This invention relates generally to wet shaving systems and, more particularly, to a mechanism for delivering shaving aid material to a user's skin during a shaving operation.
Conventional shaving devices that simultaneously apply a shaving preparation and remove hair typically include a removable cartridge and a comfort strip having shaving preparation impregnated therein mounted on a skin-contacting surface of the cartridge. As the razor cartridge is stroked over a user's skin, the shaving aid material is released from the comfort strip onto the user's skin. A difficulty associated with the use of comfort strips is that there is insufficient shaving aid material contained therein to provide, for example, adequate lubricity to the user's skin when shaving large surface areas such as a person's legs.
Based on the foregoing, it is a general object of the present invention to provide a razor assembly usable in a wet shaving environment that is capable of providing a sustained, consistent release of shaving preparation material to a skin surface during a shaving operation that improves upon the prior art.
In one aspect, the present invention is directed to a wet shave razor assembly that includes a shaving aid delivery system surrounding a razor cartridge. The shaving aid delivery system includes a hydrophilic foam having a water soluble shaving preparation disposed therein. Preferably, the hydrophilic foam defines a central aperture extending at least part way through the hydrophilic foam surface. The central aperture is sized to receive the razor cartridge therein. During a wet shave operation, the hydrophilic foam is compressed as the razor is stroked across a user's skin. The compression of the foam in the wet-shave environment causes the shaving aid material disposed within the foam to be controllably released onto the user's skin. Preferably, the razor cartridge can pivot about an axis extending in a lengthwise direction of the razor cartridge. However, the present invention is not limited in this regard as the razor cartridge can also be non-pivotable. It is also preferable that the razor cartridge is movable relative to the hydrophilic foam to allow the foam to be sufficiently compressed to cause the shaving preparation to be dispensed. However, the present invention is not limited in this regard as the hydrophilic foam can also extend past the razor cartridge so that it must be compressed to allow the cutting edges of the razor blades to contact a user's skin during a shaving operation.
In another aspect, the hydrophilic foam is defined by a plurality of supporting elements in the form of walls or struts that cooperate to define tortuous paths. The shaving preparation is disposed in these tortuous paths. In the preferred embodiment of the present invention, the shaving preparation material is water-soluble. The hydrophilic foam pad can be produced as a hydrolyzed reaction product of a polyol, a polyoxyethylene diol, and an isocyante and such that shaving preparation material is incorporated into the foam. The hydrophilic foam can comprise open cells or closed cells, or it can be a combination of open cells and closed cells.
In another aspect, the present invention is directed to a shaving preparation delivery system defined by a foam pad having a central aperture and a contact surface and a water soluble shaving preparation material disposed in the foam pad. The foam pad can be a replacement pad that is mountable on one of a base forming part of a replacement cartridge and a handle. When the foam pad is mounted on either the razor cartridge or the handle, pressure exerted on the foam pad (e.g., by pressing or stroking the pad against the surface to be shaved in a shaving operation) causes the shaving preparation to be dispelled from the contact surface onto a user's skin.
The present invention can also be embodied in a cartridge/shaving aid delivery system assembly that can be releasably attached to a handle. Alternately, the shaving aid delivery system and the razor cartridge can each be separately and releasably attachable to a handle. In addition, where the razor cartridge is movable relative to the hydrophilic foam, the mechanism allowing such movement can be housed in the handle with the razor cartridge being releasably attachable to the mechanism.
One advantage of using the above-described hydrophilic foams for delivering shaving preparation is that a sustained release of shaving preparation material can be realized during a shaving operation. Because of the hydrophilic nature of the foam, the shaving preparation material incorporated therein can be controllably solubilized and released in response to the needs of the user during a shaving operation.
Another advantage of using the above-described hydrophilic foams is that the durability and dimensional stability of the foam structure allows for an extended number of shaves to be achieved without substantial degradation of the foam. More specifically, the material from which the foam is manufactured and the particular configuration of the cell structure of the foam allows the foam to maintain its structural integrity by, for example, inhibiting the collapse of the cell structure during use. By inhibiting collapse of the cells, shaving preparations (lubricants or the like) can be more efficiently and sufficiently expelled from the foam throughout the useful life of the device into which the foam is incorporated. The wear issues that are normally associated with soap-based shaving aid materials are also avoided.
Referring to
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The struts 14 impart structure to the foam 10. In particular, the struts 14 forming the tortuous paths 12 can be collapsed upon themselves to allow the foam 10 to be compressed. Upon compression of the foam 10 (e.g., by the application of pressure when pressing the foam onto the surface being shaved), the collapse of the struts 14 reduces the volume of void space defined by some or all of the tortuous paths 12. As the volumes of the void spaces are reduced, fluid in the void spaces is forced along the tortuous paths 12 to areas of lower pressure. In general, the area of lower pressure is the area adjacent the boundary surfaces 16 outside the foam 10. In the preferred embodiments, the fluid in the void space is a shaving preparation material.
The material from which the foam 10 is fabricated is preferably a hydrophilic polyurethane. The foam is derived from a prepolymer liquid resin prepared from low molecular weight polyols and polyoxyethylene diols with an isocyanate, particularly toluene diisocyanate. The resulting resin is an alcohol having two or more free isocyanate groups. The free isocyanate groups are hydrolyzed, thereby releasing carbon dioxide gas, which foams the resin. The hydrolysis reaction products react with unhydrolyzed isocyanate to form a second reaction product that cross links with itself and stabilizes the foam structure. Excess water molecules trapped in the struts 14 impart the hydrophilic properties to the foam.
Upon manufacture, the foam may be mounted to release paper for transport or for storage until the foam is ready to be incorporated into a razor assembly or other shaving device and/or loaded with shaving preparation material. The foam may be mounted to the release paper by dropping the foam onto the paper or by molding the foam directly to the paper. The release paper may be a woven or non-woven material. The tack quality of the foam, particularly immediately after its fabrication, is generally sufficient to allow the release paper to be adhered to the foam.
Referring now to
When used with a wet-shave razor, the foam 10 provides a mechanism that yields a sustained release of shaving preparation onto a user's skin over an extended number of shaves. In one embodiment, as shown in
In another embodiment, as shown in
Referring now to
The mechanisms for shaving preparation material transfer described with reference to
Referring now to
The foam 10 forming part of the shaving aid delivery system 71 includes the one or more shaving preparation materials (e.g., lubricants, drag reducing agents, depilatory agents, cleaning agents, fillers, medicaments, hair softeners, skin-conditioners, vitamins, biocides, pharmaceuticals, humectants, surfactants, and the like disposed therein) to enhance the shaving process. As is shown in
Referring to
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Although this invention has been shown and described with respect to the detailed embodiments thereof, it will be understood by those of skill in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the above detailed description, but that the invention will include all embodiments falling within the scope of the appended claims.
This application is entitled to the benefit of and incorporates by reference the disclosure of U.S. Provisional Patent Application Ser. No. 60/906,141 filed on Mar. 9, 2007. This application is related to U.S. Provisional Patent Application Ser. No. 60/906,110, filed on Mar. 9, 2007, the disclosure of which is incorporated by reference herein in its entirety.
Number | Date | Country | |
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60906141 | Mar 2007 | US | |
60906110 | Mar 2007 | US |