| (19) |
 |
|
(11) |
EP 0 335 575 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
12.12.1990 Bulletin 1990/50 |
| (43) |
Date of publication A2: |
|
04.10.1989 Bulletin 1989/40 |
| (22) |
Date of filing: 22.03.1989 |
|
|
| (84) |
Designated Contracting States: |
|
AT BE CH DE ES FR GB IT LI NL SE |
| (30) |
Priority: |
28.03.1988 GB 8807444
27.06.1988 GB 8815219
|
| (71) |
Applicant: ALLIED COLLOIDS LIMITED |
|
Bradford,
West Yorkshire BD12 0JZ (GB) |
|
| (72) |
Inventor: |
|
- Langley, John Graham
Baildon
Shipley
West Yorkshire BD17 6TM (GB)
|
| (74) |
Representative: Lawrence, Peter Robin Broughton et al |
|
GILL JENNINGS & EVERY,
Broadgate House,
7 Eldon Street
London EC2M 7LH
London EC2M 7LH (GB) |
|
| |
|
| (54) |
Production of paper and paper board |
(57) Paper or paper board is made by providing an aqueous cellulosic suspension containing
a cationic polymer and then adding cationic starch or a high molecular weight synthetic
cationic polymer, subjecting the suspension to shear, and then adding inorganic material
selected from bentonite or colloidal silica. The process is of particular value when
the suspension is formed from a mechanically derived pulp and/or deinked pulp and
when the product is to be newsprint or board.