Electrostatic dry enamel acid-resistant glaze

Abstract

The invention relates to the technical field of enamel glazes, and discloses an electrostatic dry process enamel acid-resistant glaze. The mass fraction of each component is as follows: 50-60% of SiO2; 13 to 19% of B2O3; 0.30 to 1.0 percent of CaO; 24 to 8% of TiO2; 5 to 10% of BaO; 8 to 15 percent of Na2O; 3 to 5% of K2O; 1%-5% of CaF2; 0.5 to 1% of CoO; 0.1 to 0.8 percent of CuO; and 0.1 to 1% of NiO. According to the invention, on the premise of ensuring the performances of the adherence, the acid resistance, the porcelain surface and the like of the enamel, the formula structure is adjusted, and the resistivity and the insulativity of the porcelain glaze are increased, so that electrons of the charged powder are not easy to lose, the capacitance of the powder is increased, and the powdering rate of the electrostatic powder is improved.

Description

Technical Field

[0001] The invention relates to the technical field of enamel materials, and more particularly to an electrostatic dry-process enamel acid-resistant glaze material with high powder application rate, good adhesion and good acid resistance. Background Art

[0002] Since the emergence of the electrostatic dry spraying process in the 1970s and 1980s, the enamel industry has ushered in revolutionary progress. The electrostatic dry spraying process has many advantages and has been widely used in the entire enamel industry. The working principle of electrostatic dry powder spraying is that the body is grounded with positive charge, and the high-voltage electrostatic generator in the spray gun generates a negative voltage of 80,000-100,000 volts, which produces a corona discharge phenomenon and ionizes the surrounding air. When the enamel powder is sprayed from the spray gun, it is negatively charged. Under the action of the electrostatic field, it moves to the positive electrode body and is deposited on the body to form a more uniform coating. The advantages of the enamel electrostatic dry process: saving process, no need for drying; easy recycling of powder, high resource utilization; no wastewater and waste gas, green and environmentally friendly; no need to add clay and various grinding additives, the porcelain surface is smooth and delicate, the degree of automation is high, the thickness of the porcelain layer is easy to control, and the stability of product quality can be fully guaranteed. However, the overall powder coating rate of the electrostatic dry powder enamel acid-resistant glaze on the market is not high. During the enamel production process, powder loss is easy to occur, resulting in defects such as a thin porcelain layer, small pits, burning spots, and uneven porcelain surface.

[0003] Therefore, developing an electrostatic dry enamel acid-resistant glaze with high powder coating rate, good adhesion and good acid resistance is a problem that technicians in this field need to solve urgently. Summary of the invention

[0004] In order to solve the problem of low electrostatic powder coating rate, the present invention starts from the design of enamel glaze formula, adjusts the formula structure, increases the resistivity and insulation of the enamel, and ensures that the electrons of the charged powder are not easily lost, increases the capacitance of the powder, and improves the electrostatic powder coating rate, thereby providing an electrostatic dry enamel acid-resistant glaze.

[0005] In order to achieve the above object, the present invention provides an electrostatic dry enamel acid-resistant glaze, the mass fraction of each component is as follows:

[0006] SiO 2 50-60%; B 2 O 3 13-19%; CaO 0.30-1.0%; TiO 2 4-8%; BaO 5-10%; Na 2 O 8-15%; K 2 O 3-5%; CaF 21-5%; CoO 0.5-1%; CuO 0.1-0.8%; NiO 0.1-1%.

[0007] Preferably, the mass fraction of each component is as follows:

[0008] SiO 2 50-55%; B 2 O 3 13-15%; CaO 0.50-1.0%; TiO 2 5-7%; BaO 8-10%; Na 2 O 8-11%; K 2 O 3-4%; CaF 2 2-4%; CoO 0.7-1%; CuO 0.5-0.6%; NiO 0.7-1%.

[0009] Further preferably, the mass fractions of the components are as follows: SiO 2 52.78%; B 2 O 3 14.63%; CaO 0.59%; TiO 2 5.28%; BaO 8.20%; Na 2 O 10.53%; K 2 O 3.59%; CaF 2 2.13%; CoO 0.95%; CuO 0.53%; NiO 0.79%.

[0010] SiO in glaze 2 It is the main component and the main glass network former. SiO 2 The higher the amount, the better the acid resistance. 2 Increasing the content within the range of 50-60% can improve the mechanical strength and hardness of the glaze, and can also improve the acid resistance, chemical stability and thermal stability.

[0011] B in glaze 2 O 3 It is not only a solvent for enamel, but also a network former for enamel, which promotes the formation of glass phase at low temperature. 2 O 3 The increase of content will increase the mechanical strength of the glaze and improve its wear resistance. 2 O 3 It has a good fluxing effect and can reduce the softening temperature, viscosity, surface tension and expansion coefficient of porcelain glaze.

[0012] CaO in glaze is a solvent in glaze, which can reduce the viscosity of glaze melt, improve the fluidity and gloss of glaze, reduce the expansion coefficient of glaze, and improve the mechanical strength of glaze. The increase of CaO content (within the range of mass fraction 0.3%-1%) will increase the melting temperature and viscosity of glaze. If the content is too high, the gloss of glaze will decrease.

[0013] TiO in glaze 2 It increases the opacity, acid resistance and gloss of the glaze. Due to its good opacity, the glaze only needs a thin coating, so this porcelain layer has high thermal stability, impact resistance and flexural strength, good chemical stability, enhanced acid and alkali resistance, and titanium is also one of the main raw materials for the production of barium titanate.

[0014] BaO in the glaze is a flux. Barium has the largest ion radius and the strongest alkalinity among alkali metals. It is also the best fluxing agent among alkali metal oxidations. It can also improve the glaze's resistance to organic acid corrosion. At the same time, barium and titanium undergo a series of complex chemical reactions to generate barium titanate. Barium titanate is a high resistivity substance. Barium titanate in porcelain glaze can increase the overall resistivity of the porcelain glaze, which is beneficial to the powder coating rate of electrostatic powder.

[0015] K in glaze 2 O and Na 2 O is a strong flux for glaze, which can significantly reduce the melting temperature and high-temperature viscosity of the glaze, increase the refractive index of the glaze, and thus improve the glossiness of the glaze surface, which is conducive to obtaining a high-gloss enamel after the glaze of the present invention is fired. 2 O and Na 2 O has a low melting point and is easily reacted with SiO during the glaze melting process. 2 When a chemical reaction occurs, a large amount of heat is released, thereby reducing the external heating temperature and reducing the viscosity at high temperatures.

[0016] CaF in glaze 2 It is a strong solvent that can reduce the high-temperature viscosity of the glaze and also has a significant promoting effect on adhesion. 2 It will also reduce the acid resistance of the glaze, so its content needs to be reasonably controlled.

[0017] CuO, CoO and NiO in the glaze are adhesives. The three adhesives interact with each other. Their interaction can react with iron, allowing the glaze to penetrate into the surface of the steel plate, promoting the glaze to infiltrate the surface of the steel plate at high temperature, promoting the dissolution of iron and iron oxide, controlling the oxidation conditions of the interface, and is conducive to the formation of a more uniform bubble structure in the porcelain layer, forming good adhesion between the base glaze and the steel plate.

[0018] It can be seen from the above technical solution that, compared with the prior art, the beneficial effects achieved by the present invention are:

[0019] The present invention uses titanium dioxide and barium oxide to generate barium titanate through the overall ratio of the above components. Barium titanate has a large resistivity, dielectric constant, and excellent insulation. Barium titanate can well improve the dielectric properties, resistivity and insulation of the glaze, increase the power storage capacity, and thus improve the powder loading rate of static powder. CoO, CuO, NiO, etc. are used in combination with other components to ensure the adhesion, acid resistance, and porcelain surface properties of the glaze. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] Example 1

[0022] A titanium enamel glaze material comprises the following components: SiO 2 , B 2 O 3 , CaO, TiO 2 ,BaO,Na 2 O, K 2 O, CaF 2 , CoO, CuO, NiO, the specific mass fraction of each component is shown in Table 1.

[0023] The glaze obtained in Example 1 was made into an electrostatic dry powder, and the powder's fluidity, 40-min powdering rate, one-time powdering rate and other properties were tested. The test results are shown in Table 2.

[0024] The glaze obtained in Example 1 was made into an electrostatic dry powder, which was sprayed on a 0.75 mm thick zero-carbon steel plate using an electrostatic spray gun. The powder was fired at 860°C for 4 min. The adhesion, porcelain layer thickness, and acid resistance of the sample were tested, and the porcelain surface quality was observed. The test results are detailed in Table 3.

[0025] Example 2

[0026] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results related to this embodiment are detailed in Tables 2 and 3.

[0027] Example 3

[0028] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results related to this embodiment are detailed in Tables 2 and 3.

[0029] Example 4

[0030] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results related to this embodiment are detailed in Tables 2 and 3.

[0031] Example 5

[0032] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results related to this embodiment are detailed in Tables 2 and 3.

[0033] Example 6

[0034] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results related to this embodiment are detailed in Tables 2 and 3.

[0035] Example 7

[0036] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results of various items at different firing temperatures in this embodiment are detailed in Tables 2 and 3.

[0037] Example 8

[0038] The main difference between this embodiment and embodiment 1 is that the mass fractions of the glaze components are different, and the specific differences are detailed in Table 1; the test results of various items at different firing temperatures in this embodiment are detailed in Tables 2 and 3.

[0039] Control group

[0040] The inventors purchased commercially available enamel acid-resistant glaze electrostatic powder and tested the fluidity, 40-min coating rate, one-time coating rate and other properties of the electrostatic powder. The test results are detailed in Table 2.

[0041] Commercially available electrostatic powder was sprayed on a 0.75 mm thick zero-carbon steel plate using an electrostatic spray gun and fired at 860°C for 4 min. The samples were tested for adhesion, porcelain layer thickness, acid resistance, and porcelain surface quality. The test results are detailed in Table 3.

[0042] Table 1 List of mass fractions of each component in Examples 1 to 8 (%)

[0043] Components Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 <![CDATA[SiO 2 ]]> 52.78 55 52.78 52.78 52.78 52.78 52.78 52.78 <![CDATA[B 2 THE 3 ]]> 14.63 13 14.63 13 13.5 13 14.63 14.63 CaO 0.59 0.59 0.59 0.59 0.59 0.59 1 0.59 <![CDATA[TiO 2 ]]> 5.28 5.28 7 5.28 5.28 7 5.28 5.28 BaO 8.2 8.2 8.2 8.2 10 10 8.2 8.2 <![CDATA[Na 2 The]]> 10.53 9.94 8.81 10.29 9.86 9 10.12 10.53 <![CDATA[K 2 The]]> 3.59 3.59 3.59 3.59 3.59 3.23 3.59 3.59 <![CDATA[CaF 2 ]]> 2.13 2.13 2.13 4 2.13 2.13 2.13 2.13 CoO 0.95 0.95 0.95 0.95 0.95 0.95 0.95 0.79 CuO 0.53 0.53 0.53 0.53 0.53 0.53 0.53 0.53 NiO 0.79 0.79 0.79 0.79 0.79 0.79 0.79 0.95

[0044] Table 2 Powder performance test results of Examples 1 to 8 and the control group

[0045] project 40min powder coating rate One-time powdering rate (g) Liquidity Example 1 88.53％ 15.23 202.31 Example 2 85.21％ 14.38 201.55 Example 3 87.35％ 15.21 206.38 Example 4 81.84％ 14.32 201.21 Example 5 85.02％ 14.22 200.54 Example 6 88.27％ 15.32 198.37 Example 7 85.39％ 14.26 200.59 Example 8 88.47％ 15.66 199.68 Control group 70.28％ 13.61 198.11

[0046] Table 3 List of performance index test results of enamel panels of Examples 1 to 8 and the control group

[0047]

[0048]

[0049] Combining Table 1, Table 2 and Table 3, it can be seen that the glazes obtained according to the components and mass fractions of Examples 1 to 8 are made into electrostatic powders, and their 40-minute powder application rates are all above 80%, far ahead of the control group; the one-time powder application rate is slightly higher than that of the control group, and the fluidity is not much different; the performance of the enamel plate made of the electrostatic powder made of the glazes of Examples 1 to 8 is basically the same as that of the control group, and the acid resistance is slightly better than that of the control group. Therefore, the electrostatic dry enamel acid-resistant glaze obtained by the present invention has a good powder application rate while ensuring good acid resistance, adhesion, porcelain surface and other performance bases.

[0050] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An electrostatic dry enamel acid-resistant glaze, characterized in that: Includes the following components: SiO2, B2O3, CaO, TiO2, BaO, Na2O, K2O, CaF2, CoO, CuO, NiO.

2. The electrostatic dry enamel acid-resistant glaze according to claim 1, characterized in that: The mass fraction of each component is as follows: SiO250-60%; B2O313-19%; CaO 0.30-1.0%; TiO24-8%; BaO 5-10%; Na2O 8-15%; K2O3-5%; CaF21-5%; CoO 0.5-1%; CuO 0.1-0.8%; NiO 0.1-1%.

3. The electrostatic dry enamel acid-resistant glaze according to claim 2, characterized in that: The mass fraction of each component is as follows: SiO250-55%; B2O313-15%; CaO 0.50-1.0%; TiO25-7%; BaO 8-10%; Na2O 8-11%; K2O3-4%; CaF22-4%; CoO 0.7-1%; CuO 0.5-0.6%; NiO 0.7-1%.

4. The electrostatic dry enamel acid-resistant glaze according to claim 2, characterized in that: The mass fractions of the components are as follows: SiO2 52.78%; B2O3 14.63%; CaO 0.59%; TiO25.28%; BaO 8.20%; Na2O 10.53%; K2O3.59%; CaF22.13%; CoO 0.95%; CuO 0.53%; NiO 0.79%.

Images