Patent Application
20120317818
This invention relates to shaving razors and more particularly to shaving razor cartridges having a skin contact element disposed between two blades.
Many razors for wet shaving on the market today have one or more razor blades (with many having three to six razor blades) within a razor cartridge which is operatively coupled to a handle, some razors being disposable and some razors having a reusable handle. Razor cartridges having multiple blades are described, for instance, in US Patent Publication No. 2005/0039337A1 published on Feb. 24, 2005, and one such razor cartridge has been commercialized as the five bladed Fusion™ Razor by The Gillette Company.
While multiple blades provide an improved close shave, generally some performance issues may still arise. Firstly, some discomfort may be realized by users during shaving. Secondly, shaving is still a relatively slow and inefficient process due to missed hairs and the difficulty in shaving problem areas such as the neck. Many shavers discern a substantial amount of missed hairs (e.g., hairs which are not cut at all or hairs that are not cut close to the skin or at the skin line) despite the bulk of hairs being cut.
In addition, it has been shown that some areas (e.g., neck, chin, and/or face) are particularly hard to shave. These areas generally have low-lying hairs that are often oriented in different directions. These low-lying hairs may be close, flat, or flush against the skin. In many instances, the user has to shave the same area repeatedly in attempting to cut hair that was either uncut or not cut close enough to the skin, resulting in increased skin irritation.
The discomfort aspect may be due to the increased number and sharpness of the blades and the cumulative force or loading on the skin, particularly in cartridges with three or more sharp blade edges.
Some prior art solutions which attempt to lessen the discomfort while maintaining safety and closeness provide, among other attributes, a reduced span of the blades from tip to tip, often referred to as the blade tip span. While such a reduction is generally known to provide better skin management by reducing the skin bulge between blades, it is also known to reduce the rinse-ability of hair clippings, skin particles, shaving cream, and/or other debris between the blades as the narrower spans decrease the size of the rinse-through gaps between the blades.
An alternative prior art solution to reducing discomfort by reducing blade load has been to increase the number of blades. Prior art applications introduce additional blades or elements attached to the blades. However, these interact with hair such that hair is displaced from an optimal cutting position when the blades engage with hair. No consideration is given as to how to reduce blade load and manage skin bulge whilst minimising any interaction with hair. Solid inter-blade elements or inter-blade elements which comprise a large skin contact area, such as those disclosed in the art, can lead to hair becoming trapped and consequently to less efficient cutting and greater irritation. Thus, there is still a need to improve skin management without hair interaction.
The invention provides a razor cartridge comprising a housing; a guard located at the front of the housing; a cap located at the rear of the housing; two or more blades disposed in the housing between the guard and the cap; a skin contact element extending across the housing between two of said blades; and a plurality of projections extending from a base of said skin contact element, each having a skin contacting surface, the projections being spaced along the length of the skin contact element, wherein there is a pitch of up to 2 mm between adjacent projections and the skin contacting surface has a width (w) extending for up to 35% of the pitch.
The frequency of projections across the skin contacting element provides contact points with the surface being shaved. As the skin contact surface extends for up to 35% of the pitch, sufficient support and control is provided to the skin surface while still allowing sufficient room for hair to pass through the skin contact element. As such, the present invention allows the reduction of load on a razor cartridge without the addition of any extra blades, whilst minimising with the impact on hair being shaved.
While the specification concludes with claims particularly pointing out and distinctly claiming the subject matter which is regarded as forming the present invention, it is believed that the invention will be better understood from the following description which is taken in conjunction with the accompanying drawings in which like designations are used to designate substantially identical elements, and in which:
This invention relates to a razor cartridge in a razor for wet shaving having a skin contact element disposed between two blades within a blade array. The term “skin contact element” as used herein, signifies a physical structure which generally does not cut hair or skin but contacts, engages, controls, enhances, agitates or stretches a user's skin providing skin management (e.g., reduction of skin bulge) during shaving and which comprises a plurality of projections. A “blade array” as used herein is defined as an array of one or more razor blades (e.g., generally multiple blades), each blade having a cutting edge where each cutting edge is generally facing in the same direction. Blade cutting edge or blade edge may be used interchangeably with blade tip herein, where a blade tip may represent a point on a blade edge. The razor cartridge may be considered as having a “mixed blade array” with mixed functionality in that there are cutting and skin contact elements in the array.
It should be noted that, generally, the guard 16 (and/or guard bar 16a) of a razor cartridge 10 disposed at the front of the cartridge is known to produce higher friction at the front of the cartridge stretching the skin ahead of the blades and desirably supporting or aligning hairs during the shaving process, while the cap 17 is generally known to be a low friction element located at the back of the cartridge allowing the skin to glide past the back of the cartridge while assisting in maintaining skin stretch. The cap may desirably also provide lubrication, smooth glide or other skin control.
Although four blades are shown in
The skin contact element 14 may advantageously be installed just as a regular or standard blade (e.g., blade with blade support or bent blade) or it may be installed having spring-loaded capabilities.
Referring now to
Referring now to
In
As can be seen in
The pitch between adjacent projections is measured from corresponding points on each projection in a lengthwise direction along the cartridge. The projections have a pitch 53a, 53b, 53c, of up to 2 mm extending across the length of the skin contact element, preferably up to 1.75 mm and even more preferably up to 1.5 mm. The skin contacting surface 54a, 54b, 54c may be about 0.10 mm to about 0.70 mm in width and desirably about 0.2 mm to about 0.3 mm, such that the skin contacting surface extends for up to 35% of the pitch, preferably up to 25% of the pitch and even more preferably up to 15% of the pitch.
The skin contacting surface provides a contact point with the skin, allowing the skin to be controlled. As the skin contact surface extends for up to 35% of the pitch, sufficient support and control is provided to the skin surface while still allowing sufficient room for hair to pass through the skin contact element. As such, the present invention allows the reduction of load on a razor cartridge without the addition of any extra blades, whilst minimising with the impact on hair being shaved.
Referring to the close-up view in
The pair of adjacent projections 51d, 51e, 51f, as mentioned define the slot 55 that is configured to allow hairs through with little or no interaction with the hair so the hair is not captured, trapped or pulled by projections 51d, 51e, 51f, which may cause discomfort. The slots 55 are spaced so as to not impede the hair. The projections 51d, 51e, 51f, are also configured to reduce skin bulges within the slots 55 and pressure points at ends of slots 55 which may result if the projections 51d, 51e, 51f are spaced too far apart. Skin bulges may lead to the blade edges (e.g., in particular blade 12d, not shown) unnecessarily cutting the skin, resulting in discomfort. The relatively large number of projections 51d, 51e, 51f, over the length of the skin contact element 50d, 50e, 50f, serves to distribute the force placed on the skin by the cartridge 10. As the size of the slots 55 may also increase the number of hairs passing through the slots 55 of the skin contact element, this may increase the number hairs that are properly cut by the blade edge 13d of blade 12d (not shown) for instance, if arranged as in
Each projection comprises a front face 56, a rear face 57 and a top face 58. The top face forms at least part of the skin contacting surface 54d, 54e, 54f, however in embodiments this also extends onto the front face of the projection 51d, 51e, 51f. Each projection has a height measured from a base 52, to the top face 58, of the projection 51d, 51e, 51f. Each projection has a depth as measured from the front face 56 of the projection to the rear face 57 of the projection. The top face and the front face of the projections 51d, 51e, 51f may be joined by a curved section 59 which may form part of the skin contacting surface 54d, 54e, 54f. The projections 51d, 51e, 51f may comprise a substantially flat portion on the top surface. Each projection has a rear edge 57d′, 57e′, 57f′.
The skin contacting surface 54d, 54e, 54f may have a width w of about 0.10 mm to about 0.70 mm and preferably about 0.2 mm to about 0.3 mm. The height as measured from the base 52, to the top face 58, of the projection 51d, 51e, 51f may be of about 0.25 mm to about 1 mm and preferably about 0.50 mm. Each projection generally has a depth of between about 0.3 mm to about 2.5 mm and preferably about 0.8 mm as measured from a front face of the projection 53 to a rear face of the projection 54.
The projections 51a, 51b, 51c may comprise a curved section 59 of up to 0.3 mm in length which joins the front face and the top face. The projections 51d, 51e, 51f may comprise a substantially flat portion on the top face of up to 0.6 mm in length. The rear edge 57′ of the projection 51d, 51e, 51f, may be at an angle θ of from +45° to −60° as measured from the top face to the base. Preferably the angle θ is from +10° to −30°.
The skin contact element of the present invention may be made of any type of material such as, but not limited to, polymeric, elastomeric, thermoplastic elastomers, urethanes, olefins, rubbers, metals, or any combination thereof. Elastomers such as silicone, fluorosilicone, polyisoprene, polybutadiene, polyisobutylene, copolymers such as styrene-ethylene-butylene-styrene (SEBS) based thermoplastic elastomer, styrene-ethylene-propylene-styrene (SEPS) based thermoplastic elastomer, polyoxyethylene-polyurethane based elastomer, or other polymers such as polyurethane, polystyrene and polyethylene, or rubbers such as acrylonitrile-butadiene, polyacrylate and natural rubber, or any combination thereof are also contemplated in the present invention. Additionally, the skin contact element material may include modifications of one or more of the above-listed materials (e.g., polymers and rubbers and their composites) with other materials.
If made of a polymeric or other elastomeric material, the skin contact element may be injection-molded. If made of metal, such as aluminium or stainless steel, the skin contact element may be machined or tooled.
Furthermore, the materials for a skin contact element may include textile or fabric materials, natural materials (e.g., wood), or metals coated or integrated with elastomeric or plastic materials.
The skin contact element may include materials with lubricant, shaving aid, or exfoliation capabilities. The term “shaving aid material” as used herein signifies any composition for use with skin and/or hair. Such compositions may include, but are not limited to, lubricious agents such as hydrophilic polymers (e.g., polyethylene oxide/polystyrene or PEO/PS), or agents for depilation, cleaning, cooling, inhibiting or enhancing the growth of hair, inhibiting the growth of microbes, inhibiting drag, inhibiting wrinkles, moisturizing, improving skin tone or condition, medicinal purposes, or any combination thereof. Agents may include, but are not limited to, ingredients such as aloe, vitamin E, lanolin, perfumes, or glycolic acids.
One factor which affects how a blade is presented to the skin is the exposure or the amount a blade is pressed into or lifted away from the skin impacting the blade loading on the skin. Another factor which affects how a blade is presented to the skin is the span between elements (e.g., such as between blades), which impacts the skin bulge ahead of the blade, and also impacts the blade loading on the skin. It is also known in the shaving arts that, in addition to exposures and spans, the management of skin and hair may also be affected by many additional inter-related variables such as the number of blades in a razor cartridge, the types of blades, and the angles of the blades relative to the skin line. The skin contact element of the present invention has the ability to provide additional control of these inter-related variables in the blade array impacting skin management. For instance, the skin contact element provides an improved control point for the blade loading on the skin.
In
Having a first rinse-through gap 23a disposed before the skin contact element 14 allows any excess hair that is cut by the second blade 12b or other debris to flow into this gap 23a, avoiding clogging the blades further back in the cartridge. Furthermore, second rinse-through gap 23b, disposed after the skin contact element 14 may provide an area for cut hairs to flow into (e.g., hairs that are cut by the third blade 12d directly behind the skin contact element 14).
First rinse-through gap 23a and second rinse-through gap 23b may be the same width or one gap may be of a smaller width than the other. For instance, it may be desirable to design first rinse-through gap 23a with a smaller width than second rinse-through gap 23b since blade 12e may have more cut hairs and excess debris flowing in between skin contact element 14 and blade 12e.
As shown in
Though shown disposed in the 3rd or middle blade position of a five-bladed razor cartridge 10 in
The present invention further contemplates having more than one skin contact element 14 disposed in the blade array 12 of cartridge 10, as shown in the illustrative embodiments of
Generally however, with little to no change to the structure of cartridge 10 or its housing 19, where a housing generally includes a frame 15 and a guard 16, any variation of types and numbers of blades and one or more skin contact elements 14 may be provided in the present invention.
It is known that blade exposure may impact the skin loading on the blade, which in turn may affect shaving attributes such as comfort, safety and efficiency. Thus, referring now to
The blades as arranged together in
The negative exposure 43 for blades 12a and 12b may desirably be in the range from about −0.18 mm to about −0.01 mm and more desirably about −0.07 mm while the positive exposure 41 for blades 12d and 12e may desirably be in the range from about 0.18 mm to about 0.48 mm, and more desirably about 0.33 mm.
In general, having some positive and some negative exposures in the blade array may be preferred since blades with some negative exposure may be better at protecting the skin while optimally cutting the hair and blades with some positive exposure may be better at releasing trapped hairs. However, it may also be preferred to have neutral or zero exposures throughout the array such that the skin just skims the surface, substantially minimizing the contact with the blades and therefore, improving shaving attributes such as comfort and safety.
As can be seen, a positively exposed blade, such as blade 12e from
While conventional razors aptly control skin and hair flow across an entire razor cartridge or blade array, the addition of one or more skin contact elements within the blade array 12 (desirably centrally located) advantageously inserts at least one more control point for skin, thereby allowing greater control over the geometry for individual or small groups of blades, fine tuning skin bulged, exposure and also blade tip loading for much improved comfort and cutting of hair (e.g., in closeness and number) and hence, shaving performance, as will be described below.
It should be noted that in the above-described embodiments of
Referring now to
The skin contact element 14 may lie on the same plane as the blades 12a, 12b, 12d, and 12e of the blade array 12 or on a different plane or any combination thereof. The skin contact element 14 may also lie on the same plane as blades 12b and 12d, but on a different plane from the plane of blades 12a or 12e. The latter arrangement would provide a neutral exposure for blades 12b and 12d relative to the skin contact element 14 and may lower the blade tip loading on the skin near the area of the skin contact element as those blades may just skim the skin.
It may be also preferred to adjust the blades' exposures such that blade 12d is set at a negative exposure relative to the skin contact element 14. For example, as can be seen in
With the presence of a skin contact element in the blade array, all the blades may desirably be substantially prevented from coming into contact with the skin (e.g., improved comfort, glide and safety), but the boosting of the height of the hair provides expanded blade contact with the hair combined with the blades' minimal to no contact with the skin (e.g., in particular at the blade 12d behind the skin contact element 14 as described above) improves the cutting of the hair.
However, were the skin contact element 14 of
Furthermore, having one or more skin contact elements disposed in the blade array may advantageously allow even sharper blades (e.g., with low cutting forces) or other blade arrangements to be utilized, without which, in a conventional razor may be too sharp (e.g., dangerous risk of cutting) or uncomfortable for users. For example, a very sharp type blade may desirably be disposed in the blade position directly behind such a skin contact element (e.g., blade 12d).
The inter blade span of the present invention may range from about 0.5 mm to about 2 mm. Preferably the interblade span is from 0.95 mm to 1.05 mm.
With the knowledge that the blade may substantially not contact the skin, or just skim the skin as shown in
Referring particularly to the BTA, it is generally known to signify the angle between the blade and the skin line. Increasing this angle may also allow the second stage to catch hairs that a more conventional first stage or cartridge unit 10a may have missed. However, adjustments to the BTA require some forethought in design as it is generally known that a higher BTA may improve closeness (e.g., more hairs cut), but typically at the expense of comfort (e.g., blades may drag on skin and damage it) whereas in contrast, a lower BTA may improve comfort, but typically at the expense of closeness.
With regard to BTAs,
In
Such a cartridge may advantageously provide a application of the skin contact element of the present invention. For instance, a cartridge may be choicefully designed to have different functionality before and after a centrally located skin contact element and hence, target different types of hair and/or different hair areas (e.g., neck, chin, face, body). For instance, the cutting of difficult, low lying hair may be improved with the arrangement of
Thus, in arranging a cartridge with the skin contact element(s) of the present invention providing a generally central control point, a balancing of the several inter-related variables such as blade types, angles, spans, exposures, and number of blades relative to control points such as the skin contact element, guard and cap, may generally be important for providing optimal designs that will not damage the skin while also effectively cutting the hair.
The presence of the skin contact element or control point of the present invention makes available a wider range of possibilities for the fine-tuning of these inter-related variables than permitted in conventional razor cartridges and thereby may provide more advantages.
As mentioned above, desirably blade sharpness and angles may be increased, spans may be decreased and exposures may be neutral or negative to provide undamaged skin and to cut more hair (both in extent and number). Furthermore, the skin contact element shall desirably allow skin and hair to pass without generating high friction thus maintaining the skin contact element as a substantially low friction element within the blade array.
While the skin contact elements described thus far are generally loaded into or installed into blade positions or slots from the top of the blade array or cartridge (e.g., similar to razor blade installation), the present invention is not limited to placement of skin contact elements in conventional blade positions or blade slots.
Other methods of manufacturing a skin contact element for placement within a blade array will be disclosed below.
The skin contact element of the present invention may, for instance, be loaded into the blade array 62 via at least one hole, aperture or slot 65a disposed in at least one of the sides of the cartridge frame 65 as shown in
Thus far, the skin contact element of the present invention has been described as being an independent, standalone, or separable element or elements, much like the razor blades themselves. Given that the instant element is a skin contact element with no cutting edges, alternate methods for providing such a skin contact elements in a razor cartridge may also be within the scope of the present invention. Such alternative embodiments of the present invention are described below.
Referring now to
Additionally, in
Though the skin contact element 74 may be formed as a portion of the frame 75 and skin contact element 84 may be formed as a portion of the clips 88a, 88b, both being formed as part of another razor component, they are generally not attached to or integrated with any of the blades, but this is contemplated within the scope of the present invention. The shaving advantages attributed to having at least one skin contact element within the blade array remain unchanged.
Additionally, it should be noted that the skin contact element of the present invention may be utilized in any type of razor cartridge and thus naturally in both male and female type razors.
The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm”.
Every document cited herein, including any cross referenced or related patent or application, is hereby incorporated herein by reference in its entirety unless expressly excluded or otherwise limited. The citation of any document is not an admission that it is prior art with respect to any invention disclosed or claimed herein or that it alone, or in any combination with any other reference or references, teaches, suggests or discloses any such invention. Further, to the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern.
While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 11170574.5 | Jun 2011 | EP | regional |
