METHOD OF MAKING AN ENAMELED SANITARY FIXTURE

Abstract

A method for making an enameled sanitary product has a first step of applying a coating compound formed from at least one ground-enamel frit to a metallic base body. The compound contains a thermally unstable additive that decomposes when heated. Then the base body coated with the compound is fired such that the additive thermally decomposes and produces gas inclusions and craters that produce bubbles in and craters on the fired coating compound that are fixed by cooling.

Claims

1. A method for making an enameled sanitary product, the method comprising the step of: applying a coating compound formed from at least one ground-enamel frit to a metallic base body, the compound containing a thermally unstable additive that decomposes and generates gas when heated; firing the base body coated with the compound such that the additive thermally decomposes and generates gas inclusions that form bubbles in and craters in the fired coating compound; and curing the fired base body and coating such that the bubbles and craters are fixed in the coating.

2. The method defined in claim 1, wherein the additive includes at least one magnesium carbonate compound.

3. The method defined in claim 1, wherein, based on 100 parts by weight of ground-enamel frit, the coating compound contains between 0.4 and 5 parts by weight of the thermally unstable additive.

4. The method defined in claim 1, further comprising the step of: grinding the enamel frit and additive together prior to application of the coating compound to the base body.

5. The method defined in claim 4, wherein, during the grinding process, at first only the enamel frit is ground, and then the thermally unstable additive is added.

6. The method defined in claim 1, wherein, based on 100 parts by weight of enamel frit, at least 20 parts by weight of matte frit are provided.

7. The method defined in claim 6, wherein, based on 100 parts by weight of enamel frit, between 40 and 60 parts by weight of matte frit and between 60 and 40 parts by weight of glossy frit are used.

8. The method defined in claim 1, wherein, based on 100 parts by weight of enamel frit, at least 10 parts by weight of ground quartz are used.

9. The method defined in claim 8, wherein, based on 100 parts by weight of enamel frit, between 10 and 40 parts by weight of ground quartz and between 90 and 60 parts by weight glossy frit are used.

10. The method defined in claim 1, wherein the firing step is carried out at a maximum temperature between 750 C. and 900 C.

11. The method defined in claim 1, wherein the base body is a deep-drawn steel sheet.

12. A blank for forming an enameled sanitary product, the blank comprising the metallic base body and coating made according to the method of claim 1.

13. An enameled sanitary product comprising: a metallic base body; and a top enamel coating on the base body made of a ground-enamel frit mixed with a thermally unstable additive that generates gas when heated to form gas bubbles and craters in the coating.

14. The enameled sanitary product defined in claim 13, wherein the top enamel layer directly engages the metallic base body.

15. The enameled sanitary product defined in claim 13, for use as a tread or floor covering, the coating having a surface falling under evaluation group B or C according to DIN 51097:1992.

Description

BRIEF DESCRIPTION OF THE DRAWING

[0043] The above and other objects, features, and advantages will become more readily apparent from the following description, reference being made to the accompanying drawing in which:

[0044] FIG. 1 is a section through an enameled sanitary product according to the invention;

[0045] FIG. 2 is a view like FIG. 1 of an alternative embodiment of the enameled sanitary product; and

[0046] FIG. 3 a top view of a sanitary product according to FIG. 1 or FIG. 2.

SPECIFIC DESCRIPTION OF THE INVENTION

[0047] The enameled sanitary product can be preferably a bathtub, shower base, shower surface, or a floor panel, in which case a tread is formed for a user on the top side. According to FIG. 1 it has a metallic main body 1 usually made of a steel sheet. A single top enamel layer 2 is formed on the base body 1 as a direct enamel that is formed according to Table 1 from the mixture of various ground frits.

[0048] According to the invention, a thermally unstable additive, particularly a magnesium carbonate compound, is added during the preparation of the coating compound, which is usually applied as a slurry, with the thermally unstable additive decomposing at least partially during the firing process to form gas.

[0049] In this connection, FIG. 1 shows the structure of the top enamel layer 2 that is ultimately frozen in place in the finished enameled sanitary product. During the firing process, the decomposition of the magnesium carbonate compound forms gaseous carbon dioxide on the one hand and magnesium oxide on the other, and they are is incorporated into the glass structure of the top enamel layer 2. In addition, water vapor can also be generated.

[0050] Due to the viscosity of the top enamel layer 2 during the baking process, the gas generated is limited in its mobility. Inclusions 3 first occur in the form of carbon dioxide bubbles. When such a carbon dioxide bubble reaches the surface, it bursts or emerges from the enamel layer 2. A crater-shaped formation 4 is then produced with a depression 5 and a raised wall 6.

[0051] Since only a portion of the carbon dioxide bubbles can emerge from the top enamel layer 2, the enameled sanitary product according to FIG. 1 has both inclusions 3 and crater-shaped formations 4 that together increase the waviness or roughness of the surface formed by the top enamel layer 2 and thus contribute to improved slip resistance.

[0052] In order to enable only one top enamel layer 2 to be applied directly to the metallic base body 1 as a direct enamel, the base body 1 is usually nickel-plated and/or made of a nickel steel in order to make sufficient adhesion of the directly applied top enamel layer 2 possible.

[0053] Given this, a two-layered construction is frequently provided, especially for sanitary products, with FIG. 2 showing a base enamel layer 7 between the metallic base body 1 and the top enamel layer 2. The base enamel layer 7 and the top enamel layer 2 are baked in two successive firing processes. In the context of such an embodiment as well, the advantage exists over the prior art that the desired slip resistance can be achieved directly with the production of the top enamel layer 2.

[0054] In a highly magnified plan view, FIG. 3 shows a cut-out from the surface of an enameled sanitary product according to the invention with an edge length of 2.4 mm by 2 mm. The size of the individual crater-like formations 4, the size distribution, and the spatial arrangement can be estimated on the basis of the exemplary cut-out for a specific embodiment.

[0055] In the context of the invention, the inclusions 3 and thus also the crater-shaped formations 4 typically have a diameter of between 30 m and 350 m. A mean diameter is typically between 60 m and 200 m, for example about 120 m