Heat-sensitive recording head and method of manufacturing same

Claim 1

A method of manufacturing a heat-sensitive recording head having a plurality of first electrodes and a plurality of second electrodes formed on a substrate, said first electrodes being provided so as to have a recording signal applied thereto, said second electrodes being provided as common electrodes, a heating resistor bridged over the predetermined portions of said first electrodes and said second electrodes to form a plurality of heating portions on said heating resistor, and a protective layer formed so as to protect parts of said first electrodes and said second electrodes and said heating resistor, comprising the steps of: forming said heating resistor by coating said substrate with a resistor paste so as to be bridged over the predetermined portions of said first electrodes and said second electrodes, and drying and baking said paste; forming holes in said heating portions of said heating resistor by using a boring apparatus, while detecting variations, which occur on a basis of the number of said holes, in a resistance value of each of said heating portions; and stopping the hole-making operation of said boring apparatus when the resistance value of each of said heating portions has reached, respectively, a predetermined level, to regulate the resistance value of said heating portions of said heating resistor.

Claim 2

A method of manufacturing a heat-sensitive recording head having a plurality of first electrodes and a plurality of second electrodes formed on a substrate, said first electrodes being provided so as to have a recording signal applied thereto, said second electrodes being provided as common electrodes, a heating resistor bridged over the predetermined portions of said first electrodes and said second electrodes to form a plurality of heating portions on said heating resistor, and a protective layer formed so as to protect parts of said first electrodes and said second electrodes and said heating resistor, comprising the steps of: forming said heating resistor by coating said substrate with a resistor paste so as to be bridged over the predetermined portions of said first electrodes and said second electrodes, and drying and baking said paste; forming holes in said heating portions of said heating resistor by using a boring apparatus, while detecting variations, which occur on a basis of the number of said holes, in a resistance value of each of said heating portions; and stopping the hole-making operation of said boring apparatus when the resistance value of each of said heating portions has reached, respectively, a predetermined level, to regulate the resistance value of said heating portions of said heating resistor.

Claim 7

A method of manufacturing heat-sensitive recording heads, comprising the steps of: forming a plurality of first electrodes and a plurality of second electrodes, said first electrodes being provided so as to have a recording signal selectively applied thereto, said second electrodes being provided as common electrodes, said first electrodes and said second electrodes being formed on a substrate by printing conductive paste to a desired pattern thereon by a screen printing method; forming a heating resistor by coating said substrate with a resistor paste to a desired thickness so that a layer of resistor paste is bridged over the predetermined portions of said first electrodes and said second electrodes, and then drying and baking said resistor paste to form heating portions on bridge sections of said heating resistor; making holes in said heating portions of said heating resistor by using a laser-boring apparatus, while detecting variations, which occur on a basis of the number of said holes, in a resistance value of a heating portion of said heating resistor; stopping the laser-boring operation of said laser-boring apparatus to carry out a regulation of the resistance value of each of said heating portions of said heating resistor when the resistance value of each of said heating portions has reached, respectively, a predetermined level; and forming a protective layer by coating parts of said first electrodes and said second electrodes and said heating resistor with a protective material, and drying and baking said protective layer thus formed.

Claim 8

A method of manufacturing heat-sensitive recording heads, comprising the steps of: forming a plurality of first electrodes and a plurality of second electrodes, said first electrodes being provided so as to have a recording signal selectively applied thereto, said second electrodes being provided as common electrodes, said first electrodes and said second electrodes being formed on a substrate by printing conductive paste to a desired pattern thereon by a screen printing method; forming a heating resistor by coating said substrate with a resistor paste to a desired thickness so that a layer of resistor paste is bridged over the predetermined portions of said first electrodes and said second electrodes, and then drying and baking said resistor paste to form heating portions on bridge sections of said heating resistor; making holes in said heating portions of said heating resistor by using a laser-boring apparatus, while detecting variations, which occur on a basis of the number of said holes, in a resistance value of a heating portion of said heating resistor; stopping the laser-boring operation of said laser-boring apparatus to carry out a regulation of the resistance value of each of said heating portions of said heating resistor when the resistance value of each of said heating portions has reached, respectively, a predetermined level; and forming a protective layer by coating parts of said first electrodes and said second electrodes and said heating resistor with a protective material, and drying and baking said protective layer thus formed.

Claim 15

A method of manufacturing heat-sensitive recording heads, comprising the steps of: forming a plurality of first electrodes and a plurality of second electrodes by printing a conductive paste to a desired pattern on a surface of a substrate by a screen printing method, said first electrodes being provided so as to have a recording signal applied thereto and said second electrodes being provided as common electrodes; forming a heating resistor by coating said surface of said substrate with a resistor paste to a desired thickness so that said paste is bridged over parts of said plurality of first electrodes and said second electrodes, and drying and baking said resistor paste to thereby form heating portions of said heating resistor, said heating portions being sections of said heating resistor which are bridged over said first electrodes and said second electrodes; forming a protective layer by coating said plurality of first electrodes and said second electrodes and said heating resistor with a protective material so as to cover the same therewith, and then drying and baking said protective material; making holes through said protective layer and each of said heating portions of said heating resistor by a laser-boring apparatus while detecting variations, which occur on a basis of a number of said holes, in a resistance value of each of said heating portions; stopping the laser-boring apparatus when said resistance value of each of said heating portions has reached a predetermined level, to thereby regulate said resistance value of each of said heating portions of said heating resistor; and thereafter processing the surface of said protective layer.

Claim 16

A method of manufacturing heat-sensitive recording heads, comprising the steps of: forming a plurality of first electrodes and a plurality of second electrodes by printing a conductive paste to a desired pattern on a surface of a substrate by a screen printing method, said first electrodes being provided so as to have a recording signal applied thereto and said second electrodes being provided as common electrodes; forming a heating resistor by coating said surface of said substrate with a resistor paste to a desired thickness so that said paste is bridged over parts of said plurality of first electrodes and said second electrodes, and drying and baking said resistor paste to thereby form heating portions of said heating resistor, said heating portions being sections of said heating resistor which are bridged over said first electrodes and said second electrodes; forming a protective layer by coating said plurality of first electrodes and said second electrodes and said heating resistor with a protective material so as to cover the same therewith, and then drying and baking said protective material; making holes through said protective layer and each of said heating portions of said heating resistor by a laser-boring apparatus while detecting variations, which occur on a basis of a number of said holes, in a resistance value of each of said heating portions; stopping the laser-boring apparatus when said resistance value of each of said heating portions has reached a predetermined level, to thereby regulate said resistance value of each of said heating portions of said heating resistor; and thereafter processing the surface of said protective layer.

Claim 23

A method of manufacturing a heat-sensitive recording head comprising: a step (a) of forming a plurality of spaced recording electrodes on a major surface of an insulating substrate; a step (b) of forming a plurality of spaced common electrodes on said major surface of said insulating substrate so as to leave a gap between each of said recording electrodes and each of said common electrodes; a step (c) of coating said major surface of said substrate with a resistor paste, drying and baking said resistor paste so as to provide a heating resistor bridging portions of each of said recording electrodes and each of said common electrodes, said heating resistor having a plurality of heating portions, each of said heating portions bridging one of said recording electrodes and one of said common electrodes; a step (d) of boring at least one hole in one of said heating portions while detecting a resistance of said one of said heating portions until said resistance reaches a predetermined value at which time the boring is stopped; a step (e) of repeating said step (d) for each of a plurality of said heating portions; and a step (f) of forming a protective layer over said recording electrodes, said common electrodes and said heating resistor, whereby scatter of resistance values of said heating portions can be minimized.

Claim 24

A method of manufacturing a heat-sensitive recording head comprising: a step (a) of forming a plurality of spaced recording electrodes on a major surface of an insulating substrate; a step (b) of forming a plurality of spaced common electrodes on said major surface of said insulating substrate so as to leave a gap between each of said recording electrodes and each of said common electrodes; a step (c) of coating said major surface of said substrate with a resistor paste, drying and baking said resistor paste so as to provide a heating resistor bridging portions of each of said recording electrodes and each of said common electrodes, said heating resistor having a plurality of heating portions, each of said heating portions bridging one of said recording electrodes and one of said common electrodes; a step (d) of boring at least one hole in one of said heating portions while detecting a resistance of said one of said heating portions until said resistance reaches a predetermined value at which time the boring is stopped; a step (e) of repeating said step (d) for each of a plurality of said heating portions; and a step (f) of forming a protective layer over said recording electrodes, said common electrodes and said heating resistor, whereby scatter of resistance values of said heating portions can be minimized.