Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
189 words
Method of manufacturing a shadow mask comprising the steps of: (a) covering a thin metallic plate, on each a first and second side of said plate, with an etchant resistant film, said film having openings therethrough of predetermined size, which openings are aligned from said first to said second side; (b) in a first etching step, etching said first side of said plate so as to form recesses therein; (c) applying an etchant resistant material to said first side of said plate so as to completely cover said side, including said recesses; (d) in a second etching step, etching said second side of said plate so as to etch exposed portions thereof until the bottom of the etchant resistant material which has been applied to said first side is exposed, thereby forming a number of perforations through said sheet; (e) removing both the etchant resistant material and the etchant resistant film from said first and second sides of the plate, respectively; and (f) in a third etching step, etching both of said first and second sides so as to form regularly arranged perforations of uniform cross-sectional shape and area.
Claim 2
Dependent Claim
189 words
Method of manufacturing a shadow mask comprising the steps of: (a) covering a thin metallic plate, on each a first and second side of said plate, with an etchant resistant film, said film having openings therethrough of predetermined size, which openings are aligned from said first to said second side; (b) in a first etching step, etching said first side of said plate so as to form recesses therein; (c) applying an etchant resistant material to said first side of said plate so as to completely cover said side, including said recesses; (d) in a second etching step, etching said second side of said plate so as to etch exposed portions thereof until the bottom of the etchant resistant material which has been applied to said first side is exposed, thereby forming a number of perforations through said sheet; (e) removing both the etchant resistant material and the etchant resistant film from said first and second sides of the plate, respectively; and (f) in a third etching step, etching both of said first and second sides so as to form regularly arranged perforations of uniform cross-sectional shape and area.
Claim 3
Dependent Claim
16 words
Method according to claim 1 wherein said third etching step is performed by a dipping method.
Claim 4
Dependent Claim
23 words
Method according to claim 1 wherein said second side of said thin metallic plate is completely covered before said first side is etched.
Claim 5
Dependent Claim
30 words
Method according to claim 1 further comprising the step of removing the etchant resistant film from said first side after said first etching before said etchant resistant material is applied.
Claim 6
Dependent Claim
20 words
A method according to claim 1, wherein the third etching is performed by a dipping method in an etchant tank.
Claim 7
Dependent Claim
20 words
A method according to claim 5, wherein the dipping method is performed while agitating the etchant in the etchant tank.
Claim 8
Dependent Claim
15 words
A method according to claim 6, wherein the agitating is performed by a supersonic wave.
Claim 9
Dependent Claim
16 words
A method according to claim 5, wherein the third etching is performed by an electrolytic etching.
Claim 10
Dependent Claim
16 words
A method according to claim 1, wherein the third etching is performed by a spray etching.
Claim 11
Dependent Claim
28 words
Method according to claim 1 wherein said etchant resistant material applied to said first side after said first etching completely fills the recesses formed in said first side.
Claim 12
Dependent Claim
35 words
Method according to claim 1 wherein the recesses formed in said first etching step are of smaller cross-sectional area as measured at the surface of the plate than those recesses formed on said second side.
Claim 13
Dependent Claim
224 words
Method of manufacturing a shadow mask comprising the steps of: (a) covering a thin metallic plate, on each a first and second side thereof with an etchant resistant film, said film having openings therethrough of a predetermined size, which openings are aligned from said first to said second side; (b) in a first etching step, etching said first side of said plate so as to form recesses therein; (c) removing said etchant resistant film from said first side which has been etched; (d) applying an etchant resistant material to said first side of said plate so as to completely cover said side and fill said recesses; (e) in a second etching step, etching said second side of said plate so as to etch exposed portions thereof until the bottom of the etchant resistant material is exposed, thereby forming a number of perforations through said sheet, the recesses formed in the first etching step being of smaller cross-sectional area than those formed in this second etching step as measured at the surface of each side; (f) removing both the etchant resistant material and the etchant resistant film from said first and second sides of the plate, respectively; and (g) in a third etching step, etching both of said first and second sides so as to form regularly arranged perforations of uniform cross-sectional shape and area.
Claim 14
Dependent Claim
224 words
Method of manufacturing a shadow mask comprising the steps of: (a) covering a thin metallic plate, on each a first and second side thereof with an etchant resistant film, said film having openings therethrough of a predetermined size, which openings are aligned from said first to said second side; (b) in a first etching step, etching said first side of said plate so as to form recesses therein; (c) removing said etchant resistant film from said first side which has been etched; (d) applying an etchant resistant material to said first side of said plate so as to completely cover said side and fill said recesses; (e) in a second etching step, etching said second side of said plate so as to etch exposed portions thereof until the bottom of the etchant resistant material is exposed, thereby forming a number of perforations through said sheet, the recesses formed in the first etching step being of smaller cross-sectional area than those formed in this second etching step as measured at the surface of each side; (f) removing both the etchant resistant material and the etchant resistant film from said first and second sides of the plate, respectively; and (g) in a third etching step, etching both of said first and second sides so as to form regularly arranged perforations of uniform cross-sectional shape and area.