Process for producing a laminated glass pane, especially for a motor vehicle

Claim 2

A process for producing a curved glass laminate, comprising the steps of: (a) forming a screen-printable enamel ink consisting essentially of a glass-flux paste, at least one ceramic pigment, a binder forming component and an organic screen-printing oil volatile at a temperature below 300° C.; (b) screen-printing said enamel ink in a predetermined pattern on one side of a first flat glass pane; (c) drying said ink in said pattern at a drying temperature at which said screen-printing oil is volatile and below 300° C. to evaporate said screen-printing oil from the ink in said pattern and dry said pattern without firing of said enamel ink; (d) placing said pane with the dry pattern and another glass pane on top of one another with said other glass pane lying against said one side to produce a paired stack of said panes and heating said stack to a temperature sufficient to soften the glass of said panes, and bending said stack with at least a single curvature at a pane-deformation temperature sufficient to effect bending of said panes and baking of the dry pattern only on said one side of said first pane simultaneously with the bending to produce curved panes in said stack; (e) separating said curved panes from one another; (f) interposing between the separated panes a plastic sheet bondable to said panes and forming another stack of said panes with said plastic sheet between them; and (g) heating said other stack to simultaneously bend said panes and said plastic sheet to effect a double curvature and to bond said other stack together into said curved glass laminate.

Claim 3

The process defined in claim 1 wherein said curved glass laminate is an automotive windshield and said first glass pane is an outer pane of said windshield and said pattern is screen printed on a surface of said outer pane facing said plastic sheet, said pattern being applied at least along an edge of the windshield.

Claim 4

The process defined in claim 2 wherein a respective said pattern is applied to each of said panes at surfaces thereof facing said plastic sheet.

Claim 5

The process defined in claim 2 wherein said binder-forming component includes a silica gel.

Claim 6

The process defined in claim 4 wherein said silica gel is selected from the group which consists of: tetramethylorthosilicate, tetraethylorthosilicate, tetra-n-propylsilicate, tetramethylglycolsilicate, ethylpolysilicate, silicic-acid esters, ethylglycol-free silicic acid binders, modified silicic acid esters, butylglycolsilicate, and mixtures thereof.

Claim 7

The process defined in claim 4 wherein said ink includes a metal alcoholate.

Claim 8

The process defined in claim 6 wherein said metal alcoholate is an alcoholate of aluminum, titanium, zirconium, boron or a mixture thereof.

Claim 9

The process defined in claim 4 wherein an inorganic source of oxygen is included in said ink.

Claim 10

The process defined in claim 8 wherein said source is selected from the group which consists of lead dioxide, minium (red lead), manganese oxide, and mixtures thereof.

Claim 11

The process defined in claim 4 wherein said screen-printing oil is selected from the group which consists of terpine oil, ethylene glycol and mixtures thereof.

Claim 12

The process defined in claim 10 wherein said screen-printing oil is terpine oil.

Claim 13

The process defined in claim 10 wherein said screen-printing oil is ethylene glycol.

Claim 14

An automotive windshield made by the process of claim 4.

Claim 15

A process for producing a curved glass laminate, comprising the steps of: (a) forming a screen-printable enamel ink consisting essentially of a glass-flux paste, at least ceramic pigment, a binder-forming component containing a metal alcoholate selected from the group which consists of aluminum, titanium, zirconium and boron alcoholates, and an organic screen-printing oil volatile at a temperature below 300° C. and selected from the group which consists of terpine oil, ethylene glycol and mixtures thereof; (b) screen-printing said enamel ink in a predetermined pattern on one side of a first flat glass pane; (c) drying said ink in said pattern at a drying temperature at which said screen-printing oil is volatile and below 300° C. to evaporate said screen-printing oil from the ink in said pattern and dry said pattern without firing of said enamel ink; (d) placing said pane with the dry pattern and another glass pane on top of one another with said other glass pane lying against said one side to produce a paired stack of said panes and heating said stack to a temperature sufficient to soften the glass of said panes, and bending said stack with at least a single curvature at a pane-deformation temperature sufficient to effect bending of said panes and baking of the dry pattern on said one of said panes only simultaneously with the bending to produce curved panes in said stack; (e) separating said curved panes from one another; (f) interposing between the separated panes a plastic sheet bondable to said panes and forming another stack of said panes with said plastic sheet between them; and (g) heating said other stack to bond said panes and said plastic sheet into said curved glass laminate.

Claim 16

A process for producing a curved glass laminate, comprising the steps of: (a) forming a screen-printable enamel ink consisting essentially of a glass-flux paste, at least ceramic pigment, a binder-forming component containing a metal alcoholate selected from the group which consists of aluminum, titanium, zirconium and boron alcoholates, and an organic screen-printing oil volatile at a temperature below 300° C. and selected from the group which consists of terpine oil, ethylene glycol and mixtures thereof; (b) screen-printing said enamel ink in a predetermined pattern on one side of a first flat glass pane; (c) drying said ink in said pattern at a drying temperature at which said screen-printing oil is volatile and below 300° C. to evaporate said screen-printing oil from the ink in said pattern and dry said pattern without firing of said enamel ink; (d) placing said pane with the dry pattern and another glass pane on top of one another with said other glass pane lying against said one side to produce a paired stack of said panes and heating said stack to a temperature sufficient to soften the glass of said panes, and bending said stack with at least a single curvature at a pane-deformation temperature sufficient to effect bending of said panes and baking of the dry pattern on said one of said panes only simultaneously with the bending to produce curved panes in said stack; (e) separating said curved panes from one another; (f) interposing between the separated panes a plastic sheet bondable to said panes and forming another stack of said panes with said plastic sheet between them; and (g) heating said other stack to bond said panes and said plastic sheet into said curved glass laminate.