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Zinc-pyridinethione salts, a process for making thereof and hair care compositions containing them

Assignee: Procter and Gamble Co
•
Filing: 1981-02-03
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Granted: —
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Expires: 2001-02-03
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Abstract

Abstract Heavy metal salts of 1-hydroxy-2-pyridinethione in the form of crystals having defined shape and size, are useful in shampoos, creme rinses and other hair care compositions to deliver antidandruff benefits while not detracting as much as previous pyridinethione salts from the compositions' aesthetics. Hair care compositions containing such salts are also included. A process for producing heavy metal 1-hydroxy-2-pyridinethione salts comprises reacting a water soluble salt of the desired metal with 1-hydroxy-2-pyridinethione or with a water-soluble salt of the pyridinethione in an aqueous surfactant medium.

Inventors

  • 👤 Raymond Edward Bolich, Jr.
  • 👤 Steven Alan Shaya
  • 👤 Christian Steuri

Bibliographic Details

Application Number —
Jurisdiction EP
Data Source google_patents
Last Synchronized 2026-11-02 14:38
CPC Classifications
C; C07; C07D; C07D213/00; C07D213/02; C07D213/89; A; A61; A61K; A61K8/00; A61K8/02; A61K8/18; A61K8/30; A61K8/49; A61K8/4906; A61K8/4933; A61Q; A61Q5/00; A61Q5/006; A61Q5/02; A61K2800/00; A61K2800/40; A61K2800/41; A61K2800/412

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 41 words
A heavy metal salt of 1-hydroxy-2-pyridinethione characterised by being in the form of crystals having a mean sphericity of less than 0.65 and a median equivalent spherical diameter based on volume of at least 2 µm but less than 15 µm.
Claim 2
Dependent Claim 41 words
A heavy metal salt of 1-hydroxy-2-pyridinethione characterised by being in the form of crystals having a mean sphericity of less than 0.65 and a median equivalent spherical diameter based on volume of at least 2 µm but less than 15 µm.
Claim 3
Dependent Claim 26 words
A pyridinethione salt according to Claim 1 characterised in that the heavy'metal is selected from the group consisting of zinc, tin, magnesium, aluminum, cadmium and zirconium.
Claim 4
Dependent Claim 20 words
A pyridinethione salt according to Claim 1 or 2 characterised in that the mean sphericity is from 0.20 to 0.65.
Claim 5
Dependent Claim 25 words
A hair care composition characterised in that it contains from 0.2% to 4.0% of a pyridinethione salt according to any of Claims 1 to 3.
Claim 6
Dependent Claim 27 words
A hair care composition according to Claim 4 characterised by being in the form of a shampoo which additionally contains from 10% to 50% of a surfactant.
Claim 7
Dependent Claim 20 words
A shampoo according to Claim 5 characterised in that it additionally contains from 0.1% to 6.0% of a pearlescent material.
Claim 8
Dependent Claim 35 words
A hair care composition according to Claim 4 characterised by being in the form of a creme rinse which additionally contains from 0.1% to 5.0% of a cationic surfactant and from 95% to 99% water.
Claim 9
Dependent Claim 39 words
A process for making a heavy metal pyridinethione salt characterised by reacting 1-hydroxy-2-pyridinethione or a water soluble salt thereof with a water soluble heavy metal salt in an aqueous surfactant medium, wherein the reaction temperature is at least 20°C.
Claim 10
Dependent Claim 39 words
A process for making a heavy metal pyridinethione salt characterised by reacting 1-hydroxy-2-pyridinethione or a water soluble salt thereof with a water soluble heavy metal salt in an aqueous surfactant medium, wherein the reaction temperature is at least 20°C.
Claim 11
Dependent Claim 33 words
A process according to Claim 8 characterised in that the pyridinethione compound is an alkali metal pyridinethione salt and the concentration of surfactant in the total reaction mixture is from 1% to 24%.
Claim 12
Dependent Claim 42 words
A process according to Claim 8 or 9 characterised in that the heavy metal salt is selected from the group consisting of zinc, tin, magnesium, aluminum, cadmium and zirconium salts and is present in an amount sufficient to provide a stoichiometric excess.
Claim 13
Dependent Claim 53 words
A process according to any of Claims 8 to 10 characterised by reacting sodium 1-hydroxy-2-pyridinethione with a water-soluble zinc salt in an aqueous anionic surfactant medium at a temperature in the range from 60°C to 100 o C, wherein the concentration of surfactant in the total reaction mixture is from 1% to 8%.

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