U.S. patent application number 15/808845 was filed with the patent office on 2018-03-08 for reloadable microcapsules.
The applicant listed for this patent is INTERNATIONAL FLAVORS & FRAGRANCES INC.. Invention is credited to John BRAHMS, Frederique Marie-Helene Brigitte CARPUAT, Manon Blandine Marie GILLES, Yabin LEI, Lewis Michael POPPLEWELL, Julie WIELAND, Li XU.
Application Number | 20180064615 15/808845 |
Document ID | / |
Family ID | 60203259 |
Filed Date | 2018-03-08 |
United States Patent
Application |
20180064615 |
Kind Code |
A1 |
BRAHMS; John ; et
al. |
March 8, 2018 |
RELOADABLE MICROCAPSULES
Abstract
A reloadable microcapsule contains a microcapsule core and a
microcapsule wall encapsulating the microcapsule core. The
microcapsule core contains a hydrophobic core solvent and a
hydrophilic core solvent, and the microcapsule wall, formed of an
encapsulating polymer, is permeable to the hydrophilic core
solvent. Also disclosed are methods of preparing the reloadable
microcapsule and consumer products having the microcapsules.
Inventors: |
BRAHMS; John; (Morris
Plains, NJ) ; LEI; Yabin; (Holmdel, NJ) ;
WIELAND; Julie; (Edison, NJ) ; XU; Li;
(Edison, NJ) ; POPPLEWELL; Lewis Michael;
(Morganville, NJ) ; CARPUAT; Frederique Marie-Helene
Brigitte; (La Garenne -Colombes, FR) ; GILLES; Manon
Blandine Marie; (CLICHY, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
INTERNATIONAL FLAVORS & FRAGRANCES INC. |
New York |
NY |
US |
|
|
Family ID: |
60203259 |
Appl. No.: |
15/808845 |
Filed: |
November 9, 2017 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/US2017/030729 |
May 3, 2017 |
|
|
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15808845 |
|
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62331230 |
May 3, 2016 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61K 9/5031 20130101;
C11D 17/0039 20130101; A61K 9/4808 20130101; C11D 11/0017 20130101;
A61Q 15/00 20130101; D06M 13/005 20130101; A61K 9/5005 20130101;
A61K 8/11 20130101; A61K 8/25 20130101; A61K 8/87 20130101; A61K
8/84 20130101; A61Q 19/00 20130101; A61K 9/4816 20130101; D06M
2200/50 20130101; A01N 25/28 20130101; A61K 2800/412 20130101; A61K
9/06 20130101; B01J 13/203 20130101; C11D 3/0015 20130101; C11D
7/5022 20130101; D06M 23/12 20130101; C11D 17/0013 20130101; A61Q
13/00 20130101; C11D 3/43 20130101; A61K 8/65 20130101; A61K 9/0014
20130101; A61K 8/046 20130101; A61K 8/375 20130101; C11D 3/505
20130101; A01N 37/18 20130101; A61K 8/43 20130101; D06M 23/06
20130101; A61K 8/37 20130101 |
International
Class: |
A61K 8/11 20060101
A61K008/11; A01N 25/28 20060101 A01N025/28; A01N 37/18 20060101
A01N037/18; A61K 8/37 20060101 A61K008/37; A61K 8/84 20060101
A61K008/84; A61K 8/43 20060101 A61K008/43; A61Q 15/00 20060101
A61Q015/00; A61Q 19/00 20060101 A61Q019/00; A61K 8/65 20060101
A61K008/65; A61K 8/25 20060101 A61K008/25; C11D 3/50 20060101
C11D003/50; C11D 17/00 20060101 C11D017/00; C11D 3/00 20060101
C11D003/00; C11D 11/00 20060101 C11D011/00 |
Claims
1. A microcapsule comprising a microcapsule core and a microcapsule
wall encapsulating the microcapsule core, wherein the microcapsule
wall, formed of an encapsulating polymer, is permeable to the
hydrophilic core solvent, and the microcapsule core contains by
weight of the core 1 to 99% of the hydrophilic solvent and 1 to 99%
of the hydrophobic solvent, preferably 10 to 90% of the hydrophilic
solvent and 10 to 90% of the hydrophobic solvent, more preferably
25 to 75% of the hydrophilic solvent and 25 to 75% of the
hydrophobic solvent, and most preferably 40 to 60% of the
hydrophilic solvent and 40 and 60% of the hydrophobic solvent.
2. The microcapsule of claim 1, wherein the microcapsule core is
free of an active material; the hydrophilic core solvent has a
water solubility of 1 to 100 g/L, a weighted Hansen solubility
parameter of 18 or greater, a Hansen polarizability of 4 or
greater, and a Hansen h-bonding value of 5 or greater; and the
hydrophobic core solvent has a weighted Hansen solubility parameter
of 18 or less, a Hansen polarizability of 4 or less, and a Hansen
h-bonding value of 5 or less.
3. The microcapsule of claim 2, wherein the hydrophilic core
solvent has a vapor concentration at 25.degree. C. of 4 .mu.g/L or
greater; and the hydrophobic core solvent has a vapor concentration
at 25.degree. C. of 0.1 .mu.g/L or less.
4. The microcapsule of claim 1, wherein the microcapsule has a size
of 0.1 to 1000 .mu.m in diameter, the weight ratio between the
hydrophobic core solvent and the hydrophilic core solvent is 1:9 to
9:1, and the weight ratio between the microcapsule core and the
microcapsule wall is 50:1 to 1:1.
5. The microcapsule of claim 2, wherein the hydrophilic core
solvent is triethyl citrate, triacetin, benzyl acetate, benzyl
benzoate, ethyl acetate, propylene glycol, dipropylene glycol,
dipropylene glycol methyl ether, a glycol ether, or a combination
thereof; and the hydrophobic core solvent is a C.sub.3-C.sub.40
ester, isopropyl myristate, C.sub.5-C.sub.50 triglyceride,
D-limonene, silicone oil, mineral oil, isopropyl palmitate,
isoparaffinic hydrocarbon, methyl hydrogenated rosinate, dioctyl
adipate, or a combination thereof.
6. The microcapsule of claim 1, wherein the hydrophobic solvent is
a fragrance ingredient having a ClogP of 2.5 or greater and a vapor
concentration at 25.degree. C. of 0.1 .mu.g/L or less, and the
hydrophilic core solvent has a vapor concentration at 25.degree. C.
of 4 .mu.g/L or greater.
7. The microcapsule of claim 1, wherein the encapsulating polymer
is a polyacrylate, polyurea, polyurethane, polyacrylamide,
polyester, polyether, polyamide, poly(acrylate-co-acrylamide),
starch, silica, gelatin and gum Arabic, alginate, chitosan,
polylactide, poly(melamine-formaldehyde), poly(urea-formaldehyde),
or combination thereof.
8. The microcapsule of claim 7, wherein the encapsulating polymer
is a polyurea, the microcapsule core contains a C.sub.1-C.sub.30
alcohol or thiol, the polyurea is a reaction product of a
polyisocyanate and a polyamine, the polyisocyanate is a trimer of
hexamethylene diisocyanate, a trimer of isophorone diisocyanate, a
biuret of hexamethylene diisocyanate, a polyisocyanurate of toluene
diisocyanate, a trimethylol propane-adduct of toluene diisocyanate,
a trimethylol propane-adduct of xylylene diisocyanate, or a
combination thereof, and polyisocyanate is hexamethylene diamine,
branched polyethylenimine, guanidine, or a combination thereof.
9. A microcapsule composition comprising the microcapsule of claim
1 and a continuous phase that has an external hydrophilic solvent
and an active material, wherein the microcapsule wall is permeable
to the active material, the ratio between the microcapsule core and
the active material is 1:99 to 99:1, and the active material is
selected from the group consisting of a fragrance, pro-fragrance,
flavor, malodor counteractive agent, vitamin or derivative thereof,
anti-inflammatory agent, fungicide, anesthetic, analgesic,
antimicrobial active, anti-viral agent, anti-infectious agent,
anti-acne agent, skin lightening agent, insect repellent, animal
repellent, vermin repellent, emollient, skin moisturizing agent,
wrinkle control agent, UV protection agent, fabric softener active,
hard surface cleaning active, skin or hair conditioning agent,
flame retardant, antistatic agent, taste modulator, cell,
probiotic, antioxidant, self-tanning agent, dihydroxyacetone,
cooler, sensate, malodor reactive material, cosmetic active, and
combinations thereof.
10. The microcapsule composition of claim 9, wherein the external
hydrophilic solvent is water, ethanol, propanol, dipropylene
glycol, propylene glycol, glycerin, diethyl phthalate, or a
combination thereof.
11. The microcapsule composition of claim 9, wherein the active
material is a fragrance having a weighted Hansen solubility
parameter of 15 to 20, a Hansen polarizability of 5 or less, and a
Hansen h-bonding value of 10 or less.
12. The microcapsule composition of claim 9, wherein the active
material is a fragrance having an average vapor concentration at
25.degree. C. of 500 .mu.g/L or more and present at a level of
0.005 to 30% by weight of the microcapsule composition.
13. The microcapsule composition of claim 9, wherein the fragrance
contains two or more fragrance ingredients, 50 weight % or more of
the fragrance ingredients have a water solubility of 100 ppm or
less, 50 weight % or less of the fragrance ingredients have a vapor
concentration of 100 .mu.g/L or less, and 30 weight % or less of
the fragrance ingredients have a CLogP of 3 or less.
14. The microcapsule composition of claim 9, wherein the Euclidian
difference in solubility parameter between the fragrance and the
hydrophilic core solvent is less than the Euclidian difference
between the fragrance and the hydrophobic core solvent.
15. The microcapsule composition of claim 9, wherein the Euclidian
difference in solubility parameter between the fragrance and the
hydrophobic core solvent is less than 5.
16. The microcapsule composition of claim 9, further comprising a
deposition aid selected from the group consisting of
polyquaternium-4, polyquaternium-5, polyquaternium-6,
polyquaternium-7, polyquaternium-10, polyquaternium-16,
polyquaternium-22, polyquaternium-24, polyquaternium-28,
polyquaternium-39, polyquaternium-44, polyquaternium-46,
polyquaternium-47, polyquaternium-53, polyquaternium-55,
polyquaternium-67, polyquaternium-68, polyquaternium-69,
polyquaternium-73, polyquaternium-74, polyquaternium-77,
polyquaternium-78, polyquaternium-79, polyquaternium-80,
polyquaternium-81, polyquaternium-82, polyquaternium-86,
polyquaternium-88, polyquaternium-101, polyvinylamine,
polyethyleneimine, polyvinylamine and vinylformamide copolymer,
polymer comprising units derived from polyethylene glycol and
terephthalate, hydroxypropylcellulose, a polysaccharide, and
combinations thereof.
17. A method of preparing a microcapsule composition of claim 9,
the method comprising the steps of: (a) providing a microcapsule
that has a microcapsule core and a microcapsule wall encapsulating
the microcapsule core, in which the microcapsule core contains a
hydrophobic core solvent and a hydrophilic core solvent, and the
microcapsule wall is formed of an encapsulating polymer and
permeable to the hydrophilic core solvent; (b) providing a
continuous phase that has an external hydrophilic solvent and an
active material; (c) mixing the microcapsule and the continuous
phase to obtain a microcapsule dispersion; and (d) aging the
microcapsule dispersion to obtain the microcapsule composition.
18. A consumer product comprising the microcapsule composition of
claim 9, wherein the consumer product is selected from the group
consisting of: a baby care product, a diaper rash cream or balm, a
baby powder, a diaper, a bib, a baby wipe, a cosmetic preparation,
a powder foundation, a liquid foundation, an eye shadow, a lipstick
or lip balm, a home care product, an all-purpose cleaner, a
bathroom cleaner, a floor cleaner, a window cleaner, a plastics
polish, a bleach, a toilet cleaner, a toilet rimblock, a bath
tissue, a paper towel, a disposable wipe, liquid air freshener, air
freshener spray, a spray dispenser product, an incense stick, a rug
deodorizer, a candle, a room deodorizer, a liquid dish detergent,
an automatic dish detergent, a powder dish detergent, a leather
detergent, a tablet dish detergent, a paste dish detergent, a unit
dose tablet or capsule, a flavor, a beverage flavor, a diary
flavor, a fruit flavor, a miscellaneous flavor, a sweet goods
flavor, a tobacco flavor, a toothpaste flavor, a chewing gum, a
breath freshener, an orally dissolvable strips, a chewable candy, a
hard candy, an oral care product, a tooth paste, a toothbrush, a
dental floss, an oral rinse, an tooth whitener, a denture adhesive,
a health care device, a tampon, a feminine napkin, an
anti-inflammatory balm, an anti-inflammatory ointment, an
anti-inflammatory spray, a disinfectant, a personal care product, a
soap, a bar soap, a liquid soap, a bath fragrance, a body wash, a
non-aerosol body spray, a body milk, a cleanser, a body cream, a
hand sanitizer, a hand wash, a functional product base, a sunscreen
lotion, a sunscreen spray, a deodorant, an anti-perspirant, an
roll-on product, an aerosol product, a natural spray product, a
wax-based deodorant, a glycol type deodorant, a soap type
deodorant, a facial lotion, a body lotion, a hand lotion, a
miscellaneous lotion, a body powder, a shave cream, a shave gel, a
shave butter, a bath soak, a shower gel, an exfoliating scrub, a
foot cream, a facial tissue, a cleansing wipe, a talc product, a
hair care product, a hair care with ammonia, a shampoo, a hair
conditioner, a hair rinse, a hair refresher, a hair fixative or
styling aid, a hair bleach, a hair dye or colorant, a fabric care
product, a fabric softener, a liquid fabric softener, a fabric
softener sheet, a drier sheet, a fabric refresher, an ironing
water, a detergent, a laundry detergent, a liquid laundry
detergent, a powder laundry detergent, a tablet laundry detergent,
a laundry detergent bar, a laundry detergent cream, a hand wash
laundry detergent, a scent booster, a fragrance, a cologne,
compounds, an encapsulated fragrance, a fine fragrance, a men's
fine fragrance, a women's fine fragrance, a perfume, a solid
perfume, an Eau De Toilette product, a natural spray product, a
perfume spray product, an insect repellent product, and a wildlife
scent.
19. The consumer product of claim 18, wherein the consumer product
is an aerosol product or natural spray product, each of which
contains 0.01 to 50% of the microcapsule composition of claim
9.
20. The consumer product of claim 18, wherein the consumer product
is a perfume spray product containing 0.01 to 40% of the
microcapsule composition, 0.01 to 40% of a fragrance as the active
material, at least 60% of ethyl alcohol, 0 to 30% of a suspending
polymer, and 0 to 30% of an emollient.
21. The consumer product of claim 20, wherein the suspending agent
is polyacrylate crosspolymer-6, acrylates/C10-C30 alkyl acrylate
crosspolymer, or a combination thereof, and the emollient is
trilsononanoin, ethylhexyl isononanoate, cyclopentasiloxane, or a
combination thereof.
22. The consumer product of claim 18, wherein the consumer product
is an insect repellent containing 2 to 95% of
N,N-Diethyl-meta-toluamide and 1 to 30% of the microcapsule
composition.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of priority from
International Patent Application No. PCT/US2017/030729, filed on
May 3, 2017, which claims priority to U.S. Application Ser. No.
62/331,230, filed on May 3, 2016. The contents of both applications
are incorporated by reference in their entirety.
BACKGROUND
[0002] Microcapsules are useful in a variety of applications where
there is a need to deliver, apply, or release a fragrance or other
active material in a time-delayed and controlled manner.
[0003] Conventional microcapsules each have a polymeric shell
encapsulating an active material in a microcapsule core. The
polymeric shell is typically formed via an interfacial
polymerization reaction, namely, a polymerization that occurs at an
interface between an aqueous phase and an oil phase. These
microcapsules have been developed to provide good performance in
various consumer products such as laundry detergents. See, e.g.,
U.S. Pat. No. 7,491,687, U.S. Pat. No. 6,045,835, US 2014/0287008,
and WO 2015/023961. Polyurea microcapsules have been developed for
delivering fragrances. Their preparation involves the
polymerization reaction between wall-forming materials, e.g., a
polyisocyanate and a polyamine. During the polymerization reaction,
the polyisocyanate can react with many fragrance ingredients such
as primary alcohols contained in a fragrance accord. The other
wall-forming material polyamine is also reactive towards aldehyde
fragrance ingredients. Primary alcohols and aldehydes are common
ingredients in many fragrance accords. Such fragrances are not
suitable to be encapsulated by conventional microcapsules. In
addition, fragrance ingredients having a high water solubility are
also unsuitable for conventional encapsulation as these ingredients
tend to stay in the aqueous phase instead of being encapsulated in
the microcapsule oil core. Challenges remain in encapsulating
fragrances and other active materials without losing reactive or
water-soluble ingredients.
[0004] There is a need to develop a microcapsule suitable for
encapsulating fragrances having ingredients that either have a high
water solubility or are reactive towards wall-forming
materials.
SUMMARY
[0005] This invention is based on the discovery that reloadable
microcapsules can be prepared in absence of an active material
(e.g., fragrance), thus avoiding the reaction between the active
material and a wall-forming material. This reloadable microcapsule
unexpectedly improves substantivity of a free fragrance on fabric
or skin. It provides a facile method for delivering active
materials in consumer products.
[0006] Accordingly, one aspect of this invention relates to
microcapsules each having a microcapsule core and a microcapsule
wall. The microcapsule core is encapsulated in the microcapsule
wall and contains a hydrophilic core solvent and/or a hydrophobic
core solvent. The microcapsule wall, formed of an encapsulating
polymer, is permeable to the hydrophilic core solvent and the
active material.
[0007] The microcapsule core typically contains by weight of the
core 1 to 99% of the hydrophilic solvent and 1 to 99% of the
hydrophobic solvent, preferably 10 to 90% of the hydrophilic
solvent and 10 to 90% of the hydrophobic solvent, more preferably
25 to 75% of the hydrophilic solvent and 25 to 75% of the
hydrophobic solvent, and most preferably 40 to 60% of the
hydrophilic solvent and 40 and 60% of the hydrophobic solvent.
[0008] In some embodiments, the microcapsule core, free of an
active material (e.g., a fragrance), consists of a hydrophobic core
solvent and a hydrophilic core solvent. Namely, the amount of the
hydrophilic solvent and the hydrophobic solvent is 100% by weight
of the microcapsule core. The hydrophilic core solvent has a water
solubility of 1 to 100 g/L, a weighted Hansen solubility parameter
of 18 or greater, a Hansen polarizability of 4 or greater, and a
Hansen h-bonding value of 5 or greater; and the hydrophobic core
solvent has a weighted Hansen solubility parameter of 18 or less, a
Hansen polarizability of 4 or less, and a Hansen h-bonding value of
5 or less. The weight ratio between the hydrophobic core solvent
and the hydrophilic core solvent can be in the range of 1:9 to
9:1.
[0009] Examples of the hydrophilic core solvent include, but are
not limited to, triethyl citrate, triacetin, benzyl acetate, ethyl
acetate, propylene glycol, dipropylene glycol, glycol ethers, and
combinations thereof. Exemplary hydrophobic core solvents are
isopropyl myristate, C.sub.5-C.sub.50 (e.g., C.sub.5-C.sub.20 and
C.sub.6-C.sub.15) tryglyceride (e.g., caprylic triglyceride, capric
triglyceride, and a mixture thereof), D-limonene, silicone oil,
mineral oil, and combinations thereof. In some embodiments, the
hydrophobic core solvent contains a fragrance ingredient having a
ClogP of 2 or greater (e.g., 2.5 or greater, 3 or greater, 3.3. or
greater). In other embodiments, the hydrophobic core solvent is
free of any fragrance ingredient. The term "fragrance ingredient"
refers to materials which may be acceptably employed within
fragrances to provide a contribution of an odor, fragrance,
essence, or scent either alone or in combination with other
fragrance ingredients. Typically, such materials will be relatively
volatile, and characterized by molecular weights within the range
of at least 100 g/mol.
[0010] In other embodiments, the microcapsule has a size of 0.1 to
1000 .mu.m in diameter. The weight ratio between the microcapsule
core and the microcapsule wall is preferably in the range of 1:99
to 99:1 (e.g., 1:1 to 50:1, 5:1 to 50:1, and 5:1 to 20:1). Suitable
encapsulating polymers for the microcapsule wall include
polyacrylate, polyurea, polyurethane, polyacrylamide, polyester,
polyether, polyamide, poly(acrylate-co-acrylamide), starch, silica,
gelatin and gum Arabic, alginate, chitosan, polylactide,
poly(melamine-formaldehyde), poly(urea-formaldehyde), and
combinations thereof.
[0011] Another aspect of this invention relates to microcapsule
compositions each comprising any of the microcapsules described
above and a continuous phase that has an external hydrophilic
solvent and an active material, in which the microcapsule wall is
permeable to the active material, the ratio between the
microcapsule core and the active material is 1:99 to 99:1, and the
active material is selected from the group consisting of a
fragrance, pro-fragrance, flavor, malodor counteractive agent,
vitamin or derivative thereof, anti-inflammatory agent, fungicide,
anesthetic, analgesic, antimicrobial active, anti-viral agent,
anti-infectious agent, anti-acne agent, skin lightening agent,
insect repellent, animal repellent, vermin repellent, emollient,
skin moisturizing agent, wrinkle control agent, UV protection
agent, fabric softener active, hard surface cleaning active, skin
or hair conditioning agent, flame retardant, antistatic agent,
taste modulator, cell, probiotic, antioxidant, self-tanning agent,
dihydroxyacetone, cooler, sensate, malodor reactive material,
cosmetic active, and combinations thereof. The active material is
initially outside of the microcapsule wall.
[0012] Nonlimiting exemplary external hydrophilic solvents are
water, ethanol, propanol, dipropylene glycol, propylene glycol,
glycerin, diethyl phthalate, and combinations thereof.
[0013] In some microcapsule compositions, the active material is a
fragrance having a weighted Hansen solubility parameter of 15 to
20, a Hansen polarizability of 5 or less, and a Hansen h-bonding
value of 10 or less. In other microcapsule compositions, the
fragrance contains two or more fragrance ingredients, 50 weight %
or more of the fragrance ingredients have a water solubility of 0.1
g/L or less, 50 weight % or less of the fragrance ingredients have
a vapor concentration of 100 .mu.g/L or less, and 30 weight % or
less of the fragrance ingredients have a CLogP of 3 or less. In
still other microcapsule compositions, the Euclidean difference in
solubility parameter between the fragrance and the hydrophilic core
solvent is less than the Euclidean difference between the fragrance
and the hydrophobic core solvent. In yet other microcapsule
compositions, the Euclidean difference in solubility parameter
between the fragrance and the hydrophobic core solvent is less than
5.
[0014] Any of the microcapsule compositions described above can
further contain a deposition aid such as polyquaternium-4,
polyquaternium-5, polyquaternium-6, polyquaternium-7,
polyquaternium-10, polyquaternium-16, polyquaternium-22,
polyquaternium-24, polyquaternium-28, polyquaternium-39,
polyquaternium-44, polyquaternium-46, polyquaternium-47,
polyquaternium-53, polyquaternium-55, polyquaternium-67,
polyquaternium-68, polyquaternium-69, polyquaternium-73,
polyquaternium-74, polyquaternium-77, polyquaternium-78,
polyquaternium-79, polyquaternium-80, polyquaternium-81,
polyquaternium-82, polyquaternium-86, polyquaternium-88,
polyquaternium-101, polyvinylamine, polyethyleneimine,
polyvinylamine and vinylformamide copolymer, polymer comprising
units derived from polyethylene glycol and terephthalate, and any
combination thereof.
[0015] Also within the scope of this invention is a method of
preparing any one microcapsule compositions described above. The
method includes the steps of: (a) providing a microcapsule that has
a microcapsule core and a microcapsule wall encapsulating the
microcapsule core, in which the microcapsule core contains a
hydrophilic core solvent and/or a hydrophobic core solvent, and the
microcapsule wall is formed of an encapsulating polymer and
permeable to the hydrophilic core solvent; (b) providing a
continuous phase that has an external hydrophilic solvent and an
active material; (c) mixing the microcapsule and the continuous
phase to obtain a microcapsule dispersion; and (d) aging the
microcapsule dispersion to obtain the microcapsule composition.
[0016] Still within the scope of this invention are consumer
products containing any one of the microcapsule compositions
described above. The consumer product can be liquid or semisolid
products such as a baby care product, a diaper rash cream or balm,
a baby powder, a diaper, a bib, a baby wipe, a cosmetic
preparation, a powder foundation, a liquid foundation, an eye
shadow, a lipstick or lip balm, a home care product, an all-purpose
cleaner, a bathroom cleaner, a floor cleaner, a window cleaner, a
plastics polish, a bleach, a toilet cleaner, a toilet rimblock, a
bath tissue, a paper towel, a disposable wipe, liquid air
freshener, air freshener spray, a spray dispenser product, an
incense stick, a rug deodorizer, a candle, a room deodorizer, a
liquid dish detergent, an automatic dish detergent, a powder dish
detergent, a leather detergent, a tablet dish detergent, a paste
dish detergent, a unit dose tablet or capsule, a flavor, a beverage
flavor, a diary flavor, a fruit flavor, a miscellaneous flavor, a
sweet goods flavor, a tobacco flavor, a toothpaste flavor, a
chewing gum, a breath freshener, an orally dissolvable strips, a
chewable candy, a hard candy, an oral care product, a tooth paste,
a toothbrush, a dental floss, an oral rinse, an tooth whitener, a
denture adhesive, a health care device, a tampon, a feminine
napkin, an anti-inflammatory balm, an anti-inflammatory ointment,
an anti-inflammatory spray, a disinfectant, a personal care
product, a soap, a bar soap, a liquid soap, a bath fragrance, a
body wash, a non-aerosol body spray, a body milk, a cleanser, a
body cream, a hand sanitizer, a hand wash, a functional product
base, a sunscreen lotion, a sunscreen spray, a deodorant, an
anti-perspirant, an roll-on product, an aerosol product, a natural
spray product, a wax-based deodorant, a glycol type deodorant, a
soap type deodorant, a facial lotion, a body lotion, a hand lotion,
a miscellaneous lotion, a body powder, a shave cream, a shave gel,
a shave butter, a bath soak, a shower gel, an exfoliating scrub, a
foot cream, a facial tissue, a cleansing wipe, a talc product, a
hair care product, a hair care with ammonia, a shampoo, a hair
conditioner, a hair rinse, a hair refresher, a hair fixative or
styling aid, a hair bleach, a hair dye or colorant, a fabric care
product, a fabric softener, a liquid fabric softener, a fabric
softener sheet, a drier sheet, a fabric refresher, an ironing
water, a detergent, a laundry detergent, a liquid laundry
detergent, a powder laundry detergent, a tablet laundry detergent,
a laundry detergent bar, a laundry detergent cream, a hand wash
laundry detergent, a scent booster, a fragrance, a cologne,
compounds, an encapsulated fragrance, a fine fragrance, a men's
fine fragrance, a women's fine fragrance, a perfume, a solid
perfume, an Eau De Toilette product, a natural spray product, a
perfume spray product, an insect repellent product, and a wildlife
scent.
[0017] An exemplary consumer product is an aerosol product
containing 0.01 to 50% of any one of the above-described
microcapsule compositions.
[0018] Another example is a perfume spray product containing 0.01
to 40% of the microcapsule composition, 0.01 to 40% of a fragrance
as the active material, at least 60% of ethyl alcohol, 0 to 30% of
a suspending polymer, and 0 to 30% of an emollient. The suspending
agent can be polyacrylate crosspolymer-6,
acrylates/C.sub.10-C.sub.30 alkyl acrylate crosspolymer, or a
combination thereof, and the emollient is trilsononanoin,
ethylhexyl isononanoate, cyclopentasiloxane, or a combination
thereof.
[0019] Still another example is an insect repellent containing (i)
2 to 95% (e.g., 2 to 40%, 2 to 20%, 2 to 10%, 4 to 35%, and 5 to
30%) of an insect repellent such as N,N-Diethyl-meta-toluamide
("DEET") and (ii) 1 to 50% (e.g., 2 to 40%, 2 to 30%, 5 to 30%, and
5-20%) of the microcapsule composition. The insect repellent DEET
is used in current consumer products in concentrations from 2% to
100% without microcapsules. A direct correlation is found between
neat DEET concentration and hours of protection against insect
bites. DEET at 100% was found to offer up to 12 hours of
protection. At 20 to 34%, DEET offered 3 to 6 hours of protection.
See Matsuda et al., Journal of the American Mosiquito Control
Association (1996), 12, 69-74.
[0020] The insect repellent product of this invention typically
contains DEET outside of the microcapsule core and (ii) of the
microcapsule composition of this invention. The insect repellent
products of this product offer not only higher repellent
efficiency, but also longer effective time and greater storage
stability as a result of the protection provided by the
microcapsules.
[0021] Note that in the insect repellent compositions of this
invention, the microcapsule has a microcapsule core containing 10
to 90% (e.g., 20 to 80% and 40 to 60%) of a hydrophilic solvent and
90 to 10% (e.g., 80 to 20% and 60 to 40%) of a hydrophobic solvent,
by weight of the microcapsule core. After the formation of a
microcapsule, DEET is added to the microcapsule and adsorbed onto
the microcapsule. In some embodiments, the microcapsule core does
not contain DEET. In other embodiments, the microcapsule core
contains 1 to 30% (e.g., 2 to 20% and 5 to 15%) of DEET by weight
of the microcapsule core.
[0022] In some embodiments, the insect repellent composition
contains a continuous phase (water, an alcohol such as ethanol or
isopropanol, or combination thereof). The microcapsule is dispersed
in the continuous phase. The insect repellent (such as DEET) is
dispersed or dissolved in the continuous phase and the
concentration of DEET outside of the microcapsule core is 2 to 40%
(e.g., 2 to 20%, 2 to 20%, 2 to 10%, and 4 to 20%).
[0023] Accordingly, one aspect of this invention relates to a
method of preparing an insect repellent composition. The method
comprises the step of: (a) providing a microcapsule comprising a
microcapsule wall and a microcapsule core, the microcapsule wall is
formed of an encapsulating polymer described above, and the
microcapsule core contains 10 to 90% (e.g., 20 to 80% and 40 to
60%) of a hydrophilic solvent and 90 to 10% (e.g., 80 to 20% and 60
to 40%) of a hydrophobic solvent, by weight of the microcapsule
core; and (b) adding an insect repellent active such as
N,N-Diethyl-meta-toluamide to the microcapsule to obtain the insect
repellent composition of this invention. Preferably, the amount of
the hydrophilic solvent and the hydrophobic solvent is 100% by
weight of the microcapsule core.
[0024] All parts, percentages and proportions refer to herein and
in the claims are by weight unless otherwise indicated.
[0025] The values and dimensions disclosed herein are not to be
understood as being strictly limited to the exact numerical values
recited. Instead, unless otherwise specified, each such value is
intended to mean both the recited value and a functionally
equivalent range surrounding that value. For example, a value
disclosed as "50%" is intended to mean "about 50%."
[0026] The terms "capsule" and "microcapsule" are used
interchangeably.
[0027] The terms "g," "mg," and ".mu.g" refer to "gram,"
"milligram," and "microgram," respectively. The terms "L" and "mL"
refer to "liter" and "milliliter," respectively.
[0028] The term "Hansen solubility parameter" refers to a
solubility parameter approach proposed by Charles Hansen used to
predict polymer solubility and was developed around the basis that
the total energy of vaporization of a liquid consists of several
individual parts. To calculate the "weighted Hansen solubility
parameter" one must combine the effects of (atomic) dispersion
forces, (molecular) permanent dipole-permanent dipole forces, and
(molecular) hydrogen bonding (electron exchange). The weighted
Hansen solubility parameter" is calculated as
(.delta.D.sup.2+.delta.P.sup.2+.delta.H.sup.2).sup.0.5, wherein
.delta.D is the Hansen dispersion value, .delta.P is the Hansen
polarizability value, and .delta.H is the Hansen Hydrogen-bonding
("h-bonding") value. For a more detailed description of the
parameters and values, see Charles Hansen, The Three Dimensional
Solubility Parameter and Solvent Diffusion Coefficient, Danish
Technical Press (Copenhagen, 1967).
[0029] Euclidean difference in solubility parameter between a
fragrance and a solvent is calculated as
(4*(.delta.D.sub.solvent-.delta.D.sub.fragrance).sup.2
(.delta.P.sub.solvent-.delta..sub.fragrance).sup.2+(.delta.H.sub.solvent--
.delta..sub.fragrance).sup.2).sup.0.5, in which
.delta.D.sub.solvent, .delta.P.sub.solvent, solvent, and
.delta.H.sub.solvent are the Hansen dispersion value, Hansen
polarizability value, and Hansen h-bonding values of the solvent,
respectively; and .delta.D.sub.fragrance, .delta.P.sub.fragrance,
and .delta.H.sub.fragrance are the Hansen dispersion value, Hansen
polarizability value, and Hansen h-bonding values of the fragrance,
respectively.
[0030] The details of one or more embodiments of the invention are
set forth in the description below. Other features, objects, and
advantages will be apparent from the description and the
claims.
DETAILED DESCRIPTION
[0031] It has been found that reloadable microcapsules formulated
with a hydrophilic solvent unexpectedly improved substantivity of
an active material (e.g., fragrance) not initially encapsulated in
the microcapsules.
[0032] These microcapsules each have (i) a microcapsule wall
permeable to both the hydrophilic core solvent and the active
material (e.g., a fragrance) and (ii) a microcapsule core
containing the hydrophilic core solvent alone or in combination
with a hydrophobic core solvent. In a preferred embodiment, the
microcapsule core consists of a hydrophilic solvent and a
hydrophobic solvent and is free of an active material.
[0033] The reloadable microcapsule is then formulated with an
active material in an external hydrophilic solvent. The hydrophilic
core solvent is believed to diffuse from the microcapsule core to
the external hydrophilic solvent and create a void in the
microcapsule core. The active material diffuses in an opposite
direction, i.e., from the external hydrophilic solvent to the void
in the microcapsule core, thus affording a microcapsule composition
without the need to encapsulating the active material during the
preparation of the reloadable microcapsule.
[0034] Such a microcapsule composition is shown to be an effective
delivery system capable of delivering a fragrance with enhanced
longevity in an alcohol based carrier. By preparing a reloadable
microcapsule without a fragrance, the delivery system can later
incorporate a fragrance of choice into the reloadable microcapsule
for a specific application. Thus, significant economies of scale
and enhancements of creative flexibility can be achieved.
[0035] The microcapsule composition can assist the delivery of
fragrance components with low substantivity, thereby expanding the
fragrance pallet. The term substantivity refers to the property of
the encapsulated fragrance to be retained on a solid surface (such
as skin, hair, laundry, furniture, and floor) for a prolonged
period of time.
[0036] The microcapsule composition also allows for the delivery of
fragrance components with functional groups such as aldehydes and
primary alcohols, which would otherwise react with capsule wall
materials. These functional groups are indeed common in fragrances
as well as other active materials.
[0037] Further, the microcapsule composition also has applicability
in applications such as skin care products where topical
substantivity of a hydrophobic semi-volatile skin care active is
needed. Some non-limiting examples include sunscreens, topical
analgesics, antibacterial agents, and combinations thereof.
[0038] Also envisioned is the ability of the microcapsule
composition to enhance substantivity and release of a semi-volatile
active in other applications such as cosmetics, pesticides, insect
repellents, herbicides, and pheromone baits for pest control.
[0039] The microcapsule composition delivery system also find its
utility in a wide range of consumer applications, e.g., personal
care products including shampoos, hair conditioners, hair rinses,
hair refreshers; personal wash such as bar soaps, body wash,
personal cleaners and sanitizers; fabric care such as fabric
refreshers, softeners and dryer sheets, ironing water, industrial
cleaners, liquid and powder detergent including unit dose capsules,
rinse conditioners, and scent booster products; fine fragrances
such as body mist and Eau De Toilette products; deodorants; roll-on
products, and aerosol products. A specific consumer product is an
alcohol deodorant spray product.
[0040] Not to be bound by any theory, it is believed that, when
mixing a reloadable microcapsule with an active material in an
external hydrophilic solvent, the hydrophilic core solvent diffuses
from the core to the external hydrophilic solvent, making space for
the active material to diffuse from the external hydrophilic
solvent to the microcapsule core until the equilibrium is
reached.
[0041] The microcapsule wall has pores or channels making the wall
permeable to both the hydrophilic core solvent and the active
material. Permeability also relates to the thickness of the wall,
which can be controlled or manipulated by the weight ratio between
the microcapsule core and the microcapsule wall forming materials.
This weight ratio can be 100:1 to 1:1 (e.g., 50:1 to 5:1 and 40:1
to 8:1). By using a higher ratio (namely more microcapsule core
than microcapsule wall-forming materials), the microcapsule wall
becomes thinner and is more permeable.
[0042] The microcapsule wall is formed of an encapsulating polymer
that can be polyurea, polyurethane, alginate, gelatin, urea
formaldehyde, melamine formaldehyde, acrylate hydrogel,
polylactide, chitosan, silica, or a combination thereof.
[0043] Turning to the microcapsule core, it contains a hydrophilic
core solvent. The water solubility of this solvent can be 0.02 to
300 g/L, preferably 0.1 to 200 g/L, and more preferably 1 to 100
g/L.
[0044] The hydrophilic core solvent typically has a weighted Hansen
solubility parameter of 18 or greater, a Hansen polarizability
(.delta.P) of 4 or greater, and a Hansen h-bonding value (.delta.H)
of 5 or greater.
[0045] Preferably, the hydrophilic core solvent has a vapor
concentration at 25.degree. C. of 4.6 .mu.g/L or greater. The vapor
concentration of a solvent refers to the mass of the solvent vapor
present per unit volume of air expressed in micrograms per liter
(.mu.g/L) at a standard atmosphere (atm). The vapor concentrations
of various solvent are available from reference materials such as
the CRC Handbook of Chemistry and Physics, 98.sup.th Edition (CRC
Press 2017). The vapor concentration can be determined by ASTM D323
or ASTM D4953.
[0046] Exemplary hydrophilic core solvents are triethyl citrate,
triacetin, benzyl acetate, ethyl acetate, propylene glycol,
dipropylene glycol, and combinations thereof. More examples include
glycol ethers such as ethylene glycol monomethyl ether, ethylene
glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene
glycol monoisopropyl ether, ethylene glycol monobutyl ether,
ethylene glycol monophenyl ether, ethylene glycol monobenzyl ether,
diethylene glycol monomethyl ether, diethylene glycol monoethyl
ether, diethylene glycol mono-n-butyl ether, ethylene glycol
dimethyl ether, ethylene glycol diethyl ether, ethylene glycol
dibutyl ether, and combinations thereof.
[0047] Besides the hydrophilic core solvent, the microcapsule core
can also contain a hydrophobic core solvent having a weighted
Hansen solubility parameter of 18 or less, a Hansen polarizability
(.delta.P) value of 4 or less, and a Hansen h-bonding value
(.delta.H) of 5 or less. Preferably, the hydrophobic core solvent
has a vapor concentration at 25.degree. C. of 0.1 .mu.g/L or
less.
[0048] These hydrophobic solvents, being nonvolatile (i.e., having
a boiling point of 100.degree. C. or higher), are added to modify
the hydrophilicity/hydrophobicity of the microcapsule core solvents
for optimized fragrance diffusion. In some embodiments, hydrophobic
solvents are used to increase the compatibility of various active
materials, increase the overall hydrophobicity of the core
solvents, influence the vapor pressure, or serve to structure the
mixture. Suitable solvents include those having reasonable affinity
for the active materials and a ClogP greater than 2.5, preferably
greater than 3.5 and more preferably greater than 5.5. It should be
noted that selecting a solvent and active material with high
affinity for each other will result in improvement in stability.
Exemplary solvents are triglyceride oil, mono and diglycerides,
mineral oil, silicone oil, diethyl phthalate, polyalpha olefins,
castor oil, isopropyl myristate, mono-, di- and tri-esters and
mixtures thereof, fatty acids, and glycerine. The fatty acid chain
can range from C.sub.4-C.sub.26 and can have any level of
unsaturation. For instance, one of the following solvents can be
used: capric/caprylic triglyceride known as NEOBEE M5 (Stepan
Corporation); the CAPMUL series by Abitec Corporation (e.g., CAPMUL
MCM); isopropyl myristate; fatty acid esters of polyglycerol
oligomers, e.g.,
R.sup.2CO--[OCH.sub.2--CH(OCOR.sup.1)--CH.sub.2O-].sub.n, where
R.sup.1 and R.sup.2 can be H or C.sub.4-C.sub.26 aliphatic chains,
or mixtures thereof, and n ranges between 2 and 50, preferably 2
and 30; nonionic fatty alcohol alkoxylates like the NEODOL
surfactants by BASF; the dobanol surfactants by Shell Corporation
or the BIO-SOFT surfactants by Stepan, wherein the alkoxy group is
ethoxy, propoxy, butoxy, or mixtures thereof and said surfactants
can be end-capped with methyl groups in order to increase their
hydrophobicity; di- and tri-fatty acid chain containing nonionic,
anionic and cationic surfactants, and mixtures thereof; fatty acid
esters of polyethylene glycol, polypropylene glycol, and
polybutylene glycol, or mixtures thereof; polyalphaolefins such as
the EXXONMOBIL PURESYM PAO line; esters such as the EXXONMOBIL
PURESYN esters; mineral oil; silicone oils such polydimethyl
siloxane and polydimethylcyclosiloxane; diethyl phthalate; di-octyl
adipate and di-isodecyl adipate. In certain embodiments, ester oils
have at least one ester group in the molecule. One type of common
ester oil useful in the present invention are the fatty acid mono
and polyesters such as cetyl octanoate, octyl isonanoanate,
myristyl lactate, cetyl lactate, isopropyl myristate, myristyl
myristate, isopropyl palmitate, isopropyl adipate, butyl stearate,
decyl oleate, cholesterol isostearate, glycerol monostearate,
glycerol distearate, glycerol tristearate, alkyl lactate, alkyl
citrate and alkyl tartrate; sucrose ester and polyesters, sorbitol
ester, and the like. A second type of useful ester oil is
predominantly composed of triglycerides and modified triglycerides.
These include vegetable oils such as jojoba, soybean, canola,
sunflower, safflower, rice bran, avocado, almond, olive, sesame,
persic, castor, coconut, and mink oils. Synthetic triglycerides can
also be employed provided they are liquid at room temperature.
Modified triglycerides include materials such as ethoxylated and
maleated triglyceride derivatives provided they are liquids.
Proprietary ester blends such as those sold by FINETEX as FINSOLV
are also suitable, as is ethylhexanoic acid glyceride. A third type
of ester oil is liquid polyester formed from the reaction of a
dicarboxylic acid and a diol. Examples of polyesters suitable for
the present invention are the polyesters marketed by EXXONMOBIL
under the trade name PURESYN ESTER. Preferred examples are
isopropyl myristate, C.sub.5-C.sub.50 tryglycerides (e.g., caprylic
(C.sub.8) triglyceride, capric (C.sub.10) triglyceride, and a
mixture thereof), D-limonene, silicone oil, and combinations
thereof.
[0049] The ratio between the hydrophobic core solvent and the
hydrophilic core solvent is 1:9 to 9:1 (e.g., 1:4 to 4:1 and 2:3 to
3:2). By way of illustration, the microcapsule core contains by
weight a hydrophobic core solvent 10-90% (e.g., 20-80% and 40-60%)
and a hydrophilic core solvent 10-90% (e.g., 20-80% and 40-60%),
provided that the sum of the hydrophobic core solvent and the
hydrophilic core solvent is 100% by weight of the microcapsule
core.
[0050] The microcapsule core can also contains a primary or
secondary alcohol or thiol having (i) a molecular weight of 32 to
500 (e.g., 46 to 400, and 46 to 300), (ii) the number of carbon
atoms of 1 to 25 (e.g., 2 to 20), or (iii) a ClogP of -2 or greater
(0 or greater and 2 or greater). The amount of the alcohol or thiol
is 0.001 to 2% of the microcapsule composition. Examples include
saturated and unsaturated, branched and linear, C.sub.6-C.sub.10
non-fatty alcohols; saturated and unsaturated, branched and linear
C.sub.11-C.sub.24 fatty alcohols; ethoxylated, propoxylated, and
butoxylated fatty alcohols, with single OH end groups; Guerbet
alcohols such as 2-ethylhexanol and 2-heptylundecanol; Castor oil
(including ricinoleic acid and its esters); Lanolin; geraniol;
citronellol; isostearyl alcohol; C.sub.8 alcohol; and any
combinations thereof.
[0051] When the reloadable microcapsule is dispersed in an external
hydrophilic solvent, the hydrophilic core solvent diffuses to the
external hydrophilic solvent as the affinity between the external
hydrophilic solvent and the hydrophilic core solvent is greater
than the affinity between the hydrophobic core solvent and the
hydrophilic core solvent. The affinity is related to the Euclidean
difference in solubility parameter described above. A small
Euclidean difference indicates a strong affinity.
[0052] An active material (e.g., a fragrance) is present in the
external hydrophilic solvent. In some embodiments, the active
material has an affinity for the hydrophobic core solvent greater
than that for either the hydrophilic core solvent or the external
hydrophilic solvent, so that the active material is prone to
diffuse into the microcapsule core.
[0053] In other embodiments, the active material has a weighted
Hansen solubility parameter of 20 or less (e.g., 15-20), a Hansen
polarizability (.delta.P) value of 5 or less, and a Hansen
h-bonding value (.delta.H) of 10 or less (e.g., 9 or less and 8 or
less).
[0054] The active material can have a water solubility 0.2 g/L or
less (e.g., 0.1 g/L or less) and/or a vapor concentration at
25.degree. C. of 100 .mu.g/L or more (i.e., the concentration of
the vapor of the ingredient in the air to which it evaporates).
When the active material is a fragrance containing multiple
fragrance ingredients, 50 wt % or more (i.e., 50-100 wt %) of the
fragrance ingredients has a water solubility of 0.1 g/L or less
and/or 50 wt % or less (i.e., 0-50 wt %) of the fragrance
ingredients has a vapor concentration of 100 .mu.g/L or less.
[0055] Typically, the active material (such as a fragrance) has a
vapor concentration at 25.degree. C. of 100 .mu.g/L or greater,
preferably 800 .mu.g/L or greater.
[0056] Preferred active materials have a molecular volume of 200
nm.sup.3 or more. Molecular volume is defined as the molecular mass
divided by the corresponding molecular density. It is a measure of
the volume occupied by a molecule (or scaled by moles, the volume
occupied by a mole of molecules) condensed phase at room
temperature and at a standard atmosphere pressure. The molecular
mass and the molecular density of fragrance chemicals are available
from reference materials such as the CRC Handbook of Chemistry and
Physics, 98.sup.th Edition (CRC Press 2017). These data are also
available in the database developed by J. Baker, M. Douma, and S.
Kotochigoua: the National Institute of Standards and Technology
WebBook, Gathersburd, Md. 20899.
[0057] The active material can be present by weight of the
microcapsule composition at a level of 0.005 to 30% (e.g., 0.01 to
20%, 0.05 to 15%, 5 to 30%, and 5 to 20%).
[0058] The weight ratio between the hydrophilic core solvent and
the hydrophobic core solvent can range from 1:99 to 99:1 (e.g.,
10:90 to 90:10, 30:70 to 70:30, and 40:60 to 60:40).
[0059] The microcapsule wall is formed of an encapsulating polymer.
Examples of the encapsulating polymer include polyacrylate,
polyurea, polyurethane, polyacrylamide, polyester, polyether,
polyamide, poly(acrylate-co-acrylamide), starch, silica, gelatin
and gum Arabic, alginate, chitosan, polylactide,
poly(melamine-formaldehyde), poly(urea-formaldehyde), and
combinations thereof.
[0060] A specific exemplary encapsulating polymer is polyurea,
which is typically a product of the polymerization reaction of a
polyisocyanate and a polyamine in the presence of a dispersant such
as polyvinyl alcohol, condensed naphthalene sulfonate, and a
combination thereof. Either aromatic polyisocyanates or aliphatic
polyisocyanates can be used. Suitable aromatic polyisocyanates
include those containing a phenyl, tolyl, xylyl, naphthyl, or
diphenyl moiety, or a combination thereof. Examples are
polyisocyanurates of toluene diisocyanate, trimethylol
propane-adducts of toluene diisocyanate, methylene diphenyl
diisocyanate, and trimethylol propane-adducts of xylylene
diisocyanate. Suitable aliphatic polyisocyanates include a
symmetric or asymmetric trimer of hexamethylene diisocyanate, a
dimer of hexamethylene diisocyanate, a trimer of isophorone
diisocyanate, a biuret of hexamethylene diisocyanate, and a
combination thereof.
[0061] Suitable polyamines include hexamethylene diamine ("HMDA"),
hexaethylenediamine, ethylenediamine, 1,3-diaminopropane,
1,4-diamino-butane, diethylenetriamine, pentaethylenehexamine,
bis(3-aminopropyl)amine, bis(hexanethylene)triamine,
tris(2-aminoethyl)amine, triethylene-tetramine,
N,N'-bis(3-aminopropyl)-1,3-propanediamine, tetraethylenepentamine,
branched polyethylenimine, chitosan, nisin, gelatin,
1,3-diamino-guanidine, 1,1-dimethylbiguanide, guanidine, arginine,
lysine, ornithine, and a combination thereof.
[0062] The weight ratio between the polyisocyanate and the
polyamine (e.g., HMDA) can be in the range of 99:1 to 1:99 (e.g.,
50:1 to 1:50 and 20:1 to 20:1).
[0063] More microcapsule wall materials are described below and can
also be found in publications such as U.S. Pat. No. 7,196,049, US
2014/0044760, WO 2014/011860, WO 2014/059087, WO 2016/049456, WO
2015/023961, and WO 2014/085287.
[0064] The reloadable microcapsule thus prepare typically has a
particle size in the range of from 0.1 to 1000 microns (i.e.,
.mu.m) in diameter (e.g., 0.5 to 500 microns, 1 to 200 microns, 2
to 50 microns, 5 to 25 microns, and 1 to 10 microns). The capsule
size distribution can be narrow, broad, or multi-modal.
1. Microcapsule Delivery Systems
[0065] Reloadable microcapsules can be prepared following
encapsulation procedures known in the art, except that the active
material is not encapsulated in the procedures. See for example
U.S. Pat. Nos. 5,112,688, 6,329,057, and 6,261,483. Wall forming
materials (i.e., encapsulating polymers) include a melamine
formaldehyde, polyurethane, polysiloxanes, polyurea, polyamide,
polyimide, polyvinyl alcohol, polyanhydride, polyolefin,
polysulfone, polysaccharide, protein, polypeptide, polylactide
(PLA), polyglycolide (PGA), polyorthoester, polyphosphazene,
silicone, lipid, modified cellulose, gum, polystyrene, polyester,
polyether, and combination of these materials. Other polymeric
materials that are functional are ethylene maleic anhydride
copolymer, styrene maleic anhydride copolymer, ethylene vinyl
acetate copolymer, and lactide glycolide copolymer. Biopolymers
that are derived from alginate, chitosan, collagen, dextran,
gelatin, and starch can also be used as the encapsulating
materials. Additionally, capsules can be made via the simple or
complex coacervation of gelatin. Preferred encapsulating wall
polymers include those formed from isocyanates, acrylates,
acrylamide, acrylate-co-acrylamide, hydrogel monomers, sol-gel
precursors, gelatin, melamine-formaldehyde or urea-formaldehyde
condensates, as well as similar types of aminoplasts.
[0066] Certain specific encapsulating polymers are described below
as non-limiting examples.
1.1 Polyurea/Polyurethane Capsules
[0067] Polyurea capsules each have a microcapsule wall formed of an
encapsulating polymer that is the polymerization reaction product
of a polyisocyanate and a polyamine/polyalcohol. See WO
2004/054362; WO 2015/023961; and U.S. Pat. Nos. 6,340,653 and
8,299,011. In addition, the encapsulating polymer can also be
prepared using a carbonyl crosslinker and a
polyamine/polyalcohol.
[0068] 1.1.1 Polyisocyanates
[0069] The polyisocyanates each contain two or more isocyanate
(--NCO) groups. Suitable polyisocyanates include, for example,
1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate
(MDI), hydrogenated MDI (H12MDI), xylylene diisocyanate (XDI),
tetramethylxylol diisocyanate (TMXDI), 4,4'-diphenyldimethylmethane
diisocyanate, di- and tetraalkyldiphenylmethane diisocyanate,
4,4'-dibenzyl diisocyanate, 1,3-phenylene diisocyanate,
1,4-phenylene diisocyanate, the isomers of tolylene diisocyanate
(TDI), optionally in a mixture,
1-methyl-2,4-diisocyanatocyclohexane,
1,6-diisocyanato-2,2,4-trimethylhexane,
1,6-diisocyanato-2,4,4-trimethylhexane,
1-isocyanatomethyl-3-isocyanato-1,5,5-trimethylcyclohexane,
chlorinated and brominated diisocyanates, phosphorus-containing
diisocyanates, 4,4'-diisocyanatophenylperfluoroethane,
tetramethoxybutane 1,4-diisocyanate, butane 1,4-diisocyanate,
hexane 1,6-diisocyanate (HDI), dicyclohexylmethane diisocyanate,
cyclohexane 1,4-diisocyanate, ethylene diisocyanate, phthalic acid
bisisocyanatoethyl ester, also polyisocyanates with reactive
halogen atoms, such as 1-chloromethylphenyl 2,4-diisocyanate,
1-bromomethylphenyl 2,6-diisocyanate, and 3,3-bischloromethyl ether
4,4'-diphenyldiisocyanate. Sulfur-containing polyisocyanates are
obtained, for example, by reacting hexamethylene diisocyanate with
thiodiglycol or dihydroxydihexyl sulfide. Further suitable
diisocyanates are trimethylhexamethylene diisocyanate,
1,4-diisocyanatobutane, 1,2-diisocyanatododecane, dimer fatty acid
diisocyanate, and combinations thereof.
[0070] Other suitable commercially-available polyisocyanates
include LUPRANATE M20 (PMDI, commercially available from BASF
containing isocyanate group "NCO" 31.5 wt %), where the average n
is 0.7; BAYHYDUR N304 and BAYHYDUR N305, which are aliphatic
water-dispersible polyisocyanates based on hexamethylene
diisocyanate; DESMODUR N3600, DESMODUR N3700, and DESMODUR N3900,
which are low viscosity, polyfunctional aliphatic polyisocyanates
based on hexamethylene diisocyanate; DESMODUR 3600 and DESMODUR
N100 which are aliphatic polyisocyanates based on hexamethylene
diisocyanate, commercially available from Bayer Corporation,
Pittsburgh, Pa.; PAPI 27 (PMDI commercially available from Dow
Chemical having an average molecular weight of 340 and containing
NCO 31.4 wt %) where the average n is 0.7; MONDUR MR (PMDI
containing NCO at 31 wt % or greater, commercially available from
Bayer) where the average n is 0.8; MONDUR MR Light (PMDI containing
NCO 31.8 wt %, commercially available from Bayer) where the average
n is 0.8; MONDUR 489 (PMDI commercially available from Bayer
containing NCO 30-31.4 wt %) where the average n is 1.0;
poly[(phenylisocyanate)-co-formaldehyde] (Aldrich Chemical,
Milwaukee, Wis.), other isocyanate monomers such as DESMODUR N3200
(poly(hexamethylene diisocyanate) commercially available from
Bayer), and TAKENATE D110-N (xylene diisocyanate adduct polymer
commercially available from Mitsui Chemicals corporation, Rye
Brook, N.Y., containing NCO 11.5 wt %), DESMODUR L75 (a
polyisocyanate base on toluene diisocyanate commercially available
from Bayer), and DESMODUR IL (another polyisocyanate based on
toluene diisocyanate commercially available from Bayer).
[0071] In some embodiments, the polyisocyanate used in the
preparation of the capsules of this invention is a single
polyisocyanate. In other embodiments the polyisocyanate is a
mixture of polyisocyanates. In some embodiments, the mixture of
polyisocyanates includes an aliphatic polyisocyanate and an
aromatic polyisocyanate. In particular embodiments, the mixture of
polyisocyanates is a biuret of hexamethylene diisocyanate and a
trimethylol propane-adduct of xylylene diisocyanate. In certain
embodiments, the polyisocyanate is an aliphatic isocyanate or a
mixture of aliphatic isocyanate, free of any aromatic isocyanate.
In other words, in these embodiments, no aromatic isocyanate is
used to prepare the polyurea/polyureathane polymers as capsule wall
materials.
[0072] The average molecular weight of certain suitable
polyisocyanates varies from 250 to 1000 Da and preferable from 275
to 500 Da. In general, the range of the polyisocyanate
concentration varies from 0.1% to 10%, preferably from 0.1% to 8%,
more preferably from 0.2 to 5%, and even more preferably from 1.5%
to 3.5%, all based on the weight of the capsule delivery
system.
[0073] 1.1.2 Carbonyl Crosslinker
[0074] The carbonyl crosslinkers each have at least two functional
groups, e.g., a first functional group and a second functional
group.
[0075] The first functional group is an electrophilic group
reactive towards the polyfunctional amine or the polyfunctional
alcohol to form a network of the encapsulating polymer. Examples
include formyl, keto, carboxyl, a carboxylate ester group, an acyl
halide group, an amide group, a carboxylic anhydride group, an
alkyl halide group, an epoxide group, an aziridine group, an
oxetane group, an azetidine group, a sulfonyl halide group, a
chlorophosphate group, an isocyanate group, an
.alpha.,.beta.-unsaturated carbonyl group, an
.alpha.,.beta.-unsaturated nitrile group, or an
.alpha.,.beta.-unsaturated methanesulfonyl group. Preferably, the
first function group is a carbonyl electrophilic group containing a
carbonyl group such as formyl, keto, carboxyl, a carboxylate ester
group, an acyl halide group, an amide group, a carboxylic anhydride
group, an .alpha.,.beta.-unsaturated carbonyl group, a
trifluoromethanesulfonate group, and a p-toluenesulfonate
group.
[0076] The second functional group is an electrophilic group
reactive towards the polyfunctional amine or the polyfunctional
alcohol. It can be selected from the groups listed immediately
above.
[0077] Examples of a carbonyl crosslinker include glutaric
dialdehyde, succinic dialdehyde, and glyoxal; as well as compounds
such as glyoxyl trimer and paraformaldehyde, bis(dimethyl) acetal,
bis(diethyl) acetal, polymeric dialdehydes, such as oxidized
starch. Preferably the cross-linking agent is a low molecular
weight, difunctional aldehyde, such as glyoxal, 1,3-propane
dialdehyde, 1,4-butane dialdehyde, 1,5-pentane dialdehyde, or
1,6-hexane.
[0078] 1.1.3 Polyfunctional Amines
[0079] Suitable polyfunctional amines include those described in WO
2015/023961. Examples are hexamethylenediamine,
hexaethylenediamine, ethylenediamine, 1,3-diaminopropane,
1,4-diamino-butane, diethylenetriamine, pentaethylenehexamine,
bis(3-aminopropyl)amine, bis(hexanethylene)triamine,
tris(2-aminoethyl)amine, triethylene-tetramine,
N,N'-bis(3-aminopropyl)-1,3-propanediamine, tetraethylenepentamine,
amino-2-methyl-1-propanol, chitosan, 1,3-diamino-guanidine,
1,1-dimethylbiguanide, guanidine, arginine, lysine, histidine,
ornithine, nisin, gelatin, and combinations thereof.
[0080] Other suitable polyamines include polyethylenimine and
branched polyethylenimine ("BPEI"). Representative BPEI structure
is shown below:
##STR00001##
in which n is an integer from 1 to 20,000 (e.g., 1 to 10,000, 2 to
5,000, and 2 to 1,000). BPEI for use in this invention preferably
has a molecular weight of 500 to 5,000,000 Daltons (e.g., 500 to
1,000,000 Daltons, 750 to 500,000 Daltons, 750 to 100,000 Daltons,
and 750 to 50,000 Daltons).
[0081] BPEI are commercially available from Sigma-Aldrich (St.
Louis, Mo.; average molecular weight 25,000 Daltons) and
Polysciences Inc. (Warrington, Pa.; various products having
molecular weight of 600, 1200, 1800, 10,000, 70,000, 750,000,
250,000, and 2,000,000 Daltons).
[0082] 1.1.4 Polyfunctional Alcohols
[0083] Suitable polyfunctional alcohols are also described in WO
2015/023961. Examples include pentaerythritol, dipentaerythritol,
glycerol, polyglycerol, ethylene glycol, polyethylene glycol,
trimethylolpropane, neopentyl glycol, sorbitol, erythritol,
threitol, arabitol, xylitol, ribitol, mannitol, galactitol,
fucitol, iditol, inositol, volemitol, isomalt, maltitol, lactitol,
maltotriitol, maltotetraitol, polyglycitol, and combinations
thereof.
1.2 Aminoplast and Gelatin Microcapsules
[0084] A representative process used for aminoplast encapsulation
is disclosed in US 2007/0078071, though it is recognized that many
variations with regard to materials and process steps are possible.
Another encapsulation process, i.e., gelatin encapsulation, is
disclosed in U.S. Pat. No. 2,800,457. Both processes are discussed
in the context of fragrance encapsulation for use in consumer
products in U.S. Pat. Nos. 4,145,184 and 5,112,688 respectively.
Polymer systems are well-known in the art and non-limiting examples
of these include aminoplast capsules and encapsulated particles as
disclosed in Application GB 2006709 A; the production of
micro-capsules having walls comprising styrene-maleic anhydride
reacted with melamine-formaldehyde precondensates as disclosed in
U.S. Pat. No. 4,396,670; an acrylic acid-acrylamide copolymer,
cross-linked with a melamine-formaldehyde resin as disclosed in
U.S. Pat. No. 5,089,339; capsules composed of cationic
melamine-formaldehyde condensates as disclosed in U.S. Pat. No.
5,401,577; melamine formaldehyde microencapsulation as disclosed in
U.S. Pat. No. 3,074,845; amido-aldehyde resin in-situ polymerized
capsules (see EP 0 158 449 A1); etherified urea-formaldehyde
polymers (see U.S. Pat. No. 5,204,185); melamine-formaldehyde
microcapsules as described in U.S. Pat. No. 4,525,520; cross-linked
oil-soluble melamine-formaldehyde precondensates as described in
U.S. Pat. No. 5,011,634; capsule wall material formed from a
complex of cationic and anionic melamine-formaldehyde
precondensates that are then cross-linked as disclosed in U.S. Pat.
No. 5,013,473; polymeric shells made from addition polymers such as
condensation polymers, phenolic aldehydes, urea aldehydes or
acrylic polymers as disclosed in U.S. Pat. No. 3,516,941;
urea-formaldehyde capsules as disclosed in EP 0 443 428 A2;
melamine-formaldehyde chemistry as disclosed in GB 2 062 570 A; and
capsules composed of polymer or copolymer of styrene sulfonic acid
in acid of salt form, and capsules cross-linked with
melamine-formaldehyde as disclosed in U.S. Pat. No. 4,001,140.
[0085] Urea-formaldehyde and melamine-formaldehyde pre-condensate
microcapsule shell wall precursors are prepared by means of
reacting urea or melamine with formaldehyde where the mole ratio of
melamine or urea to formaldehyde is in the range of from about 10:1
to about 1:6, preferably from about 1:2 to about 1:5. For purposes
of practicing this invention, the resulting material has a
molecular weight in the range of from 156 to 3000. The resulting
material may be used `as-is` as a cross-linking agent for the
aforementioned substituted or un-substituted acrylic acid polymer
or copolymer or it may be further reacted with a C.sub.1-C.sub.6
alcohol, e.g., methanol, ethanol, 2-propanol, 3-propanol,
1-butanol, 1-pentanol or 1-hexanol, thereby forming a partial ether
where the mole ratio of melamine/urea:formaldehyde:alcohol is in
the range of 1:(0.1-6):(0.1-6). The resulting ether
moiety-containing product may be used `as-is` as a cross-linking
agent for the aforementioned substituted or un-substituted acrylic
acid polymer or copolymer, or it may be self-condensed to form
dimers, trimers and/or tetramers which may also be used as
cross-linking agents for the aforementioned substituted or
un-substituted acrylic acid polymers or co-polymers. Methods for
formation of such melamine-formaldehyde and urea-formaldehyde
pre-condensates are set forth in U.S. Pat. Nos. 3,516,846 and
6,261,483, and Lee et al. (2002) J. Microencapsulation 19,
559-569.
[0086] Examples of urea-formaldehyde pre-condensates useful in the
practice of this invention are URAC 180 and URAC 186, trademarks of
Cytec Technology Corp. of Wilmington, Del. Examples of
melamine-formaldehyde pre-condensates useful in the practice if
this invention, include, but are not limited to, CYMEL U-60, CYMEL
U-64 and CYMEL U-65, trademarks of Cytec Technology Corp. of
Wilmington, Del. It is preferable to use, as the precondensate for
cross-linking, the substituted or un-substituted acrylic acid
polymer or co-polymer. In practicing this invention, the range of
mole ratios of urea-formaldehyde
precondensate/melamine-formaldehyde pre-condensate to
substituted/un-substituted acrylic acid polymer/co-polymer is in
the range of from about 9:1 to about 1:9, preferably from about 5:1
to about 1:5 and most preferably from about 2:1 to about 1:2.
[0087] In one embodiment, microcapsules with polymer(s) composed of
primary and/or secondary amine reactive groups or mixtures thereof
and cross-linkers can also be used. See US 2006/0248665. The amine
polymers can possess primary and/or secondary amine functionalities
and can be of either natural or synthetic origin. Amine-containing
polymers of natural origin are typically proteins such as gelatin
and albumen, as well as some polysaccharides. Synthetic amine
polymers include various degrees of hydrolyzed polyvinyl
formamides, polyvinylamines, polyallyl amines and other synthetic
polymers with primary and secondary amine pendants. Examples of
suitable amine polymers are the LUPAMIN series of polyvinyl
formamides available from BASF. The molecular weights of these
materials can range from 10,000 to 1,000,000 Daltons.
[0088] Urea-formaldehyde or melamine-formaldehyde capsules can also
include formaldehyde scavengers, which are capable of binding free
formaldehyde. When the capsules are for use in aqueous media,
formaldehyde scavengers such as sodium sulfite, melamine, glycine,
and carbohydrazine are suitable. When the capsules are aimed to be
used in products having low pH, e.g., fabric care conditioners,
formaldehyde scavengers are preferably selected from beta
diketones, such as beta-ketoesters, or from 1,3-diols, such as
propylene glycol. Preferred beta-ketoesters include
alkyl-malonates, alkyl aceto acetates and polyvinyl alcohol aceto
acetates.
1.3 Sol-Gel Microcapsules
[0089] Sol-gel microcapsules each have a sol-gel polymer as the
encapsulating polymer. The sol-gel polymer is the polymerization
product of a sol-gel precursor, a compound capable of forming a
sol-gel polymer. The sol-gel precursors are typically those
containing silicon, boron, aluminum, titanium, zinc, zirconium, and
vanadium. Preferred precursors are organosilicon, organoboron,
organoaluminum including metal alkoxides and b-diketonates, and
combinations thereof. See U.S. Pat. No. 9,532,933.
1.4 Hydrogel Microcapsules
[0090] Hydrogel microcapsules are prepared using a polymerizable
material such as a monofunctional or multifunctional acrylic or
methacrylic acid, or ester thereof. See e.g., WO2014/011860.
Exemplary materials useful for preparing hydrogel microcapsules are
listed below.
[0091] 1.4.1 Monomers
[0092] Preferred bi- or polyfunctional vinyl monomers include by
way of illustration and not limitation, acrylic acid, methacrylic
acid, 2-hydroxyethyl acrylate, methyl acrylate, ethyl acrylate,
propyl acrylate, n-butyl acrylate, pentyl acrylate, hexyl acrylate,
2-ethylhexyl acrylate, heptyl acrylate, octyl acrylate, nonyl
acrylate, decyl acrylate, dodecyl acrylate, tetradecyl acrylate,
hexadecyl acrylate, isopropyl acrylate, isobutyl acrylate,
sec-butyl acrylate, 2-ethylbutyl acrylate, 3-methylbutyl acrylate,
1-ethylpropyl acrylate, 2-methylpentyl acrylate, 2-ethylbutyl
acrylate, 1,3-dimethylbutyl acrylate, 1-methylhexyl acrylate,
2-ethylhexyl acrylate, 1-methylheptyl acrylate,
4-ethyl-1-methyloctyl acrylate, 4-ethyl-1,1-isobutyloctyl acrylate,
allyl acrylate, 2-methylallyl acrylate, 1-methylallylacrylate,
2-butenyl acrylate, 1,3-dimethyl-3-dibutenyl acrylate,
3,7-dimethyl-7-octenyl acrylate, 3,7-dimethyl-2,6-octadienyl
acrylate, 3,7-dimethyl-6-octenyl acrylate, tert-butyl acrylate,
triethylene glycol diacrylate, triethylene glycol dimethacrylate,
diethylene glycol diacrylate, diethylene glycol dimethacrylate,
tripropylene glycol diacrylate, aliphatic or aromatic urethane
diacrylates, difunctional urethane acrylates, ethoxylated bisphenol
diacrylate, ethoxylated bisphenol dimethylacrylate, ethoxylated
aliphatic difunctional urethane methacrylates, ethoxylated
trimethylolpropane triacrylate, ethoxylated pentaerythritol
tetraacrylate, dipropylene glycol diacrylate, aliphatic or aromatic
urethane dimethacrylates, epoxy acrylates, epoxymethacrylates,
tetraethylene glycol dimethacrylate, tetraethylene glycol
diacrylate, polyethylene glycol dimethacrylate, polyethylene glycol
diacrylate, 1,3-butylene glycol diacrylate, 1,3-butylene glycol
dimethacrylate, 1,4-butanediol dimethacrylate, 1,4-butaneidiol
diacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol
dimethacrylate, neopentyl glycol diacrylate, alkoxylated hexanediol
diacrylate, alkoxylated cyclohexane dimethanol diacrylate,
propoxylated neopentyl glycol diacrylate, trimethylolpropane
trimethacrylate, trimethylolpropane triacrylate, pentaerythritol
triacrylate, propoxylated trimethylolpropane triacrylate,
propoxylated glyceryl triacrylate, ditrimethyloipropane
tetraacrylate, dipentaerythritol pentaacrylate, and the like.
Representative ester monomers of methacrylic acid, which can be
used include 2-hydrox ethyl methacrylate, glycidyl methacrylate,
methyl methacrylate, ethyl methacrylate, n-propyl methacrylate,
isopropyl methacrylate, n-butyl methacrylate, isobutyl
methacrylate, sec-butyl methacrylate, tert-butyl methacrylate,
n-hexyl methacrylate, n-octyl methacrylate, isooctyl methacrylate,
decyl methacrylate, n-dodecyl methacrylate, n-tetradecyl
methacrylate, n-hexadecyl methacrylate, 2-ethylhexyl methacrylate,
allyl methacrylate, oleyl methacrylate, 2-propynyl methacrylate,
2-(dimethylamino)ethyl methacrylate, 2-(diethylamino)ethyl
methacrylate, 2-(diisopropylamino)ethyl methacrylate,
N-(2-aminoethyl) methacrylamide hydrochloride, 2-aminoethyl
methacrylate hydrochloride, N-(3-aminopropyl)methacrylamide
hydrochloride, 2-(tert-butylamino)ethyl methacrylate, and the
like.
[0093] The above monomers may be employed separately or in various
mixtures. The use of multifunctional acrylate and methacrylate will
lead to the formation of cross-linked network polymers upon
polymerization. Such polymers have desirable properties such as
good mechanical strength, elasticity, toughness, and flexibility.
Examples of multifunctional acrylates and methacrylates of use in
this invention include, but are not limited to, ethylene glycol
dimethacrylate (EGDMA), trimethylolpropane trimethacrylate,
trimethyloyl triacrylate, pentaerythritol triacrylate,
pentaerythritol tetracrylate, bisphenol A dimethacrylate, di
(trimethylolpropane) tetraacrylate (DTTA),
1-(acryloyloxy)-3-(methacryloyloxy)-2-propanol (AOOP),
trimethylolpropane ethoxylate triacrylate (TPETA),
dipentaerythritol pentaacrylate, hexane diacrylate, poly (ethylene
glycol) dimethacrylate (PEGDMA), and 1,6-hexandiol dimethacrylate
(HDDMA), 1,4-butandiol dimethacrylate, 1,3-butandiol
dimethacrylate, 1,6-hexandiol diacrylate, 1,4-butandiol diacrylate,
1,3-butandiol diacrylate.
[0094] In certain embodiments, the acrylic or methacrylic acid, or
ester thereof, makes up less than 25% by mass, preferably 5 to 20%
by mass, or more preferably 10 to 15% by mass of the oil phase.
[0095] 1.4.2 Initiators
[0096] Initiators are often used to start the polymerization
reactions. Examples include but not limited to: AIBN, sodium
persulfate, benzoyl peroxide, and ammonium persulfate.
1.5 Coacervate Capsules
[0097] Proteins useful in coacervation processes include albumins,
vegetable globulins and gelatines. The gelatine may be fish, pork,
beef, and/or poultry gelatine, for example. According to a
preferred embodiment, the protein is fish, beef or poultry
gelatine. According to a more preferred embodiment, the protein is
warm water fish gelatine.
[0098] Typical non-protein polymers useful in complex coacervation
methods include, in particular, negatively charged polymers. For
example, they may be selected from gum arabic, xanthan, agar,
alginate salts, cellulose derivatives, for example carboxymethyl
cellulose, pectinate salts, carrageenan, polyacrylic and
methacrylic acid, and/or mixtures thereof. Further suitable
non-proteins can be derived from the literature, for example from
to WO 2004/022221.
[0099] A cross-linking agent is typically used to harden the
coating layer. Suitable cross-linking agents include formaldehyde,
acetaldehyde, glutaraldehyde, glyoxal, chrome alum, or
transglutaminase. Preferably, transglutaminase is used at 10-100,
preferably 30-60 activity units per gram of gelatine. This enzyme
is well described and commercially obtainable.
1.6 Microcapsule Formation Aids
[0100] Most microcapsule formation aids are used as dispersants
(namely, emulsifiers or surfactants). They facilitate the formation
of stable emulsions containing nano- or micro-sized oil drops to be
encapsulated. Further, microcapsule formation aids improve the
performance of the microcapsule by stabilizing capsules and/or
their deposition to the target areas or releasing to the
environment. Performance is measured by the intensity of the
fragrance release during the use experience, such as the pre-rub
and post-rub phases in a laundry experience. The pre-rub phase is
the phase when the microcapsules have been deposited on the cloth,
e.g., after a fabric softener containing microcapsules has been
used during the wash cycle. The post-rub phase is after the
microcapsules have been deposited and the microcapsules are broken
by friction or other similar mechanisms.
[0101] The amount of these microcapsule formation aids is anywhere
from about 0.1 to about 40 percent by weight of the microcapsule,
more preferably from 0.1 to about 10 percent, more preferably 0.1
to 5 percent by weight.
[0102] Preferred microcapsule formation aids are polyvinyl
pyrrolidone, polyvinyl alcohol, poly(styrene sulfonate),
carboxymethyl cellulose, sodium salt of naphthalene sulfonate
condensate, co-polymer of ethylene and maleic anhydride, an
alginate, hyaluronic acid, poly(acrylic acid),
carboxymethylcellulose, copolymers of acrylic acid and acrylamide,
copolymer of acrylamide and acrylamidopropyltrimonium chloride,
terpolymers of (acrylic acid, acrylamide, and
acrylamidopropyltrimonium chloride), partially or completely
hydrolyzed polyvinyl acetate polymers (i.e., polyvinyl alcohol),
and combinations thereof.
[0103] Other microcapsule formation aids include water-soluble
salts of alkyl sulfates, alkyl ether sulfates, alkyl isothionates,
alkyl carboxylates, alkyl sulfosuccinates, alkyl succinamates,
alkyl sulfate salts such as sodium dodecyl sulfate, alkyl
sarcosinates, alkyl derivatives of protein hydrolyzates, acyl
aspartates, alkyl or alkyl ether or alkylaryl ether phosphate
esters, sodium dodecyl sulphate, phospholipids or lecithin, or
soaps, sodium, potassium or ammonium stearate, oleate or palmitate,
alkylarylsulfonic acid salts such as sodium
dodecylbenzenesulfonate, sodium dialkylsulfosuccinates, dioctyl
sulfosuccinate, sodium dilaurylsulfosuccinate, poly(styrene
sulfonate) sodium salt, isobutylene-maleic anhydride copolymer, gum
arabic, sodium alginate, cellulose sulfate and pectin,
isobutylene-maleic anhydride copolymer, gum arabic, carrageenan,
sodium alginate, pectic acid, tragacanth gum, almond gum and agar;
semi-synthetic polymers such as sulfated cellulose, sulfated
methylcellulose, carboxymethyl starch, phosphated starch, lignin
sulfonic acid; and synthetic polymers such as maleic anhydride
copolymers (including hydrolyzates thereof), polyacrylic acid,
polymethacrylic acid, acrylic acid butyl acrylate copolymer or
crotonic acid homopolymers and copolymers, vinylbenzenesulfonic
acid or 2-acrylamido-2-methylpropanesulfonic acid homopolymers and
copolymers, and partial amide or partial ester of such polymers and
copolymers, carboxymodified polyvinyl alcohol, sulfonic
acid-modified polyvinyl alcohol and phosphoric acid-modified
polyvinyl alcohol, phosphated or sulfated tristyrylphenol
ethoxylates.
[0104] Commercially available surfactants include, but are not
limited to, sulfonated naphthalene-formaldehyde condensates such as
MORWET D425 (sodium salt of alkylnaphthalenesulfonate formaldehyde
condensate, Akzo Nobel, Fort Worth, Tex.); partially hydrolyzed
polyvinyl alcohols such as MOWIOLs, e.g., MOWIOL 3-83 (Air
Products), Ultalux FP, Ultalux FA, Ultalux AD, Selvol 203
(Sekisui), OKS-8089 (Sourus); ethylene oxide-propylene oxide block
copolymers or poloxamers such as PLURONIC, SYNPERONIC or PLURACARE
materials (BASF); sulfonated polystyrenes such as FLEXAN II (Akzo
Nobel); ethylene-maleic anhydride polymers such as ZEMAC (Vertellus
Specialties Inc.); copolymer of acrylamide and
acrylamidopropyltrimonium chloride such as Salcare SC 60 (BASF);
and Polyquaternium series such as Polyquaternium 11 ("PQ11;" a
copolymer of vinyl pyrrolidone and quaternized dimethylaminoethyl
methacrylate; sold by BASF as LUVIQUAT PQ11 AT 1). Surfactant
MOWIOL 3-83 has a viscosity of 2-4 mPaS (e.g., 3 mPaS), a degree of
hydrolysis of 80-85% (e.g., 83%), an ester value of 170-210 mg
KOH/g (e.g., 190 mg KOH/g), and a residual unhydrolyzed acetyl
content of 13-18% (e.g., 15%).
[0105] In other embodiments, the capsule formation aid is a
processing aid such as hydrocolloids, which improve the colloidal
stability of the slurry against coagulation, sedimentation and
creaming. The term "hydrocolloid" refers to a broad class of
water-soluble or water-dispersible polymers having anionic,
cationic, zwitterionic or non-ionic character. Hydrocolloids useful
in the present invention include, but are not limited to,
polycarbohydrates, such as starch, modified starch, dextrin,
maltodextrin, and cellulose derivatives, and their quaternized
forms; natural gums such as alginate esters, carrageenan,
xanthanes, agar-agar, pectines, pectic acid, and natural gums such
as gum arabic, gum tragacanth and gum karaya, guar gums and
quaternized guar gums; gelatine, protein hydrolysates and their
quaternized forms; synthetic polymers and copolymers, such as
poly(vinyl pyrrolidone-co-vinyl acetate), poly(vinyl
alcohol-co-vinyl acetate), poly((met)acrylic acid), poly(maleic
acid), poly(alkyl(meth)acrylate-co-(meth)acrylic acid),
poly(acrylic acid-co-maleic acid)copolymer, poly(alkyleneoxide),
poly(vinylmethylether), poly(vinylether-co-maleic anhydride), and
the like, as well as poly-(ethyleneimine), poly((meth)acrylamide),
poly(alkyleneoxide-co-dimethylsiloxane), poly(amino
dimethylsiloxane), Ultrez 20 (Acrylates/C10-30 Alkyl Acrylate
Crosspolymer), Carbopol.RTM. Ultrez 30 (cross-linked homopolymer of
acrylic acid polymerized in a cyclohexane and ethyl acetate
co-solvent system), Aculyn Excel (Acrylates Copolymer), Carbopol
981(Carbomer), and the like, and their quaternized forms.
[0106] The capsule formation aid may also be used in combination
with carboxymethyl cellulose ("CMC"), polyvinylpyrrolidone,
polyvinyl alcohol, alkylnaphthalenesulfonate formaldehyde
condensates, and/or a surfactant during processing to facilitate
capsule formation. Examples of surfactants that can be used in
combination with the capsule formation aid include, but are not
limited to, cetyl trimethyl ammonium chloride (CTAC), poloxamers
such as PLURONICS (e.g., PLURONIC F127), PLURAFAC (e.g., PLURAFAC
F127), or MIRANET-N, saponins such as QNATURALE (National Starch
Food Innovation); or a gum Arabic such as Seyal or Senegal. In
certain embodiments, the CMC polymer has a molecular weight range
between about 90,000 Daltons to 1,500,000 Daltons, preferably
between about 250,000 Daltons to 750,000 Daltons and more
preferably between 400,000 Daltons to 750,000 Daltons. The CMC
polymer has a degree of substitution between about 0.1 to about 3,
preferably between about 0.65 to about 1.4, and more preferably
between about 0.8 to about 1.0. The CMC polymer is present in the
capsule slurry at a level from about 0.1% to about 2% and
preferably from about 0.3% to about 0.7%. in other embodiments,
polyvinylpyrrolidone used in this invention is a water-soluble
polymer and has a molecular weight of 1,000 to 10,000,000. Suitable
polyvinylpyrrolidone are polyvinylpyrrolidone K12, K15, K17, K25,
K30, K60, K90, or a mixture thereof. The amount of
polyvinylpyrrolidone is 2-50%, 5-30%, or 10-25% by weight of the
capsule delivery system. Commercially available
alkylnaphthalenesulfonate formaldehyde condensates include MORWET
D-425, which is a sodium salt of naphthalene sulfonate condensate
by Akzo Nobel, Fort Worth, Tex.
[0107] In food products, food-grade dispersants are use. The term
"food-grade dispersant" refers to a dispersant having a quality as
fit for human consumption in food. They can be natural or
non-natural products. A natural product or surfactant refers to a
product that is naturally occurring and comes from a nature source.
Natural products/surfactants include their derivatives which can be
salted, desalted, deoiled, fractionated, or modified using a
natural enzyme or microorganism. On the other hand, a non-natural
surfactant is a chemically synthesized surfactant by a chemical
process that does not involve an enzymatic modification.
[0108] Natural dispersants include quillaja saponin, lecithins, gum
arabic, pectin, carrageenan, chitosan, chondroitin sulfate,
cellulose gum, modified starch, whey protein, pea protein, egg
white protein, silk protein, gelatin of fish, proteins of porcine
or bovine origin, ester gum, fatty acids, and combinations
thereof.
[0109] Non-natural dispersants include N-lauroyl-L-arginine ethyl
ester, sorbitan esters, polyethoxylated sorbitan esters,
polyglyceryl esters, fatty acid esters, and combination
thereof.
[0110] Other food safe dispersant can also be included in the
microcapsule of this invention. Examples include ammonium
phosphatides, acetic acid esters of mono- and diglycerides
(Acetem), lactic acid esters of mono- and diglycerides of fatty
acids (Lactem), citric acid esters of mono and diglycerides of
fatty acids (Citrem), mono and diacetyl tartaric acid esters of
mono and diglycerides of fatty acids (Datem), succinic acid esters
of monoglycerides of fatty acids (SMG), ethoxylated monoglycerides,
sucrose esters of fatty acids, sucroglycerides, polyglycerol
polyricinoleate, propane-1,2-diol esters of fatty acids, thermally
oxidized soya bean oil interacted with mono- or diglycerides of
fatty acids, sodium stearoyl lactylate (SSL), calcium stearoyl
lactylate (CSL), stearyl tartrate, polyglycerol esters of
interesterified castor oil acid (E476), sodium stearoyllatylate,
sodium lauryl sulfate, polyoxyethylated hydrogenated castor oil
(for instance, such sold under the trade name CREMO-PHOR), block
copolymers of ethylene oxide and propylene oxide (for instance as
sold under the trade name PLURONIC or the trade name POLOXAMER),
polyoxyethylene fatty alcohol ethers, and polyoxyethylene stearic
acid ester.
1.7 Additional Wall Polymer
[0111] The Encapsulating polymer can also include one or more
additional wall polymers, e.g., a second, third, fourth, fifth, or
sixth polymer. The additional polymers can be selected from the
group consisting of silica, polyacrylate, polyacrylamide,
poly(acrylate-co-acrylamide), polyurea, polyurethane, starch,
gelatin and gum Arabic, poly(melamine-formaldehyde),
poly(urea-formaldehyde), and combinations thereof.
1.8 Encapsulation Methods
[0112] Conventional encapsulation methods can be used to prepare
the reloadable microcapsules. See WO 2015/023961.
[0113] By way of illustration, to prepare a reloadable microcapsule
having a polyurea encapsulating polymer, an oil-in-water emulsion
is first prepared containing (i) a polyamine, a polyalcohol, or
mixture thereof, (ii) a polyisocyanate, carbonyl crosslinker, or
mixture thereof, (iii) an oil phase having a hydrophilic core
solvent and a hydrophobic core solvent, and (iv) an aqueous phase
having a microcapsule formation aid and water. The reaction between
the polyamine/polyalcohol and the polyisocyanate/carbonyl
crosslinker occurs when the temperature of the reaction mixture is
raised or a catalyst (such as a transglutaminase for catalyzing
amide formation) is added to the mixture.
[0114] Catalysts suitable for use in the polyurea/polyurethane
formation are transglutaminases, metal carbonates, metal hydroxide,
amino or organometallic compounds and include, for example, sodium
carbonate, cesium carbonate, potassium carbonate, lithium
hydroxide, 1,4-diazabicyclo[2.2.2]octane (i.e., DABCO),
N,N-dimethylaminoethanol, N,N-dimethylcyclohexylamine,
bis-(2-dimethylamino-ethyl) ether, N,N dimethylacetylamine,
stannous octoate and dibutyltin dilaurate.
[0115] The resultant microcapsule slurry is then cured at a
predetermined temperature for a predetermined period of time.
[0116] In accordance with some embodiments, the microcapsules
prepared according to the methods above are cured at a temperature
in the range of, e.g., 15.degree. C. to 230.degree. C. (e.g.,
55.degree. C. to 90.degree. C., 55.degree. C. to 75.degree. C., and
90.degree. C. to 130.degree. C.) for 1 minute to 10 hours (e.g.,
0.1 hours to 5 hours, 0.2 hours to 4 hours and 0.5 hours to 3
hours). A skilled person in the art can determine, without undue
experiments, the curing temperature, duration, and the heating
rate.
[0117] To obtain microcapsules with more leaching of the active
material, certain embodiments of this invention provide for a cure
at a low temperature, e.g., less than 100.degree. C. In some
embodiments, the cure temperature is at or less than 90.degree. C.
In other embodiments, the cure temperature is at or less than
80.degree. C.
[0118] In one embodiment, the capsules are heated to a target cure
temperature at a linear rate of 0.5 to 2.degree. C. per minute
(e.g., 1 to 5.degree. C. per minute, 2 to 8.degree. C. per minute,
and 2 to 10.degree. C. per minute) over a period of 1 to 60 minutes
(e.g., 1 to 30 minutes). The following heating methods may be used:
conduction for example via oil, steam radiation via infrared, and
microwave, convection via heated air, steam injection and other
methods known by those skilled in the art. The target cure
temperature used herein refers to the minimum temperature in
degrees Celsius at which the capsules may be cured to retard
leaching.
2. Active Materials
[0119] The microcapsule compositions of the invention have one or
more active materials in the external hydrophilic solvent.
Nonlimiting examples include those described in WO 2016/049456.
These active material include a fragrance, pro-fragrance, flavor,
malodor counteractive agent, vitamin or derivative thereof,
anti-inflammatory agent, fungicide, anesthetic, analgesic,
antimicrobial active, anti-viral agent, anti-infectious agent,
anti-acne agent, skin lightening agent, insect repellent, animal
repellent, vermin repellent, emollient, skin moisturizing agent,
wrinkle control agent, UV protection agent, fabric softener active,
hard surface cleaning active, skin or hair conditioning agent,
flame retardant, antistatic agent, taste modulator, cell,
probiotic, antioxidant, self-tanning agent, dihydroxyacetone,
cooler, sensate, malodor reactive material, cosmetic active, and
combinations thereof. Cosmetic actives include vitamins, sun
filters and sunscreens, anti-aging agents, anti-wrinkle agents,
antioxidants, lifting agents, firming agents, anti-spot agents,
anti-redness agents, thinning agents, draining agents,
moisturizers, soothing agents, scrubbing or exfoliating agents,
mattifying agents, sebum regulating agents, skin-lightening
actives, self-tanning actives, tanning accelerators and
combinations thereof. In addition to the active materials listed
above, the products of this invention can also contain dyes,
colorants or pigments, naturally obtained extracts (for example
paprika extract and black carrot extract), and aluminum lakes. The
microcapsule compositions of the invention are particularly
suitable for encapsulating fragrances containing one or more
aldehydes, amines, and/or alcohols. Aldehydes/amines/alcohols can
react with microcapsule wall forming materials such as
polyisocyanates, silicate, acrylates, etc.
[0120] In some embodiments, the amount of active material in the
microcapsule composition is from 0.1 to 95% (e.g., 0.5 to 10%, 1 to
90%, 2% to 80%, 4 to 70%, and 5 to 50%) by weight of the
composition. The amount of the capsule wall is from 1 to 98% (e.g.,
1 to 50%, 2 to 20%, and 3 to 15%) by weight of the capsule. The
amount of the microcapsule core (the sum of the hydrophilic and
hydrophobic core solvents) is from 10 to 99% (e.g., 20 to 95%, 50
to 95%, and 80 to 95%) by weight of the capsule.
[0121] In some microcapsule compositions, the ratio between the
capsule and active material is 1:2 to 40:1 (e.g., 1:1 to 30:1 and
1:1 to 20:1).
3. Adjunct Materials
[0122] In addition to the active materials, the present invention
also contemplates the incorporation of adjunct materials including
solvent, emollients, and core modifier materials in the core
encapsulated by the capsule wall. Other adjunct materials are
nanoscale solid particulate materials, polymeric core modifiers,
solubility modifiers, density modifiers, stabilizers, humectants,
viscosity modifiers, pH modifiers, or any combination thereof.
These modifiers can be present in the wall or core of the capsules,
or outside the capsules in delivery system. Preferably, they are in
the core as a core modifier.
[0123] The one or more adjunct material may be added in the amount
of from 0.01% to 25% (e.g., from 0.5% to 10%) by weight of the
capsule.
[0124] Suitable examples include those described in WO 2016/049456
and US 2016/0158121.
4. Deposition Aids
[0125] A capsule deposition aid from 0.01 to 25%, more preferably
from 5 to 20% can be included by weight of the capsule. The capsule
deposition aid can be added during the preparation of the capsules
or it can be added after the capsules have been made.
[0126] These deposition aids are used to aid in deposition of
capsules to surfaces such as fabric, hair or skin. These include
anionically, cationically, nonionically, or amphoteric
water-soluble polymers. Suitable deposition aids include
polyquaternium-4, polyquaternium-5, polyquaternium-6,
polyquaternium-7, polyquaternium-10, polyquaternium-16,
polyquaternium-22, polyquaternium-24, polyquaternium-28,
polyquaternium-39, polyquaternium-44, polyquaternium-46,
polyquaternium-47, polyquaternium-53, polyquaternium-55,
polyquaternium-67, polyquaternium-68, polyquaternium-69,
polyquaternium-73, polyquaternium-74, polyquaternium-77,
polyquaternium-78, polyquaternium-79, polyquaternium-80,
polyquaternium-81, polyquaternium-82, polyquaternium-86,
polyquaternium-88, polyquaternium-101, polyvinylamine,
polyethyleneimine, polyvinylamine and vinylformamide copolymer, an
acrylamidopropyltrimonium chloride/acrylamide copolymer, a
methacrylamidopropyltrimonium chloride/acrylamide copolymer,
polymer comprising units derived from polyethylene glycol and
terephthalate, polyester, polymer derivable from dicarboxylic acids
and polyols, and combinations thereof. the polyester substantive
deposition aid is a phthalate containing polymer, more preferably a
polymer comprising units derived from (poly)ethylene glycol and
terephthalate, most preferably selected from the group comprising
PET/POET, PEG/POET, PET/PEG and phthalate/glycerol/ethylene glycol
polymers as described in WO 2009037060. Other suitable deposition
aids include those described in WO 2016049456, pages 13-27.
Additional deposition aids are described in US 2013/0330292, US
2013/0337023, and US 2014/0017278.
5. Microcapsule Delivery System Formulations
[0127] The reloadable microcapsule can be formulated into a capsule
delivery system (e.g., a microcapsule composition) for use in
consumer products.
[0128] The capsule delivery system can be a slurry containing in an
external hydrophilic solvent (e.g., water, ethanol, and a
combination thereof) the capsule at a level 0.1 to 80% (e.g.,
70-75%, 40-55%, 50-90%, 1 to 65%, and 5 to 45%) by weight of the
capsule delivery system.
[0129] In some embodiments, the capsule and its slurry prepared in
accordance with the present invention is subsequently purified. See
US 2014/0017287. Purification can be achieved by washing the
capsule slurry with water until a neutral pH is achieved.
6. Additional Components
[0130] The capsule delivery system can also contain one or more
other delivery system such as polymer-assisted delivery
compositions (see U.S. Pat. No. 8,187,580), fiber-assisted delivery
compositions (US 2010/0305021), cyclodextrin host guest complexes
(U.S. Pat. No. 6,287,603 and US 2002/0019369), pro-fragrances (WO
2000/072816 and EP 0 922 084), and any combination thereof. The
capsule delivery system can also contain one or more (e.g., two,
three, four, five or six more) different capsules including
different capsules of this invention and other capsules such as
such as aminoplasts, hydrogel, sol-gel, polyurea/polyurethane
capsules, and melamine formaldehyde capsules. More exemplary
delivery systems that can be incorporated are coacervate capsules
(see WO 2004/022221) and cyclodextrin delivery systems (see WO
2013/109798 and US 2011/03085560).
[0131] Any compound, polymer, or agent discussed above can be the
compound, polymer, or agent itself as shown above, or its salt,
precursor, hydrate, or solvate. A salt can be formed between an
anion and a positively charged group on the compound, polymer, or
agent. Suitable anions include chloride, bromide, iodide, sulfate,
nitrate, phosphate, citrate, methanesulfonate, trifluoroacetate,
acetate, malate, tosylate, tartrate, fumurate, glutamate,
glucuronate, lactate, glutarate, and maleate. Likewise, a salt can
also be formed between a cation and a negatively charged group on
the compound, polymer, or agent. Suitable cations include sodium
ion, potassium ion, magnesium ion, calcium ion, and an ammonium
cation (e.g., tetramethylammonium ion). A precursor can be ester
and another suitable derivative, which, during the process of
preparing a polyurea or polyurethane capsule composition of this
invention, is capable of converting to the compound, polymer, or
agent and being used in preparing the polyurea or polyurethane
capsule composition. A hydrate refers to the compound, polymer, or
agent that contains water. A solvate refers to a complex formed
between the compound, polymer, or agent and a suitable solvent. A
suitable solvent can be water, ethanol, isopropanol, ethyl acetate,
acetic acid, and ethanolamine.
[0132] Certain compounds, polymers, and agents have one or more
stereocenters, each of which can be in the R or S configuration, or
a mixture. Further, some compounds, polymers, and agents possess
one or more double bonds wherein each double bond exists in the E
(trans) or Z (cis) configuration, or combinations thereof. The
compounds, polymers, and agents include all possible
configurational stereoisomeric, regioisomeric, diastereomeric,
enantiomeric, and epimeric forms as well as any mixtures thereof.
As such, lysine used herein includes L-lysine, D-lysine, L-lysine
monohydrochloride, D-lysine monohydrochloride, lysine carbonate,
and so on. Similarly, arginine includes L-arginine, D-arginine,
L-arginine monohydrochloride, D-arginine monohydrochloride,
arginine carbonate, arginine monohydrate, and etc. Guanidine
includes guanidine hydrochloride, guanidine carbonate, guanidine
thiocyanate, and other guanidine salts including their hydrates.
Ornithine include L-ornithine and its salts/hydrates (e.g.,
monohydrochloride) and D-ornithine and its salts/hydrates (e.g.,
monohydrochloride).
7. Applications
[0133] The delivery systems of the present invention are
well-suited for use, without limitation, in the following products:
[0134] a) Household products [0135] i. Liquid or Powder Laundry
Detergents which can use the present invention include those
systems described in U.S. Pat. Nos. 5,929,022, 5,916,862,
5,731,278, 5,565,145, 5,470,507, 5,466,802, 5,460,752, 5,458,810,
5,458,809, 5,288,431, 5,194,639, 4,968,451, 4,597,898, 4,561,998,
4,550,862, 4,537,707, 4,537,706, 4,515,705, 4,446,042, and
4,318,818 [0136] ii. Unit Dose Pouches, Tablets and Capsules such
as those described in EP 1 431 382 A1, US 2013/0219996 A1, US
2013/0284637 A1, and U.S. Pat. No. 6,492,315. These unit dose
formulations can contain high concentrations of a functional
material (e.g., 5-100% fabric softening agent or detergent active),
fragrance (e.g., 0.5-100%, 0.5-40%, and 0.5-15%), and flavor (e.g.,
0.1-100%, 0.1-40%, and 1-20%). They can contain no water to limit
the water content as low as less than 30% (e.g., less than 20%,
less than 10%, and less than 5%). [0137] iii. Scent Boosters such
as those described in U.S. Pat. No. 7,867,968, U.S. Pat. No.
7,871,976, U.S. Pat. No. 8,333,289, US 2007/0269651 A1, and
US2014/0107010 A1. [0138] iv. Fabric Care Products such as Rinse
Conditioners (containing 1 to 30 weight % of a fabric conditioning
active), Fabric Liquid Conditioners (containing 1 to 30 weight % of
a fabric conditioning active), Tumble Drier Sheets, Fabric
Refreshers, Fabric Refresher Sprays, Ironing Liquids, and Fabric
Softener Systems such as those described in U.S. Pat. Nos.
6,335,315, 5,674,832, 5,759,990, 5,877,145, 5,574,179, 5,562,849,
5,545,350, 5,545,340, 5,411,671, 5,403,499, 5,288,417, 4,767,547
and 4,424,134 [0139] Liquid fabric softeners/fresheners contains at
least one fabric softening agent present, preferably at a
concentration of 1 to 30% (e.g., 4 to 20%, 4 to 10%, and 8 to 15%).
The ratio between the active material and the fabric softening
agent can be 1:500 to 1:2 (e.g., 1:250 to 1:4 and 1:100 to 1:8). As
an illustration, when the fabric softening agent is 5% by weight of
the fabric softener, the active material is 0.01 to 2.5%,
preferably 0.02 to 1.25% and more preferably 0.1 to 0.63%. As
another example, when the fabric softening agent is 20% by weight
of the fabric softener, the active material is 0.04 to 10%,
preferably 0.08 to 5% and more preferably 0.4 to 2.5%. The active
material is a fragrance, malodor counteractant or mixture thereof.
The liquid fabric softener can have 0.15 to 15% of capsules (e.g.,
0.5 to 10%, 0.7 to 5%, and 1 to 3%). When including capsules at
these levels, the neat oil equivalent (NOE) in the softener is 0.05
to 5% (e.g., 0.15 to 3.2%, 0.25 to 2%, and 0.3 to 1%). [0140]
Suitable fabric softening agents include cationic surfactants.
Non-limiting examples are quaternary ammonium compounds such as
alkylated quaternary ammonium compounds, ring or cyclic quaternary
ammonium compounds, aromatic quaternary ammonium compounds,
diquaternary ammonium compounds, alkoxylated quaternary ammonium
compounds, amidoamine quaternary ammonium compounds, ester
quaternary ammonium compounds, and mixtures thereof. Fabric
softening compositions, and components thereof, are generally
described in US 2004/0204337 and US 2003/0060390. Suitable
softening agents include esterquats such as Rewoquat WE 18
commercially available from Evonik Industries and Stepantex SP-90
commercially available from Stepan Company. [0141] v. Liquid dish
detergents such as those described in U.S. Pat. Nos. 6,069,122 and
5,990,065 [0142] vi. Automatic Dish Detergents such as those
described in U.S. Pat. Nos. 6,020,294, 6,017,871, 5,968,881,
5,962,386, 5,939,373, 5,914,307, 5,902,781, 5,705,464, 5,703,034,
5,703,030, 5,679,630, 5,597,936, 5,581,005, 5,559,261, 4,515,705,
5,169,552, and 4,714,562 [0143] vii. All-purpose Cleaners including
bucket dilutable cleaners and toilet cleaners [0144] viii. Bathroom
Cleaners [0145] ix. Bath Tissue [0146] x. Rug Deodorizers [0147]
xi. Candles [0148] xii. Room Deodorizers [0149] xiii. Floor
Cleaners [0150] xiv. Disinfectants [0151] xv. Window Cleaners
[0152] xvi. Garbage bags/trash can liners [0153] xvii. Air
Fresheners including room deodorizer and car deodorizer, scented
candles, sprays, scented oil air freshener, Automatic spray air
freshener, and neutralizing gel beads [0154] xviii. Moisture
absorber [0155] xix. Household Devices such as paper towels and
disposable Wipes [0156] xx. Moth balls/traps/cakes [0157] b) Baby
Care Products [0158] i. Diaper Rash Cream/Balm [0159] ii. Baby
Powder [0160] c) Baby Care Devices [0161] i. Diapers [0162] ii.
Bibs [0163] iii. Wipes [0164] d) Oral Care Products. Tooth care
products (as an example of preparations according to the invention
used for oral care) generally include an abrasive system (abrasive
or polishing agent), for example silicic acids, calcium carbonates,
calcium phosphates, aluminum oxides and/or hydroxylapatites,
surface-active substances, for example sodium lauryl sulfate,
sodium lauryl sarcosinate and/or cocamidopropylbetaine, humectants,
for example glycerol and/or sorbitol, thickening agents, for
example carboxymethyl cellulose, polyethylene glycols, carrageenan
and/or Laponite.RTM., sweeteners, for example saccharin, taste
correctors for unpleasant taste sensations, taste correctors for
further, normally not unpleasant taste sensations, taste-modulating
substances (for example inositol phosphate, nucleotides such as
guanosine monophosphate, adenosine monophosphate or other
substances such as sodium glutamate or 2-phenoxypropionic acid),
cooling active ingredients, for example menthol derivatives, (for
example L-menthyllactate, L-menthylalkylcarbonates, menthone
ketals, menthane carboxylic acid amides), 2,2,2-trialkylacetic acid
amides (for example 2,2-diisopropylpropionic acid methyl amide),
icilin and icilin derivatives, stabilizers and active ingredients,
for example sodium fluoride, sodium monofluorophosphate, tin
difluoride, quaternary ammonium fluorides, zinc citrate, zinc
sulfate, tin pyrophosphate, tin dichloride, mixtures of various
pyrophosphates, triclosan, cetylpyridinium chloride, aluminum
lactate, potassium citrate, potassium nitrate, potassium chloride,
strontium chloride, hydrogen peroxide, flavorings and/or sodium
bicarbonate or taste correctors. [0165] i. Tooth Paste. An
exemplary formulation as follows: [0166] 1. calcium phosphate
40-55% [0167] 2. carboxymethyl cellulose 0.8-1.2% [0168] 3. sodium
lauryl sulfate 1.5-2.5% [0169] 4. glycerol 20-30% [0170] 5.
saccharin 0.1-0.3% [0171] 6. flavor oil 1-2.5% [0172] 7. water q.s.
to 100% [0173] A typical procedure for preparing the formulation
includes the steps of (i) mixing by a blender according to the
foregoing formulation to provide a toothpaste, and (ii) adding a
composition of this invention and blending the resultant mixture
till homogeneous. [0174] ii. Tooth Powder [0175] iii. Oral Rinse
[0176] iv. Tooth Whiteners [0177] v. Denture Adhesive [0178] e)
Health Care Devices [0179] i. Dental Floss [0180] ii. Toothbrushes
[0181] iii. Respirators [0182] iv. Scented/flavored condoms [0183]
f) Feminine Hygiene Products such as Tampons, Feminine Napkins and
Wipes, and Pantiliners [0184] g) Personal Care Products: Cosmetic
or pharmaceutical preparations, e.g., a "water-in-oil" (W/O) type
emulsion, an "oil-in-water" (O/W) type emulsion or as multiple
emulsions, for example of the water-in-oil-in-water (W/O/W) type,
as a PIT emulsion, a Pickering emulsion, a micro-emulsion or
nano-emulsion; and emulsions which are particularly preferred are
of the "oil-in-water" (O/W) type or water-in-oil-in-water (W/O/W)
type. More specifically, [0185] i. Personal Cleansers (bar soaps,
body washes, and shower gels) [0186] ii. In-shower conditioner
[0187] iii. Sunscreen ant tattoo color protection (sprays, lotions,
and sticks) [0188] iv. Insect repellents [0189] v. Hand Sanitizer
[0190] vi. Antiinflammatory balms, ointments, and sprays [0191]
vii. Antibacterial ointments and creams [0192] viii. Sensates
[0193] ix. Deodorants and Antiperspirants including aerosol and
pump spray antiperspirant, stick antiperspirant, roll-on
antiperspirant, emulsion spray antiperspirant, clear emulsion stick
antiperspirant, soft solid antiperspirant, emulsion roll-on
antiperspirant, clear emulsion stick antiperspirant, opaque
emulsion stick antiperspirant, clear gel antiperspirant, clear
stick deodorant, gel deodorant, spray deodorant, roll-on, and cream
deordorant. [0194] x. Wax-based Deodorant. An exemplary formulation
as follows: [0195] 1. Parafin Wax 10-20% [0196] 2. Hydrocarbon Wax
5-10% [0197] 3. White Petrolatum 10-15% [0198] 4. Acetylated
Lanolin Alcohol 2-4% [0199] 5. Diisopropyl Adipate 4-8% [0200] 6.
Mineral Oil 40-60% [0201] 7. Preservative (as needed) [0202] The
formulation is prepared by (i) mixing the above ingredients, (ii)
heating the resultant composition to 75.degree. C. until melted,
(iii) with stirring, adding 4% cryogenically ground polymer
containing a fragrance while maintaining the temperature 75.degree.
C., and (iv) stirring the resulting mixture in order to ensure a
uniform suspension while a composition of this invention is added
to the formulation. [0203] xi. Glycol/Soap Type Deodorant. An
exemplary formulation as follows: [0204] 1. Propylene Glycol 60-70%
[0205] 2. Sodium Stearate 5-10% [0206] 3. Distilled Water 20-30%
[0207] 4.2,4,4-Trichloro-2'-Hydroxy Diphenyl Ether, manufactured by
the Ciba-Geigy Chemical Company and a Trademark of the Ciba-Geigy
Chemical Company) 0.01-0.5% [0208] The ingredients are combined and
heated to 75.degree. C. with stirring until the sodium stearate has
dissolved. The resulting mixture is cooled to 40.degree. C.
followed by addition of a composition of this invention. [0209]
xii. Lotion including body lotion, facial lotion, and hand lotion
[0210] xiii. Body powder and foot powder [0211] xiv. Toiletries
[0212] xv. Body Spray, aerosol or non-aerosol body spray
(WO2014/014705 and WO2016205023) [0213] xvi. Shave cream and male
grooming products [0214] xvii. Bath Soak [0215] xviii. Exfoliating
Scrub [0216] h) Personal Care Devices [0217] i. Facial Tissues
[0218] ii. Cleansing wipes [0219] i) Hair Care Products [0220] i.
Shampoos (liquid and dry powder) [0221] ii. Hair Conditioners
(Rinse-out conditioners, leave-in conditioners, and cleansing
conditioners) [0222] iii. Hair Rinses [0223] iv. Hair Refreshers
[0224] v. Hair perfumes [0225] vi. Hair straightening products
[0226] vii. Hair styling products, Hair Fixative and styling aids
[0227] viii. Hair combing creams [0228] ix. Hair wax [0229] x. Hair
foam, hair gel, nonaerosol pump spray [0230] xi. Hair Bleaches,
Dyes and Colorants [0231] xii. Perming agents [0232] xiii. Hair
wipes [0233] j) Beauty Care [0234] i. Fine Fragrance--Alcoholic.
Compositions and methods for incorporating fragrance capsules into
alcoholic fine fragrances are described in U.S. Pat. No. 4,428,869.
Alcoholic fine fragrances may contain the following: [0235] 1.
Ethanol (1-99%) [0236] 2. Water (0-99%) [0237] 3. A suspending aide
including but not limited to: hydroxypropyl cellulose, ethyl
cellulose, silica, microcrystalline cellulose, carrageenan,
propylene glycol alginate, methyl cellulose, sodium carboxymethyl
cellulose or xanthan gum (0.1-1%) [0238] 4. Optionally an
emulsifier or an emollient may be included including but not
limited to those listed above [0239] ii. Solid Perfume [0240] iii.
Lipstick/lip balm [0241] iv. Make-up cleanser [0242] v. Skin care
cosmetic such as foundation, pack, sunscreen, skin lotion, milky
lotion, skin cream, emollients, skin whitening [0243] vi. Make-up
cosmetic including manicure, mascara, eyeliner, eye shadow, liquid
foundation, powder foundation, lipstick and cheek rouge [0244] k)
Consumer goods packaging such as fragranced cartons, fragranced
plastic bottles/boxes [0245] l) Pet care products [0246] i. Cat
litter [0247] ii. Flea and tick treatment products [0248] iii. Pet
grooming products [0249] iv. Pet shampoos [0250] v. Pet toys,
treats, and chewables [0251] vi. Pet training pads [0252] vii. Pet
carriers and crates [0253] m) Confectionaries confectionery,
preferably selected from the group consisting of chocolate,
chocolate bar products, other products in bar form, fruit gums,
hard and soft caramels and chewing gum [0254] i. Gum [0255] 1. Gum
base (natural latex chicle gum, most current chewing gum bases also
presently include elastomers, such as polyvinylacetate (PVA),
polyethylene, (low or medium molecular weight) polyisobutene (PIB),
polybutadiene, isobutene-isoprene copolymers (butyl rubber),
polyvinylethylether (PVE), polyvinylbutyether, copolymers of vinyl
esters and vinyl ethers, styrene-butadiene copolymers
(styrene-butadiene rubber, SBR), or vinyl elastomers, for example
based on vinylacetate/vinyllaurate, vinylacetate/vinylstearate or
ethylene/vinylacetate, as well as mixtures of the mentioned
elastomers, as described for example in EP 0 242 325, U.S. Pat. No.
4,518,615, U.S. Pat. No. 5,093,136, U.S. Pat. No. 5,266,336, U.S.
Pat. No. 5,601,858 or U.S. Pat. No. 6,986,709) 20-25% [0256] 2.
Powdered sugar 45-50% [0257] 3. glucose 15-17% [0258] 4. starch
syrup 10-13% [0259] 5. plasticizer 0.1% [0260] 6. flavor 0.8-1.2%
[0261] The components described above were kneaded by a kneader
according to the foregoing formulation to provide a chewing gum.
Encapsulated Flavor or sensate is then added and blended till
homogeneous. [0262] ii. Breath Fresheners [0263] iii. Orally
Dissolvable Strips [0264] iv. Chewable Candy [0265] v. Hard Candy
[0266] n) Baked products, preferably selected from the group
consisting of bread, dry biscuits, cakes and other cookies; [0267]
o) snack foods, preferably selected from the group consisting of
baked or fried potato chips or potato dough products, bread dough
products and corn or peanut-based extrudates; [0268] i. Potato,
tortilla, vegetable or multigrain chips [0269] ii. Popcorn [0270]
iii. Pretzels [0271] iv. Extruded stacks [0272] p) Cereal Products
preferably selected from the group consisting of breakfast cereals,
muesli bars and precooked finished rice products [0273] q)
Alcoholic and non-alcoholic beverages, preferably selected from the
group consisting of coffee, tea, wine, beverages containing wine,
beer, beverages containing beer, liqueurs, schnapps, brandies,
sodas containing fruit, isotonic beverages, soft drinks, nectars,
fruit and vegetable juices and fruit or vegetable preparations;
instant beverages, preferably selected from the group consisting of
instant cocoa beverages, instant tea beverages and instant coffee
beverages [0274] i. Ready to drink liquid drinks [0275] ii. Liquid
Drink Concentrates [0276] iii. Powder Drinks [0277] iv. Coffee:
Instant Cappucino [0278] 1. Sugar 30-40% [0279] 2. Milk Powder
24-35% [0280] 3. Soluble Coffee 20-25% [0281] 4. Lactose 1-15%
[0282] 5. Food Grade Emulsifier 1-3%
[0283] 6. Encapsulated Volatile Flavor 0.01-0.5% [0284] v. Tea
[0285] vi. Alcoholic [0286] r) Spice blends and consumer prepared
foods [0287] i. Powder gravy, sauce mixes [0288] ii. Condiments
[0289] iii. Fermented Products [0290] s) Ready to heat foods: ready
meals and soups, preferably selected from the group consisting of
powdered soups, instant soups, precooked soups [0291] i. Soups
[0292] ii. Sauces [0293] iii. Stews [0294] iv. Frozen entrees
[0295] t) Dairy Products milk products, preferably selected from
the group consisting of milk beverages, ice milk, yogurt, kefir,
cream cheese, soft cheese, hard cheese, powdered milk, whey,
butter, buttermilk and partially or fully hydrolyzed milk
protein-containing products Flavored milk beverages [0296] i.
Yoghurt [0297] ii. Ice cream [0298] iii. Bean Curd [0299] iv.
Cheese [0300] u) Soya protein or other soybean fractions,
preferably selected from the group consisting of soya milk and
products produced therefrom, soya lecithin-containing preparations,
fermented products such as tofu or tempeh or products produced
therefrom and soy sauces; [0301] v) Meat products, preferably
selected from the group consisting of ham, fresh or raw sausage
preparations, and seasoned or marinated fresh or salt meat products
[0302] w) Eggs or egg products, preferably selected from the group
consisting of dried egg, egg white and egg yolk [0303] x) Oil-based
products or emulsions thereof, preferably selected from the group
consisting of mayonnaise, remoulade, dressings and seasoning
preparations [0304] y) fruit preparations, preferably selected from
the group consisting of jams, sorbets, fruit sauces and fruit
fillings; vegetable preparations, preferably selected from the
group consisting of ketchup, sauces, dried vegetables, deep-frozen
vegetables, precooked vegetables, vegetables in vinegar and
preserved vegetables [0305] z) Flavored pet foods.
[0306] The above-listed applications are all well known in the art.
For example, fabric softener systems are described in U.S. Pat. No.
6,335,315. Liquid laundry detergents include those systems
described in U.S. Pat. No. 5,929,022. Liquid dish detergents are
described in U.S. Pat. No. 6,069,122. Shampoo and conditioners that
can employ the present invention include those described in U.S.
Pat. No. 6,162,423. Automatic Dish Detergents are described in U.S.
Pat. No. 6,020,294.
[0307] The terms "polyfunctional isocyanate," "multifunctional
isocyanate," and "polyisocyanate" all refer to a compound having
two or more isocyanate (--NCO) groups.
[0308] The terms "polyfunctional amine," "multifunctional amine,"
and "polyamine" refer to a compound having two or more primary or
secondary amine groups. These terms also refer to a compound
containing one or more primary/secondary amine groups and one or
more hydroxyl groups (--OH).
[0309] The terms "microcapsule" and "capsule" are used herein
interchangeably.
[0310] The terms "polyfunctional alcohol," "multifunctional
alcohol," "poly alcohol," and "polyol" refer to a compound having
two or more hydroxyl groups.
[0311] The invention is described in greater detail by the below
non-limiting examples. Without further elaboration, it is believed
that one skilled in the art can, based on the description herein,
utilize the present invention to its fullest extent. All
publications cited herein are incorporated by reference in their
entirety.
Example 1: Neobee Oil as the Hydrophobic Core Solvent
[0312] A reloadable microcapsule of this invention, i.e., Capsule
1, was prepared following the procedure described below.
[0313] More specifically, 120 g of NEOBEE oil (Stepan, Chicago,
Ill.; a mixture of caprylic/capric triglycerides) was weighed out
and combined with 9.6 g of isocyanate monomer, LUPRANATE M20 (BASF
corporation, Wyandotte, Mich.) to form an oil phase. In a separate
beaker, a 1% surfactant solution (160 g) was prepared by dissolving
1.6 g of MORWET D-425 (Akzo Nobel, Fort Worth, Tex.) in water. The
oil phase was then emulsified into the surfactant solution to form
an oil-in-water emulsion under shearing (ULTRA TURRAX, T25 Basic,
IKA WERKE) at 9500 rpm for two minutes.
[0314] The oil-in-water emulsion was placed in a round bottom
vessel and 10.8 g of 40% hexamethylene diamine (HMDA) aqueous
solution (INVISTA, Wichita, Kans.) was added under constant mixing
with an overhead mixer. The mixer speed was reduced after the
addition of HMDA was complete. The capsule slurry was cured at
55.degree. C. for three hours to obtain Capsule 1. This reloadable
microcapsule has (i) a microcapsule wall formed of polyurea and
(ii) a microcapsule core consisting of a hydrophobic core solvent
(Neobee oil).
[0315] The size of the capsule was measure to be in the range of
5-10 microns using a dynamic light scattering (DLS) instrument.
Example 2: Triethyl Citrate as a Hydrophilic Core Solvent
[0316] Capsule 2 of this invention was prepared following the same
procedure described in Example 1 except that 120 g of triethyl
citrate (Vertellus Performance Materials Inc. Greensboro, N.C.) was
used instead of Neobee oil.
[0317] Capsule 2 has (i) a microcapsule wall formed of polyurea and
(ii) a microcapsule core consisting of a hydrophilic core solvent
(triethyl citrate).
[0318] The size of the capsule was measure to be in the range of
5-10 microns using an DLS instrument.
Example 3: A Mixture of Neobee Oil and Triethyl Citrate in the
Core
[0319] Capsule 3 of this invention was prepared following the same
procedure described in Example 1 except that a mixture of 60 g of
triethyl citrate and 60 g of Neobee oil was used instead of Neobee
oil.
[0320] Capsule 3 has (i) a microcapsule wall formed of polyurea and
(ii) a microcapsule core consisting of a hydrophilic core solvent
(triethyl citrate) and a hydrophobic core solvent (Neobee oil).
[0321] The average particle size of the capsule was measure to be
in the range of 5-10 microns using an DLS instrument.
Performance of Reloadable Capsules Blended with Fragrance in
Aerosol Base
[0322] To establish the consumer benefit of Capsules 1-3, these
three reloadable microcapsules in the slurry as prepared each were
added, together with fragrance Apple (International Flavors and
Fragrance, Union Beach, N.J.), to an aerosol base to obtain three
microcapsule compositions, i.e., S1-S3 respectively. Each
microcapsule composition contains by weight 4% fragrance, 12.5%
capsule slurry and 83.5% aerosol. The composition of the aerosol is
provided in Table 1.
[0323] A control composition, i.e., Comparative Composition S1',
was prepared by mixing 4% fragrance Apple alone with the aerosol
base.
TABLE-US-00001 TABLE 1 Ingredient Description % A46
Propellant(Butane/Isobutane Mix) 52.4 Alcohol Diluent 42.8
Fragrance Perfume 4 Propylene Glycol Solubilizer 0.6 COSMOCIL CQ
Deodorant Active 0.2
[0324] Each of S1-S3 and S1' (1 g) was sprayed onto a baby T-shirt.
Eight T-shirts were evaluated per microcapsule composition by 15
trained judges. The judges rated the fragrance intensity 5 hours
after spraying the microcapsule composition and then rubbing
(post-rub) the T-shirt for 5 times. The fragrance intensity was
rated at a scale ranging from 0 to 10. A numerical value of 2
indicates that the composition produces a weak intensity. A value
of 10 indicates that the composition generates a very strong
smell.
[0325] The sensory results are given in Table 2. The analysis
indicated that reloadable capsule compositions (S1-S3) provided
significantly greater post-rub fragrance intensity as compared to
neat fragrance in Comparative Composition S1').
TABLE-US-00002 TABLE 2 Samples Post-rubbing fragrance intensity S1'
(Neat) 1.93 S1 3.79 S2 3.14 S3 5.07
Example 4: A Large Reloadable Capsules with a Mixture of Neobee Oil
and Triethyl Citrate (Particle Size: 30 Microns)
[0326] A fourth reloadable microcapsule, i.e., Capsule 4, was
prepared following the procedure below. NEOBEE oil (120 g) and
triethyl citrate (120 g) were combined with 4.8 g of isocyanate
monomer, LUPRANATE M20 to form an oil phase. In a separate beaker,
a 0.5% surfactant solution (319.2 g) was prepared by dissolving 1.6
g of Mowiol 3-85, a partially hydrolyzed polyvinyl alcohol
(Kuraray, Houston, Tex.) in water. The oil phase was then
emulsified into the surfactant solution to form an oil-in-water
emulsion under shearing (ULTRA TURRAX, T25 Basic, IKA WERKE) at
3000 rpm for three minutes.
[0327] To the oil-in-water emulsion was added 36 g of 6% HMDA
aqueous solution under agitation. The resultant capsule slurry was
cured at 55.degree. C. for three hours to obtain Capsule 4. The
average particle size of the capsule was measure to be 30 microns
using a DLS instrument.
Examples 5-8: Large (30 Micron) Reloadable Capsules with Different
Core Solvents
[0328] Capsules 5-8 of this invention were prepared following the
same procedure described in Example 4 except that different core
solvents were used.
[0329] Capsule 5 was prepared using 60 g of triacetin and 180 g of
NEOBEE oil.
[0330] Capsule 6 was prepared using 60 g of triacetin and 180 g of
isopropyl myristate.
[0331] Capsule 7 was prepared using 60 g of triethyl citrate and
180 g of isopropyl myristate.
[0332] Capsule 8 was prepared using 60 g of triethyl citrate and
180 g of NEOBEE oil.
[0333] Each of Capsules 5-8 had an average particle size of 30
microns measured using an DLS instrument.
[0334] The Hansen solubility parameters of the core solvents are
shown in Table 3 below.
[0335] In some embodiments, the hydrophilic core solvent has a
water solubility in the range of 0.02 to 300 g/L (e.g., 0.1 to 200
g/L and 1 to 100 g/L) and a weighted Hansen solubility parameter of
18 or greater. In other embodiments, the hydrophilic core solvent
has a Hansen polarizability (dP) of 4 or greater and a Hansen
h-bonding value (dH) of 5 or greater. In still other embodiments,
the hydrophobic core solvent has a weighted Hansen solubility
parameter of 18 or less, a Hansen polarizability (dP) of 4 or less,
and a Hansen h-bonding value (dH) of 5 or less. The core solvents
used to prepare Capsules 1-8 fall within the above described
ranges.
TABLE-US-00003 TABLE 3 Hansen Solubility Parameters Weighted Hansen
Water solubility Solubility Solvent .delta.D .delta.P .delta.H
parameter (mg/L) Preferred hydrophilic -- >4 >5 >18
1000-100,000 core solvent triethyl citrate 16.9 6.4 10.2 20.8 65000
triacetin 16.4 5.7 9.6 19.8 21520 Preferred hydrophobic -- <4
<5 <18 <1 core solvent Neobee oil 16.5 2.5 3.3 17 0.014
isopropyl myristate 16 2.1 2.7 16.4 <0.1
Examples 9-12: Performance of Large Reloadable Capsules in an
Alcohol Body Spray Base
[0336] To establish the consumer benefit of reloadable
microcapsules, Capsules 4-7 each were mixed with fragrance Apple
and then added to an alcohol body spray base (95 wt % ethanol/5 wt
% water) to obtain four microcapsule compositions, i.e., S4-S7
respectively. Each microcapsule composition contained by weight
1.5% fragrance, 4.7% capsule slurry and 93.8% alcohol body spray
base.
[0337] A control composition, i.e., Comparative Composition S2',
was prepared by mixing 1.5% fragrance Apple alone with the alcohol
body spray base.
[0338] Each of S4-S7 and S2' (0.5 g) was sprayed onto a lycra
clothes. The clothes were allowed to dry for 24 hours. A panel of 7
judges evaluated the samples and rated the fragrance intensity both
prior to rubbing (pre-rubbing) the clothes and after rubbing it
(post-rubbing) for 5 times. The fragrance intensity was rated at a
scale ranging from 0 to 10. A numerical value of 2 indicates that
the composition produces a weak intensity. A value of 10 indicates
that the composition generates a very strong smell.
[0339] The sensory results are given in Table 4. The analysis
indicated that reloadable capsule compositions (S4-S7) provided
significantly greater pre-rubbing and post-rubbing fragrance
intensity as compared to neat fragrance in Comparative Composition
S2').
TABLE-US-00004 TABLE 4 Core Solvents Pre-rubbing Post-rubbing
Hydrophilic/ fragrance fragrance Samples hydrophobic V/V intensity
intensity S4 Triethyl citrate/Neobee 4.50 5.57 oil; 50:50 S5
Triacetin/Neobee oil; 25:75 3.14 4.14 S6 Triacetin/Isopropyl 3.29
4.5 myristate; 25:75 S7 Triethyl citrate/Isopropyl 4.14 5.07
myristate; 25:75 S2' No core solvents 2.14 2.86
Example 13: Performance of Large Reloadable Capsules in an Aerosol
Base
[0340] The slurry of Capsule 4 was mixed with fragrance Apple and
then added to an aerosol base to obtain microcapsule composition
S8. Table 5 below shows the components of S8.
[0341] A control composition, i.e., Comparative Composition S3',
was prepared by mixing 1.5% fragrance Apple alone with the aerosol
base.
[0342] Each of S8 and S3' (1 g) was sprayed onto a forearm of a
panelist. After 5 hours, the panelist was instructed to briefly rub
the forearm and rate the fragrance intensity (post-rubbing) at a
scale ranging from 0 to 100. A numerical value of 6 indicates that
the composition produces a weak intensity. A value of 17 indicates
that the composition generates a strong smell. A value of 35
designates a very strong smell.
[0343] The sensory results are shown in Table 6. The analysis
indicated that reloadable capsule composition S8 provided
significantly greater post-rubbing fragrance intensity as compared
to neat fragrance in Comparative Composition S3').
TABLE-US-00005 TABLE 5 Component Description % A46 Propellant 55
(Butane/Isobutane Mix) Alcohol Diluent 38.8 Fragrance Perfume 1.5
Capsule Technology 4.7
TABLE-US-00006 TABLE 6 Samples Post-rubbing intensity S3' 8.68 S8
13.86
Example 14: Performance in an Alcohol Body Spray Base
[0344] The following evaluation shows the benefit of using
reloadable capsules to delivery aldehyde fragrance ingredients. It
is known that aldehydes react with microcapsule wall-forming
materials such as polyisocyanate and polyamine. Encapsulating
aldehydes or alcohols using polyurea chemistry is very challenging.
The following example provides an effective method to deliver an
aldehyde-containing fragrance using reloadable microcapsules.
[0345] The slurry of Capsule 4 was mixed with a research fragrance
containing an aldehyde (i.e., Fragrance D), and then blended into
an aerosol base to obtain microcapsule composition S9, which
contains 1.5% fragrance, 4.7% Capsule 4, and 93.8% alcohol body
spray base (95% ethanol/5% water). For comparison, Comparative
Composition S4' was prepared using Fragrance D alone at 1.5% in the
alcohol body spray base.
[0346] Each of S9 and S4' (0.5 g) was sprayed onto a piece of lycra
clothes. The piece of clothes was allowed to dry for 24 hours. A
panel of 9 judges evaluated the samples and rated the fragrance
intensity both prior to rubbing (pre-rubbing) the clothes and after
rubbing it (post-rubbing) for 5 times. The fragrance intensity was
rated at a scale ranging from 0 to 10. A numerical value of 2
indicates that the composition produces a weak intensity. A value
of 10 indicates that the composition generates a very strong
smell.
[0347] The sensory results are given in Table 7. The analysis
indicated that reloadable capsule composition S9 successfully
delivered aldehyde-containing fragrance and provided significantly
greater pre-rubbing and post-rubbing fragrance intensity as
compared to neat fragrance in Comparative Composition S4').
TABLE-US-00007 TABLE 7 Pre-rubbing Post-rubbing Samples intensity
intensity S4' 3.06 4.06 S9 3.67 5.33
Examples 15: Diffusion of the Fragrance and Hydrophilic Core
Solvent
[0348] When mixing reloadable microcapsule Capsule 4 with a
fragrance, the hydrophilic core solvent (i.e., triethyl citrate)
can diffuse out of the reloadable microcapsule and the fragrance
can diffuse into the microcapsule.
[0349] To determine the amount of the hydrophilic core solvent and
fragrance that diffuse through the microcapsule wall, two
microcapsule compositions S10 and S11 were prepared by mixing the
following components:
[0350] S10:1.5% Model Fragrance A, 4.7% Capsule 4 slurry, and 93.8%
an alcohol body spray base (95% ethanol/5% water); and
[0351] S11: 1.5% Model Fragrance B, 4.7% Capsule 4 slurry, and
93.8% an alcohol body spray base (95% ethanol/5% water).
[0352] The two microcapsule compositions were allowed to sit at the
room temperature for 5 days to reach the equilibrium. For each of
S10 and S11, the capsules were filtered out of the base using a 1
micron glass microfiber syringe filter (Whatman). The filtrate was
collected and analyzed using a gas chromatograph (GC). The % of
diffused fragrance was calculated as (Initial fragrance wt %-wt %
fragrance in the filtrate)/initial fragrance wt %.times.100%. The %
of diffused triethyl citrate was calculated as (Initial amount of
triethyl citrate--the amount of triethyl citrate in the
filtrate)/Initial amount of triethyl citrate.times.100%. S2'
described above was also analyzed as a control (data not shown in
Table 8). Table 8 below provides the results for the diffusion
experiment.
TABLE-US-00008 TABLE 8 S10 S11 % of diffused % of diffused % of
diffused % of diffused fragrance triethyl citrate fragrance
triethyl citrate 6.7 85.3 6.7 85.3
Example 16: Melamine Formaldehyde Reloadable Microcapsule
[0353] A melamine-formaldehyde reloadable microcapsule, i.e.,
Capsule 9, was prepared following the procedure described in
Example 2 of U.S. Pat. No. 7,119,057. See also U.S. Pat. No.
7,196,049.
[0354] In brief, a copolymer of acrylamide and acrylic acid was
first dispersed in water together with a methylated
melamine-formaldehyde resin to obtain a polymer solution. A mixture
of Neobee oil/triethyl citrate oil was then added into the solution
with high speed shearing to form small droplets. Curing of the
polymeric film over the oil droplets as capsule wall affected by
increasing the solution pH to polymerize the polymers followed by
heating the solution to 50 to 125.degree. C.
[0355] Melamine-formaldehyde reloadable microcapsule thus prepared
in a slurry contained in the microcapsule core by weight a mixture
of 30% triethyl citrate and 70% Neobee oil. The microcapsule core,
free of an active material, constituted 32% by weight of the
microcapsule slurry. Different triethyl citrate/Neobee oil weight
ratio can be use, e.g., at a range of 20/80 to 50/50.
Example 17: Polyurea Reloadable Microcapsule
[0356] A polyurea reloadable microcapsule, i.e., Capsule 10, was
prepared following the procedure below. See also U.S. Pat. No.
8,299,011 B2, Example 1.
[0357] Step 1. Preparation of the oil-in-water emulsion. One
hundred twenty grams of a Neobee/triethyl citrate oil mixture was
weighed out and combined with 9.6 g of isocyanate monomer,
Lupranate.TM. M20 (BASF corporation, Wyandotte, Mich., USA) to form
the oil phase. In a separate beaker, a 3% surfactant solution (160
g) was prepared by dissolving 4.8 g of Mowet D-425 (Akzo Nobel,
Fort Worth, Tex., USA) in water. The oil phase was then emulsified
into the aqueous phase to form an oil-in-water emulsion under
shearing (Ultra Turrax.RTM., T25 Basic, IKA.TM., WERKE) at 6500 rpm
for two minutes.
[0358] Step 2. Formation of fragrance capsules. To the oil-in-water
emulsion was added 10.8 g of 40% hexamethylene diamine (HMDA)
(INVISTA, Wichita, Kans., USA) under agitation. The resultant
capsule slurry was cured at room temperature for three hours to
obtain Capsule 10.
[0359] Capsule 10 thus prepared had (i) a polyurea microcapsule
wall and (ii) a microcapsule core consisting of triethyl citrate as
the hydrophilic core solvent and Neobee oil as the hydrophobic core
solvent. The weight ratio between triethyl citrate and Neobee oil
is 30:70.
Examples 18-21: Performance in a Liquid Detergent
[0360] To determine the performance of Capsules 9 and 10, four
microcapsule compositions (i.e., S12-15) were prepared by mixing
each of the two capsules slurry obtained in the examples above with
a research fragrance (i.e. Fragrance E) and a liquid detergent base
(i.e., unfragranced Liquid Tide, commercially available from the
Procter & Gamble Company, Cincinnati, Ohio) as follows:
[0361] S12: 0.5% fragrance E, 9.5% Capsule 9 slurry, and 90% Liquid
Tide;
[0362] S13: 0.5% fragrance E, 9.5% Capsule 9 slurry containing on a
solid basis 2% polyquaternium-47 (Merquat.TM. 2001, Lubrizol
Corporation, Wickliffe, Ohio), and 90% Liquid Tide;
[0363] S14: 0.5% fragrance E, 9.5% Capsule 10 slurry, and 90%
Liquid Tide; and
[0364] S15: 0.5% fragrance E, 9.5% Capsule 10 slurry containing on
a solid basis 1% polyquaternium-6 (Merquat 100, Lubrizol) and 1.5%
polyvinyl amine (Lupamin 9095, BASF), and 90% Liquid Tide.
[0365] The above compositions were aged for 4 weeks at 45.degree.
C.
[0366] A control composition, i.e., Comparative Composition S5',
was prepared by mixing 0.5% Fragrance E alone with Liquid Tide.
[0367] Each of S12-15 and S5' (1 g) was evaluated by conducting a
laundry experiment using a US wash machine. In the wash 40 grams of
a sample was dosed. Terry towels were washed and then air-dried for
16 hours before being evaluated by a panel of 12 judges. The
fragrance intensity was rated with an LMS scale ranging from 0 to
50. A numerical value of 5 suggests that the fabric only produce a
very week intensity while a value of 30 indicates that the subject
generates a strong smell, and a value of 50 indicates a very strong
smell. The sensory results are shown in Table 9.
[0368] The analysis indicated that reloadable capsule compositions
S12-15 provided significantly greater post-rubbing fragrance
intensity as compared to neat fragrance in Comparative Composition
S5'.
TABLE-US-00009 TABLE 9 Post-rubbing Sample fragrance intensity S5'
4.1 S12 6.9 S13 8.4 S14 5.0 S15 6.4
Examples 22-25: Performance in a Fabric Softener
[0369] To determine the performance of Capsules 9 and 10 in a
fabric softener, four microcapsule compositions (i.e., S16-19) were
prepared by mixing each of the capsule slurries prepared in the
examples above with a research fragrance (i.e. Fragrance F) and a
liquid fabric softener base (i.e., unfragranced Downy, commercially
available from the Procter & Gamble Company, Cincinnati, Ohio)
as follows:
[0370] S16: 0.5% fragrance F, 9.5% Capsule 9 slurry, and 90%
Downy;
[0371] S17: 0.5% fragrance F, 9.5% Capsule 9 slurry containing on a
solid basis 2% polyquaternium-47 (Merquat.TM. 2001 commercially
available from Lubrizol Corporation, Wickliffe, Ohio), and 90%
Downy;
[0372] S18: 0.5% fragrance F, 9.5% Capsule 10 slurry, and 90%
Downy; and
[0373] S19: 0.5% fragrance F, 9.5% Capsule 10 slurry containing on
a solid basis 1% polyquaternium-6 (Merquat 100 from Lubrizol) and
1.5% polyvinyl amine (Lupamin 9095, from BASF), and 90% Downy.
[0374] The above compositions were aged for 4 weeks at 45.degree.
C.
[0375] A control composition, i.e., Comparative Composition S6',
was prepared by mixing 0.5% Fragrance F alone with Downy.
[0376] Each of S12-15 and S5' (1 g) was evaluated by conducting a
laundry experiment with a US washing protocol in a US wash machine.
After terry towels were washed with an unfragranced Liquid Tide, 35
grams of each fabric softener (i.e., each of S16-19) was added at
the rinse stage. The terry towels were air-dried for 16 hours and
then evaluated by a panel of 12 judges. The fragrance intensity was
rated by an LMS scale ranging from 0 to 50. A numerical value of 5
suggests that the fabric only produce very week intensity while a
value of 30 indicates that the subject generates a strong smell,
and a value of 50 indicates a very strong smell. The sensory
results are shown in Table 10.
TABLE-US-00010 TABLE 10 Post-rubbing Sample fragrance intensity S6'
3.8 S16 7.2 S17 8.3 S18 5.9 S19 5.8
[0377] The analysis indicated that reloadable capsule compositions
S16-19 provided significantly greater post-rubbing fragrance
intensity as compared to neat fragrance in Comparative Composition
S6').
Examples 26-27: Polyurea Reloadable Microcapsule--Ethanol
Charged
[0378] To determine the benefit of ethanol charged capsules,
Capsule 4 was mixed with both ethanol and fragrance in the below
ratios, creating new capsules slurries (Capsules 11 and 12) and
allowed to equilibrate for 2 days before use in both fabric
softener and body lotion applications. Ethanol charged Capsule 11
was prepared by mixing 30 g of capsule 4 with 30 g of ethanol and
4.8 g of Fragrance Apple and allowing the mixture to stand for 2
days before use in the application. Capsule 12 was prepared by was
prepared by mixing 6.25 g of capsule 4 with 2 g of ethanol and 2.75
g of Fragrance Apple and allowing the mixture to stand for 2 days
before use in the application.
Examples 28-29: Performance of Ethanol Charged Polyurea Reloadable
Microcapsule in Body Lotion
[0379] To determine the performance of Capsule 11, two microcapsule
compositions (i.e., S20-21) were prepared by mixing the Capsule 11
slurry into body lotion base (i.e., unfragranced Lubriderm,
commercially available from the Johnson & Johnson Consumer
Products Company, Skillman, N.J.) as follows: (i) S20 (uncharged):
2% Fragrance Apple, 12.5% Capsule 4 slurry, and 85.5% Lubriderm
body lotion, (ii) S21 (ethanol charged): 12.5% Capsule 4 slurry,
12.5% ethanol, and 73% Lubriderm body lotion. The above
compositions were aged for 3 days at room temperature.
[0380] A control composition, i.e., Comparative Composition S6',
was prepared by mixing 2% Apple Fragrance alone with 98% Lubriderm
body lotion.
[0381] Each of S20-21 and S6' (0.35 g) were applied to a blotter
and evaluated after 24 by a panel of 8 judges for post rub
fragrance intensity. The fragrance intensity was rated by a scale
ranging from 0 to 10. A numerical value of 2 suggests that the
blotter only produce very week intensity while a value of 5
indicates that the subject generates a moderately strong smell, and
a value of 8 indicates a very strong smell. The sensory results are
shown in Table 11.
TABLE-US-00011 TABLE 11 Post-rubbing Sample fragrance intensity S6'
4.87 S20 6.56 S21 7.9
[0382] The analysis indicated that ethanol charged reloadable
capsule compositions S21 provided significantly greater
post-rubbing fragrance intensity as compared to neat fragrance
(Comparative Composition S6') or the capsule without ethanol charge
(Comparative Composition S20').
Examples 30-32: Performance of Ethanol Charged Polyurea Reloadable
Microcapsule in a Fabric Softener
[0383] To determine the performance of Capsule 12 in a fabric
softener, two microcapsule compositions (i.e., S22-23) were
prepared by mixing each of the capsule slurries prepared in the
examples above with an Apple fragrance and a liquid fabric softener
base (i.e., unfragranced Downy, commercially available from the
Procter & Gamble Company, Cincinnati, Ohio) as follows:
[0384] S22: 0.423% Fragrance Apple, 1.5% Capsule 4 slurry, and
98.07% Downy; and
[0385] S23: 4.1% Capsule 12 slurry, and 95.9% Downy
[0386] The above compositions were aged for 4 weeks at 37.degree.
C.
[0387] A control composition, i.e., Comparative Composition S6',
was prepared by mixing 0.423% Fragrance Apple alone with Downy.
[0388] Each of S22-23 and S6' (40 g) was evaluated by conducting a
laundry experiment with a US washing protocol in a US wash machine.
After terry towels were washed with an unfragranced Liquid Tide, 40
grams of each fabric softener (i.e., each of S22-23 and S6') was
added at the rinse stage. The terry towels were then placed in a
drying cabinet at 75.degree. F. for 4 hours and then evaluated by a
panel of 7 judges. The fragrance intensity was rated by a scale
ranging from 0 to 10. A numerical value of 2 suggests that the
fabric only produce very week intensity while a value of 5
indicates that the subject generates a moderately strong smell, and
a value of 8 indicates a very strong smell. The sensory results are
shown in Table 12.
TABLE-US-00012 TABLE 12 Post-rubbing Sample fragrance intensity S6'
1.83 S22 3.67 S23 4.25
[0389] The analysis indicated that reloadable capsule compositions
S23 provided significantly greater post-rubbing fragrance intensity
as compared to neat fragrance (Comparative Composition S6') or the
capsule without ethanol charge (Comparative Composition S22').
Example 33: Body Mist
[0390] A stable capsule suspension, i.e., S24, was prepared using a
visco-stable hydro-alcohol base. Specifically, 0.25 g of Ultrez 20
(a crosspolymer of acrylates/C.sub.10-C.sub.30 alkyl acrylate,
Lubrizol) was slowly added to 20.75 g of water with mixing,
followed by the addition of 70 g of SD alcohol 40 (denatured
alcohol) to obtain an Ultra20 hydro-alcohol solution. Subsequently,
a slurry of Capsule 4 (5 g) was added and mixed until uniform, to
which was then added 4 g of Model Fragrance C. The viscosity of the
resultant mixture was adjusted with AMP-Ultra PC 2000 (95%
Aminomethyl Propanol (AMP)--Angus Chemical Company) to a viscosity
of 350-500 cP. The viscosity was measured using a Brookfield with
spindle #4 at a motor speed of 60 RPM. A control composition, i.e.,
Comparative Composition S24', was prepared similarly except that no
capsule slurry was added. Table 13 and 14 below shows the
components of S24 and S24' respectively.
[0391] Each of S24 and S24' (0.35 g) was sprayed onto a forearm of
a panelist. After 5 hours, the panelist was instructed to briefly
rub the forearm and rate the fragrance intensity at a scale ranging
from 0 to 100. A numerical value of 6 indicates that the
composition produces a weak intensity. A value of 17 indicates a
strong smell. A value of 55 designates a very strong smell.
[0392] S24 had a post-rubbing intensity of 10.4. Comparative
Composition S24' had a post-rubbing intensity of 6.9.
TABLE-US-00013 TABLE 13 S24 Component Description % Ultrez 20
Rheology modifier 0.25 Water Base 20.75 95% Ethanol Base 70 Capsule
Reloadable capsule 5 Model Fragrance C Perfume 4
TABLE-US-00014 TABLE 14 S24' Component Description % Ultrez 20
Rheology modifier 0.25 Water Base 25.75 95% Ethanol Base 70 Model
Fragrance C Perfume 4
Example 34: A Reloadable Polyacrylate Capsule with a Mixture of 50%
Neobee Oil and 50% Triethyl Citrate as the Hydrophobic Core
Solvent
[0393] A reloadable microcapsule of this invention, i.e., Capsule
Composition 34, was prepared following the procedure described
below. More specifically, 160 g of a 50:50 mixture of NEOBEE oil
(Stepan, Chicago, Ill.; a mixture of caprylic/capric triglycerides)
and triethyl citrate (Citroflex 2 Vertellus Performance materials,
Greensboro, N.C.) was weighed out and combined with 20 g of
ethylene glycol dimethacrylate (VISIOMER.RTM. EGDMA SG, Evonik CRYO
LLC, Parsippany, N.J.) to form an oil phase. In a separate beaker,
a 200 g aliquot of a 2% partially hydrolyzed polyvinyl alcohol
solution was prepared by mixing water and SELVOL Ultlux.RTM. FA
commercially available from Sekisui Specialty Chemicals America
LLC, Dallas, Tex. The oil phase was then emulsified into the 2%
partially hydrolyzed polyvinyl alcohol solution to form an
oil-in-water emulsion under shearing (ULTRA TURRAX, T25 Basic, IKA
WERKE) at 3000 rpm for three minutes.
[0394] The oil-in-water emulsion was placed in a round bottom
vessel, sealed and purged with nitrogen gas while mixing at 350 RPM
until no dissolved oxygen was detected using a dissolved oxygen
meter. In a separate vessel, a solution of 3% ammonium persulfate
(PeroxyChem, Philadelphia, Pa.) and 4% sodium metabisulfite (BASF
CORPORATION, Florham Park, N.J.) was prepared using N.sub.2 purged
water containing no dissolved oxygen as determine by a dissolved
oxygen meter. A 20 g aliquot of this purged ammonium persulfate and
sodium metabisulfide solution was added to the purged oil-in-water
emulsion. The resultant mixture was blanketed with nitrogen, sealed
and mixed for 15 minutes at 25.degree. C. to ensure uniformity. The
temperature was then raised to 65.degree. C. and cured for 3.5
hours to obtain Capsule Composition 34. The composition was cooled
to 25.degree. C. and analyzed for free oil, particle size and
performance. The average size of the capsule was measure to be in
the range of 10 to 20 microns using a dynamic light scattering
(DLS) instrument.
Example 35: Performance of Polyacrylate Reloadable Capsules in an
Alcohol Body Spray Base
[0395] To establish the consumer benefit of reloadable
microcapsules, Capsule 34 was mixed with fragrance Apple
(commercially available from International Flavors &
Fragrances, Union Beach, N.J.) and then added to an alcohol body
spray base (95 wt % ethanol/5 wt % water) to obtain a body spray
sample, i.e., S34. The sample contained by weight 1.5% fragrance,
4.7% Capsule Composition 34, and 93.8% alcohol body spray base.
[0396] A control sample, i.e., Comparative S34', was prepared by
mixing 1.5% fragrance Apple alone with the alcohol body spray
base.
[0397] Each of S34 and S34' (0.5 g) was separately sprayed onto a
Lycra cloths. The cloths were allowed to dry for 24 hours. A panel
of 8 judges evaluated the samples and rated the fragrance intensity
both prior to rubbing (pre-rubbing) the clothes and after rubbing
it (post-rubbing) 5 times. The fragrance intensity was rated at a
scale ranging from 0 to 10. A numerical value of 2 indicates that
the composition produces a weak intensity. A value of 10 indicates
that the composition generates a very strong smell.
[0398] The sensory results are given in Table 15. The analysis
indicated that reloadable capsule compositions (S34) provided
significantly greater pre-rubbing and post-rubbing fragrance
intensity as compared to neat fragrance in Comparative Composition
S34'.
TABLE-US-00015 TABLE 15 Pre-rubbing Post-rubbing fragrance
fragrance Samples intensity intensity S34 3.5 4.75 S34' 2.56
2.88
Example 36: A Reloadable Silica Capsule with a Mixture of 50%
Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core Solvent
[0399] A reloadable microcapsule of this invention, i.e., Capsule
Composition 36, was prepared following the procedure described
below. Specifically, 232.5 g of a 50:50 mixture of NEOBEE oil
(Stepan, Chicago, Ill.; a mixture of caprylic/capric triglycerides)
and triethyl citrate (Citroflex 2 Vertellus Performance materials,
Greensboro, N.C.) was weighed out to form an oil phase. In a
separate beaker, a 135 g of a 1% Cetyl trimethyl ammonium chloride
(Sigma Aldrich, Saint Louis, Mo.) was prepared using water. The oil
phase was then emulsified into the surfactant solution to form an
oil-in-water emulsion under shearing (ULTRA TURRAX, T25 Basic, IKA
WERKE) at 15000 rpm for three minutes.
[0400] The oil-in-water emulsion was placed in a round bottom
vessel and mixed at 350 RPM. The pH of the mixture was evaluated
and adjusted to 3.8. Water was added to the vessel bringing a total
sample weight to 559.74 g. A 40.26 g aliquot of Tetraethyl
orthosilicate (Dynasylan.RTM. TEOS UHP, Evonik Degussa Corporation,
Parsippany, N.J.) was then added to the mixture while mixing. The
resultant mixture was agitated at 350 RPM for 48 hours at
25.degree. C. to obtain Capsule Composition 36.
Example 37: Performance of Silica Reloadable Capsules in an Alcohol
Body Spray Base
[0401] Capsule Composition 36 was mixed with a model fragrance
having a high vapor pressure and then added to an alcohol body pray
base (95 wt % ethanol/5 wt % water) to obtain a body spray sample,
i.e., S37. The sample contained by weight 4% fragrance, 16% Capsule
Composition 36 and 80% alcohol body spray base.
[0402] A control sample, i.e., Comparative S36', was prepared by
mixing 4% of the model fragrance with the alcohol body spray
base.
[0403] Each of S36 and S36' (0.5 g) was sprayed onto a Lycra
cloths. The cloths were allowed to dry for 24 hours. A panel of 6
judges evaluated the samples and rated the fragrance intensity both
prior to rubbing (pre-rubbing) the clothes and after rubbing it
(post-rubbing) 5 times. The fragrance intensity was rated at a
scale ranging from 0 to 10. A numerical value of 2 indicates that
the composition produces a weak intensity. A value of 10 indicates
that the composition generates a very strong smell.
[0404] The sensory results are given in Table 16. The analysis
indicated that reloadable capsule compositions (S36) provided
significantly greater pre-rubbing and post-rubbing fragrance
intensity as compared to neat fragrance in Comparative S36'.
TABLE-US-00016 TABLE 16 Pre-rubbing Post-rubbing fragrance
fragrance Samples intensity intensity S36 5 5.17 S36' 3 3.83
Example 38: A Reloadable Polyurea Capsules with a Mixture of 50%
Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core Solvent
(Particle Size: 30 Microns)
[0405] Capsule Composition C38 of this invention was prepared
following the procedure below. NEOBEE oil (120 g, the hydrophobic
solvent) and triethyl citrate (Citroflex 2 Vertellus Performance
materials, Greensboro, N.C.) (120 g, the hydrophilic solvent) were
combined with 4.8 g of isocyanate monomer, LUPRANATE M20 to form an
oil phase. In a separate beaker, a 0.5% surfactant solution (319.2
g) was prepared by dissolving 1.6 g of Mowiol 3-85, a partially
hydrolyzed polyvinyl alcohol (Kuraray, Houston, Tex.) in water. The
oil phase was then emulsified into the surfactant solution to form
an oil-in-water emulsion under shearing (ULTRA TURRAX, T25 Basic,
IKA WERKE) at 3000 rpm for three minutes. To the oil-in-water
emulsion was added 36 g of 6% HMDA aqueous solution under
agitation. The capsule slurry was cured at 55.degree. C. for three
hours to obtain Capsule Composition C38. The average particle size
of the capsule was measure to be 30 microns using a DLS
instrument.
Example 39: Mosquito Repellency Evaluation for Reloadable Polyurea
Capsules Evaluated in the Presence of DEET
(N,N-Diethyl-Meta-Toluamide)
[0406] Two 100 g insect repellent samples were prepared each
containing a commercial DEET product (SCJ OFF Family care
containing 7% DEET). Sample S38-1 was dosed with 10% of Capsule
Composition C38. Sample S38-2 was dosed with 20% of Capsule
Composition C38. Each sample was separately added to a pump spray
bottle and allowed to equilibrate for 3 days. The samples were
evaluated for their ability to repel mosquitos in blood well tests.
The commercial DEET product without capsules was used as a control
sample (S38'). The results were shown in Table 17 below. Samples
S38-1 and S38-2 showed significant improvement over the control
sample in mosquito repellency.
TABLE-US-00017 TABLE 17 Samples Repellency.sup.20 S38-1 87% S38-2
94% S38' 56%
Example 40: A Reloadable Gelatin Capsules with a Mixture of 50%
Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core Solvent
(Particle Size: 30 Microns)
[0407] Capsule Composition 40 of this invention was prepared
following the procedure below. Gelatin capsules
(diameter.about.30-50 microns) were prepared by first dissolving 4
g of gelatin 225 bloom into 200 g of hot water. Gelatin was stirred
using a top down IKA-Werke at 400 RPM for 20 min. Water was
maintained at temperatures between 50-65.degree. C. to allow the
gelatin to become fully hydrated. While mixing, 21.5 g of 25%
(wt/wt) solution of gum Arabic Senegal followed by addition of 50 g
of a 50:50 mixture of NEOBEE oil (Stepan, Chicago, Ill.; a mixture
of caprylic/capric triglycerides) and triethyl citrate (Citroflex 2
Vertellus Performance materials, Greensboro, N.C.). The resultant
solution was homogenized at 6500 RPM using a homogenizer for 1
minute. The resultant mixture was stirred at 400 RPM for 5 minutes,
adjusted to pH 3.1-3.25, and heated to 50.degree. C. under
agitation for 1 to 2 hours to obtain Capsule Composition 40.
Capsules could also be placed through a cross-linking post
treatment of giving a more robust capsule using transglutaminase,
gluteraldehyde or other cross-linkers known in the art for gelatin
capsule preparation.
Example 41: A Reloadable Silica/Gelatin Capsules with a Mixture of
50% Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core
Solvent
[0408] A silica/gelatin microcapsule of this invention, i.e.,
Capsule Composition 41, was prepared following the procedure.
Tetraethyl orthosilicate (TEOS) (commercially available from Evonik
Corporation, Piscataway, N.J.) 40 g was added to 36 g 0.01 N
hydrochloric acid and the mixture was stirred at 45.degree. C. for
30 minutes. Additional 376 g TEOS was added dropwise during 1 hour.
The mixture was stirred at 45.degree. C. overnight, and loaded into
a Rotavapor to remove lights with the aid of 10 mmHg vacuum. The
resulting 275 g colorless liquid polysiloxane material (Poly-Si)
was saved and used in capsule preparation. The polysiloxane
materials thus prepared have a viscocity of 5-30 (Brookfield DV1
viscometer, 60 rpm, ambient temperature, spindle 4), and a
molecular weight of between 1000 and 3000.
[0409] A solution of 2 g gelatin A (commercially available from
Great Lakes Gelatin Co., Grayslake, Ill.) in 118 g of water was
heated to 50.degree. C. Gum Arabic (2 g) was added as a 10% aqueous
solution (20), followed by the addition of 40 g of a 50:50 mixture
of NEOBEE oil (Stepan, Chicago, Ill.; a mixture of caprylic/capric
triglycerides) and triethyl citrate (Citroflex 2 Vertellus
Performance materials, Greensboro, N.C.) in 10 g of pretreated
silica Poly-Si. The pH was adjusted to 4.5 with 10% acetic acid
solution. The resultant mixture was stirred with an overhead
stirrer at 600 rpm and cooled slowly to room temperature
(20.degree. C.). Consequently, to the mixture was added a solution
of 6 g of sodium silicate (37.5% aqueous solution, commercially
available from PQ Corp., Malvern, Pa.) in 80 g of water. After the
pH was adjusted to 6.6, the resultant mixture was stirred for 1
hour at room temperature to obtain Capsule 5. The amount of
precursor (e.g., pretreated silica Poly-Si as used in this example)
was routinely determined by the wall polymer level needed and was
generally 5% to 50% of the final formulation. A skilled person in
the art would be able to adjust the precursor amount, without undue
experimentation, to prepare microcapsules having a desirable wall
thickness and release profile.
Example 42: A Reloadable Polyurea/Silica Capsule with a Mixture of
50% Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core
Solvent
[0410] A polyurea/silica hybrid microcapsule composition of this
invention, i.e., Capsules Composition 42, was prepared following
the procedure. 240 g of a 50:50 mixture of NEOBEE oil (Stepan,
Chicago, Ill.; a mixture of caprylic/capric triglycerides) and
triethyl citrate (Citroflex 2 Vertellus Performance materials,
Greensboro, N.C.) was mixed in a beaker, 12 g of tetraethyl
orthosilicate (commercially available from Evonik, Essen, Germany),
and 19.2 g of Lupranate M20 (a polymeric methylene diphenyl
diisocyante-based resin containing multiple isocyanate groups,
commercially available from BASF, Wyandotte, Mich.), to form an oil
phase. In a separate beaker, an aqueous solution of 319.2 g of 0.9%
Mowiol 4-98 (a fully hydrolyzed polyvinyl alcohol, commercially
available from Kurary America Inc., Houston, Tex.) and 0.9% Walocel
CRT 50000 PA (sodium carboxymethylcellulose; a co-dispesant
commercially available from Dow, Midland, Mich.) was prepared and
then emulsified with the oil phase to form the fragrance emulsion
under high shearing (IKA-ULTRA TURRAX, T25 Basic) at 9500 rpm for
three minutes. After the fragrance emulsion was heated to
35.degree. C., 4.3 g of hexamethylene diamine ("HMDA," 40% in
water, commercially available from Sigma-Aldrich, St. Louis, Mo.)
and 5.2 g of water was added under constant mixing with an overhead
mixer. After 15 minutes of stirring at 35.degree. C., the capsule
slurry was cured at 55.degree. C. for two hours and then cooled to
room temperature.
Example 43: A Reloadable Polyurea/Silica Capsule with a Mixture of
50% Neobee Oil/50% Triethyl Citrate as the Hydrophobic Core
Solvent
[0411] A polyurea/silica hybrid microcapsule composition, i.e.,
Capsule Composition 43, can be prepared following the procedure. An
aqueous phase is provided by mixing 30 g of 10% Ultalux AD
(Selvol), 100 g of 3% UCARETM Polymer JR-30M (Dow), 3 g of Silamine
2972 (Siltech) and 160.8 g of water. In a separate container, an
oil phase is provided by mixing 240 g of a 50:50 mixture of NEOBEE
oil (Stepan, Chicago, Ill.; a mixture of caprylic/capric
triglycerides) and triethyl citrate (Citroflex 2 Vertellus
Performance materials, Greensboro, N.C.), 12.08 g of
tetraorthosilicate (Evonik) and 11.52 g of a xylylene diisocyanate
adduct 25 polymer (Takenate D110-N, Mitsui Chemicals). The oil
phase is then emulsified into the aqueous phase under a shearing
rate of 3000 to 150000 rpm (e.g., 8000 rpm) for three minutes to
form an oil-in-water fragrance emulsion. The fragrance emulsion is
then heated to 35.degree. C., followed by addition of 5.04 g of
branched polyethylenimine (BASF) and 37.56 g of water under
agitation for 5 minutes. The resultant slurry is cured at
55.degree. C. for two hours to obtain Capsule Composition 43.
Example 44: A Large Reloadable Polyurea Capsules with a Mixture of
49% Neobee Oil/49% Triethyl Citrate and 2% Geraniol as the
Hydrophobic Core Solvent (Particle Size: 30 Microns)
[0412] Capsule Composition 44 of this invention has a primary
alcohol in its core for increased diffusivity of fragrance entering
the core. An oil phase is provided by mixing NEOBEE oil (117.6 g),
triethyl citrate (Citroflex 2 Vertellus Performance materials,
Greensboro, N.C.) (117.6 g), 4.8 g Geraniol, and 4.8 g of
isocyanate monomer, LUPRANATE M20. A 0.5% surfactant solution
(319.2 g) is prepared by dissolving 1.6 g of Mowiol 3-85, a
partially hydrolyzed polyvinyl alcohol (Kuraray, Houston, Tex.) in
water. The oil phase is then emulsified into the surfactant
solution to form an oil-in-water emulsion under shearing at 3000
rpm for three minutes. The oil-in-water emulsion is added 36 g of
6% HMDA aqueous solution. The resultant slurry is cured at
55.degree. C. for three hours to obtain Capsule Composition 44 with
an average particle size of 25-35.
Example 45: A Small Reloadable Polyurea Capsules with a Mixture of
47.5% Neobee Oil/47.5% Triethyl Citrate and 5% Geraniol as the
Hydrophobic Core Solvent (Particle Size: 5-15 Microns)
[0413] Capsule Composition 45 of this invention has a primary
alcohol in its core for increased diffusivity. An oil phase is
provided by mixing NEOBEE oil (114 g) and triethyl citrate
(Citroflex 2 Vertellus Performance materials, Greensboro, N.C.)
(114 g), 12 g of Geraniol, and 19.2 g of isocyanate monomer
(LUPRANATE M20). A 0.5% surfactant solution (319.2 g) is prepared
by dissolving 1.6 g of Mowiol 3-85, a partially hydrolyzed
polyvinyl alcohol (Kuraray, Houston, Tex.) in water. The oil phase
is then emulsified into the surfactant solution to form an
oil-in-water emulsion under shearing at 3000 rpm for three minutes.
The oil-in-water emulsion is added 21.6 g of 40% HMDA aqueous
solution under agitation. The resultant slurry is cured at
55.degree. C. for three hours to obtain Capsule Composition 45 with
a particle size of 5-15.
Example 46: A Perfume Spray Product Containing Microcapsule
Composition
[0414] A perfume spray product, S46-1, was prepared by mixing the
following ingredients:
[0415] Water: 13%
[0416] Ethanol: 70%
[0417] Fragrance: 12%
[0418] Capsule Composition C38: 5%
[0419] A perfume spray product, S46-2, was prepared by mixing the
following ingredients:
[0420] Fragrance: 12%
[0421] Water: 12.2%
[0422] Polyacrylate Crosspolymer-6: 0.8%
[0423] Ethanol: 70%
[0424] Capsule Composition C38: 5%
[0425] A control S46' was prepared by mixing the following
ingredients:
[0426] Water: 8%
[0427] Ethanol: 80%
[0428] Fragrance: 12%
[0429] The perfume spray products S46-1, S46-2, and S46' were
sprayed onto a forearm of a panelist. At time 0 and after 6 hours,
the forearm was measure for the headspace concentration of the
fragrance. The results are shown in Table 18 below.
TABLE-US-00018 TABLE 18 Skin headspace analysis (ng/L) 0 HR 6 HR
pre-rub 6 HR post S46' 81419 1201 844 S46-1 57480 2451 2666 S46-2
77751 3103 3957
Example 47: Encapsulated DEET
[0430] Capsule Composition C47 of this invention was prepared
following the procedure below. An oil phase was prepared by mixing
126 g of NEOBEE oil, 48 g of DEET (Sigma Aldrich, St. Louis, Mo.),
9.504 g of LUPRANATE M20 (isocyanate monomer). In a separate
beaker, a surfactant solution was prepared by mixing 241.8 g of
water, 29.7 g of a 10% solution of PVP K90 (polyvinylpyrrolidone
having a weight average molecular weight of 360,000, commercially
available from Ashland), and 59.4 g of a 20% solution of Luviquat
PQ-11 (polyquaternium-11 commercially available from BASF, Florham
Park, N.J.). The oil phase was then emulsified into the surfactant
solution to form an oil-in-water emulsion under shearing (ULTRA
TURRAX, T25 Basic, IKA WERKE) at 12500 rpm for three minutes. After
heating the oil-in-water emulsion to 35.degree. C., a 26.136 g of
16.36% HMDA aqueous solution was added under agitation. The
resultant mixture was heated to 55.degree. C., cured for 2 hours,
and then cooled to 25.degree. C., followed by the addition of 6 g
of Aculyn 33A (an alkali-swellable anionic acrylic polymer
emulsion) as a Rheology modifier to obtain Capsule Composition
C47.
Other Embodiments
[0431] All of the features disclosed in this specification may be
combined in any combination. Each feature disclosed in this
specification may be replaced by an alternative feature serving the
same, equivalent, or similar purpose. Thus, unless expressly stated
otherwise, each feature disclosed is only an example of a generic
series of equivalent or similar features.
[0432] Indeed, to achieve the purpose of preparing a reloadable
microcapsule and a composition containing the reloadable
microcapsule, one skilled in the art can choose different
wall-forming materials/encapsulating polymers, hydrophilic core
solvents, hydrophobic core solvents, external hydrophilic solvents,
active materials, and/or capsule formation aids/catalysts, varying
the concentrations of these wall-forming materials and/or catalysts
to achieve desirable thickness of the wall/diffusion
rate/organoleptic or release profiles in a consumer product.
Further, the ratios among their wall-forming materials, capsule
forming aids, adjuvants, core modifiers, active materials, and
catalysts can also be determined by a skilled artisan without undue
experimentation.
[0433] From the above description, a skilled artisan can easily
ascertain the essential characteristics of the present invention,
and without departing from the spirit and scope thereof, can make
various changes and modifications of the invention to adapt it to
various usages and conditions. Thus, other embodiments are also
within the claims.
* * * * *