JPH0465510A - Production of antibacterial rayon material - Google Patents

Abstract

PURPOSE:To obtain the subject rayon material suitable for dish-cloth, food- packaging material, fruit-protection bag for cultivation of fruit,filter, backing material for clothes, nonwoven cloth for insole material, clothes, etc., by adding a specific compound such as Mg compound to a solution of a rayon material. CONSTITUTION:The objective rayon material is obtained from a solution produced by adding a compound of Mg, Ca or Zn [e.g. MgO, Ca(OH)2 and ZnSO4] and/or tetrachloroisophthalonitrile to a solution of a rayon material.

Description

[Detailed description of the invention] [Industrial application field]

The present invention is applicable to, for example, cloth towels, food packaging materials, protective bag materials for fruits during fruit cultivation, filters, nonwoven fabrics used as lining materials for clothes and inner materials of shoes, and antibacterial rayon used for clothing, curtains, socks, etc. This method is related to the manufacturing method of the material.

[Background of the invention]

Until now, the amount of rayon used has been steadily decreasing as it has been overtaken by synthetic fibers, but recently, attention has been focused on its hygroscopic properties, and it is used, for example, in dish towels, food packaging, and during fruit cultivation. It is becoming popular as a nonwoven fabric used as protective bag material for fruit, as a filter, as a lining material for clothes, as an inner material for shoes, and as a textile material for clothing, curtains, socks, etc. Incidentally, although attention is being focused on its hygroscopic feature, this property also has the disadvantage of making it easy for mold and bacteria to grow. For this reason, there is a need to develop a rayon material that is resistant to the growth of mold and bacteria.

[Disclosure of the invention]

An object of the present invention is to provide a rayon material that is resistant to the growth of mold and bacteria. The object of the present invention is to provide a method for producing an antibacterial rayon material, which comprises adding a compound selected from the group of Mg, Ca and Zn and/or tetrachloroisophthalonitrile (TPN) to a solution of rayon material. This is achieved by a method for producing an antibacterial rayon material, which is characterized by producing a rayon material from this material. In the above invention, examples of the compound selected from the group of Mg, Ca and Zn include MgO1Cab, Zn
O1Mg(OH)z, Ca(0H)2, Zn(0H)z, Zn5O,, Z
n (CH3Coo)z, ZnC12, ZnC0z,
Examples include Z n (NOx) z. The present invention will be explained in detail below. [Manufacture of alkaline cellulose] Cellulose is alkali cellulose (C6HI.0..NaOH.3) in a caustic soda solution with a concentration of 12.5% to 19%.
A hydrated compound called H20). An example of manufacturing conditions is that after immersing a bulb in 18% NaOH solution, excess caustic soda solution is removed, and finally 100 kg of bulbs are immersed in 18% NaOH solution.
270 kg, that is, until the compression ratio becomes 2.7. The work in the dipping chamber is from this step to the next crushing step. As much as possible of hemicellulose in the bulb? When trying to climb a mountain, lower temperatures are preferable; however, at low temperatures, the number of valves becomes enormous, so the amount of preparation per batch decreases.
It tends to be difficult to squeeze. And if you use a relatively high temperature, what about hemicellulose? There is less climbing involved, and there is less loss due to alkali recovery. A large immersion press is used to produce alkaline cellulose. The amount charged at one time not only determines the size of the immersion press, but also becomes the unit of subsequent operation and becomes the standard for determining the capacity of each machine. The bottom opening/closing method and the front door opening/closing method are generally used to take out the squeeze valve. The feature of the bottom opening/closing type is that when the outlet is opened and retracted, the valve will naturally fall and be discharged, and as the ram retracts, the partition plates will retract and be automatically arranged at a constant pitch. [Crushing process, aging process] The crushing process is a process of crushing the alkali cellulose into small pieces in order to facilitate aging and sulfidation. However, be careful not to crush it excessively. As for the degree of crushing, if 1N is taken in a measuring cylinder, the standard weight should be 180g. Since the power required for crushing shows the highest load at the beginning, supply should be done as gradually as possible, and 30 to 35 horsepower is required for 250 kg. An example of crushing conditions is removal temperature 5 after crushing is completed.
0゛C5 crushing time is 3 hr. This is so-called high-temperature aging, where aging is completed during crushing and no separate aging process is performed, and the reason for the long crushing time is that the aging time is included in this time rather than to ensure a sufficient degree of crushing. It will be done. If it is only for crushing, 1.5 to 2 hours is sufficient. The crusher is commonly called a Zellfather or a Flygoo, and has two Z-shafts for stirring, which are a type of stirrer, and teeth on the saddle-shaped part at the bottom, and crushes by rotating the stirring shafts. be. Approximately 30,001 crushers are used for one batch of 250 kg. When aging a large amount at a constant temperature, it may be divided into several small boxes or aged while stirring. Even if high-temperature aging is carried out, it is preferable that the alkali cellulose, commonly called crumb, has decreased to about 20° C. at the start of sulfurization. [Sulfurization step, dissolution step] When alkali cellulose and carbon disulfide act, industrially, 8245 to 65 moles of C8 are combined with 100 moles of glucose residue. That is, the weight ratio is C3, 23, and 6 to 100 cellulose. The number of moles of C S 2 bonded to 100 moles of cellulose is called the γ value, and is a value representing the degree of sulfidity. A monovalent value of 50 is required immediately after sulfurization. The more the crumb compression is strengthened, the less the volume of the crumb decreases due to sulfurization. The reason for this is thought to be that when the degree of compression is low, the generated xanthate swells and partially dissolves due to the alkali. Therefore, when the crumb is compressed to a large extent, the reaction with C3 tends to proceed uniformly, the amount of by-products is small, and the generated xanthate is easily dissolved. There is a method in which sulfidation is carried out in a churn and dissolution is carried out in a dissolver, which is chemically ideal in that both can be controlled at will, but today it is possible to carry out both reactions simultaneously in one machine. A kneader that performs this process is commonly used. The churn is a drum with a circular or hexagonal cross section and a capacity of 100 kg.
Approximately 2160 for pulp! ! requires a volume of Carbon disulfide is injected in a spray form from a measuring device installed on each machine side through many holes in the central pipe, and the drum is filled with 0.5
Rotates at a speed of rev/min. The dissolver is usually a horizontal or vertical tank with a content of about 14,000 kg per 100 kg of bulb, and two punches are charged into the tank to which calculated amounts of water and concentrated caustic soda solution are added. While the interior is stirred by a propeller, viscose is drawn from the bottom by a gear pump and sent through a grinder to the top where it is circulated. The machine uses a double-walled prine to cool the product and create the appropriate temperature for sending it to the next ripening room. [Aging, filtration, defoaming process] Compared to human silk, spun viscose has a higher content of cellulose and lower NaOH%, and spun viscose has a higher degree of ripening and viscosity than human silk. It's normal. The viscose component provides maximum dispersion of the cellulose particles and therefore targets the highest stability. Alkaline concentration is 5
In the range of ~8%, the higher the alkali concentration, the lower the viscosity and the higher the degree of ripening and stability. At about 8% concentration the viscosity is at a minimum and the stability is at a maximum. That is,
At this concentration, the degree of dispersion of cellulose particles is maximum. As the percentage of cellulose increases, the degree of maturity and stability decrease, and the viscosity increases. From this, 8% cellulose is the highest limit, Na
It is reasonable to consider 6% OH as the minimum limit. However, if the percentage of cellulose is high and the percentage of NaOH is low, main chemicals such as pulp, caustic soda, and sulfuric acid can be saved, and direct production costs will be lower.
, NaOH 5.6 to 5.7%, both of which are often slightly over the limit. However, this tends to cause ripening to proceed more easily and the stability to decrease, so the manufacturing conditions must be strictly adhered to. Care must be taken not to change the temperature, time, etc. of ripening. The high viscosity is due to shortened aging of alkaline cellulose.
The purpose is not to lower the degree of polymerization of cellulose below a certain limit. The reason for increasing the degree of ripening is to provide time for coagulation and decomposition, during which time sufficient tension is applied to the threads, and the aim is to improve the alignment of the micelles. If the viscosity is too high, filtration becomes difficult and defoaming takes a long time, and even if the degree of polymerization is higher than the limit,
It has almost no effect on the strength of the product, so in actual factory practice, the thread-proof viscose viscosity is BF40±2.
It is about 5. If you want something particularly powerful, you may want to increase your BF to 60 or higher. If the degree of viscose maturation is too high, coagulation and decomposition will be too slow;
Even if tension is applied to the yarn, sufficient tension will be produced.On the other hand, if it is too low, there will not be enough time to apply tension, so it must be maintained at an appropriate level.However, the degree of ripening and the components of the spinning bath are correlated. Therefore, both must be maintained at specified values within a certain range. The degree of ripeness is usually 5T14, but if particularly strong is desired, it may be in the range of 20 to 25. Since the degree of ripening is high, there is a limit to shortening the ripening time of Viscose. That is, the time required for filtration and defoaming is the shortest time for ripening, and the higher the viscosity, the longer it takes. It takes about 10 hours to enter the anti-fiber tank, that is, the time to pass through the filter three times and the mixing time, and 18 to 20 hours for defoaming, so the total preparation time is about 35 hours.
becomes. The receiving viscose temperature is 16°C, and the room temperature is 16-1
Maintain a constant temperature within 7°C. To mix the viscose, use a mixer to mix 34 pieces of Nigu. Its main role is to assist in melting and lighten the load on the kneader. Therefore, the mixer has a Jaquent, and while cooling with brine or cold water, 10 to 18
Stir with a stirring blade at rev/min. At the same time, the gear pump pulls out the viscose from the bottom, inserts it through the grinder from the top, and circulates the viscose. Once dissolution, mixing, and temperature control are complete, the liquid is sent to the aging tank. When adding a matting agent, sodium sulfite, etc., it is done in a kneader or mixer. Sodium sulfite has the effect of delaying the ripening of viscose and preventing oxidation, but is generally not used. Titanium oxide, which is a matting agent, can be dispersed uniformly and good results can be obtained by adding it to viscose in the form of slurry with monoball oil in an Ishikawa-type crusher in advance. Often used directly. The purpose of viscose filtration is to remove various impurities.
The influence of undissolved fiber residue on filterability is slight. The substance that causes the most difficulty in filtration is cellulose xanthate, which is highly swollen and dispersed in the form of a gel in viscose. Ordinary xanthate is easily dissolved, but the degree of polymerization is 7.
Cellulose xanthate with a high molecular weight of 0.00 or more tends to cause insoluble gel. Filtration is carried out 3 to 4 times, and the fourth filter press is placed close to the thread-protecting machine and between the thread-protecting tank and the thread-protecting machine. If the fourth filtration is completed completely, it is thought that the candle filter of the thread preventer will be unnecessary. If compressed air is used for filtration, the pressure tends to change and the flow rate of viscose tends to fluctuate, so it is better to use a gear pump. Replace the filter cloth by checking the pressure or filtration rate. The dimensions of the filter press are approximately determined by the dimensions of the filter cloth used, and the standard dimensions are 740 mm x 740 mm, with a total of 51 frames and plates. Pyramid-shaped radiation type plates are the most efficient. Finish the plate and the surrounding area sufficiently smooth to prevent viscose leakage. Since degassing is more effective as the surface area increases, it is convenient to use a slightly tilted tank containing 6.7% Viscose.
Defoaming is performed for 15 to 20 hours at a vacuum degree of 500 to 700 mm. The room temperature was 17° C., and the aging time was 35 hours, half of which was the defoaming time. After mixing, it is necessary to arrange the aging tank and filter press so that the viscose passage in the aging room is the shortest straight path. In particular, the pipe from the thread protection tank to the thread protection machine should be made as short as possible so that viscose does not stagnate in the pipe and always reaches the same flow state. From the thread protection tank to the thread protection machine, Viscose Vibe uses drawn steel pipes, black gas pipes, etc., but since iron sulfide is generated and causes blockage of the thread protection holes, other special materials, such as synthetic materials, are used. Materials made of resin and special glass have been proposed. At least the thread protection tank and thread protection machine should be made of subcontracted copper. Since the viscosity of viscose is extremely high, the pressure loss due to friction is extremely large. Therefore, when viscose is supplied to a thread-protecting machine with a large number of thread-protecting tanks, the pressure varies depending on distance, so the thread-protecting machine is divided into several sections and the liquid is fed from separate tanks. One anti-thread section is approximately 5 to 10 tons per day. Switch to compressed air when starting yarn protection. Air pressure is 7k
g 7cm", but it decreases to 3-4 kg/cm in the viscose tube attached to the thread protection machine. Aging of viscose lowers the viscosity, and by adjusting the degree of ripening, thread protection becomes easier. However, when the degree of polymerization is high, it is unavoidable that the viscosity becomes considerably high.In the first half of ripening, the xanthate groups chemically separate, and the viscosity of the cocolloid decreases due to dehydration. It is generally known that sound waves are effective for dehydration, so applying this to viscose will help lower the viscosity.In other words, the time when the viscosity reaches its minimum can be brought forward by ultrasonic irradiation. By selecting the appropriate solution, it is possible to lower the viscose viscosity and shorten the maturation time without destroying the chain molecules. During spinning, sulfuric acid etc. are usually added, and the solution ranges from an alkaline range to an acidic range. Rayon material is manufactured through such a process, but in order to impart antibacterial properties to rayon material, an antibacterial agent is added to the rayon material solution during the above process. However, even if this technical idea was actually put into practice, it was found that some antibacterial agents did not have antibacterial properties.For example, sodium benzoate, Even with the addition of chemicals such as sodium dehydroacetate, potassium sorbate, thiabendazole, and ortho-phenylphenol, the resulting rayon material had no antibacterial properties. , MgO1CaO1ZnO. Mg(0H)t, Ca(0H)z, Zn(OH)*, Zn5Oa, Zn(CH3Coo)z, ZnCIt, ZnCO5
, a compound selected from the group of Mg, Ca and Zn, such as 'Zn(NOx)t, and an antibacterial agent selected from the group of TPN. Films and threads obtained from rayon solutions containing these antibacterial agents had excellent antibacterial properties.

【Example】

Various chemicals were added between the ripening step and the spinning step (or film forming step) in the same rayon manufacturing process as described above, thereby obtaining a rayon material. The rayon material obtained as described above was subjected to an antibacterial test, and the results are shown in the table. In the antibacterial test, mold and bacteria are dispersed in physiological saline, this dispersion is applied to the culture medium, the above rayon material is placed on the culture medium, the lid is covered, and the incubator is heated at 28°C. After culturing in C for 2 weeks, the growth of mold and bacteria was observed. The bacteria used were Aspergillus niger (A, n), Penicillium citrinum (P, c), Cladosporium cladosporioides (C, c), Trichodermabilitii (T, v), Chaetomium globosum ( C, g), Rhizopus stroniphae (Rs), Escherichia coli (E, C), and urea-degrading bacteria (Pro, ).

Claims (1)

[Claims] A method for producing an antibacterial rayon material, the method comprising adding a compound selected from the group of Mg, Ca and Zn and/or tetrachloroisophthalonitrile to a solution of rayon material,
A method for producing an antibacterial rayon material, the method comprising producing a rayon material from this.