The present invention relates to a laser cutting technology for cutting and separating thin substrates of transparent materials, for example to cutting of display glass compositions mainly used for production of Thin Film Transistors (TFT) devices. The described laser process can be used to make straight cuts, for example at a speed of >1 m/sec, to cut sharp radii outer corners (<1 mm), and to create arbitrary curved shapes including forming interior holes and slots. A method of laser processing an alkaline earth boro-aluminosilicate glass composite workpiece includes focusing a pulsed laser beam into a focal line. The focal line is directed into the glass composite workpiece, generating induced absorption within the material. The workpiece and the laser beam are translated relative to each other to form a plurality of defect lines along a contour, with adjacent defect lines have a spacing of 0.1-20 microns.

An alkali-free glass substrate which is a glass substrate includes, as represented by molar percentage based on oxides, 0.1% to 10% of ZnO. The alkali-free glass substrate has an average coefficient of thermal expansion α.sub.50/100 at 50 to 100° C. of from 2.70 ppm/° C. to 3.20 ppm/° C., an average coefficient of thermal expansion α.sub.200/300 at 200 to 300° C. of from 3.45 ppm/° C. to 3.95 ppm/° C., and a value α.sub.200/300/α.sub.50/100 obtained by dividing the average coefficient of thermal expansion α.sub.200/300 at 200 to 300° C. by the average coefficient of thermal expansion α.sub.50/100 at 50 to 100° C. of from 1.20 to 1.30.

An apparatus and a method for continuously manufacturing tempered glass are provided. The tempered glass is continuously manufactured by transferring the raw glass in one direction, spraying a boiled potassium nitrate solution to the raw glass to reinforce the raw glass, and recovering and reusing the potassium nitrate solution from the raw glass. This invention can reduce the time to manufacture tempered glass since you can manufacture tempered glass consecutively, and the cost of purchasing potassium nitrate solutions can be reduced, which has an economic advantage. Since the raw glass is preheated, strengthened and annealed by divided sections of preheating, strengthening and annealing section in one furnace, it is less likely that impurities will be attached to the raw glass due to low external exposure during each process movement, thus preventing deterioration of quality.

An apparatus and a method for continuously manufacturing tempered glass are provided. The tempered glass is continuously manufactured by transferring the raw glass in one direction, spraying a boiled potassium nitrate solution to the raw glass to reinforce the raw glass, and recovering and reusing the potassium nitrate solution from the raw glass. This invention can reduce the time to manufacture tempered glass since you can manufacture tempered glass consecutively, and the cost of purchasing potassium nitrate solutions can be reduced, which has an economic advantage. Since the raw glass is preheated, strengthened and annealed by divided sections of preheating, strengthening and annealing section in one furnace, it is less likely that impurities will be attached to the raw glass due to low external exposure during each process movement, thus preventing deterioration of quality.

An apparatus for manufacturing a glass article includes a plurality of side portions spaced apart from each other; and a plurality of heat supply portions disposed on each of the side portions; where the side portions adjacent to each other are disposed to face each other, and a glass is allowed to be disposed between the adjacent side portions.

The present disclosure relates to a process for cutting and separating arbitrary shapes of thin substrates of transparent materials, particularly tailored composite fusion drawn glass sheets, and the disclosure also relates to a glass article prepared by the method. The developed laser method can be tailored for manual separation of the parts from the panel or full laser separation by thermally stressing the desired profile. The self-separation method involves the utilization of an ultra-short pulse laser that can be followed by a CO.sub.2 laser (coupled with high pressure air flow) for fully automated separation.

The present disclosure relates to a process for cutting and separating arbitrary shapes of thin substrates of transparent materials, particularly tailored composite fusion drawn glass sheets, and the disclosure also relates to a glass article prepared by the method. The developed laser method can be tailored for manual separation of the parts from the panel or full laser separation by thermally stressing the desired profile. The self-separation method involves the utilization of an ultra-short pulse laser that can be followed by a CO.sub.2 laser (coupled with high pressure air flow) for fully automated separation.

An alkali-free glass substrate which is a glass substrate includes, as represented by molar percentage based on oxides, 0.1% to 10% of ZnO. The alkali-free glass substrate has an average coefficient of thermal expansion .sub.50/100 at 50 to 100 C. of from 2.70 ppm/ C. to 3.20 ppm/ C., an average coefficient of thermal expansion .sub.200/300 at 200 to 300 C. of from 3.45 ppm/ C. to 3.95 ppm/ C., and a value .sub.200/300/.sub.50/100 obtained by dividing the average coefficient of thermal expansion .sub.200/300 at 200 to 300 C. by the average coefficient of thermal expansion .sub.50/100 at 50 to 100 C. of from 1.20 to 1.30.

The present disclosure relates to a process for cutting and separating arbitrary shapes of thin substrates of transparent materials, particularly tailored composite fusion drawn glass sheets, and the disclosure also relates to a glass article prepared by the method. The developed laser method can be tailored for manual separation of the parts from the panel or full laser separation by thermally stressing the desired profile. The self-separation method involves the utilization of an ultra-short pulse laser that can be followed by a CO.sub.2 laser (coupled with high pressure air flow) for fully automated separation.

The present disclosure relates to a process for cutting and separating arbitrary shapes of thin substrates of transparent materials, particularly tailored composite fusion drawn glass sheets, and the disclosure also relates to a glass article prepared by the method. The developed laser method can be tailored for manual separation of the parts from the panel or full laser separation by thermally stressing the desired profile. The self-separation method involves the utilization of an ultra-short pulse laser that can be followed by a CO.sub.2 laser (coupled with high pressure air flow) for fully automated separation.