Method and apparatus for spreading treating agent on moving web

Abstract

A method and apparatus for spreading a treating agent, for example, size or a coating onto a moving surface in the manufacture of the web-shaped folios or paper and paperboard and various sheet products in particular, includes feeding the treating agent into at least one feeding chamber and directing the agent from the feeding chamber onto the moving surface. Jets are formed from the treating agent by directing the agent through at least one nozzle plate comprising openings that are defined by the nozzle plate around the entire periphery, and the formed jets are applied directly onto the moving surface.

Description

technical field [0001] The present invention relates to a method for applying a treatment agent, such as surface paste, water, or a paint mixture, to a moving surface as an unsupported jet that spreads over the web being treated. onto the surface of the web, or spread onto a surface which in turn transfers the treatment to the surface of the web in order to alter the properties of the web. The invention can also be applied, for example, to the treatment of flat-shaped products instead of roll coaters or curtain coaters. [0002] The invention also relates to a device for carrying out the method. Background technique [0003] Currently, paper and paperboard are coated and treated in a variety of ways. Coating is often done in two phases, first the coating is spread onto the web and the final coating is made separately by using a coating knife, a rod or an air brush. There are also treatments available that provide the correct amount of treatment that is uniform enough with...

AI Technical Summary

Problems solved by technology

[0004] Most dispensing devices for treatments currently in use are large and complex devices

All these devices operate with limitations related to product quality, production rate and other factors, which is why they are only suitable for a limited range of products

When updating machines, it is difficult to install bulky equipment in place of old equipment, limiting the use of replacement units in the modernization process

One problem with the most commonly used applicator is that the device employs a large flood and multiple coats, causing a portion of the paint to return as backflow, either by the applicator or by the doctor blade to a tank and then by This tank pumps the paint to the applicator

Removing air is difficult and degassers are expensive

In the return cycle, the treatment agent can easily become dirty, or otherwise be contaminated, we must ensure that the treatment agent remains clean

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