RU2748416C2 - Hollow polyester filament fiber and method for production thereof - Google Patents

Abstract

FIELD: fibers.

SUBSTANCE: invention relates to a hollow polyester filament fiber of hollow goffered shape and to a method of manufacture thereof wherein the hollow fiber is suitable for manufacturing filament fibrous filler. The proposed fiber comprises a cross-sectional cavity in the range of 20.0 to 45.0% and has in a natural state a three-dimensional goffered shape. The goffered shape has a curvature radius in the range of 10.0 to 50.0 mm.

EFFECT: proposed fiber is suitable for processing into a fluffed processed tape with high fluffiness (voluminosity) which can be used as filament fibrous filler.

7 cl, 4 dwg, 3 tbl, 25 ex

Description

Scope of technical application

The present invention relates to a hollow long polyester fiber having a hollow corrugated shape and to a method for making the same, wherein the hollow long fiber is suitable for making a long fiber filler.

Background to the invention

In the textile industry, down jackets, sleeping bags and various heat-protective and heat-retaining products are usually filled with feathers and down of a waterfowl, for example, goose down, duck down, etc. The avian flu, which has appeared worldwide, has led to a strong decline in fluff production, which has caused prices to rise. At the same time, buyers also began to question the safety of fluff. If a natural feather is not washed properly, it will give off a bad smell. Therefore, it is necessary to remove the foul-smelling contamination in advance and to keep the pen clean. In addition, there are still problems associated with washing the feathers with which articles such as feather bedding, feather jackets, and the like are filled.

Therefore, the industry began to use synthetic fibers instead of animal fluff as filler. Chinese Patent CN1861871A discloses a type of short fiber fluffy filler, but the short fiber filler has a low looseness (bulk), and the thermal insulation material made from it creates

a gritty feel when touched, and the fluffy short fiber filler is prone to displacement during washing. Thus, there is an urgent need to create a new type of filler instead of fluff. Polyester fiber is easy to manufacture and has the advantage of low cost. The development of a filler based on polyester fiber has good market prospects.

BRIEF DESCRIPTION OF THE INVENTION

An object of the present invention is to provide a hollow long polyester fiber having a three-dimensional corrugated shape suitable for use in the production of a long fiber filler and a method for making a hollow long polyester fiber.

The hollow long polyester fiber according to the present invention has a cross-sectional cavity in the range of 20.0% to 45.0%; and the hollow long polyester fiber has a three-dimensional corrugation in its natural state, and the corrugations have a radius of curvature ranging from 10.0 mm to 50.0 mm.

The hollow long polyester fiber according to the present invention preferably has a filament linear density in the range of 4.0 dtex to 15.0 dtex, and more preferably 5.0 dtex to 10.0 dtex.

The hollow long polyester fiber of the present invention still has a three-dimensional crimp shape after dry heat treatment at 160 ° C for 3 minutes, and has a crimped radius of curvature ranging from 3.5 mm to 10.0 mm.

The hollow long polyester fiber according to the present invention contains a polymeric raw material selected from the group consisting of: polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, or modified polymers thereof.

The present invention also discloses a method of manufacturing the aforementioned hollow long polyester fiber, according to which dried pellets are melted and extruded using a screw extruder, and then transported to a metering pump through a pipe; the amount of polymer supplied, measured with high precision by means of a metering pump, is transported to the die block, where the die of the die block is a hollow die with a cooling section ranging from 10 mm to 150 mm; where the side air flow velocity is in the range from 25 m / min to 90 m / min.

The cooling portion is preferably 60 mm to 110 mm; the side air flow velocity is in the range from 30 m / min to 50 m / min.

The hollow long polyester fiber according to the present invention is obtained by using a melt spinning process; this process has the advantages of ease of production and low cost, and the ability to give the fiber a three-dimensional corrugated structure; and this fiber is suitable for processing into a fluff treated tape that can be used as a long fiber filler.

Brief Description of Drawings

FIG. 1 shows a long polyester fiber with a triangular cavity in cross section;

in fig. 2 shows a long polyester fiber with a quadrangular cavity in cross section;

in fig. 3 shows a hollow long polyester fiber having a three-dimensional corrugated shape in its natural state;

in fig. 4 is a schematic view illustrating the process of measuring the radius of curvature.

DESCRIPTION OF EMBODIMENTS

To provide a filler that could replace fluff, the present invention provides a hollow, long polyester fiber suitable for processing into a fluff processed web. Since the hollow fiber has a structural feature characterized by a three-dimensional corrugated shape, the obtained, fluffed, processed tape also has a three-dimensional structure, due to which the volume of the fluffed ribbon is large, and a fluffed processed ribbon with very good fluff (bulk) can be obtained. Among the polymers from which the fiber is formed, the polyester fiber possesses a relatively high Young's modulus, so that the resulting, fluffed, treated tape has good compressive strength and bulk recovery.

By three-dimensional corrugation is meant that the fiber has an irregular helical structure in the length direction (see Fig. 3), and at the same time, due to the difference in alignment between the filament parts, the angles of rotation and directions of the filaments are different. due to which a multidimensional stereoscopic form is formed.

The hollow long polyester fiber of the present invention is a hollow fiber made using melt spinning technology. The molten polyester pellets are discharged through a profiled hollow die and then coiled after cooling with a side air stream to obtain a hollow long polyester fiber. During the melt spinning process, the hollow fiber is controlled to have a cavity in the range of 20.0% to 45.0% <of the fiber cross-sectional area>; so that the radius of curvature of the three-dimensional corrugated fiber is in the range from 10.0 mm to 50.0 mm, adjust the position of the side air flow <source> to change the cooling section; adjust the lateral air flow rate and the spinning speed. Compared to a solid fiber with the same fiber diameter, a fluffed, processed, filament obtained by using a hollow fiber has a higher fluff (bulk); and the larger the cavity, the more obviously a lower fiber weight is obtained. If the radius of curvature of the hollow fiber is too small, then the adhesion between the filaments is high; the fibers are not easily separated during the belt fluffing process, and the diameter of the ring formed from the fiber is small, which adversely affects the fluff (bulk) of the processed belt. On the other hand, if the radius of the corrugation of the fiber is too large, then the diameter of the ring formed from the fiber after processing into a fluff processed tape is too large, which can lead to a weakening or deterioration of the reflection of the original three-dimensional effect of the fiber in the form of a shell, and also adversely affect fluffiness (bulk) of the processed tape.

According to the differences in the shape and arrangement of the outlets in the hollow die, and the change in the manufacturing process, the resulting hollow fiber has a slightly different cross-section, and the hollow part has a circular shape, an approximately triangular shape, an approximately square shape, an approximately pentagonal shape, and the like. At the same time, the number of holes in the hollow part of the "die" is not limited to one hole.

The linear density of the hollow long polyester filament according to the present invention is preferably in the range of 4.0 dtex to 15.0 dtex. Regarding the fiber raw material for the fluffed webbing, the higher the filament fineness, the more rigid the fiber becomes, and in addition, the fluffiness (bulk) of the resulting fluffed webbing is better, and the greater the compressive strength and recoverability. <volumetric>. However, if the diameter of the filament is too large, it is not easy to cool the fiber during spinning, and the uniformity of the fiber decreases, and the resulting fluffed tape has a stiffness to the touch. Thus, it is more preferable that the linear density of the hollow long polyester filament is in the range of 5.0 dtex to 10.0 dtex.

The raw materials for making the hollow, long, polyester fibers according to the present invention are mainly conventional polyesters, for example, polyethylene terephthalate, polytrimethylene terephthalate or polybutylene terephthalate. A modified copolymer of the above polymer, for example, an antibacterial and acaricidal modified polymer, can also be used to impart a special function to the fluffed treated yarn, and the same effect as using conventional polyester can be achieved in terms of providing fluff (bulk).

Hollow long polyester fiber is one of the raw materials for making fluffy processed filling belts. Hollow long polyester fiber can be directly used as a long fiber filler by directly joining N fibers into a fluffed treated belt, and can also be used in combination with other raw materials such as fiber with a slightly lower melting point to prepare a fiber blend and then used as long fiber filler. Alternatively, the blended fiber and the hollow long polyester fiber are spun into a core-sheath fiber and then partially melted to produce a better fluff treated web, which is then used as a long fiber filler.

The hollow long polyester fiber of the present invention still has a three-dimensional shape after dry heat treatment at 160 ° C for 3 minutes. The corrugated shape changes due to thermal shrinkage of the fiber, and the radius of curvature is preferably in the range of 3.5 mm to 10.0 mm. In this case, even after post-processing, the hollow long polyester fiber can maintain a fluffed, three-dimensional, crimped shape and give a very good feeling of fluff (bulk), warmth, and the like. when touched.

The hollow long polyester fiber according to the present invention can be produced by the following method, but its production is not limited to this method.

First, the raw material polyester granules are dried to reduce the water content of the polyester granules, improve formability and control the water content of the granules to be 50 ppm (parts per million) or less. The dried granules are used for melt spinning in a conventional manner. The pellets are melted using a screw or hot plate and then transported to a metering pump through a pipe, and the molten polymer is accurately dosed by the metering pump, after which it is introduced into a spinneret block using a spinneret to form a hollow fiber. The resin discharged from the spinneret is cooled, oiled and then coiled. To obtain a slightly corrugated hollow fiber, the requirements for the size of the cooling section (the distance from the bottom edge of the die to the top edge of the side blowing means for cooling) during fiber spinning are relatively strict, and this size is usually provided in the range from 10 mm to 150 mm, preferably in the range from 60 mm to 100 mm. At the same time, in order to provide a difference between the structures on both sides of the hollow fiber, there is also a limitation on the side blowing air flow rate. According to the type of fiber (total linear density and number of filaments), the air flow rate is usually provided in the range from 25 m / min to 90 m / min, preferably from 30 m / min to 50 m / min.

If the size of the cooling section is less than 10 mm, the polymer discharged from the die is rapidly cooled, the asymmetry effect is obvious, the radius of curvature of the resulting fiber is too small, the adhesion between the filaments is strong, and the fluff effect is reduced, and at the same time, the temperature of the die is rapidly reduced. causing fiber breakage and thus reducing fiber spinability. If the size of the cooling section is greater than 150 mm, then the polymer discharged from the die is uniformly cooled to a certain degree. Even if further cooling is performed by means of lateral blowing, the asymmetry effect is weakened, and the radius of curvature of the fiber is too large, which also adversely affects the fluff effect.

If the air flow velocity with side blowing is less than 25 m / min, the asymmetric cooling effect is not obvious and the radius of curvature of the fiber is too large. If the side blowing air speed is more than 90 m / min, the asymmetry effect is obvious, and this results in too small a radius of curvature of the resulting fiber, and due to the excessive side blowing, there is strong fiber swing, unstable fiber spinning, and easily appear floating filaments and dangling filaments.

In order to prevent differences in the physical properties of filaments due to differences in cooling, the arrangement of the outlets in the die preferably has a "tweed" pattern, which is often referred to as a diamond arrangement. Preferably, the fiber spinning process is generally a one step fiber spinning process, i. E. that the spinning and drawing processes take place simultaneously, i.e. processes commonly known as fully oriented filament (FO) processes. However, fiber can also be produced using a two-step process in which a pre-oriented fiber, commonly known as a partially oriented yarn (PF), is first produced, which is then drawn on a stretching machine, which is commonly known as a stretching machine (PM).

The hollow long polyester fiber according to the present invention has a three-dimensional corrugated structure, and at the same time, the filament is relatively thick, and the fluff processed tape obtained from the hollow long fiber has an extremely high bulk, and a large fluff (bulk), while having a very high resistance to compression.

Test methods used according to the present invention

(1) Method for determining the total linear density and linear density of a filament

The total linear density was determined according to JIS L 1013: 2010, and the linear density of a filament was calculated based on the total linear density and the number of filaments.

(2) Determination of the fraction of the cavity in the fiber

The hollow long fiber was cut into thin plates (i.e., fiber cross-sections were made) in the transverse direction of the fiber, which were then photographed under a conventional optical microscope at an appropriate magnification, and the area S _{1 of the} hollow part and the area S _{2 of the} entire fiber (including the hollow part ) from the photograph, then the fraction of the hollow part was calculated:

Hollow fraction = (S ₁ / S ₂ ) × 100%.

(3) Method for determining the radius of curvature

Natural radius of curvature: the filament was passed through a scaler (for measuring linear density) to corrugate the sample to create 10 turns (1 m / turns), and then the sample to be tested was placed (hung) for 8 hours or more in the chamber, in which the temperature and relative humidity (20 ° C × 65% RH) were kept constant to stabilize its condition (see Fig. 3), then the corrugated part at a distance of 20 cm below the sample suspension point was chosen for measuring the radius, and 20 different places was chosen for measurement and determination of the average value, and the obtained value was taken as the radius of curvature. A digital microscopic system (VHX-2000C) from KEYENCE was used as a measuring instrument. The magnification was 20x and the radius of curvature was measured by calculating the radius of curvature function using software (see FIG. 4). Those. the radius of curvature of the fiber was measured using three points on the corrugated fiber.

Radius of curvature after dry heat treatment: The filament was passed through a scaler (for measuring linear density) to crimp the sample to create 10 turns, and then placed in a drying chamber for heat treatment. Processing conditions: 160 ° C for 3 minutes, and then the sample was placed in a chamber in which the temperature and relative humidity were kept constant for 4 hours or more, and finally, the corrugated part 20 cm long at the bottom was selected to measure the radius, and 20 different locations were selected to measure and average, and the resulting value was taken as the radius of curvature.

(4) Fluffiness (volume)

The tests were carried out according to the IDFB method.

(i) First, the sample to be tested was placed in an environment in which the temperature and relative humidity (20 ° C × 65% RH) were kept constant for 8 hours or more to stabilize the sample to be tested;

(ii) 30 g of the sample was weighed, shaken by hand to bring to a fluffy state, placed in a measuring container and covered with a lid;

(iii) the weight plate was lowered to the highest point of contact with the sample, then the weight plate was released, allowing it to fall freely, and the time from the moment the weight plate was released was measured, and after 1 minute for stabilization, the height position of the plate was read and recorded. value;

(iv) the lid was opened to remove the sample, which was again shaken until fluffed, placed in a measuring container and covered with a lid, and measured again according to step (iii), and these steps were repeated 5 times;

(v) fluffiness (bulk) was calculated by determining the average position of the plate in height from 5 tests.

The content of the present invention is explained below by examples, but the present invention is not limited to the content listed in the examples.

Example 1

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 25 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type - 300T-20f; hollow fiber with a triangular cross section; the proportion of the cavity was 20.0%; the linear density of the filament was 15.0 dtex; the radius of curvature was 50.0 mm before heat treatment and 10.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to produce a treated fluff tape, where the fluff (bulk) of the treated fluff tape was determined by the volume of 30 g of tape, which was 390 inches ³ (6392.1 cm ³ ). See Table 1 for details.

Example 2

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 40 m / min; and a hollow polyester fiber was obtained using a high speed dry fiber spinning process. The characteristics of the hollow fiber were as follows: fiber type 150T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 15.0 dtex; the radius of curvature was 42.0 mm before heat treatment and 8.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 600 inches ³ (9834.0 cm ³ ). See Table 1 for details.

Example 3

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 40 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 60T-4f; hollow fiber with a triangular cross section; the proportion of the cavity was 45.0%; the linear density of the filament was 15.0 dtex; the radius of curvature was 37.0 mm before heat treatment and 7.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 800 inches ³ (13112.0 cm ³ ). See Table 1 for details.

Example 4

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 10.0 dtex, and the radius of curvature was 40.0 mm before heat treatment and 7.8 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 650 inches ³ (10647.0 cm ³ ). See Table 1 for details.

Example 5

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 50 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-20f; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 5.0 dtex and the radius of curvature was 35.0 mm before heat treatment and 6.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of tape, which was 610 inches ³ (9991.8 cm ³ ). See Table 1 for details.

Example 6

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 75 m / min; and a hollow polyester fiber was obtained using a high speed high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 60T-15f; hollow fiber with a triangular cross section; the proportion of the cavity was 45.0%; the linear density of the filament was 4.0 dtex and the radius of curvature was 10.0 mm before heat treatment and 3.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 480 inches ³ (7867.2 cm ³ ). See Table 1 for details.

Example 7

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 70 m / min; and a hollow polyester fiber was obtained using a high speed high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were: 65T-10f fiber type; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 6.5 dtex and the radius of curvature was 30.0 mm before heat treatment and 6.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of tape, which was 580 inches ³ (9504.5 cm ³ ). See Table 1 for details.

Example 8

As a raw material, semi-matte polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 70 m / min; and a hollow polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: 50T-10f fiber type; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 5.0 dtex and the radius of curvature was 20.0 mm before heat treatment and 4.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the manufacture of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed processed tape was determined by the volume of 30 g of tape, which was 520 inches³(8522.8 cm³). See Table 1 for details.

Example 9

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 25 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 60T-4f; hollow fiber with a quadrangular cross-section; the proportion of the cavity was 45.0%; the linear density of the filament was 15.0 dtex and the radius of curvature was 42.0 mm before heat treatment and 8.1 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to produce a treated fluff tape, where the fluff (bulk) of the treated fluff tape was determined by the volume of 30 g of tape, which was 760 inches ³ (12456.4 cm ³ ). See Table 1 for details.

Example 10

As a raw material, conventional polytrimethylene terephthalate pellets (i.e. conventional 3GT) were used, where the polytrimethylene terephthalate pellets were dried using a pre-crystallization dewatering oven to adjust the water content to 30 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f, hollow fiber with triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 38.0 mm before heat treatment and 7.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 630 inches ³ (10325.7 cm ³ ). See Table 1 for details.

Example 11

As a raw material, conventional polybutylene terephthalate pellets (i.e., conventional PBT) were used, where the polybutylene terephthalate was dried using a pre-crystallization dewatering oven to adjust the water content to 33 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 35 m / min; and a hollow polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f, hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 36.0 mm before heat treatment and 7.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 600 inches ³ (9834.0 cm ³ ). See Table 2 for details.

Example 12

As a raw material, granules of cationically modified polyethylene terephthalate were used, where the cationically modified polyethylene terephthalate was dried using a pre-crystallization, dehydrating, drying chamber to bring the water content to 30 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f, hollow fiber with triangular cross section; the proportion of the cavity was 33.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 33.0 mm before heat treatment and 6.4 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of tape, which was 610 inches ³ (9991.8 cm ³ ). See Table 2 for details.

Example 13

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 10 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 40.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 12.0 mm before heat treatment and 3.6 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of tape, which was 490 inches ³ (8031.1 cm ³ ). See Table 2 for details.

Example 14

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 60 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 37.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 30.0 mm before heat treatment and 6.1 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 600 inches ³ (9834.0 cm ³ ). See Table 2 for details.

Example 15

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 90 mm cooling section. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 32.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 34.0 mm before heat treatment and 9.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 720 inches ³ (11800.8 cm ³ ). See Table 2 for details.

Example 16

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a cooling section of 110 mm in length. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 30.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 38.0 mm before heat treatment and 12.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 620 inches ³ (10161.8 cm ³ ). See Table 2 for details.

Example 17

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a cooling section of 150 mm in length. The side air flow velocity was 35 m / min; and a polyester hollow fiber was obtained by a high speed dry spinning process of [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 25.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 44.0 mm before heat treatment and 14.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and each 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 550 inches ³ (9014.5 cm ³ ). See Table 2 for details.

Example 18

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 90 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 35.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 18.0 mm before heat treatment and 3.9 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 510 inches ³ (8358.9 cm ³ ). See Table 2 for details.

Example 19

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow velocity was 50 m / min; and a polyester hollow fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the fraction of the cavity was 28.0%, the linear density of the filament was 10.0 dtex, and the radius of curvature was 28.0 mm before heat treatment and 4.5 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 530 inches ³ (8686.7 cm ³ ). See Table 2 for details.

Comparative example 1

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the spinneret was a conventional circular orifice die with a 65 mm cooling section. The side airflow velocity was 25 m / min; and a polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 56T-24f; the fiber had a solid circular cross-section; the linear density of the filament was 2.3 dtex; and the fiber had no crimp before and after heat treatment. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 240 inches ³ (3933.6 cm ³ ). See Table 3 for details.

Since the fiber was solid in cross-section, the resulting fiber had no crimp, had little fluff (bulk), and was not suitable for use as a fibrous filler instead of a feather.

Comparative example 2

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 90 mm cooling section. The side air flow velocity was 35 m / min; and a polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 10.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 40.0 mm before heat treatment and 10.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 310 inches ³ (5080.9 cm ³ ). See Table 3 for details.

Since the fiber cavity was too small, although it had a radius of curvature, it was not light and had little fluff (bulk), and was not suitable for use as a fibrous filler instead of a feather.

Comparative example 3

As a raw material, semi-matte polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 5 mm cooling section. The side air flow velocity was 35 m / min; and a polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. Since the cooling section was too short, although spinning could take place, the occurrence of broken filaments and floating filaments was severe and the feasibility of production was low. See Table 3 for details.

Comparative example 4

As a raw material, semi-matte polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side air flow rate was 110 m / min, and a polyester fiber was obtained using a high speed dry spinning [SPF (P)] fiber process. Since the side blowing air velocity was too high, although spinning could occur, severe fiber vibration resulted in severe filament breaks and floating filaments, and production feasibility was low. See Table 3 for details.

Comparative example 5

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 200 mm long cooling section. The side airflow velocity was 70 m / min; and a polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the proportion of the cavity was 15.0%; the linear density of the filament was 10.0 dtex and the radius of curvature was 65.0 mm before heat treatment and 23.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 350 inches ³ (5082.0 cm ³ ). See Table 3 for details.

Since the cooling portion was too large, the radius of curvature of the resulting fiber was too large to reflect the three-dimensional effect of the fiber, resulting in little fluff (bulk).

Comparative example 6

As a raw material, semi-gloss polyester beads (T200N from Toray Fibers (Nantong) Co., Ltd.) were used; the polyester granules were dried using a pre-crystallization, dewatering, drying chamber to adjust the water content to 39 ppm after drying. The dried granules were melted and extruded by means of a screw extruder, and transported to a metering pump through a pipe. The polymer, dosed with high precision by means of a metering pump, was transported to the die block. The die of the die block was a special hollow die with a 65 mm cooling section. The side airflow velocity was 20 m / min; and a polyester fiber was obtained using a high speed dry spinning process [SPF (P)] fiber. The characteristics of the hollow fiber were as follows: fiber type 100T-10f; hollow fiber with a triangular cross section; the fraction of the cavity was 12.0%, the linear density of the filament was 10.0 dtex, and the radius of curvature was 55.0 mm before heat treatment and 20.0 mm after dry heat treatment at 160 ° C for 3 minutes. The fiber was chosen as a raw material for the production of fiber cladding and fiber core, and was fed in excess at 20 times the feed rate of the <material> of the filament cladding relative to the feed rate of the filament core <material>, producing fluffy filaments with a core-sheath structure ; and every 6 filaments were combined into one to obtain a fluffed treated tape, where the fluff (bulk) of the fluffed treated tape was determined by the volume of 30 g of the tape, which was 350 inches ³ (5082.0 cm ³ ). See Table 3 for details.

Since the side airflow velocity was too low, the radius of curvature of the resulting fiber was too large to reflect the three-dimensional effect of the fiber, resulting in little fluff (bulk).

Claims (7)

1. A hollow polyester filament fiber having a cross-sectional cavity in the range of 20.0 to 45.0% and having a three-dimensional corrugated shape in its natural state, where the corrugated shape has a radius of curvature ranging from 10.0 to 50.0 mm. 2. The hollow polyester filament according to claim 1, having a linear density of a filament in the range of 4.0 to 15.0 dtex. 3. A hollow polyester filament according to claim 2, having a linear density of a filament in the range of 5.0 to 10.0 dtex. 4. A hollow polyester filament according to claim 1 or 2 having a radius of curvature ranging from 3.5 to 10.0 mm after dry heat treatment at 160 ° C for 3 minutes. 5. Hollow polyester filament fiber according to claim 1 or 2, for the production of which the polyester is selected from the group consisting of: polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate or modified polymers thereof. 6. A method of making a hollow polyester filament fiber according to claim 1, according to which the dried granules are melted and extruded by means of a screw extruder, and then transported to a metering pump through a pipe; the polymer, measured with high precision by means of a metering pump, is transported to the die block; where the die of the spinneret block is a hollow die with a cooling portion ranging from 60 to 110 mm, and the side blowing air flow rate is in the range from 25 to 90 m / min. 7. The method of manufacturing a hollow polyester filament according to claim 6, wherein the side blowing air flow rate is in the range of 30 to 50 m / min.

Images