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
  • C11D3/48—Medical, disinfecting agents, disinfecting, antibacterial, germicidal or antimicrobial compositions
• • 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
  • C11D3/3942—Inorganic per-compounds

Definitions

• This invention relates to a sanitising/destaining/ rinsing process and compositions, more particularly for use in rinsing in spray washing machines, such as dish and glass washers.
• the wash programme conventionally comprises an alkaline wash, followed by a final rinse in hot water containing a rinse additive. There may be additional pre-washes or pre-rinses to these two basic operations and they may be sub-divided.
• the wash temperature is 60-65°C and the rinse temperature is 80-85°C.
• wash and rinse temperatures were recommended by the National Sanitation Foundation in America in 1948/49 and the N.S.F. currently specify wash and rinsing conditions, including wash and rinse volumes, wash and rinse temperatures, wash and rinse pressures, together with minimum residence times in the rinse and wash processes for dish and glass washing machines.
• the recommendations on temperatures are based on the amount of heat required for thermal sanitisation. In America, the standards are often included in local regulations, but they have not per se been adopted outside North America. In many instances, the wash and rinse temperatures are alone specified in local regulations and the use of these temperatures has provided an acceptable level of sanitising.
• the sanitising action required once the temperatures have been reduced has been provided by the use of chlorine-release agents which are accepted as being capable of providing the necessary sanitising action.
• the use of available chlorine as a sanitiser in the final rinse water has, however several drawbacks.
• the first drawback is that if not carefully regulated the residual chloride can cause an increased level of corrosion.
• Other drawbacks include the residues left on glassware and the odour in use.
• a further disadvantage is that chlorine-release agents cannot easily be included in the rinse additive that must in any case be injected into the rinse line and, therefore, two products are required to be injected into the final rinse water.
• the concentration at which the quaternary compounds need to be used causes undesirable side effects in spray washing processes. These include generation of foam, poor rinsing effects, absorption onto the surfaces, followed by reaction with anionic materials, such as tannins, which causes staining, and reaction with food soils causing problems in the washing process.
• anionic materials such as tannins
• Iodine-based product cause problems due to the reaction thereof with starch, widely present in food soil, and the fact that iodine can vaporise when used at temperatures above 40-45°C.
• peroxy compounds have been recognized as bactericides for over a century they have never been widely used because of the slow rate of bacterial kill thereof and the high concentrations required. It was only following the production, or in situ generation, of peracid compounds, such as peracetic acid, that this type of chemical has become useful economically. However, it was quite unexpected that peroxy compounds would be effective at the low concentrations and short exposure times required for use in the rinsing sections of spray washing machines.
• the present invention provides a sanitising/ destaining/rinsing process for use in a spray washing machine characterised in that it comprises using a peroxy compound in rinse water.
• the rinse water also comprises a surfactant.
• the peroxy compound need not always be used with a surfactant.
• the peroxy compound preferably hydrogen peroxide
• the peroxy compound is generally used following one or more alkaline wash cycles.
• Sufficient peroxy compound may be used to provide up to 500 ppm available oxygen, preferably up to 50 ppm available oxygen, typically about 20 ppm available oxygen.
• the present invention also provides the use of a peroxy compound as a sanitising/destaining/rinsing agent in rinse water of a spray washing machine.
• the peroxy compound is used together with a surfactant- containing rinse aid following an alkaline wash.
• the present invention further provides an aqueous sanitising/destaining/rinsing composition characterised in that it comprises a peroxy compound and a surfactant suitable for use in a rinse aid.
• the peroxy compound will generally be used in the form of a combined composition which includes a surfactant together with the peroxy compound.
• Such compositions when added to the rinse water of spray washing machines may provide effective rinsing and drying properties, together with effective biocidal activity even when the machine is operated at reduced temperatures.
• the combination is preferably formulated as a liquid composition and the peroxy compound is preferably hydrogen peroxide.
• peroxy compounds may be used, although for practical reasons they should be in a liquid form, and to prevent subsequent problems on rinsing should not include high levels or inorganic salts.
• a stabiliser for the peroxy compound in the liquid composition will generally buffer the composition to a pH at which the peroxy compound is stable'(generally 2-to 5) and will also scavenge for metal ions which tend to destabilise the peroxy compound.
• Suitable stabilisers include organic and inorganic acids, alkali metal pyrophosphates and salts of tin alone or together with compounds of magnesium or phosphorus. Any stabiliser is generally used in a conventional amount.
• the peroxy compound is used in the combined composition together with a surfactant.
• Preferred surfactants are weakly foaming non-ionic wetting agents which are, for example, ethylene oxide adducts to fatty alcohols or alkyl phenols or ethylene oxide adducts to polypropylene oxides of molecular weight from 500 to 2000, commonly called the "PLURONICS", or adducts of ethylene oxide and propylene oxide with mono- or multifunctional initiators, commonly alcohols or amines as described in the book “Non-ionic Surfactants” by SCHICK (published by Marcel Dekker, 1966) or adducts of ethylene oxide, propylene oxide and/or butylene oxide with fatty alcohols or alkyl phenols.
• solubilisers which may be used in conventional amounts, include the low molecular weight alcohols typified by methanol, ethanol, isopropanol, propylene glycol, hexylene glycol and low molecular weight adducts of ethylene oxide and propylene oxide with mono- or multi- functional initiators, low molecular weight anionic compounds typified by the xylene, toluene and cumene sulphonates and low molecular weight alcohol phosphate esters or the phosphate esters of alcohol/ethylene oxide adducts.
• compositions according to the present invention may contain sufficient peroxy compound to provide up to 20% available oxygen, preferably from 1 to 10% available oxygen, typically about 5% available oxygen.
• the surfactant component may be present in amounts of up to 60% w/w, preferably from 10 to 50% w/w, typically about 20% w/w.
• compositions may be produced by conventional means involving mixing the components in an appropriate order.
• compositions are added to the rinse water of spray washing machines, thus providing in-use solutions.
• up to 500 ppm preferably about 20 ppm, available oxygen, would commonly be present.
• 500 ppm preferably about 75 ppm, surfactant would be provided.
• the machine was used to wash plates artificially soiled with the bacteria Micrococcus caseolyticus (NCIB 3251) in a starch-based soil and conditioned overnight. This ensured that the soil was not completely removed by the washing process.
• An unwashed control had a level of 10 5 to 10 6 bacteria.
• the washed plates were swabbed to measure residual bacteria and the log decimal reduction in the number of bacteria was calculated following each rinsing process.
• the following rinsing processes were used, the surfactant being Eth y lan CPG 660:-(1) Surfactant alone, at a concentration of 80 ppm, used at a wash temperature of 60°C and a rinse temperature of 80°C. These are the standard conditions referred to above and it is to be assumed that they provide adequate sanitising.
• a value of at least 4 is desirable.
• composition according to the present invention was evaluated:
• This composition was evaluated at an in-use concentration of 400 ppm, generating 30 ppm AvO 2 , and its ability for rinsing, drying and sanitising measured and compared to a conventional system using the machine and wash programme detailed in Example 1.
• compositions according to the present invention are provided.

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• Chemical & Material Sciences (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)
• Inorganic Chemistry (AREA)
• Detergent Compositions (AREA)

Applications Claiming Priority (2)

Publications (2)

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ID=10576042

Family Applications (1)

Country Status (5)

Cited By (27)

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Family Cites Families (10)

• 1985
  • 1985-03-15 GB GB858506735A patent/GB8506735D0/en active Pending
• 1986
  • 1986-03-13 AU AU54699/86A patent/AU5469986A/en not_active Abandoned
  • 1986-03-14 EP EP86301874A patent/EP0195619A3/de not_active Withdrawn
  • 1986-03-14 DK DK118686A patent/DK118686A/da not_active Application Discontinuation
  • 1986-03-14 ES ES553053A patent/ES8800339A1/es not_active Expired

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