KR102426436B1 - complex-fiber for the compressing molding body and Manufacturing method thereof - Google Patents

Abstract

The present invention relates to a fiber for a compression molded article and a method for manufacturing the same, and more specifically, to an invention capable of providing a composite fiber composed of two components having excellent moldability and shape stability, and a method for manufacturing the same.

Description

Composite fiber for compression molding and manufacturing method thereof

The present invention relates to a composite fiber capable of providing an application product having excellent mechanical properties related to moldability and shape stability, and a method for manufacturing the same with high mass productivity.

In general, application products of fiber aggregates such as non-woven fabrics have been used for various purposes, such as hygiene, medical, agricultural, or industrial use. In general, in order to obtain a product with high tensile strength, it is common to use a method of producing by increasing the weight per unit area. However, in the case of production by increasing the weight in this way, since the thickness of the product increases at the same time, there is a problem in that it is difficult to apply it to a product that is thin and requires strength.

Accordingly, glass fiber, carbon fiber, etc. are mixed with other fibers to compensate for insufficient mechanical properties of application products using fiber aggregates, thereby manufacturing and selling products having mechanical properties similar to or higher than those of plastic products. However, in the case of a product using such glass fiber, there is a problem that the glass fiber scatters from the product in the processing process and contaminates the working environment, and since glass fiber is known to cause lung cancer, glass fiber is recently used There is an increasing demand for the development of products having properties equal to or higher than those of products using glass fibers without doing so.

Republic of Korea Patent Registration No. 10-0899613 (Registration Date: 2009. 5. 20) Republic of Korea Patent Registration No. 10-1357018 (Registration Date: 2014.01.23)

The object of the present invention was devised to solve the above problems, and the object of the present invention is to have excellent mechanical properties such as tensile strength, flexural strength, and flexural modulus, while also providing sound absorption, sound dispersibility, water absorption, and water dispersibility. An object of the present invention is to provide a composite fiber capable of providing application products such as an excellent fiber aggregate, and also to provide a method for manufacturing it with high commerciality.

In order to solve the above problems, the composite fiber of the present invention is a bicomponent fiber including a first component resin and a second component resin, wherein the first component resin includes a polyester resin, and the second component resin is a crystalline polyolefin Including a resin, the difference in the melting point temperature of the first component resin and the second component resin may be 30 ℃ ~ 100 ℃.

In a preferred embodiment of the present invention, the crystalline polyolefin resin may have an enthalpy value of 40 to 120 J/g required to melt the crystal during differential thermal analysis (DSC) analysis.

As a preferred embodiment of the present invention, the first component resin includes a polyester resin having an intrinsic viscosity of 0.50 to 1.00 dl/g and a melting point of 200° C. or higher, and the polyester resin is a polyethylene terephthalate (PET) resin, polybutyl It may include at least one selected from a renterephthalene (PBT) resin, a polytrimethylene terephthalate (PTT) resin, and a polyethylene naphthalate (PEN) resin.

In a preferred embodiment of the present invention, the PET resin may include a polymer obtained by polymerizing terephthalic acid and a diol in a molar ratio of 1:0.95 to 1.20.

As a preferred embodiment of the present invention, the second component resin may include a crystalline polyolefin resin having a melting point of 150°C to 170°C, and the crystalline polyolefin resin is a crystalline polypropylene (PP) resin and a polyethylene resin. It may include one or more selected from among.

In a preferred embodiment of the present invention, the bicomponent fiber is a sheath-core fiber, a side-by-side fiber, a sea-islands fiber or It may be a segmented-pie type fiber.

In a preferred embodiment of the present invention, in the bicomponent fiber, the cross-sectional area ratio of the first component and the second component may be 1:0.5 to 1.

As a preferred embodiment of the present invention, the bicomponent fiber is a sheath-core type fiber, the sheath includes a crystalline polypropylene (PP) resin having a melting point of 150°C to 170°C, and the core is polyethylene terephthalate having a melting point of 200°C or higher. It may include a phthalate (PET) resin.

As a preferred embodiment of the present invention, the average fineness of the composite fiber of the present invention is 4 to 12 de, the average fiber length is 3 mm to 120 mm, and the number of crimps may be 9 to 15 pieces/inch.

As a preferred embodiment of the present invention, the surface of the composite fiber of the present invention may be modified, or a hydrophilic coating layer and/or a hydrophobic coating layer may be formed on the surface of the composite fiber.

Another object of the present invention relates to a method for producing the above-described composite fiber, the first step of preparing a polyester chip and a crystalline polyolefin chip, respectively; A second step of preparing an unstretched sub-tow by putting the first component resin and the second component resin in which the polyester chip and the crystalline polyolefin chip are melted, respectively, into a composite spinneret and composite spinning, followed by cooling; After stretching the unstretched sub tow, a third step of applying a crimp; and 4 steps of heat-setting and cutting the stretched and crimped sub tow;

In a preferred embodiment of the present invention, the subtow may be a sheath-core type monofilament, a side-by-side type monofilament, a sea-island type monofilament, or a split type monofilament.

As a preferred embodiment of the present invention, the two-step melting may be performed under 270°C to 300°C for the polyester chip, and 230°C to 280°C for the crystalline polyolefin chip.

As a preferred embodiment of the present invention, the two-step composite spinning may be performed under the conditions of a spinning temperature of 260°C to 290°C and a winding speed of 400 to 1,300 m/min.

Another object of the present invention is to provide a fiber assembly prepared by using the composite fiber of the present invention.

As a preferred embodiment of the present invention, the fiber aggregate may be a non-woven fabric.

In a preferred embodiment of the present invention, the non-woven fabric may be a dry-laid non-woven fabric, a wet-laid non-woven fabric or an air-laid non-woven fabric.

Another object of the present invention is to provide a compression molded article in which the fiber aggregate is laminated in one layer or in multiple layers and then compression molded.

As a preferred embodiment of the present invention, the compression molded article may further include a fiber aggregate layer comprising fibers of a different type from the fibers constituting the fiber aggregate.

The composite fiber of the present invention has excellent physical properties such as tensile strength, flexural strength, and flexural modulus, and has excellent bonding strength between composite fibers and excellent processability. It is suitable for application to several fiber aggregate application products that require such.

1 is an SEM photograph of a cross-section of the compression molded article prepared in Preparation Example 1.
2 is a SEM photograph taken of a cross-section of the compression molded article prepared in Preparation Example 2.
3 is an SEM photograph of a cross-section of the compression molded article prepared in Preparation Example 3.
4 and 5 are each a measurement result of shape stability of Preparation Example 1, Preparation Example 2, and Preparation Example 3 carried out in Experimental Example 2.

Hereinafter, the composite fiber of the present invention will be described in more detail.

The composite fiber of the present invention is a bicomponent fiber comprising a first component resin and a second component resin, a sheath-core type fiber, a side-by-side type fiber, It may be a sea-islands type fiber or a segmented-pie type fiber, preferably a sheath-core type fiber or a side-by-side type fiber.

The first component resin is related to the shape stability of a fiber aggregate such as a nonwoven fabric manufactured using the composite fiber of the present invention and a compression molded article to which the same is applied, so it is preferable to use a resin having an excellent modulus. In addition, the second component resin is preferably a material suitable for securing the shape stability and moldability of the fiber aggregate and/or compression molded body by securing adhesion between the composite fibers.

And, in the composite fiber of the present invention, the first component resin and the second component resin may have a melting point temperature difference of 30 ° C. to 100 ° C., preferably 40 ° C. to 90 ° C. In this case, if the melting point temperature difference is less than 30 ° C. When manufacturing a fiber aggregate using fibers, the fiber aggregate must be prepared under an appropriate temperature atmosphere so that the second component resin is properly melted in order to bond between the composite fibers due to the second component resin. Since the first component resin becomes brittle because the melting point temperature difference between the two parts is small, the mechanical properties of the fiber aggregate and the compression molded product using the same may be reduced, and there may be a problem of poor processability and moldability. As the temperature difference between the resins increases, the compatibility between the resins of the first component and the second component decreases, so that it may be difficult to manufacture a bicomponent composite fiber.

The first component resin may include a polyester resin, wherein the polyester resin is a polyethylene terephthalate (PET) resin, a polybutylene terephthalene (PBT) resin, a polytrimethylene terephthalate (PTT) resin, and a polyethylene or It may include a phthalate (PEN) resin, preferably at least one selected from a PET resin, a PBT resin, and a PEN resin, and more preferably a PET resin.

And, the first component resin has an intrinsic viscosity of 0.50 to 1.00 dl/g and a melting point of 200° C. or higher, preferably an intrinsic viscosity of 0.55 to 0.90 dl/g and a melting point of 230° C. to 280° C., more preferably an intrinsic viscosity It is recommended to use 0.60 to 0.75 dl/g and a melting point of 240°C to 265°C. At this time, if the intrinsic viscosity of the first component resin is less than 0.50 dl/g, there may be a problem in that the strength of the composite fiber decreases, and if the intrinsic viscosity exceeds 1.00 dl/g, there may be a problem in spinning and drawing workability have. In addition, if the melting point of the PET resin is less than 200 ° C., the melting point temperature difference with the second component resin is too small, so that there may be a problem in that processability, moldability, etc. are deteriorated when manufacturing an application product using the composite fiber. Therefore, PET having the melting point It is better to use resin.

And, when the polyester resin is a PET resin, a general PET resin used in the art may be used, and preferably, a polymer obtained by polymerizing terephthalic acid and a diol; in a molar ratio of 1: 0.95 to 1.20. Can be used.

Next, the second component resin may include a polyolefin resin.

As the crystalline polyolefin resin, at least one selected from polypropylene resin and polyethylene resin may be used, and polypropylene resin may be preferably used.

In addition, the crystalline polyolefin resin has an enthalpy value of 40 to 120 J/g required for dissolving the crystal during differential thermal analysis (DSC) analysis, preferably an enthalpy value of 70 to 115 J It is recommended to use /g.

In addition, the crystalline polyolefin resin has a melting point of 150 ° C. to 170 ° C., preferably 155 ° C. to 170 ° C., more preferably 160 ° C. to 170 ° C. In this case, the melting point of the crystalline polyolefin resin is less than 150 ° C. On the other hand, the difference in the melting point temperature with the polyester resin, which is the first component resin, is too large, so that the spinnability for manufacturing the bicomponent composite fiber is deteriorated, and the compatibility between the resins of the first and second components is poor, making it difficult to manufacture the bicomponent composite fiber. There may be a problem, and when the melting point exceeds 170° C., the difference in the melting point temperature between the first component and the second component resin becomes small, and thus there may be a problem in that processability is deteriorated.

And, the composite fiber of the present invention is a composite fiber composed of two components, and the fiber may have a cross-sectional area ratio of the first component and the second component of 1:0.5 to 1, preferably, a cross-sectional area ratio of 1:0.7 to 1. At this time, if the cross-sectional area ratio of the second component is less than 0.5, there may be a problem in that the bonding strength between the composite fibers is lowered. There may be a problem in that the modulus of a product manufactured by using it decreases.

When describing a preferred embodiment of the composite fiber of the present invention, the composite fiber of the present invention is a sheath-core type composite fiber, wherein the sheath comprises a crystalline polypropylene (PP) resin having a melting point of 150°C to 170°C, The core may include a polyethylene terephthalate (PET) resin having a melting point of 200° C. or higher.

In addition, the composite fiber of the present invention has an average fineness of 4 to 12 de, the average fiber length is 3 to 120 mm, and the number of crimps may be 9 to 15 pieces/inch, preferably the average fineness is 5 to 10 de, The average fiber length is 6 ~ 100 mm, the number of crimps may be 10 ~ 14 / inch, more preferably the average fineness is 5 ~ 9 de, the average fiber length is 20 ~ 100 mm, the number of crimps is 10 ~ 14 / can be inches. At this time, if the average fineness of the composite fiber is less than 4 de, there may be a problem in that the tensile strength of the fiber aggregate and/or compression molded body is lowered, and if it exceeds 12 de, the modulus of the fiber aggregate and/or the compression molded body is lowered. there may be In addition, the fiber length of the composite fiber may be applied by changing the fiber length of the composite fiber according to a product to be manufactured using the composite fiber. And, if the number of crimps is less than 9/inch, the elasticity and bulkiness of the composite fiber may be lowered, and if it exceeds 15/inch, there may be a problem of increasing the occurrence of neps during the carding process when manufacturing the fiber assembly. have.

The composite fiber of the present invention may provide functionality by modifying the surface of the fiber, or a hydrophilic coating layer and/or a hydrophobic coating layer may be formed on the surface of the composite fiber.

The composite fiber of the present invention may have a strength of 3.5 g/d or more, an elongation of 55% or more, an initial modulus of 3.2 g/d or more, a shrinkage ratio of 5.0 to 6.5%, and a number of crimps of 9 to 15 pieces/inch, preferably a strength of 3.70 ~ 4.10 g/d, elongation of 57 ~ 62%, initial modulus of 3.2 ~ 3.8 g / d, shrinkage of 5.4 ~ 6.2%, and may have a number of crimps of 10 ~ 14 / inch.

When the composite fiber of the present invention is a sheath-core type composite fiber, the compression molded article made of the sheath-core type composite fiber has a flexural strength of 5.5 MPa or more when measured according to ASTM D790 at 50% relative humidity and 23°C and a flexural modulus of 430 MPa or more, preferably a flexural strength of 7.4 to 12 MPa and a flexural modulus of 480 to 700 MPa, more preferably a flexural strength of 9.5 to 11.5 MPa and a flexural modulus of 508 to 620 MPa.

In addition, when the composite fiber of the present invention is a sheath-core type composite fiber, the compression molded article made of the sheath-core type composite fiber has a tensile strength of 18.5 when measured according to ASTM D638 at 50% relative humidity and 23°C Mpa or more, preferably, the tensile strength may be 20 to 27 Mpa, more preferably 20.2 to 23.5 Mpa.

Such, the composite fiber of the present invention is a first step of preparing a polyester chip and a crystalline polyolefin chip, respectively; A second step of preparing an unstretched sub-tow by putting the first component resin and the second component resin in which the polyester chip and the crystalline polyolefin chip are melted, respectively, into a composite spinneret and composite spinning, followed by cooling; After stretching the unstretched sub tow, a third step of applying a crimp; and 4 steps of heat-setting and cutting the stretched and crimped sub tow;

The characteristics and types of the polyester chip in the first step are the same as the first component resin described above, and the characteristics and types of the crystalline polyolefin chip are the same as the second component resin described above, and the first component resin and The second component resin is chipped.

The melting of the second step may be performed under 270° C. to 300° C. of the polyester, and 230° C. to 280° C. of the crystalline polyolefin chip.

The two-step composite spinning may be performed under the conditions of a spinning temperature of 260° C. to 290° C. and a winding speed of 400 to 1,300 m/min, preferably 265° C. to 285° C. and a winding speed of 500 to 1,200 m/min. At this time, if the spinning temperature is less than 260 ℃, there may be a problem that the pack (pack) pressure increase and spinning workability is reduced, if the spinning temperature exceeds 290 ℃, there may be a problem in that the physical properties of the composite fiber is reduced. In addition, if the winding speed is less than 500 m/min, the elongation may increase and there may be a problem in that the physical properties of the composite fiber and/or the applied product using the same may be deteriorated. There may be a problem in that the form laminated on the can is non-uniform, thereby reducing the stretching workability.

In addition, the subtow of step 2 may be a sheath-core type monofilament, a side-by-side type monofilament, a sea-island type monofilament, or a split type monofilament.

The three-step stretching may be performed by a general method used in the art, and preferably, the unstretched subtow is stretched 2.5 to 5 times, preferably 3.0 to 4.5 times under 70° C. to 100° C. can do. At this time, if the draw ratio is less than 2.5 times, the elongation may increase and the physical properties of the applied product using the composite fiber may decrease. it's good

And, the crimping of the three steps may be performed by a general crimping method used in the art, and for example, a crimp is formed using a crimp box capable of passing 3,000 de to 8,000 de per 1 mm of the stretched subtow. Crimping can be performed through the process.

In addition, a process of increasing the stability of the sub tow may be additionally performed by performing a heat treatment process on the stretched sub tow before crimping. For a specific example, the surface of the hot drum using a plurality of hot drums It is also possible to heat-treat by contacting for about 5 to 30 seconds to increase the crystallinity of the sub-tow, thereby improving the shrinkage rate and the elastic modulus.

The four-step heat setting can be performed through a general heat setting method used in the art, and for example, after putting the stretched and crimped sub tow into an oven, under 140° C. to 180° C., preferably After that, it can be carried out for 10 to 20 minutes under 140 ℃ ~ 170 ℃. At this time, if the heat setting temperature is less than 140 ℃, there may be a problem that the shrinkage rate of the final composite fiber produced increases, and if it exceeds 180 ℃, the dispersibility of the composite fiber is lowered, the density of the composite fiber of the fiber assembly is lowered, and workability Since there may be a problem of this falling, it is preferable to perform heat setting under the above temperature range.

And, the cutting in step 4 is a process of cutting the heat-set sub-tow so that the composite fiber has an appropriate fiber length depending on the processed product to use the composite fiber, and can be performed by a general cutting method used in the art, It is preferable to perform cutting within the average fiber length of the composite fiber in the range of 3 mm to 120 mm.

Through this manufacturing method, as described above, the composite fiber of the present invention having an average fineness of 4 to 12 de, an average fiber length of 3 to 120 mm, and a number of crimps of 9 to 15 pieces/inch can be manufactured.

By using the composite fiber of the present invention described above, it is possible to manufacture a fiber aggregate such as a nonwoven fabric. In this case, the non-woven fabric may be a dry-laid non-woven fabric, a wet-laid non-woven fabric or an air-laid non-woven fabric, preferably a thermal bonding non-woven fabric, or needle-punching (needle-punching) non-woven fabric. ) may be a dry nonwoven fabric such as a nonwoven fabric.

In addition, after laminating the fiber aggregate in one layer or multiple layers, a compression molded product obtained by compression molding may be manufactured. After making it, it is also possible to manufacture a compression molded article by compression molding.

Hereinafter, the present invention will be described in more detail through examples, but the following examples are not intended to limit the scope of the present invention, which should be construed to aid understanding of the present invention.

[Example]

Example 1: Preparation of sheath-core type composite fiber

A PET chip obtained by chipping a polyethylene terephthalate (PET) resin having an intrinsic viscosity of 0.65 dl/g and a melting point of 252° C. was prepared.

In addition, during differential thermal analysis (DSC) analysis, a PP chip obtained by chipping polypropylene (PP) resin having an enthalpy value of 94 J/g and a melting point of 165° C. required to melt the crystal was prepared.

Next, the PET chip was melted at 290°C, the PP chip was melted at 260°C, and then they were put into a composite spinneret and spun, and then cooled to prepare a sheath-core type unstretched-subtow.

At this time, the composite spinning was performed under the conditions of a spinning temperature of 275° C. and a winding speed of 950 m/min, and then loaded into a can through a take-up process.

Next, the unstretched-subtow was stretched 3.2 times under 85° C., followed by heat treatment at 150° C. for 10 seconds.

Next, the stretched subtow was crimped using a sputtering box.

Next, the drawn and crimped subtow was put into an oven, and then heat-set at 165° C. for 15 minutes to prepare a sheath-core type composite fiber having an average fineness of 7de, an average fiber length of 51 mm, and a number of crimps of 11/inch. . At this time, the cross-sectional area ratio of the sheath and the core was 1:1, the sheath was made of PP resin and the core was made of PET resin.

Examples 2 to 12 and Comparative Examples 1 to 10

It was carried out in the same manner as in Example 1, except that as shown in Tables 1 and 2 below, the PET chip as the core component, the PP chip as the sheath component, the average fineness, the average fiber length, the number of crimps, and the cross-sectional area ratio between the sheath and the core were varied. Each of the sheath-core type composite fibers was prepared, and Examples 2 to 12 and Comparative Examples 1 to 10 were carried out.

division intrinsic viscosity
(dl/g) melting point melting point difference DSC average fineness (de),
Average fiber length (mm)/
Number of Crimps (pcs/inch) Core: sheath
cross-sectional area ratio Example 1 core PET 0.65 252℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 2 core PET 0.65 252℃ 82℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 170℃ 90 J/g Example 3 core PET 0.65 242℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 155℃ 95 J/g Example 4 core PET 0.55 241℃ 78℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 5 core PET 0.90 260℃ 95℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 6 core PET 0.65 252℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:0.7 sheath PP * 165℃ 94 J/g Example 7 core PET 0.65 252℃ 87℃ * 10de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 8 core PET 0.65 252℃ 87℃ * 5de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 9 core PET 0.65 252℃ 87℃ * 7de,
95mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 10 core PET 0.65 252℃ 87℃ * 7de,
25mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 11 core PET 0.65 252℃ 87℃ * 7de,
51mm,
14 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Example 12 core PET 0.65 252℃ 87℃ * 7de,
51mm,
9 pcs/inch 1:1 sheath PP * 165℃ 94 J/g

division intrinsic viscosity
(dl/g) melting point melting point difference DSC average fineness (de),
Average fiber length (mm)/
Number of Crimps (pcs/inch) sheath: core
cross-sectional area ratio Comparative Example 1 core PET 0.65 252℃ 82℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 176℃ 89 J/g Comparative Example 2 core PET 0.65 242℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 148℃ 97 J/g Comparative Example 3 core PET 0.46 240℃ 75℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Comparative Example 4 core PET 1.05 262℃ 97℃ * 7de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Comparative Example 5 core PET 0.65 252℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:0.45 sheath PP * 165℃ 94 J/g Comparative Example 6 core PET 0.65 252℃ 87℃ * 7de,
51mm,
11 pieces/inch 1:1.14 sheath PP * 165℃ 94 J/g Comparative Example 7 core PET 0.65 252℃ 87℃ * 12.6de,
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Comparative Example 8 core PET 0.65 252℃ 87℃ * 3.7de;
51mm,
11 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Comparative Example 9 core PET 0.65 252℃ 87℃ * 7de,
51mm,
16 pieces/inch 1:1 sheath PP * 165℃ 94 J/g Comparative Example 10 core PET 0.65 252℃ 87℃ * 7de,
51mm,
8 pcs/inch 1:1 sheath PP * 165℃ 94 J/g

Experimental example 1: Measurement of properties of composite fibers

The strength, elongation, initial modulus of elasticity, and shrinkage of the sheath-core composite fibers prepared in Examples and Comparative Examples were measured according to the following method, and the results are shown in Table 3 below.

1) How to measure tenacity and elongation

The fiber strength and elongation were measured using an automatic tensile tester (Textechno) at a speed of 50 cm/m and a gripping distance of 50 cm. Strength and elongation are the value (g/de) obtained by dividing the applied load by the denier when the fiber is stretched until it is cut by applying a constant force to the strength, and the value (%) expressed as a percentage of the initial length to the stretched length defined.

2) Initial modulus of elasticity, shrinkage How to measure

The initial modulus of elasticity was measured with a USTER TESTER, and the shrinkage was measured based on Equation 1 below for the change in length of the composite fiber before and after dry heat treatment at 180°C for 20 minutes.

[Equation 1]

Shrinkage (%) = (C-D)/C×100%

In Equation 1, C is the average length of fibers before heat treatment, and D is the average length of fibers after heat treatment.

division burglar
(%) Shinto
(%) initial modulus of elasticity
(g/de) shrinkage
(%) crimp
(pcs/inch) Example 1 3.89 59.2 3.5 5.7 10.8 Example 2 3.92 57.3 3.5 5.8 10.9 Example 3 3.84 59.1 3.6 5.8 10.9 Example 4 3.71 57.4 3.5 5.7 11.2 Example 5 4.08 58.1 3.3 5.7 10.8 Example 6 3.82 58.8 3.4 5.7 11.0 Example 7 3.85 59.9 3.7 5.6 10.9 Example 8 3.92 58.6 3.6 5.8 11.0 Example 9 3.88 59.5 3.6 5.6 11.0 Example 10 3.91 58.3 3.5 6.0 10.8 Example 11 3.82 61.7 3.6 5.7 13.6 Example 12 3.94 57.8 3.4 5.5 10.1 Comparative Example 1 3.77 57.1 3.0 5.7 11.1 Comparative Example 2 no radiation Comparative Example 3 3.45 55.3 3.4 5.8 10.7 Comparative Example 4 4.18 54.2 3.4 5.6 10.9 Comparative Example 5 3.14 48.5 3.6 5.6 11.1 Comparative Example 6 3.58 65.2 3.7 5.4 11.0 Comparative Example 7 no radiation Comparative Example 8 no radiation Comparative Example 9 3.72 58.3 3.5 7.5 16.3 Comparative Example 10 3.82 60.7 3.6 5.1 7.8

Looking at the physical property results of the composite fibers shown in Table 3, in the case of Examples 1 to 12, strength 3.71 ~ 4.08 g / d, elongation 57.3 ~ 61.7%, initial modulus 3.3 ~ 3.6 g / d, shrinkage ratio 5.5 ~ 6.0% and It was shown to have a number of crimps of 9.3 to 13.5 pieces/inch.

On the other hand, in the case of Comparative Example 1 in which the melting point of the sheath component exceeded 170° C., there was a problem that the initial elastic modulus had a low value of less than 3.2 g/d, and in Comparative Example 2, where the melting point of the sheath component was less than 150° C., the spinning was very Due to a poor problem, it was impossible to measure the physical properties of the composite fiber.

In addition, in the case of Comparative Example 3, in which PET having an intrinsic viscosity of more than 1.0 dl/g was introduced as a core component, the strength and elongation were inferior as compared with Examples.

And, in the case of Comparative Example 5, in which the cross-sectional area ratio of the composite fiber to the sheath and the core was 1:0.45, which was less than 1:0.5, there was a problem in that the elongation was very poor.

In addition, in Comparative Example 7, in which the average fineness of the composite fiber was designed to exceed 12 de, and Comparative Example 8, in which the average fineness was less than 4 de, spinning was practically impossible.

And, in the case of Comparative Example 9, in which the number of crimps exceeded 16 pieces/inch, there was a problem in that the number of crimps exceeded 15 pieces/inch and formed too much, and in Comparative Example 10 where the number of crimps was less than 9 pieces/inch, the number of crimps was low there was

production example One : compression molding Produce

By carding using only the composite fiber prepared in Example 1, a needle punching nonwoven fabric having a thickness of 10 mm was prepared.

Next, the nonwoven fabric was subjected to a heat treatment process at 200° C. for 90 seconds, and then cold-compressed to prepare a compression molded article (average thickness of 3 mm).

The average areal density of the prepared compression molded article was 1,230 g/m ² , and the uniformity of the average areal density was 3 CV%.

production example 2 : compression molding Produce

50% by weight of the composite fiber prepared in Example 1, 7 denier, 51mm fiber length, and 50% by weight PET having an intrinsic viscosity of 0.65 dl/g were mixed, and then carded to prepare a 10mm thick needle punching (Needle Punching) nonwoven fabric did.

Next, a compression molded article (average thickness of 3 mm) was prepared by performing a heat treatment process and cold compression in the same manner as in Preparation Example 1.

The average areal density of the prepared compression molded article was 1,250 g/m ² , and the uniformity of the average areal density was 4.6 CV%.

production example 3: compression molding Produce

70% by weight of the composite fiber prepared in Example 1 and 7 denier of PET material having an intrinsic viscosity of 0.65 dl/g and 30% by weight of short fibers with a fiber length of 51mm were mixed with 30% by weight, and then carded and needle punched with a thickness of 10mm (Needle Punching) A nonwoven fabric was prepared.

Next, a compression molded article (average thickness of 3 mm) was prepared by performing a heat treatment process and cold compression in the same manner as in Preparation Example 1.

The average areal density of the prepared compression molded article was 1,210 g/m ² , and the uniformity of the average areal density was 3.8 CV%.

production example 4 ~ production example 14: compression molding Produce

It was prepared in the same manner as in Example 1, except that the composite fibers of Examples 2 to 12 were used instead of the composite fibers of Example 1, and carding was performed to prepare a needle punching nonwoven fabric having a thickness of 10 mm.

Next, the nonwoven fabric was subjected to a heat treatment process at 200° C. for 90 seconds, and then cold-compressed to prepare a compression molded article (average thickness 3 mm), and Preparation Examples 4 to 14 were carried out, respectively (see Table 4 below).

Comparative Preparation Example 1

After mixing with 9 denier, 60% by weight of monotype polypropylene fiber and 40% by weight of glass fiber having a fiber length of 70mm, carding was performed to prepare a 10mm thick needle punching (Needle Punching) nonwoven fabric.

Next, a compression molded article (average thickness of 3 mm) was prepared by performing a heat treatment process and cold compression in the same manner as in Preparation Example 1.

Comparative Preparation Example 2

50 wt% of PET binder fiber with a softening point of 110°C with 4 denier, 51 mm of fiber length and 50 wt% of short PET material with 7 denier, 51 mm fiber length, and intrinsic viscosity of 0.65 dl/g Needle Punching A nonwoven fabric was prepared.

Next, a compression molded article (average thickness of 3 mm) was prepared by performing a heat treatment process and cold compression in the same manner as in Preparation Example 1.

Comparative Preparation Examples 3 to 9: Preparation of compression molded articles

It was prepared in the same manner as in Example 1, but using the composite fiber of Comparative Examples 1 to 10 instead of the composite fiber of Example 1, and carding, to prepare a needle punching nonwoven fabric having a thickness of 10 mm.

Next, the nonwoven fabric was subjected to a heat treatment process at 200° C. for 90 seconds, and then cold-compressed to prepare a compression molded article (average thickness 3 mm), and Comparative Preparation Examples 3 to 9 were performed respectively (see Table 4 below). .

division composite fiber mixed fiber Composite fiber and PET fiber mixture Preparation Example 1 Example 1 * 100% by weight of composite fiber Preparation 2 Example 1 PET short fibers with 7 denier, 51 mm fiber length, and 0.65 dl/g intrinsic viscosity 50% by weight of composite fiber
+
PET short fiber 50% by weight Preparation 3 Example 1 PET short fibers with 7 denier, 51 mm fiber length, and 0.65 dl/g intrinsic viscosity 70% by weight of composite fiber
+
PET short fiber 30% by weight Preparation 4 Example 2 * 100% by weight of composite fiber Preparation 5 Example 3 * 100% by weight of composite fiber Preparation 6 Example 4 * 100% by weight of composite fiber Preparation 7 Example 5 * 100% by weight of composite fiber Preparation 8 Example 6 * 100% by weight of composite fiber Preparation 9 Example 7 * 100% by weight of composite fiber Preparation 10 Example 8 * 100% by weight of composite fiber Preparation 11 Example 9 * 100% by weight of composite fiber Preparation 12 Example 10 * 100% by weight of composite fiber Preparation 13 Example 11 * 100% by weight of composite fiber Preparation 14 Example 12 * 100% by weight of composite fiber Comparative Preparation Example 1 Monotype polypropylene (PP) fiber with 9 denier, 70mm fiber length fiberglass PP fiber 60% by weight
+
Glass fiber 40% by weight Comparative Preparation Example 2 PET binder fiber with 4 denier, 51 mm fiber length and a softening point of 110°C PET short fibers with 7 denier, 51 mm fiber length, and 0.65 dl/g intrinsic viscosity PET binder fiber 50% by weight
+
PET short fiber 50% by weight Comparative Preparation Example 3 Comparative Example 1 * 100% by weight of composite fiber Comparative Preparation Example 4 Comparative Example 3 * 100% by weight of composite fiber Comparative Preparation Example 5 Comparative Example 4 * 100% by weight of composite fiber Comparative Preparation Example 6 Comparative Example 5 * 100% by weight of composite fiber Comparative Preparation Example 7 Comparative Example 6 * 100% by weight of composite fiber Comparative Preparation Example 8 Comparative Example 9 * 100% by weight of composite fiber Comparative Preparation Example 9 Comparative Example 10 * 100% by weight of composite fiber

Experimental Example 1: SEM measurement of compression molded articles

SEM photographs of the cut surfaces of the compression molded articles prepared in Preparation Example 1, Preparation Example 2 and Preparation Example 3 are shown in FIGS. 1 to 3 in order, respectively.

Looking at the SEM measurement photo of FIG. 1, in the case of the compression molded article of the present invention, while the fibers are densely formed, in the case of Preparation Examples 2 and 3, looking at FIGS. was low

Experimental Example 2: Measurement of shape stability of compression molded articles

1) Form stability according to temperature

After the compression molded articles prepared in Preparation Example 1, Comparative Preparation Example 1 and Comparative Preparation Example 2 were put into a hot air dryer, a change in shape after aging was confirmed for 1 hour under a load of 80 g applied, and the results are shown in FIG. 4 .

4, in the case of the compression molded article of Preparation Example 1, it was confirmed that the shape stability was excellent even at 100 °C and 110 °C, whereas, in the case of Comparative Preparation Examples 1 and 2, there was a problem that the shape stability was lowered from 100 °C. .

2) Measurement of shape stability after aging in heat-resistant environment

After the compression molded articles prepared in Preparation Example 1, Comparative Preparation Example 1 and Comparative Preparation Example 2 were left in a heat-resistant environment, the external force was removed and the shape stability was measured after 72 hours at 80°C, and the results are shown in Fig. 5 is shown.

Referring to FIG. 5, in the case of Preparation Example 1, there was little change in shape, but in Comparative Preparation Example 1, it was greatly bent, and Comparative Preparation Example 2 also showed a tendency to bend while slightly curling the tip.

Through the measurement of shape stability, it was confirmed that the shape stability of the compression molded article prepared from the composite fiber of the present invention was very good.

Experimental example 3: compression molding The tensile strength, modulus measurement

Tensile strength, flexural strength, and flexural modulus of the compression molded articles prepared in Preparation Examples 1 to 14 and Comparative Preparation Examples 1 to 12 were measured, and the results are shown in Table 5 below, respectively.

At this time, the tensile strength was measured according to ASTM D 638, and the modulus of flexural strength and flexural modulus was measured according to ASTM D 790.

division The tensile strength
(Mpa) flexural strength
(Mpa) flexural modulus
(Mpa) Preparation Example 1 21.3 9.7 542 Preparation 2 18.5 5.7 436 Preparation 3 20.6 7.4 480 Preparation 4 20.8 9.6 537 Preparation 5 21.5 9.4 518 Preparation 6 20.3 9.2 495 Preparation 7 20.4 10.7 583 Preparation 8 20.7 9.1 522 Preparation 9 20.7 10.1 531 Preparation 10 21.1 9.5 508 Preparation 11 23.1 9.3 511 Preparation 12 20.4 9.5 502 Preparation 13 20.4 10.0 545 Preparation 14 21.2 9.2 551 Comparative Preparation Example 1 9.5 3.2 316 Comparative Preparation Example 2 9.0 2.8 125 Comparative Preparation Example 3 20.1 8.5 471 Comparative Preparation Example 4 20.4 7.7 448 Comparative Preparation Example 5 18.8 9.8 490 Comparative Preparation Example 6 19.7 5.9 411 Comparative Preparation Example 7 19.4 7.4 420 Comparative Preparation Example 8 18.6 9.4 483 Comparative Preparation Example 9 18.9 9.5 408

Looking at Table 5, it was confirmed that the compression molded articles of Preparation Examples 1 to 14 were overall superior in tensile strength and modulus than Comparative Preparation Examples 1 and 2, and Preparation Example 1 using the fibers for the compression molded article alone produced PET fibers. Compared to Preparation Examples 2 to 3, which were mixed and used, relatively excellent mechanical properties were obtained.

And, in the case of Comparative Preparation Example 3, there was a problem that the flexural strength was somewhat lowered and the workability was lowered. And, in the case of Comparative Preparation Example 4, the flexural modulus showed poor results.

In addition, in the case of Comparative Preparation Example 5, although the flexural strength was excellent, the tensile strength was also slightly lowered. In the case of Comparative Preparation Example 6 and Comparative Preparation Example 7, there was a problem that the flexural strength and the flexural modulus were too low.

In addition, in Comparative Preparation Example 8, the number of crimps of the composite fibers used was high, so there was a problem that neps were generated. In Comparative Preparation Example 9, the number of crimps of the composite fibers used was too low, resulting in a low flexural modulus. .

Through the above Examples and Experimental Examples, it was confirmed that the composite fiber of the present invention has excellent mechanical properties, and has sound absorption/sound dispersibility and water absorption/water dispersibility. It is expected that the composite fiber of the present invention can be manufactured into a fiber aggregate such as a nonwoven fabric, or the fiber aggregate is compressed to provide various application products, for example, building interior and exterior materials / civil engineering materials / airplanes, ships It can be applied as interior and exterior materials of transportation means / sanitary materials such as diapers, sanitary napkins and masks / filters such as air filters and liquid filters.

Claims (14)

a first component resin having an intrinsic viscosity of 0.50 to 1.00 dl/g and a melting point of 240 to 280°C; and a second component resin having a melting point of 150 to 170° C.; a sheath-core type composite fiber comprising;
In the sheath-core type composite fiber, the cross-sectional area ratio of the core composed of the first component resin and the sheath composed of the second component resin is 1: 0.5 to 1,
The first component resin is a poly containing at least one selected from polyethylene terephthalate (PET) resin, polybutylene terephthalene (PBT) resin, polytrimethylene terephthalate (PTT) resin, and polyethylene naphthalate (PEN) resin. containing an ester resin,
The second component resin includes a crystalline polyolefin resin comprising at least one selected from polypropylene (PP) resin and polyethylene (PE) having a melting point of 150°C to 170°C,
Composite fiber for compression molded article, characterized in that the difference in melting point temperature between the first component resin and the second component resin is 30°C to 100°C.
The composite fiber for a compression molded article according to claim 1, wherein the crystalline polyolefin resin has an enthalpy value of 40 to 120J/g required to melt the crystals during differential thermal analysis (DSC) analysis.
delete The method of claim 1, wherein the PET resin is
A composite fiber for a compression molded article, comprising a polymer obtained by polymerizing terephthalic acid and diol in a molar ratio of 1:0.95 to 1.20.
delete delete delete [Claim 5] The method according to any one of claims 1, 2 and 4, wherein the fibers for compression molded products have an average fineness of 4 to 12 de, an average fiber length of 3 to 120 mm, and a number of crimps of 9 to 15/inch. Composite fiber for compression molded article, characterized in that.
delete Step 1 of preparing a polyester chip and a crystalline polyolefin chip, respectively;
A second step of preparing an unstretched sub-tow by putting the first component resin and the second component resin in which the polyester chip and the crystalline polyolefin chip are melted, respectively, into a composite spinneret and composite spinning, followed by cooling;
After stretching the unstretched sub tow, a third step of applying a crimp; and
4 steps of heat-setting and cutting the stretched and crimped sub tow; manufactured by performing a process comprising:
The subtow is a sheath-core monofilament,
The melting of the second step is carried out under 270 ° C. to 300 ° C. for the polyester chip, and 230 ° C. to 280 ° C. for the crystalline polyolefin chip.
The first component resin constitutes a core, and the second component resin constitutes a sheath,
The first component resin has an intrinsic viscosity of 0.50 to 1.00 dl/g and a melting point of 240 to 280° C., and the first component resin is polyethylene terephthalate (PET) resin, polybutylene terephthalene (PBT) resin, polytrimethylene tere. A polyester resin comprising at least one selected from a phthalate (PTT) resin and a polyethylene naphthalate (PEN) resin,
The second component resin has a melting point of 150° C. to 170° C., and the second component resin comprises a crystalline polyolefin resin comprising at least one selected from polypropylene (PP) resin and polyethylene (PE). A method for manufacturing a composite fiber for a compression molded article.
11. The method of claim 10, wherein the composite spinning in the second step is performed under the conditions of a spinning temperature of 260° C. to 290° C. and a winding speed of 400 to 1,300 m/min.
A fiber assembly for a compression molded article, characterized in that it comprises the composite fiber of claim 8.
A nonwoven fabric for a compression molded article, comprising the composite fiber for a compression molded article of claim 8.
The nonwoven fabric for compression molded article according to claim 13, wherein the nonwoven fabric is a dry-laid nonwoven fabric, a wet-laid nonwoven fabric, or an air-laid nonwoven fabric.

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