WO1996015215A1

WO1996015215A1 - Cleaning agent

Info

Publication number: WO1996015215A1
Application number: PCT/SE1995/001320
Authority: WO
Inventors: Jan-Olof Eriksson
Original assignee: Eriksson Jan Olof
Priority date: 1994-11-10
Filing date: 1995-11-08
Publication date: 1996-05-23
Also published as: AU3942795A; SE9403865L; SE9403865D0; SE504774C2

Abstract

The present invention relates to an acid cleaning agent which contains low alkanol amine hydrochloride and which is intended particularly for use as a dishwashing detergent.

Description

Cleaning agent

The present invention relates to an acid cleaning agent, particularly an acid dishwashing agent, and more particularly to a cleaning agent for use in the food industry.

Effective cleaning agents, particularly dishwashing detergents, according to the present standpoint of techniques, are generally highly basic and have a pH above 10. Acid detergents are known to the art, but because such detergents precipitate proteins, they are not suitable for use as dishwashing agents, but are used primarily to neutralize lime deposits in conjunction with cleaning sanitary spaces. From an environmental aspect, a dishwashing agent will preferably have a pH of between 2 and 10 and will not be corrosive. Cleaning agents that have a neutral pH, however, have been found to be relatively ineffective. DuPont has produced an acid dishwashing agent that contains glycolic acid. This dishwashing agent, however, precipitates proteins.

There is at present a need for acid cleaning agents, particularly in the food industry (e.g. for cleaning milk tanks in the farming and dairy industries). Acid cleaning agents are extremely useful, because they dissolve and loosen lime deposits effectively. However, one drawback with such cleaning agents is that they also precipitate proteins which form adhesive surface coatings.

The object of the present invention is to provide an effective cleaning agent, particularly a dishwashing agent, that has a low pH and does not have those drawbacks and limitations associated with such agents, such as protein precipitation for instance. The invention is based on the surprising effect that is obtained when the solvent used in the cleaning agent is a low alkanol amine hydrochloride. The cleaning agent also includes an acidifying acid and a suitable grease-dissolving surfactant. The cleaning agent may also include selectively other conventional additives, such as anti-foaming agent, thickening agent and an odorant. The inventive cleaning agent is not corrosive, will dissolve fat (grease) and lime deposits effectively, and does not precipitate proteins as opposed to conventional acid cleaning agents.

The alkanol groups in the low alkanol amine hydrochloride may be the same or different and each contains up to 8 carbon atoms, such as 1-4 carbon atoms, and particular¬ ly 2 carbon atoms. A preferred low alkanol amine hydrochloride is ethanolamine hydroch- loride, particularly diethanolamine hydrochloride. The amount of low alkanol amine hydrochloride in the cleaning agent may be varied within wide limits, depending on whether the cleaning agent is in the form of a ready-to-use solution or in concentrated form. The acid used to adjust the pH of the cleaning agent is preferably hydrochloric acid. The pH can be varied between 0 and 7, depending on the use for which the cleaning agent is intended. Berol 226^® has been found to be a suitable surfactant in this regard. (Berol 226^® is a surfactant which contains a quartenary coconut amine, a non-ionic surfactant having about 90 ethylene oxide units and glycol ether and retailed by Berol Nobel AB.) Alternati¬ vely, other surfactants of anionic, cationic or non-ionic type may be used, and can be selected by the person skilled in this art on the basis of simple routine tests. Diethanolamin hydrochloride used in the inventive cleaning agent is produced by mixing diethanolamine with an equivalent amount of hydrochloric acid. The total end product of this reaction is hereinafter referred to as a diethanolamine hydrochloride solution. If not otherwise mentioned, all percentages mentioned in the following are percentages by volyme.

The inventive cleaning agent includes an aqueous solution comprising 1-90% diethanolamine hydrochloride solution according to the above, particularly 10-80%, and more particularly 45-55%, an acid in an amount to obtain a pH lower than 7, particularly lower than 5 and more particularly lower than 2, 1-20% , preferably 4-15 % , of a suitable fat-dissolving surfactant and selected conventional additives.

A particularly preferred cleaning-agent composition for use as a dishwashing detergent is 50% diethanolamine hydrochloride solution, 4% suitable fat-dissolving surfactant, preferably Berol 226^®, hydrochloric acid to obtain a pH of about 1 , thickening agent and the remainder water. Example 1

There was prepared a cleaning agent containing an aqueous solution of 50% diethanolamine hydrochloride solution and 4 % Berol 226^®. The solution had a pH of about 7.5. The cleaning agent was divided into six beakers and different amounts of hydrochloric acid were added to respective beakers to adjust the pH to about 1.0, 2.0, 3.0, 4.0, 5.0 and 6.0 respectively. Respective cleaning agents were tested on typically dirty dishes in a domestic dishwasher at 60 °C. Each cleaning agent was poured into the machine-powder compartment of the dishwasher in an amount normal with such machines. The cleaning effect of the detergent was assessed by ocular examination, and respective dishwashing detergent were certified as being very good, good, acceptable or unacceptable, depending on the amount of dirt patches remaining on the dishes. The results are set forth in Table 1 below. Table 1

pH Result

- 1.0 Very Good

-2.0 Good

-3.0 Acceptable

-4.0 Acceptable

-5.0 Unacceptable

-6.0 Unacceptable

The Table shows that effective dishwashing is achieved at pH equal to or lower than 2.0. Examples of preferred embodiments for other areas of use:

Degreasing agent: 40% DEAHC (diethanolamine hydrochloride) + an HCl excess to obtain a pH of about 2.5, and 15% surfactant.

Lime removing agent: 20% DEAHC + an excess of HCl to obtain a pH of about 4, and about 4% surfactant.

Sanitary cleaning agent: 10% DEAHC + a excess of HCl to obtain a pH of 5, and about

6-7% surfactant.

Industrial lime cleaning and degreasing agent: 40% DEAHC + a excess of HCl to obtain a pH of about 0, and 10% surfactant. It will be evident from the aforegoing that the present invention satisfies the need for an effective acid cleaning agent.

A thickener can be added, to facilitate handling of the cleaning agent, with respect to dispensing the cleaning agent in measured quantities. The cleaning agent can also be treated in the same way as existing liquid detergents with regard to extra additives, treatment, packaging, etc.

Claims

1. An acid cleaning agent, characterized in that the cleaning agent contains low alkanol amine hydrochloride.

2. An acid cleaning agent according to Claim 1, characterized in that the low alkanol amine hydrochloride is diethanolamine hydrochloride.

3. An acid cleaning agent according to Claim 2, characterized in that it contains 1-90 vol%, preferably 20-80 vol% , and in particular 45-55 vol% diethanolamine hydroch¬ loride.

4. An acid cleaning agent according to Claim 1, characterized in that its pH is below 7, preferably below 5 and more preferably below 2.

5. An acid cleaning agent according to Claim 4, characterized in that it is acidified with hydrochloric acid.

6. An acid cleaning agent according to Claim 1, characterized in that it contains a surfactant, particularly a low-foaming surfactant.

7. An acid cleaning agent according to Claim 6, characterized in that the surfactant constitutes 1-20 vol%, preferably 4-15 vol%.

8. The use of the cleaning agent according to Claims 1-7 as a dishwashing detergent.

AMENDED CLAIMS

[received by the International Bureau on 4 Apri l 1996 (04.04.96) ; original claims 1-8 replaced by amended claims 1 -6 ( 1 page) ]

1. An acid cleaning agent for use in the industry, characterized in that the cleaning agent contains low alkanol amine hydrochloride and hydrochloric acid to obtain a pH lower tiian 2.

3. An acid cleaning agent according to Claim 2, characterized in that it contains 1-90 vol%, preferably 20-80 vol%, and in particular 45-55 vol% diethanolamine hydrochloride.

4. An acid cleaning agent according to Claim 1, characterized in that it contains a surfactant, particularly a low-foaming surfactant.

5. An acid cleamng agent according to Claim 4, characterized in that the surfactant constitutes 1-20 vol%, preferably 4-15 vol% . 6. The use of the acid cleaning agent according to Claims 1-5 in the food industry, particularly as a dishwashing detergent.