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
  • C11D3/0005—Other compounding ingredients characterised by their effect
  • C11D3/0073—Anticorrosion 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
  • C11D3/02—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
  • C11D7/00—Compositions of detergents based essentially on non-surface-active compounds
  • C11D7/02—Inorganic compounds
  • C11D7/04—Water-soluble compounds
  • C11D7/10—Salts
  • C11D7/14—Silicates

Definitions

• the present invention relates to the use of cogranules based on alkali metal carbonate and on alkali metal silicate, as alkaline agents reducing visible corrosion of glass and decorations of glass or porcelain, in detergent compositions in particular for washing in the dishwasher.
• Alkali metal silicates in particular sodium silicates, are widely used in detergent compositions for dishwashers. They provide a buffering effect, detergent power and dispersing action in the detergent bath.
• Metasilicates (SiO 2 / M 2 O ratio equal to 1 where M represents an alkali metal) have been particularly used in detergents for dishwashers because of their high detergent power.
• these high alkalinity products had the disadvantage of deteriorating the surface of the glass and degrading the decorations of glass or porcelain. It thus appeared, after a number of washes with these detergents, a frosted glass, colored iridescence, white streaks or a continuous whitish veil on the glass, as well as a deterioration of the decorations. They have been gradually replaced by disilicates (SiO 2 / M 2 O ratio equal to 2) which have the advantages of the alkaline metasilicates listed above. However, even if these disilicates have a lower alkalinity than metasilicates, they still do not sufficiently protect the glass and the decorations against corrosion.
• the silicates have been replaced by sodium tripolyphosphates, which perform functions equivalent to those of the silicates and which protect the glass against temporary deposits, particularly deposits of calcium carbonate.
• tripolyphosphates also have the disadvantage of causing corrosion of the glass and the decorations. Indeed, due to their complexing power of calcium, they contribute to the surface rupture of the glass network by passage of the calcium in solution, which accelerates the corrosion of the glass; similarly, their complexing or sequestering power of heavy metals leads to the degradation of glass and porcelain decorations.
• tripolyphosphates are used less and less in detergents due to environmental standards.
• the subject of the invention is the use, as alkaline agents reducing visible corrosion of glass and glass or porcelain decorations, in detergent compositions in particular for washing in the dishwasher, of co-granules comprising an alkali metal carbonate and an alkali metal silicate of formula nSiO 2 , M 2 O, formula in which M represents an alkali metal and n is of the order of 1.6 to 3.5, preferably of the order of 1.6 to 2,4, said co-granules having a weight ratio, expressed in dry terms, carbonate / silicate of the order of 45/55 to 80/20, preferably of the order of 60/40 to 75/25, with a weight ratio water / silicate expressed as dry at least about 33/100, preferably of the order of 40/100 to 120/100.
• cogranules which can be used, there may be mentioned in particular those forming the subject of European patent applications EP-A-488,868 and EP-A-561,656 and meeting the definition above. They are obtained by adsorption and / or absorption of an aqueous solution of hydrated alkali metal silicate, on a particulate support chemically inert with respect to the silicate, consisting of an alkali metal carbonate.
• the amount of mineral support brought into contact with the silicate solution is adjusted so that the water / silicate weight ratio expressed as dry is at least 33/100.
• the upper limit of this ratio corresponds to the limits for which we keeps a silicate in powder form with fluid flow ("free flowing"), that is to say usable in detergency. This is advantageously less than or equal to about 120/100.
• the preparation of the cogranules can be done by any available means of bringing the silicate solution into contact with the carbonate particles.
• the cogranules are subjected to a densification operation.
• alkali metal silicates and carbonates there may be mentioned in particular those of sodium and potassium, and very particularly those of sodium.
• cogranules based on silicate and carbonate as described above mention may be made of Nabion® manufactured and marketed by Rhône-Poulenc.
• Said cogranules can be used, as alkaline agents reducing visible corrosion of the glass, in amounts such that they represent around 3 to 90%, preferably around 3 to 70% by weight of the said said compositions.
• Table 1 shows that the use of NABION® as an alkaline agent results in a lesser loss in mass of the glass slides, as well as in a homogeneous iridescence of the surface of the glass slides, against a greater and heterogeneous iridescence, with the presence of 4 different colors when using a mixture of carbonate and silicate or silicate alone.
• Table 3 shows that the use of NABION® as an alkaline agent reduces the visible corrosion of glass and glass decorations, for all the glasses tested, by comparison with a mixture of carbonate and silicate.
• NABION® as an alkaline agent reduces the visible corrosion of plate decorations, for all the types of plates tested, by comparison with a mixture of carbonate and silicate.
• NABION® such as 30* atomized silicate (expressed in dry) 8.6 liquid silicate R2 (expressed as dry) 8.6 light carbonate (expressed in dry) 16.39 0 sequestering agent based on sodium citrate dihydrate 17 17 17 dispersant based on sodium polyacrylate 6 6 6 non-ionic surfactants 2 2 2 bleaching system (perborate, 1H 2 O + TAED **) 11 11 11 enzyme 2 2 2 sodium sulfate 30 30 30 30 water (qs 100) 2 7.01 23.4 initial pH 10.57 10.6 10.18 final pH 10.48 10.39 9.9 mass loss (% x1000) 305.4 363.9 519.8 iridescence nature homogeneous heterogeneous heterogeneous number of different colors 1 4 4 * corresponding to 8.6 parts of silicate (expressed

Landscapes

• 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=9480383

Family Applications (1)

Country Status (2)

Cited By (1)

Citations (7)

• 1995
  • 1995-06-26 FR FR9507634A patent/FR2735787B1/fr not_active Expired - Fee Related
• 1996
  • 1996-06-24 EP EP96401384A patent/EP0751212A1/de not_active Withdrawn

Patent Citations (7)

Also Published As

Similar Documents

Legal Events