The difference between porcelain glazed tiles and glazed tiles


Release time:

2023-05-12

With more and more domestic ceramic enterprises investing in the research and development of inkjet and infiltration technology, the inkjet and infiltration process is gradually improving, and ceramic tiles have come into our sight.

The difference between porcelain glazed tiles and glazed tiles

With more and more domestic ceramic enterprises investing in the research and development of inkjet and infiltration technology, the inkjet and infiltration process is gradually improving, and ceramic tiles have come into our sight. As one of the core technologies of ceramic tiles, inkjet infiltration refers to the process of using ion diffusion, surface adsorption, and other functions to make inorganic chemical raw materials undergo appropriate treatment under certain process conditions to overcome surface tension and penetrate downwards into the tiles to a certain depth. So what is the difference between porcelain glazed tiles and the commonly used glazed tiles?
From the perspective of process flow
There are two processes for ceramic tiles:
(1) Dry method: secondary fabric (thin material on the brick) - pressing - drying - surface decoration (inkjet infiltration, effect glaze, etc.) - firing - polishing - anti fouling treatment
(2) Wet method: fabric - pressing - drying - drenching - drying - surface decoration (inkjet, effect glaze, etc.) - firing - polishing - anti fouling treatment
Process flow of glazed tiles:
Fabric - Pressing - Drying - Applying Surface (Bottom) Glaze - Surface Decoration (Ink Jet, Screen, Roller) - Applying Transparent Glaze (Effect Glaze) - Burning - Polishing - Anti fouling Treatment
From the perspective of ceramic tile structure
Body+surface (bottom) glaze+ink, color glaze+transparent glaze (effect glaze)
So in the polishing stage, ceramic tiles are polished with the fired ceramic layer, while glazed tiles are polished with transparent glaze.
So what is the difference between a porcelain layer and a glaze layer?
From the perspective of raw material structure
The porcelain layer is a fine powder material after surface decoration (penetrating ink, penetrating agent).
The porcelain layer uses refined powder that is more refined than ordinary powder. Permeable ink is a natural color generating element such as cobalt, nickel, titanium, copper, iron, etc. that is directly ionized and chemically combined with organic solvents (color generating agents) to form a colored solution, which is then oxidized and colored during the firing process. Among them, porous nano SiO2 is used as the colorant. The penetration aid plays a role in overcoming surface tension and helping ink penetrate downwards into the fine powder layer.
The glaze layer is transparent glaze.
Glaze mainly consists of feldspar type fluxes, frits, and fluxes. The flux can promote high-temperature differentiation reaction and regulate the physicochemical properties of the glaze layer.
From a microstructural perspective
Porcelain layer:
The surface of the porcelain tiles after inkjet infiltration is a three-dimensional infiltration layer of porcelain. After sintering, the ceramic layer is dense, and the microstructure shows mullite, glass phase, quartz, and pores. The clay and glass phases in the ceramic layer both form mullite, which has higher mechanical strength compared to the glass phase, especially the strength of the network like mullite. Mullite forms the framework of the glass phase in the ceramic layer, significantly altering the strength of the ceramic layer.
Glaze layer:
The surface of glazed tile products is flat printed (or inkjet printed) followed by a transparent glaze layer. The microstructure of the fired glaze layer consists of a large amount of glass phase, a small amount of residual and precipitated crystals, and bubbles. Oxides (such as SiO2) combine with each other in a tetrahedral form in the glaze layer to form an irregular network structure.
Both have high mechanical strength and anti fouling performance, but there are differences in wear resistance and chemical corrosion resistance:
(1) Color
From the perspective of color types, inkjet infiltration flowers are currently not rich and complete in color, and glazed tile products have more color types than inkjet infiltration flowers, and the texture will be more delicate.
However, from the perspective of the visual effect of patterns and colors, the ink-jet infiltration process produces colors inside the porcelain layer, which makes the patterns and colors more three-dimensional. However, due to the diffusion of ink into the fine material layer, there are certain changes in the details after polishing. So there is still a certain gap in the expressive power of details compared to the stacked ultrafine powder ink.
So, both have advantages.
(2) Wear resistance
The surface of glazed tile products is a glass transparent glaze with low hardness (below 5 Mohs) and low wear resistance. The surface of porcelain tiles is a dense porcelain layer with good wear resistance, and the Mohs scale hardness reaches 5.5~6. Can be applied to all occasions, including commercial venues.
Wear resistance: porcelain glazed tiles>glazed tiles
(3) Glossiness
The principle of transparent glaze is that a portion of the light is reflected back to the eye after it touches the body through the glaze layer, which belongs to the mirror reflection of light, usually>99.99%. Porcelain tiles diffuse light back to the eyes when it touches the ceramic layer, ensuring a beautiful viewing experience without irritating the eyes. When the instrument measures the same glossiness, the human sensory ceramic tiles are better than glazed tiles.
(4) Chemical corrosion resistance
When the glaze layer comes into contact with water, acid, or alkali, it will undergo ion exchange, dissolution, or adsorption reactions with these media to varying degrees, and its erosion mechanism is similar to that of glass. Between ions on the network node and ions in the solution, cations are extracted from the glaze, destroying their silicon oxygen bonds, etc. Therefore, the chemical corrosion resistance of transparent glaze glass is slightly poor. And the fine powder forms a dense ceramic layer after high-temperature sintering, with good chemical corrosion resistance.
Chemical corrosion resistance: porcelain glazed tiles>glazed tiles
From the current actual production perspective, the production technology of glazed tiles is already very mature, while porcelain glazed tiles are in the initial stage, and there are still many technical difficulties to be solved. For example, the depth and quality of ink penetration into the body still need to be improved, and the detailed expression of ink penetration on small lines or color overlays is not enough. This may lead to problems such as whitening the patterns and textures or blurring the colors. In addition, the uniform drying of the slurry layer, the color rendering ability of the formula, and the low service life of the inkjet equipment are also technical challenges that cannot be ignored.