BE664757A - - Google Patents

Description

  

   <Desc / Clms Page number 1>
 



  FORMALDEHYDE FIXATION PROCESS
ON CELLULOSIC MATERIALS
The present invention relates to a new process for fixing aldehyde to cellulose, cellulose esters or starch; it also relates to a new aqueous formaldehyde composition.



   In the known methods of fixing aldehydes, such as formaldehyde, cellulose, cellulose esters or starch, it is difficult to predetermine the quantity of formaldehyde fixed, nor to regulate it reproducibly. In addition, it is often necessary to employ concentrated solutions of formaldehyde with large amounts of acid, which tend to degrade the material being treated. Finally, these processes have a low yield, only a small part of the formaldehyde involved.

 <Desc / Clms Page number 2>

 being fixed on the support, such as cellulose, the rest being lost.



   It has already been proposed to fix on the cellulose a formaldehyde precondensate with an alkyl carbamate, such as methyl carbamate. In such a process, nitrogen from the precondensate binds to the cellulose, as evidenced by the appreciable increase in nitrogen of the treated cellulose while the untreated cellulose contains only a relatively small amount. low.-
The process of the present invention enables an aldehyde, such as formaldehyde, to be fixed on a lasting basis to cellulose, cellulose esters and starch, the fixed amount being easily adjustable and reproducible with accuracy. The process of the invention is efficient, economical and rapid and the aldehyde remains permanently fixed, and stable, even after numerous washes.



   The invention also relates to cellulosic fabrics ready for use immediately after washing, shrink-proof and wrinkle-resistant. These articles are obtained with a much less decrease in strength than that which is generally produced by the usual finishing or finishing resins employed for the same purpose.



   The invention makes it possible to obtain the aforementioned qualities on fabrics crosslinked with formaldehyde; these new fabrics do not retain chlorine or other impurities, and their color remains stable, even after repeated washing; they are resistant to mold.

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   Another object of the invention is to improve the strength of the paper in the wet state.



   The subject of the invention is also a novel formaldehyde composition, capable of being fixed, among other applications, making it possible to reduce the swelling of cellulosic tissues moistened by water or aqueous solutions, and more particularly of tissues. non-woven viscose rayon, more durable whiteness.



   According to the invention, starch, cellulose, cellulose esters or similar materials are treated with an aqueous medium containing one of the following constituents: (1) mixing an aldehyde with an alkyl carbamate or d aryl, (2) an alkyl or aryl aldehyde-carbamate condensation product, (3) a mixture of aldehyde with an alkyl or aryl aldehyde-carbamate condensation product. It is also possible to use alkyl or aryl carbamates containing an N-hydrocarbon substituent. After treatment of the material with the aqueous mixture, it is heated to a temperature sufficient to fix the aldehyde, but insufficient to allow substantial nitrogen fixation.



   The cellulose can be found, for example, in the form of cotton, alpha-cellulose, xegenerated cellulose or rayon, that is to say of cuprammonium rayon, viscose or paper.,
As cellulose esters, there can be used in particular cellulose acetate, aceto-butyrate or aceto-propionate.

   Aldehydes which are suitable for the invention are for example: formaldehyde, glyoxal, pyruvic aldehyde, glutaraldehyde, acetaldehyde, propionaldehyde, butyraldehyde or hydroxyadipaldehyde, the preferred aldehyde being formaldehyde,

 <Desc / Clms Page number 4>

 
Cellulose can be mixed with synthetic fibers such as polyesters, such as polyethylene terephthalate, acrylic fibers, such as polyacrylonitrile or acrylonitrile-vinyl chloride copolymer (85/15 or 15/85), the polyamides sold under the trade name of "Nylon", such as the polymer of hexamethylene adipamide, poly-propylene or the copolymers of propylene-ethylene, the fiber sold under the trade name of "Spandex", the copolymers of vinyl chloride-vinyl acetate ( 87/13 for example) or others.

   



   Regarding the choice of aldehydes, glyoxal is preferable to obtain high rigidity, to obtain less rigidity than with formaldehyde, it is preferable to use other aldehydes such as acetaldehyde or hydroxyadipaldehyde; it is also possible to use mixtures of aldehydes.



   The formula of the organic carbamate is: HN-COOR where R is an alkyl or aryl group. Thus, for example, methyl, ethyl, propyl, isopropyl, butyl, amyl, hexyl, octyl, decyl, dodecyl, cyclohexyl and octadecyl carbamates can be employed.



   Among the N-hydrocarbyl-substituted carbamates of formula RNHCOOR where R1 and R2 are alkyl or aryl groups; Suitable for the invention are, for example, the following substituted carbamates: methyl, ethyl, isopropyl or phenyl phenylcarbamates; ethyl para-tolyl-carbamate; methyl, ethyl, decyl or phenyl methylcarbamates; phenyl, methyl, ethyl ethyl carbamates etc. ; methyl dodecyl-carbamate,

 <Desc / Clms Page number 5>

 cyclohexyl butyl carbamate, ethyl or methyl diethyl carbamates, ethyl or methyl dimethyl carbamates, methyl diphenyl carbamate etc.



   Aryl carbamates and N-hydrocarbyl carbamates generally require higher activation temperatures than lower alkyl carbamates such as methyl or ethyl. Therefore, the use of the latter is generally preferable.



   As indicated above, an aldehyde-carbamate condensation product can also be employed. It is, however, preferable to employ a mixture of aldehyde and alkyl carbamate which requires a shorter processing time and gives rise to a more regular reaction. In addition, the use of the mixture makes it possible to avoid the cost of the preliminary preparation of an aldehyde-alkyl carbamate condensation product.



   When using an aldehyde-alkyl carbamate condensation product, it is important that the treated product is not heated below about 150 C, because at higher temperatures, for example of the order of 177 C, instead of the decomposition of the condensation product into ammonia, carbon dioxide and alcohol, nitrogen fixation takes place on the cellulose by the methylol group as in the processes already known.



   When using an aqueous mixture of aldehyde and carbamate, the latitude of the heating temperatures of the product to fix formaldehyde therein is much greater. Thus one can use temperatures between about 82 and 150 C or even reaching about 177 or 205 C.

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   Unless otherwise stated, the heating temperature of the product indicated is the actual temperature reached by the latter, determined for example by surface pyrometry or by infrared in the case of moving articles; it is obvious that this value corresponds to a necessarily higher temperature of the furnace or of the heat sources in the case of heating by radiation. This is because the binding reaction of methylol carbamate is slower than that of formaldehyde binding to cellulose. Preferable temperatures for heating the product are from about 82 to 150 C, and from about 93 to 205 C for cotton, to avoid degradation.



   Surprisingly, carbamate acts only as a carrier substance to promote the binding of formaldehyde to cellulose, without binding itself in appreciable amount.



   To promote the attachment of the aldehyde to the cellulose, at least 0.1%, and preferably 0.3% by weight of methyl carbamate in the aqueous solution or dispersion, or an equivalent molar percentage in weight of any other carbamate used. If a smaller amount of carbamate is used, it is difficult to control the amount of aldehyde attached to the cellulose and to facilitate reproducibility of the aldehyde attachment, it is preferable to use at least 0.5% of methyl carbamate, or its equivalent, in the aqueous system. Except men-. To the contrary, parts and percentages are all given by weight below.

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   Larger amounts of carbamate can be used, for example 1 to 5% or more of methyl carbamate in water, but there is no advantage in employing an expensive excess. A lower carbamate, such as that of methyl and / and ethyl, is preferably used.



   The aqueous mixtures of the invention contain the aldehyde in amounts generally between 1 and 8% but, if it is desired to bind relatively high amounts to the cellulose, up to 10% or 15% may be employed. %, and even more. It is preferable to use at least 3 moles of aldehyde per mole of carbamate, but up to 60, or even 100 moles, per mole of carbamate can be taken. It is generally preferred to employ low molar proportions of aldehyde, and one of the characteristic advantages of the present invention is precisely that it requires a less amount of formaldehyde in solution than in the previous processes, for the same amount to be fixed. In addition, the odor of formaldehyde is at the same time reduced.



   In the processing of cotton, alpha-cellulose, starch or paper, an aqueous solution containing 1.25 to 4.0 formaldehyde is generally used to fix 0.25 to 1.25% formaldehyde. on the treated product.



   For the treatment of rayon and cellulosic esters, the aqueous solution generally contains 2.5 to 8.0% formaldehyde, to fix 0.5 to 2.5% formaldehyde. It is of course possible, in both cases, to use a solution containing
1.25 to 8.0% formaldehyde, with a view to fixing 0.25 to 2.5%

 <Desc / Clms Page number 8>

 of formaldehyde on the product.



   When using the carbamate-aldehyde condensation product, preferably enough aldehyde is added to the solution so that the total aldehyde content, including that of the condensate, is at least 3 moles per mole of the pre-carbamate. smells in the condensate.



   The mixture of aldehyde and alkyl carbamate, such as for example formaldehyde and methyl carbamate, can be marketed in the form of an aqueous mixture, containing the two substances in the proportions indicated, or else the aqueous mixture can be relatively concentrated and intended to be diluted. with water in the desired proportion at the time of use. It is preferable, for reasons of stability, during transport or storage, that the mixture is neutral, but it can also be alkaline or acidic.



  The bath, through which the body to be treated is passed, is generally acidic with a latent acid catalyst. Among the acids and latent acid catalysts suitable for the invention, there may be mentioned formic or hydrochloric acids, chlorides, ammonium, magnesium, calcium or zinc, zinc nitrate or fluoroborate, or their mixtures. Since the catalyst is only used in small quantities, it can be supplied by a waste salt releasing an acid, such as ammonium chloride.
The aldehyde can also be fixed by means of carbamate as a carrier substance, in an alkaline medium, by employing catalysts such as sodium or potassium carbonates or bicarbonates.

 <Desc / Clms Page number 9>

 sium, soda or potash.

   However, in most cases, the use of acid catalysts is preferred. As indicated above, the alkaline catalyst can also be produced on the body to be treated. When the catalyst is added to the treatment bath, its proportion is generally 0.1 to 2% of the bath, but it can vary.



   The normal method of applying the aqueous mixture of aldehyde and carbamate is to pass the fabric, fibers or yarns through the mixture and then to wring out the impregnated products by means of pressure rollers to remove the impregnated material. excess solution. In the case of wires, the spools of wires can be passed through the solution, in a tank or an autoclave. A similar process can be used to process starch.



   Excellent results, well reproducible and superior to those of known methods, 3ont obtained with solutions containing at least about 0.5% of alkyl carbamate; Another resulting advantage is that the amount of fixed aldehyde can be adjusted simply by adjusting the amount of aldehyde present in the aqueous mixture.



   Of course, the aqueous mixtures according to the invention can contain any customary additives such as wetting agents, modifiers of the staying power of textiles, softeners, lubricants, polishes or others.



   It is preferable to use the formaldehyde as it is in the aqueous mixture, but other sources of formaldehyde can also be used, such as paraformaldehyde, trioxane or hexamethylene tetramine. In these last cases the total duration of the treatment is a little longer, because of the dissociation of these substances

 <Desc / Clms Page number 10>

 into monomeric formaldehyde. A formaldehyde / alkyl carbamate molar ratio of about 12.5 gives the best results from an efficiency standpoint. The process of the invention, which is simpler in its implementation than the previous processes, also has the advantage of avoiding the use of concentrated acid solutions, which are difficult to handle and liable to degrade the treated product.



   Another important advantage of the process of the invention,. is to allow the fixing of aldehyde with a reduction in the resistance of the cellulosic product, much less than that at. which give rise to the usual methods of finishing with resins 1; in these known methods a 40-50% decrease in initial strength is common and can even exceed 50%. According to the prior methods, it is then necessary to compensate for this decrease. increase resistance by strengthening unbleached products in an expensive manner.

   According to the method of the invention, the reduction in resistance generally only reaches 15 to 25% and rarely exceeds 30%. It can be assumed that this favorable result is due to the following three reasons: the low temperature of the drying, sufficient to fix the aldehyde, compared to the high temperatures of polymerization of the usual finishing resins, the low concentration of the catalyst employed, and the fact that it is not necessary to push the drying to a residual moisture level /. Excellent results are obtained by drying to a residual moisture content of 2 to 4%, measured with a resistance hygrometer. tance.

   But to obtain the best possible results, drying is pushed until complete desiccation of the treated product.

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   In addition to the process of the invention allowing the treated product, cellulosic, or mixed with synthetic fibers, to better retain its initial whiteness, it also makes it possible to greatly reduce the swelling capacity of cellulosic products. The latter trait is particularly characteristic of viscose rayon nonwoven fabrics, which thereby are made more stable from the standpoint of shrinkage.



   The invention will be better understood on reading several nonlimiting examples of its embodiments which follow.



    EXAMPLE EXAMPLE 1
In general, the threads woven into the borders of the household linen shrink more than the rest of the room. To remedy this drawback, a series of cotton threads for edging parts is treated in an autoclave with an aqueous mixture containing 1% of methyl carbamate, 0.5% of magnesium chloride hexahydrate, 0, 5% formic acid, 1.2% sodium chloride, 0.17% methyl polysiloxane oil (as, softener) and the amounts of formaldehyde given below.



  After treatment, the threads are dried at 93.3 ° C., then they are woven into the edges of the cotton pieces. The results expressed in Table I following t
 EMI11.1
 

 <Desc / Clms Page number 12>

 
 EMI12.1
 
<tb> TABLE <SEP> I
<tb>
<tb>
<tb>
<tb> Formaldehyde% <SEP> Nitrogen <SEP> (+)
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> Echan- <SEP> Report <SEP> they <SEP> in <SEP> they <SEP> in <SEP> they <SEP> in <SEP> Children <SEP> in <SEP> Shrink
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> tillon <SEP> molar <SEP> the <SEP> part <SEP> part <SEP> after <SEP> part <SEP> part <SEP> sement <SEP> of <SEP>
<tb>
<tb>
<tb>
<tb>
<tb> n <SEP> formalized.

   <SEP> processed <SEP> 30 <SEP> washes <SEP> processed <SEP> after <SEP> 30 <SEP> the <SEP> border <SEP>
<tb>
<tb>
<tb>
<tb>
<tb> hyde / carba- <SEP>, <SEP> washes <SEP> after <SEP> 30 <SEP>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> mate <SEP> from <SEP> washes
<tb>
<tb>
<tb>
<tb>
<tb> methyl
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 1 <SEP> 2.5 <SEP> 0.14 <SEP> 0.13 <SEP> 0.03 <SEP> 0. <SEP> 05 <SEP> 3.1%
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 2 <SEP> 5.0 <SEP> 0.28 <SEP> 0.30 <SEP> 0.05 <SEP> 0.05 <SEP> -0.2
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 3 <SEP> 7.5 <SEP> 0.56 <SEP> 0.56 <SEP> 0.07 <SEP> 0.07 <SEP> -0.8
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 4 <SEP> 10.0 <SEP> 0.77 <SEP> 0.72 <SEP> 0.

   <SEP> 08 <SEP> 0.04 <SEP> -1.9
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 5 <SEP> 12.5 <SEP> 1.13 <SEP> 0.95 <SEP> 0.07 <SEP> 0.07 <SEP> -1.2
<tb>
<tb>
<tb>
<tb> 6 <SEP> 2.5 <SEP> 0.16 <SEP> 0.16 <SEP> 0.04 <SEP> 0.03 <SEP> 1. <SEP> 6
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 7 <SEP> indicator <SEP> no
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> processed <SEP> - <SEP> - <SEP> 0.03 <SEP> 0.07 <SEP> 6. <SEP> 3
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> Average <SEP> for <SEP> the <SEP> children
<tb>
<tb>
<tb>
<tb>
<tb> processed <SEP> 0.058 <SEP> 0.052
<tb>
 (+) Border shrinkage or differential shrinkage is equal to 100 (L-1): L where L is the total width of the room and 1 is the width of the border.



  In Test No. 1 a pre-condensate of methyl carbamate and formaldehyde was used.



  If the methyl carbamate had been attached to the strands, the amount of nitrogen would have been at least 0.26% for sample 5 containing 1.13% formaldehyde in the strand.

 <Desc / Clms Page number 13>

 



  The strength retention of the treated yarns in this example is excellent and does not depend on the amount of formaldehyde fixed, as seen from the following table.



   TABLE 2
 EMI13.1
 
<tb> Echan- <SEP> Resistance <SEP> to <SEP> Retention <SEP>% <SEP> Break <SEP> of a <SEP> Retention <SEP>%
<tb>
<tb>
<tb> tillon <SEP> the <SEP> break <SEP>, <SEP> only <SEP> end
<tb>
<tb>
<tb>
<tb>
<tb> of the <SEP> Skein <SEP>
<tb>
<tb>
<tb>
<tb> 109.7 <SEP> m
<tb>
<tb>
<tb>
<tb> '** "
<tb>
<tb>
<tb> KK
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 1 <SEP> 142.4 <SEP> 76 <SEP> 2.35 <SEP> 69
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 2 <SEP> 135.7 <SEP> 72 <SEP> 2.41 <SEP> 71
<tb>
<tb>
<tb>
<tb>
<tb> 3 <SEP> 138.8 <SEP> 74 <SEP> 2 ', 42 <SEP> 71
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 4 <SEP> 143.3 <SEP> 77 <SEP> 2.43 <SEP> 72
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 5 <SEP> 143.3 <SEP> 77 <SEP> 2.55 <SEP> 75
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 6 <SEP> 119.3 <SEP> 64 <SEP> 2.30 <SEP> 68
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 7-control
<tb>
<tb>
<tb>
<tb> 186,

  4 <SEP> - <SEP> 3.37
<tb>
 The retention values are established in relation to bleached mercerized yarns, immediately before their treatment with formaldehyde-carbamate. If we calculate these values in relation to unbleached mercerized yarns (2.9 K for single end breakage),. state in which the resistance of yarns is generally measured, the retention of the yarns treated in this example is between 80 and 88%.

 <Desc / Clms Page number 14>

 



  EXAMPLE 2
Cotton threads are saturated in an autoclave with an aqueous mixture containing 0.5% chloride / magnesium hexahydrate, 0.5% formic acid, 0.3% methyl carbamate and the amounts 'indicated of formaldehyde. The strands are then extracted under vacuum and dried at 82.2 ° C. until residual humidity of 2 to 3%.



   TABLE 3.
 EMI14.1
 
<tb>



  Sample <SEP> Formaldehyde <SEP>% <SEP> Formaldehyde <SEP>% <SEP> Molar <SEP> ratio <SEP>
<tb>
<tb>
<tb> in <SEP> the <SEP> mixture <SEP> on <SEP> threads <SEP> degreased <SEP> Formaldehyde /
<tb>
<tb>
<tb> Carbamate
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 1 <SEP> 1.5 <SEP> 0.37 <SEP> 12. <SEP> 5
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 2 <SEP> 1.5 <SEP> 0.40 <SEP> 12.5
<tb>
<tb>
<tb>
<tb> 3 <SEP> 2.5 <SEP> 0.52 <SEP> 20. <SEP> 8
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 4 <SEP> 2.7 <SEP> 0.52 <SEP> 22.5
<tb>
 The amount of formaldehyde fixed is generally about 20 to 25% of that of the aqueous mixture.



  EXAMPLE 3
An aqueous mixture, containing 5% formaldehyde, 1% methyl carbamate and 1% magnesium chloride hexahydrate, is padded on a heavy fabric bleached at 55-60% moisture uptake. It is dried at 82.2 C to about 10% residual moisture content, and heated to temperatures and times.

   indicated below (Table 4)

 <Desc / Clms Page number 15>

   xsteau T A B L EA U 4
 EMI15.1
 
<tb> (2)
<tb>
<tb>
<tb> Tempe- <SEP> Duration <SEP> Formaldehyde <SEP> Nitrogen <SEP>% <SEP> Aspect <SEP> (1) <SEP> Shrinkage
<tb>
<tb>
<tb> erase <SEP> in <SEP>% <SEP> fixed <SEP> on <SEP> on <SEP> the <SEP> of <SEP> the <SEP> string
<tb>
<tb>
<tb>
<tb> <SEP> C <SEP> minutes <SEP> the <SEP> fabric <SEP> fabric <SEP> 5L <SEP> 20L <SEP> of <SEP> fabric <SEP> (1)
<tb>
<tb>
<tb>
<tb> 5L <SEP> 20L
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 104 <SEP> 5 <SEP> 0.52 <SEP> 0.07 <SEP> 4.0 <SEP> 3. <SEP> 5 <SEP> 4.3% <SEP> 4.1%
<tb>
<tb>
<tb>
<tb>
<tb> 127 <SEP> 3 <SEP> 0.47 <SEP> 0.08 <SEP> 3.0 <SEP> 4.0 <SEP> 2. <SEP> 8 <SEP> 2.5
<tb>
<tb>
<tb>
<tb>
<tb> 1490 <SEP> 2 <SEP> 0.50 <SEP> 0.08 <SEP> 3.

   <SEP> 5 <SEP> 4.0 <SEP> 2.4 <SEP> 2.1
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 1710 <SEP> 1 <SEP> 0.57 <SEP> 0.09 <SEP> 4.0 <SEP> 4.0 <SEP> 1.9 <SEP> 2.0
<tb>
<tb>
<tb>
<tb>
<tb> 1490 <SEP> 15 <SEP> 0.58 <SEP> 0.09 <SEP> 3. <SEP> 5 <SEP> 3. <SEP> 0 <SEP> 3. <SEP> 3 <SEP> 3. <SEP > 5
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> control <SEP> --- <SEP> 0.04 <SEP> --- <SEP> --- <SEP> 8.3 <SEP> ---
<tb>
 (1) Estimated on fabric washed 5 times (5 L) and 20 times (20 L) in a washing machine containing 3.6 Kg of fabric, at 40.6 C, then barrel-dried in an automatic clothes dryer . The appearance is estimated from the American standard A A T C C by a scale of 1 (bad) to 5 (the best).



  (2) Degreasing the fabric for 1 hour at 93.3 C with 0.25% soap flakes and 0.50% sodium carbonate, followed by thorough rinsing.



  EXAMPLE 4
An aqueous solution containing 2.5% formaldehyde, 1.0% methyl carbamate and catalyst was applied as indicated on a series of samples of a loose cloth of mercerized and bleached cotton at 60% content of. moisture uptake.

 <Desc / Clms Page number 16>

 The fabric is dried at 82 ° C, to about% residual moisture, then at 127 ° C for 3 minutes.



   T A B L-E A U 5
 EMI16.1
 4 \ ¯¯¯¯¯
 EMI16.2
 
<tb> (1)
<tb> Echan- <SEP> System <SEP> Formaldehyde <SEP> Nitrogen <SEP>% <SEP> Angle <SEP> Recovery
<tb>
<tb> catalytic <SEP> tillon <SEP> fixed <SEP> before <SEP> after <SEP> of <SEP> <SEP> (W + F)
<tb>
<tb> sage <SEP> sage <SEP> crumpled- <SEP> Wet
<tb>
<tb> ment <SEP>. <SEP>
<tb>



  Dry.
<tb>
 
 EMI16.3
 



  1 IMgC12.6H20 '0.?2 0.08 0.07 2520 2120
 EMI16.4
 
<tb> (1% <SEP> HCOOH
<tb>
 
 EMI16.5
 2 1% MgCl.6HO 0.70 0.05 0.08 2590 246 3 1ô HCOOH 0.70 0.02 0.02 2450 234 4 0.liu 'NH4C1 (2) 0.70 0.08 0.'10 2570 2420
 EMI16.6
 
<tb> Witness <SEP> --- <SEP> --- '<SEP> 0.02 <SEP> 0.04 <SEP> 127 <SEP> 159
<tb>
 (1) Degreased fabric, 1 hour, at 9303C with 0.25% soap shavings and 0.50% sodium carbonate; then rinse thoroughly.



  (2) Estimated - the bath is neutral - residual NH4Cl from the previous treatment on the fabric.



  Here too, only traces of nitrogen were found in the treated tissue, but it is important to note that there is also no carbamate immediately after heating. This may explain the mechanism of the reaction, the carbamate being obviously decomposed by heating. We have been able to confirm this observation on a large number. other samples.

 <Desc / Clms Page number 17>

 



  EXAMPLE 5
Bleached mercerized cotton threads are treated, in an autoclave, with an aqueous solution containing 2.5% formaldehyde, 1.36% sodium chloride, 0.5% magnesium chloride hexahydrate, 0.5% formic acid, 0.1% dimethyl polysiloxane oil and the indicated amounts of methyl carbamate, then dried at 82 ° C.



   TABLE 6
 EMI17.1
 
<tb> Sample <SEP> Molar <SEP> ratio <SEP> Carbamate <SEP> Formaldehyde <SEP>%
<tb>
<tb>
<tb> n <SEP> formaldehyde <SEP> from <SEP> methyl <SEP>% <SEP> fixed
<tb>
<tb>
<tb> carbamate <SEP> from
<tb>
<tb>
<tb>
<tb> methyl
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> 1 <SEP> 62.5 <SEP> 0.1 <SEP> 0.30
<tb>
<tb>
<tb>
<tb>
<tb> 2 <SEP> 20.8 <SEP> 0.3 '<SEP> 0.52
<tb>
<tb>
<tb>
<tb>
<tb> 3 <SEP> 8.9 <SEP> 0.7 <SEP> 0.76
<tb>
<tb>
<tb>
<tb>
<tb> 4 <SEP> 6.25 <SEP> 1.0 <SEP> 0.20
<tb>
<tb>
<tb>
<tb>
<tb> 5 <SEP> 2.5 <SEP> 0.5 <SEP> 0.33
<tb>
 EXAMPLE 6
Bleached mercerized cotton threads are treated, in an autoclave, with an aqueous solution containing 1.3% sodium chloride, 0.5% magnesium chloride hexahydrate, 0.5% formic acid, 0,

  1% dimethyl polysiloxane, 0.3% methyl carbamate and the amounts of formaldehyde shown in Table 7.



  Then dried at 82.

 <Desc / Clms Page number 18>

 



  TABLE 7,
 EMI18.1
 
<tb> Samples <SEP> Molar <SEP> ratio <SEP>: Formaldehyde <SEP>% <SEP>: Formaldehyde
<tb> Formaldehyde / car- <SEP> in <SEP> solution <SEP>: <SEP> fixed
<tb> bamate
<tb> @
<tb>
<tb> 2. <SEP> 5 <SEP> 0.3 <SEP> 0.05
<tb>
<tb> 2 <SEP> 7.5 <SEP> 0.9 <SEP> 0.24
<tb>
<tb> 3 <SEP> 12.5 <SEP> 1.5 <SEP> 0.40
<tb> 4 <SEP> 17.5 <SEP> 2. <SEP> 1 <SEP> 0.34
<tb>
<tb> 5 <SEP> 22.5 <SEP> 2.7 <SEP> 0.52
<tb>
 EXAMPLE 7
Mercerized cotton yarns are treated in an autoclave with an aqueous solution of the quantities of the substances indicated in Table 8 and dried at 93. One of these substances is a pre-condensate of 2.5 moles of formaldehyde with 1 mole of methyl carbamate, hereinafter referred to by the abbreviation MC-F.

   The aqueous solution also contains 0.5% polyethylene as a softener and 0.1% of the ethylene oxide-alkyl phenol condensate as a wetting agent.



   TABLE 8
 EMI18.2
 
<tb> Substances <SEP> Samples <SEP> n
<tb>
<tb>
<tb> 1 <SEP> 2 <SEP> 3 <SEP> 4
<tb>
<tb>
<tb>
<tb> MC-F <SEP> 4% <SEP> 8% <SEP> 4% <SEP> 4%
<tb>
 
 EMI18.3
 v1gC12H20 1%, bound -, 1.5%
 EMI18.4
 
<tb> Zn (BF4) 2 <SEP> - <SEP> - <SEP> 1%
<tb> HCOOH <SEP> 1% <SEP> 1% <SEP> 1.5% <SEP> 1%
<tb>
<tb>% <SEP> CH2O <SEP> fixed <SEP> 0.63% <SEP> 1.93% <SEP> 1.02% <SEP> 0.78%
<tb>
 Nitrogen fixed in the wires is not found.

 <Desc / Clms Page number 19>

 



  Example 8
The tests relate to bleached mercerized yarns, as well as to bleached carded cotton yarns, treated in an autoclave with an aqueous solution containing 2% of a precondensate of one mole of methyl carbamate with 2.5 moles of formaldehyde. , 2.1% free formaldehyde, 0.5% magnesium chloride, 0.5% formic acid, 2.5% sodium chloride, 0.2% sulfonated tiller oil (as a softener) and 0.025% dimethyl polysiloxane. After drying at 93 C, the mercerized yarns contain 0.72% and the carded yarns 0.70% fixed aldehyde.



  Example 9
Mercerized cotton threads are treated in an autoclave, with an aqueous solution containing 0.5% of ethyl carbamate, 2.1% of formaldehyde, (i.e. formaldehyde / carbamate molar ratio =
12.5), 0.5% magnesium chloride and 0.5% formic acid. The threads are dried at 93.3 C to fix the formaldehyde.



   The following examples show the effectiveness of the method of the invention in reducing tissue swelling; therein describes the treatment of needled, nonwoven, rayon fabrics.



   A viscose rayon nonwoven fabric (Avril), 226.8g / yard, needled to form a sort of 45.4g / yard polypropylene muslin, calendered and Palmer, had a tendency to swelling and increased caliber during. wet processing. This disadvantage can be overcome by the use of fabrics consisting of a combination of polypropylene fibers and viscose rayon. Thanks to the thermoplasticity of polypropylene, this combination of

 <Desc / Clms Page number 20>

 fibers and pass it through a Palmer, in order to reduce its initial size and prevent swelling, as well as increase in size during the preliminary soaking. But these tissues still swell and increase in size when wet. In addition, the inclusion of polypropylene fibers is expensive.



  EXAMPLE 10
The following fabrics were used: (a) 226.8g / yard viscose rayon (Avril) needled with 45.4g / yard polypropylene; (b) 226.8g / yard 60% Polypropylene and 226.8g / Yard 40% Viscose Rayon (Avril) fabric, needle punched, in 45.4g / yard polypropylene scrim; (c) 60% polypropylene 93.5g / yard and 40% rayon viscose (Avril) fabric needled with 3.3g / yard cotton.



   Fabrics (a), (b) and (c) are all needled, calendered, and Palmered.



   The aqueous mixture applied to the tissues contains:
 EMI20.1
 
<tb> <SEP> methyl <SEP> carbamate <SEP> 1%
<tb>
<tb> formaldehyde <SEP> 4%
<tb>
<tb> <SEP> magnesium <SEP> <SEP> 0.83% chloride
<tb>
<tb> <SEP> formic acid <SEP> 0.83%
<tb>
 adduct of ethylene oxide and nonyl phenol, as wetting agent 0.2%
This mixture, called Composition A, is applied at 49 ° C., using a laboratory padding device. After drying the fabrics (a) and (b) in a continuous oven at 121 C, and the fabric (c) at 104.4 C, the fabrics are rolled up and held in an oven at

 <Desc / Clms Page number 21>

 convection at 104.4 C to simulate the wrapping conditions of fabrics during their industrial production.

   Thermocouples, incorporated into the fabric rolls, indicate the following temperatures inside the rolls:
 EMI21.1
 
<tb> Placed <SEP> in <SEP> the <SEP> oven <SEP> 51.7 C
<tb>
<tb> After <SEP> 25 <SEP> minutes <SEP> 76.7
<tb>
<tb> After <SEP> 45 <SEP> minutes <SEP> 85.0
<tb>
<tb> After <SEP> 1 <SEP> hour <SEP> 1/2 <SEP> 93.3
<tb>
   The tissue gauges, before and after treatment, are measured using a hand-held, spring-type Starrett 1010 micrometer, with a foot and a 6.35 mm anvil. The sizes, after wetting in water, are also measured.
 EMI21.2
 



  Formalde '' {of% Caliber (sec) Caliber (after-
 EMI21.3
 
<tb> fixed <SEP> mm <SEP> saturation <SEP> in
<tb>
<tb> water) <SEP> mm
<tb>
<tb> Fabric <SEP> (a) <SEP> not <SEP> treated <SEP> 0 <SEP> 1.016 <SEP> 1.725
<tb>
<tb> "<SEP>" <SEP> processed <SEP> 0.66 <SEP> 1.143 <SEP> 1.500
<tb>
<tb> Fabric <SEP> (b) <SEP> not <SEP> treated <SEP> 0 <SEP> 1.016 <SEP> 1.041
<tb>
<tb> "<SEP>" <SEP> processed <SEP> 0.51 <SEP> 0.862 <SEP> 0.786
<tb>
<tb> "<SEP> (c) <SEP> no <SEP> traizé <SEP> 0 <SEP> 0.560 <SEP> 0.737
<tb>
<tb> "<SEP>" <SEP> processed <SEP> 0.56 <SEP> 0.584 <SEP> 0.635
<tb>
 
For each pair of measurements the treated sample has a much lower wet caliber than the untreated sample * The treatment also increases compression and restriction of the tissue (b), designed for restricted swelling .

   In this example and in the following examples, the percentage of fixed formaldehyde is calculated relative to the total weight of the fabric,

 <Desc / Clms Page number 22>

 EXAMPLE 11,
The fabric used is a 226.8g / yard viscose rayon, needled into a 45.4g / yard polypropylene scrim; it is calendered and passed to the Palmer.



   Composition A of Example 10 is padded on only part of the fabric. A portion of this treated part is subjected to vacuum extraction, between the upper roll of the scarf and the roll of fabric; other portion of the same part is not subjected to vacuum. The fabric is dried continuously in an oven at 121 C. From the indications of a radiation pyrometer (Infra- scope), it can be seen that the temperature of the treated fabric is 105 C for the part extracted under vacuum and of 103.3 C for the part not extracted.



  The results of the swelling tests carried out on these tissues give:
 EMI22.1
 
<tb> .Formaldehyde <SEP>% <SEP> Rating <SEP> Rating <SEP> after <SEP> Rating <SEP> after
<tb>
<tb> (sec) <SEP> saturation <SEP> by <SEP> saturation <SEP> by
<tb>
<tb> fixed <SEP> mm <SEP> water <SEP> mm <SEP> NaOH <SEP> at <SEP> 10%
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> No <SEP> processed <SEP> 0 <SEP> 0.990 <SEP> 1.270 <SEP> 1.778
<tb>
<tb>
<tb>
<tb> Treat <SEP> 0.51 <SEP> 1.220 <SEP> 1.095--
<tb>
<tb>
<tb>
<tb> After <SEP> extrac-
<tb>
<tb>
<tb>
<tb> tion <SEP> under <SEP> empty <SEP> 0.68 <SEP> 1.245 <SEP> 1.220 <SEP> 1.524
<tb>
 
The slight decrease in size in the two treated tissues is only apparent because the results represent the means of 10 measurements whose variations are approximately # 0.051 mm.



  EXAMPLE 12
The determinations are made on the following fabrics (a) A 26.8g / yard viscose rayon needle punched with poly-

 <Desc / Clms Page number 23>

 45.4g / yard propylene, calendered and Palmered (b) A 226.8g / yard fabric of 60% viscose rayon, 40% polypropylene, needled into 45.4g / yard polypropylene scrim ; (c) A 226.8g / yard fabric of 60% viscose rayon and 40% polypropylene, needled with 45.4g / yard polypropylene, calendered and Palmered.



   The treatment solutions are: Composition A of Example 10; Composition B, similar to Composition A, except that it contains 8% formaldehyde; Composition C, similar to Composition A, but containing 2% methyl carbamate and 8% formaldehyde.



   All of these compositions were applied with a laboratory padding device at room temperature and extracted in vacuo.



  The fabrics are dried continuously at 126.7 C. The surface temperatures reach: 111.1 C for the fabric treated with composition A, 101.1 C "" "" B,
98.9 C He He '' "C.



  These temperature differences influence the amount of formaldehyde fixed.



    After drying, the fabrics are treated with sodium bisulfite solution to remove the formaldehyde odor and reincorporated from the catalyst by treatment with an aqueous mixture containing 0.83% MgCl2 and formic acid, respectively. The tissues are

 <Desc / Clms Page number 24>

 then made dry to the touch by passing through an oven at 149 C.



  They are then calendered at 121 ° C. on a 2-cylinder calender, then passed through the Palmer, in 2 passes at 127 ° C. on a drum of a 2-drum compression shrinkage machine.



  As in Examples 10 and 11, the size is measured in the dry state, after saturation with water and after saturation with an NaOH solution. The measurements are noted before calendering, after calendering and after calendering and passage through the Palmer. The results of these tests as well as of the formaldehyde analyzes are given in the following table.
 EMI24.1
 
<tb>



  Fabric <SEP> Composition <SEP>, Formal- <SEP> Caliber <SEP> Caliber <SEP> after <SEP> Caliber <SEP> after
<tb>
<tb>
<tb> hyde <SEP>% <SEP> (sec) <SEP> saturation <SEP> to <SEP> saturation <SEP> a-
<tb>
<tb>
<tb> fixed <SEP> mm <SEP> water <SEP> - <SEP> mm <SEP> with <SEP> NaOH <SEP> at <SEP> 20%
<tb>
<tb>
<tb>
<tb> mm
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> No <SEP> processed <SEP> 0 <SEP> 1.070 <SEP> 1.375 <SEP> 1.778
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> A <SEP> before <SEP> calan-
<tb>
<tb>
<tb>
<tb> drage <SEP> 0.72 <SEP> 1.194 <SEP> 1.220 <SEP> 1.475
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> A <SEP> calendered <SEP> - <SEP> 0.916 <SEP> 1.195 <SEP> 1.375
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> A <SEP> calendered
<tb>
<tb>
<tb>
<tb> and <SEP> passed <SEP> to
<tb>
<tb>
<tb>
<tb> Palmer <SEP> 0.77.

   <SEP> 0.916 <SEP> 1.145 <SEP> 1.375
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> B <SEP> Before <SEP> ca-
<tb>
<tb>
<tb>
<tb> landrage <SEP> 0.60 <SEP>, 1.143 <SEP> 1.195 <SEP> 1.475
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> B <SEP> calendered <SEP> - <SEP> 0.916 <SEP> 1.195 <SEP> 1.350
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> 8 <SEP> calendered
<tb>
<tb>
<tb> and <SEP> passed <SEP> to
<tb>
<tb>
<tb>
<tb>
<tb> Palmer <SEP> 0.47 <SEP> 0.815 <SEP> 1.120 <SEP> 1.425
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> C <SEP> before <SEP> ca-
<tb>
<tb>
<tb>
<tb> landrage <SEP> 0.56 <SEP> 1.145 <SEP> 1.195 <SEP> 1.450
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (a) <SEP> C <SEP> grille <SEP> - <SEP> 1.043 <SEP> 1.195 <SEP> 1.375
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>. (a)

   <SEP> C <SEP> calendered
<tb>
<tb>
<tb>
<tb> and <SEP> passed <SEP> to
<tb>
<tb>
<tb>
<tb> Palmer <SEP> 0.45 <SEP> 0.867 <SEP> 1.195 <SEP> 1.580
<tb>
<tb>
<tb>
<tb>
 

 <Desc / Clms Page number 25>

 
 EMI25.1
 
<tb> (b) <SEP> No <SEP> processed <SEP> 0 <SEP> 1.580 <SEP> 1.475 <SEP> 1.730
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (b) <SEP> A <SEP> before <SEP> ca-
<tb>
<tb>
<tb>
<tb> landrage <SEP> 0.44 <SEP> 1,350 <SEP> 1,400 <SEP> 1,375
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (b) <SEP> A <SEP> calendered <SEP> - <SEP> 1.016 <SEP> 1.095 <SEP> 1.145 <SEP>. <SEP>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>



  (b) <SEP> A <SEP> calendered
<tb>
<tb>
<tb>
<tb> and <SEP> passed <SEP> to
<tb>
<tb>
<tb> Palmer <SEP> 0.46 <SEP> 1.016 <SEP> 1.016 <SEP> 1.095
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (c) <SEP> No <SEP> processed <SEP> 0 <SEP> 0.712 <SEP> 0.814 <SEP> 1.070
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (c) <SEP> A <SEP> before <SEP> ca-
<tb>
<tb>
<tb>
<tb> landrage <SEP> 0.53 <SEP> 0.762 <SEP> 0.762 <SEP>, <SEP> 0.916
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (c) <SEP> A <SEP> calendered <SEP> - <SEP> 0.712 <SEP> 0.740 <SEP> 0.867
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> (c) <SEP> A <SEP> calendered
<tb>
<tb>
<tb> and <SEP> passed <SEP> to
<tb>
<tb>
<tb>
<tb> Palmer <SEP> 0.46 <SEP> .0.635 <SEP> 0.662 <SEP> 0.891
<tb>
 
It can be seen that the tendency to swelling of all the tissues of this example is reduced.

   The dry gauge of the untreated fabric (b) is artificially high because this fabric is in a flaky state; if it were normally compressed, like other tissues, its caliber would be considerably less than 1.475.



   For the decrease in swelling of the tissues to be significant, they should contain cellulosic fibers, for example 10% or more, generally at least 20%.



   Examples 13 and 14 show the speed at which it is possible to process tissue. They also show the speed of the reaction, when conditions are favorable.



   EXAMPLE 13
3 light white fabrics, containing 65% polyester fibers and 35% cotton fibers, are treated with an aqueous mixture containing 1% methyl carbamate, 6% formaldehyde, 0.83% chlorine.

 <Desc / Clms Page number 26>

 magnesium ride, 0.83% formic acid, 0.5% acrylic polymer, composed of ethyl acrylate, ethyl methacrylate, acrylic acid and acrylamide (sold under the trade name of "Rhoplèx E-32), 0.25% polyvinyl alcohol and 0.2% of, - ethylene nonyl phenol oxide condensate (as a wetting agent), The treatment is followed by drying .



  The 3 fabrics treated are: a) A fabric at 125 x 72, of 7.5m / Kg (count of threads and weight) b) A batiste at 96 x 84, of 8.6m / Kg (") c) A batiste at 94 x 80, 8.7m / Kg (") The polyester of fabrics (a) and (c) is the polyester sold under the trade name of" Dacron ", and that of fabric (b) is the polyester sold under the trade name of "Kodel".



  The water uptake of these fabrics, after padding in the aqueous mixture, is of the order of 35 to 40%.



  It is dried on a dryer ream, the air temperature of which is set at 166 ° C. The treatment speed is 110.6 m / minute and the fabric stays in the dryer for 14 seconds.



  Tissue temperatures are between 1180 and 124 C, read with the infrascope.



  After drying, padding through a solution of sodium bisulfite, to remove unreacted formaldehyde and any undesirable odor (according to American Patent No. 2,870,041 filed June 2, 1958), washed and dried, a softener based on fatty acid; then, after drying, the fabric is passed through a compression shrinkage machine.



  The tissues, thus treated, fixed the following amounts of

 <Desc / Clms Page number 27>

 formaldehyde, which remains practically constant after numerous washes.



   Formaldehyde% found (1)
 EMI27.1
 
<tb> Sample <SEP> Like <SEP> than <SEP> After <SEP> 5 <SEP> After <SEP> 5 <SEP> washes <SEP> After <SEP> 5 <SEP> washes
<tb>
<tb>
<tb>
<tb> treated <SEP> <SEP> washes at <SEP> Sanforize <SEP> industrial
<tb>
<tb>
<tb>
<tb>
<tb> (2) <SEP> - <SEP> (3 <SEP> (4) <SEP> (5)
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> a <SEP> 0.62 <SEP> 0.56 <SEP> 0.50 <SEP> 0.53
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> b <SEP> 0.59 <SEP> 0.56 <SEP> 0.56 <SEP> 0.52
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb>
<tb> c <SEP> 0.62 <SEP> 0.61 <SEP> 0.62 <SEP> 0.61
<tb>
 (1) based on the total weight of fabric; (2) degreased for 1 hour at the boil with 1% sodium carbonate; (3) test according to the American standard AATCC Tentative Test Method
88 - 1964 T.



  (4) Wash for one hour from near boiling point.



  (5) Washing at 71 C, bleaching with chlorine, degreasing with silico 'zinc fluoride, cycle of 37 minutes.



   The fabrics also exhibit excellent ready-to-wear fabric properties immediately after washing, they hold firm after many washes, and they stay white where untreated fabrics lose their whiteness. In industrial washing, colored garments made from untreated fabrics stain strongly, while treated fabrics hardly stain.



  EXAMPLE 14
The 3 fabrics of Example 13 are passed through a mixture containing 1% methyl carbamate, 4% formaldehyde, 0.83% magnesium chloride, 0.83% formic acid, 0, 5% Rhoplex E-32 acrylic polymer, 0.7% acid-based softener

 <Desc / Clms Page number 28>

 fatty and 0.2% of the condensate propylene oxide-nonyl phenol as - wetting agent.



   The fabrics are dried as in Example 13, except that the speed is 82.3 m / minute and the temperature cure of the fabric of the order of 121 to 127 C, read with a pyrometer on the infrared. -red After the treatment, the fabrics are subjected to the same process as in Example 13 with the bisulfite and the softener, except that the mixture containing the softener also contains 1.4% MgCl2 and
1.4% H COOH.



   The fabrics are hardly dried after this last treatment, to avoid too much loss of the acid.



   The properties of these fabrics are the same as those of the products treated according to Example 13; the more we see the conservation, a marked fold, after pressing and washing. This is how bands pleated by pressing for 15 seconds at a steam pressure of 7 Kg / cm2 in a press known as FORSE, retain a clean and smooth fold after numerous washes.



   This example shows that it is possible to impart lasting shape retention to the fabrics treated according to the invention.



   EXAMPLE 15
A heavy cotton twill (290g / m2), previously mercerized and dyed, passes through an aqueous mixture containing:
1.0% methyl carbamate
4.0% formaldehyde
0.83% MgCl2 C, 83% H COOH
1.0% acrylic polymer (Rhoplex E-32) 0.5% polyvinyl alcohol

 <Desc / Clms Page number 29>

   0.2% of the ethylene oxide-nonyl phenol condensate (wetting agent).



   The drying takes place on a dryer ream whose air temperature is set at 166 C; that of the fabric, measured with an infrared pyrometer, is 110 ° C. The residence time in the oven is 21 sec. counts.



   The tissue then passes through a buffered aqueous catalyst mixture, containing: 0.83% MgCl2
0.83% H COOH 0.50% Na2S205 (sodium meta bisulfite)
2.5% emulsified tall oil, softening.



   Dry in a dryer with an air temperature of 121 C, that of the fabric being 88 C.



   Pleated strips of the fabric are created by steam pressing, for 15 seconds, under a pressure of 7 Kg / cm2, then heated in a convection oven at 163 C for 6 minutes.



   After much damage the fabric retains its folds and its appearance is excellent.



   Similar results are obtained when the pressed fabric is heated in a convection oven at 135 ° C for 6 minutes.



   As indicated above, it is advisable, to promote the preservation of the folds, to add catalyst to compensate for the loss thereof during the initial heating, intended to dry the fabric treated with formaldehyde. The fold retention properties are then imparted after the fabric is initially heated.



   It is also possible to use mixtures of carbamates, such as for example eutectic mixture containing 52% of carbamate

 <Desc / Clms Page number 30>

 ethyl and 48% methyl carbamate.



   Among the aryl carbamates suitable for the invention, mention may be made of phenyl, o-tolyl, p-tolyl, m-tolyl, p-butylphenyl, alpha-naphthyl, beta-naphthyl, 2,4-xylyl carbamates. .



   Of course, the invention is in no way limited to the examples described; it is capable of numerous variants accessible to those skilled in the art, depending on the applications envisaged, without departing for this from the spirit of the invention.
 EMI30.1


 

Claims (1)

ABSTRACT The object of the invention is, 1. Process for fixing an aldehyde on a cellulosic material or starch, which consists of a treatment with an aqueous mixture containing the aldehyde and a carbamic ester, optionally substituted on nitrogen, the aldehyde. or / and the carbamic ester possibly being partially or totally in the form of a condensation product of these two reactants, the treatment comprising heating to a temperature sufficient to fix the aldehyde on said material, but insufficient to fix nitrogen in appreciable quantity. The method can also have one or more characteristics according to points (2) to (@) below. 2. Aldehyde is formaldehyde. 3. The carbamic ester is an alkyl carbamate. 4. The carbamic ester is an aryl carbamate. 5. The next ester (3) or (4) has one or two hydrocarbon substitutions on nitrogen. 6. The aqueous mixture contains an acid catalyst, possibly latent. 7. The aqueous mixture contains a basic catalyst. <Desc / Clms Page number 32> 8. The carbamic ester is a lower alkyl carbamate, especially methyl or ethyl. 9. The proportion of alkyl carbamate is 0.1 to 5% of the aqueous mixture. 10. The formaldehyde / carbamate molar ratio, in the aqueous mixture, is at least 3, and generally between 3 and 60 or between 3.5 and 100. 11. The heating temperature is about 80 to 150 C. 12. The treated cellulosic material is cotton or regenerated cellulose such as viscose rayon. 13. In the case of cotton, the formaldehyde fixation rate is 0.25 to 1.25% by weight. 14. The degree of binding of formaldehyde to cellulose is 0.5 to 2.5% by weight for regenerated cellulose. 15. The aqueous mixture is practically neutral. 16. The treatment is applied to reduce the swelling tendency of the cellulosic fibers. 17. The treated cellulose fibers contain a significant content of regenerated cellulose fibers. <Desc / Clms Page number 33> 18. The treated cellulosic fibers contain at least 35% viscose rayon fibers. 19. The treatment is applied in order to impart to the fibers the property of retaining the shape and the fold. 20. In the treatment according to (19), an additional amount of catalyst is added to the treated fabric which is then dried, pressed and heated. 21. As a new industrial product, a textile which has undergone the treatment according to one or more points (1) to (20).