Method for removing foreign matter from surface of article

Abstract

The present invention relates to a method of removing foreign matter from a surface of an article, the method comprising the steps of: i) providing an article whose surface is at least partially covered by foreign matter; ii) contacting the article provided in step i) with a cleaning medium and a carrier medium to obtain a mixture comprising foreign matters dissolved and / or dispersed in the cleaning medium, the carrier medium and an article without foreign matters wherein the cleaning medium is an acid having a pKa of-10 to 7 and a minimum concentration of 1 wt%, and the cleaning medium is an acid having a pKa of-10 to 7 and a minimum concentration of 1 wt%; the density of the carrier medium is different from the density of the cleaning medium; iii) separating the mixture obtained in step ii) to obtain a multiphase emulsion comprising at least a first phase comprising a carrier medium and an article without foreign matter and a second phase comprising a cleaning medium and foreign matter dissolved and / or dispersed therein; iv) separating the phase obtained in step iii); and v) separating the article without foreign matter from the carrier medium. The invention further relates to a device for carrying out the process according to the invention.

Description

technical field [0001] The present invention relates to a method for removing foreign matter, such as ink, from the surface of an article and an apparatus for carrying out the method. Background technique [0002] Several methods of removing ink from plastic materials are known in the art. [0003] EP 2832459 A1 relates to a method for removing ink printed on plastic films, which method includes various physical / chemical treatments. The main steps of the method are: trimming the material, grinding, removing ink from the film, rinsing the film, recovering the cleaning solution, recovering the pigment and drying the film. By this method, ink-free plastic films can be obtained on the one hand, and pigments can be obtained on the other hand. [0004] WO 2012 / 151291 A2 relates to an apparatus and method for removing ink images from plastic substrates, in particular plastic containers such as cups. Deinking the article with a solvent capable of dissolving the ink image allows t...

AI Technical Summary

Problems solved by technology

The efficiency of the process for foreign matter removal is a direct result of the concentration of components used in the cleaning medium, deviations in the mixture can affect the efficiency of foreign matter removal

Furthermore, the complexity of the process increases when the solutions are intended to be reused in the process after cleaning due to the specific combination of components required

Furthermore, the cleaning media known from the prior art are very expensive and the process must be carried out at high temperatures

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