US 12,076,874 B2
Shaving blade
Hyun Ju Lee, Seoul (KR); Kwang Choon Ryu, Seoul (KR); and Min Joo Park, Seoul (KR)
Assigned to Dorco Co., Ltd., Seoul (KR)
Filed by DORCO CO., LTD., Seoul (KR)
Filed on Apr. 21, 2023, as Appl. No. 18/305,250.
Application 18/305,250 is a continuation of application No. 16/987,298, filed on Aug. 6, 2020, granted, now 11,660,770.
Claims priority of application No. 10-2019-0121755 (KR), filed on Oct. 1, 2019.
Prior Publication US 2023/0249371 A1, Aug. 10, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. B26B 21/60 (2006.01); B26B 21/56 (2006.01)
CPC B26B 21/60 (2013.01) [B26B 21/56 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A shaving blade for cutting hair, comprising:
a substrate having a cutting edge, a substrate tips, and a plurality of coating layers laminated on the substrate;
wherein:
a first thickness of the substrate is defined as a thickness measured at a first distance that is 8 micrometers from the substrate tip along a central axis;
a second thickness of the substrate is defined as a thickness measured at a second distance that is 16 micrometers from the substrate tip along the central axis;
a third thickness of the substrate is defined as a thickness measured at a third distance that is 32 micrometers from the substrate tip along the central axis;
a first difference is defined as a difference between the second thickness and the first thickness;
a second difference is defined as a difference between the second distance and the first distance;
a third difference is defined as a difference between the third thickness and the second thickness;
a fourth difference is defined as a difference between the third distance and the second distance;
a first average increasing thickness is defined as a thickness measured by dividing the first difference by the second difference;
a second average increasing thickness is defined as a thickness measured by dividing the third difference by the fourth difference;
the first average increasing thickness is greater than the second average increasing thickness;
the plurality of coating layers include a first coating layer, a second coating layer, and a third coating layer, the plurality of coating layers contain one or more of chromium boride (CrB), chromium carbide (CrC), or Diamondlike carbon (DLC),
side surfaces of the cutting edge are convexly shaped in a region adjacent to the second distance, and
the second thickness of the substrate is in a range from 2.41 to 3.76 micrometers, and wherein an outer surface of the substrate from a distance of 32 micrometers from the substrate tip to a distance of 100 micrometers from the substrate tip is linear.