JPH04257369A - Antimicrobial polyester yarn - Google Patents

Abstract

PURPOSE:To obtain the title white-based yarn showing antimicrobial performance with excellent durability with a small amount of a ceramic-based antimicrobial agent by adding the antimicrobial agent consisting essentially of magnesia to a polyester yarn during spinning to give yarn and subjecting the yarn to alkali weight loss treatment. CONSTITUTION:For example, a polyester yarn obtained by kneading polyethylene terephthalate with a ceramic-based antimicrobial agent consisting essentially of magnesia and subjecting to melt spinning is knitted and then subjected to alkali weight loss processing to give white antimicrobial polyester cloth showing semipermanently excellent antimicrobial ability and with no coloring. Moreover, the amount of the antimicrobial agent added is effectively smaller than that of existing method.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to polyester fibers having antibacterial properties.

0002

BACKGROUND OF THE INVENTION In recent years, with the improvement of living standards and the spread of hygienic ideas seeking a more comfortable living environment, the demand for antibacterial fibers has been increasing. Antibacterial fibers are used in futons, sheets, mats, towels, shirts, pants, socks, curtains, filters, insoles, working wear,
It has now become indispensable in a wide range of fields such as office uniforms, white coats, and other sanitary materials.

[0003] Methods for obtaining antibacterial fibers are broadly divided into methods in which antibacterial agents are added to the fibers (products) through post-processing, and methods in which antibacterial agents are added to the fibers (products) during the manufacturing stage of the yarn or raw cotton.

The former method is mainly applied to natural fibers such as cotton, and involves applying antibacterial and deodorant processing agents such as silicon-containing quaternary ammonium salts and polyoxyethylene trialkylammonium chloride to the fiber surface through covalent bonds, ionic bonds, or This is done by immobilization by physical adsorption.

On the other hand, the latter is mainly applied to synthetic fibers such as polyester and nylon, and the chemicals used in this case need to have heat resistance to withstand the temperature during melt spinning. However, very few organic compounds have been put into practical use, and inorganic compounds such as antibacterial zeolites and copper or copper compounds are mainly used.

Among them, natural or synthetic zeolite is used as a carrier, and some or all of the metals that can be ion-exchanged in the zeolite are selected from silver, copper, zinc, mercury, tin, lead, bismuth, cadmium, and chromium, which have bactericidal properties. Antibacterial zeolites substituted with one or more selected metal ions are widely used. The antibacterial mechanism of antibacterial zeolite is said to be due to metal ions dissociated and eluted from antibacterial zeolite.

However, this antibacterial zeolite has the following drawbacks. (1) When silver is the main ingredient, which has the strongest antibacterial properties, the amount of silver added is naturally limited because it is affected by ultraviolet rays and becomes colored. (2) Since it is a metal ion-eluting antibacterial agent, its antibacterial activity gradually decreases with repeated washing, and its durability is insufficient. (3) It has poor acid resistance and alkali resistance, and in pH ranges other than 3 to 9, the basic skeletal structure of zeolite itself may be destroyed, or even if it is not destroyed, antibacterial metal ions may be eluted under strong acidity. Under alkaline conditions, poorly soluble oxides, basic salts, etc. may precipitate, and the original antibacterial performance is lost. (4) It is expensive.

[0008] Copper and copper compounds are used in the form of copper fine powder, cuprous oxide, copper oxide, copper sulfide, copper sulfide, copper chloride, copper bromide, copper sulfate, copper nitrate, copper hydroxide, etc. However, its biggest drawback is that because it is colored, white fibers, which are a symbol of cleanliness, cannot be obtained.

[0009] Recently, ceramics containing magnesia as a main component have been proposed as antibacterial agents that do not have such drawbacks. However, since this ceramic is non-leaching type, simply kneading a small amount of it into a synthetic fiber such as polyester and spinning it will not produce a fiber with sufficient antibacterial performance. Adding large amounts of antibacterial agents improves antibacterial performance, but adding large amounts of such antibacterial agents during the fiber spinning process not only impairs yarn quality performance but also significantly impairs economic efficiency. .

0010

[Problems to be Solved by the Invention] As mentioned above, various attempts have been made to impart antibacterial properties to synthetic fibers such as polyester during the spinning process, but so far none have been found to be cost-effective and effective. A white polyester fiber with semi-permanent and excellent antibacterial properties has not been known.

[0011] The present invention uses a ceramic antibacterial agent containing magnesia as a main component, and provides a polyester fiber with excellent cost performance that exhibits extremely excellent antibacterial performance even in a relatively small amount. be.

[0012] Furthermore, the present invention can maintain its antibacterial properties semi-permanently even after repeated washing, has light resistance (ultraviolet resistance), does not become colored by light, and remains white forever. The aim is to provide antibacterial polyester fibers that can maintain the

[0013]

[Means for Solving the Problems] As a result of intensive studies to solve the above problems, the present inventors have developed an alkali-reduced polyester fiber containing a ceramic antibacterial agent containing magnesia as a main component during the spinning process. It has been discovered that this objective can be achieved by processing, and the present invention has been achieved.

That is, the gist of the present invention is an antibacterial polyester fiber containing a ceramic antibacterial agent containing magnesia as a main component, which is characterized by being subjected to alkali weight loss treatment. It is.

The present invention will be explained in detail below. The present invention shows that, unlike conventional antibacterial zeolite, the ceramic antibacterial agent containing magnesia as its main component loses its original antibacterial function when polyester fibers kneaded with it are subjected to alkali weight loss treatment. This was made based on the discovery of a new fact that could never be considered with conventional zeolite-type antibacterial agents: it is stable without any oxidation, and improves the antibacterial performance of fibers.

[0016] The polyester in the present invention is not particularly limited, but includes polyethylene terephthalate,
Examples include polybutylene terephthalate and copolymers or blends containing these as main components. In addition, substances that are easily eluted by alkaline aqueous solution into polyester,
For example, it is possible to contain an organic sulfonic acid metal salt compound or the like to facilitate the formation of fine irregularities and pores when the fiber is subjected to alkali weight loss processing.

The antibacterial agent used in the present invention is a ceramic-based agent containing magnesia as a main component, and one or more of silica, amphibole, alumina, zeolite, otani stone, or serpentine is appropriately blended with magnesia. (Preferably, the proportion of magnesia is 30% by weight or more.) It is a fired composite ceramic.

[0018] The blending amount of the antibacterial agent is 0.1 to 10% by weight,
A suitable amount is preferably 0.5 to 5% by weight. If this amount is too small, the antibacterial performance will be insufficient, and if it is too large, the thread quality performance will be impaired and it will be economically disadvantageous.

[0019] A small amount of other organic or inorganic antibacterial/deodorizing agent may be used together with the ceramic antibacterial agent containing magnesia as a main component.

[0020] As a method for blending an antibacterial agent into polyester fibers, a masterbatch containing a high concentration of an antibacterial agent is prepared in advance using a twin-screw extruder, etc., and the antibacterial agent is added at an appropriate mixing ratio during spinning. It is possible to adopt a method of blending with a polyester that does not contain the polyester and spinning it, a method of adding an antibacterial agent from the time of polymerization of the polyester, and other known methods.

[0021] The fibers of the present invention include not only fibers spun solely from polyester containing an antibacterial agent, but also polyester containing an antibacterial agent and polyester not containing an antibacterial agent in a core-sheath type or side-by-side type. Composite fibers obtained by composite spinning are also included. Composite fibers can reduce the amount of antibacterial agents, and composite fibers (including hollow composite fibers) whose core is polyester containing antibacterial agents prevent damage to spinning equipment caused by ceramics and improve spinning performance. This is preferable because it improves. Further, it is also possible to prevent damage to the silk-spinning equipment by ceramics by using irregular cross-section fibers having star-shaped protrusions and adding an antibacterial agent only to the center.

[0022] The polyester fiber containing an antibacterial agent is
After being made into a woven, knitted or non-woven fabric, it is subjected to alkali weight loss processing by a known method, and the alkali weight loss rate is preferably 1 to 50% by weight in terms of the balance between antibacterial performance and yarn performance.
More preferably, it is 5 to 35% by weight. If the alkali weight loss rate is less than 1% by weight, the antibacterial performance will not be sufficiently expressed, while if it exceeds 50% by weight, the quality of the yarn will deteriorate, which is not preferable.

[0023] In the alkali weight reduction process, sodium hydroxide is dissolved in a solution of 10 to 100 g per liter of water.
This can be carried out by a standard method of immersion in a bath ratio of 1:50 to 1:200 and treatment at room temperature to boiling for 5 to 60 minutes.

[0024]

[Function] In the present invention, the fact that the antibacterial performance becomes more obvious by applying alkali weight loss processing was something that the inventors could not have predicted.The reason for this is not necessarily clear, but it is as follows. There are several possible mechanisms of action.

That is, by applying the alkali weight reduction process, a large number of fine irregularities and holes are formed on the surface of the polyester fiber. At this time, some of the ceramics blended into the fibers fall off, but since the effect of increasing the surface area is more dominant, the amount of ceramics exposed on the fiber surface increases, resulting in antibacterial performance. It is thought that this will improve.

Furthermore, although the antibacterial performance of conventional antibacterial zeolites is impaired by alkali treatment, it is thought that the antibacterial performance of the antibacterial agent used in the present invention is not impaired by alkali treatment, but is rather activated.

[0027]

[Examples] Next, the present invention will be explained in detail with reference to Examples. Examples 1 to 5 and Comparative Examples 1 to 2 Polyethylene terephthalate with a relative viscosity (measured using an equal weight mixture of phenol and tetrachloroethane as a solvent at a concentration of 0.5 g/dl and a temperature of 20°C) of 1.385 was treated with an antibacterial agent. Magnesia and silica as agents (weight ratio: 60/40
) A master chip kneaded with 20% by weight of composite ceramics is first manufactured, mixed with polyethylene terephthalate chips, melt-spun so that the final ceramic concentration in the fiber is 1% by weight, and then stretched. The raw yarn was obtained.

Next, a tubular knitted fabric was produced using this yarn, and after scouring, it was immersed in a solution of 40 g of sodium hydroxide dissolved in 1 liter of water at a bath ratio of 1/100.
Alkaline treatments were carried out under boiling for different times (10-40 minutes).

[0029] The obtained alkali weight loss processed knitted fabric was subjected to Staph
ylococcus aureus ATCC 653
An antibacterial test was conducted using a bacterial count measurement method using 8p as a test bacterium.

[0030] Similarly, knitted fabrics using antibacterial agent-containing polyester fibers without alkali weight loss treatment (Comparative Example 1) and knitted fabrics using ordinary polyester fibers that do not contain antibacterial agents (Comparative Example 2) were tested in the same manner. An antibacterial test was conducted. The results of the antibacterial test are shown in Table 1.

[0031]

[Table 1]

As is clear from Table 1, the normal polyester fiber (Comparative Example 2: blank sample) had no antibacterial properties at all, whereas Comparative Example 1, in which ceramics were simply kneaded and spun, had some antibacterial properties. Although the effectiveness was recognized, the antibacterial certification standards (lower limit value:
1.6). However, in Examples 1 to 5 in which this was subjected to alkali weight loss processing, a remarkable improvement in antibacterial performance was observed depending on the alkali weight loss rate.

Reference Example 1 The sample obtained in Example 1 was tested according to JIS L-0217-1.
As a result of conducting the same antibacterial test on samples washed 100 times in accordance with 03, logB/, which is an index of antibacterial performance,
C was almost unchanged at 2.8, and the antibacterial performance was maintained.

Reference Example 2 A similar antibacterial test was conducted on the sample obtained in Example 1 by irradiating it with a Sunshine Weather-Ometer for 200 hours, and the results showed that the sample had antibacterial performance at the same level as Example 1. , there was almost no change in the whiteness of the fibers.

[0035]

Effects of the Invention According to the present invention, a white antibacterial polyester fiber that uses a ceramic antibacterial agent containing magnesia as a main component and exhibits excellent antibacterial performance semi-permanently with a relatively small amount added. is provided.

Claims (1)

[Claims] 1. An antibacterial polyester fiber containing a ceramic antibacterial agent containing magnesia as a main component, which is characterized by being subjected to alkali weight loss treatment.