U.S. patent number RE33,429 [Application Number 07/305,667] was granted by the patent office on 1990-11-06 for lattice-entrapped emollient-moisturizer composition.
This patent grant is currently assigned to Dow Corning Corporation. Invention is credited to Eric S. Abrutyn.
United States Patent |
RE33,429 |
Abrutyn |
November 6, 1990 |
Lattice-entrapped emollient-moisturizer composition
Abstract
This invention relates to solid emollient-moisturizer
compositions, and in particular relates to compositions wherein an
emollient-moisturizer is entrapped in the lattice of the
cross-linked polymer during in situ polymerization of the monomers
forming the polymer lattice. The invention provides for conversion
of solid and/or liquid emollients or moisturizers into solid,
free-flowing forms by entrapment of the functional materials in a
hydrophobic polymer lattice.
Inventors: |
Abrutyn; Eric S. (Middletown,
NY) |
Assignee: |
Dow Corning Corporation
(Midland, MI)
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Family
ID: |
27399954 |
Appl.
No.: |
07/305,667 |
Filed: |
February 3, 1989 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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246663 |
Mar 23, 1987 |
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Reissue of: |
683603 |
Dec 12, 1984 |
04724240 |
Feb 9, 1988 |
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Current U.S.
Class: |
424/480; 424/59;
424/60; 424/63; 424/64; 424/65; 424/68; 424/69; 424/DIG.10;
424/DIG.5; 510/142; 510/152; 510/441 |
Current CPC
Class: |
A61K
8/36 (20130101); A61K 8/361 (20130101); A61K
8/362 (20130101); A61K 8/37 (20130101); A61K
8/8152 (20130101); A61K 8/86 (20130101); A61K
8/925 (20130101); A61Q 13/00 (20130101); A61Q
15/00 (20130101); A61Q 19/10 (20130101); A61K
2800/56 (20130101) |
Current International
Class: |
A61K
8/37 (20060101); A61K 8/72 (20060101); A61K
8/36 (20060101); A61K 8/92 (20060101); A61K
8/30 (20060101); A61K 8/81 (20060101); A61K
8/86 (20060101); A61Q 19/10 (20060101); A61Q
13/00 (20060101); A61Q 15/00 (20060101); A61K
007/00 (); A61K 007/46 (); A61K 007/48 () |
Field of
Search: |
;514/847 ;424/DIG.5 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1099429 |
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Apr 1981 |
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CA |
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26085336 |
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Sep 1976 |
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DE |
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2815139 |
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Oct 1978 |
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DE |
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336495 |
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Nov 1973 |
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GB |
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Other References
"Mineral Oil and Petrolatum; Reliable Moisturizers," Tranner et al,
Cosmetics & Toiletries, vol. 93. .
Bakan, Microencapsulation as applied to Pharmaceutical Products,
10/1968, pp. 11-14 and 20. .
National Cash Register Co., Microencapsulation, 1967, p. 436, 453
to 455. .
M. G. deNavarre, The Chemistry and Manufacture of Cosmetics, vol.
3, 2nd ed., 1975, Chapter 9. .
"Moisturization; A Systematic Approach"-L. J. Murphy-Cosmetics
& Toiletries, 3/1978, vol. 93, p. 31..
|
Primary Examiner: Ore; Dale R.
Attorney, Agent or Firm: DeCesare; Jim L.
Parent Case Text
RELATED APPLICATION
This application is a continuation-in-part of my copending
application Ser. No. 246,663, filed Mar. 23, 1981, entitled
"Polymer Entrapped Emollient-Moisturizer Composition", now
abandoned.
Claims
What is claimed is:
1. .[.A.]. .Iadd.In a cosmetic or toiletry composition, the
improvement which comprises a .Iaddend.solid, lattice-entrapped
emollient or moisturizer composition comprising:
from approximately 5% to approximately 95% by weight of a
cross-linked syneresis-free hydrophobic polymer lattice;
from approximately 95% to about 5% by weight of an emollient or
moisturizer;
the monomers of said cross-linked copolymer and said emollient or
moisturizer being polymerized in situ; and
said emollient or moisturizer being dispersed uniformly throughout
and entrapped within said polymer lattice.
2. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein said emollient or moisturizer is
selected from the group consisting of:
a straight, branched or cyclic hydroxyl alcohol containing 1 to 30
carbon atoms;
a straight, branched or cyclic carboxylic acid containing 1 to 30
carbon atoms;
an acid ester containing C.sub.1 to C.sub.30 carboxylic acid
esterified with a C.sub.1 to C.sub.30 hydroxyl alcohol; and
a hydroxy alcohol ether containing 1 to 30 carbon atoms;
a carboxylic acid ether containing 1 to 30 carbon atoms;
an alkane of the formula H--(CH.sub.2).sub.n --H wherein n is 5 to
30;
lanolin and its derivatives.
3. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein said cross-linked polymer matrix
comprises:
a functional cross-linking monomer selected from the group
consisting of di- or polyfunctional monomers having at least two
polymerizable double bonds; and
a monofunctional monomer selected from the group consisting of
polymerizable monomers having one double bond.
4. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 3, wherein said polyfunctional cross-linking
monomer is a poly-unsaturated monomer selected from the group
consisting of a mono- or or di- or polyester of mono-, di-, or
polyvalent alcohol, and alpha-beta unsaturated carboxylic acid,
polyunsaturated polyvinyl ether of a polyvalent alcohol, mono- or
polyunsaturated amides and cycloaliphatic esters of alpha-beta
unsaturated carboxylic acids.
5. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 3, wherein said monofunctional monomer is
selected from the group consisting of hydrophobic and hydrophylic
monounsaturated monomers.
6. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, including a fragrance in the amount of about
10% to about 90% by weight of said emollient or moisturizer.
7. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, including an oil soluble cosmetic dye in an
amount of about 0.1% to about 10% by weight of said emollient
and/or moisturizer.
8. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, including a cosmetic pigment in an amount of
about 0.1% to about 10% by weight of said emollient and/or
moisturizer.
9. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein said emollient or moisturizer is
2-ethylhexyl hydroxystearate which is entrapped in said polymer
lattice.
10. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein said emollient or moisturizer is
mineral oil.
11. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein arachidyl propionate is entrapped in
said polymer lattice.
12. A .[.lattice-entrapped emollient or moisturizer.]. composition
as claimed in claim 1, wherein said functional material is a
siloxane.
13. A .[.lattice-entrapped.]. composition as claimed in claim 1,
wherein a siloxane selected from the group consisting of
polydimethyl siloxane, polytrimethyl siloxane, polyhexamethyl
siloxane and polyphenylmethyl siloxane is entrapped in said polymer
lattice.
14. .[.A.]. .Iadd.In a cosmetic or toiletry composition, the
improvement which comprises a .Iaddend.solid, lattice-entrapped
cosmetic composition comprising:
from approximately 5% to approximately 95% by weight of a
cross-linked syneresis-free hydrophobic polymer lattice;
from approximately 95% to about 5% by weight of a cosmetic
substance;
the monomers of said cross-linked copolymer and said cosmetic
substance being polymerized in situ; and
said cosmetic substance being entrapped and dispersed throughout
and within said polymer lattice, said cosmetic substance comprising
at least one emollient or moisturizer selected from the group
consisting of:
a straight, branched or cyclic hydroxyl alcohol containing 1 to 30
carbon atoms;
a straight, branched or cyclic carboxylic acid containing 1 to 30
carbon atoms;
an acid ester containing C.sub.1 to CH.sub.30 carboxylic acid
esterified with a C.sub.1 to C.sub.30 hydroxyl alcohol;
a hydroxyl alcohol ether containing 1 to 30 carbon atoms;
a carboxylic acid ether containing 1 to 30 carbon atoms;
an alkane of the formula H--(CH.sub.2).sub.n --H wherein n is 5 to
30 lanolin and its derivatives and a siloxane selected from the
group consisting of hexamethyl disiloxane, cyclic polydimethyl
siloxane, linear polydimethyl siloxane, poly phenylmethyl siloxane
and polytrimethyl siloxane.
15. The .[.lattice-entrapped.]. composition as claimed in claim 14
wherein said emollient and/or moisturizer are releasable from
entrapment by pressure or extraction.
16. The .[.lattice-entrapped.]. composition as claimed in claim 14
wherein said emollient and/or moisturizer are releasable from
entrapment by diffusion as a result of temperature and humidity
changes. .Iadd.
17. In a cosmetic or toiletry composition selected from the group
consisting of pressed powders, toilet soaps, body powders, and
antiperspirant sticks, containing an emollient or moisturizer, the
improvement which comprises a solid, lattice-entrapped emollient or
moisturizer composition comprising: from approximately 5% to
approximately 95% by weight of a cross-linked syneresis-free
hydrophobic polymer lattice; from approximately 95% to about 5% by
weight of an emollient or moisturizer; the monomers of said
cross-linked copolymer and said emollient or moisturizer being
polymerized in situ; and said emollient or moisturizer being
dispersed uniformly throughout and entrapped within said polymer
lattice. .Iaddend.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
This invention relates to solid emollient-moisturizer compositions,
and in particular relates to compositions wherein an
emollient-moisturizer is entrapped in the lattice of a cross-linked
polymer during in situ polymerization of the monomers forming the
polymer lattice.
The art is replete with attempts to render functional materials
such as emollient-moisturizers amenable to release on demand
through encapsulation. Encapsulation confines materials in discrete
units or capsules as the result of coating particles of the
material with an encapsulant. The coating wall or encapsulating
material used in encapsulation includes natural or synthetic
polymers which permit release of the functional material by
fracture, degradation or diffusion.
It is an object of the present invention to provide a novel form of
entrappment of the functional material which does not encapsulate
the functional material.
This invention provides a unique combination of polymers and
functional materials, which results in compositions wherein the
functional materials rather than being encapsulated by coating
materials are dispensed throughout and entrapped within a polymeric
lattice. These compositions are useful for incorporating a variety
of functional materials, particularly emollients and moisturizers,
into a variety of products such as cosmetics and healthcare
products. Furthermore, the amount of functional materials which can
be entrapped in the lattice are much higher than heretofore
achievable by encapsulation.
BRIEF DESCRIPTION OF THE DRAWINGS
A better understanding of the present invention will become more
apparent from the following detailed description of the invention
taken in conjunction with the formal drawings, wherein:
FIGS. 1A-1D are photomicrographs at increasing powers of
magnification of an emollient ester entrapped in a polymer
lattice.
FIGS. 2A-2D show the visual effect at various degrees of
magnification of a lattice-entrapped functional material product
when it is applied in a thin layer.
FIGS. 3A-3D are photomicrographs of lattice-entrapped functional
material products wherein the functional material is a fragrance
which is homogeneously misable with the polymer.
FIGS. 4A-4C are photomicrographs of a lattice-entrapped emollient;
a lattice wherein the emollient has been extracted, and a polymer
which is formed without functional material in the polymer
lattice.
DESCRIPTION OF THE INVENTION
This invention relates to a solid, lattice-entrapped
emollient-moisturizer composition which comprises from about 5% to
about 95% by weight of a cross-linked polymer lattice and from
about 95% to about 5% by weight of an emollient-moisturizer
selected from the group consisting of a straight, branched or
cyclic alcohol containing 1 to 30 carbon atoms, a straight,
branched or cyclic carboxylic acid containing 1 to 30 carbon atoms,
an acid ester containing a C.sub.1 to C.sub.30 carboxylic acid
esterified with a C.sub.1 to C.sub.30 hydroxyl alcohol, a hydroxyl
alcohol ether containing 1 to 30 carbon atoms, a carboxylic acid
ether containing 1 to 30 carbon atoms, and an alkane of the formula
H--(CH.sub.2).sub.n --H wherein n is an integer of from about 5 to
about 30, and a siloxane. Unlike known methods of entrapping the
emollient-moisturizer by encapsulating the emollient-moisturizer,
the present invention entraps the emollient-moisturizer directly
within the polymer lattice during in situ polymerization of the
monomers.
It has now been discovered that a wide variety of materials
commonly referred to as emollients or moisturizers which are either
liquids or solids can be converted to free-flowing powders or beads
by entrapment of the materials in a hydrophobic polymeric lattice.
The entrapped materials are not themselves encapsulated in any way,
i.e. enclosed by capsules, coatings or sacs; rather, they are
dispersed throughout and entrapped within the polymeric lattice.
Such lattice-entrapped products have properties that are superior
to the encapsulated products of the prior art. The polymer lattice
functions to hold and protect the entrapped material without
encapsulating it, probably through sorption or swelling, and the
lattice is capable of making the material available by a variety of
mechanisms including pressure, diffusion and extraction.
Significantly, when the lattice-entrapped materials of this
invention are incorporated into cosmetic and toiletry products the
polymeric lattice itself contributes beneficial effects to the
product structure.
While this invention relates primarily to in situ lattice
entrapment of emollient-moisturizers within the polymeric lattice,
those skilled in the art will recognize that a wide variety of
functional materials can be entrapped within the polymeric lattice.
The invention contemplates that a wide variety of water insoluble
organic liquids and solids may be incorporated within the lattice.
In face, any functional material which will not chemically react
with the polymer system comprising the polymeric lattice can be
entrapped with the polymeric lattice.
The application will discuss the invention as it relates
specifically to emollient-moisturizer lattice-entrapped products.
The terms "emollient" and "moisturizer" include materials having
properties defined for those terms in the text and articles:
M. G. de Navarre, The Chemistry and Manufacture of Cosmetics, Vol.
3, 2nd Ed. 1975, Chapter 9.
"Moisturization; A Systematic Approach"--L. J. Murphy Cosmetics and
Toiletries, Vol. 93 (March, 1978) p. 31.
"Mineral Oil and Petrolatum; Reliable Moisturizers" by F. Tranner
and G. Berube--Cosmetics and Toiletries, Vol. 93, (March, 1978) p.
81.
The solid lattice-entrapped i.e., nonencapsulated,
emollient-moisturizer compositions of this invention are prepared
by combining in one step a functional crosslinking monomer, a
monofunctional monomer and the functional material to be entrapped
within the lattice under such conditions as to thereafter initiate
polymerization. As used herein, the term "functional crosslinking
monomer" is meant to include di- or polyfunctional monomers having
two or more polymerizable double bonds, while the term
"monofunctional monomer" is meant to include a polymerizable
monomer having one double bond. Functional crosslinking monomers
useful in the invention may be a polyunsaturated monomer selected
from the group consisting of a mono- or diester of an alcohol and
an alpha-beta unsaturated carboxylic acid; polyunsaturated
polyvinyl ether of a polyhydroxy alcohol; mono- or poly unsaturated
amides and cycloaliphatic esters of alpha-beta unsaturated
carboxylic acids. Examples of such functional cross-linking
monomers include polyethylene glycols having a molecular weight up
to about 5000 dimethacrylate, triethylene glycol dimethacrylate,
tetraethylene glycol dimethacrylate and trimethylol propane
ethoxylated triacrylate, available under the trademark CHEMLINK
176, ditrimethylol propane dimethacrylate; propylene, dipropylene
and higher propylen glycols having a molecular weight up to about
5000 including polyethylene glycol dimethacrylate, 1,3 butylene
glycol dimethacrylate, 1,4 butanediol dimethacrylate, 1,6
hexanediol dimethacrylate, neopentyl glycol dimethacrylate,
pentaerythritol dimethacrylate, dipentaerythritol dimethacrylate,
bisphenol A dimethacrylate, divinyl (trivinyl) benzene, divinyl
(trivinyl) toluene, triallyl maleate, triallyl phosphate, diallyl
maleate, diallyl itaconate, and allyl methacrylate.
The monofunctional monomer of the novel polymeric system of this
invention includes hydrophobic and hydrophilic monounsaturated
monomers. The monomers include alkyl methacrylates and acrylates
having straight or branched chain alkyl groups with 1 to 30 carbon
atoms, preferably 5 to 18 carbon atoms. Preferred monofunctional
monomer include lauryl methacrylate, 2-ethylhexyl methacrylate,
isodecylmethacrylate, stearyl methacrylate, hydroxy ethyl
methacrylate, hydroxy propyl methacrylate, diacetone acrylamide,
phenoxy ethyl methacrylate, tetrahydrofurfuryl methacrylate and
methoxy ethyl methacrylate.
The functional materials to be lattice-entrapped within the novel
polymeric lattice of this invention are selected from materials
commonly referred to as emollients and moisturizers, materials
which are normally either liquids or solids. Functional materials
such as perfumes, fragrances and flavors may be combined with
emollient-moisturizers and lattice-entrapped within the novel
polymeric lattice of this invention as well. Examples of emollients
and moisturizers whicy may be lattice-entrapped within the
polymeric lattice of this invention include straight, branched or
cyclic hydroxy compounds such as alcohols containing 1 to 30 carbon
atoms; straight, branched, or cyclic carboxylic acids containing 1
to 31 carbon atoms; acid esters containing C.sub.1 to C.sub.30
carboxylic acids esterified with C.sub.1 to C.sub.30 alcohols;
alcohol ether containing 1 to 30 carbon atoms; alkanes of the
formula H--(CH.sub.2)n--H, wherein n is 5 to 30; and siloxanes.
Examples of such functional materials include 2-ethylhexyl
oxystearate available commercially as WICKENOL .RTM.171; arachidyl
propionate available commercially as WAXENOL .RTM.801; 2-ethylhexyl
adipate available commercially as WICKENOL .RTM.158; isopropyl
myristate available commercially as WICKENOL .RTM.101; ethanol;
stearyl alcohol; propylene glycol; propionic acid; stearic acid;
polyoxypropylene cetyl alcohol, available commercially as WICKENOL
.RTM.707; polyoxypropylene lanolin alcohol available commercially
as WICKENOL .RTM.727; Carbowax .RTM.300; petroleum jelly; mineral
oil; aliphatic hydrocarbons such as mineral spirits; lanolin and
lanolin derivatives such as acetylated lanolin and isopropyl
lanolate; hexamethyl disiloxane, available commercially as DOW
.RTM.Q2-1096; cyclic polydimethyl siloxane, available commercially
as DOW .RTM.344 and 345; and linear polydimethyl siloxane,
available commercially as DOW .RTM.200; poly phenyl methyl
siloxane, available commercially as DOW .RTM.556; and poly
dimethyl/trimethyl siloxane. Other phenyl, ethyl and vinyl
substituted polysilanes may also be included in the products of
this invention.
The crosslinking monomer, monofunctional monomer and functional
material are combined in a ratio such that the resultant novel
lattice-entrapped composition of this invention comprises from
about 5% to about 95% by weight of a cross-linked polymer lattice
and from about 95% to about 5% by weight of the entrapped
functional material. The ratio of crosslinking monomer to
monofunctional monomer in the cross-linked polymer lattice can vary
within the range of 99:1 to 1:99. While not restricting the
invention to any precise composition, in a typical product of this
invention, the crosslinking monomer, monofunctional monomer and
functional material are combined in a ratio such that the resultant
novel cross-linked polymer lattice comprises from about 60 to about
80% by weight of the functional monomer entrapped therein.
The cross-linked polymer lattice containing the entrapped
functional material results from the in situ polymerization of the
monomer mixture which already has the functional material to be
entrapped dissolved therein. Generally, this results simply from
mixing the crosslinking monomer and the monofunctional monomer,
dissolving the functional material in the combined monomers to form
a uniform mixture, and thereafter inducing polymerization.
Polymerization may be induced by conventional initiators such as
peroxides and the like, or by irridiation or redox systems.
Polymerization usually occurs as temperatures between about
0.degree. to 120.degree. C., preferably about 80.degree. C. The
time and temperature of polymerization may be varied in accordance
with the nature of the functional material, its concentration, and
the attributes of the desired entrapped system, but in all
instances, the polymerization occurs only after the monomers and
the functional material are combined.
The physical properties of the lattice-entrapped functional
materials may be influenced by several factors such as the precise
combination of crosslinking monomer and monofunctional monomer
selected, the ratio in which these two components are combined with
one another and with the functional material. Accordingly, the
lattice-entrapped materials of this invention which exist in the
form of discrete, free-flowing powders or beads may be hard and
have the ability to withstand rather substantial shearing, or the
powders or beads may be soft, in which form they disintegrate or
spread to form a uniform layer with minimal pressure. In general,
the greater the ratio of cross-linked polymer lattice to the
functional material, the harder the lattice-entrapped material. The
lattice-entrapped functional material range in particle size from
about 0.001 millimeters to about 3 millimeters.
A simple test has been developed to predict with reasonable
accuracy whether or not a particular combination of crosslinking
monomer, monofunctional monomer and functional material will
polymerize to form the lattice-entrapped functional material of
this invention. According to this test, approximately equal
quantities of crosslinking monomer, monofunctional monomer and
functional material are combined in a test tube and polymerized. If
the resultant polymerized product is turbid or cloudy, a
heterogenious macroporous structure has formed which is a positive
indication that the components tested can be combined in a ratio
such that subsequent polymerization will result in the products of
this invention. There are exceptions to this rule, in that certain
combinations of materials may result in the production of a clear
polymer. If, however, when the clear polymer is extracted from the
reaction mixture it is determined to be cloudy or turbid,
indicating a heterogeneous, macroporous structure, a positive test
has again occurred. After a positive test, i.e., an initial turbid
or cloudy appearance on polymerization of the test tube size
sample, further tests are conducted by varying the ratio of
monomers to functional material to determine those ranges in which
discrete particles, and not clumps or masses, are obtained on
polymerization. With the foregoing test in mind, and recognizing
the need to obtain discrete particles and not clumped or massed
polymers, it will be appreciated that those skilled in the art can
select appropriate cross-linking monomer, monofunctional monomers
and the ratio in which these materials are to be combined to obtain
the lattice-entrapped materials of this invention.
The novel lattice-entrapped functional materials of this invention
are versatile products having application in many and varied types
of products. As stated previously, liquid and solid emollients and
moisturizers form lattice-entrapped products which are suitable for
incorporation in a wide variety of cosmetic, beauty and healthcared
products. Insecticides, disinfectants, sun screens, flavors,
pigments and perfumes may also be used as functional materials in
the lattice-entrapped materials of this invention.
A primary advantage of formation of the novel lattice-entrapped
functional materials of this invention is the conversion of liquid
or solid emollients and moisturizers into powdery, free-flowing
materials through incorporation in a syneresis-free hydrophobic
polymeric lattice. The lattice entrapment of the functional
material provides the ability to hold the functional materials for
controlled application on demand. Other advantages of the
lattice-entrapping the functional materials of this invention
include the ability to convert the solid and liquid functional
materials into free-flowing discrete particles ranging in size from
fine powders to rather large beads. Still another advantage of this
invention lies in the fact that the polymer lattice itself
contributes desirable attributes (discussed hereinafter) when the
functional materials are entrapped therein in the preparation of
cosmetics and toiletries.
The lattice-entrapped functional materials of this invention are
easy to handle, convenient to store, and are prepared by relatively
non-complex procedures. Lattice-entrapment of the functional
materials within the cross-linked polymer lattice protects the
functional materials from the environment, excessive
volatilization, and from ultraviolet light. The lattice-entrapped
functional materials are releasable from their entrapped state
within the microscopic lattice by the application of pressure, by
extraction and diffuse from the entrapped state due to temperature
and humidity changes. Also, it has been found that the desirable
characteristics of the lattice-entrapped functional materials, i.e.
emollients and moisturizers, are enhanced by the polymer lattice
itself. The polymer lattice provides a continuous film when applied
to the skin, so that the ultimate effect of the
lattice-encapsulation of this invention is to extend the
emollient-moisturizer effect of the lattice-entrapped
materials.
A decided advantage to be obtained by entrapping the functional
materials according to this invention results from being able to
incorporate substantially greater amounts of functional material in
a desired product than is possible through incorporation of the raw
functional material without lattice entrappment. For example, it is
known that an emollient such as 2 ethyl hexyl oxystearate (WICKENOL
.RTM.171) provides improved moisturizing and skin softening
qualities to toilet soap, but it is not possible to incorporate
more than about 2-5% of such an emollient in conventional toilet
soap formulations without seriously detracting from the foaming
characteristics of the soap. If, however, the emollient is first
formulated in the lattice-entrapped microscopic polymeric lattice
of this invention, substantially higher concentrations of the
emollient, up to as much as 20% by weight thereof, may be
incorporated into the toilet soap formulation, thereby serving to
enhance the softing and moisturizing properties of the soap without
any deleterious effect on the foaming and esthetic properties of
the soap. The polymer portion of the lattice also improves the
mechanical properties of the soap.
Another important application for the novel lattice-entrapped
functional materials of this invention is in the area of molded wax
and/or oil base sticks of the type typically used for
antiperspirants, deodorants, lipsticks, sun screens, insect
repellents and colognes. Typically, these stick-type products must
balance many ingredients in order to obtain the desired appearance
and function, but the optimal solid wax-oil base stick seems to
elude cosmetic formulators because of problems such as shrinkage,
variable rate of deposition on the skin, tackiness, and the like,
which continue to plague such products. The lattice-entrapped
functional materials of this invention offer significant advantages
to such stick-type products since they make it possible to
substantially reduce the bodying agents (such as natural, vegetable
or insect waxes) typically present in such stick products. These
advantages result from the fact that the polymeric lattice which
entraps the functional material enhances rigidity and strength of
the stick while it permits the lattice-entrapped functional
materials to produce their desired effect at they are made
available from their lattice-entrapped state.
The lattice-entrapped functional materials of this invention are
free flowing powders which are easy to handle and convenient to
store. The lattice-entrapped functional materials are made
available or released when applied to the skin either directly or
as a component of a cosmetic or toiletry product. It is thought
that when the entrapped functional material is applied to the body
in a cosmetic or toiletry product it is released as the result of
rubbing and spreading in the form of a continuous uniform film
protected within a hydrophobic envelope.
A scanning electron microscope (SEM) study was undertaken to better
understood how the functional materials are entrapped in the
polymer lattice. An objective of the study was to determine how
miscible and immiscible functional materials differ in the manner
in which they are incorporated into the polymer lattice.
Additionally, the investigation showed a comparison of the
lattice-entrapped product before and after a simulated
application.
FIGS. 1A-1D are photomicrographs of 2-ethyl hexyl
oxystearate/polymer powder (POLYTRAP .RTM.171) entrapped in a
polymer powder. The photomicrographs were taken at X20 (FIG. 1A),
X360 (FIG. 1B), X940 (FIG. 1C), and X3000 (FIG. 1D) power. The
photographs indicate that emollient ester is heterogeneously
adsorbed on the surface of a very fine polymer microdispersion
(cluster) of less than two microns in diameter. In the higher power
magnifications, it can be seen that rather than being encapsulated
by the polymer, the functional material is entrapped within the
polymer lattice.
FIGS. 2A-2D show examples of a lattice-entrapped functional
material product when the product is applied and spread out, such
as when it is applied directly to the skin. In this series of
photographs, the material is again POLYTRAP 171. FIG. 2A is an
untouched photograph of the lattice-entrapped product. FIG. 2B (at
X1000) shows the lattice-entrapped film material product after it
has been lightly spread. FIG. 2C (at X1000) shows the
lattice-entrapped film material product after it has been
completely spread and further shows that a continuous film material
results. FIG. 2D (at X15,000) shows a more magnified view of the
same product material as FIG. 2C. It can be seen from FIG. 2D that
the film consists of small (less than 2 microns) particles.
FIGS. 3A-3D are photomicrographs of the lattice-entrapped
functional material product which show the incorporation of a
fragrance as the lattice-entrapped functional material. Herein, the
fragrance is in the form of POLYTRAP Fragrance Polymer Beads. The
various photographs are taken at increasing powers of
magnification, X540 (FIG. 3A), X2000 (FIG. 3B), X3000 (FIG. 3C),
and X10,000 (FIG. 3D). The fragrance is homogeneously miscible with
the polymer, and is therefore very evenly dispersed within the
polymer lattice. This can be readily seen by comparing FIG. 3C
taken at X3,000 with the FIG. 1D which is a picture taken at the
same magnification, but with the immiscible functional material in
the polymer lattice. When the fragrance is homogeneously miscible
with the polymer, it can be seen that an almost featureless smooth
surface is created.
FIG. 4A shows a lattice-entrapped functional material product
according to the present invention (POLYTRAP .RTM.171) at a power
of X3,000. The same product is shown in FIG. 4B; however, the
lattice-entrapped emollient has been extracted therefrom. FIG. 4C
is a product formed without a functional material (POLYTRAP
.RTM.235) and consits simply of the blank polymer beads. FIGS. 4B
and 4C are very similar.
These various scanning electron microscopy studies of the
lattice-entrappment system of the invention show the effect of an
entrapped species on the physical characteristics of the polymer
formation. Moreover, the photographs indicate that the functional
material is entrapped within the polymer lattice rather than being
encapsulated by the polymer. When the functional material is
miscible (e.g. fragrance) in the polymer, a homogeneous polymer
lattice is formed which produces mechanically tough spheres or
beads which can be milled without disturbing the integrity of the
structure. When the material is a non-solvent for the polymer, a
heterogeneous internal structure is formed.
The cluster of beads formed by either the miscible or immiscible
functional material is fragile and when mechanical stress is
applied thereto, the clusters will fracture and produce a
continuous film of particle sizes less than two microns, even in
the range approaching 0.1-0.2 microns.
While it will be appreciated by those skilled in the art that there
are many variations in procedure and components, this invention may
be illustrated by the following examples:
EXAMPLE 1
7 grams of 2 ethylhexyl oxystearate (WICKENOL .RTM.171) was mixed
with 1.5 grams of ethylene glycol dimethacrylate and 1.5 grams of
lauryl methacrylate in a glass test tube. The solution was
deaerated for five (5) minutes and 0.1 ml of t-butyl peroctoate was
added and mixed while heating to 80.degree. C. in an oil bath.
After 20 minutes, the contents solidified; and the mixture was
maintained at about 80.degree. C. for an additional hour to assure
full polymerization. A semi-soft, heterogeneous white opaque
polymer mass resulted containing the entrapped ester.
The following examples demonstrate initial screening of the
crosslinking monomer, monofunctional monomer and functional
material to determine whether or not the combination thereof will
form the novel lattice-entrapped products of the invention. In each
test the components were combined in a test tube and polymerization
initiated and completed. Formulation of an opaque polymer mass in
the test tube scale test indicated that the components could be
combined in large scale polymerization to form the entrapped
functional materials of this invention.
EXAMPLE 2
Following the procedure of Example 1, the crosslinking monomers
tetraethylene glycol dimethacrylate, trimethylol-propane
trimethylacrylate, trimethylol-propane ethoxy triacrylate, and
allyl methacrylate were polymerized in the presence of 70% by
weight 2-ethylhexyl oxystearate and 15% by weight lauryl
methacrylate. In each case a semi-soft, white opaque polymer mass
resulted, indicating suitability for formation of the
lattice-entrapped product of this invention.
EXAMPLE 3
Following the procedure of Example 1, test tube polymerization was
completed varying the types of monomer constituents and their
ratios, and the quantity and type of functional material to be
entrapped. In each instance, t-butyl peroctoate was used to
initiate polymerization at a constant level of 3% by weight, based
on the weight of the combined content of monomers and functional
material. The components, quantity and test tube results are set
forth in Table 1. The following abbreviations are used in Table
1:
______________________________________ TEGDM Tetraethylene glycol
dimethacrylate TMPTM Trimethyl propane trimethacrylate EGDM
Ethylene glycol dimethacrylate TPETM Trimethyiol propane ethoxylate
trimethacrylate LMA Lauryl methacrylate IMA Isodecyl methacrylate
HMA Hydroxyethyl methacrylate DAA Diacetone acrylamide PMA
Phenoxyethyl methacrylate MEMA Methoxy ethyl methacrylate
______________________________________
TABLE I
__________________________________________________________________________
Cross- Mono Test Linking Weight Functional Weight Material Weight
Appearance No. Monomer % Monomer % Entrapped % in Test Tube
__________________________________________________________________________
1 TEGDM 67.5 LMA 22.5 2 Ethylhexyl 10 Hard-powdery, stearate white
opaque (WICKENOL .RTM. 171) polymer mass 2 TMPTM 45 IMA 45
Arachidyl pro- 10 Semi-hard, pionate off-white (WAXENOL .RTM. 801)
opaque 3 TMPTM 12 IMA 3 Arachidyl pro- 85 Semi-soft, pionate
off-white (WAXENOL .RTM. 801) opaque 4 EGDM 18.7 SMA 6.3
Di(Ethylhexyl) 75 Semi-soft, adipate white opaque (WAXENOL .RTM.
158) 5 EGDM 30 HMA 10.3 Isopropyl 60 Semi-soft, Myristate white
opaque (WICKENOL .RTM. 101) 6 EGDM 30 LMA 10 Ethanol 60
Hard-powdery, white opaque 7 TEGDM 67.5 SMA 22.5 Stearyl alcohol 10
Very hard, white opaque 25 EGDM 45 LMA 45 Mineral 10 Hard powdery,
white spirits opaque 26 EGDM 18.8 LMA 6.2 Mineral 75 Semi-hard,
white spirits opaque 27 TEGDM 12.5 LMA 12.5 Lanolin 75 Semi-soft,
yellow opaque 28 EGDM 60 SMA 30 Poly-Hexa- 10 Very hard, white
methyl opaque disiloxane 29 EGDM 15 SMA 5 (Dow .RTM. Q2-1096) 80
Hard, powdery, white opaque 30 EGDM 60 LMA 30 Poly 10 Hard,
powdery, white dimethyl opaque (cyclic) siloxane 31 EGDM 22.5 LMA
7.5 (Dow .RTM. 344 & 345) 70 Hard, powdery, white opaque 32
EGDM 45 DAA 45 Poly 10 Very hard, white opaque Dimethyl(Lin-) ear)
Siloxane 33 EGDM 10 DAA 10 (Dow .RTM. 200) 80 Semi-hard, white
opaque 17 EGDM 60 DAA 30 Polyoxy propylene 10 Very hard, (30 moles
lanolin) white opaque 18 EGDM 15 DAA 5 (WICKENOL .RTM. 727) 80
Semi-soft, yellowish, opaque 19 TEGDM 67.5 LMA 22.5 Carbowax .RTM.
300 10 Hard and clear 20 TEGDM 13 LMA 7 80 Semi-soft, white opaque
21 TPETM 54 PMA 36 Mineral oil 10 Hard-powdery, white opaque 22
TPETM 15 PMA 15 Mineral oil 70 Semi-soft, white opaque 23 TMPTM 45
MEMA 45 Petroleum jelly 10 Semi-soft, white opaque 24 TMPTM 15 MEMA
5 Petroleum jelly 80 Semi-soft, white opaque 8 TEGDM 15 SMA 5
Stearyl 80 Hard-powdery alcohol white opaque 9 EGDM 67.5 DAA 22.5
Propylene 10 Very hard, off- glycol white opaque 10 EGDM 15 DAA 5
Propylene 80 Semi-soft, off- glycol white opaque 11 EGDM 60 LMA 30
Propionic 10 Very hard, acid white opaque 12 EGDM 15 LMA 5
Propionic 80 Semi-hard, acid white opaque 13 TEGDM 45 SMA 45
Stearic 10 Very hard, white acid opaque 14 TEGDM 10 SMA 10 Stearic
80 Semi-hard white acid opaque 15 EGDM 67.5 SMA 22.5 Polyoxy
propyl- 10 Very hard, white ene (30 moles) opaque 16 EGDM 15 SMA 5
cetyl alcohol 80 Semi-soft, white (WICKENOL .RTM. 707) opaque
__________________________________________________________________________
The following examples demonstrate formation of the
lattice-entrapped materials of this invention.
EXAMPLE 4
1.20 grams of polyvinyl pyrrolidone having a K value of about 80 to
100 and available from Dan River, Inc., was dissolved in 1500 ml of
water in a 2000 ml three necked resin flask equipped with a
stirrer, thermometer and nitrogen purge. A solution of 335 grams of
2 ethylhexyl oxystearate (WICKENOL .RTM.171), 132 grams ethylene
glycol dimethacrylate, 33 grams 2-ethylhexyl methacrylate and 5 ml
t-butyl peroctoate was bubbled with nitrogen for 5 minutes. The
resultant monomer mix was slowly added to the stirred aqueous
solution of polyvinyl pyrrolidone at 22.degree. C. under nitrogen.
The temperature was raised to 80.degree. C. with constant agitation
and held until polymerization started in approximately 15 minutes,
and maintained at 80.degree. C. for an additional 2 hours to
complete the reaction. Semi-soft, white opaque beads were collected
by filtering off the supernatant liquid and dried to remove any
excess water. The beads weighed 450 g for a yield of 90%, and were
0.25 to 0.5 mm in diameter. Other protective colloids such as
starch, polyvinyl alcohol, carboxymethyl cellulose, methyl
cellulose, or inorganic system such as divalent alkali metal
hydroxides, for example MgOH, may be used in place of the polyvinyl
pyrrolidone suspending medium.
EXAMPLE 5
The procedure of Example 4 was repeated except that in each case
337.5 g arachidyl propionate (WAXENOL .RTM.801), or 337.5 g mineral
oil, or 350 g cyclic polydimethyl siloxane (DOW .RTM.345), or 350 g
petroleum distillate (150.degree. to 160.degree. C. boiling point),
or 325 g petroleum jelly, or 350 g isopropyl isostearate (WICKENOL
.RTM.131) or 375 g. Di(2 ethylhexyl) adipate (WICKENOL .RTM.158),
were substituted for 2-ethylhexyl oxystearate. In each case,
semi-soft, white opaque beads were collected in good yield. These
beads may be incorporated into cosmetic or toiletry products where
they domonstrate their desired effect by making the
lattice-entrapped emollient-moisturizer available for application
to the skin. The particle size of the resultant bead in each case
was between 0.25 to 0.5 mm in diameter. The precise particle size
varied somewhat due to the degree and rate of agitation during
polymerization and the rates of the components to the water in
which the polymerization system was suspended.
The following examples demonstrate cosmetic or toiletry
compositions in which the lattice-entrapped functional materials of
this invention have been incorporated.
EXAMPLE 6
______________________________________ Translucent Pressed Powder
______________________________________ Talc 77.64 Kaolin 14.00 75%
Arachidyl- 5.00 propionate en- trapped bead of Example 5 Magnesium
carbonate 2.00 Colorants 0.31 Methyl paraben 0.10 Propyl paraben
0.10 Germail 115 0.10 Fragrance 0.75 100.00
______________________________________
The components were combined in accordance with conventional
formulation techniques. The lattice-entrapped emollients (Example 5
product) provided a pressed powder with desired emollient
properties and application of the product to the body made the
emollient available by rubbing. The pressed powder was remarkably
resistant to breakage crumbling and glazing.
EXAMPLE 7
______________________________________ Milled Toilet Soap
______________________________________ Toilet soap base of tallow
89.00 and coconut.sup.1 2-ethylhexyl oxystearate 10.00 entrapped
bead of Example 4 Fragrance 1.00 100.00
______________________________________ .sup.1 Duveen Soap
Corporation, 154 Morgan Avenue, Brooklyn, New York
The components were combined in accordance with conventional
formulation techniques. The lattice-entrapped emollient (Example 4)
provided the soap with the desired emollient properties. In
addition, the physical attributes of the soap were enhanced,
rendering it more resistant to cracking in use and less brittle.
The soap had excellent lathering properties.
EXAMPLE 8
______________________________________ Body Powder
______________________________________ Talc 84.5 Fragrance 0.5
2-ethylhexyl oxy- 10.0 stearate entrapped bead of Example 4 Syloid
#74 5.0 100.00 ______________________________________
The components were combined in accordance with conventional
formulation techniques. The lattice-entrapped emollient (Example 4)
provided the body powder with the desired emollient properties. In
addition, the physical properties of the body powder were enhanced
by providing increased adhesion to the body.
EXAMPLE 9
______________________________________ Antiperspirant Stick
______________________________________ Phase A Stearyl Alcohol 25.0
Synthetic Beeswax Flakes.sup.a 10.0 WAXENOL .RTM. 821 Myristyl
Myristate.sup.a 25.0 WAXENOL .RTM. 810 Propylene Glycol Stearate
25.0 Phase B Aluminum chlorhydrate.sup.a 25.0 WICKENOL .RTM. CPS
325 Phase C 2-Ethylhexyl oxystearate en- 5.0 trapped bead of
Example 4 Di-octyl adipate entrapped 5.00 bead of Example 5 100.00
______________________________________ .sup.a Wickham Products,
Inc., Hugenmot, New York 12746
The antiperspirant stick formulations were prepared by heating the
components of Phase A to 65.degree.-70.degree. C. until melted,
adding the component of Phase B without further heating and with
constant and continuous agitation followed by slow addition of the
components of Phase C with constant agitation until a uniform
mixture is obtained. The mixture was then cooled somewhat and
poured into molds at temperatures of from about 50.degree. to
55.degree. C. The antiperspirant stick had enhanced rigidity and
strength and the desired emollient properties without
tackiness.
* * * * *