← Back to Patent Explorer
US3761269A Expired / Lapsed US ⏱️ 0.0 years remaining

I neutralizing spacer element self developing photographic film unit with liquid trap and an alkali

Assignee: Polaroid Corp
•
Filing: 1971-09-27
•
Granted: 1973-09-25
•
Expires: 1991-09-27
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract ARE RETAINED TOGETHER SUBSEQUENT TO PROCESSING AND THE LIQUID TRAPPING AND RETAINING SPACES FORMED BY THE SPACER ELEMENT ARE LOCATED WITHIN THE FILM ASSEMBLAGE VERY CLOSE TO THE AREA CONTAINING THE VISIBLE IMAGE. TO NEUTRALIZE EXCESS PROCESSING LIQUID COLLECTED IN THE TRAPPING SPACES AND PREVENT MIGRATION OF A ALKALI INTO THE IMAGE AREA, THE SPACER ITSELF IS AT LEAST COATED WITH CITRIC ACID ON THE SIDE IN CONTACT WITH WHICH THE PROCESSING LIQUID IS SPREAD. PHOTOGRAPHIC FILM ASSEMBLAGE COMPRISING A PAIR OF SHEET-LIKE ELEMENTS AND A LAYER OF A PHOTOSENSITIVE MATERIAL SANDWICHED BETWEEN THE ELEMENTS INCLUDING AN AREA ADAPTED TO BE EXPOSED AND PROCESSED BY AN AQUEOUS ALKALINE PROCESSING LIQUID SPREAD IN A LAYER BETWEEN THE TWO ELEMENTS TO FORM A VISIBLE TRANSFER IMAGE. THE FILM ASSEMBLAGE INCLUDES A BINDING SHEET SECURED AROUND AND TO THE EXTERIOR OF ADJACENT END SECTIONS OF THE TWO ELEMENTS AND A SPACER FORMED OF A FIBROUS MATERIAL CONTAINED WITHIN THE FILM ASSEMBLAGE BETWEEN THE SHEET-LIKE ELEMENTS AND BINDING SHEET. THE SPACER IS FORMED WITH GAPS WHICH COOPERATE WITH THE ELEMENTS AND BINDING SHEETS TO PROVIDE TRAPPING SPACES FOR COLLECTING AND RETAINING EXCESS PROCESSING LIQUID OVERRUN AS THE END PORTIONS OF THE ELEMENTS ARE MOVED BETWEEN A PAIR OF PRESSURE-APPLYING MEMBERS WHICH SPREAD THE PROCESSING LIQUID. THE TWO SHEETS

Inventors

  • 👤 J Campbell

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 19:51
CPC Classifications
G; G03; G03D; G03D9/00; G03D9/02; G03B; G03B17/00; G03B17/28; G03B17/32; G03B17/34; G03C; G03C8/00; G03C8/42; G03C8/44; G03C8/46; G03C8/52

Claims Analysis

Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.

References Cited (Backward Citations)

No citation records indexed.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1976-09-24 1977-03-26 1977-09-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1980-09-24 1981-03-26 1981-09-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1984-09-24 1985-03-26 1985-09-25 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag