CN1327958A

CN1327958A - Frosting chemical for silicate glass

Info

Publication number: CN1327958A
Application number: CN 00110528
Authority: CN
Inventors: 张鸿福; 齐向阳
Original assignee: Individual
Current assignee: Individual
Priority date: 2000-06-11
Filing date: 2000-06-11
Publication date: 2001-12-26
Anticipated expiration: 2020-06-11
Also published as: CN1132795C

Abstract

A frosting chemical for silicate glass contains 30% concentration solution of sulfuric acid (20-45 wt.%), calcium fluoride (15-45), ammonium hydrogen fluoride (20-35) and solution of alcohool (10-20), and features that the volatilizatino and diffusion of fluoric gas in solution is prevented. Its advantages include no need of high-toxin raw material, high reaction speed, simple equipment, less environmental pollution and high frosting effect.

Description

Silicate glass frosting agent

The invention relates to a formula of a silicate glass frosting agent.

Frosting is a process of chemically corroding glass, and an insoluble reactant is generated by utilizing the chemical corrosion effect of acid on the surface of the glass, and is formed into small particle crystals which are firmly attached to the surface of the glass, so that a semitransparent rough surface is obtained. The hair side scatters incident light and is translucent and hazy.

The frosting agent comprises two types, namely frosting liquid and frosting powder, the existing frosting agent mainly comprisesfluoride, wherein the main component of the frosting liquid is hydrofluoric acid, in addition, fluoride, sulfate and the like are added, and other acids (such as hydrochloric acid, sulfuric acid and the like) are sometimes added to adjust the solubility of a reaction product, and the formula is shown in table 1: TABLE 1 basic formulation of hydrofluoric acid frosting solution

Numbering raw material	L-1	L-2	L-3	L-4	L-5	L-6	L-7	L-8
Numbering raw material	L-1	L-2	L-3	L-4	L-5	L-6	L-7	L-8	Hydrofluoric acid	10	20	40	40.2	46.2	22.1	4.6	12
Ammonium fluoride		30	100	26.8	26.0	23.0			Hydrofluoric acid	10	20	40	40.2	46.2	22.1	4.6	12
Ammonium fluoride		30	100	26.8	26.0	23.0			Ammonium hydrogen fluoride							63.3	40
Potassium sulfate	2						7.3		Ammonium hydrogen fluoride							63.3	40
Potassium sulfate	2						7.3		Ammonium sulfate							1.8
Sulfuric acid							4.6		Ammonium sulfate							1.8
Sulfuric acid							4.6		Hydrochloric acid						37.2
Water (W)	100	50	100	29.1	27.8	17.7	18.3		Hydrochloric acid						37.2

In Table 1, the raw materials of L-1, L-3 and L-8 are in parts by weight, the raw materials of the formulas of L-4, L-5, L-6 and L-7 are in weight percentage, the unit of hydrofluoric acid and water in the formula of L-2 is milliliter, and the unit of ammonium fluoride is gram. The concentration of hydrofluoric acid is typically 40% (wt). The hydrofluoric acid has special requirements in packaging, transportation and storage, which brings inconvenience, and the fluoride is prepared into the solid frosting powder, so that the transportation and storage are more convenient than the hydrofluoric acid. The frosting powder is prepared by adding ammonium sulfate, barium sulfate, potassium sulfate and other additives into fluoride as a main component. When in use, sulfuric acid or hydrochloric acid is added to prepare the frosting solution. The glass product is put in the frosting liquid, the glass product is eroded by hydrofluoric acid generated by the reaction of the frosting powder and acid, and the basic formula of the frosting powder is shown in Table 2

TABLE 2 basic composition of frosting powder and formula for preparing frosting liquid

Numbering raw material		P-1	P-2	P-3	P-4	P-5	P-6
Numbering raw material		P-1	P-2	P-3	P-4	P-5	P-6	Frosting powder	Ammonium fluoride	50	40	100		10
Calcium fluoride					10				Ammonium fluoride	50	40	100		10
Calcium fluoride					10		Potassium hydrogen fluoride (KHF)₂)					25
Ammonium sulfate	5		10			10	Potassium hydrogen fluoride (KHF)₂)					25
Ammonium sulfate	5		10			10	Potassium sulfate					14
Sulfuric acid		10		20	20		Potassium sulfate					14		2
Sulfuric acid		10		20	20		Hydrochloric acid			20			1	2
Water (W)		50	240	100	100	100	Hydrochloric acid			20			1	10

In the formula of P-1, P-2, P-3, P-4 and P-5 in Table 2, the raw materials are proportioned according to parts by weight, ammonium fluoride and ammonium sulfate are in grams in P-6, and sulfuric acid and water are in milliliters. The specific gravity of sulfuric acid is 1.84, and the specific gravity of hydrochloric acid is 1.19.

A large amount of fluorine-containing waste gas is generated in the frosting process, so that the environment is polluted, and personnel and equipment are damaged. In recent years, developed countries have deep knowledge of the harm of fluoride, and have made clear regulations on the concentration of fluoride allowed in the environment, the TJ36-76 of China, the design and health Standard of Industrial enterprises, the maximum allowable concentration of hydrogen fluoride in air is 1mg/m³. In the production process, a sealing device is mainly adopted to prevent waste gas from leaking and exhaust equipment is used for extracting the waste gas, the waste gas and the waste water generated in the frosting process are recovered and purified, and the equipment is complex and is complex to operate.

The invention aims to provide a silicate glass frosting agent which has the advantages of low toxicity of raw materials, convenient transportation and use, capability of preventing volatilization and diffusion of fluorine-containing gas in a solution, low environmental pollution, quick reaction, simple equipment, simple and convenient operation and good frosting effect.

The silicate frosting agent consists of three parts, namely solid fluoride, dilute sulfuric acid solution and absorbent, and the specific solution is as follows (each component is in weight percent): 20-45% of 30% sulfuric acid solution, 15-45% of calcium fluoride, 20-35% of ammonium bifluoride and 10-20% of ethanol solution.

The chemical principle is as follows:

glass with silicate as main component, hydrofluoric acid dissolving silica on its surface and SiO₂Reaction:

SiF₄and (3) continuing the reaction to generate complex fluosilicic acid:

the interaction between fluosilicic acid and hydroxide generated by the hydrolysis of silicate to obtain the fluosilicate:

NaF and CaF formed in the reaction₂And SiF₄And (3) reaction to generate fluorosilicate:

through the reaction process, the glass surface is unevenly eroded to form an uneven and lusterless surface.

Reaction of ethanol with unreacted hydrofluoric acid:

so as to reduce the waste gas generated in the frosting process and reduce the environmental pollution.

The invention has the advantages that:

1. avoids using highly toxic hydrofluoric acid as raw material, and has the advantages of low toxicity of raw material and convenient transportation and use.

2. Because the solution for absorbing the hydrogen fluoride is added and can react with the excessive hydrogen fluoride, the volatilization and the diffusion of the fluorine-containing gas in the solution are prevented.

3. Has the advantages of rapid reaction, simple equipment, simple and convenient operation, environmental pollution reduction and good frosting effect.

The following provides examples of the invention:

the formulation of the silicate glass frosting agent comprises solid fluoride, sulfuric acid solution and absorbent. The ratio of each component is shown in Table 3

TABLE 3 specific composition of the formulations of the present invention

Frosting medicament composition	Example 1	Example 2	Example 3	Example 4
Frosting medicament composition	Example 1	Example 2	Example 3	Example 4	Calcium fluoride	15 kg of	45 kg of	35 kg of	18 kg of
Ammonium hydrogen fluoride	35 kg of	20 kg of	30 kg of	25 kg of	Calcium fluoride	15 kg of	45 kg of	35 kg of	18 kg of
Ammonium hydrogen fluoride	35 kg of	20 kg of	30 kg of	25 kg of	30% sulfuric acid solution	30 kg of	25 kg of	20 kg of	45 kg of
Ethanol solution	20 kg of	10 kg of	15 kg of	12 kg of	30% sulfuric acid solution	30 kg of	25 kg of	20 kg of	45 kg of

Solid fluoride in the above formulation: putting calcium fluoride and ammonium bifluoride (with the fineness of 200 meshes) into a plastic container, slowly adding a sulfuric acid solution, continuously stirring, and simultaneously adding an absorbent-ethanol solution to obtain the silicate glass frosting agent.

Claims

1. The silicate glass frosting agent is characterized by comprising 20-45% of sulfuric acid solution with the concentration of 30%, 15-45% of calcium fluoride, 20-35% of ammonium bifluoride and 10-20% of ethanol solution (in percentage by weight).