Paper coating apparatus and method
US4396648A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 8, 1982 |
| Grant date | Aug 2, 1983 |
| Priority date | — |
| Expiry date | Feb 8, 2002 |
Classification
- Technology area (CPC D)Textiles; Paper
- CPC primaryD21H5/0015
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
Applicators for applying a film of coating material on a moving web of paper carried through an application zone include a chamber which receives coating material under pressure and directs the material through a narrow outlet orifice into the application zone, and a doctor blade which extends from a trailing side of the zone in contact with the web. The upper edge of a front wall of the chamber is closely spaced from the web to form, in conjunction with the pressurized coating material flowing from the orifice, a liquid seal at a forward end of the application zone, and seals are established at opposite side ends of the zone to allow development of a positive liquid pressure in the zone. In the various embodiments, rotating rolls located in the chamber, in the orifice, in the space between the upper edge of the front wall and the web and in both the space and the orifice serve to meter, homogenize and control the pressure of coating material in the application zone.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.