The range of produced ceramic tiles for flooring and wall cladding is very large. Tiles can be:
enameled (glazed) or not enameled
Enameled tiles have a surface covered with a layer of colored glass, which gives them important aesthetic characteristics (color, shine, decorative pattern, various shades, etc.), as well as technical properties (hardness, impermeability, etc.). All these characteristics, both technical and aesthetic, depend on the type of enamel and can vary within a very wide range. Unenamelled tiles are practically uniform throughout their thickness and usually do not have any decorative patterns.
with a porous or dense base
The base is the tile body itself. The body can be dense (almost like glass) or porous. Naturally, we can talk here about pores visible only under a microscope. Of course, no one counts the number of pores under a microscope, and for their quantitative measurement, water is used, which is absorbed by the pores. In other words, porosity is determined by the amount of water absorbed by the pores. And the more water is absorbed, the more porous the tile body is considered.
pressed or extruded
Pressing or extrusion are two molding methods used in the production of ceramic tiles. Pressed ceramic tiles are made from a powder mixture that is compacted and formed under high pressure in a press. Extruded tiles are made from a doughy mass of raw materials and are molded by passing through a special hole - an extruder.
from a red, white or colorless mass
Depending on the raw material, the body of the tiles can be colored (from yellow to dark red with many intermediate tones) or colorless (sometimes white). The color of the case in the enamel tiles is of no practical importance. In some non-enamelled products, different colors are achieved by the addition of coloring pigments.
of various shapes and sizes, i.e. different "format"
The most common shapes are square and rectangle, but there are also other, sometimes very complex shapes (for example, hexahedron, octahedron, Provencal shape, Moorish shape, etc.). As for the sizes, the size of the tiles can be from "mosaic" (tiles with a surface area of less than 90 cm2) to real slabs with a side of 60 cm or more. The thickness varies from a few millimeters to 2-2.5 cm.
Ceramic tiles are classified according to types with special technical and commercial names. These types differ from each other, on the one hand, in the above-mentioned characteristics, on the other hand, in their manufacturing technology.
The main types of tiles:
Majolica (extra durable ceramic tiles)
Enamel tiles with a porous color base, molded by pressing. Manufacturing technology provides for two separate firing: the first - for the body of the tile, the second - for the enamel (double firing allows you to avoid cracks and "midges" on the surface). The result is a smooth, shiny and highly decorative tile.
The raw material for the production of majolica is a mixture of clay, sand, carbonate and iron oxide (gives the base of the tiles a pinkish tint). Only opaque colored glaze is used.
Sizes: the most common are 15x15, 15x20, 20x20 cm.In combination with large elements, small items are used - 10x10 cm.
It is used for cladding interior walls of residential premises with low air humidity (not intended for bathrooms, showers and similar premises, since majolica is a highly porous material and has a high water absorption - 15-25%).
Faience - white mass
Enamel tiles with a porous white base, molded by pressing. Double fired. Faience tiles are pressed from light, iron-free clays, so only the glazed surface is colored. The quality of earthenware tiles depends on the stability (homogeneity) of the raw materials (selection and careful preparation is required).
Firing is carried out according to a special stepped mode - with holdings at a certain temperature. This is an important point because if, for example, too quickly to pass the mark of 600 ° C, complete burnout of organic impurities present in the clay may not occur. This may result in a defect called (black core). Incorrectly fired specimens quickly lose color, have an irregular shape and are easily destroyed.
It is used for flooring and wall cladding of building interior.
Sizes are 20x20, 15x20, 30x30 cm and others.
Monocottura (single fired tiles)
Enamel tiles with colored (red) or light (from light gray to beige) compacted or porous base, molded by pressing. Coloring depends on the content of iron in the clay. The technology provides for only one firing procedure, to which both the base and the enamel are subjected simultaneously. The main advantage of this approach is the low price of the product.
Tiles can have both high and very low porosity. Low-porosity has good frost resistance (since it absorbs less water) and is more expensive.
Special types of such tiles are "pressed-enamel" - tiles obtained by applying powder enamel at the time of pressing, and tiles with "enamel on a hot body" - tiles obtained by applying special granular enamels to a red-hot body.
It can be in sizes 10x20, 20x20, 30x30, 40x40, 60x60 cm.
It is used for laying floors and wall cladding both inside and outside the building.
Unenamelled or single-fired enamelled tiles with a multi-colored (usually compacted) base, obtained by extrusion. The raw mix is fired at temperatures up to 1250 ° C up to the beginning of glazing. The use of the extrusion process makes it possible to obtain not only tiles of complex geometric shapes, but also various facing elements - plinths, corners, steps, etc. The tile has good characteristics of resistance to mechanical stress, abrasion, weathering and temperature changes. Resistant to aggressive chemicals, easy to clean, unpretentious in operation.
Sizes: produced in a wide variety of sizes and shapes, the most typical are 12x22, 20x20, 30x30 cm and others.
It is used for laying floors inside and outside the building, facing the outer walls of residential, public, industrial, sports facilities.
Unamelled tiles with a red porous backing obtained by extrusion.
It is a ceramic material made from various types of clays. Extruded and dried tiles are fired at temperatures up to 1110 ° C. The base is porous, red in color with a variety of shades (depending on the type of clay).
Possesses increased resistance to the effects of abrasive materials, is characterized by high resistance to compression, bending, the action of aggressive chemicals and atmospheric phenomena.
The shape is square, rectangular, hexagonal and octagonal. The most common are large tile sizes - 25x25, 30x30, 20x40, 40x60 cm (with the exception of 10x10 cm tiles).
It is used for flooring inside buildings. Fired tiles can also be used for facade cladding.
Colored glass tiles. Made from molten glass melt. In the manufacturing process, tiles are first cast (sometimes pressed) and then fired. The color palette of smalta includes hundreds of different colors and shades, which makes it possible to obtain highly artistic panels with its help. Differs in resistance to any aggressive environment, as well as color fastness. The water absorption coefficient is practically zero, which determines its scope.
It is used for finishing the underwater part of pools, as well as for mosaic work.
Tiles made of special heavy clays with added minerals. Molding takes place under a pressure of about 500 kg / cm2. Then the tiles are fired in an oven at a temperature of about 1250 ° C. To give the material the desired color, special mineral pigments are added to the raw material. As a result, the tile has a very dense and even structure, which ensures its high hardness (on the MOHS scale - 8 units, for comparison, the hardest material diamond has 10 units), mechanical strength and low water absorption (0.02-0.05 percent), which makes it resistant to frost, as well as to sudden changes in temperature. The tile is evenly colored throughout its entire thickness, so it practically does not fade over time. The tiles are made with a relief, matte, polished surface and even glaze.
They are made in sizes 15x15, 20x20, 30x30 cm and other sizes, with a thickness of 7.5 to 12 mm.
It is used for devices of surfaces exposed to high mechanical stress and requiring increased resistance to chemicals and frost.
Ceramic granite is such an interesting material that it deserves a separate discussion about itself. And we will definitely return to this topic.
There are other varieties on the market that differ from those listed by us. For example, cotto - enameled or clinker obtained by pressing.