DE2645209C2 - Rinse aid for machine washing of objects with hard surfaces - Google Patents

Description

The invention relates to rinsing agents based on acidic phosphoric acid esters for machine washing from objects with a hard surface, such as B. dishes or glasses or means of transport in automatic washing devices or washing systems, whereby the rinse aid does not foam in water and give the dishes a glossy dry effect.

It is known that in machine dishwashing the cleaned dishes in connection with the actual cleaning process in a rinsing bath to achieve of a glossy crockery with a residue-free surface is treated with the rinse aid special rinse aid can be added. It is desirable that this rinse aid be a good one Have wetting power so that the rinse water runs off the dishes in a film-like manner and does not leave any residue such as limescale stains or other dirt.

The known rinse aids generally consist of mixtures of different chemical substances, each substance has a specific function in the rinsing process. Such rinse aid contain, for example, a wetting agent in the form of a detergent substance, anionic, cationic or non-ionic, alcohols as foam inhibitors, an acidic component to prevent limescale and limescale stains on the surface of the dishes and optionally perfume and dye as further Additions. '.- ..;

In the German Offenlegungsschrift 19 26 684 a rinse aid is disclosed, which as. Wetting agent water-soluble sulfonated condensation product of a phenol, an alkylpheno! or, a naphthol and formaldehyde with a certain molecular weight. Such a wetting agent is proportionate

ίο low-foaming, but by no means non-foaming describe. The known rinse aid formulation can also contain an organic acidic component Carboxylic acid such as citric acid, tartaric acid or gluconic acid contain.

The disadvantage of the aforementioned rinse aid formulation is the need for a large number of different ones chemical substances to have to use a low-foaming detergent with a satisfactory To get the rinsing effect. Such detergent formulations are relatively expensive.

Another rinse aid is disclosed in German Offenlegungsschrift 21 44 425 and consists of aliphatic and / or cycloaliphatic phosphoric acid mono- and / or diesters with 1-8 carbon atoms per alcoholic component of the ester, optionally mixed with phosphoric acid. Both Short-chain phosphoric acid mono- and / or diesters result from their strong odor Substances have aesthetic reservations, especially after this inherent odor, even with strong perfuming cannot be suppressed.

The object was therefore to develop rinse aid which would have the disadvantages of the known rinse aid do not have and are also characterized by an increased rinse effect.

The rinse aid of the invention based on acidic phosphoric acid esters for machine washing of objects with hard surfaces is characterized in that it is a mixture of acidic orihophosphorsäureestem, which is made by reacting phosphorus V-oxide with a mixture consisting of a monohydric alcohol with 1-8C atoms and an alkane polyol with 2 to ^ C atoms and 2 to 6 hydroxyl groups, while maintaining a molar ratio of phosphorus V-oxide to monohydric alcohol to alkane polyol of 1 to 2 to V _n , where π is the number of Hydroxyl groups in the alkane polyol molecule means with mixing or kneading of the reaction components at a temperature between about 0 °

so and 120 ⁰ C with exclusion of moisture and in the presence of an inert gas in the course of about 1-6 hours and cooling of the reaction mixture after the end of the reaction.

According to a preferred embodiment of the invention, the rinse aid is a mixture acidic orthophosphoric acid esters, which by reacting phosphorus V-oxide with a mixture, consisting of n-butanol and ethylene glycol or diethylene glycol or isopropanol and glycerin became. Instead of the alcohol mixtures mentioned above, a mixture consisting of ethylene glycol can also be used and the adduct of 4 moles of ethylene oxide and 1 mole of lauryl alcohol. It is advantageous to give that Rinse aid in the washing liquid in an amount of 3-100 mg per liter, preferably 30-70 mg per liter Rinsing liquid.

The rinse aid according to the invention have the advantage over the known rinse aid that they

to

15th

at the same concentration in the rinsing liquid result in an improved clear gloss effect and have a weak inherent odor, so that a special No need for perfuming to cover up the inherent odor. In addition, additions of weak foaming wetting agents or other acidic components such as citric acid and the like necessary. After all, they are physiologically harmless and biodegradable.

The following examples serve to explain the invention in more detail without, however, referring to it restrict.

example 1 a) Preparation of the rinse aid:

333 g (4.5 mol) of n-butanol and 279 g (4.5 mol) of ethylene glycol were mixed in a 21 glass vessel with a stirrer under a nitrogen atmosphere, and 1.8 g of phosphorous acid were added to the mixture. 639 g (225MoI) of P4O10 were then added to the mixture in the course of 110 min, the mixture being cooled from the outside with a water-ice mixture. The temperature of the reaction mixture rose from 22 ° C. to 55 ° C. during the introduction. After the exothermic reaction had subsided, the mixture was heated to 80 ° C. within one hour and kept at 80-85 ° C. for 3 hours. After cooling, 1250 g of a colorless, viscous liquid with a P4O10 content of 51 2nd % by weight, an acid number up to the first turning point of the titration curve at a pH value of about 4.5 of 331 mg KOH / g and a total acid number up to the 2nd inflection point at a pH of 9.5 of 564 mg KOH / g. The product had a density d » ²⁰ of 1.438 g / cm ³ . The dynamic viscosity was 676 poise at 20 ° C, at 50 ° C 65 poise, and at 8O ⁰ C 21 poise. The product can be mixed with water in any proportion. The product also dissolves in short-chain aliphatic alcohols, '.vie ζ. Β. Methanol, ethanol and isopropanol.

b) Using the rinse aid:

6 smooth, cup-shaped and 6 goblet-shaped drinking glasses were placed in a household dishwasher cleaned in one cleaning cycle and then with an aqueous solution of the rinse aid rinsed clear In the cleaning cycle, the rinsing liquid contained 40 g / liter of a cleaning agent mixture consisting of so

Strips with the dishes determined. The cleaning and rinsing process was 10 times for a certain concentration of the rinse aid in the rinse aid water repeated and the statistical mean of the 10 rinsing cycles determined as the final value for the clear gloss effect Zaiilen for spots and stripes counted here The results obtained are shown in the table, column II, the dependence of the clear gloss effect on the concentration of the rinse aid in the Rinsing liquid is expressed.

Example 2 (Comparative example)

The procedure was analogous to Example 1, except that monobutyl phosphate was used as the rinse aid. The results obtained are in the table, Column III shown.

Tabel

Attempt no. I. 5 II III 1 10 268 300 2 20th 230 274 3 30th 168 198 4th 40 98 180 5 50 63 150 6th 60 66 112 7th 70 52 75 8th 80 35 73 9 90 63 91 10 72 156

Column I: Concentration of the KU dishwashing liquid in the aqueous dishwashing liquid (mg / liter).

Column II: Number of spots and streaks when used of the rinse aid according to Example 1.

Column III: Number of spots and streaks when using the rinse aid according to Example 2.

56% by weight pentasodium triphosphate 35% by weight sodium metasilicate 5% by weight soda 2% by weight sodium dichloroisocyanurate

dihydrate as well

2% by weight of an adduct of 12 moles of ethylene oxide and one mole of one Fatty alcohol with 16 carbon atoms

Following the cleaning cycle, the items to be washed were rinsed clear with an aqueous solution of the rinse aid of a certain concentration and the Clear gloss effect on the items to be washed in a reflection-free black light box, as described by Th. Altenschöpfer in "Seifen-Öle-Fette-Wachse", Volume 98, No. 24/1972 is described by counting the stains and From the table it can be seen that with the same concentrations of rinse aid according to the invention Rinse aid gives a better clear gloss effect than the known comparative product.

Example 3

Following the automatic cleaning of railroad passenger coaches in a washing system with rotating brushes, a 5 percent by weight aqueous solution of a cleaning agent Mixture of

6% by weight secondary Ci ₃ -Ci ₈ alkyl sulfate 5% by weight nonylphenol ethoxylate with 8 mol

Ethylene oxide

2% by weight polyglycol 10% by weight 35% orthophosphoric acid 20% by weight monomethyl phosphate and 64% by weight water

was used, the window panes of the passenger coach to achieve a clear shine with a 0.005 weight percent aqueous solution of the rinse aid according to Example 1 sprayed.

In the cleaning process, the cars passed a brush stand and were then fed to the separately arranged window spray stand, in which only

the panes were sprayed with the aforementioned spray solution. Then the car was left to dry parked outdoors Within a series of tests lasting over 4 weeks, passenger coaches were included Cleaned for different degrees of soiling In all cases the window panes show a flawless clear gloss effect without island or drop formation and did not have to be repolished by hand will. To produce the rinsing liquid, water with a hardness of 24 ° German was used, with the addition of complexing agents or other aids was dispensed with.

Claims (4)

Patent claims: 1. Rinse aid based on acidic phosphoric acid esters for machine washing of objects with a hard surface, characterized in that it is a mixture of acidic orthophosphoric acid esters, which is obtained by reacting phosphorus V-oxide with a mixture consisting of a monohydric alcohol with 1-8 carbon atoms and an alkane polyol with 2 to 12 carbon atoms and 2 to 6 hydroxyl groups, while maintaining a molar ratio of phosphorus V-oxide to monohydric alcohol to alkane polyol of 1 to 2 to ^A U where η is the number of hydroxyl groups in Alkanpolyolmolekül with mixing or kneading the reaction components at a temperature between about 0 ° and 120 ⁰ C under exclusion of moisture and in the presence of an inert gas over a period of about 1-6 hours and cooling the reaction mixture after the termination means of the reaction was obtained. 2. Composition according to claim 1, characterized in that it is a mixture of acidic orthophosphoric acid esters represents, which by reacting phosphorus V-oxide with a mixture consisting of n-butanol and ethylene glycol or diethylene glycol or isopropanol and glycerol was obtained. 3. Composition according to claim 1, characterized in that it is a mixture of acidic orthophosphoric acid esters represents, which by reacting phosphorus V-oxide with a mixture consisting of Ethylene glycol and the adduct of 4 moles of ethylene oxide and 1 mole of lauryl alcohol are obtained became. 4. Use of the agent according to claim 1-3 in the flushing liquid in an amount of 3-100 mg per liter, preferably 30-70 mg per liter.