OF PREPARING THE SAME AND ANTIBACTERIAL FIBER THEREBY

TECHNICAL FIELD

The present invention relates to anti-bacterial acid dyes

containing silver which are prepared by combining silver-containing

sulfonamides as strong anti-bacterial reactant groups with any of

naphthalene based dye intermediates and a preparation method thereof,

and an an ti- 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 garments, bedding, etc.

needs to undergo a fiber material dyeing process with desired colors to

satisfy various tastes of consumers.

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 antibacterial 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 antibacterial 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, the organometallic compounds applied in a fiber processing 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 poor 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 anti-bacterial effect is not 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 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 copper and zinc belong to a few metals with superior anti-bacterial effects and safety, and are harmless to the human body. The inorganic antibacterial 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 antibacterial 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, 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 anti-bacterial 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. Specifically, the present invention provides an anti¬

bacterial acid dye containing silver, in which a naphthalene based dye intermediate is bonded to silver sulfadiazine containing silver ions Ag ⁺

by azo-coupling reaction. 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 the above 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 represented by the following chemical formula 1 below, in which a naphthalene based dye intermediate is bonded to a

silver-containing sulfonamide, that is, a sulfonamide based anti¬

bacterial agent containing silver by azo-coupling reaction, and an anti- bacterially functional fiber dyed by the same: Chemical formula 1

(wherein A is a naphthalene based dye intermediate) .

More particularly, the above silver-containing acidic dye has any of structures represented by the following chemical formulae 2 and

3:

(wherein R ₁ is H, SO ₃ Na or SO ₃ H; R is H or OH; and R ₃ is H,

OH or NH ₂ ).

Chemical formula 3

(wherein Ri is H, OH, NH2, NHCH ₃ , aminophenyl, SO ₃ Na or SO ₃ H; R ₂ and Re are independently H, SO ₃ Na or SO ₃ H; R ₃ is H or NH ₂ ;

R ₄ is SO ₃ Na, SO ₃ H, H or OH; R ₅ is SO ₃ Na, SO ₃ H or NHSO ₂ CH ₃ ; and R ₇

is H, NH ₂ , OH or NHCOCH ₃ ).

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, particularly, sulfonamide based anti-bacterial agents containing silver

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 meninggococci, 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 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, silver sulfadiazine, sulfamerazine, sulfamethoxine, sulfapyrazine, phthalylsulfathiazole, sulfathiazole, mafenide, sulfadimidine, sulfamethazine, sulfamethoxazole, sulfanilamide, sulfamethoxypyridazine, sulfaguanidine,

sulfadimethoxine, sulfisoxazole, sulfadoxine, sulfamethizole,

sulphasalazine, sulphinpyrazone, etc.

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 the sulfonamide based anti-bacterial agents containing silver that are mostly available as intermediates of dyes

easily synthesized and exhibit excellent anti-bacterial effect:

General formula 1 : silversulfadiazine

Silversulfadiazine is one of sulfadiazine derivatives, it 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 2 according to the present invention. More particularly, the present invention provides the anti-bacterial acid dye represented by the following chemical formula 2 synthesized by (a) conducting diazotization of silversulfadiazine represented by the following general formula 1 with hydrochloric acid and sodium nitrite, then, (b) activating azo-coupling reaction of the resulting product with 5-hydroxynaphthalene- 1 -sulfonic acid represented by the following general formula 2, or 4-amino-5-hydroxynaphthalene- l,7-disulfonic acid represented by the following general formula 3. General formula 1 : silversulfadiazine

General formula 2: 5-hydroxynaphthalene- 1 -sulfonic acid

General formula 3: 4-amino-5-hydroxynaphthalene- l,7-

disulfonic acid

Chemical formula 2

(wherein Ri is H, SOsNa or SO3H; R ₂ is H or OH; and R3 is H, OH or NH ₂ ).

A preferred embodiment of the present invention comprises an anti-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

10 formula 1 among the 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 5-hydroxynaphthalene- 1 -sulfonic acid represented by the following general formula 2 through azo-coupling reaction.

J 5

General formula 1 : silversulfadiazine

General formula 2: 5-hydroxynaphthalene- 1 -sulfonic acid

Chemical formula 4

(wherein Sθ3Na may be substituted by SO3H) .

Another 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 4-amino-5-hydroxynaphthalene- l,7-disulfonic acid

represented by the following general formula 3 through azo-coupling

reaction.

General formula 1 : silversulfadiazine

General formula 4-amino-5-hydroxynaphthalene- 1 ,7-

disulfonic acid

Chemical formula 5

(wherein SOaNa may be substituted by SO3H).

In the following, detailed description is given of a method for

preparing the anti-bacterial acid dye containing silver represented by

the above chemical formula 3 according to the present invention. More

particularly, the present invention provides the anti-bacterial acid dye represented by the following chemical formula 3 which is synthesized by (a) conducting diazotization of silversulfadiazine represented by the following general formula 1 with hydrochloric acid and sodium nitrite, then, (b) proceeding azo-coupling reaction of the resulting product with

any one compound selected from a group consisting of: 7-

aminonaphthalene- l,3,6-trisulfonic acid represented by the general formula 4; 4-hydroxynaphthalene- l -sulfonic acid represented by the general formula 5; N-(7-hydroxynaphthalene- l-yl)-acetamide

represented by the general formula 6; aminonaphthalene represented

by the general formula 7; hydroxynaphthalene represented by the

general formula 8; 7-aminonaphthalene-4-sulfonic acid represented by

the general formula 9; 2,7-diaminonaphthalene represented by the general formula 10; 4-amino- l-hydroxynaphthalene-6-sulfonic acid

represented by the general formula 1 1; 4-hydroxy-7-phenylamino- naphthalene-2-sulfonic acid represented by the general formula 12; 4-

hydroxy-6-methylamino-naphthalene-2-sulfonic acid represented by the

general formula 13; and N-(6-amino-naphthalene-2-yl)-methane

sulfonamide represented by the general formula 14. General formula 1 : silversulfadiazine

General formula 4: 7-aminonaphthalene-l,3,6-trisulfonic acid

General formula 5: 4-hydroxynaphthalene- 1 -sulfonic acid

General formula 6: N-(7-hydroxynaphthalene-l-yl)-acetamide

CH ₃

General formula 7: aminonaphthalene

General formula 8: hydroxynaphthalene

General formula 9: 7-aminonaphthalene-4- sulfonic acid

General formula 10: 2,7-diaminonaphthalene

General formula 11: 4-ammo-l-hydroxynaphthalene-6- sulfonic acid

General formula 12: 4-hydroxy-7-phenylamino-naphthalene-

]() 2 -sulfonic acid

General formula 13: 4-hydroxy-6-methylamino-naphthalene- 2 -sulfonic acid

General formula 14: N-(6-aminonaphthalene-2-yl)-methane

sulfonamide

Chemical formula 3

(wherein R ₁ is H, OH, NH2, NHCH ₃ , aminophenyl, Sθ3Na or

SO ₃ H; R ₂ and R ₆ are independently H, SO ₃ Na or SO ₃ H; R ₃ is H or NH ₂ ; R ₄ is SO ₃ Na, SO ₃ H, H or OH; R ₅ is H, SO ₃ Na, SO ₃ H or NHSO ₂ CH ₃ ; and R ₇ is H, NH ₂ , OH or NHCOCH ₃ ).

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 7-aminonaphthalene- l,3,6-trisulfonic acid represented by the following general formula 4 through azo-coupling reaction.

General formula 1 : silversulfadiazine

General formula 4: 7-aminonaphthalene-l,3,6-trisulfonic acid

Chemical formula 6

(wherein SOeNa may be substituted by SO3H).

Still a further preferred embodiment of the present invention comprises an anti-bacterial acid dye containing silver represented by the following chemical formula 7 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 4-hydroxynaphthalene~ l-trisulfonic acid represented by the following general formula 5 through azo-coupling reaction.

General formula 1: silversulfadiazine

General formula 5: 4 -hydroxy naphthalene- 1 -sulfonic acid

Chemical formula 7

(wherein SOsNa may be substituted by SO3H).

(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

10 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.

I T) 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 anti- bacterial effect for 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 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 NaNO2 to proceed diazotization represented by the following reaction scheme 1 : (Reaction scheme 1)

In an alternative reaction vessel, 0.02 moles of 5- hydroxynaphthalene- 1 -sulfonic acid represented by the general formula 2 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 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 blue color represented by the chemical formula 4 above according to the present invention.

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 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 5]

(Chemical formula 5)

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 4-amino-5- hydroxynaphthalene- 1 ,7-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 an ti- bacterial acid dye with blue color

represented by the chemical formula 5 above according to the present invention.

To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 5, 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 6] (Chemical formula 6)

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 5:

(Reaction scheme 5)

In alternative reactor, 0.02 moles of 7-aminonaphthalene- 1,3,6-trisulfonic acid represented by the general formula 4 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)

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 6 above according to the present invention.

To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 6, 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 4: Preparation of an anti-bacterial acid dye containing silver represented by the chemical formula 7]

(Chemical formula 7)

(wherein SOβNa 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 7:

(Reaction scheme 7)

In alternative reactor, 0.02 moles of 4-hydroxynaphthalene- l-

sulfonic acid represented by the general formula 5 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 8.

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 7 above according to the present

invention.

To 1.0% aqueous solution containing the obtained acid dye compound of the chemical formula 5, 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. (Reaction scheme 8)

Evaluation of anti-bacterial properties Plain woven nylon fabric which was dyed with a concentration of 1% o.w.f. (on the weight of fiber) using each of the yellow and 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 anti-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 - Staphylococcus 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

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

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

Industrial Applicability

As described in detail above, the anti-bacterial acid dye of the present invention enables production of anti-bacterially functional fiber products 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.

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.