Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to shaving sticks, especially
shaving sticks which are transparent, resistant to rancidity,
provide c~cellent lubricity during shaving and/or rinse readily
from razor and skin.
The most widely used method of shaving hair on the skin,
e.g~ on legs, underarms and especially men's faces, involves
razor-shaving the lathered hair and skin. Lather used preparatory
to razor blade shaving performs two principal functions, namely,
to soften the hair e.g. the beard, for the purpose of reducing
the resistance offered the shaving blade and consequently the
distortion of the unsupported hair, and secondly to lubricate the
passage of the blade over the surface of the skin to minimize
razor drag with its increased tendency to produce skin ;rritation
and/or nicksJ cuts and abrasions of the skin.
The use of a shaving stick preparatory to razor blade
shaving performs essentially the same two principal functions,
and has a further advantage in eliminating the messy step of
applying the lather by hand rubbing or patting, or with a shaving
brush which must be rinsed and is subject to soap build up,
rancidity, and wear. A fully satisfactory shaving stick has however
not been readily produced and/or widely commercialized, being
subject to such deficiencies, disadvantages and problems as undue
softness or hardness, insufficient lubricity, unsatisfactory
post rinsibility from razor blade and/or skin, insufficient
softening of the hair, tendencies to liquify or to dry out and/or
to develop a rancid odor during storage and use, and the like.
It is an object of this invention to provide a shaving
stick, and a method of shaving therewith, which will not be subject
to one or more of the above deficiencies. Other objects and
i. ~
~ ~2-
advantages will appear as ~he descript:ion proceeds.
Ihc atta;nment of thc above objects is Made possible
by this invention which includes the provision of a preshave
assisting composi~ion in stick Eorm comprising, approximately
by weight;
I. 25 to 70% of g]ycerol monooleate
II. 8 to 25% of sodium stearate,
TII~ 0 to 50% of organic humectant, and
IV. l to 10% of water,
the ratio of I/II ranging from about 3/1 to about 5/1.
According to a preferred embodiment, the above composi-
tion contains about 10 to 30 wt. % of propylene glycol as
humectant. According to another preferred embodiment, the
composition further contains about 1 to lO wt. % of an ethoxameric
nonionic surfactant.
This invention also includes the provision of a method
comprising razor-shaving hair on the skin in the presence of the
above-defined compositions of this invention. Such method
typically comprises washing the face ~or other hair-carrying skin
portion of the body)~ as with soap and water, rinsing wi~h water,
rubbing the shaving stick uniformly on the wet hair and skin
to apply a thin film of the stick formulation thereon, and shaving
off the hair with a razor (blade). Desirably, the shaved portion
of the skin is then again rinsed with water.
The shaving sticks of this invention, whicn may of
course be provided in any convenient solid shape, size or surface
configuration, have been found to provide excellent lubricity,
to be substantially resistant to rancidity~ to have and maintain
the desired degree of solidity without softening, liquifying or
-3-
&~;
~rying out, to sat;sractorily softerl the hair fibers for ease
of cutting, to be readily rinsed with water -from ra~or blade and
skin, to be desirably transparent or translucent, and/or to leave
the shaved portion of the skin with a good feeling.
The essential glycerol monooleate (GMO) provides the
excellent lubricity properties attributable to the compositions
of this invention. Its use in "neat" form as a shaving aid
is however not practical because it is a soft semi-liquid mass
at ambient temperatures and is insufficien~ly water soluble, thus
making it messy and inconvenient to apply with the hand and
difficult to postrinse from razor and skin. U.S. 3,715,942
issued February 13, 1973 to Courtney describes shaving composi-
tions which optionally contain GMO as a "preferred liquid
nonionic surfactant" but these compositions are liquid and
suffer from the same deficiencies as "neat" GMO.
The GMO may be employed in substantially pure formJ
or as commercially available forms containing minor amounts,
e.g. less than about 5 w~. % of glycerol dioleates and/or
trioleates. A preferred commercially available form is marketed
as Atlas* G-3496 (ICI America, Inc.) containing, by weight,
80% of GMO, 10% of propylene glycol, 7% of POE (20) sorbitan
monolaurate (sorbitan monolaurate polyoxyethyleneted with 20
moles of ethyleneoxide) and 3% of water. Being a surfactant, the
GMO also provides wetting and similar surface active functions,
in addition to softening and emolliency.
lhe shaving sticks of this invention typically contain
about 20 to about 70, preferably about 30 to 60, wt. % of the
GMO.
The essential sodium stearate (soap) component II provides
* Trade Mark
','l.~f3~
the requ;red hardening or gelling functioll necessary to form
and maintaln the desired solld characteristics of the stlck. It
typically constitutes about 8 to 25, preferably about 8 to 20,
wt. % of the composition. This soap also provides wetting,
rinsing, and similar surface active functions. Other soaps have
been found to fail substantially to provide these functions in
sufficient degree.
The highly preferred component III organic humectant
aids in preventing drying out of the shaving stick, in addition
to providing solvent and skin-moisturizing functions. One or a
mixture of humectants, well known in the art, may be employed,
typically in proportions of about 10 to about 50, preferably
about 10 to about 30, wt. %. These humectants are typically
polyhydroxycompounds such as glycerol, sorbitol, ethylene,
propylene, butylene and hexylene glycols, 1, 1, l-trimethylol
propane, 2-methyl-2, 4-pentanediol, neopentyl glycol, poly-
ethylene and polypropylene glycols, polyoxyethylenated sorbitol
and glycerol (e.g. POE (26) glycerolether), and the like. Propylene
glycol is preferred, typically in proportions of about 10 to about
30 wt. %, and combinations thereof with POE glycerol ethers.
Water, in proportions of about 1 to about 10, preferably
about 2 to less than 8, wt. % is included in these compositions
primarily to help dissolve and/or liquify the sodium stearate
for homogeneous admixture with the remaining components of the
compositions.
Another preferred component of the shaving stick
formulations of this invention is one or a mixture of nonionic
surfactants, typically in proportions of about 1 to about 10,
preferably about 2 to about 8, wt. %. These surfactants are well
-5-
known materials and may be broadLy de-fined as water soluble products
derivcd from the condensatioll of a plurality of moles of a C2 3
alkylene oxide or equivalellt reacta-nt (hydrophilic in nature) with
a reactive hydrogen-conta;ning organic hydrophobic compound whlch
may be aliphatic, aromatic, alicyclic or heterocyclic. The length
of the hydrophilic polyoxyalkylene chain in the condensation
product derived from any particular hydrophobe can be readily
adjusted to provide the desired degree of water solubility and
balance between hydrophilic and hydrophobic or lipophilic elements
(HLB factor). Although propylene oxide may be employed as the alkylene
oxide reactant, ethylene oxide is most commonly employed, more
effective and preferred herein. These polyoxyethylene-containing
condensation products have been referred to as ethoxamers or ethoxameric
nonionic surfactants.
The precursor hydrophobe of the nonionic surfac~ant ~ay
contain from about 6, preferably from about 8, up to 50 or more
carbon atoms and at least one reactive hydrogen-containing moiety
as present for example in aliphatic a]cohols, alkyl phenols,
carboxylic acids, carboxylic acid amides, sulfonamides, amines, and
the like. As a general rule, at least about 4 moles of ethylene
oxide should be reacted per mole of hydrophobe, but up to 200 moles
of ethylene oxide may be so reacted depending on the hydrophobe,
desired water solubility, surface activity, emolliency, plasticity
and melting point, and the like. The nonionic surfactant should be
liquifiable, e.g. at elevated temperatures up to about 90C, to
facilitate processing of the composition into stick form.
Representative operative nonionic surfactants include
polyoxyethylene polyoxypropylene block polymers (Pluronics*) and
other types as disclosed for example in the portion of U.S. 4,1~10,641
* Trade Mark
-6-
i6
issued Febru"ry 20, 1979 to Ramachandral-l from line 3 to line ~3
of columll 2. As ~xemplary of specific nol-1ionic surfactants, men~ior
is made of dinonyl phenol + l5 e. o. ( 1 mole of dinonyl phenol
reacted with 15 moles of ethylene oxide), dodecyl mercaptan ~ 20
E.O., lauramide ~ l8 E.O., stearic acid ~ 20 E.O., tetradecyl amine
+ 34 E.O., dodecyl sulfonamide + 16 E.O., and myristyl alcohol
+ 20 E.O. Preferred are condensation products of one mole o-f an
alkanol, preferably straight chain and primary, of about 9 to 20,
especially lO to 18, carbon atoms with about lO to 40, especially
about 15 to 30, moles of ethylene oxide, for example PEC (23)
laurylether, and condensation products of one mole of a partial
fatty acid ester of a polyhydric alcohol with a similar number
of moles of ethylene oxide, for example P~E (20) sorbitan mono-
laurate. The nonionic ethoxameric surfactant component provides
improved wetting and post-rinsibility functions.
Other optional and conventional additives may be included
in small proportions preferably less than about lO wt. % such as
perfumes, preservatives, colorants, bacteriostats, antioxidants,
proteins, binders, opacifiers, sequestrants, emollients, skin
conditioners, fillers, whiteners and the like.
In preparing the shaving sticks of this invention, the
components are preferably mixed in any order, preferably at elevated
temperatures sufficient to liquify the sodium stearate, e.g. at
about 75 to about 95C.
The following examples are only illustrative of preferred
formulations according to this invention and are not to be regarded
as limitative. All amounts and proportions referred to herein
and in the appended claims are by weight un~ess otherwise indicated.
Shaving sticks made with these formulations conform to the desired
-7-
3~
objects hereof wi~il respect to solldi-ty cllaracteristics, lubricity,
non-rancidity, post-rillsibility and/or post-sk;n feeling and the like.
% Example 1 _
-
58.00 Glycerol Monooleate
18.00 Sodium stearate
20.00 Propylene glycol
4.00 Deionized water
100. 00
% Exam~ 2 _
55.00 Glycerol monooleate
15.00 Sodium stearate
20.00 Propylene glycol
3.00 Deionized water
7.00 PEG (23) lauryl ether
100. 00
% Example 3
__
77.65 Atlas G-3496
15.00 Sodium stearate 1)
4.00 Benzyl alcohol (
3.00 Deionized water
0.3_ Perfume
100. 00
% Example 4
37.60 Atlas G-3496
8.00 Sodium stearate
6.00 Deionized water
l0.00 Propylene glycol
37.60 POE (26) glycerol ether
0.35 Perfume (2)
0.20 Glydant
0.15 Methylparaben
0.10 Propylparaben
100. 00
% Example 5
61.65 Atlas G-3496
15.00 Sodium stearate
3.00 Deionized water
0.35 Perfume
20._ Propylene glycol
100.00
--8--
~--r
, . . .
% Exam~_6
__ _ ____.
58.20 Atlas G-3496
15.00 Sodium stearate
3.00 Deionized water
20.00 Propylene glycol
0.35 Perfume
0.20 Glydant
0.15 Methylparaben
0.10 Propylparaben
3.00 Ethylene glycol distearate
100. 00
(l) Aid against sloughing of stick formulation after wetting.
(2) Preservative, 55% dimethlol d;methyl hydantoin, Glyco Chemical
Co. Trade Mark
(3) Preservative
(4) Opacifierl emollient
This invention has been disclosed with respect to preEerred
embodiments~ and various modifications and variations ~hereof
obvious to those skilled in the art are to be included within
the spirit and purview of this application and the scope of the
appended claims.
_g_
