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US3909348A Expired / Lapsed US ⏱️ 0.0 years remaining

Urea-formaldehyde pigmentary fillers used in paper

Assignee: Cabot Corp
•
Filing: 1974-09-09
•
Granted: 1975-09-30
•
Expires: 1994-09-09
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Abstract

Abstract This disclosure relates to the use of certain insoluble, infusible, non-porous, particulate urea-formaldehyde polymers having a molar ratio of urea to formaldehyde ranging from about 1:1.3 to about 1:1.8 as pigmentary fillers in the preparation of paper products having improved properties.

Inventors

  • 👤 Peter Economou
  • 👤 John F Hardy
  • 👤 Alfred Renner

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 08:20
CPC Classifications
D; D21; D21H; D21H21/00; D21H21/14; D21H21/28; D21H21/285; D21H17/00; D21H17/20; D21H17/33; D21H17/46; D21H17/47; D21H17/49; D21H17/50; D21H21/50; D21H21/52

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 99 words
A PAPER PRODUCT COMPRISING A PAPER PULP AND AS A PIGMENTARY FILLER AN INSOLUBLE, INFUSIBLE, NON-POROUS, PARTICULATE UREA-FORALDEHYDE POLYMER HAVING A MOLAR RATIO OF UREA TO FORMALDHYDE RANGING FROM ABOUT 1:1.3 TO ABOUT 1:1.8, A BET SPECIFIC SURFACE AREA RANGING FROM ABOUT 5 TO 50 SQUARE METERS PER GRAM, AN ABSORPTION CAPACITY FOR AQUEOUS STARCH SOLUTION RANGING FROM 3.0 TO 8.0 GMS/GM PIGMENT, AND A MEAN AGGLOMERATE SIZE OF 3 TO 12 MICRONS, WHEREIN THE PIGMENTARY FILLER IS PRESENT IN AMOUNTS OF FROM ABOUT 0.5 TO ABOUT 80 PERCENT BY WEIGHT BASED ON THE WEIGHT OF THE DRY PULP.
Claim 2
Dependent Claim 99 words
A PAPER PRODUCT COMPRISING A PAPER PULP AND AS A PIGMENTARY FILLER AN INSOLUBLE, INFUSIBLE, NON-POROUS, PARTICULATE UREA-FORALDEHYDE POLYMER HAVING A MOLAR RATIO OF UREA TO FORMALDHYDE RANGING FROM ABOUT 1:1.3 TO ABOUT 1:1.8, A BET SPECIFIC SURFACE AREA RANGING FROM ABOUT 5 TO 50 SQUARE METERS PER GRAM, AN ABSORPTION CAPACITY FOR AQUEOUS STARCH SOLUTION RANGING FROM 3.0 TO 8.0 GMS/GM PIGMENT, AND A MEAN AGGLOMERATE SIZE OF 3 TO 12 MICRONS, WHEREIN THE PIGMENTARY FILLER IS PRESENT IN AMOUNTS OF FROM ABOUT 0.5 TO ABOUT 80 PERCENT BY WEIGHT BASED ON THE WEIGHT OF THE DRY PULP.
Claim 3
Dependent Claim 27 words
A paper product as defined in claim 1 wherein the urea-formaldehyde polymer has an absorption capacity for aqueous starch solution ranging from 4.0 to 8.0 gms/gm pigment.
Claim 4
Dependent Claim 37 words
A paper product as defined in claim 1 wherein the urea-formaldehyde polymer has an absorption capacity for aqueous starch solution ranging from 4.5 to 7.3 gms/gm pigment and a mean agglomerate size of 5 to 10 microns.
Claim 5
Dependent Claim 46 words
A paper product as defined in claim 1 wherein the urea-formaldehyde polymer has a BET specific surface area of 10 to 40 m2/g, an absorption capacity for aqueous starch solution of 4.7 to 7.0 gms/gm pigment and a mean agglomerate size of 5.5 to 9.0 microns.
Claim 6
Dependent Claim 57 words
A paper product as defined in claim 1 wherein the pigmentary filler is an insoluble, infusible, non-porous, particulate urea-formaldehyde polymer having a molar ratio of urea to formaldehyde of 1:1.5, a BET specific surface area of 28.1 m2/g, an absorption capacity for aqueous starch solution of 5.7 gms/gm pigment and a mean agglomerate size of 8.3 microns.
Claim 7
Dependent Claim 57 words
A paper product as defined in claim 1 wherein the pigmentary filler is an insoluble, infusible, non-porous, particulate urea-formaldehyde polymer having a molar ratio of urea to formaldehyde of 1:1.5, a BET specific surface area of 31.8 m2/g, an absorption capacity for aqueous starch solution of 5 gms/gm pigment and a mean agglomerate size of 7 microns.
Claim 8
Dependent Claim 57 words
A paper product as defined in claim 1 wherein the pigmentary filler is an insoluble, infusible, non-porous, particulate urea-formaldehyde polymer having a molar ratio of urea to formaldehyde of 1:1.5, a BET specific surface area of 23.2 m2/g, an absorption capacity for aqueous starch solution of 5.2 gms/gm pigment and a mean agglomerate size of 7 microns.
Claim 9
Dependent Claim 57 words
A paper product as defined in claim 1 wherein the pigmentary filler is an insoluble, infusible, non-porous, particulate urea-formaldehyde polymer having a molar ratio of urea to formaldehyde of 1:1.5, a BET specific surface area of 28.0 m2/g, an absorption capacity for aqueous starch solution of 6.7 gms/gm pigment and a mean agglomerate size of 6.9 microns.
Claim 10
Dependent Claim 33 words
A paper product as defined in claim 1 wherein the pigmentary filler is present in amounts ranging from about 0.5 to about 30 percent by weight based on the weight of dry pulp.
Claim 11
Dependent Claim 33 words
A paper product as defined in claim 1 wherein the pigmentary filler is present in amounts ranging from about 0.5 to about 15 percent by weight based on the weight of dry pulp.

References Cited (Backward Citations)

US3037903A Cited
US3006561A Cited
US3509098A Cited
US3428607A Cited
US3393161A Cited
US3553115A Cited
US3849378A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1978-09-29 1979-03-31 1979-09-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1982-09-29 1983-03-31 1983-09-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1986-09-29 1987-03-31 1987-09-30 $7700.00 Window Closed / Lapsed

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