IL26987A - Antistatic composition containing humectants and alkoxylated amines - Google Patents

Description

ANTISTATIC COMPOSITION CONTAINING HUMECT ANTS AND ALKOXYLATED AMINES o » J *a.n a'n'tna 'Dan η*οϋο»οα» nanyn / ■ ANTISTATIC COMPOSITION ftNTl ERQCESS This invention relates to an antistatic composition adapted for use on textiles and related materials. More specifically this invention relates to an antistatic composi-tion particularly adapted for use on pile fabrics, especially carpeting and upholstery fabrics, normally backed with polymeric coatings. The invention is also concerned with a process for the preparation of an antistatic composition, and a process for treating textiles with an antistatic composition to reduce electrostatic charge build-up in textiles.

The phenomena whereby charges of static electricity are built up in textiles is an acute problem in textile forming and treating processes, and in the normal use of upholstery and carpeting fabrics. Static charges are transferred to the individuals using the textiles, who may receive an unpleasant "shock" when the charge passes from the individual to the ground.

The prior art compositions designed to alleviate this disadvantage have many defects and generally are not suited for use on carpets. Some of the problems incurred with the use of the prior art antistatic compositions are that in many cases the prior art antistatic compositions adversely affect the ability of textile surfaces to be dyed or otherwise decorated. Likewise the prior art compositions often affect adversely the hand qualities of the textile. In many cases, in order to be effective, the prior art compositions must be applied to the fabric or carpet face. While this is permissive for some applications, in most cases it tends to produce an unsightl surface and said coated areas tend to attract r prior art antistatic coatings on carpets and upholstery is severely restricted.

When two or more dielectric materials are rubbed together an electrostatic charge is generated. Due to the dielectric nature of the materials in question, the static charges are not dispersed. This charge build-up is particularly acute in an environment of low humidity. The conditions for generation of electrostatic charge are met when clothing of individuals is rubbed against upholstery fabrics or heir shoes rub, or scuff against carpets, the conditions being particularly favorable for generation of charges of static electricity under the relatively low humidity conditions that are frequently present indoors during the winter months.

When a charge of static electricity has been built up in an individual he can be subjected to the discomfort of a slight "shock" or "spark", particularly when he touches a metallic object to ground himself. If the generated charges of electricity can be dispersed throughout the dielectrical material, upholstery or carpet, they will not build up in persons in contact therewith. The antistatic compositions of this invention allow charges of the subject type to be evenly dispersed throughout textile and textile-type materials.

As used in accordance with this invention the term "antistatic" pertains to reducing or eliminating the property or ability to generate,, induce or accumulate electrostatic charges.

The primary object of the invention at hand is the preparation of a superior antistatic composition.

The antistatic compositions of the invention have the advantage that they do not attract dirt and are not worn compatible with the latex binders which are used as carpet backing and adhesives.

The antistatic composition of the present invention comprises a combination of i) certain tertiary amines, with a compound or mixture of compounds which function as ii) a humectant and iii) an electrolyte. These active ingredients are preferably prepared in the form of an aqueous solution or dispersion so that they can be applied to the back of the material to be protected in the form of an aqueous solution or dispersion.

As a humectant in the composition of the present invention there may be used various deliquescent salts of metals of the Group I and II of the Periodic Table, particularly of the alkali metal and alkaline earth metals. Specific deliquescent salts which we prefer to employ as humectants, include the alkali metal salts of lower aliphatic carboxylic acids, such as sodium formate, potassium formate, lithium formate, cesium formate, sodium and potassium acetate, potassium butyrate and such Inorganic salts as calcium chlo-ride. There may also be used such organic humectants as . glycerol, urea, ethylene glycol, sorbitol, ethoxylated sorbitol lauric acid esters and mixtures of the same.

Where a deliquescent salt is employed as the humectant it may also function as an. electrolyte. However, where glycerine or other nonionic humectant is employed an electrolyte must be added as well.

In the case of deliquescent salts, such as sodium and potassium formate, which have a relatively low dissociation constant, it is preferable also to incorporate a small amount of a salt of a strong base and strong acid having a deliquescent, such as sodium chloride, sodium sulfate, potassium nitrate which do not function wholly satisfactorily as both humectant and electrolyte, can be employed in combination with a nonionic humectant, such as glycerine or urea, or in combination with a more highly deliquescent salt, such as potassium formate or calcium chloride. Thus, in the composition of the present Invention, the humectant and electrolyte may be either a single compound or a mixture of compounds.

The other essential component of our composition is an alkoxylated amine represented by the following general formula : wherein R represents an aliphatic hydrocarbon radical of from about 8 to about 22 carbon atoms, each R» represents hydrogen or methyl and n represents an average integer of at least 1, preferably 1 to about 30, although higher alkoxylated derivatives, i.e., the products obtained by condensing 1 molar proportion of a primary aliphatic (saturated or unsaturated) amine with up to 50 molar proportions of an alkylene oxide, usually ethylene oxide, may be employed, if desired. Such alkoxylated amines are well known in the art and are prepared by condensing the primary saturated or unsaturated aliphatic amine of from 8 to 22 carbon atoms, with an alkylene oxide, usually ethylene oxide, although propylene oxide and butylene oxide may be employed if desired, until polyglycol groups of the desired chain length are obtained.

The composition of the present invention comprises a mixture of the above components preferably in the following relative proportions in which the parts are by weight. For amounts to about 5 parts of humectant. If the particular humectant employed is also a strong electrolyte, the amount employed as a humectant is sufficient to function as an electrolyte. However, if the particular humectant is not a strong electrolyte, from 0.01 parts to about 0.1 parts of a strong electrolyte is also employed. Both components are preferably prepared in the form of a concentrated aqueous solution or dispersion.

It is within the purview of this invention to add to the composition compatible materials which do not affect the basic and novel characteristics of the composition of this invention. Among such materials are wetting agents of the nonionlc or cationic type. Such wetting agents may be used in amounts of from 0.01 to 0.1 part by weight and are preferably included in the composition when a heavy pile fabric, particularly carpeting, is being treated, as they facilitate the penetration of the antistatic composition into . the textile substrate. It is desirable to add a measured amount of wetting agent as determined by preliminary test, to control the degree of penetration of the composition into the textile substrate - particularly when treating carpet -so that the composition penetrates the backing of carpet and wets the base of the pile fabric, but does not penetrate to the outer tips of the pile. Other materials which can be incorporated in the composition include coloring agents, including dyes and pigments, fillers and similar additives, antioxidants, additional antistatic agents, stabilizers and defoaming agents. There may also be incorporated various volatile water soluble solvents, such as lower alcohols of 1 to carbon atoms or acetone in order to facilitate the Invention is prepared by dissolving the several components alkoxylated amine, combined humectant and electrolyte, or a humectant and an electrolyte, in water, the order of addition being immaterial, and mixing at a temperature from room tem-perature to about 100°C. until a uniform composition is obtained. When a salt of a lower carboxylic acid is employed as the humectant or combined humectant and electrolyte, it may be formed in situ by adding carboxylic acid having from about 1 to about 5 carbon atoms and an alkali metal or alkaline earth metal base, i.e., hydroxide or carbonate, such as sodium, potassium, lithium or cesium hydroxide or carbonate.

After, all the components are added to water and a uniform mix is obtained, the pH of the resulting mixture or solution is so adjusted as to be within the range of pH 4 to neutral (pH 7)* preferably slightly acid, more preferably to a pH within the range of from about 5.6 to about 6.5, with the most preferred pH being about 6. This pH adjustment is preferably effected by adding an aliphatic carboxylic acid having from about 1 to about 5 carbon atoms to the mixture. If the salt of a lower carboxylic acid is employed as humectant and/or electrolyte, it is preferable that the pH adjustment be effected using the same carboxylic acid as the anion present in such salt. It will be appreciated that this pH adjustment by addition of carboxylic acid also results in the formation of a salt of the alkoxylated amine.

The antistatic composition of the present invention is particularly useful for the production of the antistatic textile products described and claimed in our copending application Ser. No. 26981 , filed concurrently with the present application. For the sake of complete disclosure, € diagrammatically in the annexed sheet of drawings.

In the drawing, 2 designates a roll of textile material, such as carpeting or upholstery, preferably of pile construction, to be treated. The web of textile 4 is removed from the roll by drive rollers 14 and passes over coating means 6, here illustrated as a spray head which applies the coating composition to the back of the textile. The web of textile then passes through drying unit 8 illustrated diagrammatically in the drawing as a drying oven, wherein it may be subjected to radiant heat and/or heated atmosphere to effect evaporation of most of the water.

It will be apparent that due to the evaporation of water, the temperature of the surface of the textile will not exceed 212°P. However, a surrounding atmosphere having tem-peratures of from 300 to 400°F. may be employed, subject to the practical limitation that the temperature must not be so high as to promote the decomposition or degradation of either the textile substrate or the antistatic coating composition. When essentially all of the water has been removed by vapori-zation, the web of textile passes through suitable apparatus illustrated in the drawings as coating roll 10 for applying a latex backing to the fabric.

In the case of loosely woven or tuf ed carpet structures, the latex backing is applied in the manner cus-tomary in the art so as to assure uniform coating and good adhesion of the latex to the backing and looped ends of the pile. Care should be exercised, however, in applying the latex backing that it does not penetrate completely so as to encapsulate the antistatic coating. If the antistatic coat-ing or layer is encapsulated, its effectiveness is diminished. r such as Lotol GX 3180, available commercially from the Naugahyde Chemical Division of the U. S. Rubber Company, or Burkote R1732 available from Burkart-Schier of General Aniline & Film Corporation, or compounded carboxylated styrene-butadiene rubber, such as Lotol GX-131 , available from Naugahyde Chemical Division of U. S. Rubber Company, or Burkote A 2223 available from Burkart-Schier of General Aniline & Film Corporation. There may also be used compounded neoprene latexes, such as Lotol GX-1076, available from Naugahyde Chemical Division of U. S. Rubber Company, or Burkote R 2285, available from Burkart-Schier, and latexes of polystyrene, vinylidene chloride, polyacrylates, butadiene-styrene or others.

The antistatic composition can be applied in any coating weight which is capable of effecting the desired antistatic properties. For use on carpets, the broad dry coating weight range is from .01.to 12 oz. per sq. yd., with a more preferred range being .5 to 3 oz. per sq. yd. A most preferred dry coating weight for carpets is 1.7 oz. per sq. yd.

For application on conventional textiles, such as woven fabrics, the broad dry coating weight range is from about .10 to about .0$ based on fabric weight. A more preferred dry coating range for textiles is from about 0.8$ to about 3.0$ based on fabric weight. A most preferred dry coating weight for textiles is 2.0$ based on fabric weight.

The invention will now be illustrated by means of the following specific examples in which the parts are by weight: EXAMPLES 1 to 14 In these Examples, the antistatic composition was stearyl amine which had been ethoxylated with 20 moles of ethylene oxide per mole of amine. The wetting agent was tridecyl alcohol which had been ethoxylated with 6 moles of ethylene oxide per mole of alcohol. The amounts of materials employed in each Example are given in the appropriate column of Table I.

In all cases, the antistatic coating was applied to the back of a tufted carpet having a primary loosely woven jute backing, and the type of fibers employed in the tufted pile are given in Table I, as well as the amount of antistatic composition applied to the back of the carpet.. After applicar-tion of the antistatic, coating the carpet was dried to remove excess moisture. Α· latex coating was then applied over the antistatic coating in such a manner that it did not encapsulate the antistatic coating.

The testing procedure used in these Examples was the Walking Foot Scuff Test. This testing procedure is as follows: A carpet sample 9 feet long and 2 to 3 feet wide is spread on the floor. At one end of the carpet an electrostatic volt meter is positioned on a table. Beginning at the volt meter end of the carpet, the experimenter, wearing shoes having leather soles and heels, walks, shuffling his feet all the while to the opposite end, turns while still on the carpet, and returns to the volt meter end of the carpet where he immediately makes a hand contact with the probe. The electrical charge which is accumulated in the experimenter is transmitted to and registered on the volt meter. In all Examples the testing was conducted at 77°F. + 2°F. and at a constant relative humidity of 35 to k0%.

Form A TABLE Hum e c tan t Parts Example Basic Organic Parts Wetting Parts No. Compound Parts acid Parts amine Agent Electrolyte Parts Water 1 NaOH O acetic 60 20 2 NaCl 2 210 2 NaOH ho acetic 60 20 2 NaCl 2 210 3 KOH 56 formic h6 20 2 NaCl 2 l80 k KOH 5 formic k6 20 2 NaCl 2 180 NaOH 20 formic 23 10 1 KC1 1 150 6 NaOH 20 formic 23 10 1 KCL 1 150 7 KOH 56 acetic 60 20 2 NaCl 2 200 8 KOH 56 acetic 60 20 2 NaCl 2 200 9 KOH 56 acetic 25 2 NaCl 3 500 KOH 56 acetic 7* 25 2 NaCl 3 500 11 KOH 69 formic 56 25 3 NaCl 2.5 12 KOH 69 formic 56 25 3 NaCl 2.5 13 u n t r e t e d control Ik u n t r e t e d control EXAMPLES 15 to 31 In these Examples, the samples treated were Nylon and wool tufted carpet structures. In all cases the antl-static coating was applied to the base of the carpet fibers and primary jute and dried. A latex coating was then applied over the antistatic coating in such a fashion that it did not encapsulate the antistatic coating.

In these Examples, the humectant was formed in situ by the reaction of a basic component with an acidic component. The amine and wetting agent were the same as described in Examples 1 to 12.

The testing procedure used in these Examples was the Stationary Foot Scuff Test. This procedure is as follows: The carpet to be tested is spread on the floor (18" x 18" minimum) and the person testing, wearing shoes having leather soles and heels stands on the carpet with one foot stationary. While holding a volt meter probe in one hand, the experimenter rubs his other foot briskly on the carpet pile, a maximum of 15 strokes or until the meter reaches equilibrium. Any charge generated is transmitted through the person and registered on the volt meter. This testing was conducted at 77°P. + 2°F., and at a constant relative humidity of 35 to 0$.

The composition of the antistatic coating, as well as the test results and other pertinent information for these Examples are given in Table II, Form A TABLE II H u e c t an t Parts PH Example Basic Organic Parts Wetting Parts ad Wo. Compound Parts acid Parts amine Agent Electrolyte Parts Water ac NaOH ho acetic 60 20 2 NaCl 2 210 ac 16 NaOH NaCl 17 OH 56 formic 6 l8o fo 18 KOH 19 NaOH 20 23 10 1 KC1 1 150 NaOH 20 23 10 1 KC1 1 150 21 KOH 56 acetic 60 20 2 NaCl 2 200 ac 22 KOH 23 KOH propionic lh 25 3 500 fo 2k KOH KOH 69 formic 56 25 3 2.5 2^5 26 KOH 69 27 29$ N¾0H 121 acetic 60 20 2 NaCl 2 200 28 formic kS 29 propionic u n t r e at e d control 31 u n t r. e a t e d control EXAMPLES 32 to 46 In these Examples, the samples treated were Nylon and wool tufted carpet structures. In all cases the antistatic coating was applied to the base of the carpet fibers and primary jute back and dried to remove the excess moisture. In these examples the wetting agent utilized was in accordance with the description given in regard to Examples 1 to » A latex coating was applied in such a fashion that it did not encapsulate the antistatic coating.

In these Examples, the humectant was not formed in situ but instead was added directly to the antistatic composition. In Examples 38 - 41 the calcium chloride functioned as both a humectant and electrolyte. The test procedure utilized in Examples 32, 33, 35, 36, 38, 39, 41-44 was Stationary Foot Scuff Test as is described above in regard to Examples 15 to 31. The walking foot scuff Test was used in Examples 34, 37 and 40 as per the description given in regard to Examples 1 to 15. These tests were conducted at 77°F. ± 2°F., and at a constant relative humidity of 35 to 40#.

The composition of the antistatic coating, as well as the test results and other pertinent information for these Examples are given in Table III.

Form B ABLE III Parts PH Example Parts Wetting Parts adjustm.

No. Humectant Parts amine Agent Electrolyte Parts Water acid 32 sorbitol 10 20 1 NaCl 1 70 acetic 5. ester 33 CaCl2 20 20 2 - * 100 3V CaCl2 - * CaClg - * 36 CaClg 30 - # 110 5. 37 CaCl2 - * 38 CaCl2 n - # 39 CaCl2 ho - * 120 ko CaCl2 * hi CaCl2 - * h2 Urea 10 10 1 CaCl2 10 100 formic 6. 3 Urea 30 10<2> 1 NaCl 1 110 5. kk CaCl2 30 10<3) 2 - 100 acetic *5 u n t r e a t e d control k6 u n t r e a t e d control 1) Etnoxylated sorbitol lauric acid ester *) Humectant was electrolyte 2) N-octyl, N-ethyl aorphollnium ethosulfate 3) quaternary diethyl sulfate intodazollne EXAMPLES 47 to 75 In these Examples, the samples treated were conventional woven and nonwoven fabrics. In all cases the antistatic coating was applied to the textile and dried to remove the excess moisture. The amine utilized was in accordance with the description given in accordance with Examples 1 to 15. In these Examples, a wetting agent was not utilized so as to prevent the antistatic coating from completely penetrating the textile.

In these Examples, the humectant was formed in situ by the reaction of a basic component with an acidic component as in Examples 1 - 15. The procedure for these Examples was as follows: The samples were cut and coated with the antistatic coating. In these Examples, the coating weight was based on the weight of the fabric in question. A polymeric backing was then applied to the fabric and dried at a temperature of from about 200 to 325°F. for a period of time of from about 10 to 30 minutes* The dried fabric was then conditioned for at least six hours at a temperature of 70 + 5°F. and 35 to 40$ relative humidity. The coated material was then tested on an Atlab tester, as developed by the Atlas Chemical Co., Wilmington, Del. The test procedure consists essentially of a means of controlled rubbing of a strip of fabric across a pair of static-generating (Teflon) bars and across a stainless steel bar which transfers the friction-generated charge to an electrostatic voltmeter for measurement. This testing was conducted at 77°P»,t 2°F,, and at a constant relative humidity of 3 to 0$.

The composition of the antistatic coating, as well as the test results and other pertinent information for these Form ABLE IV pH Example Basic Carboxylic Amine Parts adju No. Compound Parts acid Parts Parts Electrolyte Parts Water acid ¾7 NaOH ¾0 acetic 60 20 NaCl 2 210 acet hQ NaOH NaCl 9 NaOH NaCl 50 NaOH „ NaCl 51 KOH 56 formic he NaCl 180 form 52 OH » NaCl 53 KOH NaCl KOH NaCl 55 NaOH 20 23 10 KC1 1 150 form 56 NaOH KC1 57 NaOH KC1 58 NaOH « KC1 Form ABLE IV Hum e c taa t PH Example Basic Organic Parts Farts adjustm.

No. Compound Parts acid Parts amine Electrolyte Parts Water acid 59 KOH 56 acetic 60 20 NaCl 2 200 acetic 60 KOH II II It NaCl II It II 61 KOH It It II It NaCl II II it 62 KOH It II II II NaCl II II tl 63 KOH It II 25 NaCl 3 500 formic 6k KOH II II It It NaCl It It II 65 KOH It It tl It NaCl II It II 66 KOH it It It It NaCl II II tl 67 KOH 6 formic 56 II NaCl 25 25 It 8 KOH II II II II NaCl II It 11 9 KOH It II II It NaCl II II It 0 KOH It II II It NaCl II It It 1 29$NHyOH 121 acetic 60 20 NaCl 2 200 formic 2 29#N¾<0H II formic II NaCl II It It 3 It II acetic II NaCl It It 11 * u n t r e a t e d u n t r e a t e d f EXAMPLES 76 to 108 In these Examples, the samples treated were conventional woven and nonwoven fabrics of the type and fibers shown in Table V. In all cases, the antistatic coating was applied to the back of the textile sample and dried to remove excess moisture. A polymeric backing was then applied to the fabric and cured at a temperature of from 200° - 325°F« for from 10 - 30 minutes. The coated material was then tested on an Atlab Tester in the manner described above in connection with Examples 7^ 75. In these Examples, the huraectant was not formed in situ, but instead was added directly to the antistatic composition.

The composition of the antistatic coating as well as test results and other pertinent data for these Examples are given in Table V.

Form A B L E Wetting PH Example Amine Agent (2) Parts adjustm.

No. Humectant Parts Parts Parts Electrolyte Parts Water acid 76 sorbitol 10 20 1 NaCl 1 70 acetic ester (3) ft tt II It 77 NaCl 1 II It 78 •r liIt 1 NaCl 1 1» II 79 «r lt It 1 NaCl 1 If II 80 ft It tt 1 NaCl 1 ft It 81 II It 1 NaCl 1 It II 82 glycerol 20 10 0 CaCl^ tt 8 tt It tt ir 5 tt It 85 r» » tt If ft 5 tr II 86 If tt tt tt » 5 tt tr 87 1» It tt n 5 If It 88 C Cl2 20 20 0 * 0 100 acetic 89 It II tt tt tt 90 It tt It It tt It it- tt II 91 tt II tt * 92 It tt ft * «t ft II II II 93 If * II tt »t 9 II 30 It II * II 110 Form ABLE V Wetting pH Example Amine Agent(2) Farts adjustm.

No. Humectant Parts Parts Farts Electrolyte Parts Water acid 95 CaCl2 30 20 0 * 0 110 acetic 96 * 0 97 „ * 98 * 99 „ * 100 uo * 120 101 „ * 102 „ * 103 * 10k „ * 105 „ * 106 urea 30 10 (1) 1 NaCl 1 110 formic 108 K-Octyl N-ethyl morpholinium ethyl sulfate Condensate of tridecyl alcohol with 6 moles of ethylene oxide Ethoxylated sorbitol lauric acid ester Nylon - unless otherwise specified Humectant was electrolyte

Claims (7)

26987/2

1. An antistatic coating composition con fed acting essentially of an aqueous solution of an ionic or nonionic humectant and an alkoxylated tertiary amine, as well as an electrolyte when the humectant is a nonionic humectant.

2. The antistatic coating claimed in claim 1, wherein the alkoxylated tertiary amine has the formula: R -N £—4· CHR* -CHR* -0)nH J g wherein R represents an aliphatic hydrocarbon radical of from 8 to 22 carbon atoms, R1 represents hydrogen or methyl and n is from 1 to 50.

3. The composition claimed in claims 1 or 2, wherein the humectant is calcium chloride.

4. The composition claimed in claims 1 or 2, wherein the humectant is an alkali metal salt of a lower aliphatic carboxylic acid having from 1 -4 carbon atoms.

5. The composition claimed in claims 1 or 2, where in the humectant is potassium formate.

6. The composition claimed in any one of the preceding claims, containing from 1 to 5 parts by weight of humectant and from 0. 01 to 0. 1 part ;by weight of an electrolyte for each part by weight of alkoxylated tertiary amine. of al oi-ylatod ■ 4>&gtiagy ■ amines 1

7 -3% The composition claimed in Claim 8, having a pH in the range of from 4 to 7. 8 A process for rendering a textile antistatic, which comprises coating at least one surface thereof with an effective amount of the antistatic coating composition claimed in any one of the preceding claims. 9 -4Θ-. A process for the preparation of the antistatic coating composition claimed in any one of Claims 1 to 8, which comprises the steps of adding substantially equimolar amounts of an alkali metal base and an aliphatic carboxylic acid having from 1 to 4 carbon atoms to water to produce thereby the humectant in situ, adding thereto the alkoxylated tertiary amine, mixing to obtain a uniform composition, and adding to the mixture a lower aliphatic carboxylic acid having from 1 - 4 carbon atoms in an amount to adjust the pH of said mixture within the range of from 4 to 7. 10 11. The antistatic coating composition claimed in any one of Claims 1 to 8, substantially as herein described with reference to the Examples. 11 -Hh, The process of rendering a textile antistatic as claimed in Claim 9, substantially as herein described with reference to the Examples. 12 ÷3- The process for the preparation of the antistatic coating composition as claimed in Claim 10, substantially as herein described with reference to the Examples. DATED the 30th November, 1966 S. HOROWITZ & CO. Agents for AppliciSitts