JPH0317952B2 - - Google Patents

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for producing cellulose fibers having a deodorizing function, and more specifically to a method for producing deodorizing fibers in which cellulose fibers are made to support chemically active copper hydroxide. Concerning the manufacturing method. (Conventional technology) Conventionally, high temperature (650° C.
Using a catalyst, a method that burns at a temperature of ~800℃) and decomposes it into odorless and harmless substances such as water vapor and carbon dioxide,
There is a catalytic combustion method that performs oxidation treatment at 250-300℃.
These combustion methods require large-scale equipment and have the disadvantage of being expensive for use in facilities other than industrial facilities that process large amounts of gas. Other relatively cheap and simple methods include adsorbing malodorous substances with adsorbents such as activated carbon and zeolite, and masking methods that eliminate the perception of malodors using aromas that are stronger than the malodor, but these methods are effective against strong odors. Therefore, it is not suitable for deodorizing a wide area. These deodorants are in powder or liquid form, and are stored in a suitable container or impregnated into nonwoven fabric, paper, cloth, etc. before use. However, when placed in a container, there were drawbacks such as a decrease in effectiveness due to a decrease in the contact area with foul-smelling gases, and a decrease in the sustainability of the effect due to weak adhesion to nonwoven fabrics, etc. The present invention relates to a method for producing deodorizing fibers that eliminate the above-mentioned drawbacks by firmly supporting copper hydroxide, which has a high deodorizing effect, on fibers. In the past, an example of focusing on the bactericidal power of copper hydroxide and supporting it on cellulose fibers was published in Japanese Patent Application Laid-Open No. 1973-
No. 160900 is known, but since the purpose is to produce bactericidal fibers, even a small amount of supported copper (9 to 31 mg per 1 g of cellulose fiber in the examples) is effective, but this does not meet the purpose of the present invention. In order for the deodorizing fiber to maintain its effect over a long period of time, it is necessary to carry a large amount of copper. Furthermore, if the strength of the cellulose fibers after carrying copper is reduced, even if deodorizing performance is imparted, practicality will be limited. (Problems to be Solved by the Invention) The present invention is a method for producing deodorizing cellulose fibers, the purpose of which is to carry a large amount of copper hydroxide on cellulose fibers, and to minimize the decrease in strength of the cellulose fibers. . As stated in the above-mentioned Japanese Patent Application Laid-Open No. 160900/1983, copper hydroxide has extremely poor water solubility and is slightly soluble in strong alkalis such as sodium hydroxide, but the amount dissolved in 4N hydroxide is It is 850ppm in sodium aqueous solution. In order to prevent a decrease in the strength of cellulose, it is said that an aqueous solution of sodium hydroxide with a concentration of 4N or higher is not preferable. However, in the present invention, it is desired to strongly prevent a decrease in the strength of cellulose fibers, and the cellulose fibers used can be freely changed in fiber form such as fiber length and denier, and can be easily processed appropriately according to the desired product. Therefore, regenerated cellulose is a preferred material. For this reason, it was necessary to set the alkali concentration within a range in which the strength of the regenerated cellulose fibers is relatively small. Under such conditions, the present inventors succeeded in supporting a large amount of copper hydroxide on cellulose fibers. (Means for Solving the Problems) The present inventors previously filed an application for a method for using copper hydroxide or copper oxide to support a large amount of copper hydroxide on cellulose fibers for the same purpose as the present invention ( As a result of continued research in Japanese Patent Application No. 61-78830, it was discovered that copper hydroxide could be supported on cellulose fibers even when basic copper carbonate was used. Basic copper carbonate is a mixture of copper hydroxide and copper carbonate, and is known in nature as pythonite.
Its composition is not constant, and there are several types according to the literature.
It is written as CuCO ₃・Cu (OH) ₂ , CuCO ₃・3Cu (OH ₂ ), etc. In this specification, it is expressed as _CuCO3.nCu (OH) ₂ . The reaction formula for basic copper carbonate to dissolve in an aqueous sodium hydroxide solution is CuCO ₃・nC(OH) ₂ +2(n+2)NaOH → (n+1)[Cu(OH) ^2- ₄・2Na, assuming that sodium hydroxide is in large excess. ⁺ ]+Na ²⁺ ₂
・It is thought to be CO ^2- ₃ , and its reaction with cellulose is thought to be the same as the cellulose-copper coordination reaction using copper hydroxide. The present invention involves mixing and dispersing basic copper carbonate powder in a 0.5 to 2.5 N aqueous sodium hydroxide solution or potassium hydroxide aqueous solution at a ratio of 0.5 to 50 g/distance, and immersing cellulose fibers in this mixed dispersion to form a base. This method for producing deodorizing cellulose fibers is characterized in that a copper hydroxide ion complex is chemically bonded to cellulose molecules by adsorbing powdered copper carbonate onto cellulose fibers. It is desirable that the cellulose fibers used be pretreated with an aqueous alkaline solution to allow the aqueous alkaline solution to sufficiently penetrate into the fibers. For example, if natural cellulose fibers are immersed in a 0.5N sodium hydroxide aqueous solution at 60°C for 0.5 to 1.0 hours, the cellulose fibers will swell sufficiently, the fats and oils attached will be removed, and copper hydroxide will easily react with the cellulose molecules. Become. In addition, when using regenerated cellulose fibers, since sulfides tend to adhere to regenerated cellulose fibers during the spinning process, adding a small amount of cupric hydroxide to the alkaline pretreatment solution will remove sulfides from copper sulfide. It can be precipitated and removed as As the aqueous alkaline solution for dispersing basic copper carbonate, an aqueous solution of sodium hydroxide or potassium hydroxide is used, and its concentration must be 2.5 or less so as not to excessively decompose cellulose fibers.
Also, if the temperature is too low, the decomposition of basic copper carbonate will not proceed,
Since a sufficient amount of copper hydroxide ion complex cannot be supplied, at least 0.5 normality is required. If the amount of basic copper carbonate is more than 50 g, it will not be uniformly dispersed in the alkaline aqueous solution and will not adhere to the cellulose fibers, resulting in a wasteful amount. Also 0.5
If the amount is less than 1 g/g, the amount of powdery substances adhering to the cellulose fibers will not be sufficient, and in order to bond a large amount of copper hydroxide ion complex to the cellulose fibers,
This is not preferable because it requires a long reaction time. Basic copper carbonate becomes sticky particles in such an alkaline aqueous solution to form a suspension, and when cellulose fibers are introduced into the suspension, the sticky particles coagulate and adhere around the cellulose fibers. Copper ion complexes are formed on the surface of cellulose fibers from this attached basic copper carbonate.
Cu(OH) ₄ is supplied and seems to be chemically bonded to the cellulose fibers as follows. After the copper ion complex has fully bonded to the cellulose fibers, in order to remove excess basic copper carbonate particles,
Squeeze out the whole thing and leave it in the water. At this time, the higher the water temperature, the lower the adhesion of the particles, and if the water temperature is 50°C or higher, they will fall off almost completely in about 10 minutes. For water extraction, use a centrifugal dehydrator to thoroughly remove the alkaline aqueous solution. Cellulose fibers still absorb alkaline aqueous solutions even after watering, and even if they are left in water, the PH value around the fibers remains alkaline, but if the bath ratio is set to 1:50 or higher,
If the water is gently stirred, the basic copper carbonate particles will easily fall off. (Action of the invention) The method of the present invention supports the copper ion complex on the cellulose fibers, and the supporting reaction is faster than the previously applied method using copper hydroxide or copper oxide (Japanese patent application No. 61-78830). It's also expensive. Copper ion complexes bonded to cellulose fibers cause chemical reactions with ammonia molecules, sulfur ions, and acidic groups, which are the sources of malodorous substances, and decompose malodorous substances that contain these substances, such as ammonia, hydrogen sulfide, sulfur oxides, formalin, etc. It has a deodorizing effect. (Example) (1) 250g of 5 denier viscose rayon cotton was pretreated and 1g of cupric hydroxide was added.
It was immersed in a 0.5N aqueous sodium hydroxide solution at 5°C. One hour later, this rayon cotton was hand-wrung, and the same treatment was repeated once more, followed by centrifugal dehydration to obtain scouring cotton containing an aqueous sodium hydroxide solution. Next, 250 g of this scoured rayon cotton was dispersed little by little into a 1.5N aqueous sodium hydroxide solution 5 along with 75 g of basic copper carbonate, and the mixture was allowed to stand at room temperature. The rayon cotton gradually turns blue, and after 24 hours, it is dehydrated, washed with water, and heated at 80℃ for 3 days.
The copper content of the obtained blue rayon cotton, which was dried for an hour, was 12.4%. (2) 250g of scouring cotton obtained in the same manner as in Example 1
and 75 g of basic copper carbonate were added to a 1.0N aqueous sodium hydroxide solution 5 while being dispersed little by little, and the mixture was allowed to stand at room temperature. The rayon cotton gradually turns blue, and after 24 hours, it is dehydrated and washed with water.
It was dried at ℃ for 3 hours. The copper content of the obtained blue rayon cotton was 5.8%. (3) 250g of scouring cotton obtained in the same manner as in Example 1
was dispersed little by little in a 0.5 N aqueous sodium hydroxide solution 5 with 75 g of basic copper carbonate, left at room temperature for 24 hours, dehydrated, washed with water, and heated to 80°C for 3 hours.
Dry for an hour. The copper content of the obtained blue rayon cotton was 3.7%. (4) 250g of scouring cotton obtained in the same manner as in Example 1
was dispersed little by little in a 2.5 N aqueous sodium hydroxide solution 5 together with 75 g of basic copper carbonate, left to stand at room temperature for 10 hours, dehydrated, washed with water, and dried at 80° C. for 3 hours. The copper content of the obtained blue rayon cotton was 17.0%. (5) In Example 1, before dehydrating the blue-dyed rayon, take a part of it and squeeze it by hand.
Immerse in specified sodium hydroxide aqueous solution at 60℃
It was heated for 6 hours. The copper content of the blue rayon cotton after washing and drying was 12.8%. (6) Blue rayon cotton was obtained in exactly the same manner as in Example 1 except that the sodium hydroxide aqueous solution was replaced with a potassium hydroxide aqueous solution. The copper content was 11.9%. (Effect of the invention) Copper hydroxide-supported rayon cotton obtained in Example 1
As shown in Figure 1, loosely pack 0.3 g into a glass tube 1 with an inner diameter of 100 mm, and insert it through a rubber stopper 2.
ml was fixed at the mouth of flask 3. A small amount of a foul-smelling gas generating substance 4 is placed in the flask 3 in advance, and the bottom of the flask 3 is heated or a gas is generated through a chemical reaction and the gas is introduced into the glass tube 1 using copper hydroxide-supported rayon. It was brought into contact with cotton 5. Several types of foul-smelling gas generating substances (shown in Table 1)
After each gas was generated, the odor was smelled at the outlet of the glass tube, but no odor peculiar to malodorous substances was detected. For aldehydes, rayon cotton 5 was pre-wetted with a 0.2N aqueous sodium hydroxide solution. 【table】

[Brief explanation of the drawing]

The drawing is a front view of an instrument for confirming the effects of the present invention. In the figure, 1...Glass tube, 2...Rubber stopper,
3...Flask, 4...Offensive gas generating substance, 5
... Rayon cotton carrying copper hydroxide.

Claims (1)

[Claims] 1 Add basic copper carbonate powder to a 0.5-2.5N aqueous sodium hydroxide solution or aqueous potassium hydroxide solution.
The copper hydroxide ion complex is chemically bonded to the cellulose molecules by mixing and dispersing it at a ratio of 0.5 to 50 g/distance and immersing the cellulose fibers in this mixed dispersion to adsorb the basic copper carbonate powder onto the cellulose fibers. A method for producing deodorizing cellulose fiber, characterized by: