CH198970A - Process for the production of paints. - Google Patents

Description

  

  Procedure for the creation of Laeken. The present invention relates to a process for producing paints, characterized in that formaldehyde condensation products of aminotriazines are used as the paint-forming substance.



       The varnishes obtained have the property of providing coatings which, on the one hand, become hard and insoluble in the heat and, on the other hand, are lightfast and free of their own color.



  The reaction between formaldehyde and aminotriazines, especially melamine, takes place in several stages. First, methylol compounds are formed, which are arbitrarily soluble in water and alcohol. If the condensation is continued, the next hydropillic, then hydrophobic, resins form.

         D # uroli heat treatment, the condensation products finally turn into hard, insoluble and non-meltable masses.



  The formaldehyde condensation products of 2.4.6-tri, am # ino-I.'3., 5-tria, zins have proven particularly suitable. However, formaldehyde condensate products of other amino triazines can also be used with advantage for the present purpose, e.g. 2,4-amino-1. 3-5-triazine (formoguanamine ) and Jergl.



  For conversion into paints, the condensation products are preferably in organic solvents such as. B. Ilhylalkoliol, ButylaJkoliol or glycerides of linoleic acid, dissolved. The condensation products can also be prepared in the presence of organic solvents. Ineliesem case arise directly solutions that zux manufacture of paints, z.

   B. nitrocellulose lacquers, can serve. However, aqueous solutions of the condensation products can also be used to manufacture the paints. The fo # rmal # dellycl-- condensation products of the aminotriazines can also be used in a mixture with other lacquer-forming substances or with conventional additives.

        <I>Example<B>1:</B> </I> <B> 12.6 </B> parts by weight <B> (0.1 </B> Moi) melamine are in <B> 75 </ B> Volume divide. <B> (0.8 </B> Mol) 32 percent by volume neutral formaldehyde dissolved in the water bath and leave for <B> 10 </B> minutes. This is followed by cooling, with flakes separating out as soon as they cool down. After two days, the crystal pulp is sucked off, washed thoroughly with alcohol and dried for five hours at <B> 60 ° C </B>.



  <B> 50 </B> parts by weight of the methylol compound of melamine thus obtained are added to <B> 80 </B> parts by volume of butyl alcohol and <B> 0.5 </B> parts by volume of concentrated hydrochloric acid and 1/4 Hour-e heated to the boil. The result is an almost clear solution, which is a ready-to-use lacquer and quickly dries in a thin layer in the heat to form a hard lacquer film and hardens.

   Such solutions in butyl alcohol can be added to nitrocellulose lacquers, for example. to give them hardness and fullness.



  <I> Example 2: </I> <B> 50 </B> parts by weight of nitrocellulose ("1/2" second wool ") are triked in a mixture of <B> 10 </B> parts by weight. syl phosphate, <B> 10 </B> parts by weight of butyl alcohol, 50 parts by weight of liquid ester and 40 parts by weight of toluene dissolved.

   <B> 100 </B> parts by weight of an alcoholic melamine resin solution are stirred into the very thick, paste-like solution obtained, which is obtained by heating <B> 126 </B> parts by weight of melamine <B> (1 </B> Mol) with <B> 360 </B> parts by volume of a 41.8 percent alcoholic formaldehyde solution <B> (5 </B> Mol),

     <B> 300 </B> parts by volume of alcohol and <B> 1 </B> part by volume of concentrated hydrochloric acid (0.01 mol) under reflux for 45 minutes and subsequent cooling of the solution. The aged white solution is diluted for use with a mixture of equal parts of toluene, 1, absolute alcohol and ethyl acetate.

    The paint obtained in this way dries, poured onto glass or metal, water-white and mirror-smooth and, cured at a slowly increasing temperature, the temperature finally being kept at 120 ° C for about 2 hours, paint films of very good water resistance and hardness.



  <I>Example<B>3:</B> </I> First, a resin solution is prepared as follows: <B> 6.3 </B> parts by weight melamine (1 mole), <B> 15 </B> Part by volume 41.8 percent alcoholic formaldehyde # d ('/. Mol), <B> 15 </B> part by volume absolute alcohol, <B> 0.1 </B> part by volume concentrated hydrochloric acid (' / 1 "" mole)

      and <B> 6 </B> Parts of the monoglyceride of linolenic acid are allowed to react together for 31/2 hours on the refluxing Waisserbath.



  The resulting somewhat cloudy, pale yellowish, oily liquid is diluted with a little benzene before it solidifies and a siccative is added to it. The varnish obtained in this way, when applied to a base, dries in the air after some time to form clear, double-sided, hard coatings that can no longer be scratched with the nail.

 

Claims (1)

PATENT CLAIM: Process for the production of varnishes, characterized in that a19 varnish-forming substance, formal dehydrogenation products of aminotriazines, is used. The Ixwke obtained have the property of delivering coatings that on the one hand become hard and insoluble in the heat and on the other hand are lightfast and free of their own color.