| Title of Invention | A PROCESS LFOR ENHANCING THE RESISTANCE TO DARKENING OF HOT DIP GALVANIZED SHEET, CHROMATING BATH AND RESULTED CHROMATED GALVANIZED SHEET THEREOF |
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| Abstract | The invention relates to a process for enhancing the resistance to darkening of hot dip galvanized sheet comprising the steps of chromatising the galvanized sheet in a chromating bath solution at 25degreeC-60degreeC having Cr+6 ion of 2.5 to 4.5 gm/I and Cr+3 ion of 2 to 4 gm//I, having PH of 1.65 wherein in the bath nitric acid is added drop by drop until PH of the lbath reaches 1.00 to 1.60; followed by addition of cobalt nitrate in the bath; chromating the galvanized sheet in the bath for 0.5-4 seconds and drying the sheet after chromating in forced hot air at 75degree-150degreeC. The invention also relates to a chromating bath solution for treatment of GA steel sheet and the chromatized GA sheet resulted thereof. |
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383-cal-2002-granted-abstract.pdf
383-cal-2002-granted-claims.pdf
383-cal-2002-granted-correspondence.pdf
383-cal-2002-granted-description (complete).pdf
383-cal-2002-granted-examination report.pdf
383-cal-2002-granted-form 1.pdf
383-cal-2002-granted-form 13.pdf
383-cal-2002-granted-form 18.pdf
383-cal-2002-granted-form 2.pdf
383-cal-2002-granted-form 3.pdf
383-cal-2002-granted-letter patent.pdf
383-cal-2002-granted-reply to examination report.pdf
383-cal-2002-granted-specification.pdf
| Patent Number | 221739 | ||||||||||||||||||
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| Indian Patent Application Number | 383/CAL/2002 | ||||||||||||||||||
| PG Journal Number | 27/2008 | ||||||||||||||||||
| Publication Date | 04-Jul-2008 | ||||||||||||||||||
| Grant Date | 03-Jul-2008 | ||||||||||||||||||
| Date of Filing | 24-Jun-2002 | ||||||||||||||||||
| Name of Patentee | SINGH, A.K. | ||||||||||||||||||
| Applicant Address | RESEARCH AND DEVELOPMENT DIVISION, THE TATA IRON AND STEEL COMPANY LIMITED, JAMSHEDPUR 831001 | ||||||||||||||||||
Inventors:
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| PCT International Classification Number | C 25 D 5/40 | ||||||||||||||||||
| PCT International Application Number | N/A | ||||||||||||||||||
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