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
  • C11D3/16—Organic compounds
  • C11D3/38—Products with no well-defined composition, e.g. natural products
  • C11D3/386—Preparations containing enzymes, e.g. protease or amylase
  • C11D3/38609—Protease or amylase in solid compositions only
• • 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
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/04—Water-soluble compounds
  • C11D3/06—Phosphates, including polyphosphates
• • 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
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/04—Water-soluble compounds
  • C11D3/08—Silicates
• • 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
  • C11D3/02—Inorganic compounds ; Elemental compounds
  • C11D3/04—Water-soluble compounds
  • C11D3/10—Carbonates ; Bicarbonates

Definitions

• This invention relates to dishwashing compositions and particularly to compositions in the form of a powder suitable for use in automatic dishwashing machines.
• Detergent compositions for automatic dishwashing machines which comprise a bleaching agent, usually a chlorine-containing bleaching agent, and which are highly alkaline compositions having a solution pH above ll.5.
• a bleaching agent usually a chlorine-containing bleaching agent
• highly alkaline compositions having a solution pH above ll.5.
• These conventional highly alkaline compositions are efficient in cleaning dishes but suffer from a number of disadvantages, notably that they are corrosive towards some metal components, ceramic glazes and pigments.
• Compositions containing a chlorine bleach have the further disadvantages of odour problems and that due to instability of the bleach they may be difficult to perfume and/or dye and have a limited shelf-life.
• a detergent composition free from a chlorine bleach and purporting to obviate the disadvantages of conventional dishwashing compositions is proposed in European Patent Application No l35227 A2.
• This composition is based on a peroxy compound bleach used in combination with an amylolytic enzyme, is mildly alkaline with a solution pH of about 9.3 to about l0.8 and can be presented in the form of a particulate product thereby obviating the disadvantages of using a liquid composition.
• This composition overcomes many of the disadvantages of the conventional highly alkaline compositions containing a chlorine bleach but still has the disadvantage that it contains a bleaching agent.
• the present invention is concerned with a bleach-free dishwashing composition which is only mildly alkaline but is at least as effective in cleaning dishes as compositions proposed hitherto.
• the composition is presented in powder form and exhibits a solution pH under dishwashing conditions in an automatic dishwashing machine of below ll.0 and preferably no greater than about l0.0.
• a detergent powder composition for use in automatic dishwashing machines comprising -
• the composition is mildly alkaline and in particular has a solution pH of about l0.0, this being the pH of a solution of 3 g/litre of the composition in water.
• the alkalinity or solution pH of the composition which should generally be maintained above about 9 in order that the enzymes be effective, is largely established and maintained by components (a), (b) and (c) which exhibit a builder/buffer effect on the solution and are used in sufficient amounts to provide the desired solution pH.
• the combined weight of builder and buffering agents, components (a), (b) and (c) should be at least 50% of the composition and may be up to 90% or even higher of the composition. Usually, however, the composition will contain an appreciable amount of one or more bulking agents so that the combined weight of components (a), (b) and (c) will be no more than about 70% of the composition.
• the composition will usually contain one or more bulking agents in an amount of from 30% to 60% by weight. Any bulking agent may be used which does not appreciably inhibit the effectiveness of the enzymes or adversely modify the alkalinity of the composition.
• Sodium sulphate is a typical and preferred bulking agent and sodium chloride may also be used.
• Our preferred compositions contain both sodium sulphate and sodium chloride in a ratio of about l:0.5 by weight.
• the preferred phosphate, component (c), is sodium tripolyphosphate.
• the composition may contain a low-foaming surfactant and advantageously does contain a small amount, for example up to 5% by weight, of such a component. However we have found that if present, only very small amounts of surfactant are required and in particular amounts below 0.5% by weight.
• Any low-­foaming surfactant may be employed but will usually be a non-ionic surfactant such as an alkylene oxide condensate in which the alkoxy moity is derived from ethylene oxide or propylene oxide or a mixture thereof.
• suitable surfactants are the well-known ethoxylated straight-chain alcohols.
• the surface active agent is biodegradable.
• the composition contains both an amylolytic enzyme and a proteolytic enzyme.
• at least one of the enzymes and especially preferably both of the enzymes are in granular form.
• the enzymes are used in mixtures in which the ratio by weight of amylolytic enzyme: proteolytic enzyme is from l:4 to 4:l and usually from l:2 to 2:l.
• amylolytic enzyme and any proteolytic enzyme may be used which at pHl0 exhibits at least 50% and preferably at least 60% of its maximum activity.
• the enzyme mixture is present in the composition in an amount such that the composition has an amylolytic activity of at least l50 KNU (Kilo Novo units), preferably at least 300 KNU, per kilogram and a proteolytic activity of at least 6 Anson units per kilogram.
• Amylolytic activity in KNU is determined as described in United States Patent Specification No 3,93l,034.
• Proteolytic activity in Anson units is determined as the amount of enzyme which degrades haemaglobin under standard conditions as described in Journal of General Physiology, Vol 22 (l938), page 79.
• compositions of the invention may if desired contain other ingredients known for use in automatic dishwasher compositions, for example sequestering agents, soil-suspending agents, corrosion inhibitors, drainage-promoting agents, crystal modifiers, dyes and perfumes.
• compositions of the invention are presented as powders which can be produced by dry-mixing the powdered/granular materials and spraying any liquid components, e.g. a surfactant, on to the mixture during mixing.
• liquid components e.g. a surfactant
• compositions Five powder dishwashing compositions were prepared to the following formulations in which the ingredients are expressed as percentages by weight of the compositions:-
• the sodium tripolyphosphate was stirred in a Kenwood food mixer and the surfactant (liquid) was added, followed by the other liquid ingredients. When all the liquids had been absorbed, the remaining ingredients were added to and mixed in the composition.
• the dirty plates being cleaned were soiled by coating them with both a greasy soil and a protein soil and baking them at l50°C in an oven. Some plates were baked for 5 minutes, some for 7.5 minutes and others for l0 minutes.
• the greasy soil was a mixture of peanut butter (5), butter (2), lard (2.5) and a mineral oil (2), the figures indicating parts by weight.
• the protein soil was a mixture of raw egg (5) peanut butter (l), lard (l), butter (l) and milk (l), the figures being parts by weight.
• the dry plates were removed and assessed for cleanliness.
• the plates were coated with a thin film of activated charcoal and their reflectance was then determined at several points on the surface using a Bosch Light Reflectance meter.
• the amount of activated charcoal adhering to the surface corresponds to the amount of soil remaining on the plate, being greater the greater the amount of soil.
• a numerical assessment was derived of the cleanliness of the plates and hence of the cleaning ability of the dishwashing composition. As a blank against which cleanliness was assessed there was taken a new, unsoiled plate which was washed in the machine and assessed for cleanliness as above.

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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 (1)

Family

ID=10602228

Family Applications (1)

Country Status (3)

Cited By (7)

Citations (5)

• 1986
  • 1986-08-05 GB GB868619045A patent/GB8619045D0/en active Pending
• 1987
  • 1987-07-20 GB GB878717084A patent/GB8717084D0/en active Pending
  • 1987-07-20 EP EP87306403A patent/EP0256679A1/de not_active Withdrawn
  • 1987-07-29 AU AU76251/87A patent/AU7625187A/en not_active Abandoned

Patent Citations (5)

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