TECHNICAL FIELD

The present invention relates to anti-bacterial agents based on sulfonamides as strong anti-bacterial reactant groups, and more particularly, to anti-bacterial acid dyes containing silver which are prepared by combining silver-containing sulfonamides with any of intermediates of dyes and a preparation method thereof, and an anti- bacterial fiber with a wide range of colors and improved anti-bacterial properties, which is produced by dyeing with the above silver-containing anti-bacterial acid dyes.

Generally, a fabric product used in garment, bedding, etc. needs to undergo a fiber material dyeing process with desired colors to satisfy various tastes of consumer.

Such manufactured fabric products often become habitable for microorganisms due to poor care, allowing the microorganisms to inhabit and grow with normal bodily secretions as nutrients when the microorganisms contact directly with a human body so that they threaten health of the human body and/ or result in bad odor, contamination, discoloration, brittleness of fiber, etc., thereby being a major cause to deteriorate quality of the fabric product such as durability, color fastness or the like.

Accordingly, the fabric product may become a medium or habitat for pathogenic bacteria to invade the human body. However, if the fabric product has anti-bacterial properties, it will become a functional fabric product that inhibits inhabitation or growth of microorganisms and, as a result, protects against contagious disease and bad odor, and prevents staining and brittleness of fiber of the fabric product.

BACKGROUND ART

It is well known that anti-bacterial and moth-proofing processes are generally classified into post-treatment processes and fiber improving processes. The post-treatment processes include: as disclosed in Korean Patent Laid-Open No. 2000-007593, a method for

giving anti-bacterial properties to fibers, which includes extraction of dyeing ingredient from a natural material such as Saururus chinensis (Lour.) Baill with anti-bacterial properties; a method which cross-links an anti-bacterial material such as organometallic compound or organic material with fibers and thermally fixes the bonded product to surface of the fibers by using a reactant resin; a method which fixes an anti- bacterial material to surface of fibers by adsorption and so on. On the other hand, the fiber improving processes include: a method which comprises introducing an inorganic anti-bacterial agent into fibers by blend- spinning the inorganic anti-bacterial agent into polymer in a

process of manufacturing synthetic fibers; a method which disperses a copper compound into fibers during coagulating and regenerating in a process of manufacturing regenerated fibers; a method for synthesizing

polymer, which comprises organic copolymer ingredients with anti- bacterial properties and so on.

The anti-bacterial and moth-proofing processes are not for a purpose of sterilization or treatment of diseases but are to inhibit inhabitation and growth of microbes and/or fungi on fibers. Therefore, the processes require that an anti-bacterial effect is continuously

maintained at least a predetermined level rather than only exhibiting high anti-bacterial properties for a short time and must also be safe to human bodies. Under these circumstances, although organic mercury compound, organic tin compound, organic copper compound and organic zinc compound among the organometallic compounds used in the post-treatment processes have very superior anti-bacterial properties, they also have a problem of safety to a human body such as toxicity. As a result, most of the organometallic compounds for garments are prohibited in countries such as Japan, U.S.A., etc. but are partially used in applications that do not involve direct contact with the human body, for example, production of carpet or wallpaper, or other industrial fields. Furthermore, such organometallic compounds that have demonstrated problems of undesired adhesion to fibers and low laundry durability are restricted in their permanent anti-bacterial effect.

Also, general organic anti-bacterial materials that can be easily- processed compared with inorganic materials and do not affect mechanical properties, transparency, color, etc., as much, are widely

used at present. However, use of the organic anti-bacterial materials is limited because their an ti- bacterial effect is not continued for a long term as described above and they have inferior heat-resistance. Alternatively, some of the organic anti-bacterial materials often have disadvantages of causing skin irritation, tearing property and so on. Dyes extracted from natural materials have a merit that anti-bacterial properties are given to fibers early in a dyeing process. But, they have a restriction in extracting the dyes due to seasonal limitation and a disadvantage that mordant dyeing accompanied with additional heavy metals is required to improve color fastness as a defect of natural dyes.

Inorganic anti-bacterial materials are obtained by substitution of an inorganic carrier such as zeolite, silica, alumina, etc. with metal ions such as silver, copper, zinc, etc. having excellent anti-bacterial properties. The inorganic anti-bacterial materials that have three- dimensional structure formed with micro-fine pores demonstrate a large surface area and excellent heat-resistance. It is believed as of now that silver, copper and zinc belong to a few metals with superior antibacterial effect and safety, and are harmless to the human body. The inorganic anti-bacterial materials have higher heat-resistance and stability sufficient not to cause volatilization and decomposition thereof

in comparison to conventional organic anti-bacterial materials, thereby being used in a wide variety of applications. In addition, since they express anti-bacterial effect via activated oxygen ions, the inorganic

anti-bacterial materials have an excellent anti- bacterial effect superior to the organic anti-bacterial materials. However, such metal ions, for example, silver, copper or zinc that are apt to deteriorate resin or cause yellowing have a possibility of significantly lowering value of goods containing the same. There is another concern with the inorganic antibacterial materials in that they may cause cutting of thread if the

inorganic anti-bacterial materials are added to micro-fine fibers during blend-spinning, since they generally have a larger average particle diameter above micron units and a wider distribution of particle size called 'fineness'.

DISCLOSURE OF THE INVENTION

(TECHNICAL PROBLEM)

Accordingly, the present invention is directed to solve the problems of conventional anti-bacterial materials used as dyes as described above and, an object of the present invention is to provide an acidic dye containing strong anti-bacterial reactant groups and a preparation method thereof. After extensive research and investigation to achieve the above object, the present inventors have found that the anti-bacterial effect activated by silver ions Ag ⁺ increases synergistically

with the anti-bacterial effect of sulfonamides, and completed the

present invention by using silversulfadiazine containing silver ions Ag ⁺ .

Specifically, the present invention provides a method for preparing anti-bacterial acid dyes by introducing silversulfadiazine among sulfonamide based anti-bacterial agents with the excellent anti¬

bacterial function to precursors of acidic dyes.

Also, it is another object of the present invention to provide an

anti-bacterial fiber with advantages, such as, that it needs no alternative process for obtaining anti-bacterial properties by dyeing the

fiber with an anti-bacterial acid dye containing silver, exhibits no

discoloring of woven fabric and/ or knitted fabric by decomposition of the dye, and demonstrates anti-bacterial properties and excellent durability for maintaining long term anti-bacterial effect.

(TECHNICAL MEANS TO SOLVE THE PROBLEM)

In accordance with the present invention, there are provided an anti-bacterial acid dye containing silver represented by the following

chemical formula 1 below, which has silver-containing sulfonamide as a diazo compound, and a preparation method thereof. Also, the present invention provides an anti-bacterially functional fiber dyed by the anti-bacterial acid dye containing silver, which exhibits a wide range of colors and improved anti-bacterial properties simultaneously.

Chemical formula 1

(wherein R ₁ is H, NH ₂ or OH; R ₂ is H, Cl, SO ₃ Na or SO ₃ H; R ₃ is H, NHCOCH ₂ COCH ₃ , NHCONH ₂ , NH ₂ or N(CH ₂ CH ₃ J ₂ ; and R ₄ is H, SO ₃ Na or SO ₃ H).

The present invention will be described in detail below. Anti-bacterial materials generally used include, for example, penicillin, sulfonamide, fluoroquinolone, tetracycline, aminoglucoside and the like. Among them, preferred are tetracycline, sulfonamide, quinolone, etc. which are widely and commercially available as intermediates of dyes.

Of these materials, sulfonamide based anti-bacterial agents that endow anti-bacterial properties to a subject matter by inhibiting metabolism functions of enzymes in microorganisms such as synthesis of nucleic acid have been used in the present invention.

Sulfonamide drug, that is, the sulfonamide based anti-bacterial agent is one of anti-bacterial agents having SO2NH2 group and is used as a general term for sulfanilamide derivatives that disrupt folic acid synthesis in the microorganisms. The above anti-bacterial agent is one of anti-bacterial materials that inhibit growth of bacteria including: for example, gram-positive cocci such as streptococci, pneumococci; gram-

negative cocci such as meningococci, gonococci; gram-positive bacillus such as Escherichia coli, shigellae; and the like. Since it had been

initially found that Prontosil® rubrum developed by Gerhard Domagk, a

German scientist, in 1932 was in vivo metabolized into sulfanilamide to

f) express strong anti-bacterial effect, a number of derivatives have been synthesized. Sulfonamide commonly has a molecular structure of sulfanilamide and includes varied kinds of compounds. Sulfonamide

based anti-bacterial materials include, but are not limited to,

sulfapyridine, sulfadiazine, silversulfadiazine, sulfamerazine,

10 sulfamethoxine, sulfapyrazine, phthalylsulfathiazole, sulfathiazole, mafenide, sulfadimidine, sulfamethazine, sulfamethoxazole, sulfanilamide, sulfamethoxypyridazine, sulfaguanidine, sulfadimethoxine, sulfisoxazole, sulfadoxine, sulfamethizole,

sulphasalazine, sulphinpyrazone, etc.

I f) The present invention is applied to synthesis of anti- bacterial

acid dyes by using silversulfadiazine(monosilver-4-amino-N- pyrimidylbenzene sulfonamide) represented by the following general formula 1 among sulfonamide based anti-bacterial agents containing

silver that are mostly available as intermediates of dyes easily

20 synthesized and exhibit excellent anti-bacterial effect: General formula 1 : silversulfadiazine

Silversulfadiazine is one of sulfadiazine derivatives, exhibits anti-bacterial properties against yeast as well as numerous gram- positive and gram-negative microorganisms and is used as a locally and

externally applied anti-infectious disease agent effective to protect and treat sepsis of second and /or third degree burns.

In the following, detailed description is given of a method for preparing the anti-bacterial acid dye containing silver represented by the following chemical formula 1 according to the present invention. More particularly, the present invention provides the anti-bacterial acid dye represented by the following chemical formula 1 synthesized by (a) a first step of conducting diazotization of silversulfadiazine represented by the following general formula 1 with hydrochloric acid and sodium nitrite, and (b) a second step of proceeding azo-coupling reaction of the resulting product with any one compound selected from a group consisting of: 3-aminophenylurea represented by the following general formula 2; 2-aminobenzene- l,4-disulfonic acid represented by the following general formula 3; 3-oxo-N-phenyl-butyramide represented by the following general formula 4; N-(2-chloro-phenyl)-3-oxo-butyramide represented by the following general formula 5; and 3- diethylaminophenol represented by the following general formula 6. General formula 1 : silversulfadiazine

General formula 2: 3-aminophenylurea

General formula 3: 2-aminobenzene-l,4-disulfonic acid

General formula 4: 3-oxo-N-phenyl-butyramide

General formula 5: N-(2-chloro-phenyl)-3-oxo-butyramide

General formula 6: 3-diethylaminophenol

Chemical formula 1

(wherein R ₁ is H, NH ₂ or OH; R ₂ is H, Cl, SO ₃ Na or SO ₃ H; R ₃ is

H, NHCOCH ₂ COCH ₃ , NHCONH ₂ , NH ₂ or N(CH ₂ CHs) ₂ ; and R ₄ is H, SO ₃ Na Or SO ₃ H). A preferred embodiment of the present invention comprises an anti-bacterial acid dye containing silver represented by the following chemical formula 2 which is obtainable by: a first step of conducting diazotization of silversulfadiazine represented by the following general

formula 1 among sulfonamide based anti-bacterial agents containing silver, as a dye intermediate, with hydrochloric acid and sodium nitrite; and a second step of combining the resulted product with 3- aminophenylurea represented by the following general formula 2 through azo-coupling reaction.

General formula 1 : silversulfadiazine

General formula 2: 3-aminophenylurea

Chemical formula 2

Another preferred embodiment of the present invention comprises an anti-bacterial acid dye containing silver represented by

the following chemical formula 3 which is obtainable by: a first step of conducting diazotization of silversulfadiazine represented by the following general formula 1 among sulfonamide based anti-bacterial agents containing silver, as a dye intermediate, with hydrochloric acid and sodium nitrite; and a second step of combining the resulting product with 2-aminobenzene-l,4-disulfonic acid represented by the following general formula 3 through azo-coupling reaction. General formula 1 : silversulfadiazine

General formula 3: 2-aminobenzene-l,4-disulfonic acid

Chemical formula 3

(wherein SOβNa may be substituted by SO3H).

A further preferred embodiment of the present invention comprises an an ti- bacterial acid dye containing silver represented by the following chemical formula 4 which is obtainable by: a first step of conducting diazotization of silversulfadiazine represented by the

following general formula 1 among sulfonamide based anti- bacterial agents containing silver, as a dye intermediate, with hydrochloric acid and sodium nitrite; and a second step of combining the resulting product with 3-diethylaminophenol represented by the following general

10 formula 6 through azo-coupling reaction.

General formula 1 : silversulfadiazine

General formula 6: 3-diethylaminophenol

If) Chemical formula 4

A further preferred embodiment of the present invention comprises an anti-bacterial acid dye containing silver represented by

the following chemical formula 5 which is obtainable by: a first step of conducting diazotization of silversulfadiazine represented by the following general formula 1 among sulfonamide based anti-bacterial agents containing silver, as a dye intermediate, with hydrochloric acid and sodium nitrite; and a second step of combining the resulting product with 3-oxo-N-phenyl-butyramide represented by the following general formula 4 through azo-coupling reaction.

General formula 1 : silversulfadiazine

General formula 4: 3-oxo-N-phenyl-butyramide H ₂ COCH ₃

Chemical formula 5

Still a further preferred embodiment of the present invention comprises an anti-bacterial acid dye containing silver represented by the following chemical formula 6 which is obtainable by: a first step of conducting diazotization of silversulfadiazine represented by the following general formula 1 among sulfonamide based anti-bacterial

agents containing silver, as a dye intermediate, with hydrochloric acid and sodium nitrite; and a second step of combining the resulting

product with N-(2-chloro-phenyl)-3-oxo-butyramide represented by the following general formula 5 through azo-coupling reaction.

General formula 1 : silversulfadiazine

General formula 5: N-(2-chloro-phenyl)-3-oxo-butyramide

Chemical formula 6

(ADVANTAGEOUS EFFECTS)

As described in detail above, the anti-bacterial acid dye compounds of the present invention which have various colors can express a wide range of colors when they are used in combination, and be utilized to produce an anti-bacterially functional fiber product dyed by the same that exhibits strong anti-bacterial properties to inhibit inhabitation or growth of microorganisms and, as a result, protects

against contagious disease and bad odor and prevents staining and brittleness of fiber of the fiber product.

The present invention enables production of the anti-bacterial fiber product with advantages that it endows anti-bacterial properties early during a dyeing process, needs no alternative process for providing anti-bacterial properties, exhibits no discoloring of woven fabric and/ or knitted fabric caused by decomposition of dyes, and demonstrates antibacterial properties and excellent durability for maintaining antibacterial effect for a long term. Features of the present invention described above and other advantages will be more clearly understood by the following non-limited examples, which are not intended to restrict the scope of the invention but are instead illustrative embodiments of the present invention. Accordingly, it will be obvious to those skilled in the art that the present invention is not restricted to the specific matters stated above and the examples below.

BEST MODE FOR CARRYING OUT THE INVENTION

[Example 1: Preparation of an anti-bacterial acid dye containing silver represented by the chemical formula 2] (Chemical formula 2)

After dispersing 0.02 moles of silversulfadiazine in distilled water at 5°C or below, 6ml of hydrochloric acid HCl was added and dissolved while stirring. To the obtained solution, slowly added was 0.02 moles of sodium nitrite NaNO2 to proceed diazotization represented by the following reaction scheme 1 :

(Reaction scheme 1)

In an alternative reaction vessel, 0.02 moles of 3- aminophenolurea represented by the general formula 2 and 0.01 moles of hydrochloric acid HCl were dissolved in distilled water and

maintained at 5°C or below.

To this solution, slowly added was the diazo solution previously obtained to proceed azo-coupling reaction represented by the following reaction scheme 2:

(Reaction scheme 2)

After completing the reaction, the resulting solution was titrated to adjust pH value to 7, filtered using a filter paper after salting out and dried to yield an anti-bacterial acid dye with yellow color represented by the chemical formula 2 above according to the present invention.

To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 2, glacial acetic acid and a dispersing agent were added to produce a dye solution. After dyeing a fiber with the dye solution at 130 ⁰ C for 60 minutes, the dyed fiber was then soaped and dried to yield an anti-bacterial color fiber.

[Example 2: Preparation of an anti-bacterial acid dye containing silver represented by the chemical formula 3] (Chemical formula 3)

(wherein SOsNa may be substituted by SO3H).

After dispersing 0.02 moles of silversulfadiazine in distilled water at 5°C or below, 6ml of hydrochloric acid HCl was added and dissolved while stirring. To the obtained solution, slowly added was 0.02

moles of sodium nitrite NaNO2 to proceed diazotization represented by the following reaction scheme 3:

(Reaction scheme 3)

In an alternative reaction vessel, 0.02 moles of 2- aminobenzene- 1 ,4-disulfonic acid represented by the general formula 3 and 0.01 moles of sodium carbonate Na2CO3 were dissolved in distilled

water and maintained at 5°C or below.

To this solution, slowly added was the diazo solution previously obtained to proceed azo-coupling reaction represented by the following reaction scheme 4:

(Reaction scheme 4)

After completing the reaction, the resulting solution was

titrated to adjust pH value to 7, filtered using a filter paper after salting out and dried to yield an anti-bacterial acid dye with yellow color represented by the chemical formula 3 above according to the present invention.

To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 3, glacial acetic acid and a dispersing agent were added to produce a dye solution. After dyeing a fiber with the dye solution at 130 ⁰ C for 60 minutes, the dyed fiber was soaped and dried to yield an anti-bacterial color fiber. [Example 3: Preparation of an anti-bacterial acid dye containing silver represented by the chemical formula 4] (Chemical formula 4)

After dispersing 0.02 moles of silversulfadiazine in distilled water at 5°C or below, 6ml of hydrochloric acid HCl was added and dissolved while stirring. To the obtained solution, slowly added was 0.02 moles of sodium nitrite NaNU2 to proceed diazotization represented by the following reaction scheme 5: (Reaction scheme 5)

In an alternative reaction vessel, 0.02 moles of 3-

diethylaminophenol represented by the general formula 6 and 0.01

moles of sodium carbonate Na2CO3 were dissolved in distilled water and maintained at 5°C or below.

To this solution, slowly added was the diazo solution previously

obtained to proceed azo-coupling reaction represented by the following reaction scheme 6:

(Reaction scheme 6)

K) After completing the reaction, the resulting solution was titrated to adjust pH value to 7, filtered using a filter paper after salting

out and dried to yield an anti-bacterial acid dye with red color

represented by the chemical formula 4 above according to the present invention. la To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 4, glacial acetic acid and a dispersing agent were added to produce a dye solution. After dyeing a fiber with the dye solution at 130 ⁰ C for 60 minutes, the dyed fiber was soaped and dried to yield an anti-bacterial color fiber.

Evaluation of anti-bacterial properties

Plain woven nylon fabric which was dyecl with a concentration of 1% o.w.f. (on the weight of fiber) using each of the red color dyes previously synthesized was tested for anti-bacterial properties by KS K- 0693-2001 as a test method for anti-bacterial properties of fabric. The result is shown in Table 1 that represents anti-bacterial effect of the an ti- bacterial acid dyes containing silver according to the present invention.

Table 1

Anti-bacterial properties test

Conditions of the test for determining anti-bacterial properties of the anti-bacterial fiber containing silver are as follows:

1. type of strain:

1) strain 1 - Straphylococcus aureus ATCC 6538, 2) strain 2 - klebsiella pneumoniae ATCC 4352

2. concentration of inoculum:

1) strain 1 - 1.3 X 10 ⁵ numbers/ml, 2) strain 2 - 1.5 X 10 ⁵ numbers /ml

3. increasing rate:

1) strain 1 - 34 fold increase, 2) strain 2 - 32 fold increase

4. control sample: nylon (KS K 0905-1996)

5. non-ionic surfactant: Tween 80 (0.05%)

INDUSTRIAL APPLICABIILITY As described in detail above, the anti- bacterial acid dye of the present invention having yellow color expresses a wide range of colors when two or more of the dyes are used in combination, and enables production of anti-bacterially functional fiber products dyed by the same that exhibit strong anti- bacterial properties to inhibit inhabitation or growth of microorganisms and, as a result, protect against contagious disease and bad odor and prevent staining and brittleness of fiber.

While the present invention has been described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various modifications and variations may be made therein without departing from the scope of the present invention as defined by the appended claims.