EP0706557A1

EP0706557A1 - Dishwasher agent with biodegradable builders

Info

Publication number: EP0706557A1
Application number: EP94918883A
Authority: EP
Inventors: Willi Buchmeier; Hans Andree; Peter Krings; Birgit Burg; Jürgen Härer; Peter Jeschke
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1993-06-28
Filing date: 1994-06-20
Publication date: 1996-04-17
Also published as: WO1995000623A1; HUT73202A; DE4321430A1; CZ342395A3; CA2166186A1; HU9503693D0; PL312472A1

Abstract

The invention concerns low-alkaline agents for use in dishwashing machines, the agents containing builders which are readily biodegradable. These readily biodegradable builders are copolymers of [meth]acrylic acid or [meth]acrylate, maleic acid or maleate and vinyl alcohol and/or vinyl acetate.

Description

Dishwashing liquid with biodegradable bullder component

The invention relates to alkaline dishwashing detergents for the mechanical cleaning of dishes with a biodegradable bath component.

The latest generation of low-alkaline agents for the mechanical cleaning of dishes contain, in addition to bleaching agents based on oxygen, surface-active substances and enzymes, a combination of water-soluble builders which are derived from complexing agents, e.g. Citrate, from alkali carriers, e.g. Soda, bicarbonate or disilicate, and from dispersants such as e.g. Polycarboxylates exist. Other possible binder components are organophosphonic acids, aminocarboxylic acids or crystalline layered silicates; on the phosphates previously used, e.g. Pentasodium tripolyphosphate is largely dispensed with today for ecological reasons.

The polycarboxylates used in today's dishwashing detergents, e.g. Maleinat / Acrylat-Copoly ere, prevent limescale deposits when the residual water hardness is too high in the cleaning and rinse cycle; with a high salt load in the washing liquor, they also improve the rinse aid effect.

However, a disadvantage of this type of polycarboxylates is that they are difficult to biodegrade. There is therefore a need for machine dishwashing detergents which contain biodegradable builder components but at the same time the usual range of services from show modern dishwashing detergents. Many biodegradable builder components such as oxidized starch or polyaspartic acid are good dispersants for failed calcium carbonate, but poor complexing agents for water hardness.

US Pat. No. 3,887,480 discloses dishwashing and textile cleaning agents which contain a polymer which consists of 35-70 mol% maleic acid, 20-45 mol% vinyl acetate and 2-40 mol% acrylic acid. The European patent EP 0 193 360 B1 describes zeolite-containing textile detergents, the polycarboxylate poly ere composed of a C3-Cio-onocarboxylic acid, a C ^ -Cß-dicarboxylic acid and a nonionic spacer, for. B. vinyl alcohol included. The US Pat. No. 3,755,264 discloses copolymers which, for. B. from 85 to 99 mol% of maleic anhydride and 1 to 15 mol% of a mixture of acrylic acid and vinyl acetate. The European patent application EP 0 076 992 AI discloses u. a. the use of polymers composed of 50-95% by weight of acrylic acid, 0.5 to 5% by weight of vinyl acetate and up to 49% by weight of maleic acid as incrustation inhibitors in washing and cleaning agents.

Surprisingly, it has now been found that copolymers, which in certain, can be found in the abovementioned. The quantitative ratios not described in (meth) acrylic acid or (meth) acrylate, maleic acid or maleate and vinyl alcohol and / or vinyl acetate are outstandingly suitable as builder components in automatic dishwashing detergents.

The invention relates to a low-alkaline agent for machine cleaning of dishes, the 1% by weight aqueous solution of which has a pH of 8 to 11.5, preferably 9 to 10.5, containing water-soluble builder components and bleaching agents based on oxygen, characterized in that it contains a copoly as water-soluble builder component, the copolymer comprising 60-95% by weight, preferably 70-90% by weight, of (meth) acrylic acid or (meth) acrylate , preferably acrylic acid or acrylate, and maleic acid or maleate and 5-40% by weight, preferably 10-25% by weight, of vinyl alcohol and / or vinyl acetate, the weight ratio being (meth) acrylic acid or (meth) acrylate to maleic acid or Maleate is between 1.5: 1 and 4: 1, preferably between 2: 1 and 2.5: 1, both the amounts and the weight ratios are based on the acids, and a copolymer of the salts of the acids and vinyl alcohol is preferred are moving.

The copolymers used according to the invention can be prepared by any of the known and customary processes. In particular, (meth) acrylic acid, preferably acrylic acid, and maleic acid are reacted with vinyl alcohol and / or vinyl acetate, whereupon the acids may then be neutralized to preferably their alkali metal salts, such as the sodium or potassium salts or ammonium salts or alkanolamine salts, such as the monoethanol insole the triethanolamine salt, and optionally a partial or complete cleavage of the vinyl acetate to the vinyl alcohol is carried out.

Analogous to the known (co) polymeric polycarboxylic acids or polycarboxylates such as the ho- or copolymeric acrylic acids or acrylates, preference is given to copolymers which are either completely or at least partially, in particular to more than 50%, based on the existing carboxyl groups are neutralized. A completely neutralized copolymer is particularly preferred, ie it consists of the salts of (meth) acrylic acid, preferably acrylic acid, and maleic acid, in particular the sodium or potassium salts, and vinyl alcohol. The copolymers generally have a relative molecular mass between 1000 and 200000, preferably between 2000 and 50,000, and in particular between 3000 and 10,000. They are preferably used in powder-sprayed form. Particularly preferred copolymers are produced by a process which is described in the earlier German patent application P 43 00 772.4.

Preferred dishwashing detergents according to the invention contain the copolymer in amounts of 0.5 to 30% by weight, preferably 2 to 20% by weight, furthermore 0.5 to 20% by weight, preferably 5 to 15% by weight, of a bleaching agent based on oxygen, in particular alkali perborate and / or percarbonate, and nonionic surfactants in an amount of at most 5% by weight, preferably at most 2% by weight, the agents being free from anionic, cationic or amphoteric surfactants.

In a preferred embodiment, alkali metal carbonates and / or hydrogen carbonates, in particular the sodium salts, are present as alkali carriers in an amount of up to 60% by weight, preferably 5 to 50% by weight.

The dishwashing detergents according to the invention can contain further water-soluble builder components, such as synthetic polymers, which include the salts of polymerization products of unsaturated carboxylic acids and which include, for example, polyacrylates, polymethacrylates, polymaleinates or copolymers of acrylic acid with maleic acid or maleic anhydride, in an amount of 0.5 Contain up to 30 wt .-%, preferably 2 to 20 wt .-%. Suitable polyacrylates are, for example, Alcosperse ( ^R ) 102, 104, 106, 404, 406 from Alco, Acrysole ( ^R ) A Nl, LMW 45 N, LMW 10 N from Norsohaas, Degapas ( ^R ) from Degussa; Suitable copolymers of polyacrylic acid and maleic acid are, for example, Sokalan ( ^R ) CP 5, CP 7 from BASF, Acrysol ( ^R ) QR 1014 from Norsohaas, Alcosperse ( ^R ) 175 from Alco. In principle, phosphates or zeolites can also be present, but the dishwashing detergents are preferably free from zeolites and from phosphate-containing bath components.

In the case of the surfactants which can be used in the agents according to the invention, their foaming behavior is decisive. Low-foam connections are preferred because of the machine mechanics. Above all, these are nonionic surfactants; The dishwashing detergents according to the invention are therefore preferably free of anionic, cationic or amphoteric surfactants. The content of nonionic surfactants is at most 5% by weight, preferably at most 2% by weight. Addition products of 1 to 20 moles of ethylene oxide (E0) and / or 1 to 20 moles of propylene oxide (PO) with 1 mole of an aliphatic compound with 10 to 20 carbon atoms from the group of alcohols, carboxylic acids, fatty amines and carboxamides are the nonionic surfactants and alkanesulfonamides of interest. In addition to the water-soluble nonionic surfactants, polyglycol ethers with 2 to 7 ethylene glycol ether residues in the molecule, which are not or not completely water-soluble, are also important, preferably in combination with water-soluble nonionic ones Surfactants used. In addition, alkyl polyglycosides of the general formula R-0- (G) _x can also be used as nonionic surfactants, in which R denotes a primary, straight-chain or branched aliphatic radical having 8 to 22, preferably 12 to 18 C atoms, G for a glyco - Se unit with 5 or 6 carbon atoms and the degree of oligomerization x is between 1 and 10.

Preferred dishwashing detergents according to the invention also contain complexing agents from the group of the di- and honorically functional organic carboxylic acids or their salts, e.g. Nitrilotriacetic acid, but especially citric acid or its salts, in an amount of 0.5 to 60% by weight, preferably 20 to 50% by weight.

The usual alkalizing agents used in low-alkaline machine dishwashing detergents include alkali carbonates, hydrogen carbonates and alkali silicates with a molar ratio SiO 2 / M2 O (M = alkali metal) of 1.5: 1 to 2.5: 1 alkali carbonates and bicarbonates preferably used are the sodium carbonates and bicarbonates which are contained in the amounts already mentioned above. The use of the highly alkaline metasilicates as alkali carriers is preferably avoided. Instead of the metasilicates, preference is given to alkali silicates, preferably sodium silicates, with a SiO 2 Na 2 O molar ratio of 1.5: 1 to 2.5: 1, in amounts of up to 30% by weight, preferably 5 to 20% by weight, based on the entire dishwashing detergent used.

Among the compounds serving as oxygen-based bleaching agents, sodium perborate tetrahydrate (NaBÜ2 ^• H2O2 ^• 3H2O), sodium perborate monohydrate (aBÜ2 ^• H2O2) and peroxycarbonate (Na2C03 ^• 1.5 H2O2) are of particular importance. Other bleaching agents that can be used are, for example, peracidic salts of organic acids, such as perbenzoates or salts of diperdodecanedioic acid. It preferably contains 0.5 to 20% by weight, particularly preferably 5 to 15% by weight, of an oxygen-based bleach, in particular alkali perborates and / or percarbonates. In addition, the addition of small amounts of known bleach stabilizers such as borates or metaborates and metasilicates and magnesium salts, for example magnesium sulfate.

Suitable bleach activators for these oxidizing agents are in particular N-acyl and O-acyl compounds, preferably tetraacylated diamines such as N, N, N '.N'-tetraacetylethylene diamine in (TAED). The agents according to the invention contain such conventional bleach activators in an amount of 0.1 to 10% by weight, preferably 1 to 5% by weight. The agents according to the invention are preferably free from agents that release active chlorine, e.g. Trichloroisocyanuric acid.

Enzymes such as proteases, aylases, lipases or cellulases can be used to better remove protein or starch-containing food residues, for example proteases such as BLAP () 140 from Henkel, 0ptimase ( ^R ) -M-440, 0ptimase ( ^R ) -M -330, 0pticlean ( ^R ) -M-375, 0pticlean ( ^R ) -M-250 from Solvay Enzy es, Maxacal ( ^R ) CX 450,000, Maxapem ( ^R ) from Ibis, Savinase ( ^R ) 4.0 T, 6.0 T, 8.0 T from Novo or Experase ( ^R ) T from Ibis; Amylases such as Termamyl ( ^R ) 60 T, 90 T from Novo, A ylase-LT ( ^R ) from Solvay Enzymes or Maxamyl ( ^R ) P 5000, CXT 5000 or CXT 2900 from Ibis; Lipases such as Lipolase ( ^R ) 30 T from Novo; Cellulases such as Celluzym ( ^R ) 0.7 T from Novo Nordisk. Enzymes are contained in the agents according to the invention in an amount of 0.1 to 5% by weight, preferably 0.5 to 2% by weight, based on the total dishwashing detergent.

To prevent tarnishing of silver cutlery, optional silver protection agents, as described in the older German patent application P 43 15 397.6, in particular water-soluble Mn (II) salts, in an amount of up to 2% by weight, preferably 0. 1 to 0.5 wt .-%, may be included.

The dishwashing detergents according to the invention are preferably in the form of powdery, granular or tablet-like preparations which can be prepared in a conventional manner, for example by mixing, granulating, roller compacting and / or by spray drying. It is also possible for the polymers used according to the invention to be in the form of a compound can be used as an additive component to other granular components of the dishwashing detergent.

To produce cleaning agents according to the invention in tablet form, the procedure is preferably such that all constituents are mixed with one another in a mixer and the mixture is used by means of conventional tablet presses, for example eccentric presses or rotary presses, with pressures in the range from 200 ^· 10 ^ Pa to 1 500 ^• 10 ^ Pa pressed. In this way, break-resistant tablets are obtained which, under application conditions, dissolve sufficiently quickly, with bending strengths of normally over 150 N. Preferably, a tablet produced in this way has a weight of 15 g to 40 g, in particular 20 g to 30 g, with a diameter from 35 m to 40 mm.

The production of machine dishwashing detergents in the form of non-dusting, storage-stable, free-flowing powders and / or granules with high bulk densities in the range from 800 to 900 g / 1 is characterized in that in a first process stage, the builder components are at least partially liquid Mixing components are mixed while increasing the bulk density of this premix and subsequently - if desired - after an intermediate drying - the further components of the dishwasher detergent are combined with the premix obtained in this way.

Since the alkali carbonate content strongly influences the alkalinity of the product, the intermediate drying must be carried out so that the decomposition of the sodium bicarbonate to sodium carbonate is as low as possible (or at least as constant as possible). An additional sodium carbonate portion resulting from the drying would have to be taken into account when formulating the ^Λ granulate recipe. Low drying temperatures not only counteract sodium bicarbonate decay, but also increase the solubility of the granulated detergent during use. It is therefore advantageous for drying to have a supply air temperature which, on the one hand, should be as low as possible to avoid bicarbonate decomposition and, on the other hand, must be as high as necessary in order to obtain a product with good storage properties. When drying, a supply air is preferred. te temperature of approx. 80 ° C. The granules themselves should not be heated to temperatures above about 60 ° C.

In the first sub-stage of the mixing process, the builder is generally acted upon with at least one further component of the dishwashing agent with the liquid components. For example, a precursor may be considered in which the builder component, mixed with perborate, is acted upon by the liquid nonionic surfactants and / or the solution of the fragrances and mixed intimately. The remaining components are then added and the entire mixture is worked through and homogenized in the mixing device. The use of additional amounts of liquid, in particular the use of additional water, is generally not necessary here. The mixture of substances obtained is then in the form of a free-flowing, dust-free powder of the desired high bulk densities, approximately in the range from 800 to 900 g / l.

The pre-granules are then mixed with the still missing components of the dishwashing detergent to form the finished product. In all the cases shown here, the mixing time is both in the preliminary stage of the compacting mixture under the influence of liquid components and in the subsequent final mixture with the other components in the range of a few minutes, for example in the range of 1 to 5 minutes.

In a special embodiment, it may be expedient in the production of fine granules to set further stabilization and leveling by powdering the surface of the granules formed. Small portions of water glass powder or powdered alkali carbonate are particularly suitable for this purpose.

With the automatic dishwashing agents according to the invention, products are available which, in addition to their better biodegradability, are superior to conventional modern dishwashing agents above all with regard to the deposit inhibition and the rinse aid effect on glasses and knife blades.

The following examples are intended to explain the subject of the invention in more detail, but without restricting it thereto. Examples

Granular dishwashing detergents with the following composition (agent A according to the invention and comparative agent B and agent C according to the invention) were produced.

Agent A contained 10% by weight of the copolymer which, according to the disclosure of the earlier German patent application P 43 00 772.4, was prepared from 80% by weight of acrylic acid and maleic acid in a weight ratio of 7: 3 and from 20% by weight of vinyl acetate and then completely neutralized had been.

Comparative Example B contained 10% by weight of an acrylate-maleate copolymer sold by BASF under the trade name Sokalan ( ^R ) CP5.

A B C

% By weight% by weight% by weight

Na citrate 30.0 30.0 40.0

Sokalan CP5 - 10.0 - above Copolymer 10.0 - 5.0

Na2C03 13.0 13.0 6.0

NaHC03 35.5 35.5 30.1

Na perborate 5.0 5.0 -

Na percarbonate - - 12.0

TAED 2.0 2.0 3.0

Amylase 1.5 1.5 1.0

Protease 1.5 1.5 1.0

Plurafac LF403 from BASF

(C ^ / iβ-fatty alcohol x E0 x 4 PO) 0.9 0.9 0.9 perfume oil 0.6 0.6 0.6

MnSθ4 0.4 Reiπiqunosleistunq

The cleaning performance of agents A and B was tested in a dishwasher Miele G 531 (program Universal 65 ° C) at doses of 30 g each in 7.0 l water with 16 ° dH in the cleaning cycle (soiling as in "Th. Altenschöpfer , SÖFW, 98 (1972) 763-765 ": tea, milk, minced meat, pudding, fat stick, starch, oatmeal).

Agent A according to the invention had a superior cleaning performance compared to agent B not according to the invention, particularly when removing the starch, minced meat, fat stick and oatmeal stains, but in particular when staining tea.

Belaqsinhibierunq

The buildup of agents A and B was carried out in a Miele G 590 dishwasher (Universal 65 ° C program) at doses of 20 g each in 7.0 l of water at 16 ° dH with the addition of 50 g of pumpable soiling (mixture of ketchup, gravy , Mustard, potato starch, egg yolk, milk, margarine) in the presence of 3.0 ml of a commercial rinse aid tested over 10 rinse cycles. The rinsing effect ("spotting") was rated on a scale from 1 (= very bad rinsing effect) to 8 (= very good rinsing effect, no water stains). The results of the rinsing effects achieved with agent A according to the invention and comparative agent B on glasses, knife blades and porcelain plates can be seen in Table 1.

Table 1

Glasses

Knife blades

Porcelain plate

It can be seen that agent A according to the invention is superior to comparative agent B above all with regard to the rinse aid effect on glasses and knife blades.

Agent C according to the invention showed cleaning and deposit inhibition performances comparable to agent A according to the invention; due to the presence of MnSÜ, it showed superior properties especially in preventing silver tarnishing from tarnishing.

Claims

claims

1. Low-alkaline agent for machine cleaning of dishes, whose 1% by weight aqueous solution has a pH of 8 to 11.5, preferably 9 to 10.5, containing water-soluble builder components and bleaching agents for oxygen -Base, characterized in that a copolymer is present as the water-soluble builder component which comprises 60-95% by weight, preferably 70-90% by weight, of (meth) acrylic acid or (meth) acrylate, preferably acrylic acid or Acrylate, and maleic acid or maleate and 5-40% by weight, preferably 10-25% by weight, of vinyl alcohol and / or vinyl acetate, the weight ratio of (meth) acrylic acid or (meth) acrylate being increased Maleic acid or maleate is between 1.5: 1 and 4: 1, preferably between 2: 1 and 2.5: 1, both the amounts and the weight ratios are based on the acids, and a copolymer of the salts of Acids and vinyl alcohol are preferred.

2. Composition according to claim 1, characterized in that it is 0.5 to 30 wt .-%, preferably 2 to 20 wt .-% copolymer and 0.5 to 20 wt .-%, preferably 5 to 15 wt .-% , an oxygen-based bleach, in particular alkali perborate and / or percarbonate, and that it is free of anionic, cationic or amphoteric surfactants and the content of nonionic surfactants max. 5% by weight, preferably max. 2 wt .-%, each based on the total agent.

3. Composition according to claim 1 and 2, characterized in that it contains up to 60 wt .-%, preferably 5 to 50 wt .-%, alkali carbonate and / or hydrogen carbonate.

4. Composition according to claim 1 to 3, characterized in that there are complexing agents from the group of the di- and polyfunctional organic carboxylic acids or their salts, in particular citric acid or their salts, in an amount of 0.5 to 60 % By weight, preferably 20 to 50% by weight, based on the total agent. 5. Composition according to claim 1 to 4, characterized in that it is up to 30 wt .-%, preferably 5 to 20 wt .-%, based on the total Mit¬ tel, alkali silicate with a molar ratio Siθ2 / 2θ (M = alkali atom ) from 1.5: 1 to 2,

5: 1 contains, ι

6. Composition according to claim 1 to 5, characterized in that it is free of active chlorine-releasing agents.

7. Composition according to claim 1 to 6, characterized in that it contains enzymes in an amount of 0.1 to 5 wt .-%, preferably 0.5 to 2 wt .-%, based on the total agent.

8. Tablet-like composition according to claim 1 to 7, characterized gekennzeich¬ net that it by mixing all of its components in a mixer and pressing the mixture by means of a tablet press at pressures of 2 ^• 10 ⁷ Pa to 1.5 ^• 10 ⁸ Pa is available.

9. Powder or granular composition according to claim 1 to 7, characterized in that it has a bulk density of 750 g / 1 to 1000 g / 1.

10. Use of the agent according to one of claims 1 to 9 for mechanically cleaning dishes.