|Title of Invention||
FAST RELEASE GRANULES
|Abstract||The present invention provides a granule that releases antioxidants rapidly and a method of preparing an antioxidant granule comprising the steps of : (i) melting a non-ionic surfactant the nonionic surfactant having a starting melting point of 40 °C or above as measured by differential scanning calorimetry; (ii) dissolving an antioxidant in the melted non-ionic surfactant with mixing to form a antioxidant/non- ionic solution; (iii) cooling the antioxidant/non-ionic solution to form a solid whilst forming a particulate matter.|
FORM - 2
THE PATENTS ACT, 1970
(39 of 1970)
The Patents Rules, 2003
(See Section 10 and Rule 13)
FAST RELEASE GRANULES
HINDUSTAN UNILEVER LIMITED, a company incorporated under the Indian Companies Act, 1913 and having its registered office at Hindustan Lever House, 165/166, Backbay Reclamation, Mumbai -400 020, Maharashtra, India
The following specification particularly describes the invention and the manner in which it is to be performed
- 1 -FAST RELEASE GRANULES
FIELD OF INVENTION
5 The present invention relates to granule conferring improved delivery of antioxidants to wash liquor.
BACKGROUND OF INVENTION
10 Rapid delivery of adjuncts to a wash medium is important
because it is necessary to have active adjuncts present in the wash liquor for the maximum time so that they perform in the most efficacious manner.
15 GB 1344253 discloses a non-ionic surfactant matrix comprising enzymes.
SUMMARY OF INVENTION
20 The present invention provides a granule that releases an antioxidant rapidly into a wash medium.
In one aspect the present invention provides a granule
comprising: 25 (i) nonionic surfactant, the nonionic surfactant having a starting melting point of 40 °C or above as measured by differential scanning calorimetry; and,
(ii) and an antioxidant, wherein the antioxidant is dissolved in the non-ionic surfactant.
WO 2007/104412 PCT/EP2007/001557
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Preferably the weight ratio of antioxidant to non-ionic is in the range from 1:100 to 20:100, preferably 3:100 to 17:100, most preferably 5:100 to 15:100.
5 The granules are preferably a sieve fraction in the range 18 0 to 14 00 microns.
It is preferred that a laundry detergent powder containing the granules is such that the antioxidant granule is present 10 in the range 0.1 to 5.0 wt %.
In another aspect the present invention provides a method of preparing an antioxidant granule comprising the steps of: (i) melting a non-ionic surfactant the nonxonic surfactant 15 having a starting melting point of 4 0 °C or above as
measured by differential scanning calorimetry; (ii) dissolving an antioxidant in the melted non-ionic
surfactant with mixing to form a antioxidant/non-ionic
solution; 20 (iii) cooling the antioxidant/non-ionic solution to form a
solid whilst forming a particulate matter.
In a further aspect of the present invention there is provided a method of treating a textile with the antioxidant 25 granules of the present invention in an aqueous medium, followed by rinsing and drying the textile.
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DETAILED DESCRIPTION OF THE INVENTION The Granule
The granule is preferably a sieve fraction in the range 180 5 to 1400 microns. The granule is preferably used in a
laundry detergent powder formulation in the range from 0.1 to 5 wt %.
Anti-oxidants are substances as described in Kirk-Othmers
(Vol 3, pg 424) and in Uhlmans Encyclopedia (Vol 3, pg 91)
and CRC Press Oxidation Inhibition in Organic Materials
Vols. I and II, Eds. Jan Pospisil and Peter P. Klemchuk:
15 ISBN 0-8493-4767-X and 0-8493-4768-8.
One class of anti-oxidants suitable for use in the present invention is alkylated phenols having the general formula:
wherein R is C1-C22 linear or branched alkyl, preferably methyl or branched C3-C6 alkyl; C3-C6 alkoxy, preferably methoxy; Rl is a C3-C6 branched alkyl, preferably tert-butyl; x is 1 or 2. Hindered phenolic compounds are
25 preferred as antioxidant.
- 4 -
Another class of anti-oxidants suitable for use in the present invention is a benzofuran or benzopyran derivative having the formula:
wherein Rl and R2 are each independently alkyl or Rl and R2 can be taken together to form a C5-C6 cyclic hydrocarbyl moiety; B is absent or CH2; R4 is C1-C6 alkyl; R5 is
10 hydrogen or -C(0)R3 wherein R3 is hydrogen or C1-C19 alkyl; R6 is C1-C6 alkyl; R7 is hydrogen or C1-C6 alkyl; X is -CH20H, or -CH2A wherein A is a nitrogen comprising unit, phenyl, or substituted phenyl. Preferred nitrogen comprising A units include amino, pyrrolidino, piperidino,
15 morpholino, piperazino, and mixtures thereof.
Other suitable antioxidants are found as follows. A derivative of a-tocopherol, beta-tocopherol, gamma-tocopherol, delta-tocopherol, and alkyl esters of gallic 20 acid, especially octyl gallate and dodecyl gallate.
Another example of suitable antioxidants are the class of hindered amine light stabilisers (HALS), particularly those based 2,2,6,6-tetramethylpipiridines. 25
Preferred anti-oxidants are phenols, in particular 2,6-di-tert-butylphenol, 2,6-di-tert-butyl-4-methylphenol, and
- 5 -
mixtures of 2 and 3- tert-butyl-4-methoxyphenol. A preferred antioxidant is 4,4'-isopropylidenebis(2, 6-dimethylphenol) .
Mixtures of antioxidants may be use and in particular 5 mixtures that have synergic antioxidant.
The non-ionic surfactant may be, for example, fatty alcohol 10 polyethylene glycol ether or fatty alcohol ethoxylates,
alkylphenol ethoxylates, ethylene oxide and propylene oxide co-polymers, amine oxides, alkylamines, alkanolamines, polyglycerol esters, alkyl polyglucosides, and fatty acid N-alkylglucosamides. Preferred non-ionics are fatty alcohol 15 polyethylene glycol ether or fatty alcohol ethoxylates.
A preferred class of non-ionic surfactant is an alkyl chain in the range C1O to C18 linked to repeated ethoxylate groups; most preferred are alkyl chains having a chain length range C12 to C15. One will appreciate that the 20 melting point of the non-ionic is effected by both the chain length or nature of the chain length i.e., branching and number of ethoxylate/propyloxlate groups.
The greater the number of repeated ethoxylate groups the 25 greater the melting point of the non-ionic surfactant. A preferred non-ionic surfactant is a C1O to C18 alkyl chain distribution covalently bound to at least 40 EO; the link between the ethoxylate and the alkyl chain may either be an ester (fatty alcohol ethoxylates) or an ether linkage (fatty 3 0 alcohol polyethylene glycol ether).
- 6 -
The non-ionic surfactant has a melting point range that starts at 40 °C or above as measured by Differential Scanning Calorimetry (DSC). The DCS determines the start of the melting point by monitoring deviation from linearity of 5 the energy input during the heating process. Preferably the non-ionic surfactant has melting range that does not exceed 100 °C, more preferably 150 °C, most preferably 200 °C. The DSC protocol is given in the experimental section.
10 Non-ionic Lutensol™ named surfactants obtained from BASF and Non-ionic Genapol™ named surfactants obtained from Clariant having the requisite melting point were particularly suitable.
15 Other Aspects
Other adjuncts or carriers may be present in the granule. Preferred carriers are water soluble, e.g., sodium sulphate. Examples of adjuncts are perfumes, dyes, brightening agents, 20 enzymes etc. These may be incorporated by cogranulation. Adjuncts may be added to the non-ionic before or during granulation. The non-ionic may itself act as a binder which negates the need for further binder material.
25 The granule may itself be coated with, for example, sodium alginate, calcium cross linked alginate, wax and the like.
The granule may be also dusted with a fine powder to aid flow-for example zeolite, silica, clay, sodium sulphate.
- 7 -
Anti-oxidant/solid nonionic granules
5 1) 2,6-di-tert-butyl-4 methylphenol/50EONI Materials
90 gms of Genapol T 500 (Tallow 50EO nonionic) was heated to approximately 60 C and l0gms of 2,6-di-tert-butyl-4 methylphenol dissolved in the melt with mixing until a clear
10 solution obtained. The melt was poured and cooled rapidly to form a thin film of approximately 0.5 to 1 mm thickness on a plastic tray at 25 C. The resulting solid film was milled to the correct size fraction using a Moulinette mixer. The milled product was sieved to provide a powder sized between
15 180 and 1000 microns.
2) The same process an for 1) was applied to antioxidant
4,4'-isopropylidenebis(2,6-dimethylphenol) with the same
3) Granule, prepared by high shear mixer granulation,
containing 11.6% 2,6-di-tert-butyl-4 methylphenol, 54.3%
zeolite, 11.6% ascorbic acid and 22.5% PEG6000, where the
2,6-di-tert-butyl-4 methylphenol was added as a milled
4) Granule, prepared by high shear mixer granulation,
containing 12.7% 2,6-di-tert-butyl-4 methylphenol, 59.2%
sodium sulphate, 12.7% ascorbic acid and 15.4% PEG60Q0,
30 where the 2,6-di-tert-butyl-4 methylphenol was added as a milled powder.
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5} Granule, prepared by high shear mixer granulation, containing 12.0% 2,6-di-tert-butyl-4 methylphenol, 57.3% zeolite, 12.0 ascorbic acid and 18.7% Genapol T-500 (Clariant) , where the 2,6-di-tert-butyl-4 methylphenol was 5 added as a melt.
6) Granule, prepared by high shear mixer granulation, containing 12.6% 4,4'-isopropylidenebis(2,6-
dimethylphenol),84.9% sodium sulphate and 2.6% Sokalan CP13S 10 (BASF), where the 4, 4' -isopropylidenebis (2, 6-dimethylphenol) was added as a milled powder.
RATE OF RELEASE METHOD
15 4g of detergent powder (in this instance 0M0 MA) was
dissolved in 1 litre of demin. water at room temperature and stirred (magnetic stirrer) for 20 minutes in order for complete dissolution.
20 After the dissolution period, 0.lg of the antioxidant
containing granules, sieve fraction 180 to 1000 microns, were added to the solution with constant stirring.
A small sample of the solution was taken after 5 minutes 25 using a 2 ml syringe. This sample was immediately filtered through a Whatman Puradisc (1.0 micromol polyethersulfone membrane) filter. The filtered sample was analysed by HPLC to determine the percentage of antioxidant released.
- 9 -
The amount of anti-oxidant released into the wash solution after 5 minutes, for each of the examples, is shown in the following table.
Example % Anti-oxidant
Released after 5
Comparative 3 12
Comparative 4 12
Comparative 5 36
Comparative 6 28
MELTING POINT OF THE NON-IONIC SURFACTANTS
Melting point ranges of some commercial surfactants were 10 identified by heat cool cycling of a sample in the Perkin
Elmer™ DSC7 differential scanning calorimeter. Samples were
cooled to 0 °C then heated to 110 °C and cooled to 0 °C at a
rate of 10 °C per minute. This was repeated to confirm the
melting range. 15
The following table melting point ranges for some non-ionics
WO 2007/104412 PCT7EP2007/001557
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Non-ionic Surfactant DSC melting range/°C
Lutensol AT25 40 to 60
Lutensol AT50 47 to 65
Lutensol AT80 50 to 63
Lutensol AO3 0 30 to 58
Lutensol TO20 - to 32
Genapol T500 (50EO) 48 to 65
Genapol T800 (80EO) 50 to 68
The table shows that the AT series of surfactants have higher melting points than the AO series. This is due to 5 the AT series being prepared from a CI6 /C18 alcohol while the AO series are prepared from C13 /C15 alcohol. The TO sample uses a branched alcohol.
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1. A granule comprising:
(i) nonionic surfactant, the nonionic surfactant having
5 a starting melting point of 40 °c or above as
measured by differential scanning calorimetry; and, (ii) and an antioxidant, wherein the antioxidant is dissolved in the non-ionic surfactant.
10 2. A granule according to claim 1, wherein the weight ratio of antioxidant to non-ionic is in the range from 1:100 to 20:100.
3. A granule according to claim 2, wherein the weight ratio
15 of antioxidant to non-ionic is in the range from 3:100
4. A granule according to claim 3, wherein the weight ratio
of antioxidant to non-ionic is in the range from 5:100
20 to 15:100.
5. A granule according to any preceding claim, wherein the
antioxidant is selected from the group consisting of:
2, 6-di-tert-butylphenol, 2,6-di-tert-butyl-4-25 methylphenol, and
4,4 ' -isopropylidenebis (2, 6-dimethylphenol) .
6. A granule according to any preceding claim, wherein the
non-ionic is selected from is a C10 to C18 alkyl chain
3 0 covalently bound to at least 4 0 EO.
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7. A granule according to claim 1, wherein the antioxidant granules are a sieve fraction in the range 180 to 1400 microns.
5 8. A laundry detergent powder formulation comprising the
antioxidant granule, as defined in any preceding claim, in the range 0.1 to 5.0 wt %.
9. A method of preparing an antioxidant granule comprising
the steps of:
(i) melting a non-ionic surfactant the nonionic
surfactant having a starting melting point of 40°C or above as measured by differential scanning calorimetry;
(ii) dissolving an antioxidant in the melted non-ionic surfactant with mixing to form a antioxidant/non-ionic solution;
(iii) cooling the antioxidant/non-ionic solution to form a solid whilst forming a particulate matter.
|Indian Patent Application Number||1859/MUMNP/2008|
|PG Journal Number||24/2012|
|Date of Filing||28-Aug-2008|
|Name of Patentee||HINDUSTAN UNILEVER LIMITED|
|Applicant Address||HINDUSTAN UNILEVER LIMITED, UNILEVER HOUSE, B.D. SAWANT MARG, CHAKALA, ANDHERI EAST, MUMBAI -400 099|
|PCT International Classification Number||C11D11/00|
|PCT International Application Number||PCT/EP2007/001557|
|PCT International Filing date||2007-02-16|