Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Chromium(vi)-free black passivation of surfaces containing zinc

A black, passivation layer technology, applied in the field of black conversion layer treatment solution, can solve the problem of black zinc alloy surface that cannot be successfully

Active Publication Date: 2010-03-10
ATOTECH DEUT GMBH
View PDF6 Cites 19 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

In the above-mentioned disclosed methods, there is a special defect that it is not possible to successfully obtain a black zinc alloy surface with good alkali corrosion resistance ("Grundkorrosionsschutz")

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Chromium(vi)-free black passivation of surfaces containing zinc
  • Chromium(vi)-free black passivation of surfaces containing zinc
  • Chromium(vi)-free black passivation of surfaces containing zinc

Examples

Experimental program
Comparison scheme
Effect test

example 1-6

[0076] An aqueous reaction solution having the composition shown in Table 1 was prepared (individual components were added in the same form as in Comparative Example 2). The pH of each solution was adjusted to the value shown in Table 1 with nitric acid and sodium hydroxide.

[0077] Steel structural elements are coated electrochemically with the zinc-containing alloys indicated under the respective headings in Table 1 and, after electrochemical coating, rinsed thoroughly with demineralized water and subsequently in 0.3% nitric acid at 20-30°C 10 seconds of activation followed by a full rinse. Next, the elements were immersed in the reaction solution under the conditions (temperature, treatment time) shown in Table 1. Subsequently, the surface coating ("Versiegelung") was carried out with Corrosil 501, which consists of an aqueous polymer dispersion with a silicate component. The results of a visual (color) evaluation and a salt spray test according to DIN 50021 SS before an...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
composition ratioaaaaaaaaaa
Login to View More

Abstract

Treatment solution contains first carboxylic acids with 1-8 carbon atoms and having no polar groups with the exception of the carboxyl group, second carboxylic acids with 1-8 carbon atoms having polargroups, 2-400 mmol / l chromium ions and 50-2000 mmol / l nitrate ions. The total concentration of carboxyl groups in the first carboxylic acids is 5-150 mmol / l. The total concentration of carboxyl groups in the second carboxylic acids is 5-150 mmol / l. The ratio of concentration of nitrate ions to chromium ions is at least 1. Independent claims are also included for the following: (1) Composition producing the above treatment solution by diluting with water; and (2) Method for the black passivation of zinc-containing surfaces using the treatment solution.

Description

technical field [0001] The present invention relates to a treatment solution and a method for producing a black conversion layer substantially free of chromium (VI) on the surface of a zinc-containing alloy. Background technique [0002] The use of conversion coatings to enhance the protective effect of cathodic protection corrosion protection systems and as a primer for paints and coatings has been known for a long time. Especially for substrates containing zinc, cadmium and aluminum, chromate passivation is used to treat the surface in addition to phosphating. [0003] Accordingly, the surface to be treated is placed in a treatment solution whose main component is chromium (VI) (or hexavalent chromium) compounds. The conversion layer thus obtained also contains chromium(VI) ions. Conversion layers generally have good corrosion protection and decorative properties. However, due to the toxicity of chromium (VI), the application of chromium (VI)-containing solutions and ch...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): C23C22/48C23C22/53B05D7/00B05D7/14C25D11/38
CPCC23C22/53C25D11/38C23C2222/10C23C22/48C23C22/34
Inventor 马斯罗娃·克罗左娃瓦茨拉夫·克里斯吉里·克罗别克比约恩·丁沃斯
Owner ATOTECH DEUT GMBH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com