DE1050474B - Lacquers for rubber articles - Google Patents

Description

CO 9 D

GERMAN M & äk PATENT OFFICE

kl 22 h 3

INTERNAT. KL. C 09 f

EXPLAINING PAPER 1050 474

C 09 D 175 / 00- I

P 17600 IVc / 22 h

FILING DATE: DECEMBER 14, 1956

NOTIFICATION OF REGISTRATION ^J AND ISSUE OF

EDITORIAL: FEBRUARY 12, 1959

The invention relates to a lacquer based on isocyanate-modified polyesters for objects made of rubber.

With the versatile use of polyurethane plastics, this has also been introduced as a plastic coating. When used as a coating for rubber articles that have not been subjected to any pretreatment, however, a disadvantage has been found in that in many cases the coatings no longer adhere firmly and loosen again after prolonged use. Furthermore, it is already known to first crosslink polyester with a partial amount of polyisocyanates and to add further proportions of polyisocyanates to the paint produced shortly before application. These processed together with xylene-formaldehyde resins varnishes are "5 but virtually inelastic, so that an application as a rubber coating is virtually impossible (elasticity up to 5 ° / ₀ elongation versus elongation of about 100 ° / ₀ of the paints according to the invention).

Now a lacquer for coating rubber ao articles based on polyester-polyisocyanate combinations found, the polyester initially crosslinked with partial amounts of polyisocyanate and the paint shortly before the application, further proportions of polyisocyanates are added; What is new about the paint is that »5 it also contains ethereal polysulphides with terminal mercaptan groups. The one made in this way Lacquer also adheres very well to untreated natural or synthetic rubber objects. Even after a long time and strong dynamic stress, the paint coating is not damaged. The paint itself stands out also from the fact that it can be kept unchanged for a long time. To the adhesive strength even for unusual To ensure loads, it is advantageous to give the coated body a longer drying and baking time to subjugate. The good flowability of the lacquer for rubber articles

Applicant:

Phoenix Gummiwerke Aktiengesellschaft, Hamburg-Harburg, Hannoversche Str. 88

Dr. Hans Peters, Hamburg, has been named as the inventor

Lacquer leads to a smooth, shiny surface. the Simultaneous use of dyes is beneficial because the colors are effective due to the high transparency of the paint come for retribution. The combination of these properties leads to a number of new uses. Heavy-duty rubber objects, such as B. rubber suspension elements be coated with varnish in a simple and economical way in the immersion process. But also fashion and sporting goods can be because of the desired color with the same paint in an equally advantageous manner Undergo treatment.

Depending on the choice of the ethereal polysulphides mixed in, the varnish can be modified with respect to the ones mentioned Properties vary.

Example of a paint mixture

100 g isocyanate polyester (molecular weight 2000) made from polyester made from ethylene glycol and adipic acid and 25% naphthylene diisocyanate, 25 g of polysulfide of the formula

HS - (C ₂ H ₄ - C - CH ₂ - O - C ₂ H ₄ - S - S) _e - C ₂ H ₁ - O - CH ₂ - O - C ₂ - H ₄ - SH,

0.2 g of phthalocyanine dye, 300 g of ethyl acetate, 20 g of a 20% triphenylmethane triisocyanate solution in Methylene chloride.

The applied lacquer coating is subsequently annealed at 25 ° C and dried at 65 ⁰ C.

Claims (1)

Claim: Coating lacquers for rubber articles based on "Pblyester-Polyisocyanat-combinations, whereby cyanate cross-linked and further proportions of polyisocyanates have been added to the paint shortly before application, characterized in that they contain ether-like polysulfides with terminal mercaptan groups as a further additive contain.