TWI809093B - Tubular package containing polylactic acid monofilament - Google Patents

Abstract

A cylindrical package containing polylactic acid monofilaments, the polylactic acid monofilaments are composed of lactic acid monomers at least 50% by weight. Each value of the end surface hardness measured at the place is in the range of 35~70.

The present invention provides a cylindrical package containing polylactic acid-based monofilaments that is excellent in yarn fabric quality and high-passability during weaving, and unwound at a high speed.

Description

Tubular package containing polylactic acid monofilament

The present invention relates to a cylindrical package comprising polylactic acid-based monofilaments. More specifically, it is a tubular package containing polylactic acid monofilament that can obtain excellent yarn fabric quality, excellent high-pass property during warping and weaving, and can also respond to increased weaving speed .

As environmental issues such as prevention of global warming, conservation of fossil resources, and reduction of waste are widely mentioned, biodegradable polymer systems using biomass are attracting attention. As such biodegradable polymers, polylactic acid polymer systems special attention. Polylactic acid polymer is a polymer made of lactic acid obtained by fermenting starch extracted from plants as a raw material. Among biodegradable polymers utilizing biomass, it has a balance of transparency, mechanical properties, heat resistance, and cost. most excellent. Generally speaking, the manufacturing method of polylactic acid monofilament has the two-step method of temporarily winding up the unstretched filament, and then stretching (Patent Document 1); or the one-step method of directly stretching and winding after melting the polymer ( Patent Document 2, Patent Document 3), but from the point of view of the production cost of the polylactic acid monofilament, the 1-step method is superior to the 2-step method. In Patent Document 2, it is proposed that there is no yarn drop on the end surface of the polylactic acid monofilament package, and it is proposed to control the stretching tension at 0.04cN/dtex~0.35cN/dtex, and control the winding tension at 0.04cN/dtex~0.20cN /dtex manufacturing method. In addition, Patent Document 3 proposes a polylactic acid monofilament package that prevents yarn loss at the end face of the package, suppresses dry heat shrinkage stress at the innermost layer of the package, and improves the unwinding property of the innermost layer.

[Prior Art Literature] [Patent Document]

Patent Document 1: Japanese Patent Laid-Open No. 2001-131826

Patent Document 2: Japanese Patent Laid-Open No. 2013-32223

Patent Document 3: International Publication No. 2016/194578

However, in recent years, for the purpose of improving the productivity of the weaving process, the weaving speed has been increased, and polylactic acid-based monofilament packages with good high-speed unwinding properties have been strongly demanded.

The tubular package of polylactic acid monofilament described in Patent Document 3 suppresses fluctuations in unwinding tension when unwinding the monofilament from the package during warping and weaving, and suppresses dry heat in the innermost layer of the package. Shrinkage stress improves the unwinding performance of the innermost layer, but as the weaving speed increases, when the yarn is unwound from the package, the phenomenon of unwinding in the shape of a wheel occurs, which is the so-called stripping, and severe stripping , The loom stops, the high passability deteriorates, and when the loop is slightly off, the quality of the yarn fabric deteriorates due to the weaving without stopping the loom. In the cylindrical package of polylactic acid monofilament described in Patent Document 2, similarly, as the weaving speed increases, loop stripping tends to occur, resulting in problems of high passability and deterioration of yarn fabric quality.

The object of the present invention is to overcome the problems of the aforementioned prior art, and provide a tubular package comprising polylactic acid monofilaments, which can obtain excellent yarn fabric quality, excellent high-pass performance during weaving, and high-speed unwinding for good.

In order to achieve the above-mentioned problems, the present invention adopts the following configurations. Right now,

(1) A tubular package containing polylactic acid-based monofilaments, which is a cylindrical package containing more than 50% by weight of polylactic acid-based monofilaments composed of lactic acid monomers, characterized in that: For the part with a thickness of 25mm, each value of the hardness of the end surface measured at 36 places at intervals of 10° is in the range of 35 to 70.

(2) The cylindrical package containing polylactic acid monofilament as described in (1), characterized in that: the CV value (variation Coefficient, %) is 15% or less.

According to the present invention, it is possible to provide a polylactic acid-based monofilament tubular package capable of obtaining excellent yarn fabric quality, excellent high passability during weaving, and good high-speed unwinding properties.

1‧‧‧Silk

2‧‧‧paper tube

3‧‧‧polylactic acid monofilament package

4‧‧‧Spinning section

5‧‧‧Spinning nozzle

6‧‧‧Oil supply device

7‧‧‧1st Godet Roller (U)

8‧‧‧1st Godet Roller (L)

9‧‧‧2nd Godet Roller (U)

10‧‧‧2nd Godet Roller (L)

11‧‧‧Transverse device

12‧‧‧Roller ring

13‧‧‧Coiling side spindle

14‧‧‧Standby side spindle

15‧‧‧Coiling device

Fig. 1 is a schematic front view of a cylindrical package of polylactic acid monofilament according to the present invention.

Fig. 2 is a schematic diagram of an example of a spinning device for producing a cylindrical package of polylactic acid-based monofilament according to the present invention.

Fig. 3 is a schematic front view for explaining the method of measuring hardness implemented in the present invention.

Fig. 4 is a schematic side view for explaining the method of measuring hardness implemented in the present invention.

[Mode of Implementing the Invention]

The polylactic acid-based polymer used in the present invention is a polymer having -(O-CHCH ₃ -CO)- as a repeating unit, which refers to polymerizing oligomers of lactic acid such as lactic acid or lactide. In lactic acid, there are two types of optical isomers of D-lactic acid and L-lactic acid, and its polymers also include poly(D-lactic acid) composed of only D-body and poly(D-lactic acid) composed of only L-body. (L-lactic acid), and the polylactic acid polymer composed of the two. As the optical purity of D-lactic acid or L-lactic acid in the polylactic acid polymer becomes lower, the crystallinity decreases and the melting point drops larger. Therefore, in order to improve heat resistance, the optical purity is preferably 90% or more. However, unlike the above-mentioned system in which the two types of optical isomers are simply mixed, after the above-mentioned two types of optical isomers are blended and formed into fibers, if a high-temperature heat treatment of 140°C or higher is applied to make it into a formed Stereocomplexes with racemic crystallization are more preferred because they can remarkably increase the melting point.

In the present invention, the polylactic acid-based monofilament must have a ratio of lactic acid monomers constituting the polymer to 50% by weight or more from the viewpoint of preservation of fossil resources and bio-recycle. The lactic acid monomer constituting the polymer is preferably at least 75% by weight, more preferably at least 95% by weight. Moreover, as long as the properties of the polylactic acid within this range are not impaired, components other than lactic acid may be copolymerized.

In the cylindrical package of the present invention, each value of the end surface hardness (hereinafter referred to as package end surface hardness) measured at 36 positions at intervals of 10° at the portion of the package with a thickness of 25 mm must be in the range of 35 to 70. The so-called end surface hardness of the package here refers to the hardness of the 25mm thick part of the package when pushing the C-type needle of the Asker rubber hardness tester (according to JIS K7312: 1996). Next, the measurement was performed at 36 locations while shifting the measurement positions by 10° in the circumferential direction of the package, and the hardness was read for each. By setting the hardness of the end surface of the package in the range of 35 to 70, even at high-speed unwinding, the defect of loop stripping can be suppressed, excellent yarn fabric quality can be obtained, and a package with excellent high passability can be obtained. If the package hardness is less than 35, the thread will fall due to the friction between the end surface thread and the unwinding thread during high-speed unwinding, and the ring-shaped unwinding defect of looping will occur, and the quality of the yarn fabric will tend to deteriorate. If the hardness of the end surface of the package exceeds 70, the swelling of the end surface of the package (hereinafter referred to as protrusion) becomes large, so the high-speed unwinding property tends to deteriorate. The hardness of the end surface of the package is preferably 50~65.

In the cylindrical package of the present invention, the CV value (%) of the hardness of the package end surface measured at 36 positions at intervals of 10° at a portion of the package with a thickness of 25 mm is preferably 15% or less. By making the CV value (%) of the package end surface hardness less than 15%, the collapse of the yarn layer due to the influence of the residual stress of the polylactic acid monofilament remaining in the wound package can be suppressed. In addition, since the collapse of the yarn layer due to the vibration generated during the deceleration of the spindle can also be suppressed, there will be no loop stripping during high-speed unwinding, and the high-pass performance and yarn fabric quality are good. The CV value (%) of the hardness of the end surface of the package is more preferably 10% or less.

As a method of controlling the hardness of the package end surface and the CV value (%) of the package end surface hardness within this range, by adjusting the winding tension, surface pressure, traverse (traverse) oscillation range, and decelerating the winding spindle It is possible to combine a series of winding conditions of speed as a whole.

First, the winding tension must be 0.10cN/dtex or less. By making the take-up tension 0.10cN/dtex or less, residual stress can be reduced and protrusion can be suppressed. If the winding tension exceeds 0.10cN/dtex, the protrusion will become larger due to the influence of residual stress, and the hardness of the package end surface of the protrusion will decrease. Moreover, since the hardness of the package end surface as a whole becomes high, variations in the hardness of the package end surface tend to occur. If the take-up tension is lower than 0.04cN/dtex, the thread will rewind and break on the godet roll, so it is preferably 0.05~0.08cN/dtex.

Second, the load (hereinafter referred to as surface pressure) relative to the wire length of the roller ring (12 in Fig. 2) contacting the package (3 in Fig. 2) must be 125 N/m or less. By making the surface pressure 125N/m or less, it is possible to form a package while suppressing the collapse of the yarn layer. Also, since the residual stress can also be reduced, variation in the hardness of the package end surface can be suppressed. If the surface pressure exceeds 125 N/m, the yarn layer collapse will easily occur, and since the package end surface hardness of the portion where the yarn layer collapses will decrease, the package end surface hardness variation will easily occur. If the surface pressure is lower than 50N/m, the hardness of the end surface of the package will become too low, so the collapse of the thread layer will easily occur. Since the hardness of the end surface of the package at the part where the thread layer collapses will further decrease, the end surface of the package will easily occur. hardness deviation. Preferably it is 80~120N/m.

Thirdly, it is preferable to make the traversing swing range of the traversing device (11 in FIG. 2) be in the range of 3 to 5%. By making the traverse vibration range 3~5%, it is possible to suppress the overlapping of the filaments forming the package, and suppress the vibration caused by the coiling device (15 in Fig. 2), or the polylactic acid monofilament package (Fig. 2 3) The collapse of the silk layer caused by the vibration between the specified volume and the stop of the spindle. There is no particular limitation on the rocking cycle of the traverse, but it is preferably a cycle of 3 seconds to 4 seconds. As for the traverse method, there are 1-axis to 3-axis blade traverse methods, micro-cam traverse methods, and spindle methods that can shorten the free length (free length), etc., and are not particularly limited. In view of the stability of package formation, the micro-cam traverse method with good yarn gripping property is preferable. When the traversing vibration range is less than 3%, the yarn layer is likely to collapse due to the overlap of the filaments forming the package, and the hardness of the package end surface of the collapsed part of the yarn layer will decrease, so it is easy to occur the hardness deviation of the package end surface. If the traversing vibration range exceeds 5%, yarn falling to the end surface of the package will easily occur, so the quality of the fabric will deteriorate due to fluctuations in the unwinding tension during warping and weaving.

Fourth, it is preferable to set the deceleration speed for decelerating the spindle to 20~70m/sec after the polylactic acid monofilament package (Fig. 2-3) reaches the specified volume. By setting the deceleration speed for decelerating the spindle to 20~70m/sec, it is possible to suppress the collapse of the yarn layer due to the vibration etc. generated during the deceleration of the spindle. If the deceleration speed of the spindle deceleration exceeds 70m/sec, the yarn layer collapses easily due to the vibration generated during the deceleration of the spindle, and the hardness of the package end surface of the part where the yarn layer collapses will decrease, so it becomes Hardness variation of the end surface of the package is easy to occur. The slower the speed at which the spindle is decelerated, the more the collapse of the yarn layer of the package can be suppressed, but the workability will deteriorate because the time until the spindle stops becomes longer. More preferably, it is 20-40 m/sec, and it is still more preferable that it is 25-30 m/sec.

In this way, by combining elements of the above-mentioned first to fourth winding methods, it is possible to suppress the hardness of the end surface of the package.

Since the package form affects the unwinding of the yarn in the next step, a good package form is required. Referring to the schematic diagram of the cylindrical package in Fig. 1, it will be described in detail below. First of all, in the package form, as a problem other than thread drop, there is a difference (B-C) expressed by the end winding diameter B in the thickness direction of the package and the minimum winding diameter C in the thickness direction of the package. Saddle (saddle) (edge erected), the smaller the saddle, the better the unwinding of the yarn at high speed. The unwinding speed required in the next step also reaches 1000~1200m/min, but if the saddle is high, the surface of the polylactic acid fiber with low wear resistance will be scraped because the saddle part is continuously brushed by the unwinding filament , In the end face cycle of the package (equivalent to the length of the wire from the saddle to the other side of the saddle), there is a consistent defect. Also, since the unwinding tension of the yarn tends to fluctuate in the saddle portion, it becomes a factor of instability in the next step. Therefore, in order to suppress the end surface periodic defect in the next step and perform stable high-speed unwinding, the saddle portion (B-C) is preferably 6 mm or less, more preferably 4 mm or less, further preferably 2 mm or less. Also, although the lower limit is not particularly specified, it is ideally 0 mm.

Also, there is a protrusion (protrusion) represented by ((maximum package width E-package width D)/package width D)×100, the smaller it is, the better the unwinding performance of the yarn at high speed excellent. When the protrusion is high, the yarn contacts the protrusion during unwinding, and the yarn layer collapse is likely to occur. Therefore, in order to suppress the end face periodic defect in the next step and perform stable high-speed unwinding, the overhang is preferably 10% or less, more preferably 7% or less, further preferably 5% or less. Also, although the lower limit is not particularly specified, it is ideally 0%.

The polylactic acid-based monofilament constituting the cylindrical package of the present invention preferably has a tensile strength of 2.5 cN/dtex or higher. By being 2.5 cN/dtex or more, it is possible to suppress yarn breakage when the polylactic acid-based monofilament is unwound from a package during weaving, and when it is made into a yarn fabric, good fabric strength can be obtained. More preferably, it is more than 3.5 cN/dtex. The higher the strength, the better, but the maximum strength in the present invention is 4.3cN/dtex. In addition, the strength is stretched by the speed difference between the heated first godet roll and the heated second godet roll to obtain a specified strength.

The elongation of the polylactic acid monofilament constituting the cylindrical package of the present invention is preferably 35%~55%. By being in such a range, the high passability at the time of weaving and the high processing stability of the yarn fabric for tea bags are improved. A further preferred elongation is 35%~45%. The elongation is stretched by the speed difference between the heated first godet roll and the heated second godet roll to obtain the specified elongation.

The fineness of the polylactic acid monofilament constituting the cylindrical package of the present invention is preferably 15 dtex to 40 dtex. With such a range, when used as a yarn fabric for tea bags, the most suitable open area per unit area can be obtained, the most suitable extraction speed of tea can be obtained, and tea with flavor can be obtained.

The boiling water shrinkage of the polylactic acid-based monofilament constituting the cylindrical package of the present invention is preferably 20% or less. By making it less than 20%, when processed into tea bag yarn fabric, even if shrinkage occurs when hot water is injected, it can become the most suitable open area per unit area, and become the most suitable extraction speed for tea, becoming Flavored tea. More preferably below 17%.

Next, an example of the manufacturing method of the polylactic acid monofilament package of the present invention will be described based on the schematic diagram of the steps in FIG. 2 . Fig. 2 is a schematic view showing steps of an example of a method for manufacturing a polylactic acid monofilament package of the present invention.

The spinning block (spinning block) 4 in the melt spinning machine is heated by heating means not shown. The spinning nozzle 5 is installed in the aforementioned spinning section 4, the polylactic acid polymer is melted, and the polymer is discharged from the spinning nozzle 5 to form a filament 1. In the cooling device shown, after the thread 1 is uniformly cooled, the oil agent is applied to the thread 1 by the oil supply device 6, and after stretching between the first godet rollers 7, 8 and the second godet rollers 9, 10, The yarn is wound up by the winding device 15 while being traversed by the micro-cam traversing device 11 to form the package 3 . When the package 3 reaches the prescribed winding volume, the winding-side spindle 13 and the standby-side spindle 14 perform a turret, and the yarn is automatically switched to the standby-side spindle 14 . The package 3 series on the standby side decelerates and stops at the specified spindle deceleration speed.

The coiling method of the polylactic acid monofilament in the present invention is as follows, and the coil can be made by combining the coiling conditions of the coiling tension, the surface pressure, the width of the traverse swing, and the deceleration speed of the coiling spindle. The CV value (%) of end surface hardness and package end surface hardness is within an appropriate range.

First, it is preferable to perform coiling at a coiling tension of 0.04 to 0.10 cN/dtex. This take-up tension is controlled by, for example, the speed difference between the first godet rolls 7, 8 and the second godet rolls 9, 10 or the speed difference between the second godet rolls 9, 10 and the take-up device 15, etc.

Second, it is preferable that the surface pressure applied to the package 3 by the roller ring 12 is 50 to 125 N/m. This surface pressure system adjusts the air pressure used to set the surface pressure provided in the winding device 15, and sets it at a specified pressure. For example, when the surface pressure is set at 100N/m, when the roll width F is 70mm, and the number of windings of the paper tube wound on the winding side spindle 13 is 12 drums (drum), adjust the surface pressure setting. As for the air pressure, the pressure applied by the roller ring 12 to the spindle 13 was set at 84N.

Thirdly, it is preferable to make the traversing swing width of the traversing device 11 within a range of 3 to 5%. The pan swing amplitude is set relative to the pan set value. For example, in the case where the traverse amplitude is 3%, the traverse setting value is 2000cpm, and the traverse period is 4 seconds, the vibration is performed with a period of 4 seconds and a traverse speed of 1940~2060cpm.

Fourth, after the polylactic acid-based monofilament package 3 reaches a predetermined volume, the deceleration speed for decelerating the spindle is preferably 20 to 70 m/sec. The deceleration speed of the spindle is when the polylactic acid monofilament package 3 reaches the specified volume, the spindle 13 on the winding side and the spindle 14 on the standby side are turned, and the deceleration speed of the spindle on the standby side is based on the set The deceleration speed will decelerate and stop the spindle.

The oiling agent in the manufacturing method of the polylactic acid monofilament package of this invention is carried out using the well-known spinning oiling agent and oiling apparatus. As the spinning oil, any form of commonly used spinning oil, such as a straight oil diluted with mineral oil or an emulsion oil diluted with water, can be used. Examples of the smoothing agent component or emulsifier component in the spinning oil component include ester-based, mineral oil-based, ether-ester-based smoothing agents, or ether-type nonionics having polyoxyalkylene groups in the molecule. Surfactant or polyol partial ester type nonionic surfactant or polyoxyalkylene polyol fatty acid ester type nonionic surfactant, etc. Examples of the oil supply system include an oil roller system, an oil supply guide system, and the like. The preferred adhesion amount of the oil agent to the fibers is 0.3-1.0 wt%, more preferably 0.5-0.8 wt%.

In the manufacturing method of the polylactic acid-based monofilament package of the present invention, heat stretching is usually performed using a godet roll, and the heat stretching temperature is in the range of 80 to 120°C. The heated stretching is preferably stretched using a heated godet roll, and the temperature of the godet roll is a value measured by a contact thermometer.

The godet rollers include, for example, a first godet roller and a second godet roller. In order to improve the followability of the yarn, it is preferable to use Nelson godet rollers with two godet rollers as a pair. The drawing system is carried out with the first godet roller, and the stretching system is carried out between godet rollers with different speeds. For example, in the case of one-stage drawing, it is performed between the first and second godet rolls. In the case of two-stage drawing, it is carried out between the first and second godet rolls and between the second and third godet rolls. It does not matter how much the stretching ratio and the number of stretching stages are, but it is preferably 3.5 to 4.5 times the stretching ratio and one stage of stretching. The temperature of the leading godet roll (first godet roll) is in the range of 80°C to 120°C. By setting the first godet temperature to 80°C or higher, uniform stretching can be achieved without uneven crystal structure, and stable quality can be obtained without devitrification or decrease in tensile strength. By setting the temperature of the first godet roller to 120°C or lower, it is possible to suppress yarn breakage due to a decrease in spinning tension and obtain stable operability. More preferably, it is below 90°C to 110°C.

The temperature of the drawing godet (second godet) is in the range of 100°C to 130°C. By setting the temperature of the second godet roll to 100°C or higher, the orientation crystallinity can be improved and the boiling water shrinkage of the polylactic acid monofilament can be reduced. By setting the temperature of the second godet roller to 130°C or lower, it is possible to suppress yarn breakage due to a decrease in winding tension and obtain stable operability. More preferably, it is 110°C~120°C.

As the cross-sectional shape of the polylactic acid-based monofilament constituting the cylindrical package of the present invention, it may be a circular cross-section, a Y-shaped cross-section, a T-shaped cross-section, a flat cross-section, or a shape that further deforms them.

[Example]

The following examples illustrate the present invention in more detail. In addition, the physical property value in an Example was measured by the method described below.

(1) Denier (dtex)

Measured according to JIS L1013 (2010) 8.3.1 fineness based on corrected weight (method A). In addition, the official moisture content is 0%.

(2) Roll thickness (mm)

It is the thickness A in the thickness direction of the package.

(3) Hardness of package end face

It is the value indicated by the pointer when the C-type indenter of the Asker Rubber Hardness Tester is pushed to the end surface of the package (according to JIS K7312:1996). The measurement position is at the 25mm thick portion of the package, and the measurement is performed at 36 positions while shifting the measurement positions by 10° in the circumferential direction of the package.

(4) CV value of package end surface hardness (variation coefficient, %)

At the portion of the package with a thickness of 25 mm (see Figures 3 and 4), measurements were made at 36 locations while shifting the measurement positions by 10° in the circumferential direction of the package, and the CV value (coefficient of variation) of the measured values was calculated. ).

(5) Protrusion (%)

Calculated according to the following formula.

Package roll width D/(package maximum roll width E-package roll width D)×100.

(6) Saddle (mm)

Calculated according to the following formula.

(The largest diameter of the package B-the smallest diameter of the package C)/2.

(7) Wire drop (DM/100DM)

Calculate the number of wire drop tubes on both ends of the package of 100 packages.

(8) Tensile strength (cN/dtex), tensile elongation (%)

Measured in accordance with JIS L1013 (2010) 8.5 tensile strength and elongation. In addition, the distance between clips was 500 mm, and the stretching speed was 500 mm/min. The average value of 3 replicate determinations was used.

(9) Boiling water shrinkage (%)

Measured in accordance with JIS L1013 (2010) 8.18.1. Use a length measuring machine with a frame circumference of 1.125m to make a skein yarn with 20 windings, measure the length of the skein yarn after standing for 24 hours, immerse it in boiling water (99±1.0°C) for 30 minutes, and measure the natural drying After the skein length, the boiling water shrinkage (%) was calculated from the skein length before and after boiling water immersion.

(10) Coiling tension (cN/dtex)

Assuming that the TENSION METER and FT-R pick-up sensor manufactured by Toray Engineering Co., Ltd. are used, the value measured from the second godet rollers 9 and 10 to the winding device 15 shown in FIG. 2 is divided by the fineness The resulting value (cN/dtex).

(11)Number of stripping packages (DM/100DM)

Prepare 100 polylactic acid-based monofilament tubular packages with a roll thickness of 40mm and a filament weight of 1kg, and use the loom of the air-jet loom at a speed of 1000m/min and 1200m/min (unwinding speed of the package) respectively. Weft evaluation, calculate the number of coils that have been stripped.

(12) Fabric quality

Prepare 100 polylactic acid-based monofilament cylindrical packages with a roll thickness of 40mm and a yarn weight of 1kg, and perform beating-up evaluation at a speed of 1200m/min with an air-jet loom. The brightness of the lighting is 250 lux or more. Check the appearance at a location below lux, and observe the band-like luster of the gray fabric and the defects of ring removal. The state where there is no band-shaped poor gloss or ring-off defect is judged as A, the state where band-like gloss difference or ring-off defect is slightly seen is judged as B, and the state where poor gloss or ring-off defect is seen intermittently is judged as C, The state where a large amount of poor gloss or ring-off defects are seen intermittently is judged as D, judged on a scale of 4, and grades A and B are regarded as pass.

(13) Weight average molecular weight

The measurement was performed using Gel Permeation Chromatography 2690 manufactured by Waters Co., Ltd., using polystyrene as a standard.

(14) Polylactic acid polymer (P)

Lactide produced from L lactic acid with an optical purity of 99.5% was placed in a nitrogen atmosphere in the presence of a bis(2-ethylhexanoate) tin catalyst (mol ratio of lactide to catalyst = 10000:1) The polymerization was carried out at 180° C. for 180 minutes to obtain a polylactic acid polymer P.

[Example 1]

Using the spinning device shown in Fig. 2, polylactic acid polymer P having a weight average molecular weight of 200,000 was melted at 230°C, supplied to the melt spinning unit, and the filaments discharged from the discharge holes of the spinning nozzle 5 were cooled. After applying the pure (straight) spinning oil (adherence: 0.8% by weight) diluted with mineral oil by the oil supply device 6 of the oil roller method, the first godet roller 7 heated to 100 ° C , 8 and the second godet rollers 9 and 10 heated to 115°C are stretched to 4.0 times. After heat treatment, the traversing device 11 of the micro-cam traversing method is used to oscillate at a twill angle of 5.6°. The amplitude of movement is 3%, the cycle of traversing is 4 seconds to make it traversing, while the surface pressure is 85N/m, the RB drive OF rate is 0.1%, the set coiling speed (V) is 3000m/min, and the spindle deceleration speed is 25m/sec. Under the manufacturing conditions, a cylindrical package of polylactic acid monofilament with a roll width of 70 mm, a roll thickness of 40 mm, a roll weight of 1.0 kg, and 25 dtex was obtained.

The end surface hardness of the package is 36~65, the CV value of the end surface hardness of the package is 10%, there is no wire collapse or drop, and the package form is good. Using the obtained package, the beating-up evaluation was carried out (polylactic acid monofilament of 25 dtex in the warp), and the results showed that there was no detachment at the unwinding speed of 1000m/min, and only 2 packages occurred even at the unwinding speed of 1200m/min The level of stripping and high-speed unwinding are good. Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was at the B level to the extent that a band-like luster was slightly poor or a ring-off defect was seen, and it was a pass level and the quality was good.

[Example 2]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1 except that the width of the lateral movement was changed to 4%. The hardness of the end surface of the package is 50~65, the CV value of the hardness of the end surface of the package is 7%, and there is no collapse or drop of the wire on the end surface of the package, which is good. The obtained package was subjected to the beating-up evaluation in the same manner as in Example 1. As a result, there was no loop dropout at any unwinding speed, and the high-speed unwinding property was good. Also, the quality of the weft-beaten fabric at an unwinding speed of 1200 m/min was A-level and good quality without band-like luster or loop dropout. That is, it is a package corresponding to an increase in the weaving speed, which has excellent high-speed unwinding performance of the package, high passability during weaving, and excellent yarn fabric quality.

[Example 3]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1 except that the width of the lateral movement was changed to 5%. The hardness of the end surface of the package is 45~63, the CV value of the hardness of the end surface of the package is 7%, and there is no collapse or drop of the wire on the end surface of the package, which is good. The obtained package was subjected to beating evaluation in the same manner as in Example 1. As a result, there was no lapping at an unwinding speed of 1000 m/min, and even at an unwinding speed of 1200 m/min, there was only one package at the level of lapping. Good unwinding property. Also, the quality of the fabric beaten up at an unwinding speed of 1,200 m/min was good at a B level to the extent that a band-like luster was slightly poor or a loop-off defect was seen.

[Example 4]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1, except that the width of the traverse motion was changed to 4% and the deceleration speed of the spindle was changed to 50 m/sec. The hardness of the end surface of the package is 40~67, and the CV value of the hardness of the end surface of the package is 10%. It is good if there is no wire collapse or loss on the end surface of the package. The obtained package was subjected to the beating evaluation in the same manner as in Example 1. As a result, there was no lapping at an unwinding speed of 1000 m/min, and even at an unwinding speed of 1200 m/min, there were only 2 packages at the level of lapping. Good unwinding property. In addition, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was good at a B level to the extent that a band-like luster was slightly poor or a ring-off defect was seen.

[Example 5]

Except that the width of the traverse shaking was changed to 4%, and the deceleration speed of the spindle was changed to 70m/sec, a cylindrical package of polylactic acid monofilament was obtained under the same conditions as in Example 1. The hardness of the end surface of the package is 38~65, the CV value of the hardness of the end surface of the package is 10%, and it is good if there is no collapse or drop of the wire on the end surface of the package. The obtained package was subjected to the beating-up evaluation in the same manner as in Example 1. As a result, there was no lapping at an unwinding speed of 1000 m/min, and even at an unwinding speed of 1200 m/min, there were only 3 packages at the level of lapping. Good unwinding property. In addition, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was good at a B level to the extent that a band-like luster was slightly poor or a ring-off defect was seen.

[Example 6]

A tubular package of 30 dtex polylactic acid-based monofilament was obtained under the same conditions as in Example 1 except that the traverse amplitude was changed to 4% and the amount of polymer discharged from the spinning nozzle 5 discharge hole was changed. The hardness of the end surface of the package is 50~60, the CV value of the hardness of the end surface of the package is 7%, and there is no collapse or drop of the wire on the end surface of the package, which is good. The obtained package was subjected to the beating-up evaluation in the same manner as in Example 1. As a result, there was no loop dropout at any unwinding speed, and the high-speed unwinding property was good. Also, the quality of the weft-beaten fabric at an unwinding speed of 1200 m/min was A-level and good quality without band-like luster or loop dropout. That is, as the weaving speed increases, the high-speed unwinding property of the package is excellent, and the high-pass property during weaving and the quality of the excellent yarn fabric are obtained.

[Example 7]

In addition to changing the speed difference between the second godet rolls 9, 10 and the take-up device 15, adjusting the take-up tension to 0.10cN/dtex, and changing the amount of polymer discharged from the spinning nozzle 5 discharge hole, in the same manner as in Example 1 A tubular package of polylactic acid monofilament of 30 dtex was obtained under the same conditions. The hardness of the end surface of the package is 45~70, and the CV value of the hardness of the end surface of the package is 10%. It is good if there is no collapse or loss of wires on the end surface of the package. The obtained package was subjected to the beating evaluation in the same manner as in Example 1. As a result, there was no lapping at an unwinding speed of 1000 m/min, and even at an unwinding speed of 1200 m/min, there were only two packages at the level of lapping. Good unwinding properties. In addition, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was good at a B level to the extent that a band-like luster was slightly poor or a ring-off defect was seen.

[Comparative example 1]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1, except that the traverse amplitude was changed to 2% and the spindle deceleration speed was changed to 50 m/sec. The hardness of the end face of the package is 32~66, and the CV value of the hardness of the end face of the package is 16%. Although there is no wire drop on the end face of the package, the wire collapse occurs at the part where the hardness of the end face of the package is low. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 7 packages at an unwinding speed of 1000 m/min, and 15 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and the high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor at C level to the extent that band-like luster was poor or looping defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative example 2]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1, except that the traverse amplitude was changed to 2% and the spindle deceleration speed was changed to 90 m/sec. The hardness of the end surface of the package is 30~64, and the CV value of the hardness of the end surface of the package is 16%. Although there is no wire drop on the end surface of the package, the wire collapse occurs at the part where the hardness of the end surface of the package is low. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 10 packages at an unwinding speed of 1000 m/min, and 20 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor in quality at the D level to the extent that a large number of band-like luster and dropout defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative example 3]

In addition to changing the traverse vibration range to 2%, change the speed difference between the second godet rollers 9, 10 and the take-up device 15, adjust the take-up tension to 0.12cN/dtex, and change the spindle deceleration speed to 50m/sec Except that, under the same conditions as in Example 1, a cylindrical package of polylactic acid-based monofilament was obtained. The hardness of the end surface of the package is 25~70, and the CV value of the hardness of the end surface of the package is 18%. Although there is no wire drop on the end surface of the package, the wire collapse occurs at the part with low hardness of the end surface of the package. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 10 packages at an unwinding speed of 1000 m/min, and 21 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor in quality at the D level to the extent that a large number of band-like luster and dropout defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative example 4]

A tubular package of polylactic acid monofilaments of 30 dtex was obtained under the same conditions as in Example 1, except that the traverse amplitude was changed to 8% and the amount of polymer discharged from the spinning nozzle 5 discharge hole was changed. The hardness of the end surface of the package is 20~65, and the CV value of the hardness of the end surface of the package is 21%. The wire drop of the end surface of the package also occurs in 55 tubes, and the wire collapse also occurs in the parts with low hardness of the end surface of the package. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 25 packages at an unwinding speed of 1000 m/min, and 45 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and the high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor in quality at the D level to the extent that a large number of band-like luster and dropout defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative Example 5]

A tubular package of polylactic acid-based monofilament was obtained under the same conditions as in Example 1, except that the traversing vibration range was changed to 4% and the spindle deceleration speed was changed to 100 m/sec. The hardness of the end surface of the package is 32~65, and the CV value of the hardness of the end surface of the package is 17%. Although there is no wire drop on the end surface of the package, the wire collapse occurs at the part where the hardness of the end surface of the package is low. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 4 packages at an unwinding speed of 1000 m/min, and 9 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and the high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor at C level to the extent that band-like luster was poor or looping defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative Example 6]

A cylindrical package of polylactic acid monofilament was obtained under the same conditions as in Example 1 except that the lateral shaking range was changed to 4% and the surface pressure was changed to 150 N/m. The hardness of the end surface of the package is 22~66, and the CV value of the hardness of the end surface of the package is 20%. The wire drop of the end surface of the package also occurs in 2 tubes, and the wire collapse occurs at the part with low hardness of the end surface of the package. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 14 packages at an unwinding speed of 1000 m/min, and 21 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor in quality at the D level to the extent that a large number of band-like luster and dropout defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

[Comparative Example 7]

In addition to changing the traversing shaking range to 4%, changing the speed difference between the second godet rollers 9, 10 and the take-up device 15, and changing the take-up tension to 0.15cN/dtex, under the same conditions as in Example 1 A cylindrical package of polylactic acid-based monofilament was obtained. The hardness of the end surface of the package is 21~68, the hardness CV value of the end surface of the package is 20%, and the wire drop of the end surface of the package also occurs in 3 tubes, and the wire collapse occurs at the part with low hardness of the end surface of the package. The obtained package was subjected to beating-up evaluation in the same manner as in Example 1. As a result, there were 13 packages at an unwinding speed of 1000 m/min, and 21 packages at an unwinding speed of 1200 m/min. A large number of loops occurred, and high-speed unwinding performance was poor. . Also, the quality of the fabric beaten up at an unwinding speed of 1200 m/min was poor in quality at the D level to the extent that a large number of band-like luster and dropout defects were intermittently seen. That is, it can be seen that it is a package that cannot cope with an increase in the weaving speed.

Claims (1)

A tubular package containing polylactic acid-based monofilaments, which is a cylindrical package containing more than 50% by weight of polylactic acid-based monofilaments composed of lactic acid monomers, characterized in that: the thickness of the package is 25mm Each value of the end surface hardness measured at 36 positions at 10° intervals is in the range of 35 to 70, and the CV value (variation coefficient, %) of the end surface hardness is below 15%.

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