Note: Descriptions are shown in the official language in which they were submitted.
20535S7
S~VTNG SYSl'EM
Thi~ invention relates to shaving systems, and
more particularly to shaving systems of the wet shave
type.
~n shaving systems o~ the wet ~have type,
factors such a~ the ~rictional drag of the razor acros~
the skln, the ~orce neQd~d to sQver hair~, and
irritation of preexi~ting skin damage can create a
degree of ~having di~comfort. Discomfort, and other
problem~ accompanying w~t shaving systQms, can be
alleviated by thQ application of shaving aid~ to the
skin. Shaving aid~ may be applied prior to, during, or
after shaving. A numb~r o~ problem~ accompany the u~e
of pre- and post-applied shaving aids. Pre-applied-
shaving aids can evaporatQ or can be carried away fromthe ~it- of application by repeated ~trokQs of the
razor. Post-applied-shaving aid~ are not present on the
skin during shaving and thu~ their application may be to
late to prevent an unwanted affect. Both pre-applied
and post-applied ~having aids add additional steps to
the shaving process.
Proposals have been made to incorporats a
shaving aid e.g., lubricant, whisker softener, razor
cleanser, medicinal agcnt, cosmetic agent or combination
thereof, into a razor, e.g., by frictionally securing a
shaving aid ln a recQss on the razor, by incorporating a
shaving aid directly into one or more molded polymeric
CAS~: 7929
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components of the razor, by adhesively securing a shaving aid
composite to the razor, and by use of a mech~nical connection
between a shaving aid composite and the razor. A water-soluble
shaving aid, e.g. polyethylene oxide, has been mixed with
non-water-soluble material, e.g., a polystyrene polymer, to
form an insoluble polymer/soluble shaving aid composite. The
composite has been mounted on razor and shaving cartridge
structures, adjacent the shaving edge or edges, of single or
multiple blade shaving system. Upon exposure to water, the
water-soluble shaving aid leaches from the composite onto the
skin.
In accordance with one aspect of the invention, there
is provided a shaving unit that comprises at least one blade
and a shaving composite that has a surface for engaging the
user's skin adjacent the blade edge. The shaving unit may be
of a disposable cartridge type adapted for coupling to and
uncoupling from a razor handle or may be integral with a handle
so that the complete razor ie ~;r~rded as a unit when the
blade or blades become dulled the blade edge (or edges)
cooperate with skin engaging surfaces to define shaving
geometry. The skin-engaging surface includes a shaped shaving
aid composite that is a mixture of water insoluble matrix
material, an effective amount of shaving aid material, and an
effective amount of water-insoluble essential oil material, the
water-insoluble essential oil material being delivered from the
shaving aid composite concurrently with the delivery of the
water-leachable shaving aid material during shaving to apply at
least about one nanogram of the essential oil to the skin
surface per square centimetre of skin surface.
Preferably, the shaving aid composite is of
extrusion-oriented material, and comprises 20-40% by weight of
the matrix material, 40-75% by weight of the water-leachable
shaving aid material, and 2-20% by
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weight o~ the essential oil material. The shaving aid
composition may further include a release enhancing
agent ~elected from the group eonsisting of polyethylene
glycol, methoxypolyethylene glycol, methylcellulose, and
carboxypolymethylene.
Suitable water-insoluble matrix materials
inel~de, for example, polyethylene, polypropylene,
polystyrene and polyacetyl. Suitable shaving aid
material~ inelude, for exampl-, polyethylene oxide,
polyvinyl pyrrolidone, polyaerylamlde, hydroxypropyl
cellulosQ, polyvinyl imidazonline,
polyhydroxyethylmethacry~ate, ~ilicone copolymers,
suero~e ~tearate, vitamin E, panthenol and aloe.
Suitable essential oil material~ inelude menthol,
lS eugenol toil of elove), euealyptol (oil of eucalyptus
and oil of ca~eput), safrol (oil of sassafras~ and
methyl salicylate toil of wintergrQen).
In particular embodiment~, the shaving agent
CompositQ i~ a member of extrusion-oriented blend of
~polymerie materials that eontains water-soluble and
water-insoluble material~, the nature and relative
proportions of the water-soluble and water-insoluble
polymerie materials being such that the member has
adeguate meehanical ~trength, both a~ initially produeed
and after a significant amount of the water-soluble
material ha~ been leaehed out.
In aecordance with another aspQct, there i8
pro~ided a p~ooe~ for forming a shaped ~having aid
compo~ite for a shaving system of the wet ~have type
that include~ a matrix of water-in~oluble pol~merie
material, an effective amount Or water-leachable shaving
aid material, and an effectlve amount of water-
insoluble essential oil material, the process including
the ateps of forming a blend of the water-insoluble
polymerie material and the water-leachable ~having aid
material, addinq the water-insoluble essential oil
material in particulate to form to the blend at a
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te~peratur- of less than 100-C. to foru a mixture, and
~xtruding the mixturQ in lecs than one minute after the
essential oil material i~ added to form thQ shaped
shaving a$d composite.
Other features and advantages will be seen as
the following description of particular embodiments
progressQs, in con~unction with the drawings, in which:
Fig. 1 is a pe~e~-ive view of a razor unit
in accordance with the invention;
Fig. 2 is a s~ctional view takon along thQ
lin~ 2-2 of Fig. l; and
Fig. 3 is a pe~pe~ivQ ViQW of another razor
unit ln accordance with the lnvention.
Th~ shaving unit 10 shown in Figs. 1 and 2
lnclude~ basQ or platform member 12 molded of high
~ impact polys~y~ene that include~ integral coupling
groove structurQ 14 for attachment to a razor handle and
guard structure 16 that defines a transvQrsely extending
forward ~kin engaging ~urfac- 18. On tho upper surfacQ
of platform 12 are disposed steel leading blade 20
having a sharp2ned edge 22, ste~l ~ollowing blade 24
having sharpened edge 26, and aluminum ~pacer member 28
that maintaln~ blade~ 20 and 24 in spaced relation. Cap
m~mbor 30 i~ ~olded o~ high impact polystyrenQ and has
body portlon 32 that defines skin engaging surface 34
that QxtQnds transversQly between forwardly pro~ecting
end wall~ 36 and has a front edge 38 that is disposed
r~arwardly o~ blade Qdge 26. Integral rivet portions 40
extend downwardly from transv~rsQly extending body
portlon 32 and pas~ through hole~ in blade~ 20 and 24,
spacer 28, and platform 12 to secure cap 30, blades 20,
24 and spacQr 28 on platform 12. Adhesively affixed to
s~in engaging sur~ace 34 is shaving aid composite 42.
The shaving unit 50 ~hown in Fig. 3 i~ of the
type shown ln Jacob~on U.S. Patent 4,586,255 and
includes body 52 with front portion 5~ and rear portion
56. Re~iliently secured in body 52 are guard member 58,
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leading blade unit 60 and trailing blade unit 62. A shaving aid
composite in the form of elongated insert member 64 is frictionally
locked in opening 66 of rear portion 56.
The following examples show by way of illustration and not
by way of limitation practice of the invention.
Example 1
A blend is formed of about thirty-one percent by weight high
impact polystyrene; fifty percent by weight of a water soluble polymer
(specifically a mixture of sixty percent by weight Polyox* Coagulant
polyethylene oxide five million molecular weight and forty weight
percent Polyox* WSRN-750 polyethylene oxide -- 300,000 molecular
weight); nine percent by weight of water soluble polyethylene glycol
(4,500 molecular weight); and ten percent by weight of menthol. The
blend includes color dye and antioxidant additives in minor amounts.
The blend is extruded through a nineteen millimeter diameter screw
extruder. The menthol is fed into the mixture in small particulate
form (particles of about forty microns or less in size) and is mixed
with the other constituents and extruded with a residence time in the
extrusion system of less than one minute. The feed zone (input to the
barrel) is at a temperature of about 80~C, intermediate barrel
temperatures are about 130~C and 160~C and the die is at a temperature
of about 180~C. The barrel pressure is about 1,800 psi and the die
pressure is about 2,400 psi. An extruded strip member of cross
sectional shape indicated in Fig. 3 is formed. Members 64 are sliced
from the extruded strip and secured in openings 66 of shaving units
50. The resulting extruded member 64 is sturdy and has an attractive
appearance, and the resulting cartridge 50 possesses good overall
shaving performance.
Example 2
A blend is formed of about thirty-two percent by weight high
impact polystyrene; fifty-two percent by weight of a water soluble
* Trade-mark
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polymer (specifically a mixture of sixty percent by weight Polyox*
Coagulant polyethylene oxide five million molecular weight and forty
weight percent Polyox* WSRN-750 polyethylene oxide -- 300,000
molecular weight); nine percent by weight of water soluble
polyethylene glycol (4,500 molecular weight); and six percent by
weight of menthol. The blend includes color dye and antioxidant
additives in minor amounts. The blend is extruded through an
extruder. The menthol is fed into the mixture in small particulate
form (particles of fifty-one hundred microns in size) and is mixed
with the other constituents. The water-cooled feed zone (input to the
barrel) is at a temperature of about 17~C, intermediate barrel
temperatures are about 120~C and 160~ and the die is at a temperature
of about 160~C. The barrel pressure is about 2,700 psi and the die
pressure is about 1,900 psi. An extruded strip member of cross
sectional shape indicated in Fig. 3 is formed. Members 64 are sliced
from the extruded strip and secured in openings 66 of shaving units
50. The resulting extruded member 64 is sturdy and has an attractive
appearance, and the resulting cartridge 50 possesses good overall
shaving performance.
Example 3
A blend is formed of about thirty-one percent by weight high
impact polystyrene; fifty percent by weight of a water soluble
polyethylene oxide; nine percent by weight of water soluble
polyethylene glycol (4,500 molecular weight); and ten percent by
weight of menthol. The blend is extruded through an extruder. The
menthol is fed into the mixture in small particulate form and is mixed
with the other constituents and extruded with a residence time in the
extrusion system of less than one minute. The feed zone (input to the
barrel) is at a temperature of about 120~C, the barrel
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temperature is about 160~C. and the die is at a temperature of
about 160~C. An extruded strip member of cross sectional shape
indicated in Fig. 3 is formed. Members 64 are sliced from the
extruded strip and secured in openings 66 of shaving units 50.
The resulting extruded member 64 is sturdy and has an
attractive appearance, and the resulting cartridge 50 possesses
good overall shaving performance.
Ex~mple ~
A blend is formed of about twenty-seven percent by
weight high impact polystyrene; forty-five percent by weight of
water-soluble polyethylene oxide: eight percent by weight of
water-soluble polyethylene glycol (4,500 molecular weight); and
twenty percent by weight of menthol. The blend is extruded
through an extruder, and the menthol is fed into the mixture in
small particulate form and is mixed with the other constituents
and extruded with a residence time in the extrusion system of
less than one minute. The feed zone (input to the barrel) is
at a temperature of about 80~C., the barrel temperature is
about 160~C. and the die is at a temperature of about 180~C.
An extruded strip member of cross sectional shape indicated in
Fig. 3 is formed. Members 64 are sliced from the extruded
strip and secured in openings 66 of shaving units 50. The
resulting extruded member 64 is s~urdy and has an attractive
appearance, and the resulting cartridge 50 possesses good
overall shaving performance.
The water-insoluble menthol is dispersed from the
cartridge insert with the polyethylene oxide lubricant and
tends to reduce the level of irritation produced upon shaving
and to improve the overall comfort and quality of the shave.
The resulting quantity of the menthol in insert 64 is about
three percent, a portion of which is associated with the
polystyrene and about twenty percent of the original quantity
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of the menthol in the insert member remains with the
polystyrene residue after the polyethylene oxide and other
water-extractable materials have been completely leached from
insert 64.
The system delivers about fifteen nanograms of menthol
per square centimetre of the skin and about two-thirds of the
delivered menthol is substantive. Inserts 64 containing about
three percent menthol were shown to deliver about five
mi~,o~Lams of menthol to the face during shaving (as determined
by gas chromatography/mass spectrometry, analysis of alcohol
extracts of the skin surface). After rinsing, about two-thirds
of the delivered menthol; i.e., 3.3 micrograms, remained on the
skin.
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