Back to results
US 4,905,020 AGranted
Thermal print head
AssigneeTokyo Electric Co., Ltd.
InventorsYozo Kobayashi, Norihito Mochizuki, Hisao Suzuki, Shinichi Mizushima
Life of this patent
Estimating the term…
Abstract
A thermal print head comprising a sequential laminated arrangement of an insulating substrate, a heating resistance layer, an electrode layer formed in a predetermined pattern, and a protective layer. The protective layer is formed of a mixture of Al.sub.2 O.sub.3 as a principal component, and SiO.sub.2. The protective layer has satisfactory heat resistance, abrasion resistance, crack resistance, moisture resistance and chemical stability.
Claims9
A thermal print head comprising:
- an insulating substrate;
- a heating resistance layer formed over the insulating substrate;
- an electrode layer formed over the heating resistance layer in a predetermined pattern;
- and a protective layer formed over the electrode layer;
- characterized in that the protective layer is formed of a mixture of Al.sub.2 O.sub.3 as a principal component, and SiO.sub.2 in the range of 20 to 45 mol %.
2 more elements
A thermal print head comprising:
- an insulating substrate;
- a heating resistance layer formed over the insulating substrate;
- an electrode layer formed in a predetermined pattern over the heating resistance layer;
- and a protective layer formed over the electrode layer;
- characterized in that the protective layer is formed of a mixture containing Al.sub.2 O.sub.3 and SiO.sub.2 as principal components and contains nitrogen in the surface thereof.
2 more elements
A thermal print head comprising:
- an insulating substrate;
- a heating resistance layer formed over the insulating substrate;
- an electrode layer formed in a predetermined pattern over the heating resistance layer;
- and a protective layer formed over the electrode layer;
- characterized in that protective layer is formed of a mixture containing Al.sub.2 O.sub.3, SiO.sub.2 and SiC as principal components.
2 more elements
A thermal print head comprising:
- an insulating substrate;
- a heating resistance layer formed over the insulating substrate;
- an electrode layer formed in a predetermined pattern over the heating resistance layer;
- and a protective layer formed over the electrode layer;
- characterized in that the heating resistance layer is formed of a thin oxide film containing ruthenium as a first principal component, and the protective layer is a composite layer formed of a laminated layer of a first layer formed of a mixture of Al.sub.2 O.sub.3 and SiO.sub.2 and a second layer formed of SiC.
2 more elements
Dependencies are inferred from the claim text.