NZ331057A

NZ331057A - Treatment of fabrics with polycarboxylic acid and sulphonic or sulfinic acid

Info

Publication number: NZ331057A
Application number: NZ331057A
Authority: NZ
Original assignee: Ici Plc
Priority date: 1997-07-22
Filing date: 1998-07-21
Publication date: 2000-02-28
Also published as: GB2327432A; CA2243339A1; GB2327431B; GB9815426D0; GB9815428D0; AU7743498A; CA2243350A1; AU7743598A; GB2327432B; GB2327431A

Abstract

The method consists of: applying to the cellulosic textile material an aqueous solution including at least one polycarboxylic acid as a crosslinking agent for the cellulose and at least one sulphonic acid of the formula RSO2OH where R is an alkyl or cycloalkyl group, and unsaturated straight or branched chain hydrocarbyl; and drying the cellulosic textile material and heating it to promote crosslinking esterification of the polycarboxylic acid and the cellulose of the cellulosic textile material. The aqueous treatment solution is also claimed.

Description

New Zealand Paient Spedficaiion for Paient Number 331 057 r •*>j NEW ZEALAND PATENTS ACT, 1953 No Date COMPLETE SPECIFICATION T—.. TREATMENT OF FABRICS JjNTELLtuUAL PROPERTY OFFICE 's m OF NZ j j 2 1 JUL 19S8 I ! received i We, IMPERIAL CHEMICAL INDUSTRIES PLC, a British company, of Imperial Chemical House, Millbank, London SWIP 3JF, United Kingdom, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described m and by the following statement (followed by page - la -) This invention relates to a method of imparting wrinkle and/or crease and/or shrink resistance and/or smooth drying properties to fabrics made from cellulosic fibres or yarns or blends containing 5 cellulosic fibres or yarns More particularly it relates to such a method of treatment which does not involve the use of formaldehyde or formaldehyde derivatives or phosphorus containing compounds Many commercial processes for imparting wrinkle, crease and/or shrink resistance and/or smooth drying properties to cellulooic fabrics, particularly cotton textiles, are known The treated fabrics and 10 garments made from them retain their dimensions and smooth appearance in use and also during machine wash and tumble dry processes Commercially, such properties can be imparted to cellulosic fabrics by a finishing treatment with resinous compositions The most commonly used resins for such finishing are based on 15 formaldehyde derivatives such as formaldehyde-urea or substituted urea addition products such as DMEU and DMDHEU Such resins are believed to function by promoting crosslinking of the cellulose in the fabric thereby imparting the desired properties In recent years, efforts have been made to develop crosslinking agents which do not include formaldehyde or its derivatives to remove the possible evolution of formaldehyde during manufacture, storage and/or use of cellulose, particularly 20 cotton fabrics, treated with formaldehyde addition products Non-formaidehyde crosslinking agents which have been suggested previously include polycarboxylic acids as disclosed by Gaghiardi and Shipee, American Dyestuff Reporter 52, 300 (1963) Rowland et al, Textile Research Journal 37, 393 (1967), disclosed the use of partially neutralized 25 polycarboxylic acids with base prior to the application to the fabric in a pad, dry and heat cure treatment, elaborated US Patent 3526048 Canadian Patent No 2097483 describes rapid esterification and crosslinking of fibrous cellulose in textile form using boric acid or derivatives as crosslinking catalyst Welch et al in US Patents 4975209, 4820307, 4936865 and 5221285 disclose the use of alkali metal salts of phosphorus containing acids, particularly sodium hypophosphite as crosslinking esterification catalysts in the treatment of cellulosic materials The use of sodium hypophosphite has several disadvantages it is expensive, relatively high levels are needed in practice and it tends to cause shade changes in fabrics dyed with sulphur dyes or certain reactive dyes In addition, phosphorus 35 containing effluents can promote algal growth and/or eutrophication or downstream water bodies such as streams and lakes 331057 9 .

The present invention is based on the discovery that certain sulp'iur containing acids, particularly sulphonic and/or sulfinic acids, and their alkali metal salts at lower concentration show accelerating effect on esterification and crosslinking of cellulose by polycarboxylic acids The use of such catalysts can enable the provision of a treatment method that uses neither formaldehyde derivatives or phosphorus compounds, but can give adequately rapid esterification and crosslinking of cellulosic in fibres to provide effective wrinkle, crease or shrink resistance or smooth drying properties to materials made from such cellulosic fibres Thus, in this invention fibrous cellulosic material is treated with a polycarboxylic acid in the presence of a sulphonic and/or sulfinic acid curing catalyst at elevated temperature The process c^n be carried out by impregnating the material with a solution j 0 containing the polycarboxylic acid and the curing catalyst followed by heat treatment to produce esterification and crosslinking of the cellulose with the polycarboxylic acid The present invention accordingly provides, a method of treating fibrous cellulosic textile material which comprises a applying to the cellulosic textile material an aqueous solution includ'ng at least one polycarboxylic acid as a ciosslinking agent for the cellulose and at least one sulphonic acid of the foimula RS020H where R is an alkyl or cycloalkyl group, an unsaturated stiaight or branched chain hydiocarbyl, particularly alkenyl gioup, or an olefinically unsaturated cyclic group or a salt as an esterification catalyst, and 20 b drying the cellulosic textile material and heating it to promote crosslinking esterification of the polycarboxylic acid and the cellulose of the cellulosic textile material In referring to the material as being "cellulosic", we mean that the major part of the fibre forming components of the material is cellulose Thus, the term includes purely cellulosic materials such as cotton and cellulose-rich blends particularly cellulose-rich polyester blends, such as polycotton materials Typically, the material contains from 30 to 100% of cellulosic fibres Typical cellulosic fibre materials which can be included in fabrics treated according to this inventions include cotton, flax, rayon, jute, hemp and ramie It can also be a synthetic cellulosic fibre material such as rayon, particularly viscose rayon or solvent derived rayon commonly called lyocell fibre The cellulosic material can be a blend of fibres of cellulosic materials with non-cellulosic materials and in particular includes blends of cellulosic fibres, particularly cotton, with polyester, particularly polyethylene terephthalate polymer or related copolymers The textile can be a woven (including knitted) or non-woven textile, but as crease resistance is particularly important in clothing, the textile will usually ^ be a clothing textile material The term "formaldehyde free" means that the process does not release formaldehyde during the treatment of the fabric with the resin or during subsequent manufacture of garments or their use including washing and wearing The term "wrinkle or crease resistance" means that a treated fabric is less likely to be wrinkled or creased after being worn or after a laundering operation than it would if it had not been so treated 3 - 1057 The invention uses polycarboxylic acids as cellulose crosslinking agents to improve the wrinkle resistance, shrinkage resistance and smooth drying properties of cellulosic fibre containing textile without the use of formaldehyde or agents that release formaldehyde Some such polycarboxylic acids are known from the literature Suitable polycarboxylic acids for use in the method of this invention include aliphatic, including open chain and alicyclic, polycarboxylic acids, and aromatic polycarboxylic acids Desirably the polycarboxylic acid includes at least 3, particularly at least 4 and often more carboxylic acid groups per molecule Particularly suitable aliphatic polycarboxylic acids include acids in which at least two carboxylic acid groups are separated by 2 or 3, more usually 2, carbon atoms and desirably where the polycarboxylic acid includes a plurality of such arnnged pairs of carboxylic acid groups Where such an aliphatic acid includes an ethylenic double bond, it is very desirable that it is positioned a,p- to a carboxylic acid group, such an aliphatic acid may include a hydroxyl group on a carbon atom also carrying a carboxylic acid group, and further the aliphatic chain or ring may include one or more oxygen and/or sulphur atoms Suitable aromatic acids include those where at least two carboxylic acia groups are attached to adjacent aromatic ring carbon atoms Examples of suitable aliphatic polycarboxylic acids include maleic acid, methylmaleic (citraconic) 2q acid, citric acid, itaconic acid, 1,2,3-propanetricarboxylic acid, 1,2,3,4-butanetetracarboxylic acid (commonly known as BTCA), all c/s-1,2,3,4-cyclopentanetetracarboxylic acid, oxydisuccinic acid, thiodisuccinic acid oligo- and/or poly-maleic acid and/or anhydride (as described in GB 2295404 A and WO 96/26314 A and abbreviated "OMA") and suitable aromatic polycarboxylic acids include benzene hexacarboxylic acid and trimellitic acid The amount of crosslinking agent used will typically be from 1 to 10%, particularly from about 2 to about 7%, by weight based on the dry fabric weight The particular concentration of crosslinKing agent used in the treating solution wi'l depend upon the degree of cross linking desired, the proportion of cellulosic fibres in fabric being treated and the solubility of the crosslinking agent 30 Typically, the concentration is from about 1 to 20%, more usually 2 to 10% particularly from 0 5 to 7 and especially about 5%, by weight of the solution The curing catalysts used in this invention are organic sulphonic acids or their salts Suitable organic sulphonic acid catalysts have the geneial formula RS020H where R is an organic 2 1 33 1 057 group, particularly an alkyl or cycloalkyl group an unsaturated straight or branched chain hydrocarbyl, particularly alkenvl group or an olefinically unsaturated cyclic group Particularly active and effective curing catalysts of this invention include the alkane sulphon'c acids 5 and their alkali metal salts e g methane, ethane, propane, butane, pentane and hexane sulphonic acids, camphor sulphonic acid, isethionic acid (2-hydroxyethane sulphonic acid), methane-di-sulphonic acid and trifiuoromethanesulpnonic acid The sulphonic acid catalyst can be used as the free acid or as a salt, particularly an alkah 10 metal, ammonium or alkaline earth metal salt, or a mixture of the free acid and a salt or salt(s) The salt forming cations are particularly of potassium, sodium, ammonium, magnesium, calcium or a mixture of these cations It is not clear whether the free aud form or the salt form of the curing catalyst is the more active component of the catalyst The form present wll depend on the acidity of the solution used for the treatment of the textile and the effect of the drying and heating &teps We ^ have found that the textile is advantageously treated using a moderately acidic solution, typically having a pH of from 2 to 6, usually not more than 4 5, more usually from 2 5 to 4 and especially about 3 Under such conditions, the curing catalyst may be present as the neutral free acid, as acid anions or a mixture depending on the acidity of the catalyst Generally sulphonic acids are strong enough acids that they will be present as the free acid (often largely dissociatrd) in aqueous solution at pH about 3 The amount of catalyst used will typically be from 10 to 200%, more usually 25 to 150%, desirably 50 to 120%, by weight of the polycarboxylic acid crosslinking agent Expressed as a percentage based 95 on the (dry weight of the) textile being treated, the amount will typically be from 1 to 30%, more usually from 2 to 20%, particularly 2 5 to 10% by weight The concentration used in the treatment solution is typically from 0 1 to 20%, more usually from 0 2 to 10%, particularly from 0 5 to 7%, by weight of the solution The treatment is typically carried out by first impregnating the cellulosic or cellulosic containing textile materials with an aqueous treating solution containing the crosslinking agent and the curing catalyst, and removing excess liquid e g using wringers, with these steps being repeated, if necessary, to obtain the desired liquid pick up The material is then dried to remove the solvent and then cured, eg in an oven, typically at about 150 to 240°C, usually from 160 to 200°C for a time of from 5 35 seconds to 30 minutes, usually 1 to 5 minutes to promote the esterification and crosslinking of the 2 1 hr r; 33 1 0 ^7 cellulose by the polycarboxylic acid Typically the pick up of treatment solution is from 30 to 120%, more usually from 50 to 100%, particularly about 80% of the dry weight of the untreated textile _ We have confirmed the presence of cellulose ester carbonyl groups in material treated according to the invention by FT-IR (Fourier transform infra red) spectroscopy The absorption band of the carbonyls of cellulose esters in infra red spectra has been reported and in the range of 1720 to 1750 cm 1 (Zhbankov, P G , "Infrared spectra of cellulose and its derivatives", Consultant Bureau, New York, 1968, pp 315-316) Our observations show an absorption peak at about 1720 to ^ 1735 cm The treatment solution containing the crosslinking agent and the curing catalyst forms part of the invention which accordingly specifically includes an aqueous solution of at least one polycarboxylic 15 acid cellulose crosslinking agent, particularly at a concentration of from 1 to 20% by weight of the solution, and at least one sulphonic acid of the formula RSCXOH where R is an alkyl or cycloalkyl group an unsaturated straight or branched chain hydrocarbyl, particularly alkenyl group, or an olefinically unsaturated cyclic group or a salt as an esterification catalyst, particularly at a concentration of from 0 2 to 10% by weight of the solution The invention further includes cloth treated by the method of the invention and in particular, a cellulosic textile material, which may be woven (including knitted) or non-woven, which carries residues of at least in one polycarboxvlic acid cellulose crosslinking agent estenfied to hydroxvlic sites in the cellulose and residues of at least one sulphonic acid of the formula 25 RSOiOH where R is an alkyl oi cycloalkyl group an unsaturated straight or branched chain hydrocaibyl, particularly alkenyl group or an olefinically unsaturated cyclic group or a salt esterification catalyst In these aspects of the invention particulaily desirable features aie as described for the method 30 of the invention CPW 50525 The following Examples illustrate the invention All parts and percentage are by weight unless otherwise stated Materials BTCA 1,2,3,4-butanetetracarboxylic acid OMAi oligo-maleic acid made using benzoyl peroxide as the polymerisation initiator OMAii oligo-maleic acid made using hydrogen peroxide/acetic anhydride as the polymerisation initiator MSA methane sulphonic acid 10 Surf Commercial proprietary domestic detergent ex Hindustan lever Test Methods Wrinkle recovery angles (WRA) were determined by ATCC Test Method 66-1990, Wrinkle recovery of fabrics Recovery 15 angle method The wrinkle resistance of woven textiles is lepresented bv the wrinkle recovery angles, the greater the WRA the greater the wrinkle resistance of the fabric Results are reported in degrees Example 1 This Example illustrates the use of MSA (Examples 1a, 1b and 1c) as a curing catalyst for the durable press finishing of cotton fabric using BTCA Cotton cloth test pieces (10 inches square, ca 25x25 cm,) we1 e thoroughly wetted by immersion in a treatment bath containing an aqueous solution (80 ml) of BTCA (5 g, 6 25%w/v) and MSA 25 (concentration given in Table 1) as curing catalyst at a pH adjusted to 3 The wetted cloth was passed between the rolls of a wringer and the process repeated twice to give an overall pick up 80% by weight of the dry cloth The test pieces were stretched on a rack and dried in an air forced draft oven at 85°C for 5 minutes The dried test pieces were then treated in an air draft oven at the temperatures and for the times shown in Table 1 below, in which amounts of BTCA and MSA are 30 expressed as weight % based on dry fabric weight The treated specimens were rinsed for 5 minutes with 1 % Surf solution, rinsed with water and air dried and the WRA's) were measured The WRA results are included in Table 1 below Table 1 Ex No BTCA concn (%) MSA concn (%) Curing Conditions WRA Temp (°C) Time (min) 1a 6 25 6 25 170 2 248 1b 6 25 1 25 180 1 5 268 1c 6 25 1 25 190 1 269

Claims

CPW 50525 - 7 - Example 2 This Example compares MSA ( Example 2) and sodium hypophosphite (comparative Example C2) as curing catalysts for durable press finishing or cotton fabric with BTCA The general procedure of 5 Example 1 was followed using the appropriate catalysts and the results are set out in Table 2 below Table 2 Ex No BTCA concn (%) Catalyst Curing Conditions WRA material concn (%) Temp (°C) Time (min) C2 6 25 NaH2P02 75 180 1 5 271 2 6 25 MSA 1 5 180 2 268-9 Example 3 15 This Example compares MSA (Examples 3a, 3b and 3c) and sodium hypophosphite (comparative Example C3) as curing catalysts for durable press finishing of cotton fabric with OMA as the crosslinking agent, Examples 3a and 3b used OMAi and Examples 3c and 3C OMAn The general procedure of Example 1 was followed using the appropriate catalysts in the treatment bath in the concentrations stated in Table 3 below and the results including WRA data are set out in Table 3 20 below Table 3 Ex No Resin Catalyst Curing Conditions WRA material concn (%) material concn (%) Temp (°C) Time (min) 3a OMAi 5 MSA 5 180 2 250 3b OMAi 5 MSA 1 180 2 252 3c OMAn 5 MSA 5 180 2 244 C3 OMAii 5 NaH2P02 6 180 1 5 246 30 Example 3 Cotton cloth specimens were prepared by the general procedure of Example 1 using 5% BTCA as the treatment resin and MSA as the curing catalyst at levels of 5% and 1 % by weight on the dcy fabric The specimens were heat treated at 180°C for 90 seconds FT-IR spectroscopic examination 35 of both specimens, with particular attention to the frequency range 1750 to 1720 cm"1, showed absorptions at 1728 cm"1 attributed to the presence of crosslinked ester groups - 8 - WIIAT wr CLAIM IS 10 -) 15 J 4 20 5 6 30 7 35 8 A method of treating fibious cellulosic textile material which comprises a applying to the cellulosic textile matei lal an aqueous solution including at least one polycarboxylic acid as a crosslinking agent lor the cellulose and at least one sulphonic acid ol the loimula RSO:OH where R is an alkyl or cycloalkyl gioup an unsaturated stiaight or blanched chain hvdrocarbyl, particularly alkenyl group oi an olefinically unsatuiated cyclic group or a salt as an estei lfication catalyst and b drying the cellulosic textile mateual and heating it to piomote crosslinking estei lfication of the polscaiboxylic acid and the cellulose of the cellulosic textile material A method as claimed in claim 1 whuein the catalyst is an alkane sulphonic acid '\ method as claimed in claim 2 whetein the catalvst is methane sulphonic acid A method as claimed in any one ol claims 1 to 3 wherein the polycarboxylic acid includes at least two carboxylic acid gioups sepaiated by 2 oi 3 carbon atoms A method as claimed in any one ol Uanns I to 4 wheiein the polycarboxylic acid ciosslinking agent is one oi more ol maleic acid methylmaleic acid, citnc acid itaconic acid I 2 3-piopanetricaiboxylic acid 1 2 3 4-butanetetracai boxy lie acid all c/s-1 2 3 4-cyclopentanetetiacarbox) lie acid, oxvdisuccinic acid thiodisuccinic acid, oligo- and/ot polv-maleic acid and/oi anhydnde benzene hexacarboxy lie acid and trimelhtic acid A method as claimed in claim 1 whuein the polycaiboxylic acid is I 2 3 4-butane tetra catbowltc acid and/oi oligo- and/oi polv-maleic acid and the catahst is methane sulphonic acid A method as claimed in any one of claims 1 to 6 whuein the amount of polycarboxylic acid ciosslinking agent used is Itom I to 10% by weight based on the dry fabric weight A method as claimed in claim 7 whuein the amount of polycaiboxylic acid used is from 2 to 7% by weight based on the dry weight INTELLECTUAL PROPERTY OFFICE S OF NZ I 13 jan 2000 received 10 15 -9- 3310- F A method as claimed in any one of claims 1 to 8 wherein the amount of sulphonic acid catalyst used is from 10 to 200% by weight of the polycarboxylic acid crosslinking agent 5 10 A method as claimed in claim 9 wherein the amount of sulphonic acid used is from 50 to 120% by weight of the polycarboxylic acid crosslinking agtnt 11 A method as claimed in any one of claims 1 to 10 wherein the heating step is carried out at a temperature of from 150 to 240°C 12 A method as claimed in claim 1 1 wherein the temperature is from 160 to 200°C 13 A method as claimed in any one of claims 1 to 12 wheiein the heating step is carried out for a time of from 5 seconds to 30 minutes 14 A method as claimed in claim 13 wherein the tune is from 1 to 5 minutes 15 An aqueous treatment solution of at least one polycarboxylic acid cellulose crosslinking agent, at a concentration of from 1 to 20% by weight of the solution and at least one 20 sulphonic acid of the formula RSOiOH where R is an alkyl or cycloalkyl gr d, an unsatuiated straight or branched chain hydiocarbyl, particularly alkenyl group, or an olefinically unsatuiated cyclic gioup oi a salt as an esterification catalyst, at a concentration of from 0 2 to 10% by weight of the solution 25 16 A cellulosic textile material which carries residues of at least one polycarboxylic acid cellulose crosslinking agent esterified to hydroxylic sites in the cellulose and residues of at least one sulphonic acid of the formula RSO^OH where R is an alkyl or cycloalkyl group, an unsaturated straight or branched chain hydrocarbyl particularly alkenyl group, or an olefinically unsaturated cyclic group or a salt 30 17 A method as claimed in claim 1, substantially as hereinbefore described with reference to any one of Examples 1 to 3 18 A cellulosic textile material whenevei tieated by a method as claimed in any one of 35 claims 1 to 14 INTELLECTUAL PROPERTY OFFICE i OF NZ 1 3 JAN 2000 RECEIVFn |