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US4359516A Expired / Lapsed US ⏱️ 0.0 years remaining

Magnetic resist printing process, composition, and apparatus

Assignee: EIDP Inc
•
Filing: 1980-11-21
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Granted: 1982-11-16
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Expires: 2000-11-21
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Abstract

Abstract A process of forming an image of toner on a latent magnetic image in a magnetic member followed by direct transfer to and coalescence on a surface to form a resist is disclosed. The surface portion not protected by the transferred resist toner image is then permanently modified by etching or plating. Chemically milled shapes are prepared as well as printed circuits and printing plates. The printed circuits may be formed by (1) etching away areas of a metal surface not protected by the resist, (2) electroless plating on areas not protected by the resist or (3) electroplating areas of a metal surface not protected by the resist, removing the resist, and in the case of (2) and (3), etching away the metal previously covered by the resist. An especially useful toner which forms a resist composition comprises a binder of thermoplastic resin and plasticizer and magnetic material present in the binder, compounded to have a tack transfer temperature of no greater than 110° C.

Inventors

  • 👤 George R. Nacci
  • 👤 Donald G. Pie

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 19:50
CPC Classifications
G; G03; G03G; G03G19/00; H; H05; H05K; H05K3/00; H05K3/02; H05K3/06; H05K3/061; H05K3/065; Y; Y10; Y10S; Y10S430/00; Y10S430/001; Y10S430/104

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 205 words
A dry particulate resist composition of particles having an average size of 1 to 30 μm, a melt index of 1 to 100 and a glass transition temperature from 25° C. to 100° C., for substantially instantaneous application to a heated surface to form a resist image capable of withstanding modification of an exposed area of said surface, comprising (a) a coalescible binder consisting essentially of a thermoplastic resin having a weight average molecular weight of at least 1,000 and less than 50,000 and 2 to 40% of plasticizer based on the weight of said binder, said plasticizer having a boiling point above 200° C., and (b) magnetic material having an average particle size of less than 6 μm present in said binder rendering the particles of said composition magnetically attractible, said magnetic material constituting from 40 to 80% by weight of the combination of (a) plus (b) and said binder constituting the remainder, the combination of said binder and said magnetic material in said particles rendering them substantially nonblocking at ordinary room temperature and adherent to said surface and coalescible thereon upon said application to said surface to form a resist image, whereby said composition has a tack transfer window greater than 8° C.
Claim 2
Dependent Claim 205 words
A dry particulate resist composition of particles having an average size of 1 to 30 μm, a melt index of 1 to 100 and a glass transition temperature from 25° C. to 100° C., for substantially instantaneous application to a heated surface to form a resist image capable of withstanding modification of an exposed area of said surface, comprising (a) a coalescible binder consisting essentially of a thermoplastic resin having a weight average molecular weight of at least 1,000 and less than 50,000 and 2 to 40% of plasticizer based on the weight of said binder, said plasticizer having a boiling point above 200° C., and (b) magnetic material having an average particle size of less than 6 μm present in said binder rendering the particles of said composition magnetically attractible, said magnetic material constituting from 40 to 80% by weight of the combination of (a) plus (b) and said binder constituting the remainder, the combination of said binder and said magnetic material in said particles rendering them substantially nonblocking at ordinary room temperature and adherent to said surface and coalescible thereon upon said application to said surface to form a resist image, whereby said composition has a tack transfer window greater than 8° C.
Claim 3
Dependent Claim 17 words
The composition of claim 1 wherein the magnetic material has a coercivity of less than 400 oersteds.
Claim 4
Dependent Claim 18 words
The resist composition of claim 1 having a transfer temperature in the range of 50° to 120° C.
Claim 5
Dependent Claim 15 words
The resist composition of claim 1 having a melt index of from 1 to 50.
Claim 6
Dependent Claim 17 words
The resist composition of claim 1 having a glass transition temperature of from 25° to 80° C.
Claim 7
Dependent Claim 23 words
The resist composition of claim 1 wherein said binder is soluble or swellable in methylene chloride or aqueous alkali at ordinary room temperature.
Claim 8
Dependent Claim 27 words
The resist composition of claim 1 wherein said magnetic material is substantially non-porous and isometric in particle shape having an average particle size of 0.1 to 1μ.
Claim 9
Dependent Claim 15 words
The resist composition of claim 1 wherein said magnetic material is a non-conductor of electricity.
Claim 10
Dependent Claim 20 words
The resist composition of claim 1 wherein said thermoplastic resin has a molecular weight which gives it Newtonian flow character.
Claim 11
Dependent Claim 12 words
The resist composition of claim 1 wherein said thermoplastic resin is polyester.
Claim 12
Dependent Claim 13 words
The resist composition of claim 1 wherein said thermoplastic resin is acrylic polymer.
Claim 13
Dependent Claim 17 words
The resist composition of claim 11 wherein said resin has an acid number of at least 25.
Claim 14
Dependent Claim 156 words
A dry resist composition of particles having an average particle size of 1 to 30 μm, and comprising 35 to 65% by wt. of coalescible binder component and 45 to 65% by weight based on the weight of the composition of magnetic material having an average particle size up to 6 μm present in said particles, said binder component composed of thermoplastic polyester resin and 5 to 15% by wt. of plasticizer for said resin based on the total weight of said binder component, said composition being non-blocking at ordinary room temperature and resistant to aqueous FeCl 3 etchant and having a melt index of 2 to 100, glass transition temperature of 25° to 110° C. and tack transfer temperature of 50° to 110° C. and tack transfer window of at least 20° C., said resin having a weight average molecular weight of 1,000 to 50,000 and being adherent to copper at said tack transfer temperature.
Claim 15
Dependent Claim 156 words
A dry resist composition of particles having an average particle size of 1 to 30 μm, and comprising 35 to 65% by wt. of coalescible binder component and 45 to 65% by weight based on the weight of the composition of magnetic material having an average particle size up to 6 μm present in said particles, said binder component composed of thermoplastic polyester resin and 5 to 15% by wt. of plasticizer for said resin based on the total weight of said binder component, said composition being non-blocking at ordinary room temperature and resistant to aqueous FeCl 3 etchant and having a melt index of 2 to 100, glass transition temperature of 25° to 110° C. and tack transfer temperature of 50° to 110° C. and tack transfer window of at least 20° C., said resin having a weight average molecular weight of 1,000 to 50,000 and being adherent to copper at said tack transfer temperature.

References Cited (Backward Citations)

US2297691A Cited
US3239465A Cited
US3558492A Cited
US3681106A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-11-15 1986-05-17 1986-11-16 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-11-15 1990-05-17 1990-11-16 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-11-15 1994-05-17 1994-11-16 $7700.00 Window Closed / Lapsed

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