EP0046985A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Ink platen for use in dot printers
Assignee: Bridgestone Corp
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Filing: 1981-08-26
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Granted: —
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Expires: 2001-08-26
Abstract
Abstract The ink platen (10) for use in a dot printer is impregnated with ink and is arranged such that printing needles (12) strike the ink platen (10) through a sheet of paper (11) placed in front of the ink platen (10), whereby ink dots are imprinted on the paper (11) at the points of impact of the printing needles (12) to form a character on the paper (11) in a dot-matrix format. The new ink platen (10) comprises a compressed body of a flexible reticulated polyurethane foam, and said compressed body has a surface hardness of at least 45 degrees and an internal hardness of at least 30 degrees on the hardness scale of a spring type hardness tester (type A) when the hardness is measured by using this A type tester with the method defined in Japanese Industrial Standard K 6301-1975, the surface hardness being higher than the internal hardness.
Inventors
- 👤 Tsuneaki Narumiya
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 23:54
CPC Classifications
B; B41; B41J; B41J11/00; B41J11/02; B41J27/00; B41J27/20
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
153 words
An ink platen for use in a dot printer comprising the ink platen (10; 10'; 10") impregnated with ink and printing needles (5) adapted to strike the ink platen through a sheet of paper (2) placed in front of the ink platen, whereby ink dots are imprinted on the paper at points of impact of the printing needles to form a character on the paper in a dot-matrix format, characterized in that the ink platen (10; 10'; 10") comprises a compressed body (16) of a flexible reticulated polyurethane foam (13), and said compressed body has a surface hardness of at least 45 degrees and an internal hardness of at least 30 degrees on the hardness scale of a spring type hardness tester (type A) when the hardness is measured by using this type tester with the method defined in Japanese Industrial Standard K 6301-1975, the surface hardness being higher than the internal hardness.
Claim 2
Dependent Claim
153 words
An ink platen for use in a dot printer comprising the ink platen (10; 10'; 10") impregnated with ink and printing needles (5) adapted to strike the ink platen through a sheet of paper (2) placed in front of the ink platen, whereby ink dots are imprinted on the paper at points of impact of the printing needles to form a character on the paper in a dot-matrix format, characterized in that the ink platen (10; 10'; 10") comprises a compressed body (16) of a flexible reticulated polyurethane foam (13), and said compressed body has a surface hardness of at least 45 degrees and an internal hardness of at least 30 degrees on the hardness scale of a spring type hardness tester (type A) when the hardness is measured by using this type tester with the method defined in Japanese Industrial Standard K 6301-1975, the surface hardness being higher than the internal hardness.
Claim 3
Dependent Claim
31 words
An ink platen according to claim 1 wherein said compressed body has a surface hardness of at least 60 degrees and an internal hardness of-40 to 90 degrees on said scale.
Claim 4
Dependent Claim
27 words
An ink platen according to claim 1 or 2 wherein the surface hardness is higher than the internal hardness by 15 to 60 degrees on said scale.
Claim 5
Dependent Claim
51 words
An ink platen according to claim 1 wherein said compressed body is formed by heat compressing a flexible reticulated polyurethane foam so that the surface hardness of the compressed body is at least 45 degrees and the internal hardness of the compressed body is at least 30 degrees on said scale.
Claim 6
Dependent Claim
99 words
An ink platen according to claim 1 wherein said compressed body is formed by heat compressing a flexible reticulated polyurethane foam, cutting out of the compressed foam a rectangular body with its thickness substantially perpendicular to the direction of compression, and further heat compressing the cut-out body in its thickness direction, whereby the resulting bidirectionally compressed body has a high surface hardness of at least 45 degrees and a low internal hardness of at least 30 degrees on said scale with the internal cells being elongated in the thickness direction, and hence, perpendicular to the plane of the paper.
Claim 7
Dependent Claim
55 words
An ink platen according to claim 1 wherein said compressed body comprises a compressed soft foam layer having a hardness of at least 30 degrees and a (10a; 19) compressed hard foam layer having a hardness of at least 45 degrees on said scale laminated on at least one surface of the soft foam layer.
References Cited (Backward Citations)
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