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

Chloride type trivalent chromium black chromium plating solution

A technology of trivalent chromium and chromium plating solution, applied in the field of electroplating chemistry, which can solve the problems of poor corrosion resistance, mildew spots, uneven color and other problems of the coating

Inactive Publication Date: 2013-02-06
NANJING DADI REFRIGERATION FOOD
View PDF5 Cites 3 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Trivalent chromium electroplating is one of the plating types developed into industrial applications in recent years, but the current trivalent chromium black chromium plating process is still immature, and the black trivalent chromium plating produced by electroplating has poor positioning and high current density areas. And the color of the low current density area is uneven, the corrosion resistance of the coating is poor, it is easy to turn yellow and mildew in the air

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

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0015] The present invention will be further described below.

[0016] A chloride-type trivalent chromium plating black chromium plating solution, add a certain amount of pure water into the electroplating tank, and heat it to 70-90°C, then add 50g / L potassium chloride and 120g / L sodium chloride and 90g / L of ammonium chloride, stirring to dissolve completely. Then add about 40g / L of chromium chloride, stir to dissolve completely, then turn on the filter to filter, and alternately electrolyze with high current and low current for more than 1 hour to remove impurities. Then add ferric chloride to make the iron ion content in the plating solution between 250-500ppm, continue to add 40g / L ammonium oxalate, 10g / L malic acid and 6ml / L formic acid, stir to dissolve completely, and finally add 1~ 10g / L ammonium thiocyanate.

[0017] Hull cell test, the test condition is 8A, 2min. As the concentration of iron ions increases from 250ppm to 500ppm, the displacement ability of the coat...

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

No PUM Login to View More

Abstract

The invention discloses a chloride type trivalent chromium black chromium plating solution which comprises the following components by weight: 30 to 70g / L of chromium trichloride, 150-320g / L of conducting salt, 20 to 70g / L of complexing agent, 2 to 10g / L of blackening agent, and 0.2 to 1g / L of surfactant, wherein the conducting salt is one of or a mixture of potassium chloride, sodium chloride, ammonia chloride, sodium sulfate and potassium sulfate; the complexing agent is one of or a mixture of ammonium oxalate, malic acid and formic acid; and the blackening agent is one of or a mixture of ferric chloride, potassium thiocyanate, ammonium thiocyanate and cobalt nitrate. According to the chloride type trivalent chromium black chromium plating solution, a trivalent black chromium plating layer with thickness being 0.2 to 0.5microns can be obtained, an appearance of the plating layer is uniform and bright black, and the colors of a high electric current density region and a low electric current density region are essentially identical; and the chloride type trivalent chromium black chromium plating solution does not yellow or change color even if being placed in air in a plum rain season, and the mildews can not be found.

Description

[0001] technical field [0002] The invention belongs to the technical field of electroplating chemistry, in particular to a trivalent chromium electroplating process. Background technique [0003] Trivalent chromium electroplating is one of the plating types developed into industrial applications in recent years, but the current trivalent chromium black chromium plating process is still immature, and the black trivalent chromium plating produced by electroplating has poor positioning and high current density areas. And the color of the low current density area is uneven, the corrosion resistance of the coating is poor, and it is easy to turn yellow and mildew in the air. Contents of the invention [0004] Purpose of the invention: In order to overcome the deficiencies in the prior art, the present invention provides a chloride-type trivalent chromium-plating black chromium plating solution. The obtained trivalent chromium coating has a uniform bright black appearance, and...

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): C25D3/06C25D3/08
Inventor 陈大弟
Owner NANJING DADI REFRIGERATION FOOD
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