Method for manufacturing coloured glass-ceramic slab articles from a base mix, glass frit for manufacturing the base mix and coloured glass-ceramic slab article so obtained
AssigneeLuca Toncelli
InventorLuca Toncelli
Life of this patent
Estimating the term…
Abstract
Method for manufacturing coloured glass-ceramic slab articles from a base mix, including the steps of (a) preparing a mix comprising a colouring pigment, at least one binder and a preponderant amount of a glass frit having a specific composition, (b) distributing the mix in a forming support, (c) compacting the mix, (d) drying the mix, (e) sintering the compacted and dried mix by firing to obtain a slab article, and (f) cooling the articles under conditions such as to prevent—even partial—devitrification and/or crystallization of the glass frit. Also relating to a glass frit for manufacturing base mixes and a coloured glass-ceramic slab article obtained from the base mix.
Claims21
A method for manufacturing coloured glass-ceramic slab articles from a base mix, comprising the following steps:
- (a) preparing a mix comprising a preponderant amount, greater than 45% by weight, of a glass frit, at least one binder and a colouring agent or pigment;
- (b) distributing the mix in a support or in a forming mould;
- (c) compacting the mix contained in the support or in the mould;
- (d) drying the compacted mix;
- (e) sintering the compacted and dried mix by firing and obtaining the glass-ceramic slab article;
- and
- (f) cooling the article obtained from the firing under conditions which avoid a devitrification and/or crystallization, even only partial, of the glass frit;
- characterized in that the glass frit comprises:
- a weight amount of silica (SiO2) comprised between 55% and 62% relative to an overall weight of the frit;
- a weight amount of alumina (Al2O3) comprised between 16% and 22% relative to the overall weight of the frit;
- a weight amount of sodium oxide (Na2O) comprised between 0.3%, and 3% relative to the overall weight of the frit;
- a weight amount of potassium oxide (K2O) comprised between 2% and 6% relative to the overall weight of the frit;
- a weight amount of calcium oxide (CaO) comprised between 12% and 18% relative to the overall weight of the frit;
- and
- a weight amount of magnesium oxide (MgO) comprised between 0.4% and 3% relative to the overall weight of the frit.
A glass frit for manufacturing a base mix intended for the manufacture of glass-ceramic slab articles, comprising:
- a weight amount of silica (SiO2) comprised between 55% and 62% relative to an overall weight of the frit;
- a weight amount of alumina (Al2O3) comprised between 16% and 22% relative to the overall weight of the frit;
- a weight amount of sodium oxide (Na2O) comprised between 0.3% and 3% relative to the overall weight of the frit;
- a weight amount of potassium oxide (K2O) comprised between 2% and 6% relative to the overall weight of the frit;
- a weight amount of calcium oxide (CaO) comprised between 12% and 18% relative to the overall weight of the frit;
- and
- a weight amount of magnesium oxide (MgO) comprised between 0.4% and 3% relative to the overall weight of the frit;
- wherein the glass frit is at least partially resistant to one or more of devitrification and crystallization.
Dependencies are inferred from the claim text.