tin alkoxide represented by 5≦y≦3.8) has an In/Sn molar ratio of 87/13≦In/Sn≦9.
Concentration 0.015-0.08m mixed at a ratio of 674
ol#! A conductive layer coated with a solution of the above composition and a slipping layer coated with a solution of a methyl group-containing organosilicon compound are coated on the surface of a copying machine glass and a glass substrate. A glass for copying machines characterized by coating a chlorine-containing alkoxide, drying and baking at 350 to 550°C to form a film, and coating the surface of the film with a solution of an organosilicon compound containing a methyl group and drying. This is the manufacturing method.

The plate glass used in the present invention may be ordinary plate glass, but chemically strengthened or air-cooled tempered glass is preferably used. Further, it is preferable to use a material having as high a light transmittance as possible, specifically, a material having a light transmittance of 89% or more at a thickness of 41% or less.

When a normal glass plate is used, it can be coated and fired by the method of the present invention, and then made into tempered glass by air cooling.

General formula In(OR,), CI, - used in the present invention
The alkyl group R,,R, in X or Sn(ORz)γCl41 has 2 to 6 carbon atoms, but both are particularly preferably an isopropyl group, a butyl group, or an alkoxyalkyl group such as ethylene glycol monoethyl ether. . The above-mentioned chlorine-containing alkoxide can be used as long as it has a uniform composition and is manufactured by any manufacturing method.After dissolving InCl3.5nC14 in alcohol corresponding to OR, OR2, alkali metal or alkali metal The composition of the present invention may be obtained by adding a specific amount of alkoxide and removing the salt produced (InCl3.5nC1 and In(OR)3.5
It is also possible to mix completely substituted alkoxides such as n(OR)a so as to have the composition of the present invention, and then heat and stir to obtain a uniform composition.

The total concentration of chlorine-containing tin alkoxide and chlorine-containing indium alkoxide in the coating solution of the present invention is 0.
015-0.08+*ol/1 is preferred. If the total concentration of both is less than 0.015 mol/J, the thickness of the coated film is too thin, making it difficult to form a film with uniform thickness, making it impossible to obtain a film with reproducible electrical characteristics. ,on the other hand,
If the concentration exceeds 0.08 mol/1, there is no major change in the electrical properties, but it becomes difficult to obtain a film with a thickness of 800 Å or less, which reduces the transmittance of visible light, which is not preferable.

The conductive film forming composition used in the present invention has a very long pot life, lasting several months or more under normal storage conditions.
The above solution, which has the great advantage of not causing hydrolysis or precipitation, is usually dissolved in the alcohol used to produce the metal alkoxide, but this solution may be further diluted with a solvent. , hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene, and xylene, n-propanol,
Alcohols such as l-propanol, n-butanol, i-butanol, acetate esters such as ethyl acetate and butyl acetate, ketones such as diethyl ketone and acetone, ethers such as ethylene glycol monoethyl ether, THF
After diluting with , chloroform, etc., a film can be formed under various conditions.

The molar ratio of indium and tin in the coating liquid used in the present invention is preferably in the range of 87/13≦In/Sn≦9674.

The lowest value of surface resistance is within the range of the above molar ratio,
As the composition deviates from the minimum value, the surface resistance value gradually increases. On the other hand, the visible light transmittance is I
As n/Sn (molar ratio) increases, it becomes smaller,
The value is almost saturated within the above range.

Therefore, when the In/Sn (molar ratio) is smaller than 87/13, the surface resistance increases, the visible light transmittance decreases,
In particular, the visible light transmittance becomes too low, which is not preferable. When the In/Sn (molar ratio) is greater than 96/4, the visible light transmittance does not change significantly, but the surface resistance value is too large, which is not preferable.

Application methods include spray method, roll coating method,
The film can be formed using screen printing, a spin code method, or a dipping method, and the dipping method or roll coating method is preferable.

Conditions such as temperature and humidity during application greatly affect the rate of hydrolysis, so strict control is required.

After forming a film by the above method, it may be left at room temperature for about 10 minutes to 1 hour, or it may be placed in a heating device as it is and heated to perform drying and baking at the same time.

In the above process, the temperature increase rate is very important, and 1O
By heating slowly within ℃/win, a dense film with excellent optical transparency can be obtained; however, if the heating rate is faster than that, it may cause minute cracks, which is undesirable. By drying and firing within this temperature range, preferably 350 to 550°C, more preferably 450 to 520°C, the alkoxide is completely oxidized and decomposed to have a composition of ITO, and the surface resistance of the film is low. It also has excellent durability. Firing temperature is 35
If the temperature is lower than 0°C, the alkoxide will not completely decompose into an oxide, so the formed film will have poor durability and the surface resistance will not be low enough.
If the temperature exceeds 50° C., the glass serving as the substrate may become distorted, which is not preferable.

By forming the film under the above conditions, the film thickness is 209 to 800 mm.
It becomes an excellent transparent conductive film with high human visible light transmittance.

A solution of an organosilicon compound containing a methyl group is further coated on the surface of the film having the IT composition formed by the method described above and dried to provide a lubricating layer to improve lubricity.

As the organosilicon compound containing a methyl group used in the present invention, any compound containing a methyl group can be used.
Examples include alkoxysilane, chlorosilane, chlorofluorosilane, silanol, silane, silicone isocyanate, fluorosilane, and silicone oil, among which alkoxysilane, silicone isocyanate, silicone oil, and the like are preferred.

Solutions of these organosilicon compounds can be used by dissolving them in various solvents, such as hydrocarbons such as hexane and heptane, aromatic hydrocarbons such as benzene, toluene, and xylene, n-propanol, i-Proper Tools, n
-Alcohols such as phthanol and i-butanol, acetate esters such as ethyl acetate and butyl acetate, diethyl ketone,
After diluting with ketones such as acetone, ethers such as ethylene glycol monoethyl ether, THF, chloroform, etc., it is applied and dried to form a film.

In this case, the concentration of the organosilicon compound is 0.03-0.
8 mol/l is preferable, and the concentration is 0.03 mol/l.
If it is less than 1, the surface lubricity will not be sufficiently improved; on the other hand, if it is less than 0.8 mol/j! If it is larger, the lubricity increases, but the surface resistance value decreases, and a sufficient antistatic effect cannot be obtained. The above solution can be applied by hand coating, spraying, roller coating, screen printing, spin cording, and dipping, but hand coating and roller coating are preferred, especially when forming a slippery film. As a result, it is necessary to form a sufficiently thin film so that the antistatic effect on the surface does not decrease. Therefore, when forming a thin film, a method of soaking the coating solution in absorbent cotton, gauze, etc. and lightly applying it to the surface is recommended. is an advantageous method.

After being applied by such a method, a film having lubricity is formed by drying at a temperature of 60 to 200° C. for 10 minutes or more. If the drying temperature is lower than 60°C, the solvent will not volatilize sufficiently, so the film strength will be weak, and it will peel off or wear easily. On the other hand, if it is higher than 200°C, the lubricity will start to decrease, and the film will not have sufficient lubricity. It will not have.

The copying machine glass obtained by the method described above has a visible light transmittance of 87% or more (500r+n), a static friction coefficient of μs = 0.35 or less, and a surface resistance value of 1000.
KΩ/unit or less, resulting in copying machine glass that has an antistatic effect and has a very high visible light transmittance.

[Example] The present invention will be specifically explained with reference to Examples.

Example I In(0-n-Bu) 2C1 and 5n(04t)a C
1 was adjusted using raw materials and a 1:1 solvent of isopropyl alcohol and 〇-propyl acetate so that In/Sn (molar ratio) = 9515 and the total concentration of both alkoxides was 0.025 mol/l. was used as a coating solution.

Next, a glass substrate of 330 x 480 x
4 (mm) thick float glass was sufficiently washed with a neutral detergent, ceria, etc., and then washed again with pure water and dried before use.

The coating method was performed using a dipping method, and the pulling rate was 0.4.
After pulling it up at a rate of cm/see, the temperature was raised to 500°C over 1.5 hours and baked for 30 minutes. Thereafter, this substrate was naturally cooled to room temperature, and alkoxysilane [Sill(Me)
)(0-Et)2] (concentration 0.2 mol#!) was impregnated into gauze, applied by lightly wiping the surface, and dried at 60°C for 20 minutes to prepare a sample. In the chemical formula of the coating liquid used, nBu represents an n-butyl group, Et represents an ethyl group, and Me represents a methyl group.

Visible light transmittance is 4 using Shimadzu UV365.
Measurements were made in the range of 80 to 7800 II, and the representative value at 500 nm was 89.6% in this case.

The surface resistance value is 5u manufactured by Yokogawa-Hewlett-Packard.
When measured using an rface resistance meter, it was 100 to 500 Ω/mouth.

In addition, the static friction coefficient was determined as follows, i.e., the lower surface is 100 x 100 (am) and the weight is 100 g.
Place a 100 x 100 (-m) copy paper with a weight on it on the copying machine glass, and lift one end at a constant speed of 0.2 cm/sec to separate the stand and the copying machine when the weight starts to slip. From the angle θ of the glass, the static friction coefficient μ5=tan
θ was calculated.

μs = 0.05 to 0.13. The copying machine glass obtained in this example was set in a commercially available copying machine, and A
After making 10,000 copies with the DF device, we measured the visible light transmittance (T), surface resistance (Rs), and static friction coefficient (μS) in the same manner as before the test, and found that T = 89.5 to 8.
8.9%, Rs=200~50QKΩ/mouth, us=O
, 07 to 0.14, which is almost the same as before the test, indicating that the copying machine glass prepared in this example is sufficiently durable.

Examples 2-4 Compositions of indium and tin chlorine-containing alkoxides,
An ITO film was formed on a glass plate in the same manner as in Example 1 by changing the molar ratio, total concentration, and coating method. After coating by various coating methods by changing the coating solution for forming a slippery film. The glass was dried to obtain copying machine glass. Table 1 shows the results of various conditions for each coating liquid in each of these Examples, coating conditions, and physical properties and durability of the glass for a copying machine produced. Regarding durability, we conducted the same test as in Example 1 and measured the visible light transmittance, surface resistance value, and coefficient of static friction, and selected the ones whose values hardly changed and did not pose any problem in use. Items whose values change and cause problems in use are indicated by an x.

Reference Example 1 Using the same plate glass as that used in Example 1, the surface of the glass was sprayed with a commercially available glass cleaner and wiped dry. Table 1 shows the physical properties of the glass.

Comparative Example 1 ~ Composition of chlorine-containing alkoxide of findium and tin,
An ITO film was formed on a glass plate in the same manner as in Example 1 by changing the molar ratio, total concentration, and coating method. After coating by various coating methods by changing the coating solution for forming a slippery film. The glass was dried to obtain copying machine glass. Table 1 shows the results of the various conditions and coating conditions of each coating liquid in each of these Examples, and the physical properties and durability of the prepared copying machine glass. However, in Comparative Example 7, the charged film The firing temperature during formation was 300°C for 130 minutes, and in Comparative Example 8, the drying temperature during formation of the slippery layer was 250°C.

[Effects of the Invention] The copying machine glass of the present invention is an ITO composition metal oxide film prepared using a chlorine-containing alkoxide as a coating liquid, and is an antistatic layer with excellent visible light transmittance. A thin slippery layer coated with a solution of an organosilicon compound containing methyl groups is provided on top, which has excellent visible light transmittance, surface resistance, and coefficient of static friction, making automatic paper feeding possible. Not only can it completely prevent charging during printing, but it also improves the paper's slippage, thereby reliably preventing paper jams.

Claims (2)

[Claims] (1) General formula In(OR_1)_xCl_3_-_x(
However, R_1 represents an alkyl group or an alkoxyalkyl group having 2 to 6 carbon atoms, and chlorine-containing indium alkoxide represented by the formula Sn (1.8≦x≦2.7) and the general formula Sn (
OR_2)_yCl_4_-_y (wherein R_2 represents an alkyl group or alkoxyalkyl group having 2 to 6 carbon atoms, and 2.5≦y≦3.8), the chlorine-containing tin alkoxide has an In/Sn molar ratio 87/13≦In
/Sn≦96/4 concentration 0.015~
A glass for a copying machine comprising a plate glass whose surface is sequentially coated with a conductive layer coated with a solution of 0.08 mol/l and a slippery layer coated with a solution of an organosilicon compound containing a methyl group. (2) On the surface of the glass substrate, the general formula In(OR_1)_
xCl_3_-_x (where R_1 represents an alkyl group or alkoxyalkyl group having 2 to 6 carbon atoms, and 1.8
≦x≦2.7) and a chlorine-containing indium alkoxide with the general formula Sn(OR_2)_yCl_4_-_y
(However, R_2 represents an alkyl group or alkoxyalkyl group having 2 to 6 carbon atoms, and the chlorine-containing tin alkoxide represented by 2.5≦y≦3.8) has an In/Sn molar ratio of 87/13≦ A solution of In/Sn≦96/4 with a concentration of 0.015 to 0.08 mol/l is applied, dried and fired at 350 to 550°C to form a film, and then methyl groups are added to the surface. 1. A method for producing glass for copying machines, which comprises applying a solution of an organic silicon compound therein and drying the solution.