Enamel Paint’s Origin

At a time when paints were less than reliable and whitewash paints were friable and known to smudge off, calling a product “enamel paint” was a powerful marketing move in the mid-1800s.

Enamel was associated in consumers’ minds with the vitreous shell surfaces of porcelain and ceramic tiles, or of porcelain bathroom fixtures, all of which were impermeable, sanitary, and very tough. Translating the idea of cookware, tile, sinks, and bathtub enamel to paint was a convenient shortcut to indicate that this paint was equally water-resistant and tough.

Powder coating has largely replaced baked enamel coating for industrial applications. However, enamel paint’s main competition came when synthetic latex paints were introduced after World War II. Today, enamel paint still has some associations with hard-shelled items such as large appliances like refrigerators and washing machines, though these too are now powder-coated.

FROM:thespruce

Hunan Noli Enamel Co., Ltd has been focusing on Porcelain Enamel Coating for over 30 years.

As the leader manufacturer of Porcelain Enamel in China, Our Annual Capacity:

                               Ready To Mill (RTM) Porcelain Enamel Material

                               Porcelain enamel Powder ( electro static powder)

Black RTU Enamel Powder

Black RTU Enamel Powder A-10-3

A-10-3 is pre-grinding black enamel powder which fineness is 30 mesh. There would be 25-30g residue when 100g powder is passed through 140 mesh standard sieve.

The coating made of such product has smooth surface, fine adherence, good stability and appropriate glossy could be obtained when firing temperature & time is controlled well.

MATERIALS RATIO:
RTU Powder 100
Water 36-40ml
APPROVABLE STANDARD:
a. Appearance: black powder. The coating is the same as standard which is smooth and without bubble mark.b. Firing temperature: 830–850℃

c. Adherence: Grade 1 -2

d. Glossy: standard ≤±5

e. Fineness: 30 mesh; There would be 25-30g residue when 100g powder is passed through 140 mesh standard sieve.

TEST METHOD:
1) Mill the powder with water by ball mill for 6~8 minutes until the fineness becomes 0.5-1g/100ml.150 mesh.

2)Pass it through 80 mesh sieve and make the consistency to be 165~170g/100ml,(1.65~1.7g/cm3). Compare it with standard samples.

3) Cover 100-140 micron such enamel on a sheet steel (thickness 0.8~1.0mmⅹwidth 100mmⅹlength 100mm) and fire them at 830-850℃ for 2~3 minutes.

NOTE:
The thickness of glaze slip, fineness of powder, firing temperature & time should be adjusted and controlled very well to get a good coating gloss.

enamel413

What Is Enamel Paint?

Enamel paint is defined more by its qualities than by its content. In the broadest sense, enamel paint means any solvent-based paint that dries to a hard, vitreous (glass-like) shell. Solvent-based paints are also called oil-based paints, in contrast with water-based paints.

Enamel paint springboards off of its root words “smelt” or “melt,” since true enamel is a glass coating that is melted or kiln-baked at extremely high temperatures onto metal or ceramics. Note, however, that enamel paint bears no similarities with the enamel of molten glass, as there is no glass content in this kind of paint. Even traditional baked enamel finishes, long used for vehicles, have nothing to do with glass. The baking is simply a fast route to eliminating solvents and VOCs.

In reality, air-dry enamel paints are far softer than true enamels formed in a kiln. Paint manufacturers have further widened the definition by sometimes attaching the word enamel to water-based paints, thus losing the one ingredient that usually ties together all enamel paints: solvents.
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FROM:thespruce.com

Basic knowledge of enamel glaze

It is used for coating and glazing on metal green tires. It is composed of alkali-boron-silicate glass-like substances. Enamel glaze is coated on metal green bodies. After firing, they can be firmly combined with the green bodies. Decorative effect
The basic ingredients of the enamel glaze include the following 5 base agents: 40% to 60% of the total enamel glaze. The ingredients that determine the main properties of the enamel glaze include silicon oxide, zirconia, titanium oxide, and other fluxes: promote the melting of the enamel glaze and improve its process. Properties and physical and chemical properties: Emulsifiers such as sodium oxide, potassium oxide, boron oxide, etc .: Provide good covering ability to the body. Adhesives such as titanium oxide, antimony oxide, zirconia, strontium oxide, etc .: The ceramic glaze and the body are firmly combined with cobalt oxide and nickel oxide. Copper oxide, antimony oxide, molybdenum oxide, and other colorants: Various colors are given to the enamel glaze to achieve decorative effects. The components are cobalt oxide in bright blue; copper oxide in green or red; chromium oxide in dark green; iron oxide in ochre red, etc. The amount of such oxides is generally 0.1 to 2.5%

It is used for coating and glazing on metal green tires. It is composed of alkali-boron-silicate glass-like substances. Enamel glaze is coated on metal green bodies. After firing, they can be firmly combined with the green bodies. Decorative effect
The basic ingredients of the enamel glaze include the following 5 base agents: 40% to 60% of the total enamel glaze. The ingredients that determine the main properties of the enamel glaze include silicon oxide, zirconia, titanium oxide, and other fluxes: promote the melting of the enamel glaze and improve its process. Properties and physical and chemical properties: Emulsifiers such as sodium oxide, potassium oxide, boron oxide, etc .: Provide good covering ability to the body. Adhesives such as titanium oxide, antimony oxide, zirconia, strontium oxide, etc .: The ceramic glaze and the body are firmly combined with cobalt oxide and nickel oxide. Copper oxide, antimony oxide, molybdenum oxide, and other colorants: Various colors are given to the enamel glaze to achieve decorative effects. The components are cobalt oxide in bright blue; copper oxide in green or red; chromium oxide in dark green; iron oxide in ochre red, etc. The amount of such oxides is generally 0.1 to 2.5%

Melted fully-mixed batches are melted and quenched into a stable enamel glaze at a high temperature (1250 ~ 1400) through a series of physical and chemical reactions. Some of the melts must be fully melted after being melted, and some of them will be semi-melted after being quenched There are three crucible furnaces: crucible furnace furnaces and rotary furnaces, which are also called round furnaces. The batch materials are melted in the crucible and melted at high temperature to complete the melting process. Multiple crucibles are placed to melt different enamels, but the output is small. The thermal efficiency is low. The pool furnace uses continuous operation to feed the materials directly into the furnace for high temperature melting. ) The furnace furnace has a large output, high thermal efficiency, high energy and stable operation, but can only melt a single variety of enamel glaze rotary furnace materials at the same time. The molten horizontal fuel furnace is injected from the end of the cylinder furnace and turned over. The batch is made to melt and operate intermittently. This method has a large output and low heat consumption. The melting quality is more uniform.

Grinding the enamel glaze block into glaze slurry or glaze powder glaze slurry for dipping, coating, electrophoresis, or electrostatic spray glaze powder for spraying, spraying, or electrostatic spraying. Commonly used grinding equipment is the inner lining of a batch ball mill. And ball stones are usually made of quartz hard ceramic or corundum

The types are usually divided into bottom glaze and side glaze. According to the material of the body, it is divided into steel enamel glaze, cast iron enamel glaze, aluminum enamel glaze, copper enamel glaze, and gold and silver enamel glaze. Among them, steel enamel glaze and cast iron enamel glaze application are divided according to the characteristics of enamel glaze. According to the characteristics of enamel glaze, titanium glaze, antimony glaze, etc. are divided into acid-resistant glazes, alkali-resistant glazes with good mechanical properties, wear-resistant glazes, microcrystalline glazes with good mechanical properties, and luminous glazes with optical characteristics, high-temperature glazes with thermal characteristics, etc.

The main effect of the enamel glaze which is directly coated on the green body is to make the green body and the top glaze have a strong bond (adherence). The base glaze can be divided into nickel base glaze, cobalt base glaze, cobalt nickel base glaze, antimony molybdenum base. Cobalt and nickel base glazes such as glazes and mixed base glazes have the widest application range. Antimony molybdenum base glazes are milky white, also known as white base glazes. They have the lowest cost. They are commonly used as base glazes for daily enamels. Mixed base glazes are made by mixing several base glazes in proportion. Improve the firing process performance and improve the adhesion effect of enamel with the green body. It is often used as a base glaze for thick-walled large enamel products with a long firing time.

Glazed glaze Glazed glaze coated on the surface of the product can be divided into milky glaze, colored glaze, transparent glaze, etc .; according to its characteristics, it can be divided into acid-resistant glaze, alkali-resistant glaze, wear-resistant glaze, microcrystalline glaze, luminous glaze, high-temperature glaze, and insulating glaze.

Milky white glaze: Milky white which gives the top glaze strong hiding power. According to the type of opacifying agent in the glaze, it is mainly divided into titanium white glaze, antimony white glaze, and the titanium dioxide in the former porcelain glaze is recrystallized during firing to give the porcelain glaze super milky properties. The thinner layer is the most widely used surface glaze for daily enamels; the latter has an opacifying effect that is inferior to that of titanium dioxide, so the antimony surface porcelain layer is often used in cast iron bath glazes or other non-food enamel products.

Colored glaze: Add coloring agent to milky white glaze. The coloring agent can be added by melting or ball milling. Color glazes mainly include titanium color glaze and antimony color glaze.

Transparent glaze: porcelain glaze with no opacifying effect and transparent appearance is often coated with a layer of transparent glaze to enhance gloss. It is also often used as a base glaze for grinding and coloring. The transparent glazes commonly used for decorative flower glazes are mainly Titanium dioxide transparent glaze

Chemical characteristics Glaze: There are acid-resistant and alkali-resistant glazes. The content of silica in the acid-resistant glaze composition is greater than 65%. It is mainly used for coating chemical machinery enamel products. Alkali-resistant glaze composition is often introduced with a large amount of zirconium dioxide. Chrome oxide titanium dioxide can also be introduced to improve the resistance. Alkali properties

Mechanical properties glaze: wear-resistant glaze can be used to increase the wear resistance of the glaze in two ways. One is to add abrasive components such as silicon carbide boron nitride to the porcelain glaze; the other is to micro-crystallize the porcelain glaze to obtain good wear resistance. Microcrystalline enamel

Optical characteristics glaze: The luminous glaze is added to the enamel glaze by introducing luminous substances such as zinc sulfide and cadmium sulfide.

Thermal characteristics glaze: high-temperature glaze can be used in the temperature above 750 temperature enamel glaze resistance to rapid temperature change performance good enamel composition does not allow alkali metal oxides often contain a large amount (up to 40%) boron oxide and a small amount of beryllium oxide still need to be ground Adding a certain amount of refractory substance such as alumina, chromium oxide and other high-temperature glazes are often used for the protection of jet components or for high-temperature coating of atomic energy reactors.

Electrical characteristics glaze: The resistance glaze is an insulating enamel glaze with a large resistivity. Its composition does not allow alkali metal oxides. It is often used as an insulating material for wires or as an insulating coating material for printed circuit boards.

The enamel enamel enamel enamel enamel products have a coefficient of thermal expansion larger than that of the general face glaze, which has a wider firing range and better elasticity. The edge enamel has a variety of colors and is often used for edge decoration.