Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/39—Organic or inorganic per-compounds
  • C11D3/3902—Organic or inorganic per-compounds combined with specific additives
  • C11D3/3937—Stabilising agents
  • C11D3/394—Organic compounds
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/39—Organic or inorganic per-compounds
  • C11D3/3902—Organic or inorganic per-compounds combined with specific additives
  • C11D3/3937—Stabilising agents
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D3/00—Other compounding ingredients of detergent compositions covered in group C11D1/00
  • C11D3/39—Organic or inorganic per-compounds
  • C11D3/3945—Organic per-compounds

Definitions

• This invention is concerned with organic peroxyacids and their manufacture.
• the invention is particularly con ⁇ cerned with the stability of said organic peroxyacids.
• Organic peroxyacids are able to function as bleaching agents in a detergent composition.
• Organic peroxyacids which have been proposed for such use include peroxybenzoic acid, peroxyphthalic acid, isomers and substituted derivatives thereof, peroxyalkanoic acids and diperoxyalkanedioic acids such as diperoxyazelaic acid and diperoxydodecanedioic acid. Discussion of such acids can be found in US Patents 4,100,095, 4,170,453 and 4,325,828 as well as numerous other documents.
• Another series of acids which have been proposed are phthalimido substituted peroxyalkanoic acids disclosed in EP-A-325288.
• WO 90/07501 (Interox) describes the variation in stability of peroxyacids according to features of their structure. This document teaches that phthalimido peroxyacetic acid is somewhat explosive whereas longer chain ho ologues are relatively more stable.
• transition metal ions can catalyse unwanted decomposition of peroxyacid compounds and it has, therefore, been proposed to mix peroxyacid com- pounds with chelating agents to enhance storage stability of organic peroxyacid-containing compositions and/or stabilise the wash liquor against unwanted decomposition of the peroxyacid.
• chelating agents are disclosed in US Patents 4,170,453 and 4,100,095. This disclosure is also reviewed in EP-349220.
• organic peroxyacids may be incorporated into compositions which contain only a minority proportion of peroxyacid and which also contain a chelating agent for sequestering transition metal ions, this chelating agent being incorporated for the purpose of promoting storage stability of the peroxyacid and/or stability of the peroxyacid in a wash liquor during use.
• a chelating agent for sequestering transition metal ions such as sodium citrate
• European published application 349220 is concerned with amidoperoxyacids which contain an amide link in a hydrocar ⁇ bon chain.
• This Patent teaches that the storage stability of these peracids can be improved considerably by washing the peracids with phosphate buffer and leaving some phosphate in contact with the peracid after washing.
• the amidoperoxyacids are acid sensitive and this beneficial effect of phosphate buffer is prin ⁇ cipally attributed to neutralisation of residual strong acid left from the reaction in which the amido peroxyacid is prepared.
• the phosphates which are used may be or- thophosphates or pyrophosphates or a mixture of the two. Such phosphates have the ability to sequester transition metal ions.
• the present invention provides the use of a binding agent for transition metal ions to enhance stability of a substantially water-in ⁇ soluble organic peroxyacid against exothermic decomposition initiated by heat.
• DSC differential scanning calorimetry
• bringing an organic peroxyacid into contact with a binding agent in accordance with this invention leads to a composition in which the temperature of thermal decomposition has increased.
• the decomposition may also occur over a temperature range of different width.
• differential scanning calorimetry may show an increase in the temperature at which maximum decomposition occurs and/or an increase in the temperature at which decomposition begins. The outcome of a DSC measurement will show these results as a shift in the position of a peak, or as a shift in the base of the peak at its lower temperature side, respec ⁇ tively.
• a preferred possibility is to precipitate the organic peroxyacid in the presence of the binding agent, such that 0.3-3% by weight, preferably 1-2% by weight, more preferably 1-1.5% by weight of the binding agent, as cal ⁇ culated on the total weight of peroxyacid and binding agent, remains in contact with the peroxy acid.
• the final pH of the thus-obtained material is in the range of from 3.5-6, preferably from 4-5. This leads to a beneficial enhancement of stability, and moreover it is then possible to -wash the peroxyacid further without losing the enhanced stability.
• a composition obtained in this way is more robust than compositions obtained in other ways.
• Binding agents for transition metals which are suitable for the present invention include dihydrogen orthophosphate, pyrophosphate, polyacrylate, titanium chloride, stannic salts, and stannous salts.
• the effectiveness and hence the suitability of a binding agent can be assessed by differen ⁇ tial scanning calorimetry as mentioned further below.
• the preferred binding agent is dihydrogen orthophosphate.
• Peroxyacids which are particularly envisaged include phthalimido-substituted peroxyalkanoic acids of formula
• peroxyacids are the diperoxy alkane dioic acids of formula HO 3 C-R-CO 3 H and peroxyalkanoic acids of formula
• reaction medium comprises a mineral acid, such as sulphuric acid
• all or part of it can be premixed with the hydrogen peroxide to form an equilibrium mixture containing for example permonosulphuric acid that can itself perform the peroxidation reaction.
• premixing separates the exothermic dilution/reaction between hydrogen peroxide and sulphuric acid from the peroxidation reaction.
• DSC differential scanning calorimetry
• the mixture was cooled to below 5°C in a water/ice bath.
• aqueous hydrogen peroxide approximately 80% w/w was added with continuous stirring into the reaction mixture progressively during a period of about 5 to 10 minutes while keeping the temperature below 5°C, until a total amount of 3.5 moles per mole of carboxylic acid has been introduced, i.e. a 2.5 molar excess compared with the stoichiometric amount.
• the reaction mixture was then stirred for a further 50 minutes.
• reaction mixture was poured into a stirred, ice cold solution consisting of 30 grams disodium hydrogen orthophosphate dissolved in 750 grams demineralised water. Before addition this solution was at approximately pH 8.0 and at the end of the addition the pH had dropped to between pH 4.0 and pH 4.5.
• phthalimido-6-peroxyhexanoic acid was investigated by DSC. The resulting print-out is reproduced as Fig. 5. This sample contained about 5% of the corresponding phthalimido hexanoic acid. It can be seen that this sample showed endothermic melting between about 80 and 90°C followed by exothermic decomposition reaching a maximum at about 125°C.

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• Chemical & Material Sciences (AREA)
• Inorganic Chemistry (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Detergent Compositions (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)

Priority Applications (5)

Applications Claiming Priority (2)

Publications (1)

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Family Applications (1)

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Cited By (3)

Families Citing this family (1)

Citations (6)

• 1993
  • 1993-03-05 GB GB939304513A patent/GB9304513D0/en active Pending
• 1994
  • 1994-02-17 CA CA002156170A patent/CA2156170A1/en not_active Abandoned
  • 1994-02-17 DE DE69401499T patent/DE69401499T2/de not_active Revoked
  • 1994-02-17 BR BR9405941A patent/BR9405941A/pt not_active IP Right Cessation
  • 1994-02-17 AU AU61416/94A patent/AU6141694A/en not_active Abandoned
  • 1994-02-17 EP EP94908344A patent/EP0687293B1/en not_active Revoked
  • 1994-02-17 ES ES94908344T patent/ES2097642T3/es not_active Expired - Lifetime
  • 1994-02-17 JP JP6519512A patent/JPH08507761A/ja active Pending
  • 1994-02-17 WO PCT/EP1994/000465 patent/WO1994020600A1/en not_active Application Discontinuation
  • 1994-02-24 ZA ZA941270A patent/ZA941270B/xx unknown

Patent Citations (6)

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