| (19) |
 |
|
(11) |
EP 0 277 728 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
17.08.1988 Bulletin 1988/33 |
| (43) |
Date of publication A2: |
|
10.08.1988 Bulletin 1988/32 |
| (22) |
Date of filing: 21.01.1988 |
|
|
| (84) |
Designated Contracting States: |
|
BE CH DE FR GB LI SE |
| (30) |
Priority: |
30.01.1987 US 8981
|
| (71) |
Applicant: CALGON CORPORATION |
|
() |
|
| (72) |
Inventors: |
|
- Schaper, Raymond J.
()
- Falcione, Ronald J.
()
|
|
| |
|
| (54) |
Drainage and retention aids for newsprint furnishes |
(57) A method for improving drainage and the retention of inorganic fillers, cellulosic
fines and/or pigments in the production of paper and paper-like products, especially
newsprint, by the use of polymeric drainage/retention aids prepared from 75 to 99.9%,
by weight, acrylamide and 25 to 0.1%, by weight, acryloyloxyethyl trimethyl ammonium
chloride.