Razors with hair-cutting fibers

Abstract

A razor with hair-cutting fibers having hair-cutting sections attached to a support relative to a skin-engaging surface, the hair-cutting sections being exposed to the user's skin for cutting hair as the skin-engaging surface contacts and moves over the skin. The hair-cutting sections have a fiber diameter of 7 μm or less and are made of a fiber material with a tensile strength greater than or equal to 5 GPa. A shaving method using this razor is also described.

Description

Technical Field

[0001] This invention relates to a razor, the razor comprising:

[0002] Hair-cutting fibers having hair-cutting sections configured to cut hair on the user's skin by moving the hair-cutting sections through the hair.

[0003] Support member, wherein the opposite ends of the hair cutting sections are attached to the support member; and

[0004] Skin-to-skin interface surface;

[0005] The hair-cutting segment is attached to the support member relative to the skin-engaging surface in such a way that the hair-cutting segment is exposed to the skin for cutting hair when the skin-engaging surface contacts and moves on the skin.

[0006] The present invention also relates to a method for shaving hair on the skin using such a razor. Background Technology

[0007] Razors used for shaving have been known for centuries. Before the advent of electric dry shaving (using an electric shaver whose hair-cutting components rotate or oscillate by means of electricity), shaving was typically done with safety-blade razors and involved wetting the skin and hair to be shaved, softening the hair by applying a foaming agent (such as cream, shaving soap, gel, foam, or oil) as a lubricant. Lubricating and wetting the skin and hair to be shaved reduces irritation by reducing friction between the razor blade and the skin and hair being shaved. Although water and foaming agents need to be applied to the skin and hair to be shaved before shaving, and foaming agent residue needs to be removed after shaving, many people still prefer this so-called "wet shaving" using safety-blade razors.

[0008] WO2006 / 003641 discloses a razor of the aforementioned type in the "Field of Invention" section. This known razor includes a hair-cutting head in which a thin, heated wire is suspended for shaving, cutting, or burning hair growing from the skin. The wire has a diameter between 10 μm and 1000 μm and is made of a conductive metal. The wire is heated to a temperature of at least 700°C. When the heated wire comes into contact with hair, the hair melts, and as a result, the hair can be easily cut. A disadvantage of this known wire-based razor is that any contact between the heated wire and the skin must be prevented to avoid damage to the skin and electrical contact with the skin.

[0009] EP 0888733 A2 discloses a body hair removal tool comprising a pair of opposing and spaced-apart comb plates and an electric heating wire for burning and cutting body hair in contact with them. The opposing teeth of the opposing comb plates are fully or partially interconnected at their tips in an arched form surrounding the heating wire. Summary of the Invention

[0010] One object of the present invention is to provide a razor and a method for shaving hair of the type described in the preceding “Field of the Invention” section, the razor and method allowing hair close to the skin to be cut by hair-cutting fibers without heating the hair-cutting fibers and without first wetting the skin and hair to be shaved or first applying a foaming agent to reduce the cutting force required to cut the hair.

[0011] According to the present invention, this objective is achieved by providing a razor according to claim 1 and a method for shaving hair according to claim 16.

[0012] Because the razor according to the invention has hair-cutting fibers with a relatively small fiber diameter, single hairs can be cut using hair-cutting fibers with an acceptablely low cutting force (particularly below 0.06 N) without pre-wetting the skin and hair or preheating the hair-cutting fibers or hair. When the hair-cutting segment contacts the hair with such a low cutting force, the fiber diameter of 7 μm or less allows the hair-cutting segment of the hair-cutting fiber to form an initial notch on the hair. Subsequently, during further hair cutting, the frictional force exerted by the cut hair on the hair-cutting segment of the hair-cutting fiber is very small compared to the frictional force exerted by the cut hair on the safety razor blade, because the frictional contact area between the hair tissue and the hair-cutting segment is very small compared to blade shaving. Due to the relatively low frictional force during hair cutting, dry shaving can be performed at an acceptablely low cutting force without the need for a motor-driven movement of the hair-cutting member, and in particular, without the need to heat the hair-cutting fibers. Furthermore, in the razor according to the invention, the tensile strength of the fiber material of at least 5 GPa prevents the hair-cutting fibers from breaking under the influence of the required hair-cutting force during hair cutting. This tensile strength can be achieved by certain fiber materials.

[0013] The specific details and embodiments of the invention are set forth in the dependent claims.

[0014] Other features, effects and details of the invention will become apparent from the detailed description and accompanying drawings. Attached Figure Description

[0015] Figure 1 This is a perspective view of an example of a razor according to the present invention;

[0016] Figure 2 yes Figure 1 A plan view of a portion of the razor shown;

[0017] Figure 3 yes Figure 1 and Figure 2 A cross-sectional side view of a portion of the razor in use;

[0018] Figure 4 A plan view of a second example of a razor according to the invention; and

[0019] Figure 5 This is a plan view of a third example of a razor according to the present invention. Detailed Implementation

[0020] Figures 1-3 An example of a razor 1 according to the present invention is shown. Figure 1 The razor 1 shown has hair-cutting fibers 2 and a support 3, the hair-cutting fibers 2 being attached to the support 3. A handle 4 for holding and operating the razor 1 is attached to the support 3. Figure 2 and Figure 3 As shown, the hair-cutting fiber 2 has multiple hair-cutting segments 5 for cutting hairs 6 protruding from the skin surface 7 by moving the hair-cutting fiber 2 through the hair 6.

[0021] On opposite sides of the hair cutting segments 5, opposite ends 8 of the hair cutting segments 5 are attached to the support member 3. The support member 3 has a skin-engaging surface 9. The hair cutting segments 5 are attached to the support member 3 relative to the skin-engaging surface 9 in a position such that when the skin-engaging surface 9 contacts and moves over the skin 7, the hair cutting segments 5 are exposed to the skin 7 for cutting hairs 6 protruding from the skin. Each hair cutting segment 5 has a fiber diameter less than or equal to 7 μm, and the hair cutting segments 5 are made of a fibrous material with a tensile strength greater than or equal to 5 GPa. Preferably, each hair cutting segment 5 has a fiber diameter less than or equal to 4 μm, and more preferably, each hair cutting segment 5 has a fiber diameter less than or equal to 2 μm. Preferably, the hair cutting segments 5 are made of a material with a tensile strength greater than or equal to 6 GPa, and more preferably greater than or equal to 10 GPa.

[0022] For ease of manufacture, preferably all hair-cutting fibers 2 are made of the same material. The hair-cutting segments 5 can be made, for example, of a high-tensile-strength carbon fiber material. An example of such a fiber material is Toray. TMT1100S, which is commercially available and has a tensile strength of 7 GPa. To achieve even higher tensile strength, the hair-cutting segment 5 may comprise or be in the form of carbon nanotubes or graphene fibers. Such fibrous materials are disclosed, for example, in:

[0023] —Xu et al. (2016), “Ultrastiff and strong graphene fibers via full-scale synergetic defect engineering.” Advanced Materials, 28(30): 6449-6456.

[0024] —Xu et al. (2015), “Graphene fiber: a new trend in carbon fibers.” Materials Today, Vol. 18, No. 9, 2015, pp. 480-492.

[0025] —Bai et al. (2018), “Carbon nanotube bundles with tensile strength over 80 GPa”. Nature Nanotechnology, 13(7): 589-595.

[0026] Over time, many innovations in blade shaving technology have aimed to reduce hair-cutting forces, such as by applying Teflon and diamond-like carbon coatings to the blade tips and by applying special blade tip shapes. These innovations have allowed for shaving using multiple blades in a blade holder while keeping resistance during shaving at an acceptable level. However, resistance remains considerable, especially when attempting to shave without wetting and lubrication, because a significant amount of blade material comes into contact with the hair during hair cutting, resulting in considerable friction between the blade and the hair.

[0027] When cutting with fibers, the cutting load applied to the "cutting element" differs significantly from that applied to a conventional cutting blade. The cutting edge of a conventional blade is supported by a large amount of material adjacent to the cutting edge. This results in compression of the bulk material directly behind the cutting edge and, depending on the blade's mounting, slight bending stresses within the bulk material. When cutting with flexible fibers, which can be wires, the cutting force generates considerable tensile stresses within the fibers. When cutting very weak materials such as soft cheese, the tensile stress remains below the tensile strength of steel. However, when cutting harder materials such as wood, the tensile stress tends to exceed, and even exceed, the tensile strength of the strongest types of steel.

[0028] The yield strength and Young's modulus of beard hair and other human hair are roughly within the range of those of wood. Therefore, it is clear that the tensile stress generated in the fibers of cut hair will generally exceed the tensile strength of ultra-high tensile strength steel wire.

[0029] Furthermore, because hair is relatively thin and therefore flexible, the fiber diameter needs to be very small in order for the fiber to cut through hair with free ends protruding from the skin surface. This allows for the creation of an initial notch within the hair without bending the hair to the point where the fiber slips off the surface of the hair to be cut. Typical blade cutting edges have a tip radius in the range of 0.05 μm–0.1 μm to create the initial notch. The force required to create this initial notch with such a sharp edge is less than 0.001 N. This initial notch-generating force is important for cutting hair with fibers. The maximum cutting force when the fiber passes through the hair material at its maximum hair diameter is also relevant, as this maximum cutting force determines the tensile strength required for the fiber.

[0030] As the fiber diameter increases and decreases, the cutting force increases and decreases accordingly, while the tensile strength of the fiber varies with the cross-sectional surface area, i.e., it is proportional to the square of the diameter. Therefore, for example, when the fiber diameter decreases by half, the tensile strength decreases by a factor of four.

[0031] The present invention is based on the understanding that there is still a window for fiber diameter, wherein, on the one hand, the notch forming force and cutting force are low enough to allow the fiber to cut the hair without causing excessive tilting and bending of the hair, and on the other hand, the tensile stress requirements can be met by certain fiber materials.

[0032] Because the razor 1 has hair-cutting fibers 2 with relatively small fiber diameters, individual hairs 6 can be cut using acceptable low cutting forces, particularly below 0.06 N, without pre-wetting the skin surface 7 and hair 6 or preheating the hair-cutting fibers 2 or hair 6. When the hair-cutting segment 5 contacts the hair 6 with such a low cutting force, the fiber diameter of 7 μm or less allows the hair-cutting segment 5 of the hair-cutting fiber 2 to form an initial notch on the hair 6. Subsequently, during further cutting of the hair 6, the frictional force exerted by the hair 6 on the hair-cutting segment 5 of the cut hair-cutting fiber 2 is very small compared to the frictional force exerted by the hair on the cut safety razor blade, because the frictional contact area between the hair tissue and the hair-cutting segment 5 is very small compared to blade shaving. Due to the relatively low frictional force during hair cutting, dry shaving can be performed at acceptable low cutting forces without the need for motor-driven movement of the hair-cutting component, and in particular, without the need to heat the hair-cutting fibers 2. The fiber material has a tensile strength of at least 5 GPa to prevent the hair-cutting fiber 2 from breaking under the influence of the required hair-cutting force during hair cutting. This tensile strength can be met by certain fiber materials.

[0033] It has been found that during the cutting process, the bending radius of the hair-cutting fibers 2 surrounding the cut hair 6 has a significant impact on the maximum tensile stress in the hair-cutting fibers 2. The contribution of the bending radius to the tensile stress increases as the diameter of the hair-cutting fibers 2 increases and as the bending angle of the hair-cutting fibers 2 around the hair 6 increases during cutting. By optimizing the degree of bending of the hair-cutting fibers 2 during cutting, the tensile stress of the hair-cutting fibers 2 during cutting can be minimized. To maintain sufficiently low bending stress and friction, the fiber diameter of the hair-cutting segment 5 is preferably less than or equal to 4 μm.

[0034] To avoid excessive tensile stress, it is preferable that the fiber diameter of the hair cutting segment 5 is greater than or equal to 0.5 μm. Considering the availability of fibers with sufficient strength and the need to avoid using excessively expensive fibers, the tensile strength of the fiber material is preferably less than or equal to 80 GPa, more preferably less than or equal to 50 GPa.

[0035] like Figure 3 As shown, in use, the skin-engaging surface 9 contacts the skin 7 and moves over the skin 7 in the shaving direction 12. The hair-cutting segment 5 of the hair-cutting fiber 2 is attached to the support 3 in a position such that the hair-cutting segment 5 moves along the skin 7. The distance d between the hair-cutting segment 5 and the skin-engaging surface 9 is selected such that the skin 7, which protrudes in front of the skin-engaging surface 9 and enters the free space 11 in which the hair-cutting segment 5 is disposed, at most makes only slight contact with the hair-cutting segment 5.

[0036] While shaving can also be done without water and / or shaving lubricant applied to the skin—that is, when the skin is mostly dry—the skin can be moistened and / or shaving lubricant applied, depending on personal preference, and to further reduce friction and enhance the cutting action. The razor then provides a particularly comfortable and low-friction shaving experience.

[0037] To maintain a low tensile load on the hair-cutting fiber 2 during cutting, it is preferable to suspend the hair-cutting fiber 2 to allow for significant drooping of the hair-cutting segments 5 during cutting. For this purpose, the hair-cutting fiber 2 is preferably suspended by a support 3 such that, in the unloaded state, each hair-cutting segment 5 extends between its opposing ends 8 as a curved portion of the hair-cutting fiber 2. Figure 2 As shown in detail, the hair-cutting segment 5 preferably protrudes from the opposite end 8 of the hair-cutting fiber 2 attached to the support member 3 at an angle α of at least 25° relative to the straight line extending through the opposite end 8 of the hair-cutting segment 5. To avoid excessive bending of the hair-cutting segment 5 around the hair during cutting, the hair-cutting fiber 2 is preferably suspended such that, in the unloaded state, the hair-cutting segment 5 protrudes from the opposite end 8 of the hair-cutting fiber 2 attached to the support member 3 at an angle α of at most 65° relative to the straight line extending through the opposite end 8 of the hair-cutting segment 5. The deflection relative to the straight line extending through the opposite end 8 of the hair-cutting segment 5 is preferably in the opposite direction to the shaving direction 12 in which the razor 1 moves over the skin 7.

[0038] To provide sufficiently high hair-catching capability for the hair-cutting fibers 2, the razor 1 has multiple hair-cutting segments 5, each suspended in a corresponding open space among multiple open spaces 11 disposed in the support 3. Another advantage of having multiple hair-cutting segments 5 is that if a hair-cutting segment 5 breaks, the other hair-cutting segments 5 can still be used to cut hair, thus allowing continued shaving. Figure 2 In the example, the hair cutting segments 5 are arranged in a straight line and each is suspended in an open space 11 between opposite portions 10 of the support 3, so that the hair cutting segments 5 can easily follow the curvature of the skin 7 surface in a direction perpendicular to the row.

[0039] exist Figure 2In the example, the support 3 has a comb structure, wherein an open space 11 is disposed between successive pairs of adjacent comb teeth 10 of the comb structure. The opposite ends 8 of each hair-cutting segment 5 are each attached to a corresponding tooth in the pair of adjacent comb teeth 10 associated with that hair-cutting segment 5. However, the support may also be provided in other forms, such as as a support portion arranged along an opening (e.g., a hole or slit) in the support or as a support portion arranged along a recess in the skin-engaging surface of the support.

[0040] Preferably, the open space 11 has a width e of less than or equal to 0.6 mm in the main extension direction of the hair cutting segment 5 suspended in the open space 11, such that only a single hair 6 can enter the open space 11 at a time and be cut by the hair cutting segment 5 arranged in the open space 11. This avoids the simultaneous application of cutting loads by two or more hairs on the same hair cutting segment 5. To ensure that the hair to be cut fits individually into each open space of the open space 11 between the comb teeth 10 of the support 3, the hair cutting segment 5 is suspended in the open space, and the width e of the open space 11 is preferably greater than or equal to 0.1 mm. The limited width e of the open space 11 also restricts the uncontrolled free movement of the loosely suspended hair cutting segment 5 and excessive skin bulges (protrusions) into the open space 11 (see...). Figure 3 Therefore, accidental cuts to the skin or excessive abrasion or other irritation to the skin tissue can be avoided. Support 3 can be made of metal such as stainless steel, but can also be made of other materials such as plastic or ceramic.

[0041] The opposite ends 8 of the hair-cutting fibers 2 can be attached to the comb teeth 10 of the support 3, for example, by adhesive and / or by mechanical clamping. The support 3 can be rigid or flexible to allow it to conform to the contours of the skin 7 during use.

[0042] In this example, the position of the hair-cutting segment 5 relative to the surface of the skin 7 is controlled precisely and simply because the skin-engaging surface 9 includes the skin-engaging tooth surface of the comb teeth 10. However, other arrangements are also conceivable. For example, the skin-engaging surface can be formed on a housing in which the support to which the hair-cutting fibers are attached is releasably mounted. This would allow for replacement of the support including the hair-cutting fibers if too many breakages occur. Furthermore, the support and hair-cutting fibers can be designed to serve as replacements for conventional replaceable razor blades, or as replacements for conventional razor blade holders, with or without the skin-engaging surface on the support.

[0043] In this example, multiple hair-cutting segments 5 form portions of a single hair-cutting fiber 2. This facilitates the manipulation of the hair-cutting fiber 2 during the manufacture of the razor 1. However, it is also possible that two or more sets of hair-cutting segments are each portion of two or more separate hair-cutting fibers, such that the hair-cutting segments form portions of two or more hair-cutting fibers. Furthermore, in... Figure 4 and Figure 5 In the example shown, each hair-cutting fiber 52 may have only a single hair-cutting segment 55, 105. Figure 4 and Figure 5 In this diagram, not all corresponding components are indicated by reference numerals. For example... Figure 4 As shown, the opposite ends 58 of each hair cutting segment 55 are mounted on a corresponding tooth of a pair of adjacent comb teeth 60, such that each hair cutting segment 55 extends in a corresponding open space of the open space 61 between the pairs of adjacent comb teeth 60.

[0044] For example Figure 4 As shown, multiple parallel rows of hair-cutting segments 55 for cutting in the shaving direction 62 can be arranged in a single support 53. This arrangement provides precise spacing between the skin stretching surface 63 and the hair-cutting segments 55, as well as the multiple skin engagement surfaces 59, for uniform distribution of shaving pressure.

[0045] like Figure 5 As shown, the row of hair cutting segments 105 can be curved, thus forming a raised boundary of the skin-engaging surface 109, allowing for better adaptation to some curvatures of the face. For other curvatures, the concave boundary of the skin-engaging surface 109 can provide better adjustment.

[0046] Although the invention has been described and illustrated in detail in the foregoing description and drawings, such description and illustration should be considered exemplary and / or illustrative rather than restrictive; the invention is not limited to the disclosed embodiments.

[0047] Several features have been described as part of the same or individual embodiments. However, it should be understood that the scope of the invention also includes embodiments having all or some of these features, rather than specific combinations of features embodied in the embodiments.

[0048] By studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand and implement other variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. A single processor or other unit may implement the functions of several items as described in the claims. For the purpose of clarity and concise description, features that are part of the same or separate embodiments are disclosed herein; however, it should be understood that the scope of the invention may include embodiments having a combination of all or some of the disclosed features. The fact that certain measures are recited in mutually different dependent claims does not imply that combinations of these measures cannot be advantageously used. Any reference numerals in the claims should not be construed as limiting the scope.

Claims

1. A razor comprising: Hair-cutting fibers having hair-cutting sections configured to cut hair on a user's skin by moving the hair-cutting sections through the hair. A support member to which the opposite ends of the hair-cutting sections are attached; as well as Skin-to-skin interface surface; The hair-cutting segment is attached to the support relative to the skin-engaging surface in such a way that the hair-cutting segment is exposed to the skin for cutting the hair when the skin-engaging surface contacts and moves over the skin. Its features are: The hair cutting segment has a fiber diameter of less than or equal to 7 μm; and The hair cutting section is made of fibrous material with a tensile strength greater than or equal to 5 GPa.

2. The razor of claim 1, wherein the hair-cutting section is made of carbon.

3. The razor according to claim 2, wherein the hair cutting segment comprises carbon nanotubes or graphene fibers.

4. The razor according to any one of claims 1-3, wherein the hair-cutting section extends between the opposite ends as a curved portion of the hair-cutting fiber.

5. The razor according to any one of claims 1-3, wherein the razor comprises a plurality of hair-cutting sections, each of the plurality of hair-cutting sections being suspended in a corresponding open space of a plurality of open spaces disposed in the support member.

6. The razor according to claim 5, wherein each of the open spaces has a width of less than or equal to 0.6 mm in the main extension direction of the hair cutting section suspended in the respective open space.

7. The razor of claim 5, wherein the support includes a comb structure, and wherein the open space is disposed between successive pairs of adjacent comb teeth of the comb structure.

8. The razor of claim 7, wherein the opposite ends of each hair-cutting segment are each attached to a corresponding tooth of the pair of adjacent comb teeth associated with the hair-cutting segment.

9. The razor of claim 7, wherein the skin-engaging surface comprises the skin-engaging tooth surface of the comb teeth.

10. The razor of claim 5, wherein the plurality of hair-cutting segments form portions of a single hair-cutting fiber.

11. The razor of claim 5, wherein the plurality of hair-cutting segments form at least two separate portions of hair-cutting fibers.

12. The razor according to any one of claims 1-3 and 6-11, wherein the opposite ends of the hair cutting sections are attached to the support and / or clamped to the support by an adhesive.

13. The razor according to any one of claims 1-3 and 6-11, wherein the fiber diameter of the hair cutting segment is greater than or equal to 0.5 μm.

14. The razor according to any one of claims 1-3 and 6-11, wherein the fiber diameter of the hair cutting segment is less than or equal to 4 μm.

15. The razor according to any one of claims 1-3 and 6-11, wherein the tensile strength of the fibrous material is less than or equal to 80 GPa.

16. A method for shaving hair present on the skin, comprising: - Provide a razor according to any one of claims 1-15; as well as - The razor's skin-engaging surface is brought into contact with the skin, and the razor is moved over the skin, so that the skin-engaging surface is brought into contact with the skin, causing the hair-cutting segment of the razor's hair-cutting fibers to cut the hair.

17. The method of claim 16, wherein the hair, the skin, and the hair cut fibers are dry.

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