US2668127A

US2668127A - Method of moth proofing woolen goods

Info

Publication number: US2668127A
Application number: US244106A
Authority: US
Inventors: Eriksson Erik Birger
Original assignee: Individual
Current assignee: Individual
Priority date: 1950-09-01
Filing date: 1951-08-28
Publication date: 1954-02-02
Anticipated expiration: 1971-02-02

Description

standardized testing conditions considerably lower than the amount of 0.8 mg. per larvae which is indicated as an acceptable limit for the attack of moth larvae on an entirely antimoth proofed woollen fabric.

In spite of deficient knowledge about the nature of the bonds between the silico fluorides and the wool it appears that it is not a question of genuine valence combinations, but a question of coordinative binding forces between the silico iluoride complex and the wool substance. These binding forces will be fully developed only when the amino groups of the wool substance are entirely free from acid residues, and consequently it is obvious that they will in the first place act between these amino groups and the Silico fluorides. A blocking of the amino groups by anions from dye-stuffs to a normal, i. e. to a relatively limited, extent, does not seem to disturb the binding forces, but such a disturbance` appears only when blocking occurs by acid anions which cause a decrease of the pl-l value in the surface layer of the fibres.

The susceptibility of the nbre material to acid is very great. Thus, experiments have shown that woollen material which has been subjected to treatment in an acid bath (dye bath), then carefully rinsed in water and further treated in a buffered solution having a pH value of 6, could not nx the silico uorides in a subsequent treatment in a solution of silico iluoride having a normal pH value of 4.0 to 4.5, so that a washing fastness was obtained. Thus, in all such cases where acid residues are present in the wool a real neutralization with a small excess of akali must be carried out to obtain a xation resistant to washing. If the treatment with silico fluoride is carried out on a non-neutralized material a normal absorption of silico fluoride in the wool (0A-0.5% iiuorine) will generally be obtained, but the nxation will not be genuine and most of the fluorine will be removed upon ordinary washing. Neutralization with ammonium is to be preferred as it will then be easier to remove the excess of alkali by rinsing than if soda is used.

y Besides being resistant to alkaline washing the bond between a neutral wool and silico fluoride is to a certain extent intact also against the action of a boiling acid bath. If the concentration of the acid is increased to such an extent that the pH value falls below 3.0, the bond will gradually break up, so that the fluorine is removed. This means that in such cases where it is a question of dyeing wool free from acid in a dye bath not containing great quantities of acid (acid dyeing or chrom dyeing) thetreatment with silico fluoride may take place just before the dyeing.

It has also been proved that a neutral wool can be treated in a Silico fluoride bath to which considerable amounts of acid have been added and a resistant fixation of the silico fluoride in they wool may be obtained. In this case it appears that the silico fluoride is bound to the wool so quickly that a reaction betweenthe acid and the amino groups of the wool will not have time to occur to any noticeable degree until the silico fluorides are already xed. Thus, when it is the question of dyeing wool free from acid in a dye bath containing small quantities of acid (1.0- 2.0% of the weight of the wool) it is in practice possible to carry out the treatment with silico iiuoride at the same time as the dyeing. When on the other hand the dyeing bath contains greater amounts of acid (neulan-dyeing) the treatment with silico fluoride can be carried out complete fixation will take place.

only lafter the dyeing and must then be preceded by a careful neutralization. In this connection it will be observed that a so-called carbonization after a treatment with silico fluoride entirely destroys the anti-moth protecting effect in that the silico fluoride is destroyed and decomposed by the concentrated sulphuric acid which in this process acts on the wool during the drying. After neutralization of the acid woollen material it is, however, possible to treat the material successfully with silico fluoride in a normal way.

It has furthermore been found that the fixation effect is further improved if the wool after the treatment with silico iiuoride is treated in a f. bath containing ordinary soaps of fatty acids.

Certainly, the fixation effect obtained by the method described above is sunicient to prevent the silico fluorides from being removed by a simple rinsing Yin water, and as soon as the cloth is washed in a soap solution the above-mentioned If, however, the washings are instead carried out by means of synthetic washing agents it has been shown that the silico uorides are extracted to a large extent, and it may therefore be necessary to carry out a complete fixation of the silico fluoride in the factory by a simple treatment in soap solution. After such treatment the following washings in synthetic washing agents will cause no noticeable .f extraction of fluoride.

Regarding the nature of the fixation achieved in this way nothing can be said with certainty but conditions are likely to be the following. Only a part of the amino groups of the wool are responsible for the genuine fixation of the silico nuorides. These amino groups are evidently very easily blocked by acids which is why the wool must be neutralized before the Silico uoride treatment, which should be carried out at a pH value about corresponding to the natur-al pH value of the acid ammonium silico fluoride solutions. If these amino groups are free they will in the first place form salts with the silico fiuorides. In the subsequent treatment with soap small amounts of fatty acids are likely to be precipitated as the wool is acid. On account of special relations between adjacent p olar groups the precipitated fatty acids will evidently enter into some complex formation between the wool and the silico iiuorides. The cloth thus impregnated with silico iiuoride and treated with soap may then be subjected to repeated washings in alkaline baths as well as in baths containing diiferent kinds of synthetic washing agents without the silico fluoride being removed but to the limit (about 0.20% nuorine based on the weight of the wool) determined by the active groups in the f wool.

Example 1 A strip of white woollen fabric weighing 30 g. was dyed by boiling for 2 hours with 3% neulandyestui (neulan red GRE) in a dye bath containing 8% sulphuric acid and 10% crystallized sodium sulphate, calculated on the weight of the fabric. The fabric was rinsed in flowing water during 30 min. and then treated for 10 min. at room temperature in a solution containing 0.05-normal ammonia at a ratio of 1:25 between material and liquid. The material was then rinsed for 5 min. in flowing water and treated for 20 min. at a temperature of about 25 C. in a solution containing Y3% ammonium silico uoride, calculated on the weight of the material at a bath ratio of 1:25. Finally rinsing.

l in flowing water` for 1i) min. and drying took place. Y

For determination of the washing fastness `of the impregnation, samples Vof 'the impregnated fabric were washed l, 2 'and 4 times respectively in solution containing 5 fg.. soap per liter. The treatment took plaeeduring naif an'hoiir at a bath `ratio of 1:50 .and a twmerature of 40 C'. after each washing the fabric was rinsed i3 for 2 min. each time :in distilled water at 10 C. l

In. biological with moth larvae aladin analyzing the amount of ilumine in the fabric the 'multe in the following 'tableware obtained:

.A :si-.nip of chromium-dyed and carbonized but not fully neutralized woolen fabric containing 1.2%v sulphmii'c acid was treated for 15 min. at room temperature in a 0.05-normal solution of soda @at sa bath ratio of 12:25. "The :fabric was rinsed in flowing water for l5 .minar-1d treated at 25 C. for 20 Imin. at a bath ratio of 1:25 in a solution containing 3% ammonium Silico uoride, calculated on the weight of the fabric. ."Finally, the fabric was rinsed in owingwater for '10 min.

in biological testing with moth larvae and in analyzing the amount of fluorine the results in the following table were obtained. The washings of the samples were carried out as in Example 1:

. Example 4 20 .g-"White uncrded wodlV dye'dbygboiif Ilng for l hour with 3% Azorhodin 2G in 'a dye bath containing 3% Vsulpl-iuric acid and 10% crystallized sodium sulphate, calculated on the weight of the wool. The wool was then rinsed in 'owing water for 30 min. and treated at room temperature for min. in a solution containing ll.05normal .ammonia at a bath ratio of 1:50. The wool was rinsed for 10 min. in :ilowing water and treated for 1'0 min. ata temperature of about 25 C. in a solution containing 3% ammonium slico iiuoride, .calculated on 4the weight of vthe Wool, at a bath ratio of 1:50. Finally, rinsing in flowing water for 10 min. and drying took place.

In biological testing with moth 'larvae and in analyzing the .amount .of fluorine the results in the .followingy table` wem obtained. The washings of the lsamples ywere carried out .in Ex ample 1 Example '5 .A white woollen fabric was neutralized with ammonia .and rinsed in flowing water. The fab? ric was then impregnated at `a temperature .of .25 C.. and a hath-ratio of 1:25 .01220 min. in an ammonium silice fluoride solution of afaryingom centration. Finally, the fabric was rinsed in ilowing water of room temperature for min. The onsump- Percent results are given in the following table. The Fahne 011m 1g-f Hummel t0 amount vof silico fluoride is given in `percentage larvae the fabric 1 Y.

of .weight of fthe fabric.

`lllmvhasdhed ggg C' as e once Y ontent oiammoniirm silico Washed twice 0.56 0.20 uoriden the bathin Unwashed Washed Washed Washeditimes 0.56 0.20 percent weight Habra once twice 0.25v `0.19l 0.08 Example 3 0.32V `0.21 n.21 0. 39 0. 21 0. 20 A strip of undyed but carbonized and not fully 0.40 0:21- 0.121 neutralized woollen fabric was treated for 15 min. l 143 0-21 0-20 at room temperature in a 0.05-normal ammonia solution at a bath ratio of 1:25. The fabric was then rinsed in flowing water for 15 min. and treated at C. for 20 min. at a bath ratio of 1:25 in a solution containing 3% ammonium silico fluoride, calculated on the weight of the fabric. 3% sulphuric acid, 10% crystallized sodium sulphate and 3% Azorhodin 2G was then added to the ammonium silico iluoride bath, whereupon dyeing took place by increasing the temperature to 100% C. and boiling for 1 hour.

Finally, the fabric was rinsed in owing water for 1A; hour. In biological testing with moth larvae and in analyzing the amount of fluorine the results in the following table were obtained. The washings of the samples were carried out as in Example 1:

The results show in the first place that it is sufdcient to use as small quantity of silico nuoride as 1% of weight of the fabric. It is furthermore evident that the wool is capable of binding about 0.20% iluorine disregarding the concentration of silico uoride in the bath. This is vigorous proof of the theory that a well neutralized wool will to a certain extent strongly bind silico uoride and that the wool shows certain spots at which linkage may take place.

Example 6 Uncolored woolen cloth was treated with 0.05-n ammonia solution for 30 min., whereupon the cloth was rinsed in flowing water for 15 min. and. then treated in a silico fluoride bath. The cloth was then divided into three parts which were further treated as follows:

1. One sample was washed four times (each time for 30 min.) at 40 C. in a solution containlng 5 g./1. soap akes.

2. One sample was washed four times in the same way in a solution containing 2 g./1. lauryl alcohol sulphonate. Y

3. One sample was first treated for 15 min. at

7 40 C. in a solution containing 3 g./l. soap, rinsed and washed four times in a solution containing 2 g./l. lauryl alcohol sulphonate. The results appear in the following table:

Sample Treatment Unwashed 0. 42 1 Washed once in soap solution- 0. 22 Washed twice in soap solution..- 0. 20 Washed four times in soap solutlo 0, 2l) Unwashed (l. 42 Washed once in lauryl alcohol sulphonate. l). 14 2 Washed twice in lauryl alcohol sulphonate 0. l0 Wasled -i times in lauryl alcohol sulpho- 0. 09

na e. v Washed once in soap solution (l. 25 Washed once in lauryl alcohol sulphonatc 0. 22 3 Washed twice in lam-yl alcohol sulplionateA 0. 2l Washed 4 times in lauryl alcohol sulplio- 0. 2i

nate

Test No. 3 proves thatabout 0.20% iiuorine is fixed to the wool by the soap treatment, so that thereafter extraction by washing does not occur.

Example 7 A colored Woollen cloth was neutralized as in Example with ammonia, rinsed in flowing water for l5 min. and treated with silico uoride. The cloth was divided into two parts, one of which was treated at room temperature for 30 min. in a solution containing 5 g./l. soap and then rinsed, While the other one was not subjected to such treatment. Both samples were put in distilied water, which was changed every day. Analysis of the iluorine content in each piece of cloth was made after different periods of extraction in distilled Water. The results appear in the following table:

Percent lluorine Time in water Not treated Treated with soap with soap The table shows that a` good iixation is achieved by the treatment with soap.

I claim:

l. A method of moth proofing woolen goods containing acid residues deposited in said goods during the manufacture thereof, which comprises treating the woolen goods in a Water solution containing an alkaline neutralizing agent in an amount in excess of that required to'neutralize all of said acid residues in the woolen goods. rinsing the Wolen goods in water to remove the neutralized acid residues, immersing the Wool in a water solution containing a Water-soluble silico fluoride in an amount corresponding to at least about l by weight of the goods, and drying the woolen goods, whereby said uoride becomes rmly fixed to the bers of said woolen goods and is resistant to displacement therefrom upon repeated washing. Y

2. A method of moth proofing woolen goods as defined in claim l, further comprising the step of immersing the woolen goods after immersion in the water solution of the Silico iiuoride in a water' solution containing a water-soluble fatty acid soap.

- ERIK BIRGER ERI-KSSON.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,634,790 Minaei July 5, 1927 1,682,975 Meckbach Sept. 4, 1923 1,914,059 White June 13, 1933

Claims

1. A METHOD OF MOTH PROOFING WOOLEN GOODS CONTAINING ACID RESIDUES DEPOSITED IN SAID GOODS DURING THE MANUFACTURE THEREOF, WHICH COMPRISES TREATING THE WOOLEN GOODS IN A WATER SOLUTION CONTAINING AN ALKALINE NEUTRALIZING AGENT IN AN AMOUNT IN EXCESS OF THAT REQUIRED TO NEUTRALIZE ALL OF SAID ACID RESIDUES IN THE WOOLEN GOODS, RINSING THE WOOLEN GOODS IN WATER TO REMOVE THE NEUTRALIZED ACID RESIDUES, IMMERISING THE WOOL IN A WATER SOLUTION CONTAINING A WATER-SOLUBLE SILICO FLUORIDE IN AN AMOUNT CORRESPONDING TO AT LEAST ABOUT 1% BY WEIGHT OF THE GOODS, AND DRYING THE WOOLEN GOODS, WHEREBY SAID FLUORIDE BECOMES FIRMLY FIXED TO THE FIBERS OF SAID WOOLEN GOODS AND IS RESISTANT TO DISPLACEMENT THEREFROM UPON REPEATED WASHING.