Title:
PRE-TREATMENT LIQUID AND METHOD FOR MANUFACTURING ELECTROMAGNETIC STEEL SHEET PROVIDED WITH INSULATING FILM
Document Type and Number:
WIPO Patent Application WO/2023/139847
Kind Code:
A1
Abstract:
The present invention obtains an electromagnetic steel sheet that is provided with an insulating film having excellent insulation characteristics, that has an excellent appearance, and that provides a high tensile force but exhibits less iron loss. Provided is a pre-treatment liquid to be used on an electromagnetic steel sheet having a forsterite coating film on the surface before applying an insulating film treatment liquid containing phosphates. When the phosphate concentration of the pre-treatment liquid is defined as A mass% as expressed as H3PO4, the refractive index R of the pre-treatment liquid satisfies formula (1): 9.0×10-4×A+1.3340≤R.
Inventors:
TERASHIMA TAKASHI (JP)
KOKUFU KARIN (JP)
KOKUFU KARIN (JP)
Application Number:
PCT/JP2022/036059
Publication Date:
July 27, 2023
Filing Date:
September 28, 2022
Export Citation:
Assignee:
JFE STEEL CORP (JP)
International Classes:
C23C22/78; C21D9/46; C22C38/00; C22C38/60; C23C22/00; H01F1/147
Domestic Patent References:
| WO2018123339A1 | 2018-07-05 | |||
| WO2020036006A1 | 2020-02-20 |
Foreign References:
| JPH05311453A | 1993-11-22 | |||
| JP2020111815A | 2020-07-27 | |||
| JP2017532438A | 2017-11-02 |
Attorney, Agent or Firm:
ITOH Hideaki et al. (JP)
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