US3505237A - Steam iron additive composition - Google Patents

Description

United States Patent Ofilice 3,505,237 Patented Apr. 7, 1970 3,505,237 STEAM IRON ADDITIV'E COMPOSITION Roger C. Steinhauer, Park Forest, Ill., assignor to Armour and Company, Chicago, 11]., a corporation of Delaware No Drawing. Filed Mar. 6, 1967, Ser. No. 620,655 Int. Cl. C23f 14/02; D06f 75/14 US. Cl. 252-180 9 Claims ABSTRACT OF THE DISCLOSURE A steam promoting composition comprising as essential active ingredients a polyethylene glycol having a molecular weight of from 120 to 1000 and a siloxanepolyoxyalkylene block copolymer having molecular weight of from 400 to 600.

BACKGROUND OF THE INVENTION My invention pertains to an aqueous polyethylene glycol and silicone fluid composition which may be added to the water in the reservoir of steam producing apparatus such as steam irons to enhance steam production and to change the character of hard mineral scales within such apparatus.

Steam irons generally comprise an electrically heat controlled sole plate and a reservoir for water which is heated in the iron and released therefrom as steam through holes in the sole plate. The water is either heated to steam in the reservoir; or, in the more popular style of steam iron commonly called the flash boiler type, the water is released from the reservoir through an actuated needle valve in a drop-wise fashion, and when each drop of water comes into contact with the hot sole plate it flashes to steam and escapes through the holes in the sole plate.

Problems encountered by the consumer in the use of steam irons include sputtering, leaking and dripping of hot water that has not flashed to steam, insufficient production of steam due to bubble or foam formation of the water and other factors, and clogging of the needle valve vent due to hard Water scale build-up. Hard water, containing calcium, magnesium and other minerals, can cause very serious scale problems. Its use in steam irons shortens the life of the iron considerably and generally steam iron manufacturers warn against using it in their products. The scale that is formed from hard Water deposits is very hard and brittle; once it has formed, it is most difficult to remove.

Polyethylene glycol esters prepared from polyethylene glycols having molecular weights of from 400 to 1000 have been used in mixture with hydrocarbon soluble organopolysiloxane for defoaming latex paints and adhesive materials (United States Patent 2,843,551), Also, polyoxyalkylene glycols having a molecular weight of from 1000 to 11,500 have been used in a method for inhibiting foam formation in boiler water, under super-atmospheric temperature and pressure conditions, with a high concentration of total dissolved solids in the water (United States Patent 2,846,404).

SUMMARY OF THE INVENTION My invention relates to a new composition of matter, said composition possessing excellent utility for increasing steam production in steam promoting apparatus. More particularly it relates to a composition which may be added to the water in a steam iron for purposes of promoting steam production and of changing the character of hard water scale build-up.

Therefore, it is an object of this invention to provide a new composition of matter, said composition having particular utility in steam producing apparatus. It is an object of this invention to provide a composition to enhance production of steam from water, and in particular, the water in steam irons. Another object of this invention is to produce extra steam in a steam iron Without causing spitting or dripping. A further object of this invention is to inhibit needle valve clogging when hard water is used in steam irons by changing the nature of the scale build-up from a hard brittle thick coating to a soft fuzzy thinner deposit which is easier to remove. Still another object of this invention is to make ironing easier by imparting a lubricating film to the fabric and reducing static electricity charge build-up on the fabric. It is still another object of this invention to impart a supple, wrinkle resistant finish to the ironed fabric. A further object of this invention is to impart a fresh clean odor to the ironed fabric. Other objects and advantages and a fuller understanding of my invention will become more apparent from the ensuing description and examples.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In a specific embodiment, my invention may be exemplified by the composition to be added to the water in a steam iron comprising, in combination, a stable oil in water emulsion of (1) a polyethylene glycol having a molecular weight of from about to 1000, (2) a s'iloxane -polyoxyethylene block copolymer having a molecular weight of from about 400 to 600, (3) an aqueous formaldehyde solution, (4) a relatively nonvolatile perfume, (5) a relatively nonvolatile dye and (6) distilled or demineralized water. The polyethylene glycol and the siloxane-polyoxyethylene block copolymer are essential active ingredients of my invention; the other components may be added for a preferred composition accomplishing the above and other objects. About one part of the composition by volume may be added to about nine parts by volume of either tap Water, demineralized or distilled water for use in steam irons.

The novel composition of the present invention contains a polyethylene glycol as one essential component. The polyethylene glycols suitable for use in the practice of this invention are characterized by a plurality of ether linkages and two terminal hydroxyl groups, and have a molecular weight of from about 120 to 1000. I prefer to use polyethylene glycols having a molecular weight of from about to about 600. Especially desirable polyethylene glycols are heat stable, less hygroscopic and afford better lubricity than simple glycols and glycerine, have a boiling point of approximately 280" to 310 F., and a molecular weight of from about to about 210. The amount of the polyethylene glycol in the composition may vary over wide ranges depending on the use ratio of the composition in the water to be steamed. A preferred concentration is from about 7% to about 10% by volume in a composition to be used in a steam iron at a rate of one part of composition by volume to nine parts by volume of Water.

The composition of the present invention contains as a second essential ingredient a siloxane-polyoxyalkylene block copolymer, or silicone fluid. Silicone fluids suitable for use in the practice of this invention are organosilicone fluids with surface active properties, having a molecular weight of from 400 to 600, which embody the properties of both organic and silicone oils and impart good lubrication and anti-wear properties. Silicone fluids having a molecular weight of from about 500 to about 550 are preferred. The deforming properties of the silicone fluids useful in my invention tend to inhibit bubble formation thereby enhancing steam liberation. Concentration of the useful silicone fluids in my composition may vary from 0.01% to 10%, again depending upon use ratio of the composition in the water. A preferred concentration is from about 0.05% to about 1.5% concentration in a :omposition to be used in a steam iron at a rate of one part by volume of composition to nine parts by volume of water.

The proportions of the two essential ingredients are not critical. However, I generally prefer proportions by volume of the glycol to the silicone fluid ranging from about 1:1 to about 30:1 to accomplish the objects of my invention.

The third component of my composition exemplified in the above specific embodiment is an aqueous solution of formaldehyde. Such solution is preferably at 36% active formalin solution but may be any other like formaldehyde yielding material. Its role in the composition is to serve as a preservative. It is not essential that formaldehyde or like substance be present in the composition, but its presence is desirable due to the fact that aqueous solutions of polyethylene glycol serve as a good medium for the growth of mold. Therefore, it is useful to incorporate in the composition a concentration of from about 0.05% to 1.0% of a 36% active formalin solution. A preferred concentration is from 0.1% to 0.2%.

The remaining components of the composition exemplified in the specific embodiment hereinabove are a perfume and a dye. These are optional components, and if they are used at all it is preferred that they be non-volatile and that their amounts be kept to an absolute minimum.

The concentration of my composition in the water to be steamed may vary over a wide range. I may use the composition as is or in a dilution ratio. A dilution ratio ranging from about 1:1 to about 100:1 is generally desirable when the composition is used in steam irons. About 7:1 to about 10:1 is preferred. The concentration is not critical and concentrations outside these ranges may be used, but without substantial enhanced effect.

Using my com-position and hard water in steam irons does not substantially decrease scale build-up. However, the character of the scale is changed to a softer, looser, granular residue which does not cause needle valve clogging as readily as hard water alone. Apparently, these soft granules are to an extent flushed off by water released from the reservoir, thereby extending the useful life of the iron.

In order to more fully describe the nature of my composition and the manner in which it may be used, the following illustrative specific examples are provided.

EXAMPLE I Any compound added to the water in a steam iron to increase steam production must, in addition, not cause clogging of the needle valve vent or the steam vents. Nor may such a compound leave appreciable residual deposits when dilute aqueous solutions containing the com-pound are evaporated from a hot surface. In accord with these criteria, a number of polyethylene glycols and silicone fluids were evaluated by the following procedure:

A thermostatically controlled hot plate was positioned on the base of a ring stand and two disposable aluminum weighing dishes were placed on the hot plate. Two 50 ml. burets were clamped to the ring stand so that each was positioned over an aluminum dish, and the burets were,

charged with ml. of an aqueous solution of the test compound in one buret and 25 ml. of water in the other. In one phase of this evaluation distilled water was used in order to determine the residual properties of the compounds in the absence of hard water salts. In the other phase of this evaluation, tap water having a hardness of 135 ppm. was used in the solution and compared to a tap water only control. The solutions contained an active concentration of 0.5% of the compounds being evaluated. The hot plate was adjusted to maintain the aluminum dishes at a temperature of 350 F. and the contents were allowed to drip into the hot aluminum dishes at a rate that would prevent pooling of the liquid. During this operation the steam producing properties of the solutions were visually observed and recorded. After the burets had emptied and all volatiles had evaporated from the dishes, the dishes were weighed. The amount of any residue was recorded in grams and the percent of non-volatile residue for the solutions were compared to the water controls. Steaming properties and residual deposit characteristics for the compounds evaluated in distilled water are set forth in Table I. TableII shows the corresponding data for tap water.

From Table I it may be seen that the polyethylene glycols tested in general increase steam and leave little or no residual deposits. Most of the silicones evaluated leave appreciable deposits and have no effect on steam production. Combining the silicone with the polyethylene glycol results in a composition that increases steam production without leaving a substantial residue. In tap water (Table II) the polyethylene glycols alone produced more steam but had little effect on hard water scale build-up. Incorporation of Silicone L520 with the lower molecular weight polyethylene glycol did change the nature of the hard water deposits.

TABLE 1'.

[0.5% solutions in distilled water] 0.5% Solution Residue twt.) Add ltive Steam (gms.) Percent Properties None (control) 25 0 Carhowax 200... Increased.-.. 25 0. 23 Dry. Carbowax 600 do 25 0. 47 Dry, sticky. Carbowax 1000.. 25 0.77 81., oily. Carbowax (i000 do 25 1.03 Oily. Silicone L-7l3. No effect 25 0. Waxy. Silicone L520 Slight increase. 25 1. 20 Do. Silicone L522 No effect 25 1. 27 Charred. Silicone L527 d 25 1.31 Do. Silicone L530 do 25 1 29 Do. Silicone L5310 do 25 1. 14 Waxy. Silicone XFI-lOOl do 25 1. 43 Charred. Silicone XF-1007 do 25 1. 56 Do. 3 to 1 Silicone L- Increased. 25 0. 71 Oily.

520 and Garbowax 600. 9 to 1 Carbowax do 25 0. 49 Dry.

200 and Silicone L520.

TABLE II [0.5% solutions in tap Water p.p.m. hardness)] 0.5% Solution Residue (\vt.) Additive Steam (gms.) Percent Properties None (control) 25 0 Carbowax 200" Increased... 25 Dry. Carbowax 600... do 2b 0. 44 Dry, sticky. Carbowax 6000 do 25 1.03 Oi and salt ep. Silicone L520 No eiTect 25 1 12 Waxy. 3 to 1 Silicone L520 Increased 25 0. 71 Charred and Garbowax 600. film. 9 to 1 Oarbowax 200 .-..rlo 25 0. 49 No charring.

and Silicone L520.

EXAMPLE II Steam production rates were determined for my com position in tap water and in distilled by the following procedure. The water reservoir of a flash boiler type of steam iron was filled with distilled water, the filled iron was weighed on a balance scale and the weight recorded. With the iron still resting upon the balance, steaming was started and the weight loss was periodically recorded until all water had steamed out. This was repeated for several runs and the average weight loss in grams per minute (g./m.) was recorded. The procedure was repeated adding, to 9 parts of distilled water, 1 part of the following composition:

Percent Carbowax 200 8.9 Silicone L520 1.0 Formalin (36%) 0.15 Perfume 0.10 Distilled water 89.85

TABLE III Steaming Rate Distilled Water aging upon it. At that time, steam rates were again determined in distilled water using the procedure of Example II. The data for 3 runs is set forth in Table IV.

moting apparatus comprising from 0.05% to 50% concentration of a polyethylene glycol having a molecular weight of from about 120 to 1000, and from 0.01%

to of a siloxane-polyoxyethylene block copolymer having a molecular weight of from 400 to 600 and the balance of the composition being water.

2. The composition of claim 1 in which the molecular weight of said glycol is from about 175 to about 600.

3. The composition of claim 1 in which the molecular Weight of said glycol is from about 190 to about 210.

4. The composition of claim 1 in which the molecular weight of said copolymer is from about 500 to about 550.

5. The composition of claim 1 in which the concentration of said glycol is from about 7% to about 10%.

6. The composition of claim 1 in which the contration of said copolymer is from about 0.05 to about 1.5%.

7. The composition of claim 1 in which the composition includes from 0.05% to 1% of a 36 active formalin solution.

TAB LE IV.--STEAM P ROD UC TION Distilled Water Only, Grams Lost (min).

Distilled Water With Aged Sample,

Grams Lost (min) Minutes 4 s 12 16 20 24 2s 32 36 Minutes 4 s 12 16 20 Initial Weight: Initial weight:

02 94 118 130 153 170 105 217 Avg 54 106 154 102 21s EXAMPLE IV 8. The composition of claim 1 added to said water at It has been found that flash-boiler" style steam irons clog at the needle valve seat after continuously steaming approximately 3 to 4 gallons of tap Water having a hardness of 37 grains per gallon.

Using 3.4 cups of the composition of Example II per gallon of tap water having a hardness of 37 grains, I evaluated the composition for the length of time it could be continuously steamed from this style steam iron before clogging the iron at the needle valve seat. The water was siphoned continuously into the iron reservoir and allowed to steam until the iron clogged. I found that the iron did not clog until after 6.4 gallons had been steamed. Repeating the evaluation using the same composition addition rate and the same composition but without the perfume component, 7.1 gallons of this water steamed through the iron before it clogged.

I claim:

1. A steam promoting stable oil in water emulsion composition to be added to the water of a steam proa dilution ratio ranging from about 1:1 to about 100:1.

9. The composition of claim 1 added to said water at a dilution ratio ranging from about 7:1 to about 10:1.

References Cited UNITED STATES PATENTS 2,467,177 4/1949 Zimmer 252-321 2,843,551 7/1958 Leonard et a1. 252321 2,846,404 8/ 1958 Johnson 252-321 2,990,377 6/1961 May 252--312 3,359,212 12/1967 Bailey 2523 12 LEON D. ROSDOL, Primary Examiner I. GLUCK, Assistant Examiner