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US4191403A Expired / Lapsed US ⏱️ 0.0 years remaining

Donor material for carbonless copying

Assignee: Stora Feldmuehle AG
•
Filing: 1978-09-13
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Granted: 1980-03-04
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Expires: 1998-09-13
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Abstract

Abstract In a donor material for carbonless copying which mainly consists of a carrier sheet and a multiplicity of frangible microcapsules containing a suitable dye precursor in a liquid medium and secured to one face of the sheet, spacer particles of soybean protein are interspersed in a relatively small amount between the microcapsules and project beyond the microcapsules away from the carrier sheet to protect the microcapsules against premature fracture.

Inventors

  • 👤 Guido Dessauer
  • 👤 Kurt Riecke
  • 👤 Ferdinand Land

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 03:00
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/124; B41M5/1243; Y; Y10; Y10S; Y10S428/00; Y10S428/914; Y10T; Y10T428/00; Y10T428/25; Y10T428/254; Y10T428/29; Y10T428/2982; Y10T428/2984

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 105 words
In a donor material for carbonless copying including a carrier sheet, a multiplicity of frangible microcapsules secured to one major face of said sheet, each microcapsule containing a dye precursor in a liquid medium, and discrete spacer particles interposed between said microcapsules and projecting beyond said microcapsules away from said face for protecting the microcapsules against premature fracture, the improvement which resides in said spacer particles consisting essentially of a vegetal protein insoluble in water and amounting to 10 to 50% of the weight of said microcapsules, the average size of said particles being between two and three times the average size of said microcapsules.
Claim 2
Dependent Claim 105 words
In a donor material for carbonless copying including a carrier sheet, a multiplicity of frangible microcapsules secured to one major face of said sheet, each microcapsule containing a dye precursor in a liquid medium, and discrete spacer particles interposed between said microcapsules and projecting beyond said microcapsules away from said face for protecting the microcapsules against premature fracture, the improvement which resides in said spacer particles consisting essentially of a vegetal protein insoluble in water and amounting to 10 to 50% of the weight of said microcapsules, the average size of said particles being between two and three times the average size of said microcapsules.
Claim 3
Dependent Claim 14 words
In a material as set forth in claim 1, said protein being soybean protein.
Claim 4
Dependent Claim 18 words
In a donor material as set forth in claim 1, said vegetal protein being partly cross-linked by formaldehyde.
Claim 5
Dependent Claim 48 words
The donor material of claim 1 wherein the microcapsule size varies between a diameter of 2 and 10 microns and the average diameter is 6 microns and the spacer particles vary between the diameter of 4 to 30 microns and the average size is 12 to 18 microns.
Claim 6
Dependent Claim 48 words
The donor material of claim 1 wherein the microcapsule size varies between a diameter of 5 to 20 microns and the average diameter is 12.5 microns and the spacer particles vary between a diameter of 10 to 60 microns and the average size is 25 to 37.5 microns.

References Cited (Backward Citations)

US3900671A Cited
US3996061A Cited
US3996060A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1983-03-04 1983-09-03 1984-03-04 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1987-03-04 1987-09-03 1988-03-04 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1991-03-04 1991-09-03 1992-03-04 $7700.00 Window Closed / Lapsed

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