CS226331B1 - Method of manufacturing lacquered polypropylene foils - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to a process for producing polypropylene lacquer films by applying dispersed synthetic macromolecular substances in a single layer on one or two sides in an amount of 15 to 70 g / m ² .

The prior art process for producing polypropylene lacquered films is based on the need to pre-coat (disrupt the surface) the coating prior to painting so that the applied aqueous dispersions based on polyvinylidene acrylic copolymers appear to adhere to the surface of the film. In addition, it is necessary to use dispersions of two kinds, the so-called primer with increased adhesion to the polypropylene film and a topcoat which achieves the necessary thickness of the ether on the polypropylene film.

The aforementioned drawbacks are eliminated by a process for the production of polypropylene lacquer films by applying synthetic macromolecular substances according to the invention, which is carried out by applying to the polypropylene film one or both sides of the dispersion in a quantity of 15 to 70 g / m ² dispersion. 99.5 wt. % of a tarpolymer in which 70 to 40 wt. % vinyl chloride, 30 to 60 wt. % vinyl acetate and 3 to 2 wt. % of one monomer selected from the group of alkyl acrylates, alkyl maleate and vinylidene chloride as comonomers, wherein the dispersion contains 0.5 to 8 wt.%, preferably 1 to 5 wt. % of aliphatic glycol ethers or esters and the solids content of the dispersion is 15 to 55 wt.

Application of aqueous dispersions! The polypropylene film is practically done by dipping a polypropylene film in a coating device into an aqueous dispersion of a macromolecular synthetic substance having a given dry matter content, from where the process is through a drying device, where water evaporates and a film of the macromolecular material of necessary depth is formed. The other side of the film is lacquered in the same manner after pre-overturning the polypropylene film with the unlabelled side to the film coating application device by dispersing the macromolecular material.

The advantage of the method according to the invention is mainly that the dispersions are applied to the untreated film as well as that the synthetic macromolecular substance dispersion is applied in only one layer, thus making it possible to achieve up to twice the production of lacquered polypropylene films on existing bilayer devices.

Last but not least, the production method of the present invention also results in energy savings in that the dispersion can be applied! even on raw film, which operation consumes not a small amount of energy.

Example 1

Composition dispersion: 9690 g of demi water, 238 g of ethylene glycol monoethyl ether, 306 g of merzolate (100%), 85 g of CH 2 COONa. 3 HgO, 17 g KgSgOg and 4080 g vinyl acetate, 6 120 g vinyl chloride as copolymer. The solids of said dispersion are treated with demi-water to a dry matter content of 26% by weight.

The dispersion thus treated is fed into a coating device for the coating of polypropylene films. The deposition conditions are adjusted such that the thickness of one layer of the dispersion applied to the film is 30 µm.

Example 2

An aqueous dispersion of composition: 9600 g of demi water, 476 g of ethylene glycol monoethyl ether, 306 g of merzolate (as 100%), 85 g of CH 2 COONa is charged to a coating device on a polypropylene film lacquer. 3 HgO, 18 g KgSgOg and 4080 g vinyl chloride, 6 120 g vinyl acetate, 357 g 2-ethylhexyl acrylate as terpolymer.

The dispersion dry matter is treated with demi-water to a dry matter content of 28% by weight. The deposition of the dispersion thus treated on the polypropylene film is controlled such that the thickness of one layer of the dispersion reached 35 µm.

Example 3

Dispersion of the following composition: 10 200 g demi water, 238 g ethyl glycol monobutyl ether,

272 g merzolate (as 100%), 85 g CH 2 COONa. 3 HgO, 17 g KgSgOg and 4080 g vinyl acetate,

120 g of vinyl chloride, 595 g of butyl acrylate as terpolymer, were used as a fill after adjusting the dry matter content to 40% by weight. to a coating device on a polypropylene film lacquer. The deposition is controlled so that the thickness of one layer of the dispersion is 25 µm.

Example 4

Composition dispersion: 8 500 g demi water, 238 g ethylene glycol monoethyl ether, 272 g merzolate (as 100%), 85 g CH COONa. 3 H 2 ^O , 17 g of ^K 2 ^S 2 ° e ^and 3 672 g of vinyl acetate, 5 508 g of vinyl chloride, 1020 g of vinylidene chloride as terpolymer are diluted with water to a dry matter content of 25.5% by weight. The dispersion thus treated is metered in the necessary amount into a coating device for the coating of polypropylene films. The deposition is controlled so that the thickness of one dispersion layer is 40 µm.

Example 5

Dispersion: 10 200 g demi water, 238 g ethylene glycol monoethyl ether acetate, 306 g merzolate (as 100%), 85 g CH 2 COONa. 3 H ₂ 0, 17 gi ^ S ^ Og and 3672 g of vinyl acetate, a 5 508 g vinyl chloride, 1 g of dibutyl maleate as 020 terpolymer to adjusting the dry matter content of demineralized water to 20% by weight. is used as a filler for a coating device for coating polypropylene films. The deposition is controlled so that the thickness of one layer of the dispersion is 55 µm.

After drying of the film, a given dispersion of 55 put thickness is applied to the non-lacquered side of the film. After drying, the total thickness of the two-side lacquered film is 40 puu.

Claims (2)

OBJECT OF THE INVENTION Method for producing polypropylene lacquered films by applying synthetic macromolecular substances, characterized in that a dispersion of 15 to 70 g / m ^{2 of} dispersion is applied in one layer on one side or both sides to the polypropylene film, the dry matter of the dispersion consisting of 92 to 99.5 # wt. % terpolymer in which 70 to 40 wt. % vinyl chloride, 30 to 60 wt. % vinyl acetate and 3 to 12 wt. one monomer selected from the group of alkyl acrylates, alkyl maleate, and vinylidene chloride as comonomers, wherein the dispersion contains 0.5 to 8 wt.%, preferably 1 to 5 wt. % of aliphatic glycol ethers or esters and the solids content in the dispersion is 15 to 55 wt. 2. The method according to claim 1, wherein the dispersion is applied to the untreated polypropylene film.