EP3398736A1

EP3398736A1 - Blade unit for safety razor including lubrication and/or care pad, safety razor and method of manufacture

Info

Publication number: EP3398736A1
Application number: EP17168946.6A
Authority: EP
Inventors: Yvonne NEUMANN; Michaela Kohut; Jens Treu
Original assignee: Beiersdorf AG
Current assignee: Beiersdorf AG
Priority date: 2017-05-02
Filing date: 2017-05-02
Publication date: 2018-11-07

Abstract

The present invention relates to blade unit for a safety razor, comprising a blade housing comprising a plurality of blades, a guard in front of the cutting edges and a cap to the rear of the cutting edges, wherein the guard and the cap each comprise a pad for contacting the skin prior to or after shaving, respectively. According to the present invention, the guard pad comprises a skin preparation composition and the cap pad comprises a skin care composition which differs from the said skin preparation composition. Also part of the invention is a safety razor comprising the blade unit and a method of manufacture.

Description

FIELD OF THE INVENTION

The present invention relates to blade units for safety razors including pads for lubrication and/or care.

BACKGROUND OF THE INVENTION

Safety razors are typically composed of a blade unit, or cartridge, connected to an elongate handle extending essentially in the direction of shaving. Blade units are known which have one or more blades, often a plurality of parallel blades, with blade unit elements positioned in front of and behind (rear of) the cutting edge(s) in a shaving direction (referred to as a "guard" and a "cap", respectively). A shaving aid, such as a lubricating strip, is often incorporated in one or both of these blade unit elements to improve shaving performance and lubricating treatment of the user's skin.
After shaving, a user's skin may suffer from various drawbacks, such as dryness, irritation, rashes, stress, razor burn, itches, swellings, inflammation, or general discomfort. Such effects may be avoided by the use of shaving creams or foams prior to shaving and/or lubricating, disinfecting or skin care products after shaving. These products can be impractical to use, for example when shaving body parts such as arm pits, intimate area, or legs while taking a shower, or when time is short.

SHORT DESCRIPTION OF THE INVENTION

The present invention is defined in the appended claims.
In particular, the present invention is embodied by a blade unit for a safety razor, comprising a blade housing comprising a plurality of blades, a guard in front of the cutting edges and a cap to the rear of the cutting edges, wherein the guard and the cap each comprise a pad for contacting the skin prior to or after shaving, respectively. According to the present invention, the guard pad comprises a skin preparation composition and the cap pad comprises a skin care composition which differs from the said skin preparation composition.
Skin preparation compositions for use in the guard pad are known to the skilled person in the art. According to one embodiment of the present invention, the skin preparation composition may be selected from the group consisting of PEG, polyvinylpyrrolidone (PVP), polyquaternium, palmitamidopropyltrimonium chloride (N,N,N-trimethyl-3-[(1-oxohexadecyl)amino]chloride), soaps, surfactants, glycerine, gums, powders, urea, lactic acid or mixtures thereof, in combination with or in the absence of water.
Skin care compositions for use in the cap pad are known to the skilled person in the art. According to one embodiment of the present invention, the skin care composition is selected from the group consisting of emollients, moisturisers, vitamin E, aloe barbadensis, panthenol, glycyrrhiza inflata root extract (Licocalcone), pentylene glycol and 4-t-butylcyclohexanol (Symsitive), chamomile, eucerit, or mixtures thereof, in combination with or in the absence of water.
According to one embodiment of the present invention, the skin preparation composition and/or the said skin care composition is impregnated in a polymer matrix embedded in the guard and/or the cap of the blade unit, as the case may be. In this embodiment, the said matrix is forming the backbone of the respective pad. According to one embodiment, both the skin preparation composition and the said skin care composition are impregnated in polymer matrices embedded in the guard and the cap of the blade unit. According to these embodiments, the matrix may comprise a thermoplastic elastomer (TPE), polystyrene, or a mixture thereof. It was found that the use of TPEs or polystyrene allows the skin preparation composition and/or the skin care composition is released gradually on contact with water.
According to one embodiment of the present invention, the guard pad and/or the cap pad extends at least over a portion of the width of the blade unit, wherein the said width is defined as being parallel to the said plurality of blades. In one embodiment, both the guard and the cap pads extend at least over a portion of the width of the blade unit. In one further embodiment, the guard pad extends over the entire width of the blade unit, and the cap pad extends over a portion of the width of the blade unit. In a further embodiment, the guard pad extends over a portion of the width of the blade unit, and the cap pad extends over the entire width of the blade unit. In one further embodiment, both the guard pad and the cap pad extend over the entire width of the blade unit.
According to one embodiment of the present invention, the blade unit may be attached releasably to a handle to form a razor unit. This allows the blade unit according to the present invention to be replaced when either the guard or the cap have been depleted of one or more of their contents, or when the blades of the blade unit are no longer in satisfactory working order due to wear.
The present invention also concerns a safety razor comprising a blade unit according to the present invention. A safety razor according to the present invention may comprise a blade unit according to the present invention and a handle. For example, a blade unit according to the present invention may be releasably attached to the handle to form a safety razor according to the present invention.
Also part of the present invention is a method for manufacture of a blade unit according to the invention, comprising the steps of providing a blade housing comprising a plurality of blades, providing a guard in front of the cutting edges and a cap to the rear of the cutting edges, wherein the guard and the cap each comprise a pad for contacting the skin prior to or after shaving, respectively, and wherein the guard comprises a skin preparation composition and the cap comprises a skin care composition which differs from the said skin preparation composition.
The above indicated aspects and embodiments may be combined with each other to achieve the advantageous effects as described above. Further embodiments, features, and advantages of the invention, as well as the structure and operation of the various embodiments of the invention are described in detail below with reference to the accompanying drawings.

SHORT DESCRIPTION OF THE FIGURES

The invention will be further illustrated by reference to the following figures:

Fig. 1 represents a blade unit according to the present invention, wherein the guard pad and the cap pad both extend over a partial portion of the width of the blade unit;
Fig. 2 represents a blade unit according to the present invention, wherein the guard pad and the cap pad both extend over the entire width of the blade unit.

It is understood that the following description and references to the figures concern exemplary embodiments of the present invention and shall not be limiting the scope of the claims.

DETAILED DESCRIPTION OF THE INVENTION

The present invention according to the appended claims provides a blade unit for a safety razor comprising a guard and a cap, wherein the guard and the cap comprise compositions for skin preparation and skin care, respectively.
According to the present invention, a skin preparation composition comprised in the guard is released from the guard, and a skin care composition comprised in the cap is released from the cap during use of a razor unit comprising the blade unit of the present invention. The release of the skin preparation composition from the guard leads to the skin being prepared for shaving by the released skin preparation composition prior to contact with the blades and actual shaving. The release of the skin care composition from the cap leads to the skin being treated with a care agent after contact with the blades and shaving.
Both the skin preparation composition and the skin care composition fulfil functions intended to reduce skin irritation resulting from the shaving action.

Skin preparation compositions

According to the present invention, the said skin preparation compositions may be selected from the group consisting of PEG, polyvinylpyrrolidone (PVP), polyquaternium, palmitamidopropyltrimonium chloride (N,N,N-trimethyl-3-[(1-oxohexadecyl)amino]chloride), soaps, surfactants, glycerine, gums, powders, urea, lactic acid or mixtures thereof, in combination with or in the absence of water.
For example, the skin preparation composition may consist of or comprise PEG (polyethyelene glycol). PEG is a water soluble, thermoplastic polymer available in a broad range of molecular weights. In one embodiment, the PEG may be a mixture of different PEG classes, such as PEG-115M, PEG-45M, PEG5-M, PEG-100, or the like (INCI nomenclature), or the PEG may consist of a single PEG-class. The PEG (single class or mixture of classes) may be mixed with any of the other listed components of the skin preparation composition, or it may be the only component.
Alternatively or in addition, the skin preparation composition may consist of or comprise further polymers, such as for example polyvinylpyrrolidone (PVP) or polyquaternium (polyquaternium-10, polyquaternium-7, polyquaternium-68, or anyh other suitable polyquaternium). The further polymers may be a single one of the listed ones, or a mixture of suitable polymers.
Alternatively or in addition, the skin preparation composition may consist of or comprise palmitamidopropyltrimonium chloride (N,N,N-trimethyl-3-[(1-oxohexadecyl)amino]chloride), which is normally used as an antistatic agent or a hair conditioning agent.
Alternatively or in addition, the skin preparation composition may consist of or comprise soaps, such as for example sodium palmate, sodium stearate, sodium cocoate, surfactants, such as for example sodium laureth sulfate, sodium cocoyl isethionate, disodium cocoyl glutamate, or glycerine in pure or aqueous form. All these may be used as an exclusive component of the skin care composition or in combination with any other component or components listed herein.
Furthermore, the skin preparation composition may consist of or comprise other ingredients, such as gums (such as guar hydroxypropyltrimonium chloride, hydroxypropyl guar, chondrus crispus extract, carrageenan, hydroxypropyl methylcellulose, hydroxyethylcellulose, or xanthan gum), particulate components (such as talcum, kaolin, silica), and/or active agents such as urea, lactic acid or the like.
Any other skin preparation agents known to the skilled person may also be used as part of the skin preparation composition according to the present invention.

Skin care compositions

According to the present invention, the said skin care compositions may be selected from the group consisting of emollients, moisturisers, vitamin E, aloe barbadensis, panthenol, glycyrrhiza inflata root extract (Licocalcone), pentylene glycol and 4-t-butylcyclohexanol (Symsitive), chamomile, eucerit, or mixtures thereof, in combination with or in the absence of water.
As used herein, moisturisers or emollients are complex mixtures of chemical agents specifically designed to make the external layers of the skin softer and more pliable. Suitable compounds or compositions and known to the skilled person in the art. They increase the skin's water content, for example by reducing evaporation. Examples for use in the present invention may be selected from, but not limited to, almond oil, shea butter, glycerine, cetyl alcohol, cyclomethicone, grape seed oil, dimethicone, petrolatum, white petrolatum, (soft) paraffin wax, oilatum, balneum, medi oil, diprobase, or the like.
Alternatively or in addition, the skin care composition may consist of or comprise active agents intended to fulfil certain functions, depending on the needs of the user. These may be selected from but are not limited to vitamin E, panthenol, glycyrrhiza inflata root extract, pentylene glycol and 4-t-butylcyclohexanol, chamomile, eucerit, antioxidant agents such as tocopherol, anti-inflammatory agents such as aloe barbadensis leaf juice sunscreen compositions, or mixtures thereof.
Any of the above skin care agents may be used alone or in combination in the skin care composition.

Skin care compositions

According to one embodiment, the pad of the cap and/or the guard may comprise a matrix material for loading the skin preparation composition and/or the skin care composition, as the case may be. In one embodiment, both pads of the guard and the cap comprise a matrix material for loading the respective composition. This matrix material may be considered the backbone of the pad.
The said matrix material, or backbone, may adsorb the skin care composition or the skin preparation composition, such that the respective composition is released gradually during use, for example the respective composition may be released gradually when in contact with moisture. In some embodiments, the respective composition may be released gradually due to friction between the matrix material and the skin. In most embodiments however, the composition may be released gradually due to a combination of moisture action and friction action.
The said matrix material may be a polymer, such as for example a polystyrene or a thermoplastic elastomer (TPE). Materials which may be selected as the backbone structure are styrenic block copolymers and polystyrene, or combinations thereof.

Geometry

The pad in the cap and the pad in the guard may either extend over the whole width of the blade unit, or over a portion of the width of the blade unit. Two possible embodiments are represented in Figs. 1 and 2.
As shown in Fig. 1, both the guard pad comprising a skin preparation composition and the cap pad impregnated comprising a skin care composition extend over the full width of the blade unit, wherein the width is defined as the direction parallel to the shaving blades.
As shown in Fig. 2, both the guard pad comprising a skin preparation composition and the cap pad impregnated comprising a skin care composition extend over a partial portion only of the width of the blade unit.
Depending on the intended use of the blade unit, either embodiment may be preferred. For example, where the skin is particularly sensitive and the hair is relatively soft, it may be that less skin preparation and more skin care is required, such that it may be useful to have a smaller guard and a larger cap. On the other hand, where the skin is relatively robust and the hair to be removed is dense or thick, then more skin preparation and less skin care may be required. Any of these embodiments form part of the present invention.
The blade unit according to the present invention may be a replaceable blade unit which is releaseably attached to a handle to form a razor unit. Accordingly, the blade unit according to the invention may be replaced at any time when either of the pads in the guard and/or the cap has been depleted of its component(s), or when the blades are no longer in a satisfactory functioning condition.

Safety razors

Also comprised in the present invention is a safety razor comprising the blade unit according to the invention. Typically, a razor unit comprises at least a blade unit and a handle, wherein the blade unit may be releasably attached to the handle. Such razor units are known to the skilled person in the art.
According to the present invention, however, the razor units allow for skin preparation prior to shaving and skin care composition application after shaving.

Method of manufacture

Also comprised in the present invention is a method of manufacture of the blade units according to the invention. Embodiments of the present invention include a method of manufacturing a blade unit for a safety razor, comprising providing a blade housing comprising a plurality of blades, providing a guard in front of the cutting edges and a cap to the rear of the cutting edges, wherein the guard and the cap each comprise a pad for contacting the skin prior to or after shaving, respectively. According to the invention, the guard pad comprises a skin preparation composition and the cap pad comprises a skin care composition which differs from the said skin preparation composition.
It should be noted that the present invention may comprise any combination of the features and/or limitations referred to herein, except for combinations of such features which are mutually exclusive. The foregoing description is directed to particular embodiments of the present invention for the purpose of illustrating it. It will be apparent, however, to one skilled in the art, that many modifications and variations to the embodiments described herein are possible. All such modifications and variations are intended to be within the scope of the present invention, as defined in the appended claims.

Reference numbers

2: cap
4: guard
6: blades

Claims

A blade unit for a safety razor, comprising:
a blade housing comprising a plurality of blades (6); and

a guard (4) in front of the cutting edges and a cap (2) to the rear of the cutting edges;

wherein the guard (4) and the cap (2) each comprise a pad for contacting the skin prior to or after shaving, respectively,

characterised in that the guard pad comprises a skin preparation composition and

in that the cap pad comprises a skin care composition which differs from the said skin preparation composition.
A blade unit for a safety razor according to claim 1, wherein the said skin preparation composition is selected from PEG, polyvinylpyrrolidone (PVP), polyquaternium, palmitamidopropyltrimonium chloride (N,N,N-trimethyl-3-[(1-oxohexadecyl)amino]chloride), soaps, surfactants, glycerine, gums, powders, urea, lactic acid or mixtures thereof, in combination with or in the absence of water.
A blade unit for a safety razor according to claim 1 or 2, wherein the said skin care composition is selected from the group consisting of emollients, moisturisers, vitamin E, aloe barbadensis, panthenol, glycyrrhiza inflata root extract (Licocalcone), pentylene glycol and 4-t-butylcyclohexanol (Symsitive), chamomile, eucerit, or mixtures thereof, in combination with or in the absence of water.
A blade unit for a safety razor according to any one of the previous claims, wherein the said skin preparation composition and/or the said skin care composition is impregnated in a matrix embedded in the guard and/or the cap, respectively.
A blade unit for a safety razor according to claim 4, wherein the said matrix is a polymer matrix which may comprise a thermoplastic elastomer, polystyrene, or a mixture thereof.
A blade unit for a safety razor according to any one of the previous claims, wherein the said guard pad and/or the said cap pad extends at least over a portion of the width of the blade unit, wherein the said width is defined as being parallel to the said plurality of blades.
A blade unit for a safety razor according to claim 6, wherein the said guard pad and/or the said cap pad extends over the entire width of the blade unit.
A blade unit for a safety razor according to any one of the previous claims, which is a replaceable blade unit for releasable attachment to a handle.
A safety razor comprising a blade unit according to any one of the previous claims.
A method of manufacturing a blade unit of any one of claims 1 to 8, comprising the steps of
providing a blade housing comprising a plurality of blades (6);

providing a guard (4) in front of the cutting edges and a cap (2) to the rear of the cutting edges;

wherein the guard (4) and the cap (2) each comprise a pad for contacting the skin prior to or after shaving, respectively,

characterised in that the guard pad comprises a skin preparation composition and

in that the cap pad comprises a skin care composition which differs from the said skin preparation composition.