Mineral ink for inkjet printing on a mineral substrate
A mineral ink for inkjet printing on a mineral substrate, includes a glass frit, an organic solvent, a dispersant, a surfactant and a glass fit including the following constituents in the weight limits defined below expressed as percentages by weight of the glass frit: 35 to 50% of SiO 2 , 15 to 25% of Al 2 O 3 , 1.5 to 4% of Li 2 O, 22 to 32% of B 2 O 3 , 0 to 2% of Na 2 O, 2 to 5% of K 2 O, 1 to 5% of CaO, 1 to 4% of ZrO 2 .
1 . A mineral ink comprising:
a glass frit,
an organic solvent,
a dispersant, and
a surfactant,
wherein the glass frit comprises the following constituents in the weight limits defined below expressed as percentages by weight of the glass frit:
35 to 50% of SiO 2 ,
15 to 25% of Al 2 O 3 ,
1.5 to 4% of Li 2 O,
24 to 32% of B 2 O 3 ,
0 to 2% of Na 2 O,
2 to 5% of K 2 O,
1 to 5% of CaO,
1 to 4% of ZrO 2 ,
wherein the mineral ink has a viscosity and particle size distribution suitable for inkjet printing on a mineral substrate, and
wherein the mineral ink has a viscosity between 22 and 100 mPa·s at 25° C.
2 . The mineral ink as claimed in claim 1 , further comprising a mineral pigment.
3 . The mineral ink as claimed in claim 2 , wherein the sum of the percentages by weight of the glass frit and of the mineral pigment represents 50 to 80% by weight of the mineral ink.
4 . The mineral ink as claimed in claim 2 , wherein the percentage by weight of the glass frit represents 65% to 90% by weight of the sum of the weight percentages of the glass frit and of the mineral pigment.
5 . The mineral ink as claimed in claim 1 , wherein the organic solvent represents 70 to 90% by weight of the sum of the percentages by weight of the organic solvent, the dispersant and the surfactant.
6 . The mineral ink as claimed in claim 1 , wherein the organic solvent is an organic compound that is liquid at ambient temperature or a mixture of organic compounds that are liquid at ambient temperature comprising at least one alcohol functional group.
7 . The mineral ink as claimed in claim 1 , wherein the dispersant is a copolymer or a mixture of copolymers comprising at least one acid functional group.
8 . The mineral ink as claimed in claim 1 , wherein the surfactant is a polyether, or a polyether-modified polysiloxanes or a mixture of polyethers.
9 . The mineral ink as claimed in claim 1 , wherein the D90 of a particle size distribution of the mixture of the glass frit and the mineral pigment is between 1 μm and 2 μm.
10 . A method for manufacturing a mineral ink comprising the following steps:
a. providing a glass frit which comprises the following constituents in the weight limits defined below expressed as percentages by weight of the glass frit:
35 to 50% of SiO 2 ,
15 to 25% of Al 2 O 3 ,
1.5 to 4% of Li 2 O,
24 to 32% of B 2 O 3 ,
0 to 2% of Na 2 O,
2 to 5% of K 2 O,
1 to 5% of CaO,
1 to 4% of ZrO 2 ;
b. mixing the glass frit with a mineral pigment;
c. adding an organic solvent and a dispersant to the mixture obtained in step (b);
d. recirculation milling of the mixture obtained in step (c) until the D90 of the particle size distribution of the mixture of the glass frit and the mineral pigment is between 1 and 2 μm;
e. adding a surfactant to the milled preparation obtained in step (d),
wherein the mineral ink has a viscosity and particle size distribution suitable for inkjet printing on a mineral substrate, and
wherein the mineral ink has a viscosity between 22 and 100 mPa·s at 25° C.
11 . A process for manufacturing an enameled glass-ceramic plate comprising the following steps:
a. providing a plate of glass-ceramic parent glass;
b. depositing a green enamel on the surface of the plate of parent glass via a method of inkjet printing of the mineral ink as claimed in claim 1 ;
c. heat treating the plate of glass-ceramic parent glass comprising the green enamel according to the following ceramization cycle:
i. a nucleation hold between 650° C. and 860° C., for 15 minutes to 4 hours,
ii. a growth hold between 860° C. and 1100° C., for 10 minutes to 2 hours.
12 . The process for manufacturing an enameled glass-ceramic plate as claimed in claim 11 , wherein the inkjet printing method is a drop-on-demand type inkjet printing method.
13 . The process for manufacturing an enameled glass-ceramic plate as claimed in claim 11 , wherein the plate of glass-ceramic parent glass is formed by a lithium aluminosilicate glass comprising the following constituents in the weight limits defined below expressed as percentages by weight of the glass:
SiO 2
52-75%,
Al 2 O 3
12-27%,
Li 2 O
1.5-5.5%,
Na 2 O
0-3%,
K 2 O
0-3%,
CaO
0-5%,
MgO
0-5%,
SrO
0-5%,
BaO
0-5%,
ZnO
0-5%,
TiO 2
1-6%,
ZrO 2
0-3%,
P 2 O 5
0-8%.
14 . An enameled glass-ceramic plate obtained using the process as claimed in claim 11 .
15 . A cooking device comprising the enameled glass-ceramic plate as claimed in claim 14 .