Classifications

• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L15/00—Washing or rinsing machines for crockery or tableware
  • A47L15/42—Details
  • A47L15/44—Devices for adding cleaning agents; Devices for dispensing cleaning agents, rinsing aids or deodorants
• • A—HUMAN NECESSITIES
  • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
  • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
  • A47L15/00—Washing or rinsing machines for crockery or tableware
  • A47L15/0018—Controlling processes, i.e. processes to control the operation of the machine characterised by the purpose or target of the control
  • A47L15/0055—Metering or indication of used products, e.g. type or quantity of detergent, rinse aid or salt; for measuring or controlling the product concentration
• • 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
  • C11D7/06—Hydroxides
• • 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
  • C11D7/22—Organic compounds
  • C11D7/26—Organic compounds containing oxygen
  • C11D7/265—Carboxylic acids or salts thereof
• • 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
  • C11D7/22—Organic compounds
  • C11D7/32—Organic compounds containing nitrogen
  • C11D7/3245—Aminoacids
• • 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
  • C11D7/22—Organic compounds
  • C11D7/36—Organic compounds containing phosphorus
• • 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
  • C11D2111/00—Cleaning compositions characterised by the objects to be cleaned; Cleaning compositions characterised by non-standard cleaning or washing processes
  • C11D2111/40—Specific cleaning or washing processes
  • C11D2111/44—Multi-step processes

Definitions

• cleaners are also intended to prevent the formation of deposits (e.g. tannins or lime) due to incomplete cleaning of the dishes or to remove deposits that have already formed.
• DE-A 37 07 366 discloses a method for machine dishwashing, in which the dishes are subjected to pre-cleaning by spraying on a cleaning solution which is washed off again by the washing liquor after a predetermined exposure time in a main cleaning area.
• the pre-cleaner solution is prepared from a pre-made pre-cleaner by dilution.
• the pre-cleaner contains an alkali component and a complexing agent for water softening.
• DE-A 43 39 503 describes this procedure as disadvantageous because a mixture of alkali component and complexing agent is difficult to rinse off from the dishes and since the complexing agent, as a water softener, only develops its full effectiveness in the main cleaning area.
• This prior art therefore teaches that the pre-cleaner solution to be sprayed on should not contain any complexing agents, but only an alkali component.
• the complexing agent is metered into the wash liquor separately and is not sprayed onto the dishes.
• the present invention has for its object to provide a method for cleaning dishes of the type mentioned, which has a good cleaning effect with economical consumption of cleaning agents, especially the expensive complexing agent.
• pre-cleaner solution denotes the solution that is actually brought into contact with the dishes by spraying on and is obtained by diluting the components of the pre-cleaner with water. These components or components of the precleaner will generally be concentrates.
• pre-cleaning denotes a process upstream of the main cleaning, which does not necessarily have to be the first process step.
• further pre-cleaning steps which are not defined in claim 1, can also be carried out upstream.
• a first pre-cleaning step (pre-rinsing) for removing coarse impurities can be provided.
• spraying means bringing the pre-cleaner solution into contact with the dishes in such a way that the pre-cleaner solution at least largely wets them. It is preferably a finely divided spraying.
• the term "separate metering into the pre-cleaning solution” means that the pre-cleaning solution consists of at least the two components alkali component and complexing agent is produced by mixing. It is preferably diluted with water. This mixing preferably takes place immediately before spraying onto the dishes.
• the separate metering can be done by metered addition of the components in a premix tank, the premix tank then feeds the spray nozzle or the spray nozzles.
• the pre-cleaner components can also be metered directly into the water jet that feeds the spray nozzles using a metering pump.
• the different components of the pre-cleaner solution to be sprayed on from separate spray nozzles and only to form the pre-cleaner solution directly in situ on the dishes.
• main cleaning denotes a process following the pre-cleaning in which the dishes are showered and / or washed around by a washing liquor. Only the pre-cleaning solution sprayed on in the pre-cleaning step and diluted accordingly by the washing liquor can be used as the cleaner in this wash liquor. However, other detergents can also be added to the wash liquor, which contain the usual components such as surfactants, enzymes, disinfectants, and usual additives and auxiliary substances such as solubilizers, defoamers, fragrances, dyes, thickeners, preservatives and hardness dispersants.
• solubilizers solubilizers, defoamers, fragrances, dyes, thickeners, preservatives and hardness dispersants.
• step 1 includes all cleaning and / or rinsing steps following the main cleaning according to the invention.
• step 2 the main cleaning is followed by a further main cleaning step with another cleaner.
• step b the main cleaning mentioned in step 1) as step b) is immediately followed by a final rinse (usually with a customary rinse aid) and possibly also by a (further) rinse with water. All of these variants are included in the term "rinsing" used in claim 1.
• An alkali component is a substance which has an alkaline reaction in aqueous solution.
• Alkali metal hydroxides especially sodium and / or potassium hydroxide, are preferred as the alkali component.
• everyone is a complexing agent in the sense of the invention Substance that can hold the metal ions (especially alkaline earth ions) that make up the hardness of the water in solution by complex formation.
• the invention is based on the surprising finding that the individual, needs-based metering of alkali component on the one hand and complexing agent on the other hand into the pre-cleaning solution to be sprayed on enables an improved cleaning effect compared to the process of DE-A 43 39 503 with simultaneous economical use of detergent (in particular complexing agent).
• the invention has recognized that, in contrast to the technical teaching of the cited document, the complexing agents do not develop their full effectiveness only in the washing cycle, but surprisingly, as a component of the sprayed-on pre-cleaner solution, significantly improve the cleaning effect.
• the alkali component preferably contains 5-50%, more preferably 10-40% total alkalinity calculated as NaOH. Unless otherwise stated, all percentages are percentages by weight. The total alkalinity is calculated in each case as NaOH. If, for example, the alkalinity is added as potassium hydroxide, its weight fraction must be converted into NaOH weight fraction based on the molecular weight ratios of NaOH and KOH. Potassium hydroxide is preferred as the alkali component, since it has been shown that cleaning agents containing potassium salt have an improved cleaning action compared to cleaning agents containing sodium salt and are easier to rinse out are. There is no plausible explanation for this empirical finding. To the extent that other detergent components are added as alkali metal salts, the use of potassium salts is preferred for the same reason. However, it should be noted that the use of, for example, sodium salts is readily possible within the scope of the invention.
• the alkali component is particularly preferably a relatively high-dose aqueous solution with a total alkalinity in the range 30-50%.
• a pre-cleaner solution with a relatively high proportion of alkali can be sprayed onto the dishes.
• surfactant component denotes any surfactant-containing substances.
• surfactants are all substances which can reduce the interfacial tension of an aqueous solution.
• Anionic, cationic, nonionic and amphoteric surfactants can be used.
• Surfactants that can be used are in Römpps Chemielexikon, 9th ed., Vol. 6, p.
• Nonionic or amphoteric surfactants can preferably be used, for example surfactants from the class of the fatty alkoxylates and the N-alkylaminocarboxylates.
• the disodium salt or dipotassium salt of capryliminodipropionic acid may be mentioned by way of example.
• the surfactant additive sets the surface tension of the pre-cleaner solution and improves and accelerates cleaning through faster infiltration and detachment of dirt deposits and through emulsification in the wash liquor during the subsequent main cleaning.
• the surfactant additive can in particular improve the cleaning of rough surfaces (for example used plastic dishes), since the ability of the pre-cleaner solution to penetrate the roughened plastic surface is improved.
• An oxidation component in the sense of the invention is any component that has an oxidizing effect on at least parts of the soiling of the dishes.
• active chlorine-containing compounds such as Chlorites, hypochlorites and active oxygen-containing compounds such as hydrogen peroxide solutions, peracids or their salts are called.
• the alkali component and / or the complexing agent can also contain further constituents.
• examples include phosphonic acids or their salts, which can be part of the alkali component, for example, and are accordingly metered in together with the precleaner solution during the preparation.
• Phosphonic acids that can be used are, for example, phosphonobutane tricarboxylic acid; Aminotrismethylenephosphonic acid, its homologs based on ethylenediamine, diethylenetriamine or hexamethylenediamine; Hydroxyethane diphosphonic acid.
• the use of phosphonobutane tricarboxylic acid or its potassium salt is preferred.
• the total alkalinity of the sprayed pre-cleaner solution is 0.5-3%.
• the proportion of complexing agents in the sprayed-on pre-cleaner solution is preferably 0.05-5%, more preferably 0.05-3%, further preferably 0.1-2%.
• main cleaner The addition of a separate main cleaner is generally not necessary for main cleaning, since the pre-cleaner components rinsed off the dishes during main cleaning dissolve in the wash liquor and have a sufficient cleaning action.
• the complexing agent added separately according to the invention ensures during main cleaning that residual hardness present in the wash liquor is complexed and does not form any undesirable deposits or deposits.
• nitrilotriacetic acid sodium salt 40 parts by weight of nitrilotriacetic acid sodium salt are dissolved in 60 parts by weight of water.
• a conveyor belt dishwasher with three Stierlen-BTM type 5000 tanks was used to carry out the cleaning process.
• the machine was fed with softened Hamburg city water (residual hardness ⁇ 1 ° dH).
• the machine's fill water quantity was 300 l
• the rinse water quantity was 600 l / h.
• a spray system for spraying the pre-cleaning solution was installed, which was operated at a throughput of 20 l / h.
• the dwell times of the dishes in the pre-rinse or pre-clearing area still in front of the spray system were 10 s, in the spray area 5 s, in the subsequent main cleaning area 1 - 1.5 min.
• the temperatures in the area of pre-clearing were 45 to 50 ° C, in the two main cleaning tanks 50 to 55 (first tank) and 55 to 60 ° C (second tank), the temperature in the rinse tank was 75 - 85 ° C.
• the 300 l volume of fill water filled before starting up the machine was mixed with 96 g of complexing agent component (0.23 g / l) and 450 g of alkali component (1.5 g / l).
• test soiling from tea tannins on coffee or tea utensils could be completely removed with the specified parameters.
• the complexing agent component was metered directly into the first main cleaning tank and not, as provided according to the invention, into the precleaner solution.
• This procedure corresponds to the technical teaching of the prior art according to DE-A-43 39 503.
• the consumption of alkali component was thus 20% higher, the concentration of the alkali component in the wash liquor had to be increased from 1.5 g / l to 1.8 g / l.

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)
• Health & Medical Sciences (AREA)
• Emergency Medicine (AREA)
• Detergent Compositions (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=7795284

Family Applications (1)

Country Status (3)

Cited By (13)

Families Citing this family (3)

Citations (5)

• 1996
  • 1996-05-24 DE DE19621053A patent/DE19621053A1/de not_active Ceased
• 1997
  • 1997-03-07 DE DE59704924T patent/DE59704924D1/de not_active Revoked
  • 1997-03-07 AT AT97103898T patent/ATE207107T1/de not_active IP Right Cessation
  • 1997-03-07 EP EP97103898A patent/EP0808894B1/fr not_active Revoked

Patent Citations (5)

Also Published As

Similar Documents

Legal Events