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US 10,593,452 B2Granted
Magnetic sheet and antenna device comprising same
AssigneeSkc Co., Ltd.
InventorsTae Kyoung Kim, Jong Hwi Park, Jin Cheol Kim, Jonghak Choi, Nah Young Kim, Hyun Gon Moon
Life of this patent
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Abstract
A magnetic sheet having improved acid/base-resistant properties, corrosion-resistance, and an excellent magnetic property at NFC, WPC, and MST frequencies, has little changes in weight and thickness even if the environment changes, for example, even after an etching treatment for patterning, or a reflow or soldering process which is performed for its application to a product.
Claims20
A magnetic sheet comprising a magnetic powder and a binder resin,
- wherein the magnetic sheet has a magnetic permeability of 100 to 300 based on an alternating current with a frequency of 3 MHz;
- a magnetic permeability of 80 to 270 based on an alternating current with a frequency of 6.78 MHz;
- a magnetic permeability of 60 to 250 based on an alternating current with a frequency of 13.56 MHz;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when subjected to heat-treatment twice, the heat-treatment being composed of heating from 30° C. to 240° C. at a constant rate for 200 seconds and then cooling from 240° C. to 130° C. at a constant rate for 100 seconds;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N hydrochloric acid solution for 30 minutes;
- and a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N sodium hydroxide solution for 30 minutes.
3 more elements
A conductive magnetic composite sheet comprising a magnetic sheet and a conductive foil disposed on at least one side of the magnetic sheet,
- wherein the magnetic sheet comprises a magnetic powder and a binder resin, and
- the magnetic sheet has a magnetic permeability of 100 to 300 based on an alternating current with a frequency of 3 MHz;
- a magnetic permeability of 80 to 270 based on an alternating current with a frequency of 6.78 MHz;
- a magnetic permeability of 60 to 250 based on an alternating current with a frequency of 13.56 MHz;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when subjected to heat-treatment twice, the heat-treatment being composed of heating from 30° C. to 240° C. at a constant rate for 200 seconds and then cooling from 240° C. to 130° C. at a constant rate for 100 seconds;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N hydrochloric acid solution for 30 minutes;
- and a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N sodium hydroxide solution for 30 minutes.
4 more elements
An antenna device comprising a magnetic sheet and an antenna pattern disposed on at least one side of the magnetic sheet,
- wherein the magnetic sheet comprises a magnetic powder and a binder resin, and
- the magnetic sheet has a magnetic permeability of 100 to 300 based on an alternating current with a frequency of 3 MHz;
- a magnetic permeability of 80 to 270 based on an alternating current with a frequency of 6.78 MHz;
- a magnetic permeability of 60 to 250 based on an alternating current with a frequency of 13.56 MHz;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when subjected to heat-treatment twice, the heat-treatment being composed of heating from 30° C. to 240° C. at a constant rate for 200 seconds and then cooling from 240° C. to 130° C. at a constant rate for 100 seconds;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N hydrochloric acid solution for 30 minutes;
- and a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N sodium hydroxide solution for 30 minutes.
4 more elements
A method of preparing an antenna device, the method comprising:
- bonding a magnetic sheet to a conductive foil by applying heat and pressure thereto;
- and
- etching the conductive foil to form an antenna pattern therein,
- wherein the magnetic sheet has a magnetic permeability of 100 to 300 based on an alternating current with a frequency of 3 MHz;
- a magnetic permeability of 80 to 270 based on an alternating current with a frequency of 6.78 MHz;
- a magnetic permeability of 60 to 250 based on an alternating current with a frequency of 13.56 MHz;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when subjected to heat-treatment twice, the heat-treatment being composed of heating from 30° C. to 240° C. at a constant rate for 200 seconds and then cooling from 240° C. to 130° C. at a constant rate for 100 seconds;
- a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N hydrochloric acid solution for 30 minutes;
- and a thickness change of 5% or less and a magnetic permeability change of 5% or less when immersed in a 2 N sodium hydroxide solution for 30 minutes.
6 more elements
Dependencies are inferred from the claim text.