Note: Descriptions are shown in the official language in which they were submitted.
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TITLE OF THE INVENTION
CATIONIC POLYMER STABILIZED MICROCAPSULE COMPOSITION
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority to United States Patent Application
No.
11/479,679 filed June 30, 2006, the contents of which are incorporated herein
by reference.
BACKGROUND OF THE INVENTION
[0002] Consumer products, such as fabric care products, personal care products
and
home care products are well known in the art and usually comprise one or more
perfumes to
impart the consumer product andlor a substrate treated or applied with the
consumer product
with a fragrance; however, these perfumes dissipate over time from the
consumei- product or
substrate. Another problem with perfumes in consumer products is that they are
released prior to
an optimal delivery time, and the user of the consumer product is deprived of
experiencing the
perfume's fragrance. For example, it is desirable for a perfume to be present
on clothes treated
with a detergent and/or fabric softener long after such treatment, and there
is a tendency for
peifumes to evaporate or diffuse from the clothes over time.
[0003] Thus attempts have been made to minimize the loss of perfumes due to
volatility
and evaporation, and to optimize the release of the perfume's fragrance. One
such approach has
been to encapsulate the perfume within a shell to create a fragrance
microcapsule.
[0004] The calculated log P (Clog P) of many perfumes is known in the art, and
has been
reported, for example, in the Ponoma92 database, available from Daylight
Chemical
Information Systems, Inc. (Daylight CIS) Irvine, CA. Methods of calculating
Clog P are also
known in the art. Perfumes with lower Clog P values may be more volatile and
exhibit higher
aqueous solubility than perfumes having higher Clog P values, and are
therefore preferred to be
used in consumer products. However when lower Clog P materials are
encapsulated, they may
have a greater tendency to leach out of, or diffuse out of the shell into the
consumer product
(preventing optimal delivery of fragrances), and the perfumes may eventually
diffuse out of the
consumer product prior to use by the consumer.
[0005] Methods to prevent the leaching of perfumes from fragrance
microcapsules have
been developed. These inay include coating the interior or exterior of the
shell with one or more
polymers, or incorporation of stabilizing agents in the core. However, there
is a continuing need
to develop systems that deliver fragrances. More efficient delivery systems,
or more stable
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encapsulated perfumes may result in more efficient use of perfumes, thus
decreasing
manufacturing costs.
[0006] When fragrance microcapsules are incorporated in consumer products
containing
solvents andlor surfactants, e.g., shampoos, stability problems may arise. The
encapsulated
perfi.ime may leach out of the shell. The shell may also absorb a solvent,
surfactant, or any other
material in the consumer product, causing the shell's integrity to be
compromised. The shell may
swell because additional materials diffuse into the shell or the core, or the
shell may shrink as
materials of the core diffuse out of the shell. Indeed, components of the
shell may even diffuse
into the consumer product.
[0007] Similar considerations apply to the delivery using microcapsules of
other
materials providing benefits to the consumer, such as flavorants or
antibacterial materials.
[00081 Thus there is a need to develop compositions suitable for use in
compositions that
provide for stability of microcapsules encapsulating fragrance or
antimicrobial materials.
BRIEF SUMMARY OF THE INVENTION
[0009] In one embodiment the invention provides a composition comprising:
a. a microcapsule comprising a shell encapsulating a inaterial having an
average
Clog P of at least about 2.5 and more than 60% by weight of the material has a
Clog P of at least
3.3, and
b. a cross-linked cationic polymer derived from the polymerization of about 5
to 100
mole percent of a cationic vinyl addition monomer, 0 to about 95 mole percent
acrylamide, and
about 5 to about 500 ppm of a difunctional vinyl addition monomer cross-
linking agent.
[0010] In another embodiment, the invention provides a method of improving the
stability of a product that comprises at least one microcapsule comprising
admixing with the
product (before, after, or simultaneously with the addition of the at least
one microcapsule) a
cross-linked cationic polymer derived from the polymerization of about 5 to
100 mole percent of
a cationic vinyl addition monomer, 0 to about 95 percent acrylamide, and about
5 to about 500
ppm of a difiinetional vinyl addition monomer cross-linking agent, wherein the
microcapsule
comprises a shell encapsulating a material having an average ClogP of at least
2.5 and more than
60% by weight of the material has a Clog P of at least 3.3.
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DETAILED DESCRIPTION OF THE INVENTION
[0010] As used throughout, ranges are used as a shorthand for describing each
and every
value that is within the range. Any value within the range can be selected as
the terminus of the
range. Percentages given below are percent of total weight unless otherwise
indicated.
[0011] The present invention is related to the benefit that is provided by use
of a cationic
polymer in a composition containing microcapsules, in particular to
microcapsules having an
average Clog P of at least about 2.5 with more than 60% by weight of the
material having a Clog
P of at least 3.3. The addition of the cationic polymer to the composition
increases the stability
of the microcapsule in the composition compared to compositions lacking such
cationic polymer.
[0012] Perfumes are known in the art and may include odoriferous materials
which are
able to provide a fragrance to consumer products and/or impart a fragrance to
a substrate, e.g..
shampoos and conditioners treat hair. laundry detergents and rinse cycle
fabric softeners treat
fabrics and clothes, glass cleaners treat glass and hard surfaces, colognes,
soaps, deodorants,
antiperspirants and shower gels treat skin and hair. Perfiimes may also
counteract malodors
and/or provide a fragrance. The perfumes may be in liquid state at ambient
temperature, although
solid perfumes may also be useful. Perfumes may include aldehydes, ketones,
esters and other
chemicals and compounds known in the art, including natural, synthetic
perfumes, and mixtures
thereof. Perfumes useful for the present invention may have relatively simple
compositions or
may comprise complex mixtures of natural and synthetic chemical components,
all of which are
intended to provide an odor or fragrance in consumer products, and/or to the
substrate. It is
understood in the present application that a perfume may be substituted with
flavors known in
the art, and that the term perfume, as used herein, also includes flavors.
Generally, perfumes
may be present in consumer products between 0.00001 - 10%.
[0013] Formulations of the invention may comprise unencapsulated fragrance
materials
in addition to any fragrance material present in the microcapsules.
[0014] Fragrance microcapsules are generally known in the art, see ,e.g.,
WO/2004016234, US 2005/0153135, US 2005/0256027, US2004/0072719A1,
US2004/0072720A 1, US20040071.742A 1, US2004/0071746A 1, US 6,194,375, WO
02/074430A1; US 6,620.777, the contents of each patent publication are
incorporated herein by
reference. A fragrance microcapsule generally has a shell which encapsulates a
perfume, and
optionally other materials, such as solvents, surfactants, hydrophobic
polymers, and other
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materials known in the art. The shell may be considered to be made up of a
tight collection of
strands of polymer(s) and may have a diameter less than 1000 m, and the
shells may have a
mean diameter in the range 1 to 500 m, preferably 1 to 300 m, more
preferably 1 to 50 rn and
most preferably 1 to 10 m. The size of the shell may be modified by methods
known in the art.
Preferred sizes for the shell will depend upon their intended use.
[0015] The shell generally prevents leaching of the perfume5 from the consumer
product.
The shell may also bind to substrates, and release the perfume under
predetermined conditions,
i.e., while fabric is being ironed, a fragrance microcapsule on the fabric
bursts due to change in
temperature, or while fabric is being worn, a fragrance microcapsule bursts
due to friction,
shearing, or other physical/mechanical stress caused by the movement of the
wearer.
[0016] A microcapsule's shell may be made by any of the methods known in the
art. The
shell may be a polymer or resin known in the art. Shells comprised of
polyurethane, polyamide,
polyolefin, polysaccaharide, protein, silicone, lipid, modified cellulose,
gums, polyacrylate,
polyphosphate, polystyrene, and polyesters or combinations thereof may be
suitable for use in
the present inventioii. Preferred shells may be an aminoplast which is formed
by the reaction of
one of more amines known in the art with one or more aldehydes known in the
art, such as
formaldehyde. In a preferred embodiment, aminoplasts may be prepared by
polycondensation.
A preferred aminoplast may be a melamine-formaldehyde or urea-formaldehyde
condensate,
such as melamine resiii or urea-formaldehyde resin. Aminoplasts, preferably a
melamine resin,
may be used singularly or in combination with other suitable amides known in
the art.
crosslinking agents known in the art (e.g., toluene diisocyanate, divinyl
benzene, butane diol
diacrylate), and secondary polymers known in the art, such as polymers and co-
polymers of
maleic anhydride. Aminoplasts may also be mixed resins of urea-foi-malehyde,
maleic anhydride
copolymers, and melamine-formalehyde.
[0017] The microcapsules of the present invention have a shell, the shell
having an inner
surface, and an outer surface. The inner surface and/or outer surface of the
shell may be coated,
e.g., with a polymer. The coating on the inner surface and/or outer sLu=face
may improve the
barrier properties of the shell and thus may enhance retention of the
encapsulated materials in
surfactant-containing and/or solvent containing consumer products.
[0018] A cationically charged water-sohible polymer known in the art can be
coated on
shell. The water-soluble polymer can also be an amphoteric polymer with a
ratio of cationic and
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anionic functionalities resulting in a net total charge of zero and positive.
Methods for coating
the cationically charged polymer onto the microcapsule are also known in the
art.
[0019] The application of a coating to the inner sut-face of the shell
capsules may be
caiTied out by a number of methods known in the art. One approach known in the
art involves
the use of a suitable material for the coating which is insoluble in the
material to be encapsulated,
but can be dissolved in a water soluble solvent e.g., ethanol, carbitol, which
is miscible with the
material to be encapsulated. The coating material, typically a polymer, is
dissolved in the
solvent and then the solution is dissolved in the material to be encapsulated.
The material to be
encapsulated is then emulsified into a standard aminoplast capsule forming
aqueous solution. As
the emulsion forms, the solvent is lost to the water and the polymer
precipitates out from solution
at the surface of the emulsion droplets, forming a film at the intei-face of
water/material to be
encapsulated. An encapsulation process known in the art may then be carried
out and the coating
may be deposited on the inner surface of the shell.
[0020] In another method lcnown in the art, a coating material, e.g.,
silicone, used may be
immiscible with materials to be encapsulated and immiscible with water, and is
capable of
forming a thin film at the water interface. A shell encapsulate comprising a
coating of silicone
on the inner surface of the shell can be prepared by dispersing the material
to be encapsulated
within the silicone and then emulsifying this mixture so that an emulsion is
formed where
droplets of encapsulated material are surrounded by a thin film of silicone.
The encapsulation
process is then carried out as known in the art. Alternatively, a thin film
may be formed at the
surface by dispersing the material to be encapsulated in water, adding the
second material e.g.,
silicone and allowing it to coat the encapsulating material droplets
subsequently. An inner
surface coating may also be made from a film-forming polyiner known in the
art, for example:
poly(ethylene-maleic anhydride), povidones, waxes e.g. carbowax,
polyvinylpyrrolidone (PVP)
and its co-polymers such as polyvinylpyrrolidone-ethyl acrylate (PVP-EA),
polyvinylpyrrolidone-vinyl acrylate, polyvinylpyrrolidone methylacrylate (PVP-
MA),
polyvinylpyrrolidone/vinyl acetate, polyvinyl acetal, polyvinyl butyral,
polysiloxane,
poly(propylene maleic anhydride), maleic anhydride derivatives and co-polymers
of the above,
e.g. polyvinyl methyl ether/maleic anhydride. Preferably, the inner wall
coating comprises
polysiloxane, PVP or PVP co-polymers, more preferably PVP or PVP co- polymers,
and even
more preferably PVP co-polymers, particularly PVP-MA or PVP-EA.
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[0021] A coating may be applied to the outer surface of a shell techniques
known in the
art, such as by including spraying, fluid bed coating, or precipitating. For
example a coating, e.g.,
of a polymer, may be precipitated from aqueous solution to condense onto the
outer surface of
the shell or microcapsule, e.g., in the form of a capsules slurry, with
precipitation being caused
by change of temperature, pH, addition of salt, and other variables and
conditions known in the
art. The shell capsule to be coated is thus formed in a separate first step,
prior to the application
of the coating to the outer surface of the shell wall. Depending on the
composition of the outer
surface coating, a coated shell capsule may be prepared for example, by
coacervation or
polycondensation.
[0022] The outer surface coating may comprise high molecular weight, film-
forming
polymers known in the art, which may optionally be cross-linked. "High
molecular weight" is
meant a molecular weight average of greater than 2000 Da, preferably greater
than 4000 Da,
more preferably greater than 5000 Da. The polymer maybe water-soluble or water-
insoluble,
preferably water-soluble. Suitable polymers for use may include, polyvinyl
alcohol (PVOH),
styrene-butadiene latex, gelatin, gum arabic, carboxymethyl cellulose,
carboxymethyl
hydroxyethyl cellulose, hydroxyethyl cellulose, other modified celluloses,
sodium alginate,
chitosan, casein, pectin, modified starch, polyvinyl acetal, polyvinyl
butyral, polyvinyl methyl
ether/maleic anhydride, PVP and its co-polymers (e.g.
polyvinylpyrrolidone/vinyl acetate
(PVP/VA), poly(vinyl pyrrolidone/dimethylaminoethyl methacrylate)
(PVP/DMAEMA),
poly(vinyl pyrrolidone/methacrylamidopropyl trimethyl ammonium chloride),
melamine-
formaldehyde and urea-formaldehyde. Preferably, the outer surface of the shell
is coated with
PVOH, PVP or a PVP co-polymer.
[0023] A preferred coated shell may be an aminoplast capsule having a coating
of
PVOH, PVP or a co-polymer PVP (preferably PVP/DMAEMA) on the outer surface of
the shell
and/or a coating of a film- forming polymer (preferably PVP-EP) on the inner
surface.
[0024] The coating (inner and/or outer) may be cross-linlced in any known
manner, e.g.,
by interfacial cross-linking. A shell capsule usefiil herein may have more
than one coating on the
outer surface of the shell.
[0025] Coated shell capsules typically have a wall thickness in the range of
about 0.01 to
about 30 m, preferably about 0.01 to about 5 m, more preferably about 0.03
to about 1 m,
most preferably about 0.03 to about 0.5 m. The wall thickness inay be
regulated and controlled
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according to the encapsulate size and by varying the relative proportions of
coating and shell
polymer. The weight ratio of coating to shell wall is typically in the range
of about 0.01 to about
10:1, preferably about 0.1:1 to about 10:1, more preferably about 0.1:1 to
about 3:1.
[0026] Typically, the weight ratio of polymer shell wall material to
encapsulated material
is in the range of about 1:10 to about 3:2 and preferably in the range of
about 1:10 to about 1:2.
The coating on the inner su.rface and/or outer surface will increase these
weight ratios.
[0027] When the shell is coated, materials having an average Clog P value
equal to or
greater than 2.5 may be encapsulated, preferably within the range of about 3
to about 5.
Materials used in uncoated microcapsules may include materials wherein at
least about 60%
have a Clog P equal to or greater than about 3.3, preferably greater than
about 4. By "average
Clog P" is meant the average Clog P for all of the encapsulated materials.
Thus the average Clog
P of the encapsulated materials may be raised, for example, by adding a
solvent having a high
C1ogP, e.g., about 6 or greater, wherein the solvent is miscible with the
other encapsulated
materials.
[0028] One or more perfumes may be used in the present invention as a mixture
of
perfumes. Thus, for microcapsules having a shell without a coating, a mixture
of perfumes
greater than about 60 weight percent of the fragrance materials have a Clog P
of greater than
about 3.3, preferably more than about 80 weight percent of the fragrances have
a Clog P value of
greater than about 4.0, and more preferably, more than about 90 weight percent
of the fragrances
have a Clog P value of greater than about 4.5 may be used.
[0029] The microcapsule contains a core within the shell, and the core
comprises a
perfume or other benefit agent, such as a flavorant or antibacterial material,
and may optionally
contain other materials known in the art, for example, hydrophobic solvents
such as triglyceride
oil, mono and diglycerides, mineral oil, silicone oil, diethyl phthalate,
polyalphaolefins, fatty
alcohols, castor oil and isopropyl myristate. The solvent materials may be
miscible with the
benefit agents. For microcapsules having a shell without a coating on the
inner or outer surface,
suitable solvents include those having reasonable affinity for the pei-fume,
and the solvent may
have a Clog P greater than 3.3, preferably greater than 6 and most preferably
greater that 10. A
preferred solvent may be isopropyl myristate. A preferred solvent may also be
silicone, such
polydimethylsiloxane and polydimethylcyclosiloxane. In another embodiment of
the present
invention, a preferred solvent may be diethyl phthalate. The solvent may be
greater than about 30
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weight percent. preferably greater than about 50 weight percent and more
preferably greater than
about 70 weight percent of the core.
[0030] It is known in the art that the addition of hydrophobic polymers in a
microcapsule
may also improve stability of the microcapsule by slowing diffusion of the
perfume from the
shell. The amount of the hydrophobic polymer may be less than 80% of the
microcapsule by
weight, preferably less than 50%, and most preferably less than 20%. A
hydrophobic polymer
may be ethyl cellulose, hydroxypropyl cellulose, cellulose acetate butyrate,
ethylene vinyl
acetate, polystyrene, and PVP and ester terminated polyamides or amide
terminated polyamides.
[0031] As previously described, when microcapsules are incorporated in certain
solvents
and/or surfactant- containing consumer products. e.g., shampoos, stability
problems may arise.
Thus in the present invention, a cationic polymer is added to the consumer
product to increase
the stability of the microcapsule.
[0032] The cationic polymer in the present invention is a cross-linked polymer
which is
cross-linked using a cross-linking agent of a difunctional vinyl addition
monomer at a level of
about 5-500 ppm, preferably about 70 to about 300 ppm, preferably about 75 to
about 200ppm,
and most preferably of from about 80 to about 150 ppm. The cationic polymer
may be a cationic
vinyl polymer. A cationic vinyl polymer may be derived from the polymerization
of from about
to 100 mole percent of a cationic vinyl addition monomer and 0 to about 95
mole percent of
acrylamide. The difunctional vinyl addition monomer may be a polyethylene
glycol diacrylic
ester having a weight average molecular weight of from 300 to 3,000.
[0033] The cationic polymer may be derived from the polymerization of about 5
to 100
mole percent of a cationic vinyl addition monomer, 0 to about 95 mole percent
of acrylamide,
and about 70 to about 300 ppm of a difunctional vinyl addition monomer
crosslinking agent.
The difunctional vinyl addition monomer may be a polyethylene glycol diacrylic
ester having a
weight average molecular weight of about 300 to about 3,000.
[0034] The cationic polymer may also be a cross-linked cationic vinyl addition
polymer
derived from the polymerization of about 15 to about 70 mole percent of a
quaternary
ammonium salt of dimethyl/aminoethylmethacrylate and about 30 to about 85 mole
percent of
acrylamide, and about 0.005 to about 0.025 weight percent of the polyethylene
glycol diacrylic
ester. The polyethylene glycol diacrylic ester may be polyethylene glycol
dimethacrylate.
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[0035] The cationic polymer may be prepared as water in oil emulsions, wherein
the
cross-linked polymers are dispersed in the oil, preferably a mineral oil. A
cationic polymer may
be a cross-linked copolymer of a quatemary ammonium acrylate or methacrylate
in combination
with an acrylamide comonomer. Additional description of cationic polymers
useful in the
present invention may be found in U.S. Patent Nos. 4,806,345 and 6,864,223,
which are
incorporated herein by reference.
[0036] A composition may comprise about 0.001 % to about 40% total weight of
the
cationic polymer, preferably about 0.01% to about 10%, more preferably, about
0.01% to about
5%. The amount of cationic polymer present will depend upon the composition
and the
microcapsule used therein. The cationic polymer may be admixed to the consumer
product
before, during or after the addition of a microcapsule to the consumer
product.
[0037] As described herein, the cationic polymer is well suited for use in a
variety of
well-known consumer products comprising a microcapsule, such as oral care
products,
toothpastes, mouthwashes, personal care products, lotions, creams, shampoos,
conditioners, hair
gel, antiperspirants, deodorants, shaving creams, hair spray, colognes, body
wash, home care
products, laundry detergent, fabric softeners, liquid dish detergents, tumble
dryer sheets,
automatic dish washing detergents, and hard surface cleaners. These consumer
products may
employ surfactant, solvents and emulsifying systems that are well known in the
art. In the
consumer product base, a fragrance is used to provide the constimer with a
pleasurable fragrance
during and after using the product or to mask unpleasant odors from some of
the fimctional
ingredients used in the product. As stated above, a problem with the use of
encapsulated
fragrance in product bases is the loss of the fragrance before the optimal
time for fragrance
delivery.
[0038] In the present invention, the microcapsule may be in an aqueous
solution of a
consumer product. Alternatively, the microcapsule may be in the continuous
phase of an oil-in-
water emulsion of a consumer product. Alternatively, the microcapsule may be
in the
discontinuous phase of an oil-in-water emulsion of a consumer product.
Alternatively, the
microcapsule may be in the discontinuous phase of a water-in-oil emulsion of a
consumer
product. Alternatively, the niicrocapsule may be in the continuous phase of a
water-in-oil
emulsion of a consumer product.
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[0039] Consumer products may be made using an aqueous base containing a
surfactant,
although some products use glycols, polyhydric alcohols, alcohols, or silicone
oils as the
dominant solvent or carrier. Suitable surfactant agents for use in the present
invention include
those surfactants that are commonly used in consumer products such as laundry
detergents,
fabric softeners and the like. The products commonly include cationic
surfactants which also are
used as fabric softeners; as well as nonioinic and anionic surfactants which
are known in the art.
Surfactants are normally present at levels of about 1 to 30 weight %. In soine
instances the
surfactant loading may be more than 85, typically more than 95 and greater
than about 99 weight
% of the formulated product.
[0040] The present invention is further illustrated for use in a consumer
product, such as
a fabric softener composition. Fabric softener compositions are known in the
art, and contain a
fabric softening component, and other optional materials such as perfumes,
chelators,
preservatives, dyes, soil release polymers, and thickeners. Other optional
ingredients may also
include solvents, alcohols, amphoteric and non-ionic surfactants, fatty
alcohols, fatty acids,
organic or inorganic salts, pH buffers, antifoams, germicides, ftuigicides,
antioxidants, corrosion
inhibitors, enzymes, optical brighteners, antifoams, and other materials known
in the art.
[0041] A fabric softener composition may be substantially free of anionic
surfactants
known in the art, such as, lithium dodecyl sulfate, or sodium dodecyl sulfate.
By substantially
free is meant that the fabric softener composition contains less than 5%
weight of anionic
surfactant, preferably less than 1% by weight, more preferably less than .5%
by weight and still
more preferably less than 0.1% by weight of an anionic surfactant.
[0042] A fabric softener composition may be substantially free of water
soluble builder
salts known in the art, such as alkali metal phosphates, such as sodium
phosphate and potassium
phosphate. By substantially free is meant that the fabric softener composition
contains less than
5% weight of a builder salt, preferably less than 1% by weight, more
preferably less than 0.5%
by weight and still inore preferably less than 0.1% by weight an water soluble
builder salt.
[0043] Fabric softening components in fabric softener coinpositions are well
known in
the art, and may include cationic surfactants, quateinary ammonium salts
(acyclic quaternary
ammonium salts, ester quaternary ammonium salts, cyclic quaternary ammonium
salts, diamido
quaternary ammonium salts, biodegradable quaternary ammonium salt, polymeric
ammonium
salts), polyquats, tertiary fatty amines, carboxylic acids, esters of
polyhydric alcohols, fatty
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alcohols, ethoxylated fatty alcohols, alkyphenols, ethoxylated alkyphenols,
ethoxylated fatty
amines, difatty, ethoxylated monolycerides, ethoxylated diglycerides, mineral
oils, clays, and
polyols.
[0044] A fabric softener composition may comprise about 0.0 1% to about 35% by
weight
of one or more fabric softening components. Preferably, the present invention
may comprise
about 0.5% to about 25% weight of a fabric softening component. Optionally,
the present
invention may comprise about 1.5% to about 12% of a fabric softening
component. Optionally,
the present invention may comprise about 15% to about 24% of a fabric
softening component.
[0045] The amount of the components in a fabric softener composition will
depend on
the pi.upose of the formulation, i.e., whether the formulation concentrated or
dilute. Thus, the
fabric softening component may, for example, be about 0.1% to about 50% of the
total weight of
the composition, e.g., about 10% to about 25% for a concentrated composition
and about 1 to
about 10% for a dilute composition. The fabric softener composition may also
have one or more
chelators, dyes, fatty alcohols, preservatives and/or perfumes, and/or other
ingredients as known
in the art.
[0046] A fabric softening component may be an esterquat (or mixttu=e of
esterquats)
having the formula of structure 1
R +
2
\ R3
O
Rj \ I I ~_
(CH2)q O C R4
STRUCTURE 1
wherein
Ri represents -(CH2),R6 where R6 represents benzyl, phenyl, (CI-C4)-alkyl
substituted
phenyl, OH or H;
R, and R3 represent -(CH,))S-R5 where R5 represents an acyloxy group
containing from 8
to 22 carbon atoms, benzyl, phenyl, (C1-C4)-alkyl substituted phenyl, OH or H;
R4 represents an aliphatic hydrocarbon group having from 8 to 22 carbon atoms;
q, s, and t, each independently, represent an integer from 1 to 3; and
X- is a softener compatible anion.
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[0047] A particular softener for use in the present invention is produced by
reacting two
moles of fatty acid methyl ester with one mole of triethanolamine followed by
quaternization
with dimethyl sulfate (further details on this preparation method are
disclosed in US 3,915.867,
which is incorporated herein by reference). The reaction products are
distributed as follows: (a)
50% diesterquat material; (b) 20% monoesterquat; and (c) 30% triesterquat.
[0048] Depending on the esterification process conditions, the distribution of
the three
species (mono, di and tri) may vary. The esterquat compounds described herein
are prepared by
quaternizing the product of the condensation reaction between a fatty acid
fraction containing at
least one saturated or unsaturated linear or branched fatty acid, or
derivative, and at least one
functionalized tertiary amine, wherein the molar ratio of the fatty acid
fraction to tertiary amine
is about 1.7 : 1. The method of manufacture for such a esterquat surfactant is
described in US
Patent 5,637,743 (Stepan), the disclosure of which is incorporated herein by
reference.
[0049] The aforementioned molar ratio will determine the equilibrium between
the
mono. di and tri-esterquat compounds in the products. For example, using a
molar ratio of about
1.7 results in a normalized distribution of about 34% mono-esterquat, about
56% of di-esterquat
and about 10% of tri-esterqLiat which is a fatty ester quat compound in
accordance with the
invention. On the other hand, for example, using a molar ratio of about 1.96
results in a
normalized distribution of about 21 % mono-esterquat, 61% of di-esterquat and
18% of tri-
esterquat.
[0050] A preferred fabric softening component may thus include a quaternized
fatty acid
triethanolamine ester salt, e.g., a triethanolamine-esterquat tallow. A
preferred fabric softening
component of the present invention may include a di-alkyl ester of triethanol
ammonium methyl
sulfate, or a dihydrogenated tallowoylethyl hydroxyethylmonium methosulfate.
Fabric softening
components may be purchased from Kao Corporation under the product name
Tetranyl L1/90 or
Tetranyl AT1-75.
[0051] Fabric softener compositions may also comprise soil release polymers
(SRP's).
SRP's are well known in the art, and may iiiclude polymers which are absorbed
onto fabric fibers
where they counteract resoiling of the fibers. The polymers may include
polyesters and co-
polymers of terephthalic acid, polyesters of and co-polymers of ethylene
glycol, copolymers of
ethylene glycol and benzene, and polyethylene terephthalate. The polymers may
include
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nonionic polyesters. The polymers may be modified whereby a portion of the
ethylene glycol is
removed and replaced with a high molecular weight hydroxy-terminated
polyethylene glycol.
[0052] Chelating agents are well known in the art, and may be present at a
level of at
least about 0.001%, by weight, of the fabric softening composition, preferably
about 0.001% to
about 1%, more preferably about 0.01% to about 0.5%, more preferably about
0.06% - 0.1% by
weight. The chelating agents may be selected from among amino carboxylic acid
compounds
and organo aminophosphonic acid compounds, and mixtures of the same. Suitable
amino
carboxylic acid compounds may include: ethylenediamine tetraacetic acid, N-
hydroxyethylenediamine triacetic acid, nitrilotriacetic acid, and
diethylenetriamine pentaacetic
acid. Suitable organo aminophosphonic acid compounds may include
methylenephosphonic
acid, 1-hydroxyethane 1,1-diphosphonic acid, and aminotrimethylene phosphonic
acid. A
preferred chelating agent may be an aminotrimethylene phosphonic acid, which
may be obtained
from Solutia, Inc. (St. Louis, Missouri, USA) as Dequest 2000.
[0053] Preservatives are well known in the art, and may include lactic acid,
formaldehyde, or other preservatives known in the art. A fabric softener
composition may
comprise 0% to about 10% weight of a preservative, preferably, about 0.01% to
about 2%, more
preferably about 0.05% to about 0.5%. A preferred preservative in the present
invention may be
lactic acid.
[0054] Fatty alcohols and aliphatic alcohols are known in the art. Fatty
alcohols may
have carbon chain which are fully saturated or unsaturated. Preferred fatty
alcohols include Clo-
C2S alcohols, preferably C16_ 18. C13-C15 alcohols, and mixtures thereof. A
fabric softener
composition may comprise 0% to about 10% weight of a fatty alcohol, preferably
about 0.1% to
about 5%, and more preferably about 0.1% to about 0.5% of a fatty alcohol.
[0055] Dyes are well known in the art and may comprise 0% to about 5% of a
product.
[0056] In another embodiment, the invention provides a method of delivering a
fragrance
or antimcrobial material in a product comprising admixing any of compositions
into a consumer
product. The consumer procluct may be a oral care product, toothpaste,
mouthwash, personal
care product, lotion, cream, shampoo, conditioner, hair gel, antiperspirant,
deodorant,
antiperspirant and deodorant, shaving cream, hair spray, cologne, body wash,
home care product,
laundry detergent. fabric softener, liquid dish detergent, tumble dryer sheet,
automatic dish
detergent, or hard surface cleaner.
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EXAMPLES
Example 1
[0057] The following compositions are prepared by mixing in deionized water to
create
an emulsion (percentages are percentage of total weight):
FC#1 FC#2
TEA-esterquat tallow 8.667% 8.667%
Cationic polymer 0.268% -
Ainino trimethylene 0.1% 0.1%
phosphonic acid
Lactic acid 0.063 % 0.063 %
Fragrance microcapst-le 3.6% 3.6%
Water Balance Balance
[0058] Water and TEA-esterquat tallow are each separately heated to 65 C. Add
amino
trimethylene phosphonic acid to the water and mix. Add TEA-esterquat the water
at a rate of
about between 25 to 40 grams per minute. Mix for 10 minutes, and cool while
mixing in an
ice/water bath until a temperature of 35 C is reached. Add lactic acid and
mix. Add cationic
polymer, and mix for 10 minutes. Fragrance microcapsules are added, and the
solution is mixed
for an additional 30 minutes.
Example 2
[0059] Cotton teiYy towels are washed in laundry washing machines with equal
amounts
of compositions FC#1 and FC#2. Following washing, the towels are line dried
for one day at
room temperature. A panel of 20 judges is asked to evaluate the towels washed
with FC#1 and
FC#2 according to odor. 63% of the judges preferred towels washed with FC#1.
The towels are
then nibbed and judges are asked to reevaulate the towels. 70% of the judges
preferred FC#1.
The results show that the towels washecl in FC#1 with the cationic polymer
with the fragrance
microcapsules gave an increased fragrance.
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Example 3
[0060] The following compositions are prepared by mixing in deionized water to
create
an emulsion (percentages are percentage of total weight):
FC#3 FC#4
Tetranyl L1/90 8.667% 8.667%
Cationic polymer 0.268% 0.268%
Dequest2000 0.1% 0.1%
Lactic acid 0.063 % 0.063 %
Fragrance 0.99% -
Fragrance microcapsule - 5.723% (0.99%
(17.3% fragrance) fragrance)
Water Balance Balance
[0061] Water and Tetranyl L1/90 are each separately heated to 65 C. Add
Dequest2000 to the water and mix. Add Tetranyl L1/90 to the water at a rate of
about between
25 to 40 grams per minute. Mix for 10 minutes, and cool while mixing in an
ice/water bath
until a temperature of 35 C is reached. Add lactic acid and mix. Add cationic
polymer, and
mix for 10 minutes. Fragrance microcapsules and fragrance are added to
respective
foimulations, and the solutions are mixed for an additional 30 minutes.
Example 4
[0062] Cotton terry towels are washed in laundry washing machines with equal
amounts of compositions FC#3 and FC#4. Following washing, the towels are
stored for 1
week at temperature for 1 week, 3 months at 35 C, and one month at 43 C.
Following storage,
a panel of 20 judges is asked to rate the intensity of the perfume on the
towel, and the intensity
of the perfume on the towel after rubbing the towel several times. The results
are shown in the
chart below. The towels washed in FC#4 with the encapsulated fragrance with
the cationic
polymer outperformed the towels washed 'ul FC#3 without the encapsulated
fragrance.
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WO 2008/005693 PCT/US2007/071782
8 1 Week Aged at 3 Months A ed- 1 Month-Aged
- ~ - _ - --- - -~
7 Room Temp. at 35 C at 43 C
~
~ 4 Unrubbed
3 ^ Rubbed
~ ~%; = ~i~ ~!'~ /
a~ 2
~ O
w FC#3 FC#4 FC#3 FC#4 FC#3 FC#4
[0063] The matters set here are offered by way of illustration only and not as
limitations. While particular embodiments have been shown and described, it
will be apparent
to those skilled in the art that changes and modifications may be made without
departing from
the broader aspects of invention. The actual scope of the protection sought is
intended to be
defined in the following claims when viewed in their proper perspective based
on the prior art.
16
