JPH0446027A - Device for producing flaky glass - Google Patents

Abstract

PURPOSE:To continuously and efficiently obtain a flaky glass by circulating a looped substrate on a circulating line, coating the substrate with a soln. of organometallic compds., drying the coating film in a drying furnace, releasing and collecting the film from the substrate by a collecting means. CONSTITUTION:A circulating line is provided to circulate a looped substrate 3. The substrate 3 is introduced into a soln. of organometallic compds. (e.g. silicon ethoxide), and the substrate 3 is coated with the soln. 1. The substrate 3 is then introduced into an electric furnace 4 to dry the coating film, and the film is shrunk and released. The substrate 3 is then introduced into a suction device 5, hence the released film is sucked and collected, and a flaky glass is obtained. Pure water is sprinkled over the substrate 3 from a sprinkler 7, and the substrate 3 is cleaned by a brush 6, dried by a hot-air dryer 8 and again introduced into the soln. 1.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to glass flakes used in plastic fillers, corrosion-resistant linings or paints. In addition, the flaky glass referred to in the present invention is 5 m in length and width.
It refers to glass flakes with a diameter of m or less.

[Prior Art] Most flake glass is composed of soda lime silicate glass and has a thickness of about 4 μm. It is manufactured by blowing up molten glass like a balloon, rapidly cooling it, and crushing it. With the development of industry, there is a demand for thinner glass flakes with compositions that can withstand higher temperatures, but a method for industrially producing glass flakes that can withstand this demand has not been put to practical use.

Natural mica is known as flakes that are used industrially. Although it has been pointed out that there are problems such as ■high price, ■coloring due to impurities, ■poor durability, and ■no practical electrical conductivity, it is used in various industries because there are no substitutes. It is used.

In addition, as a technique for manufacturing a thin glass plate from a solution containing an organometallic compound, for example, as described in JP-A-51-34219, a solution after hydrolysis and dehydration condensation of an organometallic compound is used. It is known to make thin glass by floating it on other liquids. According to the method described in this publication, it is said that thin glass pieces of 1 μm or less can be obtained, and it can be inferred that glass flakes can be produced by crushing this.

However, this technology has drawbacks such as: ■ It is difficult to collect glass pieces floating in water; ■ It is difficult to achieve a uniform film thickness.
It is practically difficult to industrially produce glass flakes using this technique.

The present inventors first applied a solution containing an organometallic compound onto a substrate with a smooth surface, dried it, and sintered it after removing it from the substrate, thereby easily producing glass flakes. Found that it can be manufactured efficientlyj7
, filed a patent application.

Problems to be Solved by the Invention] The method for producing glass flakes by the present inventors has room for improvement in order to industrially mass-produce stable glass flakes.

Therefore, the purpose of the present invention is to improve the above method of the present inventor,
An object of the present invention is to provide an apparatus for continuously producing glass flakes exhibiting stable physical properties.

[Means for Solving the Problems] In order to achieve the above object, the present invention employs the following configuration.

That is, a means for applying a solution containing an organometallic compound onto a loop-shaped substrate, a means for drying a coated film of the solution containing the organometallic compound, and a means for separating the coated film after drying from the loop-shaped substrate. means for collecting flakes that are
This is an apparatus for producing glass flakes, in which the loop-shaped substrate forms a circulating conveyance path in which the loop-shaped substrate sequentially passes through the coating means, drying means, and collection means.

The organometallic compound used in the present invention may basically be any compound as long as it undergoes hydrolysis and dehydration condensation, but metal alkoxides having an alkoxyl group are preferred. More specifically, methoxide, ethoxide, propoxide, butoxide, etc. of silicon, titanium, aluminum, zirconium, etc. are used singly or as a mixture.

The solvent of the solution containing the organometallic compound is substantially
Basically, anything can be used as long as the self-organometallic compound is dissolved, but
Water is required for hydrolysis of the organometallic compounds, most preferably alcohols such as methanol, ethanol, propatool, butanol.

This water may be either acidic or basic, but in order to promote hydrolysis, it is preferable to use water made acidic with hydrochloric acid, nitric acid, sulfuric acid, or the like.

In addition, organic thickeners, etc. may be added to change the properties of the above liquid.However, if the amount added is too large, it may carbonize during the final heating stage, so it should be kept at 1096 or less. It is.

The substrate used in the present invention can be made into a loop!・
Becomes su. Preferred materials that can be processed thinly and have strength are, for example, metals such as stainless steel and aluminum, and plastics such as vinyl chloride and polyethylene, all of which have smooth surfaces. By feeding the substrate belt at a constant speed, glass flakes with highly uniform thickness can be manufactured.

Next, the manufacturing process of glass flakes using the above-mentioned means of the manufacturing apparatus of the present invention will be explained.

Basically, any method may be used to apply the solution to the substrate as long as it can form a thin film of the solution containing the organometallic compound on the substrate. A day/pipe method is preferred, in which the substrate is immersed in a solution and pulled up at a constant speed.

The process of drying the film and substrate after coating is mainly a process for evaporating the solvent, and here the film adhering to the substrate shrinks and peels off.

It is preferable to use separate heating to promote evaporation, but the heating temperature range in this case is approximately 40°C to 500°C, and the heating time is approximately 1 minute to 30 minutes. ]. If drying is carried out at higher temperatures and times, there will be no essential improvement and it will only be a waste of heat sources.

The step of collecting dried flakes is a step of collecting dried flakes on the substrate. Although there are no particular limitations on this method, since the flakes are thin, collection using gas is convenient.

In the apparatus of the present invention, in addition to the above three processes using the coating means, drying means, and collection means, there is no problem in combining various processes. Once the collection is complete, the remaining flakes are completely removed and other stains are removed, and the substrate is ready to be reapplied with the solution.
Preferable from the viewpoint of quality control. Although cleaning depends on the type of substrate, a commonly used cleaning method may be used. Cleaning using detergent and mechanical brushing is simple and effective.

The thickness of the glass flakes produced according to the present invention varies depending on conditions such as the concentration of raw materials during solution or film formation, drying temperature, and moving speed of the substrate, but is generally from 10 μm to 0.0 μm.
The opening is 0.05 μm. If the film thickness is thicker than about 10 μm,
The difference in drying rate between the free surface of the film and the vicinity of the substrate becomes too large, and delamination of the film in a direction horizontal to the substrate occurs. On the other hand, if the film thickness is less than about 0.005 μm, the adhesion between the substrate and the film will be too great, and the film will not peel off from the substrate and will not form flakes.

There are no particular limitations on the method for sintering the peeled film. Further, it is desirable to heat at a sufficient sintering temperature and time to ensure that the peeled film is transformed from gel to glass.

[Function] According to the present invention, thin glass flakes can be easily and easily mass-produced.

[Example code] FIG. 1 shows an apparatus for producing glass flakes.

A solution 1 containing 10,100 ml of commercially available silicone tetramethoxide, 1,000 ml of ethanol, and 1,200 ml of 0.1N hydrochloric acid is prepared in a bathtub 2.

The substrate 3 to which this solution 1 is applied has a width of 30 cm and a thickness of 50 cm.
It is a μm stainless steel belt. This stainless steel belt was fed at a constant speed of 50 cm/min to continuously produce flakes.

The step of forming a film on the substrate is accomplished the moment the substrate 3 is pulled out of the solution 1 into the atmosphere. Drying is performed by passing the substrate 3 through an electric furnace 4 maintained at 80°C.

At this time, the glass flakes are peeled off from the substrate 3. At the same time, the flakes can be collected by means of a device 5 that suctions onto the substrate 3. The flakes collected here were heated to 800°C in an electric furnace (not shown) to form glass flakes. The cleaning and drying of the substrate 3 is performed by a brush 6 that rotates in the opposite direction to the direction in which the substrate travels.

Here, in order to enhance the cleaning effect, a device 7 for spraying pure water is attached. After passing through one or more drying steps in a hot air dryer 8, the substrate 3 is returned to its original state. This equipment made it possible to continuously produce glass flakes.

In addition, this fruit Ii! This example is only an example of the present invention, and the present invention is not limited to this embodiment. [Effects of the Invention] According to the present invention, thin flaky glass, which has been difficult to manufacture in the past, can be produced. can be produced continuously, easily and efficiently.

[Brief explanation of drawings]

FIG. 1 shows an apparatus for producing glass flakes. 1. Solution containing organometallic compound, 3. Substrate, electric furnace, 5
・・Suction device, 6・・Cleaning brush, pure water spray device, 8
hot air drying oven

Claims (1)

[Claims] (1) means for applying a solution containing an organometallic compound onto a loop-shaped substrate; means for drying a coated film of the solution containing the organometallic compound; and a means for collecting the flakes, wherein the loop-shaped substrate forms a circulation conveyance path that successively passes through the coating means, the drying means, and the collecting means. manufacturing equipment.