IE43111B1 - Polyglycol ether derivatives and wetting, washing and compositions containing them - Google Patents

Abstract

1488108 Polyglycol ether formals HOECHST AG 27 May 1976 [28 May 1975] 22081/76 Heading C3R [Also in Divisions C2 and C5] Compounds have the general formula in which R1 is a C 8-22 alkyl or alkenyl radical or a C 14-26 mono-, di- or tri-alkylphenyl radical; R2 is a C 1-5 alkyl radical; n=5-50 and X is ethylene or propylene; the ether chain (XO) n either consists entirely of ethoxy units or contains at most n/5 isopropoxy units. I may be prepared by reacting 1 mole of R1O(XO) n H with 3-8 moles of an alcohol R2OH and 0À5-1À0 moles of formaldehyde. Reaction takes place at elevated temperature, e.g. 120-190‹ C., and the by-product formal R2OCH 2 OR2 and water are removed by azeotropic distillation. In examples adducts of C 10-12 or C 12-18 fat alcohols with 9 or 13À5 moles of ethylene oxide are reacted with either n- or iso-butanol and paraformaldehyde using as catalyst cone. H 2 SO 4 or p-toluenesulphonic acid.

Description

The present invention relates to non-ionic polyglycol ether jrivatives and to the use of these derivatives in low foaming siting, washing and cleansing agents which are resistant to Lkali.

It is known tnat polyoxethylated alkyl-phenols and polyoxfchylftted fat alcohols have surface-active properties which ike them very suitable'for use in wetting, washing and Leansing agents or as emulsifiers. In many fields of appliition, however, for example when used in cleansing: and washing *ents for dishwashers and washing machines as well in the Leansing of metal surfaces according to the spray process, le strong foaming power of these compounds is disadvantageous.

Attempts have already been made to reduce the strong tenancy to foaming of such washing and cleansing agents by simulineously using suitable components, for example block polymers E polypropylene- glycol and ethylene oxide or other foaming aducing systems. However, satisfactory results have not always sen obtained. Moreover, a disadvantage of the use of the known ah-ionic surface-active compounds is that these compounds are at sufficiently stable in the presence of strongly alkaline abstances, for example alkali metal hydroxides, alkali metal ilicates or alkali metal phosphates. By the action of the Ikalis, the non-ionic products undergo decompositions or dis□lorations.

Now, we have found that surface-active compounds which can e used with special advantage as tensides in wetting, washing nd cleansing agents, are obtained by preparing from the addiion products of alkylene oxides and long chain aliphatic alohols or mono-, di- or tri-alkyl-phenols, hereinafter re- 2 43111 ferred to as polyglycol ethers, the mixed formals which are closed in the terminal position.

Thus, the present invention provides nonionic polyglycol ether derivatives of the general formula I Rj.-O-CX-O^CHj-O-R (X) in which R-|_ represents a straight chain or branched alkyl or alkenyl group having from 8 to 22, preferably 8 to 18, carbon atoms or a mono-, di- or trialkyl-phenyl radical having from 14 to 26, preferably 16 to 24, carbon atoms, R2 represents a straight chain or branched alkyl radical having from 1 to 5, preferably 4, carbon atoms, n represents a number from 5 to 50, preferably 5 to 30, and X represents an alkylene radical having 2 or 3 carbon atoms, the ether chain (X-0)n consisting completely of ethoxy units or containing at most n/5 isopropoxy units.

The polyglycol ether derivatives of the invention of the formula I may be prepared by reacting 1 mole of an alkyl-, alkenyl- or alkylphenyl-polyglycol ether of the formula Rl-O-(X-O)n-H, in which R-^,Χ and n have the meanings given above, with from 3 to 8 moles, preferably, 4 to 6 moles, of an alcohol of the formula R2OH, in which R2 has the meaning given above, and from 0.5 to 1.0, preferably 0.52 to 0.58, moles of formaldehyde per OH-equivalent, in the presence of a strong acid, for example sulfuric acid or p-toluene-sulfonic acid as catalyst, at an elevated temperature.

For the reaction, formaldehyde in the form of a concentrated aqueous solution or, preferably in the form of para-formaldehyde may be used; however, it is also possible to use the equivalent amount of trioxane. i 'lie strong acid used as the catalyst is suitably added in ich an amount that an acid number of about 2 to 8, preferably to 5, (mg of KOH consumption per g of reaction mixture) is .intained in the reaction mixture. The reaction is suitably ifected under stirring and simultaneous removal of the dialkyl>rmal and of the reaction water by azeotropic distillation, l general, the reaction is carried out at temperatures in the mge of from about 120° to 190° C, preferably 160° to 170° C, itil water is no longer separated; in general, this is the ise after a reaction period of 3 to 7 hours. The reaction ixture is then cooled and neutralized. It is suitable to add i appropriate filtration auxiliary agoht, for example silica 3l, in quantities of from about 0.5 to 3 % by weight. The ialkyl formal still present in the reaction mixture is then sparated by distillation, suitably under reduced pressure, rom the mixed formal formed. The mixed formal so obtained can ibsequently be freed by filtration from any salts present, iie dialkyl formal of the formula RgOCHgORg separated by distilation may then be used for further reactions under considerat)n of the proportion of the alcohol RgOH which it contains and tiich can be determined from the hydroxyl number of the dilkyl-formal.

A characteristic feature of the process for preparing the olyglycol ether mixed foraals of the invention is the formation nd use of a dialkylformal Rg-OCHg-ORg which fulfils the function f a dragging agent for the azeotropic removal of the water nd simultaneously enters, as reective component, into the quilibrium reaction for the formation of the polyglycol ether ixed formal. - 4 43111 In an aqueous solution, the compounds of the invention have a very weak tendency to foaming. Therefore, they may be used with particular advantage as antifoaming additives for non-ionic and cationic compounds in wetting, washing and cleansing agents. The products of the invention are stable also in alkaline solution and in the presence of caustic alkali.

They have excellent surface-active properties and may, therefore be used with particular advantage for such purposes where good cleansing and wetting properties without or with only slight foam formation are required.

Owing to their good stability to alkalis and their antifoaming properties, the compounds of the invention may be used advantageously for the preparation of rinsing and cleansing agents, in particular of industrial cleansing agents, for example those used for the cleansing of metal, glass, dishes, bottles and the like. The compounds of the formula I or even mixtures of the compounds of the invention are suitable for the preparation of liquid or solid- washing or cleansing agents.

The may be used either alone or in combination with other known non-ionic, cationic or anionic substances, builders or other additives or auxiliary substances in the washing ana cleansing agent formulations.

Suitable anionic washing raw materials which may be used as constituents of the washing and cleansing agents of the invention containing the polyglycol ether mixed formats are, for example, those of the sulfonate or sulfate type, for example alkyl-benzene-sulfonates, in particular the n-dodecylbenzene- 5 Lil iulfonate, the olefin-sulfonates as those obtained, for example ly the sulfonation of primary or secondary aliphatic monoilefins with sulfur trioxide and following alkaline or acidic Lydrolysis, as well as alkane-sulfonates as those obtained by :ulfochlorination or sulfoxidation and subsequent hydrolysis or eutralization from n-alkanes or by bisulfite-addition to lefins. Suitable anionic washing raw materials are further4 ore (χ-sulfσ-fatty acid esters, primary and secondary alkylulfates and the sulfates of oxalkylated higher molecular weight Icohols. Other anionic compounds which may he used in the ashing and cleansing agents are the higher molecular sulfated artial ethers and partial esters of polyhydric alcohols, such s the alkali metal salts of the mono-alkyl ethers or monoatty acid esters of the glycerin-mono-sulfuric acid ester r of the 1,2-dioxypropane-sulfonic acid. Furthermore, there ay be used the sulfates of oxalkylated fatty acid amides or lkyl-phenols, as well as fatty acid taurides and fatty acid sethionates. Suitable anionic washing raw materials that may e used are furthermore the alkali soaps of fatty acids of atural or synthetic origin, for example the Sodium soaps f coconut oil, coprah oil or taSow fatty acids.

The anionic washing raw materials are used preponderantly n the form of the sodium, potassium or ammonium salts; however, hey may also be used in the form of their salts with organic ases, for example with mono-, di- or tri-ethanolamine. If the entioned surface-active compounds have an aliphatic hydroarbon radical, this radical should have from about 8 to 24 arbon atoms and be, preferably, a straight chain radical. - 6 43111 In the compounds which contain an araliphatic hydrocarbon radical, the alkyl radicals should have 6 to 18 carbon atoms.

As non-ionic washing raw materials which may be contained 5 in the washing and cleansing agents of the invention, there may be used above-all polyglycol ether derivatives of long chain alcohols, carboxylic acids or alkyl-phenols which contain 3 to 30 glycol ether groups and 8 to 22 carbon atoms in the hydrocarbon radical. It is preferred to use such polyglycol ether derivatives whose number of ethylene-glycol ether groups is 5 to 15 and whose hydrocarbon radicals are derived from primary, straight chain alcohols of 8 to IS carbon atoms or of alkyl-phenols having alkyl radicals of 6 to 14 carbon atoms. The addition of 3 to 15 moles of propylene oxide to the mentioned polyethylene-glycol ethers yields washing raw materials which are distinguished by a low foaming power and which may likewise be contained in the washing agents of the invention.

Other suitable non-ionic washing raw substances are the 2Ω water-soluble polyethylene-oxide addition products which contain about 10 to 100 propylcne-glycol ether groups and 20 to 250 ethylene-glycol ether groups, with prOpyleneglycols and alkyl-propylene glycols having 1 to 10 carbon atoms in the alkyl radical. The last-mentioned compounds normally contain 1 to 5 ethylene-glycol units per unit of propylene-glycol. As jtion-ionic washing raw materials, there may furthermore also be used those of the type of aminoxides and sulfoxides, which may optionally also be oxallcylated. - 7 As builders which may also be added to the washing and leansing agents of the invention, especially the condensed ihosphates such as tripolyphosphates and, in particular, the ienta-sodium di-polyphosphate, may be used. The tri-polyphosihatos may also be used in admixture with phosphates of a igher condensation degree, such as acid or neutral pyrOhosphates.

The condensed phosphates may also be replaced totally or artially by organic, complex-forming amino-polycarboxylic cids, Among these, there may be mentioned especially the Ikali metal salts of nitrilo-triacetic acid and of ethyleneiamino-tetracetic acid. Suitable salts are furthermore the alts of diethylene-triamino-pentaacetic acid, and the higher omologues of the mentioned amino-polycarboxylic acids, such as oly-(N-succinic acid)-ethylene-amines and poly-(N-tricarbllylic acid)-ethylene-imines having average molecular weights f from 500 to 500 000.

Other suitable builders are the Complex-forming wateroluble potassium and sodium salts of higher molecular weight oly-carboxylic acids, for example of polymers of ethylenically nsaturated mono-, di- and tri-carboxylic acids, such as acrylic cid, maleic acid, fumaric acid, itaconic acid, citric acid, conitic acid, mesaconic acid and methylene-malonic acid. Even opolymers of these carboxylic acids one with the other or with ther copolymerizable substance, such as ethylenically unaturated hydrocarbons, for example ethylene, propylene, isoutylene and styrene, or with ethylenically unsaturated monoarboxylic acids such as acrylic acid, methacrylic acid and - 8 4311 crotonic acid or other ethylenically unsaturated alcohols, ethers, esters, amides and nitriles, may be used.

As builders, there may furthermore be used the complex forming polyphosphonic acid salts, for example the alkali metal salts of polyphosphonic acids, in particular amino-tri-(methylene-phosphonic acid), ethylene-aiphospnonic acid, meLhylenephosphonic acid and l-hydroxyethane-l,l-diphosphonic acid in the washing and rinsing agents. Finally, there may also be used mixtures of the mentioned complex-forming substance one with another or with other additives, for example alkali metal salts, in particular sodium silicates, furthermore carbonates, bicarbonates, borates and citrates.

Among the other additives and auxiliary agents of the washing and cleansing agents are mineral per-compounds, as well as activating agents and stabilizers for these per-compounds, optical brighteners, furthermore enzymes of the classes of proteases, lipases and amylases, and the neutral salts, in particular sodium sulfate, and substances that have a bacteriostatic action. There may al20 . so be added the khown greying inhibitors, in particular carboxymethyl-cellulose. If necessary, the washing and cleansing agents may furthermore contain known anti-foming additives, for example fatty acids or their alkali metal salts containing 20 to 24 carbon atoms, as well as higher molecular fatty acid ester.

The content of compounds of the invention in the washing and cleansing agents^formulations may vary within wide limits. Depending on the purpose and condition of the application of the washing and cleansing agents, it is in general about 1 to - 9 a reaction product of 1 mole of a alcohols and 13.5 moles of ethylene oxide, n-butanol, 0% by weight, preferably 2 to 10% by weight. However, it Is Iso possible to use quantities' exceeding this ange. Moreover, the novel compounds of the formula X are ecomposable biologically and satisfy therewith the legal reuirements existing in many countries.

The washing and cleansing agents may be used in solid, in articular in powdery form or they may have, preferably, a ater-containing liquid consistency.

The following Examples illustrate the invention, EXAMPLE 1: 784 g (1 mole) of C10/12 fat 370 g (5 mole) of 04.5 g (3,15 mole) of paraformaldehyde and 2.5 ml of H2S04 ere introduced into a flask having a capacity of 2 liters and rovided with stirrer, thermometer and a device for removing he reaction water by azeotropic distillation, and, while tirring, at a reaction temperature of 160° C, the reaction ater was eliminated.

The amount of para-formaldehyde corresponded to the theoetical amount + 5% excess.

After the elimination of water ceased, the whole was cooled o 100° C, the catalyzing acid contained in the reaction mixure Was neutralized with a solution of sodium methylate, while dding simultaneously silica gel as filtration auxiliary agent.

Thereafter, the excess dibutylfortnal was distilled off fron he mixed formal formed. This was effected at a temperature of about 140° C at maximum and at about 20 mBar.

The mixed formal so obtained was freed from the salts it still contained by filtration.

Weight of the quantity obtained: S2C g = 95% of the theory. The turbidity value oi this product in a 1% aqueous solution was found to be at 41.8°; the residual OH-number was 12.5.

At 30° C, formal constituted a brownish clear liqxiid.

The dibutylformal recovered was again used in further reactions, under consideration of the proportion of butanol, which could be determined from the hydroxyl-number of the dibutylf ormal.

EXAMPLE 2: 622 g (1 mole) of a reaction product of 1 mole of fat alcohol and 9 moles of ethylene oxide, 320 g of dibutylformal (recovered, hydroxyl-number 45 (= 0.26 OH equivalents)), g (1 mole) of n-butanol, .6 g (1.185 mole) of paraformaldehyde, and 2,5 ml of concentrated HgSO^ were reacted in the same manner as described in Example 1 in an apparatus analogous to that described in said Example. To obtain the required dibutylformal quantity, only 1 mole of fresh butanol per one mole of fat alcohol oxethylate were needed.

Yield: 655 g = 96% of the theory, Residual Oil number: 12.3, Turbidity value' (in 1% aqueous solution): 31,5° C.

EXAMPLE 3: In the same manner as described above, there v/ere reacted: 549 g (1 mole) of a reaction product of 1 mole of Cq2/lS” fat alcohol and 8 moles of ethylene oxide, 370 g (5 moles) of n-butanol, 94.5 g (3.15 mole) of paraformaldehyde, and 2.5 ml of concentrated IioS0 . 4 Yield: 613 g = 96.5 % of the theory.

Residual OH number: 17 Turbidity value (in an 1% aqueous solution): 24° C. EXAMPLE 4: In the same manner as described above, there were reacted: 622 g (1 mole) of a reaction product of 1 mole of fat alcohol and 9 moles of ethylene oxide, 370 g (5 moles) of isobutanol), 94.5 g (3.15 moles) of paraformaldehyde, and 2.5 ml of concentrated HgSO^.

Yield: 650 g - 95% of the theory.

Residual OH-number: 11.5.

Turbidity value (in an 1% aqueous solution): 32° C.

EXAMPLE 5: In the same manner as described above, there were reacted: 780 g (1 mole) of an addition compound of 13.5 moles of ethylene oxide and 1 mole of a alc°l10-1·» 320 g of dibutylformal, recovered, (0H-number 90), g (1 mole) of n-butanol, 39,7 g (1,32 mole) of paraformaldehyde, and 2.5 ml of concentrated II^SO^. -12 43111 Yield: P-30 g = 96'% of the theory.

Residual OH-number: 12.

Turbidity value: (in a 1% aqueous solution): 41° C.

EXAMPLE 6: In the apparatus described in Example i, there were reacred: 622 g (I mole) of an addition compound of 9 moles of ethylene oxide and 1 mole of a c^Q/q2“iat alc°bol! 430 g (25 moles) of dibutylformal, highest purity (OH-number 2), and g of p-toluene-sulfonic acid.

The reaction components were introduced jointly and boiled for 2 hours under reflux at a sump temperature of about 160° C. After cooling to 100° C, the mixture was neutralized with a solution of Na-methylate and the excess dibutylformal was re15 moved as described in Example 1.

In the dibutylformal removed by distillation, the butanol set free by the trans-formalization was determined with an OH-numbei’ of 34.

Yield of mixed formal: 650 g = 95 % of the theory.

Residual Oil-number: 18.

Turbidity value (in an 1% aqueous solution): 34.7° C.

In the following Examples of technical applications, the following compounds of the formula I have been used (EO standing for ethylene oxide). The compounds were prepared according to 2 ζ the method described in Example 1, Product A Cio/Ci^-alcohQi-SEO-butyl-mixed formal.

Product Β Cg/C-^-alcohol-SEO-butyl mixed, formal.

Product C C-^g/C^-alcohol-lOEQ-butyl mixed formal.

EXAMPLE 7: An alkaline composition for cold cleansing was prepared by :irring the following components: parts by weight of a dodecyi-benzenesulfone sodium salt 7 parts by weight of product A, parts by weight of petroleum having a boiling range of from 190° to 240° C, parts by weight of n-butanol, parts by weight of oleic acid, part by weight of an aqueous sodium hydroxide solution (38° Bfe), part by weight of sodium tripolyphosphate, parts by weight of trisodium phosphate, and 29 parts by weight of water.

EXAMPLE 8: An alkaline cleansing agent for dishwashing compositions insisted of the following constituents: 2,0 parts by weight of product A, 41.5 parts by weight of anhydrous sodium meta-silicate, 35.0 parts by weight of sodium tripolyphosphate, 1.5 parts by weight of the sodium salt of dichloro-isocyanuric acid/ .0 parts by weight of sodium carbonate.

During mixing, the liquid product was sprayed on the other powdery substances.

EXAMPLE 9: A powdery scouring agent consisted of the following components: parts by weight of a secondary sodium-alcane-sulfonate, having 13 to 18 carbon atoms in the alkyl radical, part by weight of product B, parts by weight of tri-sodium phosphate, parts by weight of sodium pyrophosphate, parts by weight of sodium carbonate, and parts by weight of sodium sulfate.

The scouring agent was prepared by simple mixing of the components.

EXAMPLE 10: A liquid disinfecting cleansing agent was prepared by mixing the following components: parts by weight of coco-nut fat alkvl-dimethyl-benzylammonium chloride, parts by weight of product C, parts by weight of water, EXAMPLE 11: For preparing a powdery disinfecting cleansing agent 20 parts by weight of coco-nut-alky i-dimethyl-benzyl-animonium chloride, parts by weight of sodium carbonate, parts by weight of sodium tri-polyphosphate, and parts by weight of product C were mixed intensively. - 15 3.1 EXAMPLE 12: For preparing an alkaline spray cleansing agent for metal orfaces, there were well mixed in a mixing drum parts by weight of sodium hydroxide (pulverized), part g fcy v/siglit oi sodium silicnio, parts by weight of tri-sodium orthophosphate, and parts by weight of sodium carbonate Bd, with running drum, 5 parts by weight of product A were prayed onto the mixture and the whole was further mixed for 3iae time.

This spray cleansing agent showed good cleansing effects pon spraying and cleansing of metal surfaces in aqueous soltion and no disturbing formation of foam. The product was also Kind to be stable during storage.

EXAMPLE 13: A liquid, neutral spray cleansing agent for metal surfaces id the following composition: parts by weight of the triethanol-amine salt of coconutfatty acid, 1.5 parts by weight of an addition production of 8 moles of ethylene oxide and 1 mole of nonyl-phenol, 2,5 parts by weight of product A, and parts by weight of water.

When cleansing metal surfaces with a 3% solution of this oduct, a good degreasing oi the surface was obtained without am formation.

EXAMPLE 14: The liquid formulation of a clear rinser had the following imposition: parts by weight of product C, parts by weight of a reaction pi-oduct of 1 mole of iso-tridccyl-alcohol and 5 moles of ethylene oxide, parts by weight of citric acid, and GO parts by weight of water· This clear rinsing agent was tested in a commercial dishat washing automate at 80° C and a quantity of 0.5 g per liter. Even if hard water was used, no deposits or veils were observed on the goods rinsed. Foam formation was very low.

EXAMPLE 15: An alkaline bottle cleansing agent was prepared by mixing the following components: parts by weight of penta-sodium tri-polyphosphate, parts by weight of sodium meta-silicate, 32 parts by weight of sodium carbonate, parts by weight of sodium hydroxide (pulverized), and parts by weight of product A.

When used in a bottle cleaning machine, the product showed no foam formation.

With an application concentration of 1.5 percent by weight, beer and milk bottles, which were partially still provided with labels, were cleansed perfectly. The labels were well separated.

The disinfecting cleansing agent described in Example 10 n c was tested for comparison purposes according to DIN 53902 (number of beats producing foam) and compared with disinfecting cleansing agents df analogous structure, but which contained instead of product C of the invention the same amount of the following nroducts: .1 . Reactiuii product’οί 1 «ole oi oleyl alcohol and 12 moles of ethylene oxide (product U) . Reaction product of 1 mole of C^2 ~ C^-oxo- alcohol and 9 moles of ethylene oxide (product V) . Reaction product of 1 mole of Ο^θ - C^g-alcohols. and 5 .moles of ethylene oxide (product W).

For the tests, the foam cleansing agents were used in a oncentration of 5 g per liter. The foaming behaviour was desrmined at 40° C and 60° C. The results are contained in the allowing Table 1: Table 1 naming behaviour of disinfecting cleansing agents according to Example 10 Height of foam in cm (DIN 53902) Product 40° C 60° C c. 120 170 V 320 350 V 260 250 w: 190 190 In the same manner, there was tested the foaming behaviour f a dishwashing rinsing agent according to Example 8 in comirison with dishwashing agent of analogous structure which conlined instead of the product C of the invention the same amount E a reaction product of 1 mole of isotridecyl alcohol and 10 >les of ethylene oxide (product J). The tests were carried out ι water having- a German hardness of 0° and 15° .at 40 C with concentration of the rinsing agent of 5 g per liter. The reilts are shown in the following Table 2, Table_2 Foaming behaviour of machine dishwashing rinsing agents according to Example 8 Height of foam in cm at 40° C (Dll. 53902) 5 Product___Water 0° Gh__Water 15° Gh_ without load with load without load with load immedia- afteriamedia-after immedia-after immedia- after tely 5' tely 5' tely 5' tely 5' C - ---10 J DO 70 100 60 90 60 80 60 The foaming behaviour of the bottle cleansing agent described in Example 15 was tested in comparison with a bottle cleansing agente of analogous structure which contained instead of product A the same amount of a. a reaction product of 1 mole of isotridecyl alcohol and moles of ethylene oxide (product X) and b. a reaction product of 12 mole's of ethylene oxide and 1 mole of hexadecyl alcohol, which had been further reacted with mole of benzyl chloride (product Y).

The foaming tests were carried out according to DIN 53902 20 at 20®, 50° and 70° C with solutions which contained 5 g per liter of the respective bottle cleansing agent. The results of the tests compiled in Table 3 show distinctly the superiority of the bottle cleansing agent of the invention over the products used for the comparison.

Claims (3)

1. A polyglycol ether derivative of the formula Rj-O-(X-0) n -CH 2 -O-R 2 in which is an alkyl or alkenyl radical having from 8 to 22 carbon atoms, or a mono-, di- or trialkyl-phenyl radical 5 having from 14 to 26 carbon atoms, R 2 is an alkyl radical having from 1 to 5 carbon atoms, n is a number from 5 to 50, and X is an alkylene radical having 2 or 3 carbon atoms, the ether chain (X-0) n consisting completely of ethoxy units or containing at most , „ n 10 _ isopropoxy units.

2. A polyglycol ether derivative as claimed in claim 1, in which R 2 is a butyl radical.

3. A process for preparing a polyglycol ether derivative 15 as claimed in claim 1, which comprises reacting 1 mole of an alkyl-, alkenyl- or alkyl- phenyl-poly-glycol ether of the formula R 1 -O-(X-O) n -H with from 3 to 8 moles of an alcohol of the formula R 2 0H, 20 in which R^, X, n and R 2 have the meanings specified in claim 1, and from 0.5 to 1.0 moles of formaldehyde in the presence of a strong acid at an elevated temperature and removing the resulting dialkylformal of the formula R 2 OCH 2 OR 2 and water by azeotropic distillation. 21 A process as claimed in claim 3, wherein the reaction carried out at a temperature of from 120° to 190°C. A process as claimed in claim 3 carried out substantially described in any one of Examples 1 to 6 herein. A polyglycol ether derivative as claimed in claim 1 whenever epared by a process as claimed in any one of claims 3 to 5. A wetting,washing or cleansing composition which contains polyglycol ether derivative as claimed in claim 1 together th a carrier or diluent. A composition as claimed in claim 7 which contains e polyglycol ether derivative in an amount of from 10 to 20% weight. A composition as claimed in claim 7 substantially as scribed in any one of Examples 7 to 15 herein.