US4855144A
Expired / Lapsed
US
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Synthetic melanin aggregates
Assignee: Amcol International Corp
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Filing: 1988-06-14
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Granted: 1989-08-08
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Expires: 2008-06-14
Abstract
Abstract Melanin compositions include a melanin pigment incorporated within polymeric particles, usually within an internal pore network defined by a polymeric particle matrix. The melanin compositions may be produced by in situ oxidation of melanin precursors within the pore network, or by absorption of a melanin pigment in a suitable vehicle or carrier. The melanin compositions are found to display enhanced absorbance of ultraviolet radiation and better cosmetic attributes when compared to melanin pigments which are not incorporated in such a polymeric particle matrix.
Inventors
- 👤 Helen Leong
- 👤 Martin Katz
- 👤 Ann Delk
- 👤 Sergio Nacht
- 👤 David Berliner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 01:24
CPC Classifications
C; C08; C08K; C08K5/00; A; A61; A61K; A61K8/00; A61K8/02; A61K8/0241; A61K8/0283; A61K8/18; A61K8/72; A61Q; A61Q19/00; A61Q19/04; C08L; C08L25/00; C08L25/02; C08L25/04; C08L25/08; A61K2800/00; A61K2800/40; A61K2800/56
Claims Analysis
Total Claims: 38
Claim 1
Independent Claim
10 words
A composition comprising polymeric particles having melanin pigment entrapped therein.
Claim 2
Dependent Claim
10 words
A composition comprising polymeric particles having melanin pigment entrapped therein.
Claim 3
Dependent Claim
26 words
A composition as in claim 1, wherein said polymeric particles define a network of internal pores and wherein said melanin pigment is entrapped within said pores.
Claim 4
Dependent Claim
14 words
A composition as in claim 1, wherein said polymeric particles are substantially non-collapsible beads.
Claim 5
Dependent Claim
19 words
A composition as in claim 3, wherein said polymeric beads have a cross-linking density of at least about 10%.
Claim 6
Dependent Claim
19 words
A composition as in claim 4, wherein said cross-linking density is in the range from about 20% to 80%.
Claim 7
Dependent Claim
23 words
A composition as in claim 1, wherein said particles have an average diameter in the range from about 5 μm to 100 μm.
Claim 8
Dependent Claim
21 words
A composition as in claim 6, wherein said average diameter is in the range from about 10 μm to 40 μm.
Claim 9
Dependent Claim
27 words
A composition as in claim 2, wherein the melanin pigment is formed in situ by conversion of a melanin precursor within the pores of a preformed bead.
Claim 10
Dependent Claim
22 words
A composition as in claim 8, wherein the melanin precursor is selected from the group consisting of L-dopa, tyrosine, tryptophan, and cysteine.
Claim 11
Dependent Claim
12 words
A composition as in claim 8, wherein the melanin precursor is L-dopa.
Claim 12
Dependent Claim
39 words
A composition as in claim 2, wherein preformed melanin pigment is introduced into the pores of the polymeric particles by absorption of a dispersion or solution of melanin pigment in a suitable carrier, followed by evaporation of the carrier.
Claim 13
Dependent Claim
14 words
A composition as in claim 1, wherein the polymeric particles are a styrene-divinylbenzene copolymer.
Claim 14
Dependent Claim
17 words
A composition as in claim 1, wherein the polymeric particles are a methyl methacrylate-ethylene glycol dimethacrylate copolymer.
Claim 15
Independent Claim
39 words
A method for preparing a melanin particle composition, said method comprising: introducing a melanin precursor into a plurality of polymeric particles each defining a network of internal pores; and oxidizing the melanin precursor to melanin pigment within said pores.
Claim 16
Independent Claim
39 words
A method for preparing a melanin particle composition, said method comprising: introducing a melanin precursor into a plurality of polymeric particles each defining a network of internal pores; and oxidizing the melanin precursor to melanin pigment within said pores.
Claim 17
Dependent Claim
22 words
A method as in claim 14, wherein the melanin precursor is selected from the group consisting of L-dopa, tyrosine, tryptophan, and cysteine.
Claim 18
Dependent Claim
15 words
A method as in claim 14, wherein the oxidation is promoted by an oxidation catalyst.
Claim 19
Dependent Claim
13 words
A method as in claim 16, wherein the oxidation catalyst is an enzyme.
Claim 20
Dependent Claim
11 words
A method as in claim 17, wherein the enzyme is tyrosinase.
Claim 21
Independent Claim
41 words
A method for preparing a melanin particle composition, said method comprising: introducing preformed melanin in a suitable carrier into a plurality of polymeric particles each defining a network of internal pores; and evaporating the carrier from the pores of the particles.
Claim 22
Independent Claim
41 words
A method for preparing a melanin particle composition, said method comprising: introducing preformed melanin in a suitable carrier into a plurality of polymeric particles each defining a network of internal pores; and evaporating the carrier from the pores of the particles.
Claim 23
Dependent Claim
28 words
A method as in claim 19, wherein the preformed melanin is solubilized in the carrier and the method further comprises precipitating solid melanin prior to evaporating the carrier.
Claim 24
Dependent Claim
21 words
A method as in claim 19, wherein the melanin in the carrier is in the form of a finely divided powder.
Claim 25
Independent Claim
27 words
A method for protecting skin from exposure to ultraviolet radiation, said method comprising: applying to the skin a composition comprising polymeric particles having melanin pigment entrapped therein.
Claim 26
Independent Claim
27 words
A method for protecting skin from exposure to ultraviolet radiation, said method comprising: applying to the skin a composition comprising polymeric particles having melanin pigment entrapped therein.
Claim 27
Dependent Claim
14 words
A method as in claim 22, wherein said polymeric particles are substantially non-collapsible beads.
Claim 28
Dependent Claim
19 words
A method as in claim 23, wherein said polymeric beads have a cross-linking density of at least about 10%.
Claim 29
Dependent Claim
19 words
A method as in claim 24, wherein said cross-linking density is in the range from about 20% to 80%.
Claim 30
Dependent Claim
22 words
A method as in claim 23, wherein said beads have an average diameter in the range from about 5 μm to 100μm.
Claim 31
Dependent Claim
19 words
A method as in claim 26, wherein said average diameter is in the range from about 10μm to 40μm
Claim 32
Dependent Claim
27 words
A method as in claim 22, wherein the melanin pigment is formed in situ by conversion of a melanin precursor within the pores of a preformed bead.
Claim 33
Dependent Claim
22 words
A method as in claim 22, wherein the melanin precursor is selected from the group consisting of L-dopa, tyrosine, tryptophan, and cysteine.
Claim 34
Dependent Claim
12 words
A method as in claim 22, wherein the melanin precursor is L-dopa.
Claim 35
Dependent Claim
31 words
A method as in claim 22, wherein the melanin pigment is introduced into preformed porous beads by absorption of melanin pigment in a suitable carrier, followed by evaporation of the carrier.
Claim 36
Dependent Claim
28 words
A method as in claim 31, wherein the preformed melanin is solubilized in the carrier and the method further comprises precipitating solid melanin prior to evaporating the carrier.
Claim 37
Dependent Claim
14 words
A method as in claim 22, wherein the polymeric beads are a styrene-divinylbenzene copolymer.
Claim 38
Dependent Claim
17 words
A method as in claim 22, wherein the polymeric beads are a methyl methacrylate-ethylene glycol dimethacrylate copolymer.
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