JPH0123589B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricant for polyurethane elastic fibers.More specifically, the present invention relates to a lubricant for polyurethane elastic fibers. This invention relates to an oil agent for obtaining small polyurethane elastic fibers. Polyurethane elastic fibers have a lower Young's modulus than other clothing fibers and are extremely stretchable, so frictional resistance with guides and the like during post-processing steps such as warping and knitting must be particularly small. In addition, since the threads are highly adhesive, unless an oil agent with anti-adhesive properties is applied, the threads will stick to each other on the cheese, resulting in poor unwinding properties, resulting in frequent thread breakage in the post-processing process. There is. Therefore, it is important to reduce the frictional resistance of the yarn (improve the so-called smoothness) and further improve the unwinding property.For this reason, polyurethane elastic fibers require a considerably larger amount of oil agent than other synthetic fibers. is usually attached during the spinning process. Especially in recent years, polyurethane elastic fibers
Since the vehicle is used at high speeds of 400 to 800 m/min, there is a demand for particularly low frictional resistance during high-speed running. However, when the oil adhesion rate is high, oil and scum (oligomers in the yarn extracted by oil components and solid or high viscosity components in the oil are solid or paste-like) on the guides and knitting needles of the knitting machine that the yarn comes into contact with. (separated)
Since a large amount of lint adheres thereto, there are drawbacks such as staining of the product and clogging due to adsorption of fluff, resulting in the need for frequent cleaning. It also has the disadvantage of causing oil to seep out from the cheese or beam, contaminating equipment, machinery, etc. Conventionally, in order to reduce the stickiness and frictional resistance of threads, talc was used as a smoothing agent, mineral oil was used as the main agent, and various higher fatty acid esters, ethylene oxide adducts of higher alcohols, ethylene oxide adducts of higher fatty acids, Attempts have been made to use compounded oils containing metal soaps, modified silicones, and the like. However, these methods do not provide sufficient anti-adhesive effects, and the smoothing agent causes serious wear on spinning machines, warping machines, knitting machines, etc., and scum is generated during the warping and knitting processes. However, it has drawbacks such as thread breakage and deterioration of product quality. In view of the current situation, the present inventors have conducted extensive research to develop an oil agent for polyurethane elastic fibers that exhibits excellent effects with a small amount of oil adhesion rate, and have finally arrived at the present invention. That is, the present invention operates at 25°C.
Contains diorganopolysiloxane (A) with a viscosity of 100 centistokes or less and diorganopolysiloxane (B) with a viscosity of 5,000 to 15,000 centistokes as essential components, and the blending ratio of both components is (A): ( B)=85-95:15-5, and the total blending amount of both components is 40% by weight or more based on the total oil component. Hereinafter, the oil agent of the present invention will be explained in more detail. The oil agent of the present invention contains the following two types of diorganopolysiloxanes in specific proportions as main active ingredients. (A) Diorganopolysiloxane with a viscosity (25℃) of 100 centistokes or less (B) Diorganopolysiloxane with a viscosity (25℃) of 5,000 to 15,000 centistokes Dimethylpolysiloxane is usually used as the diorganopolysiloxane. A part of the methyl group may be substituted with another monovalent organic group such as an alkyl group, a phenyl group, an aminoalkyl group, a vinyl group, or an epoxy-containing group. It may also be a polysiloxane having a hydroxyl group, an alkoxyl group, etc. at the end. Furthermore, a small proportion of the methyl groups may be replaced by hydrogen. The mixing ratio of diorganopolysiloxane (A) and (B) is (A):(B)=85-95:15-5 by weight. If the proportion of diorganopolysiloxane (B) exceeds the above range, the viscosity of the oil increases and it becomes difficult to apply it uniformly. On the other hand, if it is too small, the coefficient of static friction increases, resulting in the disadvantage that the threads on the surface of the cheese lose their slimy feel and the smoothness of the fibers decreases. Since the diorganopolysiloxanes (A) and (B) in the present invention differ only in molecular weight and are structurally identical or similar, a major feature is that they can be mixed in any ratio. That is, when diorganopolysiloxane (A) is used in combination with polyether-modified silicone, which is normally used for polyurethane fibers, the compatibility between the two is poor, and an appropriate medium, ie, binder oil, is required to form a uniform oil agent. . However, most of the binder oils are organic solvents, which tend to elute oligomers from the fibers, which not only causes scum generation, but also has the drawback of promoting coloration of the fibers due to nitrogen oxide gas in some cases. In the present invention, it is not necessary to use a binder oil, and by changing the mixing ratio, the viscosity and smoothness of the oil can be freely changed, and the drawbacks caused by the use of a binder oil can also be solved. Next, the effects of each active ingredient in the oil of the present invention will be explained. Diorganopolysiloxane (A) is particularly effective for smoothness at high speeds, that is, it exhibits excellent smoothness (low frictional resistance) when the thread travels at high speeds of 200 m/min or higher. The smoothing effect of this material does not change much depending on the viscosity as long as the viscosity is 100 centistokes or less. However, particularly preferred is between 3 and 50 centistokes. On the other hand, diorganopolysiloxane (B) has a large frictional resistance when the thread runs at high speed, but on the contrary, it has an excellent effect against low-speed friction when the thread runs at a low speed. These diorganopolysiloxanes are not compatible with the oligomers in the yarn regardless of their viscosity, and they are also poorly compatible with various additives. The amount of scum produced can be significantly suppressed. Normally, the running speed of the yarn in the post-processing processes of polyurethane elastic fibers, such as knitting, warping, rewinding, etc., is as low as about 1 m/min.
There are cases where the speed is over 400m/min, and there is an extremely wide variety. However, the smoothness of a yarn is speed dependent, and a yarn that is smooth at low speeds does not necessarily have good smoothness at high speeds. Therefore, it is desirable that the oil applied to the polyurethane elastic thread have the ability to improve smoothness at all speeds from low to high speeds. The diorganopolysiloxane (A) used in the present invention has the ability to improve smoothness at high speed, while the diorganopolysiloxane (B) has the ability to improve smoothness at low speed. By changing this, we succeeded in reducing frictional resistance over a wide range of running speeds. In order to adjust the viscosity of the oil to a value that is convenient for oiling and can be uniformly applied, usually 50 centistokes or less, the viscosity and blending ratio of the ingredients are adjusted within the above ranges. Furthermore, diluents and antistatic agents can be added as appropriate to adjust viscosity and adhesion, but the total amount of diorganopolysiloxane (A) and (B) is usually 40% by weight based on the total amount of oil. or more, preferably 50% by weight or more. Examples of diluents that can be used include mineral oil (preferably viscosity (25°C) of 60 seconds or less), aliphatic alcohols having 12 or more carbon atoms, saturated fatty acids having 2 or more carbon atoms, and saturated aliphatic fatty acids having 1 or more carbon atoms. Ester with 12 or more carbon atoms obtained from alcohol, 7-20 carbon atoms
Examples include esters of mono- to trivalent aromatic carboxylic acids and saturated aliphatic alcohols having 1 or more carbon atoms, ethers or polyethers having 12 or more carbon atoms (the number of ether bonds is 6 or less). Furthermore, a fluoro compound in which the hydrogen atom of the alkyl group in the aliphatic alcohol or fatty acid is replaced with a fluorine atom can also be used. It is also possible to incorporate polyether-modified silicones as part of the diorganopolysiloxane (B) or as part of additional ingredients. The present invention will be explained below with reference to Examples. In addition,
Parts and percentages in the examples are by weight unless otherwise specified. Moreover, the unwinding property in the examples is the minimum elongation rate required to stably wind up the threads in the innermost layer of cheese using a drive roller and a winding roller. Smoothness (A) was measured by radar method. However, the friction body is made of chrome-plated metal, and its surface speed during rotation is
It is 0.9m/min. The load applied to the measurement sample is thread 1
The actual weight is 0.1g. Smoothness (B) can be evaluated by the coefficient of friction of the yarn against the friction surface of the knitting needle. The measurement was carried out using Keikiki Kogyo Co., Ltd. F-Meter R-1182.
The measurement principle is as follows. That is, thread is threaded around a knitting needle at a friction angle α, the thread is run in one direction, the thread tension is measured before and after passing through the knitting needle, and the coefficient of friction is calculated from this using the following equation. Note that the speed can be changed from 0m/min to 500m/min. f = 1/α (lnt ₁ - lnt ₂ ) t ₂ = Yarn tension on the input side (g) t ₁ = Yarn tension on the output side (g) α = Friction angle in radians ln = Natural logarithm f = Friction coefficient The Scum Test is evaluated by the following method.
When a razor blade was applied to the thread that was being unwound at 10 m/min and wound up to 30 m/min, the amount of white sticky substance adhering to the razor was visually determined. Example 1 Methylenebis(4-phenyl isocyanate)
10 parts of polytetramethylene glycol having a molecular weight of 1500 were reacted at 80°C for 60 minutes to obtain a prepolymer, which was dissolved in 90 parts of dimethylformamide, and then dissolved in 30 parts of dimethylformamide while maintaining the temperature at 0°C. , 1.4 parts of 2-propylene diamine. The obtained viscous polymer solution (viscosity 1200 poise at 20°C) was spun into an air stream heated to 250°C through a spinneret with a pore diameter of 0.15 mm and 30 holes, and the formed thread was After converging by mechanical false twisting when the concentration reached 1%, an oil agent was applied and the cheese was rolled at 200 m/min to obtain cheese weighing 500 g. Table 1 shows the results of examining the quality of polyurethane elastic yarns and cheeses obtained with various oil compositions. As is clear from the table, when the oil of the present invention was used, it showed sufficient effects (excellent unwinding properties and smoothness) even at a low oil adhesion rate, and there was no scum generation or oil leaching. The comparative examples using oil agents did not show good results in all respects. 【table】

Claims (1)

[Claims] 1 Diorganopolysiloxane (A) with a viscosity of 100 centistokes or less at 25°C and 5000 ~
Contains 15,000 centistokes diorganopolysiloxane (B) as an essential component, the weight ratio of both components is (A):(B)=85-95:15-5, and the total of both components An oil agent for polyurethane elastic fibers, characterized in that the blending amount is 40% by weight or more based on the total oil component.