DE1952529A1 - Surface-treated glass block - Google Patents

Description

VE 132

Applicant: Compagnie de Saint-Gobain, 62 Bd. Victor Hugo 92 Neuilly-sur-Seine (France)

Surface-coated glass block

The invention relates to a glass block with improved heat protection properties. It is her task in particular basically to create a glass block with a coating that reflects heat rays. For such glass blocks there is Everywhere there is a need where excessive heating of a room through a glass block wall or through an opening lined with glass blocks penetrating the room Solar radiation should be avoided.

A certain degree of thermal protection can be achieved by using commercially available colored glass blocks. A wide variety of methods are known for coloring glass blocks. With such colored glass blocks, a more or less large part of the incident radiation is usually absorbed by the glass block, thereby reducing the total radiation permeability. However, due to the radiation absorption, the stones heat up and give off part of the absorbed radiation energy in the form of secondary radiation back to the ¹⁷ ^ um. In their effectiveness in terms of thermal protection

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the "known glass blocks are therefore limited. By the Creation of a coating that reflects a significant part of the thermal radiation and therefore excessive heating of the. Avoiding stones itself is supposed to improve the heat protection effect to be reached »

Reflective layers are most effective when placed on top of the Outside, on which the solar radiation falls, applied are. Layers applied to the outside of glass blocks However, and this is an additional requirement, they must be corrosion-resistant otherwise they become unsightly over time and their reflective properties also decrease.

The objects mentioned are achieved according to the invention in that at least one of the visible surfaces of the glass block on the The outside has a layer of one or more heavy metal oxides with a maximum thickness of 300 millimicrons (nanometers), which under pyrolytic decomposition and oxidation of in the form a solution applied heavy metal salts into the glass surface is burned in.

The state of the art includes a number of proposals that deal with the application of transparent color coatings or with the surface treatment of glass blocks. For example, GM 1 742 185 has made a glass block known in which the. Surface in a thin layer from the outside by burning in diffused, coloring heavy metal ions, in particular silver and copper ions. In this technique, also known as "pickling of glass", the metal ions penetrate the surface of the glass to a depth of about 20 μ.

Attempts have also been made to use luster colors and transparent

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Burning emails on the outside of glass blocks. However, these layers neither have the desired reflective properties, nor have they proven to be corrosion-resistant. There are also glass blocks known in which to achieve a decorative character coatings made of transparent Enamel are applied to the inside of the hollow glass block (GH 1 957 03 * 0, as well as those where a transparent The color coating is baked on the outside and the color coating is provided with a top layer of colorless varnish is (GM 1 777 0? -3).

Compared to all these prior art glass blocks also provided with burnt-in layers, the new glass block has the advantage of excellent corrosion resistance and a remarkable thermal protection effect by reflecting a considerable proportion of the incident thermal radiation. For example, while the known glass building blocks reflect an order of magnitude of ΛΟϊί of the incident radiation, the new glass building blocks achieve reflection values of up to 40 / S-, whereby the permeability in the visible light range is 35 to 55%, depending on the design.

Can raise the effect of heat radiation reflection by choosing and through the composition of the heavy metal oxides, a whole range of color shades can be achieved. During e.g. tin oxide layers are colorless when viewed through, coatings made of iron oxide are bronze-colored, and coatings made of nickel-plated and cobalt oxide are essentially neutral gray.

In the invention, the Schwermetalloxidschicht is thereby firmly anchored to the glass surface in that it is manufactured by spraying a heavy metal salt solution to the heated to a temperature of 500 to 600 ⁰ C glass block.

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To determine the maximum thickness that the oxide layer can reach the refractive index of the respective oxide layer must also be taken into account. To avoid iridescence, the "optical layer thickness", i.e. the geometric layer thickness multiplied by the refractive index, may have a value of Do not exceed 400 millimicrons.

It is also expedient to increase the corrosion resistance of the heavy metal oxide layer if the heavy metal oxide layer has a content of at least 10% by weight of chromium oxide.

Particularly suitable heavy metal oxides are the oxides of the following metals: iron, nickel, cobalt, chromium, manganese, copper, Lead, tin, vanadium, zircon, bismuth, antimony, lanthanum, indium and cerium.

In contrast to the well-known colored glass blocks that-in Usually for the optical loosening of walls consisting essentially of colorless glass blocks as individual stones or inserted into the walls as groups of stones, the new stones are preferably put together to form whole walls, whereby the desired heat protection effect is optimally achieved.

According to a preferred method, which has the particular advantage that no additional heat treatment is necessary to burn in the oxide layer, the heavy metal oxide layer is produced in that in the course of the production of the glass blocks after the two half-stones have been welded together at a time when the temperature the stones about 500 - is 600 ⁰ C, a metal salt solution nit the desired metals on the glass blocks by means of a spray gun spraying. Next to

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the use of the stone's own heat to burn in the Metal oxide layer it has been found that "in this process there is also optimal adhesion and corrosion resistance of the metal oxide layer. For further illustration two exemplary embodiments for the production of the new glass blocks are shown.

Example 1:

To produce a neutral gray coating, 16.24 g Cobalt octoate in 38 g xylene, also 3 * 2 g nickel acetylacetonate and 4.0 g chromium acetylacetonate dissolved in 73> 4 g benzene, and this both solutions mixed together. From this mixture, depending on the type of spray gun and with the help of a spray gun

depending on local conditions 50 to 300 g per m of glass surface immediately after the welding process, in which the two stone halves are welded together, ie at a temperature of the glass ^{block of about 600 0} C, sprayed evenly on both visible surfaces of the glass blocks. After the glass blocks have cooled down, they have a coating consisting of 70% Co ₅ O ^, 15.6% NiO and 14.4% Cr ₂ O *. The visible thickness is an average of 5 to 10 millimicrons. The glass blocks have a total radiation transmission of 56%, a total radiation reflection of 19% and accordingly an absorption of 25% · In the range of visible light the radiation transmission is 53%.

Example 2:

10.5 g of chromium acetylacetonate and 11.8 g of iron acetylacetonate are dissolved in 78 g of benzene. From this solution 50 to 300 g

per m glass surface as described in Example 1, sprayed onto the glass blocks. After the glass blocks have cooled, they in turn have an iron-chromium-oxide coating with an average of 5 to 10 millimicrons thick with 54% -ΡβρΟ ^ ^and

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CrpO, which has a light bronze tone when viewed through. The total radiation transmission is 4-3%, the reflection 31 % and the absorption 26%. In the visible light range, the transmittance is 36%.

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Claims (5)

VE 132 Claims (λ.) Surface-treated glass block, characterized in that at least one of its visible surfaces has a layer of one or more heavy metal oxides on the outside of a maximum of 500 millimicrons thick, which is burned into the glass surface with pyrolytic decomposition and oxidation of heavy metal salts applied in the form of a solution is. 2. Glass block according to claim 1, characterized in that the heavy metal oxide layer has an "optical layer thickness", d. H. the product of the geometric layer thickness and the refraction index the layer, not exceeding AOO millimicrons. 3- glass block according to claim 1 and 2, characterized in that that the heavy metal oxide layer is chromium oxide, preferably in a proportionate amount of more than 10% by weight. 4. Glass block according to claim 1 to 3, characterized in that that the heavy metal oxide layer contains the oxides of the metals iron, Nickel, cobalt, chromium, manganese, copper, lead, tin, vandium, zircon, vismuth, antimony, lanthanum, indium and cerium alone or in connection with each other. 5. A method for producing a glass block according to a or more of claims 1 to 4-, characterized in that that a solution of heavy metal salts on the hot, a Temperature of about 500 - 600 ° C having glass block is sprayed on. 0098 50/1311 Lee rs e it e