JPH05247842A - Antistatic, antifungal fiber - Google Patents

Abstract

PURPOSE: To obtain electroconductive and antifungal textile fibers by soaking treatment of textile fibers in a copper ion-contg. solution followed by an iodide- contg. solution. CONSTITUTION: The electroconductive and antifungal textile fibers are obtained by soaking textile fibers pref. acrylic or modacrylic ones in a solution which is prepared by adding a reducing agent to a solution containing copper ion (cupric ion) to convert the cupric ion to cuprous ion, to effect adsorption of the cuprous ion to the fibers, and then by soaking the resultant textile fibers in a solution containing an iodide or iodate ion to effect adsorption of copper iodide to the fibers. The textile fibers thus obtained are useful in producing VDT screens (video display terminal devices), socks, or the like.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to conductive fibers and methods of making conductive fibers and has particular application to conductive fibers that also exhibit antimicrobial properties.

[0002]

BACKGROUND OF THE INVENTION Video Display Terminal (VDT)
The main health problems associated with can be traced to the emission of electromagnetic radiation, static electricity and airborne bacteria. Any of the above phenomena can cause serious health problems, especially for VDT operators over long exposure periods.

The problems of EMR and electrostatic discharge as well as other problems have been addressed by VD to reduce or eliminate harmful radiation spread.
Reduced or eliminated by the development of an electrically conductive screen mounted on the T viewing screen. Some of these screens and their methods of manufacture are described in US Pat. No. 4,364,739,
4,410,593, 4,468,702, 4,661,3
76, 4,760,456 and 4,819,085.

One of the problems not previously considered is V
Transmission of airborne bacteria from the DT screen to the operator. This problem is of major concern when individual VDTs are used by some users over the course of a day. One operator infected with a particular airborne virus transmits the virus to some other operators using the same terminal device,
It can produce predictable results.

Also, the growth of bacteria in cloth made from certain fibers can damage the fibers due to the growth of moss. Fabric manufacturers currently use quaternary ammonium salts to prevent bacterial growth, but these compounds are water soluble and the protection afforded is actually only temporary.

[0006]

SUMMARY OF THE INVENTION The fibers of the present invention are treated in such a way as to provide the VDT screen with both antistatic and antimicrobial properties. Plain fibers, usually acrylic or modacrylic monofilament fibers, are treated in a bath containing an aqueous solution of copper dioxide ions and a reducing agent capable of converting them to monovalent ions.

The bath also contains an iodine-containing compound that can readily bind monovalent copper ions to form copper (I) iodide, (CuI). CuI is adsorbed on the fiber, giving it both antistatic properties and antibacterial properties due to iodide ions. Two
Two separate baths can also be used to treat the fibers. Fibers produced according to the present invention typically have socks with the following properties:
Used in antistatic and antibacterial cloths used in the manufacture of cloths and textiles.

Accordingly, it is an object of the present invention to provide a method of treating fibers to impart both antistatic and antibacterial properties to the fibers. Another object is to provide a method of previously treating a non-conductive cloth with a solution of copper and iodine. Another object is to provide fibers which can be woven into a framed screen and have the above properties.

Other objects will become apparent upon reading the description below.

[0010]

DESCRIPTION OF PREFERRED EMBODIMENTS The preferred embodiments and methods described are not intended to be exhaustive or to limit the invention to the precise form or steps disclosed. They are chosen and described to explain their principles and their application and practical use so that those skilled in the art can understand their teachings.

In a preferred embodiment, the fibers used are preferably from the acrylic or modacrylic series,
However, other types of cloth could be used. Initially, the fabric fibers have an electrical resistance near 10 ¹³ ohms and are electrically non-conductive. Untreated fibers, when woven into a screen and placed in front of the VDT, cure some of the strain problems inherent in end devices, but do not substantially aid in static and EMR divergence and diffusion of airborne bacterial streams. This type of screen is disclosed in U.S. Pat. No. 4,8, issued April 4, 1989.
No. 19,085, which is referenced.

In order to give the screen electrical conductivity,
The fibers are immersed in a bath containing a solution of aqueous metal ions. In a preferred method, monovalent copper ions reduced from divalent ions are used due to their ability to be readily adsorbed on the fiber. A solution of divalent copper ions, usually CuCl ₂ , CuSO ₄ or Cu (NO ₃ ) _{2 and} the following copper metal, sodium formate, ferrous sulfate, sodium bisulfite, sodium dithionite (Na ₂ S ₂ O ₄ ), Sodium hypophosphite, sodium vanadate, hydroxylamine sulphate, furfural, glucose and hydroxylamine. Other known reducing agents can be substituted or added if desired.
The teachings of this type of bath dipping method are best described in detail in U.S. Pat. Nos. 4,336,028 and 4,410,593. By following these teachings, the fibers are rendered sufficiently conductive to dissipate a significant portion of the static electricity and EMR emanating from the VDT.

An additional component, an iodine-containing compound, is used in the method of the present invention. The method may include a two bath treatment in which the fibers are first dipped in a solution of copper ions and then after washing the copper impregnated fibers are dipped in an iodine solution.
Alternatively, a one-bath treatment of copper ions and iodine ions can be used. A significant amount of sodium thiosulfate (Na ₂ S
₂ O ₃ ) can be used in a one-bath or two-bath system. Sulfur ions are compatible with iodine ions. The fibers are first impregnated with copper ions and then the negative ions are adsorbed. S ^-2 ,
Varying the concentrations of I ⁻ and Cu ⁺² gives different results of color, conductivity and bacterial inhibition.

The bath may also optionally include an acid or salt that adjusts the pH of the bath. Suitable acids and salts for this purpose are inorganic acids such as H ₂ SO ₄ or organic acids such as citric acid. The temperature of the treatment bath is preferably in the range of 50 to 120 ° C. At high processing temperatures, the strength of the fiber is likely to deteriorate, but the processing time will be shortened. At low temperatures the processing time will be undesirably long.

After the fiber has been treated with the bath (s), it is dried normally and then can be used to make cloth for socks or other articles, or can be woven into a screen. Some screens are described in US Pat. No. 4,760,456 (July 1988).
Issued on May 26) and No. 4,819,085 (April 1989)
Issued on May 5th) and explained. Iodine-containing compounds are preferably potassium iodide, potassium iodate, sodium iodide, sodium iodate and I ^−.
Or one of many other metal iodides and iodates capable of liberating IO ₃ ⁻ ions, but others can probably be used with similar results. Various results in conductivity and bacterial inhibition are obtained by varying the concentration of copper, sulfur and iodide ions in the solution, so the invention is not limited to a particular concentration.

The following examples are illustrative of the methods used to form antistatic and antimicrobial fibers of the present invention. Example 1 A small piece of acrylic cloth measuring 2.5 cm × 1.5 cm was thoroughly washed with CuCl 2.
_It was immersed in a hot bath containing ₂ and NaHSO ₃ . The amount of each compound in the solution compared to the fabric weight was 30% CuCl ₂ and 15% NaHS
O ₃ , and the cloth to solution weight ratio was 1:40. The bath containing the cloth was gradually heated to 90 ° C. and the cloth was immersed for 60 minutes.
The cloth was then removed and washed with deionized water. The treated fabric was then immersed in a hot bath containing KI. The bath was heated to 90 ° C. and the fabric was immersed in it for 1 hour. The KI concentration was 30% of the initial weight of the fabric added to water. The cloth was removed from the bath and washed again in water. The fabric exhibited a pale yellow color and the test showed that 10.2% of its weight was CuI adsorbed on the fiber. The electrical resistance and antibacterial properties are shown in the table after Example 6.

Example 2 An acrylic cloth was used in 0.1 liter of water, 85 cm.²Copper plate, H₂O
3% by weight of CuCl ₂And 0.15% by weight (with respect to water)
H₂SO_FourWas immersed in a hot bath containing. The weight of the cloth is for water
It was 1:40. Soak the cloth in the bath for 30 minutes at 90 ℃
Then, it was taken out and washed. The treated fabric is then heated in a hot bath (90
C.) for 1 hour. Bath is 3 wt% KI for water
Contained. When the cloth is washed after being taken out, it shows a pale yellow color.
It was The test showed that 11.5% of the fabric weight was CuI adsorbed.
Was shown. The electrical conductivity and antibacterial properties are shown in the table.

Examples 3-6 Baths containing aqueous solutions of the compounds listed in the following table were prepared. In each case, the fabric was immersed in a hot (90 ° C.) bath for 1 hour, removed, washed and then tested for CuI and CuS content, electrical conductivity and antibacterial properties. All chemical percentages are by weight with respect to fabric weight.

Example No. CuCl ₂ NaHSO ₃ Na ₂ S ₂ O ₃ KI Cloth color 3 30% 15% 27% 3% Green 4 30% 15% 9% 21% Brown 5 30% 15% 3% 27% Light brown 6 30% 15% 1% 29% Yellow The test for electrical conductivity was a standard test of the treated fabric. The antibacterial test was conducted as follows.

Firstly, Stahirococcus aureus (St
aphyrococcus aures) (S. aureus) and Trichophyton rubrum (T. rubrum) were prepared and activated as follows. S. Aureus was twice activated on nutrient agar at 35 ° C. for 24 hours and transferred to nutrient broth. After 18 hours, the broth was centrifuged to collect the bacteria, which was then washed to obtain about 10 ⁶ CFU / m 2.
Diluted to an average number of l. T. Rubrum was prepared, activated on mycological agar at 25 ° C. for 5-7 days, then transferred to another mycological agar surface and diluted to approximately 10 ⁵ CFU / ml.

The fabric to be tested (1 inch square) was then S.
Aureus 0.5 ml or T. It was added to 10 ml of the rubrum solution. After 18 hours, S. Nutrient agar and T. aureus for Aureus The number of bacteria was counted on potato dextrose agar for Rubrum. The following table shows the electrical conductivity and antibacterial properties for the fabrics treated according to Examples 1-6. Untreated control pieces were also cut for each example and tested after 18 hours.

Example Initial number of bacteria Final number Control No. type CFU / in ² CFU / in ² CFU / in ² Efficiency 1 S. aureus 1.3 × 10 ⁶ 0 7.1 × 10 ⁶ 100% T. rubrum 2.3 × 10 ⁵ 56 3.2 × 10 ⁵ 99.98% 2 S. aureus 1.3 × 10 ⁶ 0 7.1 × 10 ⁶ 100% T. rubrum 2.3 × 10 ⁵ 40 3.2 × 10 ⁵ 99.98% 3 S. aureus 1.1 × 10 ⁶ 320 6.2 × 10 ⁶ 99.97% T. Rubrum 1.6 × 10 ⁵ 620 1.3 × 10 ⁵ 99.61% 4 S. Aureus 1.1 × 10 ⁶ 340 6.2 × 10 ⁶ 99.97% T. Lubrum 1.6 × 10 ⁵ 380 1.3 × 10 ⁵ 99.76% 5 S. Aureus 1.1 × 10 ⁶ 29 6.2 × 10 ⁶ 99.99% T. rubrum 1.6 × 10 ⁵ 62 1.3 × 10 ⁵ 99.96% 6 S. aureus 1.1 × 10 ⁶ 0 6.2 × 10 ⁶ 100% T. rubrum 1.6 × 10 ⁵ 70 1.3 × 10 ⁵ 99.96 % The electrical conductivity of each treated cloth was as follows.

Initial resistance Final resistance CuI (CuS) Example Ω Ω content 1 10 ¹³ 1 × 10 ⁸ 10.2% 2 10 ¹³ 2 × 10 ⁴ 11.5% 3 10 ¹³ 500 11.9% 4 10 ¹³ 8 × 10 ³ 11.5% 5 10 ¹³ 1 × 10 ⁵ 10.9% 6 10 ¹³ 8 × 10 ⁷ 10.4% To know from the above examples that the electrical resistance and antibacterial efficiency can be modified by changing the solution concentration, which illustrates the invention and is not limited to the disclosed parameters. You can In particular, the substance concentration can be changed to modify the color, resistance and bacterial control, and the bath temperature can also be changed between about 50 and 120 ° C. as described above. The one-bath system used in Examples 3-6 can also be converted to a two-bath system as in Examples 1-2. The invention is not limited to the details described above but can be modified within the scope of the claims.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location 7199-3B D06M 21/00 D

Claims (16)

[Claims] 1. A method of treating fibers to render them both electrically conductive and antibacterial, comprising the steps of: a) preparing a first bath of an aqueous solution containing copper ions; and b) containing iodide ions. Preparing a second bath of an aqueous solution, c) immersing the fibers in the first bath in which the copper ions are adsorbed on the fibers, d) removing the fibers from the first bath Immersing the fibers in the second bath, in which iodide ions combine with the copper ions to form copper iodide adsorbed on the fibers to provide electrical conductivity and antibacterial properties of the fibers. And e) removing the fibers from the second bath. 2. The method of claim 1, wherein the first bath contains an aqueous solution of divalent copper ions and an amount of reducing agent sufficient to convert the divalent copper ions to monovalent copper ions. 3. The method according to claim 1, wherein the second bath contains an aqueous solution of a metal iodide or iodate selected from the group of substances including potassium iodide, potassium iodate, sodium iodide and sodium iodate. Method. 4. The method according to claim 1, wherein the copper ions are selected from the group of substances including copper sulfate, copper chloride and copper nitrate. 5. Step c comprises immersing the fibers in a first solution at 50-120 ° C. and step d including 50 the fibers.
Dipping in a second solution at ~ 120 ° C,
The method of claim 4. 6. The divalent copper ion is copper sulfate, copper chloride or copper nitrate, and the reducing agent is metallic copper, sodium formate, ferrous sulfate, sodium bisulfite, sodium dithionite,
The method according to claim 2, which is one of a group of substances including sodium hypophosphite, ammonium vanadate, hydroxylamine sulfate, furfural, glucose and hydroxylamine and mixtures thereof. 7. The method of claim 1, wherein the first bath, the second bath, or both contain a significant amount of sodium thiosulfate. 8. A method of treating fibers to impart electrical conductivity and antibacterial properties to the fibers, comprising the steps of: a) preparing a bath of an aqueous solution containing copper ions and iodide ions; and b) adding the fibers to the bath. D., Adsorbing copper iodide on the fibers therein, and c) removing the fibers from the bath. 9. The method of claim 8, wherein the bath comprises an aqueous solution of divalent copper ions and a reducing agent sufficient to convert the divalent copper ions to monovalent copper ions. 10. The method of claim 9, wherein the bath further comprises a substantial amount of sodium thiosulfate. 11. The method of claim 8 wherein the bath is heated to room temperature or above prior to step b. 12. The method of claim 11, wherein step b comprises immersing the fibers in a bath at 50-120 ° C. 13. The method of claim 8, wherein the fibers are washed after step c. 14. The method according to claim 10, wherein sodium thiosulfate is added to the bath in an amount of 0 to 29% by weight, based on the weight of the fibers. 15. A fiber having high electric conductivity and antibacterial property, which is produced by the method according to claim 1. 16. A fiber having a high electrical conductivity and an antibacterial property produced by the method according to claim 8.