GB2218635A

GB2218635A - Moistening solution containing an anti microbial agent

Info

Publication number: GB2218635A
Application number: GB8911480A
Authority: GB
Inventors: Mark L Brachman; Phyllis A Cuming; Vincent D Mannella; Russel E Wellman
Original assignee: Pitney Bowes Inc
Current assignee: Pitney Bowes Inc
Priority date: 1988-05-20
Filing date: 1989-05-18
Publication date: 1989-11-22
Also published as: AU3498689A; DE3916310A1; GB8911480D0

Description

2 k R1 1 - f - C-393 MOISTENING SOLUTION CONTAINING AN ANTI-MICROBIAL

AGENT Liquids, such as water, are often used to moisten adhesives for the purpose of sealing items. Examples of such uses are the sealing of gummed envelopes and moistening of adhesive tapes for the sealing of cartons and the like. In most such sealing applications, tap water is used as a sealing solution. A problem arises with'the use of tap water because in some areas of the country tap water contains impurities which cause the water to "wick up" the water distribution system, and actually spill out of the machine in which it is used.. By "wicking up" is meant that capillary action takes place whereby the water will migrate to undesired locations. In addition, there is a tendency to form slime inside of the vessel or tank holding the water.

This slime is composed primarily of paper and adhesive residues that are: absorbed by and suspended within the water during the sealing operation and algae and bacteria which feed on these residues. Because of the formation of slime, the effectiveness of the sealing system becomes substantially reduced. For example, in a Pitney Bowes Model Series No.

6100 Mailing Machine, a problem arises with the use of tap water in that improper sealing results because the slime tends to inhibit the proper distribution of liquid onto a sealing surface. Depending upon the impurities present, and the response of bacteria thereon, the sealing solution may be applied in excess or be of insufficient quantity. Adding algicides, biocides or the like has been found to be unacceptable because they have a surfactant affect, i.e. they lower the surface tension of the solftion.

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18635 t>, is A sealing solution has beendeveloped which has a sufficiently high surfade tension to eliminate wicking while simultaneously reducing or eliminating the formation of slime in a vessel on system. This is accomplished by adding specific algicIdes or biocides to the solution in such concentrations so as to balance the requirements of surface tension while offering glime protection. A class of algicides or biocides has.been discovered that have good algicide properties with little,effect on the surface tension. This class of anti-microbial agents comprises quaternary ammonium compounds of the benzalkonium chloride type. It has been found that with this particular class of anti- Microbial agents, by using a low concentration one is able to maintain the anti-microbial action while not reducing the surface tension to a level where it becomes detrimental to the system-in which it is used for moistening.

Detailed Description of the Preferred Embodiments

Anti-microbial agents are commercially available which will prevent the formation of slime in water contained in swimming pools by killing or controlling the growth of algae, bacteria, tubercles and the like. The problem with using such anti-microbial agents in a sealing solution is that when they are diluted in-water according to the manufacturer's instructions, the surface tension of the solution falls to lose than 40 dynes/cm.. A surface tension in excess of 55 dynes/cm. is requred to assure a wicking problem will not occur in a.:sealing solution.

It has been discovered that using a low concentration, generally in the range of 2 to 25 ppm active ingredients,,of a quaterary ammonium compound anti-microbial agent of the type having compounds of benzalkonium and a water soluble dye,(and prefeabjy between 5 and 20..ppm in di tilled water will result in a P solution having an acceptable surface tension. This solution prevents wicking, reduces or controls tank slime and provides more uniform sealing.

1 By using a low concentration of a quatanary antimicrobial agent of the type having compounds of benzalkonium, one is able to maintain biocidal action while not reducing the surface tension to a level where it becomes detrimental to the system in which it is used for moistening.

The general formula for an anti-microbial agent that is a quaternaryammonium compound benzalkonium type is:

7 1 Rl -------- 1 1 i i 1 1 N -------- R3 2 -1+ i t i i Where R is an alkyl group Y is a halide, preferably ClX is hydrogen or an alkyl group in the ortho, meta or para position In this structure, one nitrogen bond has an aromatic grofip attached to it and the other three bonds have alkyl groups, Rj, attached thereto. Preferably, at least two of the akkyl groups will be methyl groups.

The addition of small quantities of a water soluble dye has been found useful. It has been found that-the dyes tend to attach themselves to the surfaces of the contaminants in the water, physically preventing the algae or bacteria from feeding on the contaminants. Thus, the combination of the 1 is 1 low quantities of described anti-microbial agents and the water soluble dyes have been most effective in preventing problems normally encountered with water-based moistening systems.

1 EXAMPLE 1

A 10% master solution of a quaternary anti-microbial agent of a type having a quaternary ammonium compound of the benzalkonium type in distilled water was used to prepare solutions having concentrations of 2, 5,10,15,20, and 25 ppm. Even at 25 ppm, surface tension was significantly above the 55 dynes/cm minimum. A dye solution, having a concentration of 0.05%, was added to 500 ml of the anti-microbial agent solutions, at all concentrations, after the initial surface tension measurements were made. Firstly, 2 ml of the dye solution was added.. After the surface tension was measured, 2 mils additional dye solution was added before the final surface tension measurement. Surface tension dropped little with increased concentration and even the 25 ppm antimicrobial agent with 4 ppm Cartesol Turquoise KRL dye (basic blue 140) available from Sandoz Chemicals Corp., Charlotte, N. C. concentration, the surface tension was still 58 dynes/cm. The quaternary anti-microbial agent in this particular Example 1 was a 40% solution of a mixture of 80% methyl dodecyl benzyl, trimethyl ammonium chloride and 20% methyl dodecyl xylylene bis (methyl- )trimethyl ammonium chloride. The solutions had stable surface tension over time and exhibited good resistance to slime formation.

The surface tensions achieved with the above solutions were tesed and the results were as follows:

Ir k Anti-microbial Agent Aquamaid Surfacetension dynes/c PPK No dye 2ppm dye 4 ppm dye 2 70.4 64.8 5 63.0 57.2 - 62.9 60.1 60.6 is 64.8 63.2 62.2 62.3 61.2 59.9 58.8 60.2 58.0 is EXAMPLE 2

Solutions were made having 2,5,10,15,20, and 25 ppm active ingredient using as the anti-microbial agent a 10% solution of alkyl C12, 14,16) dimethyl benzyl ammonium chloride. Surface tension was measured on solutions having no dye, 2 ppm, and 4 ppm Cartesol Turquoise KRL dye at every concentration. At all concentrations of dye and algicide surface tension was above 60 dynes/cm. The solutions had good stable surface tensions and good resistance to slime formation.

The surface tensions achieved with the above solutions were tested and the results were as follows:

Pomeco Solution ppm algicide No dye 2 ppm dye 4 ppm dye 2 64.8 62.7 60.8 66.4 64.6 63.5 10--- 68.7 67.6 65.1 65.3 67.0 62.5 61.8 67.0 65.3 67.7 65.7 65.3 1( p EXAMPLE 3

A 0.24 mil solution of the anti-microbial agent of Example 2, 10% concentration as supplied, and 80 ml of a 0.05% Cartesol Turquoise KRL (which is basic blue 140) solution was mixed into 4 liters of distilled water to make a 6 ppm anti microbial agent, 10 ppm dye solution. Surface tension was 63.5 dynes/cm. Ten ounces was saved for observation and the remainder was tested in mailing machines. The sealing fluid was tested for a three month period and was found to work well. No wicking problem was encountered and slime formation was inhibited.

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Claims

CIAIMS

1. A method of formulating an anti-microbial solution, comprising: adding as an anti-microbial agent 2 to 25 parts per million of a quaternary ammonium compound of the benzalkonium chloride type to water.

2. The method of claim 1 including the step of adding to said solution 2 to 25 parts per million of a water soluble dye.

3. The method of claim 2 wherein said anti-microbial agent has the general formula:

1 i i i Where R is a n alkyl group Y is a halide, preferably ClX is hydrogen or alkyl group in the ortho, meta or para position k 1 c

4. The nethod of claim 3 including the step of selecting as the quaternary anti-microbial agent a solution of a mixture of methyl dodecyl benzyl trimethyl ammonium chloride and methyl dodecyl xylylene bis-(methyl-)trimethyl ammonium chloride.

5. The method of claim 3 including the step of selecting as a antimicrobial agent a solution of alkyl (C12.14.16) dimethyl benzyl ammonium chloride.

6. An anti-microbial solution, comprising: water, and an anti-microbial agent 2 to 25 parts per million of a quarternary ammonium compound of the benzalkonium chloride type.

7. The solution of claim 6 including 2 to 25 parts per million of a water soluble dye.

8. The solution of claim 7 wherein said anti-microbial agent has the general formula:

-l t 1 1 i R1 -------- N 4 1 1 i 1 1 i 1 1 1 1 2 1 - 1 3 1 v 1 1 1 1 1 2 t..

X where R is an alkyl group Y is a halide, preferably Cl- I X is-hydrogen or an alkyl group in the ortho, meta or para position.

9. The solution of claim 7 wherein sa-ici quaternary antimicrobial agent is-a mixturq of methyl dodecyl benzyl trimethyl ammonium chloride and methyl dodecyl xylylene bis (methyl-)trimethyl ammontm chloride.

10. The solution of claim 7 wherein said anti-microbial agent is a solution of alkyl (C12,14,16) dimethyl benzyl ammoniom chloride.

11. An antri-microbial solution substantially as herein described.

12. A method of making an anti-iiii.crol:ial solution including a die substantially as herein described 1 1 Published 1989 at The Patent Office, State House, 86,f7l High Holborn. LondonWClR4TP. Further copies maybe obtaanedfroin The Patent Office. Sales Branch, St Maxy Cray, Orpington, Kent BR5 3RD, Printed by Multiplex techniques ltd, St Mary Cray, Kent, Con. 1187