CA1119915A

CA1119915A - Carbonated cleaning solution

Info

Publication number: CA1119915A
Application number: CA000330832A
Authority: CA
Inventors: Robert D. Harris
Original assignee: Harris Research Inc
Current assignee: Harris Research Inc
Priority date: 1978-07-03
Filing date: 1979-06-29
Publication date: 1982-03-16
Also published as: US4219333A; US4219333B1

Abstract

CARBONATED CLEANING SOLUTION

ABSTRACT

An aqueous cleaning composition containing 0.1-5 percent of a detergent which may be nonionic or anionic, 0-1 percent of one or more alkaline builder salts and 0-5 percent of a volatile organic solvent wherein the cleaning solution is carbonated with carbon dioxide and maintained at a pressure of from about 1 to 10 atmospheres.

Description

BACKGROUND OF TH~ INVENTION

This invention relates to carbonated cleaning solutions. More particularly, this invention rela~es to carbonated cleaning solutions having the ab:ility to pene-trate textile fibers and dissolve and/or liEt both inor-ganic and organic materi.als ~rorn the -:Eibers.
There are myriad types oE cleaning solutions on the market for cleaning textile Eibers such as carpets. Various processes such as dry cleaning, steam cleaning and shampooing take advantage oE diEferent types and kinds oE cleaning solutions. Volatile petroleum based hydrocarbons are used in dry cleaning processes. Steam cleaning and shampooing may utilize one or more o~ the many soaps and s~nthetic detergents in an aqueous solution. Detergents may be clas-siEied as regular, industrual or high s-trength and are categorized as cationic, anionic or nonionic.
Each type o~ cleaning solution is Eormulated to loosen and disperse the soil ~rorn the textile Eibers either physically or by chemical reaction. The soil can then be solubilized or suspended in such a manner that it can be removed ~rom the ~ibers being cleaned.
Typically, soils reeer to both organic and inorganic matter that comes in contact with the :eibers and adheres thereto. Dirt particles, greases, oils, -eoods, cosmetics and paints are representative oE the rnaterials hereinaEter ;~
re~erred to as "soils" that work their way onto and into various textile :Eibers.

- - . .

o- ~

Various types O:e :I'ibers are used in making carpe-ts.
Wool is by ear the most prevalent na-tural materia] used although a certain amount of co-tton is also employed in washable carpet materials. Synthetic ~'ibers may be made of a variety of difeerent chemicals. Polyamide ~ibers such as the nylons are commonly used as are polyesters such as esters O:e acrylic and methacrylic acids.
Some types of fibers are more absorbent to one particular type o~ soil than another. Soils in the form of particula-te matter lodge at the base of the carpet, for e~ample, and are vary difficult to remove as by vacuuming or treatment with a cleaning solution.
These particles are a cause ol' excessive carpet wear since they tend to damage fibers when pressure is placed between the par-ticle and the fiber as by someone walking over a carpet or by a piece O:e furniture placed on the carpet. O-ther soils such as oils and fats adhere -to -the fibers and work their way between :eiber strands. O-ther types o-~ soils are absorbed by such fa-ts and oils causing the carpets to stain or look dirty.
One o:E the basic drawbacks -to many cleaning composi-tions is that, while apparently 'loosening and dispersing the soil, they fail to pick up and retain the so:il and it is redeposited as the cleaning so]ution is removed from th0 sur:eace being clealled. :~t is also dieeicult -to remove all o~ the deter-gent from the fiber surface such as in carpets, even when rinsing with large amounts of water or steam. ~s a r-esult the carpet eibers become tacky from the film of de-tergent on them. This attracts and retains soil so the net effect is a cleaned carpet that will soil more easily after a cleaning than prior thereto.
Various methods have been proposed to prevent carpet from resoiling. Ernbrittling agents have been used in cleaning cornpositions to embrittle the surfactant and render the fiber surface non-tacky. Alumina, in various forms, has been proposed as an anti-soil reagent as have certain polymers such as carboxy methyl cellulose. While somewhat successful, there still remains a need for a cleaning composition and method which will efficiently 10 clean and effectively remove soil from textile fibers without causing a resoiling problem.
Many cleaning solutions are quite alkaline and darnage to fibers may occur when using too strong a detergent concentration.
Also the large amounts of water required in most carpet clean;ng operations cause the carpet and often the pad under the carpet to become saturated ~ith water. Long periods of time are required for drying. Portions of the carpet which are inadequately dried may result in rotting or decomposit;on of the fibers.

OBJECTS AND SUMMARY OF THE lNVENTION

It is an object of the present invention to provide a cleaning composition which effectively and efficiently rer~oves soil from textile fibers which also acts as an anti-soil reagent.
Lt is a further object of this invcntion to provide a novel cleaning CompoBition which rapidly pcnetrates textile fibers removing the soil thcrerom with a lifting action.
Another object of the invention ;s to provide a cleanirlg composition which rapidly penetrates textile fibers rernovirlg the soil therefrom with a lifting action.
Another object of the invention is to provide a cleaning composition which causes no damage to textile fibers and which can be rapidly removed therefrom without leaving a residue thereon .
A still further object of this inventic)n is to provide a method of cleaning textile fibers utilizing a minimal amount of an aqueous cleaning solution.
Yet another object of this invention is t:o provide a method of cleaning textile fibers which is fast drying and which does not leave a chemical residuc upon thc fibers when dried.
A different object of this inverltion is to provide a method of cleaning textile fibers ~vith a non-toxic, non-imflammable cleaning solution which rapidly penetrates such fibers and which is easily removed from such fibers having a soil repellant effect thereon .
These and other objects are accornplished by means of an aqueous cleaning composition comprising 0.1-5 percent by weight of an anionic or nonionic detergent, 0-1 percent by weight of one or more alkaline builder salts and 0-5 percent by weight of ~ volatile organic solvent wherein the solution is 20 carbonated with carbon dioxide and maintained at a pressure of from about 1 to 10 atmospheres. A method of utiliæing the carbolELted cleaning conlposition for cleaning carpets, upholstery and other textile fibers by applying the cleaning solution to the fibers is also part of tllis invention.

DETAILED DESCRIPI`ION OF T~IE INVEN'rION

Suitablc dctergents for use in the present invcntion comprise primariLy any of the nonionic and anionic surfactants.
The nonionic detergents seern to be preferable for purposes of carbonation. While typical nonionic and anionic detergents are 30 enumerated herein it is to be emphasi~cd that there are literally ~1~99~

thousand9 of detergent mixtures or combinations and the recital of a representative number is not meant to be a limitation as to the scope of the invention. Moreover, two or more of the formulations listed could be used in combination as ~Nell as separately .
One suitable class of nonionic detergents is the alkyl phenol-ethylene oxide condensates having the formula:

R ~~ --(C~12C~120)nCH2CH20H

wherein R is an alkyl group having from nine to twelve carbon 10 atoms and n is an integer of from eight to fourteen. Typical examples include dodecyl phenol condensed with an average of ten moles of ethylene o~ide sold commercially as "Sterox DJ", nonyl phenol condensed with an average of nine or ten moles of ethylene oxide sold commercially as "Triton N101", "Igepal C0-630" and Tergitol NPX" and dodecyl phenol condensed with an average of fifteen moles of ethylene oxide.
Another nonionic detergent class are the polyoxyalkylene alkanols having the empirical formula:

" HO (C2H~O)a(C3H60)b(C2H4 )c 20 wherein b is an integer from 26 to 30 and a plus c is an integer such that the moleculc contains from O percent to 20 percent of ethylene oxide. Typical cxamplcs thercof include "Pluronic L-61" where b is an integer frorrl 26 to 30 and a plus c iB an integer such that the molecule contains frorn 10 percent to 20 percent of ethylene oxide and "Pluronic "L,-60" where b iB an integer from 26 to 30 and a plu9 C iS zero so that the molecule is all polyoxypropylene. These detergents are low sudsing.

.Another class of nonionic detergents include condensation products of a fatty alcohol with ethylene oxide to produce cor~pounds having the formula:
R~ O--(C2H4O)nH
wherein R i5 an alkyl group containing from 10 to 20 carbon atoms and i5 preferably a straight chain alkyl group, and n is an integer of from 6 to 14. The alkyl content of these compo-sitions can vary from 10 to 20 carbon atom6 within the same mixture due to methods of manufacture. Thelefore, the detergent will 10 usually be one containing mixed alkyl groups. The same is true for the ethylene oxide groups and thus, ethylene oxide chains having different lengths will be produced within the same mixture.
Typical products include Neodol 25-7 and Neodol 45-11 (Shell Chernical Company) wherein R is mixed alkyl from 12 to 15 and 14 and 15 carbon atoms respectively and n is an average of 11 and Plurofac B-26(Wyandotte Chemical Co. ) which is a linear alcohol reacted with a mixture of ethylene and propylene oxides.
Exemplar)r anionic materials are the water soluble, straight and branched chain alkylarly sulfonates, particularly 20 the alkyl benxene sulfonates, wherein the allcyl group contains from about 8 to 15 carbon atoms, the lower aryl or hydrotropic sulfonates such as sodiurm zylene sulfonate; the olefin sulfonates, such as those produced by sulfonating a C10 to C20 straight-chained-olefin; hydroxy C10 to C24 alkyl sulfonates; water-soluble alkyl disulfollates containing frorn about 10 to 24 carbon atoms, the normal and secondary hil3her alkyl detergents; particular.Ly those having about 8 to 15 carbon atoms in the alkyl residue such as lauryl or coconut fatty alcohol sulfate; sulfuric acid esters of polyhydric alcohols partially esterified with higher fatty acids ~,l"i ~ ~
9~5 such as coconut oil, monoglyceride, monosulfate, coconut~
ethanolamide sulfate, lauric acid amide or taurine and the like;
the various soaps or salts of fatty acids containing from 8 to 22, particularly 10 to 18, carbon atoms, such as the sodium, potassium, ammonium and lower alkanol-amine, particularly mono-, di-and tri-ethanolamine salts o fatty acids such as stearic acid, oleic acid, coconut fatty acid, fatty acicls derived from palm oil~ soybean oil, tallow and the like. Particularly preferred anionic surfactants include the fatty alcohol and ether alcohol sulfates and the sodium salts of fatty acids containing from about 10 to 18 carbon atoms.
The composition of the present invention also includes an anionic detergent which is a sulfated ethoxylated higher fatty alcohol of the formula RO~C2H40) S03M wherein R is a fatty alkyl of from 10 to 20 carbon atoms, n is from 2 to 6, and M is a solubilizing salt-forming cation such as an alkali metal, ammonium, lower alkylamino or lower alkanolamino. The fatty alkyl may be terminally joined to the polyxyethylene chain, which, of course, is terminally joined to the sulfur-forming sulfate group .
The ethylene oxide content of the anionic detergent is such that n is from 2 to 6 and is preferabl~ from 2 to 4, generally averaging from 3, especially when R is a mixed lZ to 15 carbon atorn alkyl. To maintain a desired hyclrophilic-lipophilic balance, when the earbon content of the alkyl chain is in the lower portion of the 10 to 20 range, the ethylene oxide content might be recluced so that n is about 2, whereas when R i9 of 16 to 18 earbon atoms, n may be from 4 to 6. The salt forming cation rnay be any suitable solubilizing metal or radical but will most frequently be alkali metal or ammoniurn. If alkylamine or lower alkanolamine groups are present, alkyls and alkanols thereof will usually contain one to four carbon atoms and the amines and alkanolamines may be mono-, di or tri-substituted, e.g., monoethanolamine, diisopropanbolamine, tri-methylamine.
One suitable anionic composition is available fr~m Shell Chemical Company and is identified by them as Neodol 25~3S, the sodium saltJ normally sold as a 60 percent active material, including about 40 percent of aqueous solvent medium of which a minor proportion is ethanol. Although Neodol 25-3S is sodium salt, the potassium salt and other suitable soluble salts may also be used either in partial or complete substitution for that of s odium .
Examples of the higher alcohol polyethenoxy sulfates which may be used as the anionic constituent of the present composition include: mixed C12 15 normal prirnary alkyl triethenoxy sulfate, sodium salt; myristyl trlethenoxy sulfate, potassiurn salt; n-decyl diethenoxy sulfate, diethanolamine salt, lauryl diethenoxy sulfate ammoni~lm salt; palmityl tetraethenoxy sulfate, sodium salt;
mixed C14 15 normal primary alkyl mixed tri- and tetra-ethenoxy `~
sulfate, sodium salt; stearyl pantaethenoxy sulfate, trimethylamine il salt and mixed C10_18 normal alkyl triethenoxy sulfate, potassium , salt. Minor proportions of the corresponding branched chain li and medially alkoxylated compound such as those described above but modified to have ethoxylation at a rneclial carbon atom, e . g., one loc~Lted four carbons from thc end of the chain, may be employed ¦
but thc carbon atom content of the higher alkyl will be the same.
Similarly, the joinder of a normal alkyl may bc at a seconclary carbon one or two carbon atoms removed frorn the end of the chain. Most commercially available laundry detergents are believed to be anionic alkyl aryl sulfonates.
The alkaline builder salts which can be employed in the cleaning compositions include alkali metal silicates, phosphates, carbonates and borates and, to a lesser extent, alkali metal hydroxides. Typical of the alkaline builder salts are sodium orthosilicatc, sodium mctasilicatc, sodium carbonate, trisodiurr phosphate, sodium tripolyphosphate, tetrasodiurn pyrophosphate, socliun~ hexametaphosphate and sodium tetraborate. Mixtures of two or more of the alkaline builder salts are often used advantageously to impart desired properties to detergent formulation such as pH and corrosion control.
A volatile hydrocarbon solvcnt rnay be used to aid in 10 dissolving organic soils and prornote drying. Typical classes of solvents include halogenated hydrocarbons, lower alkyl ethers containing one or two ether linkages and unsubstituted hydrocarbons all of which have a boiling point below lOO C.
The halogenated hydrocarbon solvents having the requisite volatility and chemical stability are the polyhalogenated lower alkcyl materials having from one to five carbon atoms and preferably from one to three carbon atoms. Typical of such materials are 1, l-dichloro ethane, 1, 2-dichloro ethane, dichloro methane, dibromo methane, 1, l-dichloro ethylene, 1, 2-dichloro ethylene, 20 1, l-dichloro propane, 1, 2-dichloro propane, 2, 2-dichloro propane, 1, 1-dichloro propylene-l, 1, 2-dichloro propylene-l, 1, 2-dichloro propylene-2, chloroform, 1, 1, l-trichloro ethane, trichloro-ethylene and carbon tetrachloride.
Thc lower allcyl cthers may have allcyl group~ ranging frorn one to four carbon atoms and h.lvc a single ether linkage.
Tyyical of such ethers are cliethyl ct11cr, clipropyl ether, diiso-propyl ether, rmethylpropylethcr, cthylpropyl ether, methylbutyl ether, ethylbutyl ether, diallyl ether, allylethyl ether, allypropyl ether and allylisopropyl ether.
Alkyl ethers having multiple ether linkages or free hydroxyl groups which are water sol~lble are wetting agents and may bc added to assist the detergcnt action, especially of the nonionic surfactants. Typical of such wetting agents are the dialkyl ethers of` glycol such as the diethyl ether of ethylene glyc ol .
Unsubstituted hydrocarbon solvents such as benzene, heptane and hexane may be used but are highly flammable and are therefore less preferred.
Other additives commonly found in comrnercial detergent compositions may also be utilized without departing from the 10 scope of this invention. Thesc includc foaming agents, bleaches, optical brighteners, fillers, plastici~ers, dyes, fragrances, anti-soil reagents, antiseptics, germicides ancl the like.
Essential to the proper functioning of the aqueous cleaning compositions is the carbonation. It is believed that the carbonation of the aqueous cleaning solutions described herein is the key to rapid, thorough cleaning of carpets and the like without leaving a detergent residue on the textile fiber. Obviously, carbonation of aqueous solutions is minimal at atmospheric pressure as is exhibited by opening a container of a carbonated beverage and 20 letting it stand. The carbonation soon leaves the beverage in the container. The same is true with cleaning compositions.
Therefore it is preferred that carbonation be carried out under a gauge pressure of from 1 to 10 atmospheres or from about 14.7 to 147 psig. Higher pressures may be utilizecl but are not considered necessary.
While chen1ical carbonation is possiblc by rnixing such reagents as soclium bicarbon~te ancl an acid together in the cleaning solution it is preferred to inject carbon clioxide directly into the cleaning solution in a pressure contailler such as a sprayer.
30 The cleaning solution is prepared and diluted to the proper ",~ e~ ~

concentration in a vessel or container capable of being maintained under press~2re. The amo~lnt or degree of carbonation will be a function of the pressure in the container and the amount of carbon dioxide supplied to the container. Preferably the carbon dioxide is Ied from a pressurized cylinder directly into a spray tank which is put under pressure. If desired solid carbon dioxide, i. e. dry ice, may be used as a source of carbonation.
An advantage of using a pressurized cylinder is that the C~2 feed can be controlled and monitorecl.
Carbonation of the cleaning solution and application of such solution to a carpet or other fiberous r-naterials is carried out at ambient temperatures. It is evident that at higher pressures the degree of carbonation will be greater than at lower pressures.
Prior to carbonation the cleaning solution will have an alkaline pH and is preferably buffered at a pH of between about 9 and 12 by standard acid-base buffering agents. At an alkaline pH the cleaning solution may adversely affect certain textile fibers. However, upon carbonation, the pH of the cleaning solution is lowered by the formatioll of carbonic acicl such 20 that the pH, at the time the carbonatecl solution is applied to the textile fiber, is essentially ne~ltral.
The carbonated cleaning solution breaks into myriad tiny effervescent white foam bubbles whell applied to a carpet or similar material and rapidly penetrates the textile fibers.
Comparable tests with both urlcarbonate(l and carbonated cleaning solutions have den~onstrated that the carbonated so1utions penetrate and clean a tightly woven carpet approximately 50 percent faster and better than the uncarbol-ated cleaner. Moreover carpets, when cleaned with tlle carbonated solution do not resoil 30 as rapidly as carpets cleaned with uncarbonated solutions.

While not fully understood and not wanting to be limited to any theory, it is believed that the carbonation of the aqueous solution results in a rapid lifting action due to the rnultitude of effervescent bubbles. The soil is stripped off the textile fibers by chemical or physical means ancl is lifted to the surface by the buibbles. Dirt particles can be easily removed from the top of the carpet or other textile surface in a conventional manner.
The effervescent bubbles promote rapid drying of the fibers and evaporation of the cleaning solution along with clissolved soils 10 into the atmosphere. Because the CO2 bubbles promote rapid drying, little or no cleaning solution is left on the fibers thereby imparting a soil resistant quality to the cleaned fibers. It is also believed that the bubbling action of the cleaning solution enhances the cleaning ability of the surfactants, The following examples are presented to illustrate the invention and are not to be considered as self limiting as to the scope of the invention.

EXAMPLE I

An aqueous detergent concentrate was prepared by 20 rnixing the following ingredients:

Component % Weisht Surfactant Al (nonionic) 2. 0 Surfactant B2 (nonionic) 1.0 Fra~trance 0. 1 Optial Brightcner 0.0S
Bleach 05 Soclium Carbonate 0 . 7 5 Sodium Tripolyphosphate 0.1 Socliurn Meta silicatc 0 . I
Dye t race Acid-Base Buffer (pH 11-12) 0.05 Wate r 9 5 . 8 1, Triton N-101 (nonly Phenoxy polyethoxy ethanol containing 9-10 molcs of ethylene oxide)

2. Triton CF-10 (ben~yl ether of Phenol conclensed with ethylene oxicle ) The above concentrate was diluted with four parts of water to one part of concentrate and transferred to a spray can. The can was pressurized to a pressure of about 62 psig and carbon dioxide was injected through a quick-coupler located at the base of the sprayer. The C02 was passed through multiple air jcts below the solution surface and fannecl out for absorption into the cleaning solution. The sprayer was shaken to provide a uniform degree of carbonation and the C02 source was disconnected.
The carbonated aqueous solution was sprayed directly onto a carpet made from a blend of wool and nylon which had been soiled with mud, used motor oil, cocoa and lipstick. The solution emerged from the sprayer as a very active effervescent, white, frothy, foam which rapidly penetrated into the carpet.
The oarpet was brushed with fabric discs and the foam and the rernaining solution was removed by a wet-dry vacuum. I'he carpet dried rapidly and no traces of the soil could be seen. After several months o~ heavy foot traffic no respotting or resoiling could be seen where the original soil had been placed.

EXAMPLE Z

The following concentrate, while very effective, was rather difficult to prepare and had to be formulated using the steps as outlined.
Into a one gallon container was placed 2, 000 mls of water to which wa~ added 100 mls of a nonionic conclensation product of a mixed fatty alcohol having 14-15 carbons with ethylene oxide to produce a polyethoxylated alkanol having an average of 11 ethylene oxide units. (Neodol 45-llJ. The mixture was thoroughly agitated. There was then added 40 mls of a nonionic . . ., ,=. . .

surEactant consisting of a polyoxyalkylene alkanol having 26 to 30 units of propylene oxicle condensed with ethylene oxide such th~Lt the molecule contained 10-20 percent ethylene oxide.
(Pluronic L-61). The mixture was again agitated whereupotl 60 mls of ethylene glycol diethyl ether was added as a wetting agent. After a thorough mi~cing, 150 mls of methylene chloride was added and the solution was agitated until milky in color.
Water was then added to make one gallon of concentrate. One part of concentrate was dilutecl with three parts water and was 10 transferred to a pressure sprayer and carbonated with carbon dioxide under a pressure of about 8~3 psig. Application of this formulation to a soiled carpet in the manner describc d in Example 1 produced the same excellent results. The carpet dried very rapidly due to the presence of methylene chloride in addition to the carbonation and left no noticeable resielue as evidenced by the lack of resoiling over a period of time.

EXAMPI.E 3 -A concentrate was preparecl containing 2 . 5 percent of dodecyl phenol condensed with ten rmoles of ethylene oxide 20 (Sterox DJ) and 2.5 percent of an cthoxylated vegetable oil (Emulphor EL-620) which was clilutcd with watcr at a ratio of one part concentrate to five parts water. Carbonation under a pressure of about 75 psi~ resultecl in a solution that was very efEervescent when applied via a spray no~le to a carpct surfacc:.
The carbon dioxide hclped remove thc aquco~lY solution rom the fibers resulting in rapid clrying oE the clcar- carpet.
Other formulations were prepared using commercial anionic detergents (Tide, Bold, Cheer ctc.) in concentrations of about 1 to 5 percent by weight. Each solution was carbonated as in the above examples. The results obtained in each case were superior to comparable results obtained with the same formulation in an uncarbonated state.
The above examples are illustrative of the claimed invention. However, the scope of the invention is to be limited only by the appended claims.

Claims

1. An aqueous cleaning composition containing from about 0.1 to 5.0 percent by weight of one or more nonionic or anionic surfactants wherein the composition is carbonated and maintained at a pressure of from about 1 to 10 atmospheres.

2. An aqueous cleaning composition according to Claim 1 wherein the composition is carbonated by subjecting the composition to gaseous carbon dioxide under pressure.

3. An aqueous cleaning composition according to Claim 1 wherein the composition is carbonated by subjecting the composition to solid carbon dioxide under pressure.

4. An aqueous cleaning composition according to Claim 1 which additionally contains from about 0.01 to 1.0 percent of an alkaline builder salt.

5. An aqueous cleaning composition according to Claim 4 wherein the alkaline builder salt is selected from the group consisting of alkali metal silicates, phosphates, carbonates and borates.

6. An aqueous cleaning composition according to Claim 1 which additionally contains from about 0.1 to 5.0 percent by weight of a volatile organic solvent having a boiling point below about 100°C.

7. An aqueous cleaning composition according to Claim 6 wherein the volatile organic solvent is a member selected from the group consisting of halogenated hydrocarbons having from one to three carbon atoms, lower alkyl ethers having one ether linkage and unsubstituted hydrocarbons.

8. An aqueous cleaning composition according to Claim 7 wherein the volatile organic solvent is methylene chloride.

9. An aqueous cleaning composition according to Claim 1 wherein the surfactant is nonionic.

10. A method of cleaning textile fibers which comprises contacting the fibers with a carbonated aqueous cleaning solution having a nonionic or anionic surfactant con-centration of between about 0.1 and 5.0 percent by weight.

11. A method of cleaning textile fibers according to Claim 10 which comprises applying the carbonated aqueous cleaning solution to the textile fibers as a pressurized spray.

12. A method of cleaning textile fibers according to Claim 11 which comprises the steps of placing an uncarbonated aqueous cleaning solution into a container capable of being pressurized, introducing carbon dioxide into the container which is maintained at a pressure of between about 1 and 10 atmospheres and applying the pressurized carbonated cleaning solution to the textile fibers.

13. A method of cleaning textile fibers according to Claim 12 wherein the textile fibers are in the form of a carpet.

14. A method of cleaning textile fibers according to Claim 13 wherein the aqueous cleaning solution is carbonated by means of pressurized gaseous carbon dioxide.

15. A method of cleaning textile fibers according to Claim 13 wherein the aqueous cleaning solution is carbonated by means of solid carbon dioxide.

16. A method of cleaning textile fibers according to Claim 14 which comprises mechanically working the carbonated cleaning solution into the fibers and subsequently removing the cleaning solution which is not evaporated from the fibers.

17. A method of cleaning textile fibers according to Claim 15 wherein the carbonated aqueous cleaning solution also contains about 0.01 to 1.0 percent by weight of an alkaline builder salt.

18. A method of cleaning textile fibers according to Claim 15 wherein the carbonated aqueous cleaning solution also contains about 0.1 to 5.0 percent by weight of a volatile organic solvent having a boiling point below about 100°C.