摘要:
Effective, titanium-free agents for activating metal surfaces prior to phosphating these surfaces with phosphating baths containing zinc ions can be made by reacting alkali metal phosphates with 1,1-diphosphonic acids and their alkali metal slats and/or poly(aldehydocarboxylic acids) and their alkali metal salts.
摘要:
Effective, titanium-free agents for activating metal surfaces prior to phosphating these surfaces with phosphating baths containing zinc ions can be made by reacting alkali metal phosphates with 1,1-diphosphonic acids and their alkali metal salts and/or poly(aldehydocarboxylic acids) and their alkali metal salts.
摘要:
Activation of metal surfaces prior to phosphating can be improved by using aqueous dispersions of polymeric titanium(IV) phosphates in which at least 95% by weight of the polymeric particles have a particle diameter of less than 200 nm. This low particle diameter is attained by adding a titanium(IV)-complexing agent before or during an otherwise conventional reaction between a titanium(IV) compound, acid or phosphate, and water. The complexing agent is used in an amount of less than the stoichiometric amount, based on the titanium(IV) content. The best complexing agents are poly(aldehydocarboxylic acids), 1,1-diphosphonic acids, and/or the alkali metal salts of these types of acids.
摘要:
A process is disclosed for phosphating metallic surfaces, particularly electrolytically or hot dipped galvanized steel strip surfaces, by dip or spray processing the metallic surfaces with acidic aqueous phosphating solutions, wherein the workpieces are cathodically treated at the same time with a direct current. The process is characterized by (a) the use of phosphating solutions that contain the following components: Zn.sup.+2 cations in a range from 0.1 to 5 g/l; PO.sub.4.sup.-3 anions in a range from 5 to 50 g/l; NO.sub.3.sup.- anions in a range from 0.1 to 50 g/l; as well as Ni.sup.+2 cations in a range from 0.1 to 5 g/l and/or Co.sup.+2 cations in a range from 0.1 to 5 g/l; (b) the observance of the following conditions: pH value of the phosphating solutions in a range from 1.5 to 4.5; temperature of the phosphating solutions in a range from 10.degree. to 80.degree. C.; duration of treatment in a range from 1 to 300 sec, (c) simultaneous cathodic treatment of the workpiece during phosphating with a direct current having a density in the range from 0.01 to 100 mA/cm.sup.2.
摘要:
The invention concerns a process for a passivating post-treatment of phosphated metal surfaces of iron, steel, galvanized steel, zinc, aluminum, and their alloys, in which the phosphated metal surfaces are brought into contact at temperatures in the range from 10.degree. to 60.degree. C. with chromium-free, acidic, silicate-containing aqueous solutions having a pH in the range of 2 to 5 and 0.5 to 50 g/l of SiO.sub.2 and 0.5 to 100 g/l of an acid.
摘要:
The invention relates to a process for phosphating galvanized steel surfaces, preferably electrolytically or hot-dip galvanized surfaces of steel strip, by treating them in a bath or spray with acidic aqueous phosphating solutions, wherein the workpieces are given a d.c. cathodic treatment at the same time. In the process, (a) the phosphating solutions contain Zn.sup.+2 cations in the range from 0.1 to 5 g/l, PO.sub.4.sup.-3 anions in the range from 5 to 50 g/l, NO.sub.3.sup.- anions in the range from 0.1 to 50 g/l, Mn.sup.+2 cations in the range from 0.1 to 5 g/l, and Cu.sup.+2 cations in the range from 0.001 to 1 g/l; (b) the following conditions are used: pH of the phosphating solution in the range from 1.5 to 4.5, temperature of the phosphating solution in the range from 10.degree. to 80.degree. C., treatment time in the range from 1 to 300 sec; and (c) the workpieces are also cathodically treated with a direct current with a density in the range from 0.01 to 100 mA/cm.sup.2 during phosphating.
摘要:
The formation of troublesome microfoams in aqueous lacquer and synthetic resin dispersions, particularly in gloss lacquers, is prevented by the addition of from 0.01 to 1.5% by weight of a silicone-free foam inhibitor mixture. These foam inhibitor mixtures contain (a) from 70 to 98% by weight of a liquid, branched C.sub.16 -C.sub.30 alcohol, (b) from 0.5 to 20% by weight of hard paraffin, and (c) from 0.05 to 5% by weight of hydrophobized finely divided silica, and, optionally, small quantities of other ingredients.
摘要:
The formation of troublesome microfoams in aqueous lacquer and synthetic resin dispersions, particularly in gloss lacquers, is prevented by the addition of from about 0.01 to about 1.5% by weight of a silicone-free foam inhibitor mixture. This mixture consists of (a) from about 70 to about 98% by weight of a mineral oil liquid at room temperature or a mixture of such mineral oil with a C.sub.16 -C.sub.30 branched alcohol of the following formulaR.sup.1 --CH.sub.2 --CH.sub.2 --CHR.sup.2 --CH.sub.2 --CH.sub.2 --CH.sub.2 OH (I)in which R.sup.1 and R.sup.2 are C.sub.4 -C.sub.16 alkyl radicals, (b) from about 0.2 to about 5% by weight of a microcrystalline wax, (c) from about 0.5 to about 20% by weight of hard paraffin, (d) from 0.05 to 5% by weight of hydrophobized finely divided silica, and (e) from 0 to about 10% by weight of a soft paraffin (M.p. 32.degree.-42.degree. C.). Component (a) preferably consists of a mixture of mineral oil and branched alcohol (I) in a ratio of from 50:1 to 1:1.