JP2006052490A - Method for producing antibacterial fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing an antibacterial fabric having high adhesiveness of a photocatalyst without making the photocatalyst readily fall off by washing, etc. <P>SOLUTION: The method for producing the antibacterial fabric is carried out as follows. A fabric, together with a treating liquid containing a titanium oxide solution having photocatalytic actions, is charged into a rotating drum type treating machine and the rotating drum is rotated at a rotational speed so as to provide 0.2 to 1.5 G. Thereby, the fabric and the treating liquid are reciprocatively or intermittently rotated for a time sufficient to permeate the fabric with the treating liquid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing an antibacterial fabric, and more particularly to a method for producing an antibacterial fabric having excellent durability utilizing the photocatalytic action of titanium oxide.

Conventionally, antibacterial fabrics are known in which antibacterial properties are imparted by attaching a photocatalyst coating agent to fabrics used for towels, sheets, sick clothes, yukata, underwear, and the like.
As such a photocatalytic coating agent, a low-temperature coating agent containing a titanium peroxide compound is known. In order to use as a low temperature coating agent, it is necessary to be a long-term stable homogeneous solution that is neutral, has few impurities, and does not re-dissolve in the catalyst. A peroxotitanic acid aqueous solution satisfies these conditions. This peroxotitanic acid aqueous solution is synthesized by preparing components by acting H ₂ O ₂ on a titanic acid suspension or a peroxotitanium hydrate Ti ₂ O ₅ (OH) ₂ suspension prepared from a titanium salt aqueous solution. can do. By appropriately adjusting the components of this aqueous solution of peroxotitanic acid or peroxotitanium hydrate, and heating or autoclaving, a coating agent for photocatalyst called peroxo-modified anatase sol containing a little peroxotitanium can be obtained. . A peroxotitanic acid aqueous solution, a peroxo modified anatase sol, a mixture thereof, and a composite liquid with other materials are collectively referred to as a peroxotitanium-based coating agent.

  Peroxotitanium-based coatings such as those mentioned above are used as coating agents for the purpose of environmental purification such as antifouling, antibacterial, deodorant, NOx / SOx immobilization, water purification, etc. It is applied to various products as a coating agent for on-site enforcement of bodies, houses and hotels, air purification permeable tiles, deodorized air purifiers, deodorized metal filters and the like.

However, when the above coating agent is applied to towels, sheets, and other fabrics, the usual adhesion methods such as kneading, dipping, and coating have poor adhesion, and easily fall off due to washing, etc. There was a problem of being inferior.
Hiromichi Ichinose, Ceramics, 36, 586 (2001) JP 2001-46775 A

  An object of the present invention is to solve the above-mentioned problems, and to provide a method for producing an antibacterial fabric that has high photocatalytic adhesion and does not easily fall off by washing or the like.

  In order to achieve the above-mentioned object, the present inventors are diligently researching a method of attaching a titanium oxide solution to a cloth. Usually, a washing machine used for washing a contaminated cloth, particularly a wet cleaning type rotating drum. When the type washing machine was used as a treatment machine for attaching a titanium oxide solution to a fabric, surprisingly, the antibacterial fabric or its two having extremely excellent adhesion to the fabric, that is, durability such as washing resistance. The inventors have found that the following product can be obtained and have reached the present invention.

The invention claimed in the present application is as follows.
(1) The cloth is put into a rotating drum type processing machine together with a treatment liquid containing a titanium oxide solution having a photocatalytic action, and the cloth and the treatment liquid are 0.2 G to 1.5 G at the rotating drum. A method for producing an antibacterial fabric, wherein the antibacterial fabric is rotated at a rotational speed and is reciprocally or intermittently rotated for a time sufficient for the treatment liquid to penetrate into the fabric.
(2) The method according to (1), wherein the titanium oxide solution is selected from a peroxotitanic acid aqueous solution, a peroxo modified anatase sol, and a mixture thereof.
(3) The method according to (1) or (2), wherein the processing machine is a wet cleaning type rotary drum type washing machine.

  The term “fabric” used in the present invention refers to a fabric that requires action by a photocatalyst such as antibacterial properties, and secondary products such as mattresses, bed pads, curtains, sheets, diapers, sick clothes, uniforms, surgical gowns, pillow cases. , Futon cover, yukata, towel, bathrobe, cloth, tablecloth, pajamas, underwear, socks, etc. These fabrics include those obtained by graft polymerization of hydrophilic groups such as carboxyl groups in order to improve the adhesion of titanium oxide.

  The titanium oxide solution used in the present invention may be a peroxotitanium-based coating agent as described above, but is not limited to the above as long as the affinity for the fabric is also good. As such a peroxotitanium-based coating agent, a commercially available peroxotitanic acid aqueous solution, peroxo-modified anatase sol, or a mixture thereof is preferably used. A binder such as a polyurethane emulsion, a surfactant, and the like can be added to these coating agents as necessary.

  According to the present invention, the contact effect between the fabric and the treatment liquid is enhanced by the stagnation and hitting effect of the rotating drum, the treatment liquid penetrates into the interior of the fabric, and the adhesion of titanium oxide to the fabric is enhanced. The washing resistance and durability of the antibacterial fabric are remarkably improved.

Hereinafter, a washing machine used in the present invention will be described in detail with reference to the drawings.
FIG. 1 is an explanatory view showing an example of a fabric processing apparatus used in the present invention. This apparatus is mainly composed of a storage tank 1 for the processing liquid 10 and a processing tank 3 connected to the storage tank 1 via a pipe 2. The processing tank 3 is a horizontal cylinder, and includes a rotating drum 4 that is built in the processing tank 3 and cantilevered by a horizontal rotation shaft that coincides with the center of the processing tank. The rotating drum is porous so that treated water cannot flow into and out of the interior by rotation. The rotating drum is rotationally driven by an electric motor through a belt transmission device. The front surface of the rotating drum is provided with an opening for taking in and out the cloth, which is an object to be processed, and a door for covering the opening during processing. In the figure, 6 is a pipe for discharging or circulating the processing liquid, and 5, 7 and 9 are valves.

  In order to process the fabric using the processing apparatus, first, the fabric 8 that is the object to be processed is put into the rotating drum 4. Next, the valve 5 is opened, and the water to be treated is injected from the pipe 2 into the treatment tank 3 at a predetermined water level, usually at a depth at which the lower quarter or half of the rotating drum 3 is submerged. The rotating drum 4 is reciprocated or intermittently rotated for a predetermined time at a rotational speed at which the centrifugal force in the peripheral wall portion is 0.2 to 1.5 G (G is gravitational acceleration), preferably 1.1 to 1.3 G. After the processing for a predetermined time is finished, the rotation of the rotary drum 4 is stopped and the processed product is taken out. The processing liquid is discharged from the pipe 6 through the valve 7 and reused. When the processing liquid is consumed, it is replenished by that amount and stored in the storage tank 1.

  In the above processing, the rotational speed of the rotating drum (set value of 0.2 to 1.5G) and whether the rotating drum is intermittently or reciprocally rotated are appropriately selected depending on the properties of the object to be processed. If the force is less than 0.2 G, the effect of attaching titanium oxide to the fabric is inferior, and if it exceeds 1.5 G, the fabric tends to adhere to the inner wall of the rotating drum, and it becomes difficult to perform processes such as kneading and hitting. At a rotational speed at which the centrifugal force on the peripheral wall of the rotating drum is 0.2 to 1.5 G, the processed material moves in the rotating drum rotating around the horizontal axis, and processing accompanied by mechanical force such as squeezing and tapping. Is done. When the treatment with such mechanical force is performed, the treatment liquid penetrates into the details of the fabric, and the adhesion of titanium oxide and the washing resistance are improved. As a means for supplying the treatment liquid to the object to be processed in the rotating drum, a continuous type may be adopted in addition to the batch type as described above. In the case of the continuous type, a pump for circulating the solution is required. Since the treatment liquid contains titanium oxide, it is easy to cause clogging of equipment, and it is necessary to pay attention to blockage of pump piping and the like. When the processing liquid is circulated, the processing effect is further enhanced because the processing liquid renewal effect is added to the mechanical force such as kneading and hitting. The treatment time varies depending on the centrifugal force applied to the rotating drum, but may be about 5 to 30 minutes in the time required for the treatment liquid to sufficiently permeate the fabric, for example, in the range of 1 to 1.3 G.

Hereinafter, the present invention will be specifically described by way of examples.
Using a commercially available wet cleaning type rotary drum type washing machine as the fabric processing machine of the present invention, and using a commercially available peroxotitanium coating agent as the treatment liquid, the titanium oxide is attached to the fabric (towel) as shown in FIG. It was. The processing conditions are as follows.

Processing machine: Rotating drum type washing machine manufactured by Inamoto Seisakusho (trade name, Lovenet Excela IWE-50E)
Treatment liquid: A solution (1 liter) of a peroxotitanic acid aqueous solution and a peroxo modified anatase sol diluted with 300 cc of water.
Processing time: 7 to 10 minutes Centrifugal force during drum rotation: about 1.1 to 1.3 G
Treatment temperature: room temperature After the titanium oxide adhesion treatment, the fabric (towel) was dried with a roll ironer (roll iron) and a hot air dryer (tumbler) to obtain a final product.

Table 1 shows the results of the antibacterial test conducted on the following test conditions for the towel treated with the antibacterial material according to the present invention and the untreated towel (respectively, a towel after washing for 30 days).
Test bacteria: Staphylococcus aureus
Preparation of test bacteria solution: The test bacteria were inoculated into a heart infusion broth (Difco), cultured at 35 ° C. for 18 hours, and adjusted to about 10 ⁶ cells / ml.
Test method: 1 ml of the prepared bacterial solution was inoculated into the test sample, and sterilized purified water was placed around it to prevent drying. This was irradiated with black light in a constant temperature incubator at 35 ° C. for 24 hours, and then the viable cell count was measured by culturing on a normal agar medium (manufactured by Nissui Pharmaceutical) at 35 ° C. for 24 hours.

  From the above results, it can be understood that the towel of the present invention completely sterilizes the bacteria, but the towel of the untreated product has grown the bacteria. In addition, the product of the present invention does not lose titanium oxide even after 30 times of water washing (usual use of a household washing machine), and the bacteria are completely sterilized. It can be seen that although the titanium oxide almost dropped off and suppressed the growth of bacteria, the bactericidal effect was lost.

  In addition, when the deodorizing property test for ammonia, acetic acid and hydrogen sulfide of the product of the present invention (the towel of the example) was performed, the concentration of 40 ppm after 0.7 hours was 0.7 ppm for ammonia, and the concentration of 100 ppm after 24 hours for acetic acid. The concentration was reduced to 0.6 ppm, and a deodorizing effect was clearly observed.

Since the towels of the present invention are post-processed, the type of yarn is not selected, and the product of a deodorant yarn kneaded with a deodorant and photocatalyst processing cancels the performance of the deodorant yarn. High antibacterial properties and high deodorizing properties can be imparted simultaneously. For example, the product of the present invention has little deodorizing effect on hydrogen sulfide, but by using a yarn kneaded with a deodorizing agent, the deodorizing property and antibacterial property can be simultaneously obtained without hindering the effect of photocatalytic processing. Can be granted.
Further, a skin patch test using a closed patch was performed on the product of the present invention (the towel of the example), but no irritation to human skin was observed.

  The present invention is useful for imparting antibacterial properties to fabrics such as towels, sheets, sick clothes, yukata, underwear, and secondary products thereof.

Explanatory drawing which shows an example of the fabric processing apparatus used for this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Storage tank, 2 ... Piping, 3 ... Processing tank, 4 ... Rotary drum, 6 ... Piping for discharge | emission or circulation, 5, 7, 9 ... Valve, 8 ... Fabric, 10 ... Processing liquid.

Claims (3)

The fabric is put into a rotating drum type processing machine together with a treatment liquid containing a titanium oxide solution having a photocatalytic action, and the cloth and the treatment liquid are fed at a rotational speed of 0.2 G to 1.5 G. A method for producing an antibacterial fabric, wherein the antibacterial fabric is rotated and reciprocally or intermittently rotated for a time sufficient for the treatment liquid to penetrate into the fabric. 2. The method according to claim 1, wherein the titanium oxide solution is selected from a peroxotitanic acid aqueous solution, a peroxo modified anatase sol, and a mixture thereof. 3. The method according to claim 1, wherein the processing machine is a wet cleaning type rotary drum type washing machine.

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