DK171776B1 - Process for Two-Step Treatment of Cellulose Material to Make it Flame Retardant and Curl Resistant - Google Patents

Abstract

Flame retardant cellulosic fabrics having reduced shrinkage are obtained by treatment of fabric with a tetrakis hydroxymethyl phosphonium compound or condensate and then curing with ammonia, followed by treatment involving reaction of the fabric with a non self-condensing methylolamide under aqueous acid conditions. The order of treatment can also be reversed.

Description

DK 171776 B1

The present invention relates to a method of treating a cellulose textile material to render it both flame retardant and crease resistant by treating the material in two stages, one of which is an impregnation with a tetrakis phosphonium compound with subsequent curing with gaseous ammonia, and the second is an impregnation with a non-self-condensing methylolamide having at least two methylol groups with subsequent curing.

Cotton fabrics have been made flame retardant by impregnating with tetrakis (hydroxymethyl) phosphonium (THP) compounds or precondensates thereof, followed by curing with heat or ammonia. The fabrics have flame retardant properties which are resistant to washing. However, their other physical properties, especially curl resistance and shrinkage, are often poorer, limiting their use as iron-light fabrics for use, for example, for clothing.

In an attempt to overcome these limitations, THP-cured fabric has been treated with a resin, followed by heat-curing (Rowland and Mason, Textile Research Journal 1977 20 pp. 365-71 and 721-8).

A method of the above-mentioned kind has now been provided in which a cellulose textile material is obtained which is flame retardant and also curl resistant, i.e. has an improved combination of strength and light-weight properties.

The method according to the invention, which is of the kind set forth above, is peculiar to the object by carrying out the following two steps in random order: (i) treating a substance of cellulose fibers, such as cotton, or a mixture of cellulose fibers with polyester fibers, with an aqueous solution of a tetrakis (hydroxymethyl) phosphonium compound or a condensate thereof with urea, followed by curing with gaseous ammonia, and (ii) impregnating the substance with an aqueous solution of a pH value less than 3 of the non-self-condensing methylolamide, preferably a methylolated cyclic urea, e.g. dimethylol-ethylene urea, 1,3-N, N-dimethylol-4,5-dihydroxyethylene urea, dimethylol-propylene urea, its 5-methoxy-5,5-dimethyl and 5-hydroxy analogs and the 5-alkyl-imino analogs of dimethylopropylene urea and tetramethylol - acetylene urea, and subsequent wet curing of the substance while having a moisture content of 6% to 90%.

Preferably, the method of treating the substance is a process wherein the substance containing a cured polymer, derived from a tetrakis (hydroxymethyl) phosphonium compound or condensate thereof with urea, is impregnated with a non-self-condensing methylolamide having at least 2 methylol groups (which may optionally be have been alkylated) and the methylolamide reacts with the substance under aqueous acidic conditions at a pH less than 3. In this preferred process, the substance initially has a cured THP polymer. The substance may have been impregnated with an aqueous solution of a THP salt, mixed with a nitrogen compound which can be condensed therewith, such as melamine or methylated melamine or urea, or with a solution of a precondensate of this salt and nitrogen compound, or with a solution of THP salt or at least partially neutralized THP salt, for example 25 THP hydroxide, with or without nitrogen compound, and then the impregnated substance is dried and cured by heat and / or ammonia. Preferably, the substance is impregnated with a solution of a precondensate of THP salt, for example chloride or sulfate, and urea in a molar ratio of urea 30 to THP of 0.05-0.8: 1, e.g. 0.05-0.6: 1 , example as described in U.S. Patent No. 2,983,623 or 4,078,101, and cured with ammonia, for example, as described in U.S. Patent No. 4,145,463, 4,068,026 or 4,494,951. After curing, the substance is usually post-treated by hydrogen peroxide oxidation, rinsing and neutralization and further rinsing. The substance is then dried. The cured substance usually carries 8-25%, for example 8-20% or 14-20% cured THP polymer, based on the weight of the untreated substance), with lighter substances carrying more than heavier.

The ΊΉΡ-cured substance is impregnated with an aqueous solution of a non-self-condensing methylolamide having at least two methylol groups or optionally an alkyl ether thereof. These methylolamides, also known as "reactant resins", do not substantially condense even under their reaction or cure conditions with the cellulose on the substance. The compounds are usually free of N-H groups, except to the small extent to which such groups may be present in dissociation products in equilibrium with these compounds. These methylolamides are preferably methylated cyclic ureas or O-alkylated derivatives thereof. Such compounds may have the formula

Z - N (R ') - CO - N (R2) - Z

wherein each Z group is a CH 2 OH or Cl 2 OR group wherein 20 R is alkyl, for example with 1-6 C atoms such as methyl, and R 1 and R 2 together form a divalent aliphatic group, as with the two nitrogen atoms and the carbonyl group forms a 5-, 6- or 7-membered ring. The divalent aliphatic group may have the formula -CR3R4- (Y) n-CR5R6- wherein R3, R4, R5 and R8, which may be the same or different, are each a hydrogen atom or a hydroxyl group or alkoxy group, for example with 1 -6 C atoms such as methoxy, n is 0, 1 or 2, preferably 0 or 1, and Y is an oxygen atom, or the NR7 group wherein R7 is an alkyl group, for example having 1-6 C atoms, such as methyl, or a CR8R9 group wherein R8 and R9, which may be the same or different, are each a hydrogen atom or an alkyl group, for example having 1-6 C atoms, such as a methyl or hydroxyl group or alkoxy group, e.g. with 1-6 C atoms, such as methoxy, with the proviso that two or more hydroxy or alkoxy groups of formulas R3-R6, R8 or R9 must be bonded to different carbon atoms and that, when n is 2, at least one Y group is a CR®R9 group.

Thus, the divalent aliphatic group having the two free valences spaced two atoms may have 2-6 C atoms, such as a 1,2-ethylene group -CH2-CH2 or -1,2-dihydroxy -ethylene group -CH (OH) -CH (OH) -. The divalent aliphatic group with the free valences spaced at three atoms may have 3-10 C atoms such as a 1,3-propylene group, optionally with at least one hydroxyl or alkyl (such as methyl) or methoxy substituent, e.g. carbon atom # 2 or 3, such as in the groups -CH2-CR®R9-CH6, wherein R® is hydrogen or methyl, R9 is hydrogen or hydroxyl or methyl, and R6 is hydrogen or methyl or methoxy. The divalent aliphatic group with the free valences spaced at 3 atoms may also have 2-6 carbon atoms and the formula -CHR3-O-CHR5 or -CHR3-NR7-CHR5- wherein R3 and R5 are as defined above, but preferably hydrogen atoms.

The divalent aliphatic free valence group spaced 4 atoms may have 4-10 carbon atoms, for example a -1,4-butylene group, optionally with at least one hydroxyl or alkyl (e.g. methyl) or methoxy substituent.

In another type of methylolated cyclic urea, the aforementioned groups R 1 and R 2 form a tetravalent aliphatic group such that together with the nitrogen atoms and carbonyl groups of two ZN-CO-NZ groups form two condensed 5-, 6- or 7 - led rings. Such tetravalent groups usually have the formula -CR3- (Y) n-CR3 - wherein R3, R5, Y and n are as defined above. Preferably, n is 0 and the group is the acetylenyl group of the formula -CH-CH-.

30 I I

Examples of the methylated cyclic ureas are dimethylol-ethylene urea and especially 1,3-N, N-dimethylol-4,5-dihydroxy-ethylene urea, but also dimethylol - propylene urea and its 4-methoxy-5.5 -dimethyl and 5-hydroxy analogs and the 5-oxa and 5-alkylimino analogs of dimethylol-propylene urea and tetramethylol-acetylene diurea.

5 DK 171776 B1

The substance containing the cured THP polymer is impregnated with an aqueous solution of the methylolamide, for example, a solution containing 40-250 g / ml. liter, such as 80-180 g per liter. liter, in particular 110-180 g per liter. per liter of methylolamide, at a acidic pH of less than 3, for example 1-2 or especially less than 1. The pH of the solution of methylolamide is usually adjusted with an acid, especially for low temperature cure, for example at less than 50 ° C. Inorganic acids such as hydrogen chloride or especially sulfuric acid are preferred. The greater the amount of acid added, the higher the cure rate or the higher the cure rate. The impregnation solution is usually 0.1-10, for example 0.5-10, especially 1-6, such as 1-4 or 4-6 normal to acid. The solution may contain added solution salts, for example of mono-, di- or trivalent metals and anions from strong acids, such as chlorides, nitrates and sulphates, in amounts of 2-200, for example 2-50 or 10-200 g per liter. liter, for example 10-70, such as approx. 50 g per liter. Examples of salts are salts of ammonia, for example ammonium chloride, alkali metals, alkaline earth metals such as magnesium and zinc and aluminum, and the salts can increase the cure rate. The amounts of zinc salts, for example zinc nitrate, may be 2-20 g / ml. liters and amounts of magnesium salts, for example magnesium chloride, of 10-50 g per liter. liter. The solution may contain a wetting agent, such as a nonionic and / or anionic agent, in an amount, e.g. per liter of the solution, and may also contain an optical brightening agent, stable to the acidic conditions, for example in an amount of 10-30 g per liter. liters of the solution.

Particularly for high temperature cure, for example at above 50 ° C, the dissolved salts described above can be used in the aqueous methylolamide solution to obtain acidic solutions in water, especially when the pH of the impregnated solution is adjusted to 2- 6, for example, 3-6.

A water-soluble carboxylic acid, for example with 2-6 C atoms and usually 1-3 hydroxyl groups, such as glycolic, cis-, apple, lactic, tartaric and almond acids, can be used in amounts of e.g. 3-100 g per liter, such as 10-70 g per liter. per liter as well as or in place of the above-mentioned soluble salts by such processes.

5 The fabric is impregnated with the solution and the wet fabric is usually pressed to absorb moisture of 50--120%, for example 60-90%, (based on the dry weight of the ΊΉΡ-cured fabric). Alternatively, the solution can be applied by a minimum addition technique, giving a 10 absorbance of only 10-50%. The dry weight uptake of the methylol amide is usually 3-20%, for example 6-20%, such as 7-15% (calculated on the same basis). The substance can then be cured when it has a moisture content of 6-90%, such as 30-90%, for example, after the above pressing, or when it has a moisture content of 6-30%, for example the substance after minimum addition as such or after drying, or the pressed fabric after partial drying.

The moisture content of the substance at the beginning of curing can be calculated from the weight of the impregnated substance at that time, the initial weight of the substance and its moisture content (obtained from the weight loss upon drying), the concentration of solids and water in the impregnation solution and the moisture uptake.

The presence of the aqueous solution on the substance 25 causes it to swell and then the substance reacts during the cure with the methylolamide to form a cured substance wherein the methylolamide is cured on the substance, for example, by binding to the cellulose, for example by cross-linking the cellulose, and / or bond to the cured THP polymer. Vanishing medium is present on the fabric throughout the cure, so that at the end of the cure there is a cured substance, impregnated with aqueous medium, and therefore still swollen. Such a cure may be called a moist or wet cure as opposed to dry cure in which the wet impregnated substance is dried to remove its moisture and produce an impregnated dry matter which has sunk together, and then carried out the hardening of this dry substance.

If the moisture content of the substance at the beginning of curing is 6-30%, the aqueous solution of methylol amide impregnated on the substance usually has a pH of 5 to 1-3, preferably 1-2. The substance is usually allowed to stand at a temperature of less than 50 ° C, for example 10-40 ° C, and preferably at ambient temperature, such as 15-40 ° C, for 5-50 hours, such as 10-30 hours and especially 15 ° C. 30 hours while taking precautions not to allow the moisture content to be changed beyond the above mentioned range, 6-90%, but preferably 6-30%, for example, by sheathing it into a plastic layer. If desired, the substance can be cured at 50-180 ° C from 1 minute to 6 hours, for example at 90-140 ° C for 2-20 minutes, although temperatures of 140-15-180 ° C can be used, again in all cases. having taken reasonable precautions to keep the moisture content within the above range throughout the curing, for example, with vapor curing in a chamber, if necessary under pressure, and preferably with saturated vapor. During these higher temperatures, the pH of the solution on the substance may be 2-6, preferably 3-5 for substances to be heated to, for example, above 90 ° C, and 2-3 for substances heated to 50-90 ° C. The time, pH and temperature are usually chosen to maximize the cure rate, but minimize any rubbing of the substance under the acidic time and temperature conditions.

If the moisture content of the fabric is 30-90%, for example 30-60% or 40-75%, such as 45-65%, at the beginning of curing, then the pH of the aqueous impregnating solution on the fabric is usually less than 1, and the substance is allowed to stand for a period of time and at temperatures and under conditions which are otherwise within the ranges specified for curing more dry matter. The moisture content is kept within a range of 6-90%, for example an interval of 30-90%, during curing. If a large amount of acid has been added to the impregnating solution, for example to obtain an acid strength in the bath of 3-10 N, such as 4-6 N, then the curing times can be reduced from 1 minute to 5 hours, such as from 0.5 to 4 hours, at ambient temperature, such as 15-40 ° C.

5 The fabric can be cured without externally applied tension or compression. Preferably, the impregnated fabric is cured in tension in at least one of the warp and weft directions, for example, the stresses resulting from externally applied forces and / or from internal forces in the fabric. Thus, by a continuous method in which impregnated fabric is sent from the impregnation bath, preferably through a press roll, and thence to a sand bar for curing, the fabric can thus be wound on the sand bar during a move which is at least sufficient to prevent the fabric preferably, this feature is retained substantially in the fabric of the sand bar during curing. This feature can even be increased during curing. The impregnated fabric can also be applied to the high-voltage sand boom, which is at least preserved during curing, but preferably applied to the fabric below the minimum 20 required to prevent the fabric from slipping. If the impregnated fabric is not dry, it is preferably advisable to take precautions during curing to prevent the discharge of the liquid through the roll, for example by rotating the roll slowly without any apparent loss of moisture. If desired, the fabric can be rolled again to reduce retained stresses in the fabric. The fabric is also usually cured when it is not curled unless a special effect is required, such as pleating. In a high-speed curing process, for example, with a cure time of less than 30 minutes, curing can take place in a vapor chamber under tensile conditions, again preferably under a minimal cushion to prevent the substance from being released.

After curing, the fabric is rinsed, neutralized and rinsed prior to pressing and drying. The addition of solids 35 in the resin treatment is usually 1-6%, especially 2-4%.

9 DK 171776 B1

The flame retardant property of the substance is not usually significantly affected by methylolamide post-treatment, but the substance's irrigation properties are often significantly improved. Thus, compared to the THP-cured substance prior to methylolamide treatment 5, the treated substance usually has reduced shrinkage, higher permanent-press value, greater wet curl angle, greater moisture recovery (equilibrium moisture content) and lower moisture absorption (retained water by centrifugation) and may have improved dry curl angle, especially if the curing of methylolamide is carried out under tension. The rates of retention of tear strength and abrasion resistance in the treated substance, as compared to the pre-treatment THP, are usually much higher than those found in the treated substances in which the THP has been treated with methylolamide and heat treated, and accordingly, the substances treated by the process of the invention may have a longer life than the latter with the heat treatment.

In a less preferred alternative process 20, the original substance can first be treated with the methyl amide and reacted, then treated with the THP compound or condensate and cured afterwards. In this process, a substance which has been reacted with a non-self-condensing methylolamide is treated with at least two methylol groups 25 (optionally alkylated) under aqueous acidic conditions at a pH of less than 3, thus treated with a tetrakis (hydroxymethyl) phosphonium compound or condensate thereof, which is then cured.

The nature of the methylolamide and its impregnation solution and its pH, and the impregnation and curing technique of the substance are substantially the same as that of the corresponding methylolamide treatment of substance already carrying a cured THP polymer, except for the hydrogen uptake of methylolamide impregnated substance. which is usually 50-120%, for example 60-110% (based on the dry weight of the substance), dry weight - the uptake of methylolamide which is usually 4-25%, for example 6-18%, such as 8- 14%, (calculated in the same way) and the moisture content of the substance at the beginning of curing, which may be 6-30%, but in particular is 30-90%, for example 30-60%, or 45-80%, but preferably 60-90 %, especially 70-90% (calculated on the initial weight of the substance), with such higher initial moisture content allowing the THP treatment to more effectively provide substances with better fire retardant properties than those obtained with substances, cured with the record hylolamide under humidity conditions of 6-30%.

10 Compared to the methylolamide wet-cured fabric, post-THP treatment dramatically increases flame retardancy and can also increase wet and dry curl angle, increase moisture recovery (or equilibrium moisture content after conditioning), and decrease moisture content after centrifugation (water soaking). Compared to fabric containing THP-cured polymer, the pre-methylolamide-cured post-THP-cured substance usually has reduced shrinkage after washing and increased wet and dry curl angle.

Compared to the properties of substances from curing 20 with methylolamide before ΊΉΡ treatment, the properties of substances from curing with methylolamide after THP treatment are generally better, especially the shrinkage of cured substances is often less than that of cured substances.

In both U.S. Patent No. 3,421,923 and in American 25 Dyestuff Reporter, Jan. 1976, pages 33, 34 and 63, a method of combustion of cellulose substances is described by a two-step process in which one of the two steps is a treatment with a tetrakis (hydroxymethyl) phosphonium compound or a condensate thereof, followed by 30 of curing with ammonia to a polymer, and the second of the two steps is an impregnation with a self-condensing methylolamide having at least two methylol groups, followed by reaction under aqueous acidic conditions.

However, although two treatment steps are performed in conjunction with the present invention in conjunction with the substance, these steps may, however, be carried out in any order.

11 DK 171776 B1

According to the US document, the material is first impregnated with an aminoplastic resin, e.g. a melamine / formaldehyde product, and then impregnated with a THP compound. During the discussion of the prior art in the US script, cf.

5 of its column 2, lines 22-33, drawbacks are highlighted by first using the THP step.

Furthermore, it should be noted that the U.S. Patent Specifies the "non-THP" material as aminoplast and lists several amine / formaldehyde products as suitable. In contrast, the material used according to the invention is limited to methylolamides in that it has been found that only methylol amides and specific derivatives thereof are suitable for the purpose.

The American Dyestuff Reporter article, in contrast, discloses a first impregnation step with a THP compound, followed by a second, separate treatment with e.g. N-methylol crosslinking agents. The article does not imply, neither explicitly nor implicitly, that the order of treatment may be reversible, with emphasis being placed on upgrading flame retardant properties for pre-existing THP-treated 20 substances by so-called "topping".

It should be further noted that the above article states that the pH of the "topping" baths is a critical factor affecting the physical properties such as tear strength and curl obtained for the relevant treated substances, and more specifically, lowering the pH to below 6.5-6.8 in the "topping" baths causes a significant deterioration of such properties. However, it has been found that the process of the invention can be carried out and actually preferably carried out under aqueous, acidic conditions, i.e. at a pH below 3.

To reduce the loss of tear strength in the treated substance compared to THP substance or native substance prior to treatment, a fabric softener, before or after the final drying step, can be added to an amount of 0.1-5 % by weight (based on the weight of the substance). Examples of such plasticizers 12 are B1 condensation products of fatty acids, for example with 8-20 C atoms, and polyamines or cyclization products, each in the form of protonated or quaternary salts thereof, and also quaternary ammonium salts with 2 fatty aliphatic groups, for example, 8-20 alkyl, and 2-short-chain alkyl groups, for example, with 1-6 C atoms such as methyl.

It is also recognized that with the THP-cured methylolamide-cured substance, regardless of the order of treatment, a mechanical shrinkage, e.g., mechanical compression shrinkage of the fabric, and significantly a progressive shrinkage of the fabrics after many repeated washings. This compression shrinkage usually involves the following steps: wetting the fabric with water and / or steam to form a swollen fabric, adjusting the width of the swollen fabric to the desired size, compression shrinking the fabric, and drying the fabric. The compression shrinkage can be done by intimate contact with a stretched elastomeric blanket and maintaining this contact, while reducing the elongation of the blanket, for example to 0. Drying can be achieved under boundary conditions, for example by pressing the damp, crimped fabric between a heated metal cylinder and a absorbent dust zone. Finally, the fabric can be plated or rolled. An example of such a process is the sanforized process described in International Textile Bulletin Dyeing / Printing / Finishing 2/86 p.

14, 16, 20, 22 and 27. The result of the combination of the steps of methylolamide treatment after or before THP treatment, followed by the mechanical shrinkage, is that the difference in dimensions, for example in the chain direction, between the dimensions of the finished substance and the dimensions after a wash may be small, for example less than 2.5% or 2%, or very small, for example less than 1%, and the degree of progressive shrinkage thereafter at later washing, for example, 50 times, may be small. for example less than 5%, or very small, for example less than 2 or 1%. If the mechanical shrinkage degree applied to the fabric is more than sufficient to compensate for the shrinkage by washing the fabric, the THP and methylolamide-cured fabric after mechanical shrinkage may extend to a wash with 5 e.g. up to 5%, and the degree of expansion can remain substantially unchanged over the next 50 times of washing, so that the degree of progressive shrinkage is extremely small. If desired, the mechanical shrinkage treatment can be carried out in the post-methylolamide treatment process after THP cure 10 and before the methylolamide reaction, instead of or as well as after the latter reaction, or, in the premethylolamide treatment process, before THP cure and after methylol -amide reaction instead of or as well as after the latter reaction. The mechanical shrinkage treatment is usually performed after the last curing step, whether it is methbylolamide or THP curing, and can be performed between the curing steps. If no mechanical shrinkage is performed, the methylolamide is preferably applied after THP, the treated substance provided having a tendency to have reduced shrinkage compared to substances treated in the reverse order.

The fabric usually contains most cellulosic fibers and preferably contains 100% cellulose, preferably as natural cotton, but also as ramie, flax or recycled fibers such as viscose or cuprammonium rayon fibers. The substance may have been mercerized with aqueous base or aqueous ammonia, optionally with amines, after or preferably before application of the THP compound. The cellulose fibers are especially woven, but can be knitted. They may also be blended with an amount, for example a minor amount, for example up to 50%, such as 1-50% concurrently miscible fibers, such as polyester fibers, for the production of, for example, blends of 60-80% cotton and 20-40% polyester . However, in particular, the method can be applied to substantially completely cellulose-like fibers, especially cotton. Prior to THP treatment, the substance may have a weight of 0.05-1.00 kg per day. m2, such as 0.1-100 kg per square meter. m2, usually 0.15-0.40 kg per square meter. and preferably from 0.23 to 0.37 kg per square meter. m2. Examples of such fabrics are cotton sweater or bedding, shirting or curtain fabric.

The substance prior to THP or methylolamide treatment may have been stained, for example with tint or azo dyes, although basic, reactive, direct, acidic or dispersion dyes may also be used. If the fabric is to be dyed after THP treatment, reactive dye vests are preferred. If the fabric is to be dyed prior to methylolamide treatment, then dyes, such as quince and azo dyes, are preferred. Thus, with cap or azo dyes, the fabric is stained, treated with THP compound and cured and then treated with methylolamide and reacted therewith. Alternatively, with some shades of cape or azo dyes, it may be better to treat and react with methylolamide first and then color, and then treated with THP compound and then cured.

The treated substances with flame retardant and iron-light properties can be used for uniforms, for example for security guards and for the fire corps and for work clothes. Lighter fabrics can be designed for uniform shirts, for which permanent-pressure values and iron-light properties are especially important, and more powerful fabrics, such as cotton sweaters 1-25 fabrics, can be designed for work clothes, such as overalls and trousers, for which the lack of shrinkage is particularly important. important.

The invention is illustrated in the following examples, using the following test methods. In each case, the substance is conditioned to 20 ° C and 65% relative humidity for 30 hours prior to testing.

1. Curl

Both dry and wet curl angle, as compared to the untreated substance, are measured using MONSANTO WRINK-35 LE RECOVERY TESTER with a load of 500 g and 3 minutes load per day. curl per once, in the chain direction and curled 15 DK 171776 B1 with the surface facing outwards.

2. Permanent Pressure Value (D.P.) In Examples 1-15, the substance is evaluated using 5 of AATCC Test Method No. 88 iron-free standards and DP values, based on the smooth appearance of the fabric, compared to standard values 1-5 (with 1 being the worst value), while the test method of Examples 16-26 is AATCC Test Method 124.

3. Shrinkage Chain and shot shrinkage is measured according to the method of BS 4923 (1973) after the fabric has been washed 40 times (in Examples 1-15) or 50 times 15 (in Examples 16-27) in that manner. which is described in DIN 53920 with soft water) at 93 ° C.

4. Strength 20 Tensile strength is measured according to BS 2756 and the tear strength in the firing direction (according to Elmendorf) is also determined.

5. Flame retardant

The flame retardant property of the fabric is tested in the post-treated condition, after 12 times washing at 93 ° C and after 40 times washing at 93 ° C (in Examples 1-15) or 50 times (in Examples 16-26), the way described in DIN 53920 with soft water). The test method used is according to BS 3119.

6. Analytical determinations of the substance% P,% N and ppm formaldehyde are determined on the substance in the post-treated state. % P and% N are also determined after 12 and 40 times washing (in Examples 1-15) or 50 times washing (in Examples 16-19) at 93 ° C. The atomic ratio of N to P is calculated.

16 DK 171776 B1 7. Wear resistance

The accelerator test is performed according to AATCC-99-1984, Method A, and involves abrasion with a 250 mesh canvas rotating for 3 minutes at 3000 rpm and determination 5 of the weight loss.

THP hardened substance

Substance A

For use in Examples 1-13, 15 and 27, the 10 THP-cured fabric is obtained by impregnating 3111 cotton swirl1 fabric weighing 0.285 kg / kg. m2, which has been previously stained with highly visible orange azo color and not sanitized, with an aqueous solution at a pH of 4.5 of a precondensate of THP chloride and urea in a molar ratio of 1: 0, 5 and an amount in solution corresponding to 25% THP ion to a ca. 80% hydrogen uptake, drying the impregnated substance at 120 ° C for 1 minute and then curing with gaseous ammonia in a pressurized ammonia processor as described in U.S. Patent No. 4,145,463. The cured substance is oxidized with hydrogen peroxide, neutralized with sodium carbonate solution, rinsed and dried.

Substance B. C. D οα E

The procedure specified for substance A is used for the four other cotton fabrics with the following change: The rinse water includes a fabric softener ("Alkamine" FPS) in an amount of 2% by weight of the THP-cured substance and each of the THP-cured substances the compression is then mechanically shrunk according to the "Sanforization" method. The fabrics 30 are mercerized chain satin for work clothes weighing 0.270 kg per piece. m2, pre-tinted blue (fabric B), azo-red 3111 screw with a weight of 0.346 kg / m2 (fabric C), azo-red 3113 chain satin screw with a weight of 0.28 kg / m2 (fabric D) and 3117 twill fabric with a weight of 0.192 kg / m2 35 and optical mains (substance E).

17 DK 171776 B1

Example 1 Lengths of THP-cured substance A are fouled to 80% moisture uptake with an impregnation solution containing 250 ml of a 45% aqueous solution of di-1,3-N, N-methyl-4,5. -dihydroxyethylene urea (DMDHEU) sold under the trade mark "FIXAPRET CPN") per per liter and 50 ml of 98% sulfuric acid per liter. a pH of less than 1 and an acid concentration in the bath of 1.88 N. The wet, fouled substance with a total moisture content of approx. 68% (based on the weight of the THP-cured fabric) is folded carefully and placed in a polyethylene bag which is then sealed and kept under relaxed conditions (i.e., no draft) for 22 hours at room temperature to hardening. The substance is then removed, washed successively with cold 15 water, 10 g / ml. a liter of aqueous sodium carbonate, an aqueous solution at 50 ° C containing 2 g of sodium carbonate per liter. liter and 2 g of detergent per liter. liter, hot water at 60 ° C and cold water. The substance is then dried and then tested for comparison with samples of the THP-cured substance (compare A).

The results are as follows.

18 DK 171776 B1 (¾ ^ o

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Example 2

The procedure of Example 1 is repeated with the following changes: The impregnation solution also contains 0.5 g of a wetting agent, which is a mixture of nonionic 5 and anionic wetting agents sold under the WA100 mark by Brookstone Chemicals Staffordshire, England, per after curing, the substance is washed in cold water, neutralized with sodium carbonate solution, rinsed with cold water and dried at 100 ° C. Square pieces of the provided 10 fabric and square pieces of the original THP-cured fabric are washed in a washing machine at 60 ° C for 10 minutes, then rinsed three times with cold water and centrifuged for 4 minutes at 1000 rpm. minute. The fabric squares are then dried using cloth clips on a string 15 at room temperature or dried in a tumbler for 15 minutes with a maximum final temperature of 70 ° C.

The fabric squares are tested for permanent-press value compared to squares of THP-cured fabric (Comparative Example B). The results are as follows.

20 DP value

Fabric Dryer Dryer

Example 2 4-5 3-4 25

Compare. B 2 2

Example 3 For Example 3, the procedure of Example 1 is repeated with the following changes: The impregnation solution of pH less than 1 contains 70 ml of concentrated (35%) hydrochloric acid (instead of sulfuric acid) per ml. to give an acid concentration of 0.82 N, and also contains 0.5 ml of wetting agent as in Example 2 per liter. liter and allowed to cure for 16 hours. The moisture content of the substance at the start of curing is approx. 72% (based on the weight of THP cured substance).

DK 171776 B1

The tests on the properties of the substances are performed and the results are compared with the results for the THP-cured substance (Comparative Example C). The results are as follows: 5 Curl angles (degrees) Wet Dry

Example Chain Shots Chain Shots

Compare. C 95 85 91 89 10 3 139 131 92 88

Shrinkage (%)

Example Chain Shots 15 Comp. C 8 2.5 3 4 0.5

Flame retardant (according to BS 3119) 20 Example Average carbon lining (mm)

After- After 12 After 40 treated, the wash is washed the wash is washed 2 5 __________

Compare. C 70 69 53 3 70 70 54 30

Analysis

Example After- After 12 After 40 Treated, Washing is Washed, Washed 3 5 __-_

% P% N HCHO ppm% P% N% P% N

Together C 3.07 3.22 300 2.87 2.80 2.74 2.72 40 ______ 3 2.91 3.50 320 2.75 3.15 2.70 3.13 21 DK 171776 B1

Examples 4-12

The procedure of Example 1 is repeated with a variation of amounts and proportions of the curing agent and added concentrated sulfuric acid. In each case, the moisture uptake from the resin impregnation bath is set to be approx. 80% and the moisture content of the substances at the start of curing is from approx. 63 to approx. 72%, based on the weight of the THP-cured substance. The results are as shown below.

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Example 13

The procedure of Examples 7-9 is repeated, replacing the amount of sulfuric acid with 100 ml of concentrated hydrochloric acid (about 35% by weight) to give a solution 5 having a pH value less than 1 and an acid concentration of 1, 17 N. The moisture content of the substance at the start of curing is about 71%, based on the weight of the THP cured substance. The treated substance is tested for abrasion resistance according to the accelerator rotor test and the weight loss is found to be 10.6%. The results of the other samples are as follows: Chain shrinkage 3.5%, wet curl angle 150 °, tear strength (Elmendorf, shot) 1.10 kg, average FR ball length after 40 times washing: 6 8 mm.

Example 14

The procedure of Examples 7-9 is repeated with the following changes: THP hardened substance B, and in the impregnation bath 140 ml of concentrated sulfuric acid per ml. liter (giving a solution with an acid concentration of 5.25 N) with a cure time of 3 hours. The moisture content of the substance at the start of curing is approx. 57% (based on the weight of THP hardened substance). The results for the treated substance are as follows, compared to the results for the THP substance B before treatment.

25 Carbonization Wet curl angle Tear length (mm) in °, chain strength after 40

Ex. Elmendorf, N times washing 30 14 150 20,712 56

Sammen1. 90 29,185 52

Example 15 The procedure of Example 14 is repeated with THP- cured substance A. The results for the cured substance are as follows, compared with the results for the THP substance A prior to treatment.

24 DK 171776 B1 Wet curl- Tear-FR-Focal-Wear-resistant angle strength ring length density in °, Elmen- (mm) after Accelera-

Ex. chain dorf N 40 times wash tor% 5 _ 15 140 10,356 70 11.0

Comparison 95 15.102 55 9.2 10

Examples 16-19 Lengths of 20 m of fabric A, 30 m of fabric C, 50 m of fabric D and 30 m of fabric E are sewn together and continuously passed twice through a foulard solution containing 350 g of the aqueous solution of DMDHEU, used in Example 1. 90 g of 98% sulfuric acid per liter. to give a pH of less than 1 and an acid concentration in the solution of 1.84 N, and 2 g of the wetting agent used in Example 2 per liter. liter. The excess foulard solution is pushed away from the swollen substances, which then, with moisture content of approx. 52 to approx.

60% (based on the weight of THP-cured substances) and under minimal tension to prevent the substance from being released, sent to a roller, wrapped in a plastic wrap and the roller rotates slowly at room temperature (18 ° C) for 22 hours to cure 25 of DMDHEU. The moisture uptake for each of the substances is A 72%, C 59%, D 72% and E70%. Each hardened substance is then washed with water, then neutralized and then washed again with water in a jigger coloring machine, followed by a softening step in which each of the four substances is passed three times through a soaking bath at 40 ° C containing 10 g of a non-ionic fatty ester derivative plasticizer sold by Crosfield Textile Chemicals as "CROSOFT XME" per liter.

The wet substance is then sucked dry and then dried by heating to 150 ° C in a tension frame to give Treated Fabrics 35.

The four substances obtained are then tested with results as follows, comparing the properties of substances A, C, D and E with the Treated Substances A, C, ie. before and after the DHDMEU treatment.

1. Shrinkage Chain and shot shrinkage is determined as described above, but after 50 times washing.

Example Fabric (%) Chain (%) Shot 10 A 13.2 6.0 16 Beh. A 5.5 4.0 C 979 5ΤΪ 17 Beh. C 4.0 4.3 15 _ 8.0 6.3 18 Beh. D 2.7 4.6 E 5/7 7ΤΪ 20 19 Beh. E 3.6 4.2 2. Tear strength in the firing direction according to Elmendorf 25

Example Substance Strength (N) A 19.02 16 Beh. A 18.34 3 0 _ C 45.50 17 Beh. C 33.93 D 26.28 35 18 Beh. D 18.73 E 15.98 19 Beh. E 12.75 40 45 26 DK 171776 B1 3. Tensile strength according to BS 2756 for Treated Fabric and for Treated Fabric C only after 50 times washing at 93 ° C (according to DIN 53920 with soft water).

Example (Strength) N

Fabric Chain Shoe A Ϊ252 690 16 Beh. A 1030 619 10 _ C 1237 794 17 Beh. C 1179 609

Washed C 1251 800 15 17 Beh. C 1183 683 D 1145 T40 18 Beh. D 913 597 20 É 760 529 19 Beh. E 617 406 25 4. Flame retardant, tested as described above after 50 times washing.

Example Fabric Average Carbon Length A 52 30 16 Beh. A 56 _ - 17 Beh. C 56 35 D 58 18 Beh. D 68 _ - 19 Beh. E 79 40 _ 45 50 27 DK 171776 B1 5. Curl angles

Ex. Fabric Wet (°) Dry (°) 5 A ϊόό 90 16 Beh. A 145 105 C 95 130 17 Beh. C 145 135 10 _ D 95 95 18 Beh. D 145 110 É 95 ΪΪ0 15 19 Beh. E 145 130 6. DP value, as described above, of substances after a single wash at 95 ° C and drying as in Example 2.

Example DP Value

Fabric Dryer Dryer 25 A 2 2 ^ 3 16 Beh. A 3-3.5 3-3.5 C 2 2 17 Beh. C 3-3.5 3-3.5 30 _ D 2 2-3 18 Beh. D 3-3.5 3.5-4.0 _ _ _ 35 19 Beh. E 3 3-3.5 40 45 28 DK 171776 B1 7. Analysis results of Treated Substance before and after 50 times washing at 93 ° C (according to DIN 53920 with soft water)

Ex. Before Washing After Washing 5

Fabric% P% N% P% N

A 3.2 3.1 2.6 2.5 16 Beh. A 3.0 3.5 2.7 3.1 10 _ C 2.9 2.9 2.3 2.2 17 Beh. C 2.7 3.3 2.6 3.0 15 D 2.3 2.1 2.0 1.8 18 Beh. D 2.2 2.6 2.0 2.3 20 E 2.6 2.3 2.4 2.0 19 Beh. E 2.4 2.7 2.3 2.5 8. Colorfastness to lvs

25 The light resistance to a xenon arc is measured according to BS

1006, 1978, B 02. There are no differences between the results for substances A, C, D and E compared to the Treated Substances A, C, D and E.

9. Handle

There is no detectable difference between the handles of substances A, C, D and E compared to the Treated Substances A, C, D and E respectively.

35 10. Foot Content

The moisture content of substances A, CE and Treated Substances A and CE, respectively, is determined, each time after conditioning in 24 at 65% relative humidity, by drying the conditioned, pre-weighed substances for 2 hours 40 at 105 ° C. and then reweighting. The moisture content of the substances is approx. 0.5% less than for the Treated Substances. Thus, the treatment with DHDMEU increases moisture recovery at 65% relative humidity.

11. Water suction

Substances A and C-E and Treated Substances A and C-E 5 receive an HLCCl wash in a Servis Quartz machine and the water retained after the wet substances are centrifuged at 1000 rpm for 4 minutes is determined. The Treated Substances retain less water than the Substances. The treatment with DHDMEU reduces the water intake.

10

Examples 20-26 Fabric 200 m pieces 3111 swivel cotton fabric, in the condition it comes from the loom weighing 0.295 kg per piece. m2 is removed enzymatically, process washed with base and bleached with basic hydrogen peroxide. Of the bleached fabric weighing 0.27 kg per m2, four 50 m lengths are obtained, which are subjected to the process treatments W, X, Y and Z respectively (general details of which are given below), wherein the treatment steps and cure 20 with DHDMEU, treatment and cure with THP compound and mechanical compression shrinkage are carried out in various combinations. .

Beh. V X Y Z

25 _

First DHDMEU THP THP THP

step curing hardened. hearth. hearth.

30 Other - - Mek.

step shrinkage.

Third THP - DHDMEU DHDMEU

step curing - curing. hearth.

35

Fourth Mek. Mek. Mek. Mek. ' step shrink. shrinkage. shrinkage. shrinkage.

40 THP curing steps for the treatment lenses V. X. Y and Z

The substance is treated as described for substance 30 DK 171776 B1 A. The moisture uptake is approx. 80% for treatment V (based on the weight of DHDMEU cured substance) and 100% for treatments X, Y and Z (based on the weight of the bleached substance).

5 DHDMEU curing steps for treatments V. Y and Z

The substance is treated in the manner described in Examples 16-19 but with a foulard solution containing 325 g of the aqueous DHDMEU solution per ml. 90 g of 98% sulfuric acid per liter. 2 liters of wetting agent used in Example 2 per and 18 g of an acid stable fluorescent luminous moiety per liter. liter, sold by Sandoz as "Leucophor BCR" liquid. The moisture uptake is 100% for treatment V (based on the weight of bleached fabric) and 75% for treatments Y and Z (based on the weights of THP cured substance) and the moisture content of the substances at the start of curing is approx. 60% for example 20-24 (based on the weight of THP and fabric) and 79% for Examples 25 and 26 (expressed by weight of original fabric).

Mechanical Compression Requirements

The fabric is compression shrunk mechanically on a classic Sanforizer11 machine as described in International Textile Bulletin Dyeing / Printing / Finishing 2/86, pages 14, 16, 20, 22 and 27, which involves initial steaming, setting 25 of width, pressing against a stretched rubber blanket, which is then allowed to release, resulting in shrinkage of the fabric, followed by drying by pressing the fabric between a heated metal cylinder and an absorbent blanket, and rolling. , X, Y and Z.

Optical lens section

The optical brightening agent is introduced into the fabric as part of the DHDMEU impregnation in treatments V, Y and Z, but in the rinse water from the THP cure in treatment X.

31 DK 171776 B1

The results

The properties of the treated substances obtained in the fourth step of treatments V, Y and Z are tested, and the same happens with some of the properties of the substance from the last 5 steps of treatment X and previous steps in X, Y and Z .

In the table and results below, Examples 20-26 and Comparative Examples D-G refer to the substances obtained in accordance with the following treatments.

10

Example Substance Summary of _Trine Operation

21 3 Y THP, DHDMEU

15 22 3 Z THP, Mek. shrinkage.,

DHDMEU

23 4 Y THP, DHDMEU,

Mek. shrinkage.

24 4 Z THP, Mek. shrinkage.,

20 DHDMEU

Mek. shrinkage.

25 3 V DHDMEU, THP

26 4 V DHDMEU, THP,

Mek. krvmp.

25

Compare. D 4 X THP, Mek. shrinkage.

Compare. E 1 X THP

30 Comp. F - - Originally bleached fabric

Compare. G_1_V DHDMEU only

35 1. Shrinkage The chain and shot shrinkage is determined in the manner described in Examples 16-19 after washing 1 and 50 times.

40 32 DK 171776 B1% Shrinkage after a given number of wash cycles

Example 1 50 5 Chain Shots Chain Shots

Comp. G 1.2 2.2 2.3 2.5

Compare. F - - 12.8 5.6 10 Comp. E 3.9 3.5 12.4 8.8

Comparison 1.0 2.8 7.3 5.9 21 1.4 2.1 4.4 3.5 22 1.8 2.2 4.7 3.3 15 23 +2.9 1.6 +2.3 2.1 24 - - +2.3 1.8 25 2.0 2.4 6.3 4.0 26 _ + 3.1 2.1_ + 2.4 2.5 20 NB The sign "+", for example +2, 3%, means an expansion by washing rather than a shrinkage.

2. Tear strength in the firing direction according to Elmendorf 25 Example Strength (N) Chain Shot

Compare. D 29.42 29.42 23 21.57 21.57 30 24 24.52 23.54 26 23.54 21.57 3. Tensile strength according to BS 2756 35 33 DK 171776 B1

Strong (N)

Example Chain Shots

Compare. D 1262 751 5 23 1010 572 24 1012 575 26 1014 580 10 4. Flame retardancy tested as described above after 50 times washing.

Example Average length (mm)

Compare. D 60 15 23 62 24 67 26 53 20 5. Curl angles

Example Wet (°) Dry (°)

Compare. G 130 90

Compare. F 65 90 25 Comp. D 95 70 23 140 100 24 140 100 26 135 100 30 6. DP value, as specified above, after a single wash at 95 ° C and drying as in Example 2 35 34 DK 171776 B1 DP value

Example Dryer Dryer

Compare. G 3-3.5 3-3.5 5 Comp. F 1-2 1-2

Compare. D 2 2 23 3-3.5 3-3.5 24 3-3.5 3-3.5 26 3 3 10 _ 7. Moisture content

The moisture content of the fabrics is determined as in Examples 16-19, Part 10. The moisture content of the fabrics in Examples 23, 24 and 26 is higher than the moisture content of Comparative Example D with a size of 0.5-1% according to oven drying studies. The DHDMEU treatment therefore increases the moisture recoveries at 65% relative humidity.

8. Water Opsuanina 20 Moisture retention by centrifugation of wet substances is tested as in Examples 16-19, Part 11, the substances tested being the substances of Comparative Example D, Examples 23, 24 and 26. The substances of Examples 23, 24 and 26 retain 22 % less moisture than the substance of Comparative Example D. The DHDMEU treatment reduces water absorption.

Example 27 THP-cured substance A is fouled with an impregnation solution containing 250 ml of the 45% DMDHEU solution used in Example 1 per ml. 10 g of 98% sulfuric acid per liter. The solution has a pH of approx. 1.7 and an acid concentration of 0.2 N. The fouled substance is pressed to a 75% moisture absorption and then heated in an oven at 35 ° C for 3 minutes to give a substance containing 10% moisture. The fabric is immediately sealed in a plastic bag to maintain its moisture content and allowed to stand for 22 hours at room temperature under relaxed conditions. The fabric is then removed and washed as in Example 1. Finally, it is dried and then washed 50 times at 93 ° C. The chain shrinkage after that wash is tested and found to be 5%, compared to 10% 5 for the similarly washed THP-labeled substance A prior to DMDHEU treatment.

Claims (7)

A method of treating a cellulose textile material to make it both flame retardant and curl resistant by treating the material in two stages, one of which is an impregnation with a tetrakis phosphonium compound with subsequent curing with gaseous ammonia and the other is a impregnation with a non-self-condensing methylolamide having at least two methylol groups with subsequent curing, characterized in that the following two steps are carried out in random order: (i) treating a cellulosic fiber fabric such as cotton or a mixture of cellulosic fibers with polyester fibers , with an aqueous solution of a tetrakis (hydroxymethyl) phosphonium compound or a condensate thereof with urea, followed by curing with gaseous ammonia, and (ii) impregnating the substance with an aqueous solution of pH less than 3 self-condensing methylolamide, preferably a methylated cyclic urea, e.g. dimethylol-ethylenurea, 1,3-N, N-dimethylol-4,5-dihydroxyethylenurea, dimethylol-propylenurea, its 4-methoxy-5,5-dimethyl and 5-hydroxy analogs and the 5-alkyl-imino analogs of dimethylo-propylene urea and tetramethylol-acetylene urea, and subsequent wet curing of the substance while having a moisture content of 6% to 90%. Process according to claim 1, characterized in that the moisture content is 6-30%. Process according to claim 1 or 2, characterized in that the aqueous solution according to (ii) has a pH value of less than 1 and that the substance has a moisture content of 30-90%. Process according to claim 3, characterized in that the normality of the acid in the aqueous solution according to (ii) is in the range from 1 to 6. Process according to any one of claims 1-4, characterized in that the dry weight uptake of the methyl-DK 171776 B1 olamide on the substance is 6-20% and that the dry weight uptake of the tetrakis (hydroxymethyl) phosphonium compound or condensate on the substance is 8- 20%. Process according to any one of claims 1-5, 5, characterized in that the fabric during the impregnation step (ii) is kept under tension or tension in at least one of the longitudinal and transverse directions. Method according to any one of claims 1-6, characterized in that the fabric is subjected to mechanical compression shrinkage after the second treatment step. 15 20 25 30 35