GB2084875A - Iodophor powder composition - Google Patents

Abstract

An iodophor powder composition for use as a cleaning and/or sanitizing agent, which shortly before use is dissolved in water and diluted to provide a solution having a suitable iodine concentration. The composition includes an iodide salt such as potassium iodide; an oxidising agent, such as sodium perborate, for releasing iodine from the iodine salt in the solution; a polymer, such as polyvinylpyrrolidone, for absorbing the released iodine and subsequently releasing the absorbed iodine to the solution at a slower rate; and an acid for providing an acidic medium.

Description

SPECIFICATION lodophor powder composition This invention relates to an iodophor composition which may be used as a cleaning and/or sanitizing agent. In particular the invention relates to an iodophor composition which may be used for cleaning and/or sanitizing in power stations, dairies, breweries, abattoirs, butcheries, or the like, According to the invention, there is provided an iodophor powder composition which comprises an iodide, salt; an oxidising agent which is stable in the dry form, and is capable of releasing iodine from the iodide salt in a solution formed by dispersing the powder composition in water; a polymer capable of forming a polymer-iodine complex and of subsequently making available a soluble form of the iodine; and an acid.

The composition is dissolved in water shortly before use, the acid constituent providing an acidic medium in which the iodide and oxidising agent react to liberate iodine which forms a polymer-iodine complex with the polymer. The polymer-iodine complex is in turn dissolved in the water to form a stable iodine solution which has cleaning and sanitizing properties, the polymer-iodine complex making available a soluble form of iodine for cleaning/sanitizing. The acid, further, may serve as an additional cleaning agent, for example for descaling cooling towers, removal of milk scale in dairies and beerstone in breweries.

The iodide may be an alkali metal iodide, such as sodium iodide and potassium iodide, or any other suitable metal iodide.

The oxidising agent may be sodium perborate or any other suitable oxidising agent of the large range available, provided only that it is stable in the dry form.

The polymer may be polyvinylpyrrolidone, or any other suitable polymer.

The acid may be organic or inorganic. For example, the acid may be selected from the group consisting in sulphamic acid, citric acid, and sodium bisulphate. The acid should be in powder form, and in this regard acid is used broadly to include a soluble powder, e.g. an acid anhydride, which will not adversely affect the iodine solution's cleaning properties, but which will dissolve to provide an acid solution.

The iodophor composition may also include a filler material which serves to reduce the proportion of active ingredients present in the composition, to facilitate use, handling, dispensing, etc., of the composition and combat accidental excessive and hence expensive consumption of the active ingredients.

The filler material may thus comprise an inert, water-soluble salt such as sodium chloride, sodium sulphate, or the like, which will not adversely affect the stability of the dry powder iodophor composition, and will not be active in an aqueous solution thereof to adversely affect the solution's cleaning/sanitizing properties.

Further, the iodophor composition may include a surfactant such as nonyl phenol ethoxylate or a linear alcohol, which may serve as a wetting agent for the acid, thus enchancing its penetrating and hence its cleaning action, and may further serve to provide the composition with detergent properties.

Thus, for a dairy and its equipment for example, a single-stage cleaning process may be provided, the surfactant, as a detergent, removing fatty substances; the acid removing milk scale and like deposits; and the released iodine serving to clean and sanitize generally.

The surfactant may be in the form of a powder or a liquid. When the surfactant is a liquid, the volume included in the composition of the invention must be limited to the value that will still provide a powder composition.

Hence, the maximum suitable proportion of liquid surfactant is about 25% by weight of the composition in which it is included.

The iodophor powder composition in which the surfactant is a liquid, may include an absorbent carrier material wherein the liquid surfactant is absorbed, to maintain a dry powder form of the iodophor composition. The absorbent carrier material may be a suitable silica for example.

The relative proportions of the essential constituents of the iodophor composition of the invention may be varied within certain limits. For example, an iodophor composition comprising potassium iodide, sodium perborate, polyvinylpyrrolidone, and sulphamic acid, may include 0.5 to 1 5% by weight of potassium iodide as the iodide salt, 0.5 to 25% by weight of sodium perborate as the oxidising agent, 0.5 to 30% by weight of polyvinylpyrrolidone as the polymer, and 0.5 to 98.5% by weight of sulphamic acid as the acid.

The relative proportions of the constituents may be determined by the particular application for which the composition is intended.

For example, when the composition is used for cooling towers, its descaling property will assume greater importance than its sanitizing property, and the composition will include preferably a relatively high proportion of the acid and a relatively low proportion of the iodide which can nevertheless act as a slimicide. On the other hand, when the composition is used in dairies, its cleaning and sanitizing properties are the more important, and then the composition will include preferably a relatively high proportion of the iodide.

It will be appreciated that the required proportion by weight of a particular metal iodide in the composition will also depend upon the relative atomic weights of the metal and the iodine constitutents of the iodide. If, for example, a first metal with a low atomic weight were replaced by a second metal with a higher atomic weight in the iodide, a correspondingly greater amount of the iodide of the second metal would be required, in order that an equivalent amount of iodine be present in both iodides.

The specific nature and relative proportions of the oxidising agent, polymer, and acid constituents may be largely dependent upon the iodide constituent, and may be determined by simple calculation, once it has been decided what the required proportion of a particular metal iodide in the iodophor composition is to be.

The composition of the invention is prepared by a simple mixing of the constituents.

However, the sequence in which the constituents are admixed is significant.

The preferred mixing order includes mixing the acid and the polymer together; thereafter adding the iodide thereto with mixing; and finally adding the oxidising agent and any other constituents thereto with mixing. The polymer should be present before the iodide or oxidising agent are in the mixture, as it acts to absorb any iodine liberated by their reacting together, which iodine would otherwise be lost from the powder. Further, by adding the acid constituent before the iodide and oxidising agent are added, discolouration which may be caused by liberation of the iodine, may be avoided.

The invention also extends to a cleaning/ sanitizing solution comprising an iodophor powder composition according to the invention, dissolved in water. In the presence of water, preferably at a pH of below 5, the iodide of the composition is oxidised to iodine by the oxidising agent. In use, therefore, the powder composition of the invention is dissolved in water and diluted to provide a suitable acidic solution in which the concentration of iodine available for cleaning/santizing, is approximately 25 to 100 ppm, and preferably 50 to 100 ppm.

The choice of iodine concentration within this range will depend on the intended usage of the solution. For example, a higher concentration of iodine would be preferable in a solution intended for use in a dairy, brewery, or the like, where the cleaning and sanitizing standards would be higher than for a cooling tower, for example.

The mode of use of the solution will, to some extent, also depend on its intended usage. The solution may be applied by spraying, by circulating it (by pumping, if necessary) through pipes and the like, and/or by immersion of equipment or the like in the soltition.

Spraying may be particularly suitable for dairy and brewery equipment, especially for use in situ cleaning, and/or for cleaning/sanitizing large vessels. Abattoir and butchery equipment may be more suitably treated by immersion in the solution.

Subsequent rinsing with water of surfaces treated with the solution, is optional. In dairies for example, instead of rinsing, the first few litres of milk passed along treated surfaces may serve to flush the solution out of the equipment, etc., and thereafter be discarded.

EXAMPLE An iodophor composition according to the invention was prepared as follows: (a) 90.5% by weight of sulphamic acid was mixed with 5.0% by weight af polyvinylpyrrolidone polymer available from GAF Corporation as PVP K30 Grade; (b) 2.5% by weight of potassium iodide was admixed to the acid/polymer mixture; and (c) finally, 2.0% by weight of sodium perborate (an oxidising agent) was mixed therewith.

Shortly before use, the composition was dissolved in water and diluted to provide a solution in which the available iodine concentration was approximately 80 ppm.

The solution was successfully used to provide a single-stage cleaning process for dairy equipment.

Advantages of the powder iodophor composition include its low foaming property. lodophors based on surface-active agents generally have a strong tendency to foam. The composition of the invention only optionally includes a surfactant and can therefore be prepared in a form that is low-foaming and hence particularly suitable for many industrial cleaning and sanitizing operations, which includes spray-cleaning and/or in situ cleaning, for example for dairy and brewery equipment.

Other advantages of the composition at least as exemplified, include its stability in powder form, even in the presence of the oxidising agent of the composition, and the number and variety of applications for which it appears to be suitable.

Another important advantage of the composition is its optional use in a single-stage cleaning operation. This tends to reduce the time normally required for cleaning/maintenance operations, and tends to increase the periods of effective usage of equipment and the like, and so reduce costs.

Claims (14)

1. An iodophor powder composition which comprises an iodide salt; an oxidising agent which is stable in the dry form, and is capable of releasing iodine from the iodide salt in a solution formed by dispersing the powder composition in water; a polymer capable of forming a polymer-iodine complex and of sub sequently making available a soluble form of the iodine; and an acid.

2. An iodophor powder composition as claimed in claim 1, wherein the iodide is an alkali metal iodide.

3. An iodophor powder composition as claimed in claim 1 or claim 2, wherein the oxidising agent is sodium perborate.

4. An iodophor powder composition as claimed in any one of claims 1 to 3 wherein the polymer is polyvinylpyrrolidone.

5. An iodophor powder composition as claimed in any one of claims 1 to 4 wherein the acid is selected from the group consisting in sulphamic acid, citric acid, and sodium bisulphate.

6. An iodophor powder composition as claimed in any one of claims 1 to 5, which includes a filler material.

7. An iodophor powder composition as claimed in claim 6 wherein the filler material is an inert water soluble salt.

8. An iodophor powder composition as claimed in any one of claims 1 to 7 which includes a surfactant.

9. An iodophor powder composition as claimed in claim 8 in which the surfactant is a liquid, the composition including an absorbent carrier material wherein the liquid surfactant is absorbed.

10. An iodophor powder composition as claimed in claim 1, which includes 0.5 to 1 5% by weight of potassium iodide as the iodide salt, 0.5 to 25% by weight of sodium perborate as the oxidising agent, 0.5 to 30% by weight of polyvinylpyrrolidone as the polymer, and 0.5 to 98.5% by weight of sulphamic acid as the acid.

11. An iodophor powder composition, substantially as herein described and exemplified.

1 2. A cleaning/sanitizing solution comprising an iodophor powder composition as claimed in any one of the preceding claims, dissolved in water.

1 3. A cleaning/sanitizing solution, substantially as herein described and exemplified.

14. A method of preparing an iodophor powder composition as claimed in any one of claims 1 to 11 which includes mixing the acid and the polymer together; thereafter adding the iodide thereto with mixing; and finally adding the oxidising agent and any other constituents thereto with mixing.

1 5. A method of preparing an iodophor powder composition substantially as herein described and exemplified.