Asymmetrical razor blades

Abstract

The present disclosure relates to a razor blade. According to one embodiment of the present disclosure, a razor blade is provided, comprising: a substrate including a substrate tip and a first face and a second face extending from the substrate tip; and a coating layered on the substrate and including a final tip, a first cutting face, and a second cutting face, wherein the first cutting face and the second cutting face extend from the final tip and correspond to the first face and the second face, respectively; the first cutting face includes a first tangent face extending from the final tip and a second tangent face extending from the first tangent face; the second cutting face includes a third tangent face extending from the final tip and corresponding to the first and second tangent faces; a first straight line connecting the first tangent face and a second straight line connecting the second tangent face are not parallel; the final tip deviates from a center line, and the center line passes through the substrate tip to bisect the substrate.

Description

Technical Field

[0001] The present disclosure relates to an asymmetrical shaving blade. Background Art

[0002] The contents recorded in this section are merely used to provide background information for the present invention and do not constitute prior art.

[0003] The shaving feel a user experiences during shaving can vary depending on the shape of the shaving blade. In particular, the shape of the substrate of the shaving blade has a significant impact on the cutting force of the shaving blade.

[0004] Generally, the thinner the substrate, the less cutting force the razor blade exerts, resulting in a more comfortable shave. However, if the substrate thickness falls below a predetermined value, the durability of the razor blade decreases. In other words, when designing the profile of a razor blade, there is a trade-off between a comfortable shave and the durability of the razor blade.

[0005] In this regard, it can be said that the area close to the tip of the razor blade has a greater correlation with the durability of the razor blade, and the area far from the tip of the razor blade has a higher correlation with the cutting force of the razor blade.

[0006] US Patent No. 10549438 (hereinafter referred to as Patent Document 1), which is a conventional razor blade, discloses a razor blade having a profile with two facets in consideration of these relationships.

[0007] Specifically, the razor blade of Patent Document 1 includes a pair of first facets extending from the tip of the razor blade and a pair of second facets extending from each first facet. Moreover, the first facets and the second facets are wedge-shaped, and the pair of first facets form a wide facet angle.

[0008] Thus, the razor blade of patent document 1 can have a relatively wide area near the tip and a relatively narrow area in the area away from the tip. Therefore, the razor blade of patent document 1 can provide a comfortable shaving feeling while having greater durability.

[0009] Furthermore, the razor blade is slightly flat against the skin surface during shaving, and is moved in the shaving direction. The cutting edge of the razor blade is divided into a non-facing edge located forward in the shaving direction and a facing edge located backward in the shaving direction. At least a portion of the facing edge is in direct contact with the user's skin during shaving.

[0010] The contact between the razor blade and the user's skin can directly affect the shaving sensation and the durability of the razor blade. From this viewpoint, the face side edge adjacent to the user's skin has a greater impact on the shaving sensation and the durability of the razor blade than the non-face side edge.

[0011] Therefore, when designing the profile of a razor blade, the non-face side edge and the face side edge should be designed to be different according to the characteristics of each edge.

[0012] But, existing razor blade including patent document 1 generally has the cutting edge of symmetrical shape, and does not distinguish non-face side edge and face side edge.That is, existing most of razor blades do not fully consider the characteristic of non-face side edge and face side edge. Summary of the Invention

[0013]

Technical Issues

[0014] In view of the above, an object of the present disclosure is to provide an asymmetrical razor blade shape capable of improving the durability of the razor blade and reducing the cutting force of the razor blade.

[0015]

Technical solution

[0016] According to one embodiment of the present disclosure, a razor blade is provided, comprising: a substrate including a substrate tip and a first face and a second face extending from the substrate tip; and a coating, which is a coating stacked on the substrate and includes a final tip, a first cutting face, and a second cutting face, the first cutting face and the second cutting face extending from the final tip and corresponding to the first face and the second face, respectively; the first cutting face including a first tangent face extending from the final tip and a second tangent face extending from the first tangent face; the second cutting face including a third tangent face extending from the final tip and corresponding to the first tangent face and the second tangent face; a first straight line connected to the first tangent face and a second straight line connected to the second tangent face are not parallel; the final tip deviates from a central line, and the central line passes through the tip of the substrate so as to divide the substrate in two.

[0017] Beneficial effects

[0018] According to the present embodiment as described above, since the asymmetrical cutting edges have different shapes from each other, there is an effect of providing a razor blade capable of improving durability and reducing cutting force. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figures 1 to 3 is a simplified schematic diagram of an area near the final tip of a razor blade according to an embodiment of the present disclosure.

[0020] Figure 4 yes Figure 3 An enlarged view of the intersection of some of the straight lines.

[0021] Figure 5 is a simplified schematic diagram of a razor blade according to an embodiment of the present disclosure.

[0022] Figure 6 FIG. 1 is an exemplary diagram of shaving using a razor including a razor blade according to an embodiment of the present disclosure.

[0023] Figure 7 FIG2 is an exemplary diagram of a razor blade used for a double-sided blade according to an embodiment of the present disclosure.

[0024] Figure 8 FIG. 1 is a simplified schematic diagram of a razor blade according to a modified embodiment of the present disclosure.

[0025] Figure 9 is a simplified schematic diagram of an area near the final tip of a razor blade according to another embodiment of the present disclosure. DETAILED DESCRIPTION

[0026] Below, some embodiments of the present disclosure are described in detail with reference to the accompanying drawings. When assigning reference numerals to components in the drawings, identical components will be assigned the same reference numerals whenever possible, even when they are referenced in other drawings. Furthermore, during the description of the present disclosure, if a detailed description of a related known structure or function is deemed to obscure the main purpose of the present disclosure, such detailed description will be omitted.

[0027] When describing components involved in the embodiments of the present disclosure, symbols such as first, second, i), ii), a), and b) may be used. These symbols are used solely to distinguish a component from other components and do not limit the nature, order, or sequence of the corresponding components. When a description states that a part "includes" or "has" a component, unless otherwise stated, it indicates that other components are further included, not excluded.

[0028] Figures 1 to 3 is a simplified schematic diagram of an area near the final tip of a razor blade according to an embodiment of the present disclosure.

[0029] Reference Figure 1 A shaving blade (10) may include a substrate (110) and a coating (120) stacked on the substrate (110).

[0030] The substrate (110) may include a substrate tip (112), a first surface (114), and a second surface (116).

[0031] The first face (114) and the second face (116) may extend from the substrate tip (112) and be substantially symmetrical with respect to a central line (CL) that passes through the substrate tip (112) and divides the substrate (110) in two.

[0032] At this time, in order to realize the shape of the asymmetric cutting surfaces (123, 126), the coating layer formed on the first surface (114) and the coating layer (120) formed on the second surface (116) may have different thicknesses or different shapes.

[0033] However, the present disclosure is not limited thereto, and the first surface (114) and the second surface (116) may also be asymmetrical. In this case, the shape of the first surface (114) may correspond to the shape of the first cutting surface (123), and the shape of the second surface (116) may correspond to the shape of the second cutting surface (126).

[0034] The substrate (110) may include at least one of stainless steel, carbon steel, and ceramics. However, the present disclosure is not limited thereto, and the substrate (110) may also include other materials.

[0035] The coating (120) may include an ultimate tip (122), a first cutting surface (123), and a second cutting surface (126).

[0036] A first cutting face (123) and a second cutting face (126) may extend from the final tip (122).

[0037] The first cutting surface (123) may correspond to the first surface (114) of the substrate (110) and be arranged adjacent to the first surface (114). The second cutting surface (126) may correspond to the second surface (116) of the substrate (110) and be arranged adjacent to the second surface (116).

[0038] The first cutting face (123) may include a first facet (124) extending from the final tip (122) and a second facet (125) extending from the first facet (124).

[0039] A first line (L1) connected to the first cutting surface (124) and a second line (L2) connected to the second cutting surface (125) may not be parallel. In other words, the first cutting surface (123) may have a wedge shape at the connection between the first cutting surface (124) and the second cutting surface (125).

[0040] At this time, the angle between the first straight line (L1) and the second straight line (L2), that is, the wedge angle (WA), can be 100 to 160 degrees, preferably 110 to 140 degrees. The above numerical range is only an example, and the present disclosure is not limited thereto.

[0041] The first cutting surface (123) has a wedge shape, so that the thickness of the razor blade (10) in an area close to the final tip (122) is relatively thicker, and the thickness of the razor blade (10) in an area away from the final tip (122) is relatively thinner.

[0042] The area of ​​the razor blade (10) near the final tip (122) has a greater correlation with the durability of the razor blade (10), and the area of ​​the razor blade (10) away from the final tip (122) has a greater correlation with the cutting force of the razor blade (10).

[0043] Therefore, by forming a wedge shape on the first cutting surface (123), the razor blade (10) according to an embodiment of the present disclosure can improve durability while reducing cutting force.

[0044] The second cutting face (126) may include a third facet (127) extending from the final tip (122).

[0045] The third cut surface (127) may correspond to the first cut surface (124) and the second cut surface (125). That is, the third cut surface (127) may face the first cut surface (124) and the second cut surface (125).

[0046] Unlike the wedge-shaped first cutting surface (123), the third cutting surface (127) of the second cutting surface (126) has a substantially flat profile. Therefore, the first cutting surface (123) and the second cutting surface (126) may have asymmetrical shapes.

[0047] In addition, one of the first cutting surface (123) and the second cutting surface (126) is a non-facing edge, and the other of the first cutting surface (123) and the second cutting surface (126) can be a facing edge. Therefore, the razor blade (10) according to an embodiment of the present disclosure can have an asymmetric shape between the non-facing edge and the facing edge.

[0048] The tip (122) eventually deviates from the center line (CL), and the center line (CL) passes through the substrate tip (112) to divide the substrate (110) in two.

[0049] For example, the final tip (122) can be deviated toward the second surface (116) based on the center line (CL). In this case, the thickness of the coating (120) used to form the second cutting surface (126) can be relatively thicker, thereby improving the durability of the second cutting surface (126).

[0050] However, the present disclosure is not limited thereto. For example, the final tip (122) may also be located on the center line (CL) or biased toward the first surface (114) with respect to the center line (CL).

[0051] When the final tip (122) is biased toward the first surface (114) based on the center line (CL), the thickness of the coating (120) used to form the first cutting surface (123) will be relatively thicker, thereby improving the durability of the first cutting surface (123).

[0052] The angle between the first line (L1) and the third line (L3) connected to the third section (127), i.e., the tip angle (TA), can be 55 to 130 degrees, preferably 55 to 100 degrees, and more preferably 60 to 90 degrees. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0053] In addition, the tip angle (TA) defined in the area near the final tip (122) of the razor blade (10) has a great correlation with the durability of the razor blade (10). For example, the larger the tip angle (TA), the better the durability of the razor blade (10).

[0054] Therefore, the razor blade (10) according to an embodiment of the present disclosure has a larger tip angle (TA), thereby further improving the durability of the razor blade (10).

[0055] A third angle (A3) between the first line (L1) and the center line (CL) is different from a fourth angle (A4) between the third line (L3) and the center line (CL). For example, the third angle (A3) may be greater than the fourth angle (A4).

[0056] in addition, Figure 1 The enlarged view of FIG. 1 shows an angle (A3') between a perpendicular line (PL) and a first straight line (L1), and an angle (A4') between the perpendicular line (PL) and a third straight line (L3), wherein the perpendicular line (PL) is defined as a straight line passing through the final tip (122) and parallel to the center line (CL).

[0057] Since the vertical line (PL) is parallel to the central line (CL), the value of the third angle (A3) between the first straight line (L1) and the central line (CL) may be equal to the value of the angle (A3') between the first straight line (L1) and the vertical line (PL), and the value of the fourth angle (A4) between the third straight line (L3) and the central line (CL) may be equal to the value of the angle (A4') between the third straight line (L3) and the vertical line (PL).

[0058] Therefore, as shown by the third angle (A3) and the fourth angle (A4), the angle (A3') between the vertical line (PL) and the first straight line (L1) may be different from the angle (A4') between the vertical line (PL) and the third straight line (L3). For example, the angle (A3') between the vertical line (PL) and the first straight line (L1) may be greater than the angle (A4') between the vertical line (PL) and the third straight line (L3).

[0059] When the angle (A3') between the vertical line (PL) and the first straight line (L1) is different from the angle (A4') between the vertical line (PL) and the third straight line (L3), the first cutting surface (123) and the second cutting surface (126) have an asymmetric shape with respect to the vertical line (PL).

[0060] In other words, when the third angle (A3) and the fourth angle (A4) are different, the first cutting surface (123) and the second cutting surface (126) may have an asymmetric shape with respect to the vertical line (PL). Figure 1 Although the third angle (A3) is shown as being greater than the fourth angle (A4), the present disclosure is not limited thereto. For example, the third angle (A3) may be smaller than the fourth angle (A4), or the third angle (A3) and the fourth angle (A4) may be the same. In this case, the first cutting surface (123) and the second cutting surface (126) may have an asymmetrical shape with respect to the vertical line (PL).

[0061] To enhance the durability of the razor blade (10), the coating layer (120) may include a hard coating layer. For example, the hard coating layer of the coating layer (120) may include at least one of DLC (diamond like carbon), Cr, Pt, CrB, and CrC. However, the present disclosure is not limited thereto, and the hard coating layer of the coating layer (120) may also include other materials.

[0062] In order to reduce the friction of the razor blade (10), the coating (120) may include a soft coating layer. For example, the soft coating layer of the coating (120) may include PTFE (Polytetrafluoroethylene). However, the present disclosure is not limited thereto, and the soft coating layer of the coating (120) may also include materials other than PTF.

[0063] The coating layer (120) may further include an overcoat layer disposed between the hard coating layer and the soft coating layer, and an adhesive layer disposed between the substrate (110) and the hard coating layer.

[0064] Reference Figure 2 , at a position separated by a predetermined distance from the substrate tip (112), a first thickness (first thickness, a) between the first surface (114) and the first cutting surface (123) may be relatively smaller than a second thickness (second thickness, b) between the second surface (116) and the second cutting surface (126).

[0065] Specifically, the value of the first thickness (a) divided by the second thickness (b) may be 0.1 to 2.5, preferably 0.2 to 2.0, and more preferably 0.25 to 1.0. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0066] By forming the second thickness (b) to be greater than the first thickness (a), the thickness of the coating (120) used to form the second cutting surface (126) can be made relatively thicker, thereby improving the durability of the second cutting surface (126).

[0067] The first distance (D1) between the vertical line (PL) and the central line (CL) may be 20 nm to 300 nm, preferably 30 nm to 250 nm, and more preferably 35 nm to 170 nm. The above numerical ranges are merely examples, and the present disclosure is not limited thereto.

[0068] The larger the value of the first distance (D1), the thicker the thickness of the coating (120) used to form the second cutting surface (126) is.

[0069] The second distance (D2) between the first horizontal line (H1) and the final tip (122) may be 50 nm to 400 nm, preferably 50 nm to 300 nm, and more preferably 50 nm to 200 nm. The above numerical ranges are merely examples, and the present disclosure is not limited thereto.

[0070] The first horizontal line (H1) is defined as a straight line passing through a first point (P1) and perpendicular to the center line (CL), and the first point (P1) is defined as a position where the first straight line (L1) and the second straight line (L2) intersect.

[0071] The third distance (D3) between the substrate tip (112) and the final tip (122) may be 100 nm to 600 nm, preferably 100 nm to 400 nm, and more preferably 100 nm to 300 nm. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0072] The fourth distance (D4) between the first position (P1) and the substrate tip (112) may be 100 nm to 400 nm, preferably 100 nm to 250 nm. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0073] Reference Figure 3 The fifth distance (D5) between the first position (P1) and the final tip (122) may be 100 nm to 600 nm, preferably 100 nm to 400 nm, and more preferably 100 nm to 250 nm. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0074] A sixth distance (D6) between the first point (P1) and the second point (P2) is 150 nm to 700 nm, preferably 150 nm to 400 nm, and more preferably 150 nm to 300 nm. The above numerical ranges are merely examples, and the present disclosure is not limited thereto. The second point (P2) is defined as the intersection of the first horizontal line (H1) and the third section (127).

[0075] The seventh distance (D7) between the first horizontal line (H1) and the second horizontal line (H2) can be 20 nm to 350 nm, preferably 20 nm to 250 nm, and more preferably 20 nm to 150 nm. The above numerical ranges are merely examples, and the present disclosure is not limited thereto. The second horizontal line (H2) is defined as a straight line passing through the substrate tip (112) and parallel to the first horizontal line (H1).

[0076] Figure 4 yes Figure 3 An enlarged view of the intersection of some of the straight lines.

[0077] Specifically, Figure 4 (a) shows the intersection of the second straight line (L2) and the third straight line (L3), Figure 4 (b) illustrates the intersection of the third straight line (L3) and the fourth straight line (L4).

[0078] Reference Figure 3 and Figure 4 The value of the tip angle (TA) divided by the first angle (A1) between the second straight line (L2) and the third straight line (L3) can be 1.5 to 3.5. The above numerical range is only an example, and the present disclosure is not limited thereto.

[0079] The angle between the third line (L3) and the fourth line (L4) connected to the second surface (116), i.e., the second angle (A2), can be 10 to 40 degrees, preferably 15 to 30 degrees. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0080] Figure 5 It is a simple schematic diagram of a razor blade (10) according to an embodiment of the present disclosure.

[0081] Reference Figure 5 The first cutting face (123) may include a fourth facet (128) extending from the second cutting facet (125), and the second cutting facet (126) may include a fifth facet (129) extending from the third cutting facet (127).

[0082] The fourth section (128) and the fifth section (129) may have symmetrical shapes.

[0083] In addition, the eighth distance (D8) between the third horizontal line (H3) and the final tip (122) may be less than 10 micrometers, preferably less than 5 micrometers. The above numerical ranges are only examples, and the present disclosure is not limited thereto.

[0084] Among them, the third horizontal line (H3) is defined as a straight line passing through the third position (third point, P3) and perpendicular to the central line (CL), and the third position (P3) is defined as the position where the third straight line (L3) intersects the sixth straight line (sixth line, L6) connected to the fifth section (129).

[0085] Since the fourth cutting surface (128) and the fifth cutting surface (129) have symmetrical shapes, based on the third position (P3), the area of ​​the second cutting surface (126) before the third position (P3) may be asymmetrical to the first cutting surface (123) corresponding thereto. On the contrary, the area of ​​the second cutting surface (126) after the third position (P3) is symmetrical to the area of ​​the first cutting surface (123) corresponding thereto.

[0086] In other words, in the area within the eighth distance (D8) from the final tip (122), the first cutting surface (123) and the second cutting surface (126) can be asymmetric, and in the area outside the eighth distance (D8) from the final tip (122), the first cutting surface (123) and the second cutting surface (126) can be symmetric.

[0087] Therefore, the razor blade (10) according to an embodiment of the present disclosure sets the area from the final tip (122) to the eighth distance (D8) to be asymmetric, thereby having a differentiated effect compared with the existing razor blades.

[0088] in addition, Figure 5 , the fourth point (fourth point, P4) defined as the position where the fifth line (fifth line, L5) connected to the fourth section (128) intersects the second line (L2) is illustrated as being located on the third horizontal line (H3), but the present disclosure is not limited thereto.

[0089] For example, the fourth position (P4) may also be located in an area within the eighth distance (D8) from the final tip (122) or in an area outside the eighth distance (D8) from the final tip (122).

[0090] also, Figure 5 Although the second cut surface ( 125 ) and the fourth cut surface ( 128 ) are shown to form a wedge shape and the third cut surface ( 127 ) and the fifth cut surface ( 129 ) are shown to form a wedge shape, the present disclosure is not limited thereto.

[0091] For example, the second and fourth cut surfaces 125 and 128 as well as the third and fifth cut surfaces 127 and 129 may not be wedge-shaped but may be smoothly connected.

[0092] Figure 6 This is an example diagram of shaving using a razor (6) including a razor blade (10) according to an embodiment of the present disclosure.

[0093] Specifically, Figure 6 (a) shows a razor blade (10) in which the first cutting surface (123) is a facial side edge. Figure 6 (b) illustrates a razor blade (10) in which the second cutting surface (126) is a facial side edge.

[0094] Reference Figure 6 (a) and Figure 6 (b) The razor (6) may include a razor cartridge (62) and a razor handle (64) extending from the razor cartridge (62).

[0095] The razor blade cartridge (62) is connected to or integrally formed with the razor handle (64).

[0096] The interior of the razor cartridge (62) can accommodate at least one razor blade (10).

[0097] The razor blade (10) may be a bended blade or a welded blade, but the present disclosure is not limited thereto. For example, the razor blade (10) may be a straight blade.

[0098] Reference Figure 6 (a) At least a portion of the first cutting surface (123) serving as a facial side edge can be brought close to the user's skin (C) during shaving.

[0099] Furthermore, the first cutting surface (123) has a wedge shape between the first cutting surface (124) and the second cutting surface (125), and the wedge shape can form a convex area on the first cutting surface (123).

[0100] Therefore, when the razor blade (10) is close to the skin (C) and almost in contact with the skin (C), the first cutting surface (123) will contact the skin (C) in more areas.

[0101] At this time, the tendency of the tip (122) to contact the skin (C) is reduced, so that the razor blade (10) can provide a comfortable shaving feeling without causing scars, scratches, or cuts on the skin.

[0102] Reference Figure 6 (b) At least a portion of the second cutting surface (126) serving as the facial side edge is close to the user's skin during shaving (C).

[0103] Furthermore, the second cutting surface (126) may have a flat profile, so that when the razor blade (10) is close to the skin (C) and almost in contact with the skin (C), the second cutting surface (126) contacts the skin (C) in a smaller area.

[0104] At this time, the final tip (122) can be closer to the lower area of ​​the body hair adjacent to the skin (C), whereby the body hair cut by the razor blade (10) can have a shorter length. Therefore, the razor blade (10) can shave more cleanly.

[0105] Figure 7 This is an exemplary diagram of a razor blade (10) used for a double-sided blade (72) according to an embodiment of the present disclosure.

[0106] Specifically, Figure 7 (a) shows a double-sided blade (72), Figure 7 (b) illustrates a shaving apparatus (7) comprising a double-sided blade (72).

[0107] Reference Figure 7 (a) A double edge blade (72) may include a blade body (722) and a first razor blade 10A and a second razor blade 10B formed on the blade body (722).

[0108] At least one of the first razor blade (10A) and the second razor blade (10B) is a razor blade (10) according to an embodiment of the present disclosure, and may have asymmetric cutting surfaces (123, 126). For example, based on the first razor blade (10A), a second cutting surface (126) may be formed on one side surface (721) of the two-sided blade (72), and a first cutting surface (123) may be formed on the other side surface (723) of the two-sided blade (72).

[0109] The first razor blade (10A) and the second razor blade (10B) may both include asymmetric cutting surfaces (123, 126) according to an embodiment of the present disclosure, but the present disclosure is not limited thereto. Therefore, one of the first razor blade (10A) and the second razor blade (10B) may also have an asymmetric cutting surface, and the other may have a symmetric cutting surface.

[0110] In addition, when the first razor blade (10A) and the second razor blade (10B) both include asymmetric cutting surfaces (123, 126), the first razor blade (10A) and the second razor blade (10B) can form the same type of cutting surface on the same side of the double-sided blade (72).

[0111] For example, the first razor blade (10A) and the second razor blade (10B) may have a second cutting surface (126) on one side (721) of the double-sided blade (72), and may have a first cutting surface (123) on the other side (723) of the double-sided blade (72).

[0112] However, the present disclosure is not limited thereto, and the first razor blade (10A) and the second razor blade (10B) may also have different types of cutting surfaces on the same surface of the double-sided blade (72).

[0113] The double-sided blade (72) can be broken into a plurality of slices by a breaking line (726). For example, the double-sided blade (72) can be broken into two slices so that each slice has a razor blade (10A, 10B). However, the present disclosure is not limited thereto, and the double-sided blade (72) can also be broken into three or more slices or not broken.

[0114] One of the multiple slices of the two-sided blade (72) can be installed in the blade holder (74) for use, but the present disclosure is not limited to this. For example, the two-sided blade (72) can also be configured to be directly installed on the blade holder (74) in an unbroken state.

[0115] Figure 7 (a) Although the diagram shows a double-sided blade (72) having two razor blades (10A, 10B), the present disclosure is not limited thereto. For example, the double-sided blade (72) may also include only one razor blade (10) having an asymmetric cutting surface (123, 126).

[0116] Reference Figure 7 (b) The shaving apparatus (7) may include a double-sided blade (72) and a blade holder (74).

[0117] The blade holder (74) may include a mounting portion (742) for mounting the double-sided blade (72) and a grip portion (744) for providing a gripping space for a user.

[0118] The mounting portion (742) can accommodate at least a portion of the double-sided blade (72) through an opening (E). The razor blade (10A) region of the double-sided blade (72) can be exposed to the outside through the opening (E).

[0119] Figure 7 (b) Although the mounting portion (742) is shown to have one opening (E) and the cut pieces of the double-sided blade (72) are accommodated in the opening (E), the present disclosure is not limited thereto.

[0120] For example, the mounting portion (742) may further include two openings (E) or the double-sided blade (72) may be mounted directly on the mounting portion (742) without being broken. When the non-broken double-sided blade (72) is mounted on the mounting portion (742) having two openings (E), the two razor blades (10A, 10B) are exposed to the outside through the respective openings (E).

[0121] The two-sided blade (72) can be installed in the mounting portion (742) and is replaceable. At this time, when the two-sided blade (72) is installed on the mounting portion (742), the directions of one side (721) and the other side (723) of the two-sided blade (72) can be opposite.

[0122] For example, the Figure 7 When the double-sided blade (72) is mounted on the mounting portion (742) in the direction shown in (b), the first cutting surface (123) of the first razor blade (10A) can be a facial side edge. Figure 7 When the double-sided blade (72) is mounted on the mounting portion (742) in the opposite direction to the direction shown in (b), the second cutting surface (126) of the first razor blade (10A) can become a facial side edge.

[0123] The razor blade (10) can have different characteristics depending on which of the first cutting surface (123) and the second cutting surface (126) is the facial side edge. Therefore, the user can set the direction of one side (721) and the other side (723) of the double-sided blade (72) to be different according to his own needs, and then install the double-sided blade (72) or even the slice of the double-sided blade (72) on the installation part (742) to shave.

[0124] Figure 7 (b) Although the diagram shows a situation where the double-sided blade (72) is installed in the blade holder (74), the present disclosure is not limited thereto. For example, the double-sided blade (72) can also be used alone without other devices such as the blade holder (74).

[0125] Figure 8 FIG. 1 is a simplified schematic diagram of a razor blade according to a modified embodiment of the present disclosure.

[0126] Reference Figure 8(a), a first thickness (a) between the first face (114A) and the first cutting face (123A) may have a value greater than a second thickness (b) between the second face (116A) and the second cutting face (126A).

[0127] By forming the first thickness (a) to be greater than the second thickness (b), the thickness of the coating (120) used to form the first cutting surface (123) can be made relatively thicker, thereby improving the durability of the first cutting surface (123).

[0128] Reference Figure 8 (b), the final tip (122B) may be located on the center line (CL). In this case, the final tip (122B) and the substrate tip (112B) may be arranged on the same line.

[0129] During shaving, the pressure applied by the razor blade can be transmitted to the final tip (122B) through the base tip (112B), and finally transmitted to the user's skin through the final tip (122B). When the base tip (112B) and the final tip (122B) are located on the center line (CL), in a state where the applied pressure is not eliminated by the torque, all the applied pressure transmitted from the base tip (112B) to the final tip (122B) can be used to cut body hair, so shaving can be performed with less force.

[0130] When the final tip (122B) is located on the center line (CL), the first thickness (a) between the first cutting surface (123B) and the first surface (114B) is generally constant, and the second thickness (b) between the second cutting surface (126B) and the second surface (116B) decreases the closer to the substrate tip (122B). Therefore, the closer to the substrate tip (122B), the greater the durability of the first cutting surface (123B) is, compared to the durability of the second cutting surface (126B). However, the present disclosure is not limited to this, and the first thickness (a) and the second thickness (b) can be pre-set to different values ​​according to the design of the razor blade.

[0131] For example, when the final tip (122B) is located on the center line (CL), at least one of the first thickness (a) and the second thickness (b) may become smaller or larger as it approaches the substrate tip (122B), or the first thickness (a) and the second thickness (b) may both have substantially certain values.

[0132] also, Figure 8 (b) Although the second thickness (b) is shown as having a relatively larger value than the first thickness (a), the present disclosure is not limited thereto. For example, the first thickness (a) may have a relatively larger value than the second thickness (b), or the first thickness (a) and the second thickness (b) may have substantially similar values.

[0133] Reference Figure 8 (c) Finally, the tip (122C) can be deflected toward the first surface (114C) based on the center line (CL).

[0134] When the final tip (122C) is deflected toward the first surface (114C) with respect to the center line (CL), the first thickness (a) between the first cutting surface (123C) and the first surface (114C) can generally have a certain value, and the second thickness (b) between the second cutting surface (126C) and the second surface (116C) decreases as it approaches the substrate tip (122C). Therefore, the closer to the substrate tip (122C), the greater the durability of the first cutting surface (123C) is, the greater the durability is compared to the second cutting surface (126C).

[0135] In addition, refer to Figure 8 (b) and Figure 8 (c) When the final tip (122C) is biased toward the first surface (114C) based on the center line (CL), the second thickness (b) tends to decrease more toward the substrate tip (122B) compared to the case where the final tip (122B) is located on the center line (CL).

[0136] Reference Figure 8 (d) With the center line (CL) as a reference, the first surface (114D) and the second surface (116D) of the substrate (110D) may be asymmetrical.

[0137] At this time, the shape of the first surface (114D) may correspond to the shape of the first cutting surface (123D), and the shape of the second surface (116D) may correspond to the shape of the second cutting surface (126D).

[0138] Furthermore, the second thickness (b) is formed to be greater than the first thickness (a), so that the thickness of the coating layer (120D) used to form the second cutting surface (126D) is relatively thicker, thereby improving the durability of the second cutting surface (126D).

[0139] Figure 8 (a) to Figure 8 (d) The embodiments shown in the figure are only some of the embodiments of the present disclosure. Therefore, the razor blade (10) according to an embodiment of the present disclosure may also have a plurality of Figure 8 (a) to Figure 8 (d) Shapes and structures other than those in the embodiment shown.

[0140] The following Figure 9 In another embodiment of the present disclosure, at least a portion of the first cutting surface has a convex profile. Figures 1 to 8The following mainly describes the distinguishing technical features of another embodiment of the present disclosure, and will not repeat the description of components that are substantially the same as those of the embodiment of the present disclosure.

[0141] Figure 9 is a simplified schematic diagram of an area near the final tip (222) of a razor blade (20) according to another embodiment of the present disclosure.

[0142] Reference Figure 9 According to another embodiment of the present disclosure, a shaving blade (20) may include a substrate (210) and a coating (220) stacked on the substrate (210).

[0143] The substrate (210) may include a substrate tip (212), a first side (214), and a second side (216).

[0144] The first face (214) and the second face (216) may extend from the substrate tip (212) and may be substantially symmetrical relative to a center line (CL) that passes through the substrate tip (212) and divides the substrate (210) in two.

[0145] At this time, in order to achieve the shape of the asymmetric cutting surfaces (223, 226), the coating layer formed on the first surface (214) and the coating layer (220) formed on the second surface (216) may have different thicknesses or different shapes.

[0146] However, the present disclosure is not limited thereto, and the first surface (214) and the second surface (216) may also be asymmetrical. In this case, the shape of the first surface (214) may correspond to the shape of the first cutting surface (223), and the shape of the second surface (216) may correspond to the shape of the second cutting surface (226).

[0147] The substrate (210) may include at least one of stainless steel, carbon steel, and ceramics. However, the present disclosure is not limited thereto, and the substrate (210) may also include other materials.

[0148] The coating (220) may include a final tip (222), a first cutting face (223), and a second cutting face (226).

[0149] A first cutting face (223) and a second cutting face (226) may extend from the final tip (222).

[0150] The first cutting surface (223) may correspond to the first surface (214) of the substrate (210) and be arranged adjacent to the first surface (214). The second cutting surface (226) may correspond to the second surface (216) of the substrate (210) and be arranged adjacent to the second surface (216).

[0151] The first cutting surface (223) may include a first tangent surface (224) extending from the final tip (222) and a second tangent surface (225) extending from the first tangent surface (224). A first straight line (L1) connected to the first tangent surface (224) and a second straight line (L2) connected to the second tangent surface (225) may not be parallel.

[0152] At least a portion of the first cutting surface (223) may have a convex profile. Therefore, the convex area of ​​the first cutting surface (223) may also be formed on the entire first cutting surface (223) or only on a portion of the first cutting surface (223).

[0153] When the protruding area of ​​the first cutting surface (223) is formed only on a partial area of ​​the first cutting surface (223), the protruding area of ​​the first cutting surface (223) can be formed on any one of the first cutting surface (224) and the second cutting surface (225), or the protruding area of ​​the first cutting surface (223) is formed on both the first cutting surface (224) and the second cutting surface (225).

[0154] In addition, the protruding area of ​​the first cutting surface (223) can be formed on the entire area of ​​at least one of the first cutting surface (224) and the second cutting surface (225), but can also be formed on only a partial area of ​​at least one of the first cutting surface (224) and the second cutting surface (225).

[0155] For example, when the protruding area of ​​the first cutting surface (223) is formed on the first cutting surface (224), the protruding area of ​​the first cutting surface (223) is formed in the middle area from the final tip (222) to the first cutting surface (224), or, is formed in the middle area from the first cutting surface (224) to the boundary position between the first cutting surface (224) and the second cutting surface (225).

[0156] When the first cutting surface (223) with the convex profile is a facial facing edge and the razor blade (20) is close to the skin (C) and almost in contact with it, the first cutting surface (123) will contact the skin (C) in more areas, thereby minimizing skin irritation caused by the razor blade (20). Therefore, the razor blade (20) according to another embodiment of the present disclosure has the effect of providing a comfortable shaving feeling to the user.

[0157] In addition, at least a portion of the first cutting surface (223), for example, the radius of curvature (Rc) of the first cutting surface (223) in the region of the razor blade (20) spaced 0.0 to 0.5 microns from the final tip (222) may be 0.5 to 1.5 microns, preferably 0.7 to 1.2 microns. Thus, the razor blade (20) according to another embodiment of the present disclosure can provide the user with a comfortable shaving sensation and also has excellent cutting force.

[0158] The second cutting face (226) may include a third facet (227) extending from the final tip (222).

[0159] The third section (227) may correspond to the first section (224) and the second section (225), that is, the third section (227) faces the first section (224) and the second section (225).

[0160] Unlike the first cutting surface (223) having a convex profile, the third cutting surface (227) of the second cutting surface (226) may have a substantially flat profile. Therefore, the first cutting surface (223) and the second cutting surface (226) may have an asymmetrical shape.

[0161] The final tip (222) can be located on the center line (CL). In this case, the final tip (222) and the base tip (212) can be arranged on the same line. When the base tip (212) and the final tip (222) are located on the center line (CL), in a state where the applied pressure is not dissipated by the torque, all the applied pressure transmitted from the base tip (212) to the final tip (222) can be used to cut body hair, so shaving can be performed with less force.

[0162] However, the present disclosure is not limited thereto, and the final tip (222) may be offset from the center line (CL). For example, the final tip (222) may be offset from the second surface (216) relative to the center line (CL). In this case, the coating (220) used to form the second cutting surface (226) may be relatively thicker, thereby improving the durability of the second cutting surface (226).

[0163] On the contrary, the final tip (222) can also be biased toward the first surface (214) with the center line (CL) as a reference. When the final tip (222) is biased toward the first surface (214) with the center line (CL) as a reference, the thickness of the coating (220) used to form the first cutting surface (223) can be relatively thicker, thereby improving the durability of the first cutting surface (223).

[0164] Additionally, at a position a predetermined distance away from the substrate tip (212), a first thickness (a) between the first surface (214) and the first cutting surface (223) may have a relatively larger value than a second thickness (b) between the second surface (216) and the second cutting surface (226).

[0165] By forming the first thickness (a) to be greater than the second thickness (b), the coating layer (220) used to form the first cutting surface (223) can be made relatively thicker, thereby improving the durability of the first cutting surface (223).

[0166] However, the present disclosure is not limited thereto. For example, the second thickness (b) may be relatively larger than the first thickness (a), or the first thickness (a) and the second thickness (b) may be substantially similar.

[0167] When the final tip (222) is located on the center line (CL), the closer the first thickness (a) is to the substrate tip (222), the greater the second thickness (b) may be. However, the present disclosure is not limited thereto, and the first thickness (a) and the second thickness (b) may be pre-set to be different depending on the design of the razor blade.

[0168] For example, when the final tip (222) is located on the center line (CL), at least one of the first thickness (a) and the second thickness (b) may become smaller or larger as it approaches the substrate tip (222), or the first thickness (a) and the second thickness (b) may both have substantially certain values.

[0169] The above description is merely an example of the technical concept of this embodiment. For those with ordinary knowledge in the technical field to which this embodiment belongs, various modifications and variations can be made without exceeding the essential features of this embodiment. Therefore, this embodiment is not intended to limit the technical concept of this embodiment but is used for illustration, and the scope of the technical concept of this embodiment is not limited by the embodiment. The scope of protection of this embodiment should be interpreted based on the attached claims, and all technical concepts within the scope of their equivalents should be interpreted as falling within the scope of rights of this embodiment.

[0170] [Explanation of Reference Signs]

[0171] 10: Razor blade 110: Substrate

[0172] 112: substrate tip 114: first surface

[0173] 116: Second side, 120: Coating

[0174] 122: Final tip 123: First cutting surface

[0175] 124: First section 125: Second section

[0176] 126: Second cutting surface 127: Third cutting surface

[0177] 128: Fourth section 129: Fifth section

[0178] CL: Central Line PL: Vertical Line

[0179] TA: Tip Angle WA: Wedge Angle

[0180] A1: First angle A2: Second angle

[0181] A3: Third corner A4: Fourth corner

[0182] H1 to H3: first to third horizontal lines

[0183] L1 to L6: First to sixth straight lines

[0184] P1 to P3: first to third positions

[0185] D1 to D8: first to eighth distance

[0186] [CROSS-REFERENCE TO RELATED APPLICATION]

[0187] This application is based on and claims the benefit of priority of Korean patent application No. 10-2020-0140236, filed on October 27, 2020, and Korean patent application No. 10-2021-0093298, filed on July 16, 2021, the entire contents of which are incorporated herein by reference.

Claims

1. A razor blade comprising: a substrate comprising a substrate tip and a first side and a second side extending from the substrate tip; as well as a coating layered on the substrate and comprising a final tip, a first cutting face, and a second cutting face, wherein the first cutting face and the second cutting face extend from the final tip and correspond to the first face and the second face, respectively; The first cutting surface includes a first tangent facet extending from the final tip and a second tangent facet extending from the first tangent facet, The second cutting surface includes a third facet extending from the final tip and corresponding to the first facet and the second facet, A first straight line connected to the first tangent plane is not parallel to a second straight line connected to the second tangent plane. The final tip is offset from a center line that passes through the substrate tip and bisects the substrate. A first distance between a perpendicular line passing through the final tip and parallel to the center line and the center line is 20 nanometers to 300 nanometers.

2. The razor blade according to claim 1, wherein: The third section has a flat profile.

3. The razor blade according to claim 1, wherein: The final tip is biased toward the second surface with respect to the center line.

4. The razor blade according to claim 1, wherein : At a position spaced a predetermined distance from the tip of the substrate, a value of a first thickness between the first face and the first cutting face divided by a second thickness between the second face and the second cutting face is 0.1 to 2.

5.

5. The razor blade according to claim 1, wherein: The angle between the first straight line and the second straight line, ie, the wedge angle, is 100 degrees to 160 degrees.

6. The razor blade according to claim 1, wherein: The angle between the first straight line and the third straight line connected to the third tangent plane, ie, the tip angle, is 55 degrees to 130 degrees.

7. The razor blade according to claim 1, wherein: The first straight line intersects the second straight line at a first position, and a second distance between a first horizontal line passing through the first position and perpendicular to the center line and the final tip is 50 nanometers to 400 nanometers.

8. The razor blade according to claim 1, wherein: A third distance between the substrate tip and the final tip is 100 nanometers to 600 nanometers.

9. The razor blade according to claim 1, wherein: The first straight line intersects the second straight line at a first position, and a fourth distance between the first position and the tip of the substrate is 100 nanometers to 400 nanometers.

10. The razor blade according to claim 1, wherein: The first straight line intersects the second straight line at a first position, and a fifth distance between the first position and the final tip is 100 nanometers to 600 nanometers.

11. The razor blade according to claim 1, wherein: The value of the angle between the first straight line and a third straight line connected to the third tangent plane, that is, the tip angle divided by the first angle between the second straight line and the third straight line is 1.5 to 3.

5.

12. The razor blade according to claim 1, wherein: The first straight line intersects the second straight line at a first position, a first horizontal line passing through the first position and perpendicular to the center line intersects the third section at a second position, and a sixth distance between the first position and the second position is 150 nm to 700 nm.

13. The razor blade according to claim 1, wherein: The first straight line intersects the second straight line at a first position, a first horizontal line passes through the first position and is perpendicular to the center line, a second horizontal line passes through the tip of the substrate and is parallel to the first horizontal line, and a seventh distance between the first horizontal line and the second horizontal line is 20 nanometers to 350 nanometers.

14. The razor blade according to claim 1, wherein: The second angle formed by the third straight line connected to the third tangent plane and the fourth straight line connected to the second surface is in a range from 10 degrees to 40 degrees.

15. The razor blade according to claim 1, wherein: At least a portion of the first cutting face has a convex profile.

16. The razor blade according to claim 15, wherein: At least a portion of the convex region of the first cutting surface has a radius of curvature of 0.5 micrometers to 1.5 micrometers.

17. A razor blade comprising: a substrate comprising a substrate tip and a first side and a second side extending from the substrate tip; as well as a coating layered on the substrate and comprising a final tip, a first cutting face, and a second cutting face, the first cutting face and the second cutting face extending from the final tip and corresponding to the first face and the second face, respectively; The first cutting surface includes a first tangent facet extending from the final tip and a second tangent facet extending from the first tangent facet, The second cutting surface includes a third facet extending from the final tip and corresponding to the first facet and the second facet, A first straight line connected to the first tangent plane is not parallel to a second straight line connected to the second tangent plane. The third section has a flat profile, A center line passes through the substrate tip to divide the substrate into two parts, and a first distance between a perpendicular line passing through the final tip and parallel to the center line and the center line is 20 nanometers to 300 nanometers.

18. A razor blade comprising: a substrate comprising a substrate tip and a first side and a second side extending from the substrate tip; as well as a coating layered on the substrate and comprising a final tip, a first cutting face, and a second cutting face, wherein the first cutting face and the second cutting face extend from the final tip and correspond to the first face and the second face, respectively; The first cutting surface includes a first tangent facet extending from the final tip and a second tangent facet extending from the first tangent facet, The second cutting surface includes a third facet extending from the final tip and corresponding to the first facet and the second facet, A first straight line connected to the first tangent plane is not parallel to a second straight line connected to the second tangent plane. A center line passes through the tip of the substrate so as to bisect the substrate. The angle between the center line and the first straight line is a third angle. The angle between a third straight line connected to the third tangent plane and the center line is a fourth angle. The third angle is different from the fourth angle. A first distance between a perpendicular line passing through the final tip and parallel to the center line and the center line is 20 nanometers to 300 nanometers.

Images