KR20190087715A - Automotive interior material comprising low melting polyester resin, preparation method thereof - Google Patents

Abstract

The present invention relates to an automobile interior material comprising a low melting point polyester resin fiber layer and a method for manufacturing the same. The present invention provides the automobile interior material which realizes excellent processability without deteriorating physical properties such as strength and durability, and also has excellent price competitiveness. The automobile interior material according to the present invention includes a fiber layer comprising a first fiber and a second fiber.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automobile interior material comprising a low melting point polyester resin, and a method of manufacturing the same. BACKGROUND ART < RTI ID = 0.0 >

The present invention relates to an automobile interior material comprising a low melting point polyester resin and a method for producing the same.

In order to be applied as an automobile interior material, characteristics such as light weight, buffering property, heat insulating property, formability, high strength and energy saving are required. Low-melting fibers are often used as automotive interior materials. The low melting point resin is an adhesive material that melts at a temperature of 100 to 200 ° C lower than that of a general polyester fiber melting at 265 ° C or more, and is an eco-friendly material that does not require a chemical adhesive. By attaching a base material layer made of a thermoplastic resin, a flexible polyurethane foam layer, and a layer made of a fibrous layer to the low melting point resin fiber layer as a laminated material, the durability can be improved and the manufacturing cost per unit volume can be reduced. An automotive interior material having a small dimensional change rate and excellent sound absorption rate can be obtained.

However, when the flexible polyurethane foam layer is used for the laminate, the thickness of the automobile interior material is increased to satisfy the required properties of the automobile interior material, and since a large amount of the adhesive is used for compositing the other components in the manufacturing process, , There is a disadvantage that it can not be recycled.

Therefore, there is a need for an automobile interior material which is excellent in workability and can reduce manufacturing cost.

U.S. Patent No. 4,129,675 U.S. Patent No. 4,065,439

In order to solve such a problem, an object of the present invention is to provide an automobile interior material having excellent workability and excellent price competitiveness.

In order to achieve the above object, the present invention provides, in one embodiment,

And a fiber layer comprising a first fiber and a second fiber,

Wherein the first fiber comprises:

A core portion formed of a polyester resin having a melting point higher than 250 캜, and

A sheath portion formed of a polyester resin having a melting point of 180 ° C to 250 ° C or a softening point of 100 ° C to 150 ° C,

A composite fiber having an average length of 3 to 100 mm,

Wherein the second fiber is a fiber formed of a polyester resin having a melting point higher than 250 캜.

In addition, the present invention, in one embodiment,

Thermoforming a fiber layer comprising a first fiber and a second fiber in a temperature range of 80 to 200 < 0 > C,

The first fiber is a composite fiber comprising a core portion formed of a polyester resin having a melting point higher than 250 캜 and a sheath portion formed of a polyester resin having a melting point of 180 캜 to 250 캜 or a softening point of 100 캜 to 150 캜 ,

Wherein the second fiber is formed of a polyester resin having a melting point higher than 250 ° C.

Since the automobile interior material according to the present invention uses a low-melting-point polyester resin, excellent workability can be realized without deteriorating physical properties such as strength and durability.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the present invention, the terms "comprising" or "having ", and the like, specify that the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

In the present invention, the term "weight portion" means the weight ratio between the components

Herein, in the present invention, the term "molar part" means a molar fraction of each component.

Further, in the present invention, the "melting point" means the temperature at which the solid phase resin begins to melt in a liquid phase.

In addition, the term "polymer" in the present invention means an oligomer and / or a polymer obtained by performing a polymerization reaction of a monomer or a compound containing a polymerizable reactive group.

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

The present invention provides an automobile interior material comprising a low melting point polyester resin fiber layer.

In one embodiment, the automotive interiors according to the present invention comprise a fibrous layer comprising a first fiber and a second fiber.

The first fiber is a core-sheath structure, and the sheath portion of the first fiber is a low melting point resin. Specifically, the first fiber has a core portion formed of a polyester resin having a melting point higher than 250 캜, and a sheath portion formed of a polyester resin having a melting point of 180 캜 to 250 캜 or a softening point of 100 캜 to 150 캜 to be.

And the second fiber is formed of a polyester resin having a melting point higher than 250 캜. In the fibrous layer, the first fiber is a fiber formed of a polyester resin having a melting point of 180 캜 to 250 캜 or a softening point of 100 캜 to 150 캜.

In the present invention, the expression 'low melting point' to 'high melting point' can be interpreted in a relative sense. In the present invention, in the first fiber, the sheath portion constituting the outer portion of the fiber is formed of a low melting point resin, and the inner core portion is formed of a high melting point resin. The second fiber is a polyester resin fiber having a melting point higher than 250 캜, and is also referred to as a high-melting-point polyester resin fiber in a relative sense.

The fibrous layer is a mixture of the first fiber and the second fiber. The mixing ratio of the first fiber to the second fiber may be controlled in a weight ratio of 3.5: 6.5 to 7: 3. In some cases, the mixing ratio may range from 4: 6 to 6: 4. By mixing and using heterogeneous fibers, in particular, by using composite fibers having a low melting point on the surface (sheath portion) of the fibers, the bonding strength between the fibers can be enhanced and the strength can be reinforced at the same time. For example, the high-melting-point polyester resin has a melting point higher than 250 ° C, specifically, 251 to 260 ° C. The high-melting-point polyester resin is commercially available. For example, a product (product name: SD, Semi-dull chip) of Huvis Corporation can be used.

Specifically, the shape, the thickness, and the lamination structure of the fibrous layer are not particularly limited. For example, the fibrous layer is a partially fused form between the fibers forming the fibrous layer. In the partially fused form between the fibers, heat and / or pressure is applied during the process of forming the fiber layer by thermoforming, and the fibers are partially fused to each other in the process. Since the fiber layer according to the present invention includes the low-temperature fusion-bondable fiber made of a polyester resin having a low melting point, it can form a partial fusion-bonded form between the fibers through low temperature molding.

The first fiber forming the fibrous layer is in the form of a short fiber, specifically, in the form of a staple fiber having an average length of 3 to 100 mm. The average length of the first fibers may range, for example, from 5 to 80 mm or from 50 to 70 mm. By forming the fibrous layer by using the first fiber of the short fiber form, the morphological stability of the fibrous layer and the like can be improved. The second fiber is not particularly limited, but may be applied in a short fiber form. The average length of the second fibers is controllable in the same range as that of the first fibers.

As yet another example, the fibrous layer may further comprise a functional additive component. For example, the fiber layer may further include glass fibers in an amount of 5 parts by weight or less, or 2 parts by weight or less, based on 100 parts by weight of the whole fiber layer. By including glass fibers, heat resistance can be improved. However, the glass fibers may be desorbed during processing, which causes the work environment to be deteriorated. Therefore, the automobile interior material according to the present invention may be a structure substantially not containing glass fibers. If necessary, a small amount of a flame retardant, a thickener, an inorganic filler, etc. may be added.

The automobile interior material according to the present invention realizes excellent tensile strength and / or low combustibility.

As an example, the tensile strength may be 10 to 150 MPa, for example 10 to 130 MPa, 30 to 100 MPa or 40 to 100 MPa, based on ASTM D 638. By satisfying the tensile strength within the above range, the automotive interior material according to the present invention can realize excellent durability.

In addition, the flame resistance may be 80 or less based on KS M ISO 9772. Specifically, the automobile interior material according to the present invention has flame-retardant or non-flammable properties, which can reduce fire risk in the future.

The automobile interior material according to the present invention has excellent durability. Specifically, the automobile interior material is left to stand at a temperature of 90 ± 1 ° C for 24 hours; And a step of allowing to stand for 24 hours at a temperature of 50 ± 1 ° C and a relative humidity of 90%, the following equation (1) can be satisfied.

[Equation 1]

| V ₁ -V ₀ | / V ₀ x 100? 5%

In the above equation (1)

V ₀ is the volume (mm ³ ) of the vehicle interior material before exposure to the harsh conditions,

V ₁ is the volume (mm ³ ) of the automotive interior material after exposure to the harsh conditions.

Specifically, the dimensional change rate of the manufactured automobile interior material samples before and after the severe condition was measured. This is a measurement value corresponding to the long-term dimensional change rate after applying the automobile interior material to the vehicle. For example, the volume may mean a value calculated by multiplying the length of each of the lengths, widths, and thicknesses of the automobile interior material. For example, the rate of dimensional change of the formula (1) may range from 0.01 to 5%, from 0.01 to 3%, or from 0.01 to 1%. By satisfying the value of the expression (1) in the above range, it can be seen that the shape of the automobile interior material according to the present invention does not change even in long-term use in an environment of severe temperature change.

At this time, if the above formula (1) is more than 5%, it may mean that peeling, parts, sagging, discoloration or deformation easily occur in the automobile interior material.

Also, the automobile interior material may have a sound absorption coefficient of 0.4 NRC or more measured according to KS F 2805, and a transmission loss value measured according to KS F 2080 of 10 dB or more. For example, the sound absorption rate may range from 0.4 to 1 NRC or 0.4 to 0.6 NRC, and the difference tone may range from 10 to 30 dB or 15 to 25 dB. As described above, the automobile interior material according to the present invention can realize sound absorption and sound insulation at a high level at the same time, and can effectively sound and sound the noise in the vehicle and the outside.

Hereinafter, the first fiber forming the fibrous layer according to the present invention will be described in more detail.

The sheath portion of the first fiber includes a polyester resin containing a repeating unit represented by the following general formulas (1) and (2). In this case, the core portion of the first fiber may have a structure including a repeating unit represented by the following formula (1).

[Chemical Formula 1]

(2)

In the above formulas (1) and (2)

m and n represent mole fractions of the repeating units contained in the polyester resin,

n is 0.05 to 0.5 based on m + n = 1.

And the sheath portion of the first fiber is a low-melting-point polyester resin. The low-melting-point polyester resin may have a structure containing repeating units represented by formulas (1) and (2). The repeating unit represented by the formula (1) represents a repeating unit of polyethylene terephthalate (PET), and the repeating unit represented by the formula (2) improves the tear characteristics of a polyester resin containing a polyethylene terephthalate (PET) repeating unit Function. Specifically, the repeating unit represented by the formula (2) includes a methylene group (-CH ₃ ) as a side chain in a propylene chain bonded to terephthalate, thereby securing a space in which the main chain of the polymerized resin can rotate, It is possible to lower the melting point (Tm) by inducing a decrease in crystallinity of the resin. This may have the same effect as in the case of using isophthalic acid (IPA) containing an asymmetric aromatic ring in order to lower the melting point (Tm) of the crystalline polyester resin.

At this time, the low-melting-point polyester resin may contain, as a main repeating unit, a repeating unit represented by the following formula (2), which decreases the melting point (Tm) of the resin together with the repeating unit represented by the formula (1) Specifically, when the molar fraction of the total resin is 1, the low melting point polyester resin of the present invention may contain 0.5 to 1 as repeating units represented by the formulas (1) and (2), specifically 0.55 to 1; 0.6 to 1; 0.7 to 1; 0.8 to 1; 0.5 to 0.9; 0.5 to 0.85; 0.5 to 0.7; Or from 0.6 to 0.95.

The amount of the repeating unit represented by the formula (2) contained in the low melting point polyester resin may be 0.05 to 0.5 when the total fraction including the repeating unit represented by the formula (1) is 1 (m + n = 1) 0.05 to 0.4, 0.1 to 0.4, 0.15 to 0.35; Or from 0.2 to 0.3.

The melting point (Tm) of the low melting point polyester resin may be 180 ° C to 250 ° C, or the melting point may not be present. Specifically, the melting point (Tm) is 180 占 폚 to 250 占 폚; 185 DEG C to 245 DEG C; 190 DEG C to 240 DEG C; 180 DEG C to 200 DEG C; 200 < 0 > C to 230 [deg.] C or 195 [deg.] C to 230 [deg.] C or absent.

In addition, the softening point of the low melting point polyester resin may be 100 ° C to 150 ° C, specifically, 100 ° C to 130 ° C, 118 ° C to 128 ° C; 120 DEG C to 125 DEG C; 121 DEG C to 124 DEG C; 124 DEG C to 128 DEG C or 119 DEG C to 126 DEG C. [

Further, the low melting point polyester resin may have a glass transition temperature (Tg) of 50 DEG C or more. Specifically, the glass transition temperature may be from 50 캜 to 80 캜, and more specifically from 61 캜 to 69 캜, 60 캜 to 65 캜, 63 캜 to 67 캜, 61 캜 to 63 캜, 63 캜 to 65 캜, 65 Deg.] C to 67 [deg.] C or 62 [deg.] C to 67 [deg.] C.

The low melting point polyester resin may have an intrinsic viscosity (I.V) of 0.5 dl / g to 0.75 dl / g. Specifically, the intrinsic viscosity (I.V) is from 0.6 dl / g to 0.65 dl / g; 0.65 dl / g to 0.70 dl / g; 0.64 dl / g to 0.69 dl / g; 0.65 dl / g to 0.68 dl / g; 0.67 dl / g to 0.75 dl / g; 0.69 dl / g to 0.72 dl / g; 0.7 dl / g to 0.75 dl / g; Or from 0.63 dl / g to 0.67 dl / g.

The melting point (Tm), the softening point, and the glass transition temperature (Tg) of the low melting point polyester resin according to the present invention can be controlled within the above range by including the repeating unit represented by the general formula (2) Excellent adhesion can be exhibited.

On the other hand, the low melting point polyester resin forming the sheath portion of the first fiber may further include a repeating unit represented by the following formula (3) together with the repeating units represented by the formulas (1) and (2).

(3)

In Formula 3,

X is a 2-methylpropylene group, an ethylene group or an oxydiethylene group,

r is the mole fraction of the repeating units contained in the low melting point polyester resin, and is not more than 0.3.

Specifically, in Formula 3, r may be 0.25 or less, 0.2 or less, 0.15 or less, or 0.1 or less.

By using the repeating units represented by the above-mentioned general formula (3) together, it is possible to remarkably reduce the content of the cyclic compound having a polymerization degree of from 2 to 3, for example,

As one example, the content of the cyclic compound having a degree of polymerization of 2 to 3 in the low melting point polyester resin according to the present invention is remarkably decreased and can be contained in an amount of 1% by weight based on the total resin weight. Specifically, 0.5% by weight or less, 0.4% by weight or less, 0.3% by weight or less, or 0.2% by weight or less based on the total weight of the composition.

The automobile interior material according to the present invention may include a resin foam layer and may have a structure in which the above-described fiber layers are laminated on one surface or both surfaces of the resin foam layer.

Specifically, the automobile interior material comprises a polyester resin foam layer; And a polyester resin fiber layer formed on both sides of the polyester resin foam layer.

The polyester resin foam layer may be in the form of a foam board or a foam sheet. Specifically, the automobile interior material is a structure in which a polyester resin fiber layer is laminated on both sides of a polyester resin foam sheet.

For example, the polyester resin foam layer may be a polyethylene terephthalate (PET) foam sheet, and the fiber layer may be a polyethylene terephthalate fiber. By forming various components or all components constituting the laminate from a PET series resin, it is possible to improve the interlaminar bondability and to regenerate the resin from the environmental viewpoint.

In one embodiment, the production process of the low melting point polyester resin will be described in detail as follows.

There is provided a process for producing a low melting point polyester resin comprising a step of performing an ester exchange reaction of a mixture comprising polyethylene terephthalate (PET) and 2-methyl-1,3-propanediol.

The method for producing a low melting point polyester resin according to the present invention is a method for producing a low melting point polyester resin comprising an aromatic dicarboxylic acid such as phthlic acid, terephthalic acid, isophthalic acid (IPA) and the like; A polyester polymer obtained by polymerizing a diol compound such as ethylene glycol (EG), propylene glycol (PG), diethylene glycol (DEG), dipropylene glycol (DPG) Methyl-1,3-propanediol may be mixed with the mixture, followed by conducting an ester exchange reaction of the mixture according to a method commonly used in the art.

As one example, the low-melting-point polyester resin is obtained by mixing 2-methyl-1,3-propanediol with a polyethylene terephthalate oligomer (PET oligomer), adding an ester exchange reaction catalyst, Exchange reaction.

At this time, the 2-methyl-1,3-propanediol may be mixed in a proportion of 5 to 50 parts by mol per 100 parts by mol of polyethylene terephthalate (PET) which is a polyester polymer. Specifically, it is used in an amount of 5 to 40 molar parts relative to 100 molar parts of polyethylene terephthalate (PET); 10 to 30 molar parts; 20 to 40 molar parts; 25 molar to 50 molar parts; Or from 30 moles to 50 moles. In the present invention, by adjusting the content of the additive for low-melting-point resin to the above range, the melting point of the resin is not sufficiently lowered due to the low content of the additive, or the crystallinity exceeds the critical point at which the crystallinity of the resin is reduced due to excessive additives Can be prevented from increasing.

Further, the mixture in which the transesterification reaction is carried out may further comprise at least one of isophthalic acid (IPA) and diethylene glycol (DEG) together with polyethylene terephthalate (PET) and 2-methyl- . Specifically, the mixture may contain polyethylene terephthalate (PET), 2-methyl-1,3-propanediol and diethylene glycol (DEG), or may contain polyethylene terephthalate (PET) , Diethylene glycol (DEG) and isophthalic acid (IPA).

The isophthalic acid (IPA) may be contained in an amount of 30 moles or less based on 100 moles of polyethylene terephthalate (PET). More specifically, not more than 25 moles, not more than 20 moles, not more than 15 moles, or not more than 10 moles, based on 100 moles of polyethylene terephthalate (PET). The content of the isophthalic acid (IPA) is 0.1 mol or more or 1 mol or more, or does not contain isophthalic acid. For example, 0.5 to 0.001 part by mole of isophthalic acid (IPA) may be contained.

The polyethylene glycol (DEG) may be contained in an amount of 1 to 20 moles relative to 100 moles of polyethylene terephthalate (PET). Specifically, the amount of the diethylene glycol (DEG) may be 5 to 15 moles per 100 moles of polyethylene terephthalate 15 moles, 15 moles to 20 moles, 12 moles to 18 moles, 13 moles to 17 moles, or 14 moles to 16 moles.

The present invention can reduce the production cost by controlling the content of isophthalic acid (IPA) within the above range, and can also minimize the content of the cyclic compound having a polymerization degree of 2 to 3 in the low melting point polyester resin to be produced, By controlling the content of the DEG in the above range, it is possible to suppress the decrease of the glass transition temperature (Tg) remarkably while the melting point (Tm) of the resin is optimized, thereby preventing the problem of aging caused during spinning.

The automobile interior material according to the present invention may have a structure in which a resin foam layer is laminated on one side or both sides of the above-described fiber layer. Alternatively, the automobile interior material may comprise a polyester resin foam layer; And a polyester resin fiber layer formed on one side or both sides of the polyester resin foam layer.

The foamed polyester resin foam layer has a flexural modulus of 400 to 30,000 (measured at a flexural load of 5 mm / min at a fixing rate of 100 mm as a supporting space of a specimen, according to ASTM D 790) MPa range, or from 700 to 2,000 MPa. By providing excellent bending elasticity in the present invention, sagging phenomenon can be prevented when applied to an automobile interior material, and excellent durability can be imparted.

The polyester resin foam layer may be a polyethylene terephthalate (PET) foam sheet.

By forming various components or all components constituting the laminate structure with a resin of PET series, it is possible to improve the interlayer bonding property and to easily regenerate the resin from the environmental viewpoint.

In addition, the mass per unit area of the automobile interior material may range from 500 to 1100 g / m ^{2 on} average. For example, the mass per unit area of the automotive interiors may be from 550 to 1000 g / m ² , from 600 to 1000 1100 g / m ^2, or from 800 to 900 1100 g / m ² . By satisfying the mass per unit area in the above range, it can be confirmed that the automobile interior material according to the present invention is lightweight.

The automobile interior material according to the present invention can be used variously in interior parts or interior of an automobile. Specifically, the automobile interior material is applicable as a trunk lining material, a tray package, a floor under cover or a car mat. For example, when the interior material according to the present invention is used as a floor under cover of an automobile, it can be installed at the bottom of an engine, a transmission, or a cooling fan to effectively protect the engine and the transmission from impacts externally applied thereto.

Further, the present invention provides a method for manufacturing the automobile interior material described above.

As one example, the method for manufacturing the automobile interior material includes thermoforming the fiber layer including the first fiber and the second fiber at a temperature range of 80 to 200 占 폚.

The first fiber is a composite fiber comprising a core portion formed of a polyester resin having a melting point higher than 250 캜 and a sheath portion formed of a polyester resin having a melting point of 180 캜 to 250 캜 or a softening point of 100 캜 to 150 캜 , And the second fiber is formed of a polyester resin having a melting point higher than 250 캜.

Specifically, the sheath portion of the first fiber includes repeating units represented by the following formulas (1) and (2).

[Chemical Formula 1]

(2)

In the above formulas (1) and (2)

m and n represent mole fractions of the repeating units contained in the low melting point polyester resin,

n is 0.05 to 0.5 based on m + n = 1.

The first fiber forming the fibrous layer is in the form of a short fiber, specifically, in the form of a staple fiber having an average length of 3 to 100 mm. The average length of the first fibers may range, for example, from 5 to 80 mm or from 50 to 70 mm. By forming the fibrous layer by using the first fiber of the short fiber form, the morphological stability of the fibrous layer and the like can be improved. The second fiber is not particularly limited, but may be applied in a short fiber form. The average length of the second fibers is controllable in the same range as that of the first fibers.

The step of thermoforming can be controlled in a range in which the low melting point polyester resin as the sheath portion of the first fiber is partially melted. For example, the thermoforming step may be performed at a temperature range of 100 to 150 ° C. Further, in the step of thermoforming, a pressure higher than atmospheric pressure is applied. It can be molded into a desired shape while simultaneously applying heat and pressure. The range of the applied pressure is not particularly limited, and may be, for example, 1.5 to 10 atm, and 2 to 5 atm.

Before or after the thermoforming step, a polyester resin foam layer; And laminating the fiber layer on one side or both sides of the polyester resin foam layer.

In one embodiment, after the thermoforming step, a first polyester resin fiber layer; A polyester resin foam layer; And a second polyester resin fiber layer in this order. In the present invention, by introducing a polyester resin foam layer, it is possible to supplement the sound insulation and strength. The polyester resin foam may be in the form of a board or a sheet.

Optionally, before the thermoforming step, a first polyester resin fiber layer; A polyester resin foam layer; And a second polyester resin fiber layer are sequentially laminated to form a laminate. In this case, in the thermoforming step, the first polyester resin fiber layer; A polyester resin foam layer; And the second polyester resin fiber layer is thermally formed to form a desired shape.

A first polyester resin fiber layer; A polyester resin foam layer; And a second polyester resin fiber layer are laminated in this order. Although the structure in which the polyester resin foam layer is exposed to the outer layer is not excluded, in this case, the sound absorption property may be deteriorated. The first and second polyester resin fiber layers correspond to the polyester resin fiber layers described above. The polyester resin foam layer is also as described above.

For example, the first and second polyester resin fiber layers and the polyester resin foam layer may all be formed of PET (polyethylene terephthalate) resin.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples.

However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the present invention is not limited to the following Examples and Experimental Examples.

Manufacturing example  1 to 25: Production of conjugated fiber

Terephthalic acid (TPA) and isophthalic acid (IPA), which are acidic components, are added to the ester reaction tank. Methylene-1,3-propanediol (MPD), ethylene glycol (EG) and diethylene glycol (DEG) were mixed in the molar ratio shown in Table 1 below, The esterification reaction was carried out at 250 ± 5 ° C after the addition of the catalyst. When the esterification reaction rate reached about 96%, the esterification reaction was terminated and a condensation polymerization catalyst was added, and the condensation polymerization reaction was carried out so that the final temperature and vacuum pressure in the reaction vessel were 280 ± 5 ° C. and 0.1 mmHg, respectively. After the viscosity of the resin is converted to the stirrer torque meter, the viscosity of the resin can be adjusted in this manner by terminating the condensation polymerization at the desired viscosity. A low melting point resin was prepared.

The decompression was gradually broken, the pressure was applied, discharged out of the reactor, cooled, and cut into pellets to measure the resin properties. At the same time, the resin is mixed and dispersed in a sheath-core form, the resin is flowed to a sheath portion, and the polyethylene terephthalate is flowed to the core portion, Lt; / RTI > fiber was prepared. The first fibers were cut to an average length of 50 to 60 mm.

The contents of the components added to the respective examples were varied as shown in Table 1 below.

Example No. Acid content (mol%) Diol component (mol%) IPA TPA MPD DEG EG One 0 100 40 0 60 2 15 85 30 0 70 4 5 95 30 0 70 5 0 100 30 0 70 6 0 100 30 15 55 7 0 100 25 15 60 8 10 90 20 0 80 9 10 90 20 10 70 10 10 90 20 15 65 11 0 100 20 0 80 12 0 100 20 20 60 13 0 100 15 25 60 14 20 80 10 15 75 15 0 100 10 0 90 16 40 60 0 0 100 17 35 65 0 10 90 18 30 70 0 0 100 19 30 70 0 15 85 20 20 80 0 0 100 21 20 80 0 15 85 22 20 80 0 20 80 23 15 85 0 25 75 24 10 90 0 0 100 25 0 100 0 30 70

Experimental Example  One.

The properties of the samples prepared in Preparation Examples 1 to 25 were evaluated by the following items. The evaluation results are shown in Table 2 below.

(1) Determination of content of cyclic compounds

10 mg of each polyester resin is injected into a Pyrex tube having a diameter of 5 mm and a length of 20 cm in a solvent of trifluoroacetic acid (TFA) to have a height of about 5 cm. ¹ H-NMR spectra were measured using Nuclear Magnetic Resonance (NMR, Bruker). From the measured results, the content of the cyclic compound having a degree of polymerization of 2 to 3 remaining in the low melting point resin was derived.

(2) Softening temperature , Melting point ( Tm ) And glass transition temperature ( Tg ) Measure

The melting point (Tm) and the glass transition temperature (Tg) of the low melting point polyester resin were measured using a differential scanning calorimeter (Perkin Elmer, DSC-7). When the heat absorption peak was not observed during the measurement of the melting point (Tm) The softening behavior was measured in a TMA mode using a dynamic mechanical analyzer (DMA-7, Perkin Elmer).

(3) Intrinsic viscosity ( I.V ) And melt viscosity measurement

The polyester resin was dissolved in a solution of phenol and tetrachloroethane in a weight ratio of 1: 1 at a concentration of 0.5 wt%, respectively, and intrinsic viscosity (I.V) was measured at 35 캜 using a Ube load viscometer. Further, melt viscosity was measured using a conventional method.

Example No. Ring compound
[wt%] Softening temperature
[° C] Tm
[° C] Tg
[° C] IV
(dl / g) Melting point
(Poise) One 0 120 - 70.4 0.581 913.0 2 0.25 110 - 68.0 0.581 853.0 4 0 - 178 68.0 0.580 847.0 5 0 - 196.3 72.1 0.582 851.0 6 0 118 - 60.8 0.580 864.0 7 0 121 63.5 0.582 847.0 8 0.2 - 181 70.0 0.582 811.0 9 0.19 120 - 62.0 0.579 815.0 10 0.17 115 - 60.7 0.582 831.0 11 0 - 210.5 74.6 0.583 818.0 12 0 129 - 61.4 0.581 811.0 13 0 - 176 55.7 0.581 781.0 14 0.36 125 - 60.5 0.579 754.0 15 0 - 235.3 76.5 0.581 736.0 16 0.86 128 - 70.1 0.580 673.0 17 0.73 108 - 67.1 0.581 654.0 18 0.73 - 195.2 71.0 0.582 687.0 19 0.53 112 - 61.0 0.579 659.0 20 0.41 - 208.6 71.6 0.580 677.0 21 0.39 - 178 63.0 0.581 697.0 22 0.32 119 - 63.0 0.582 643.0 23 0.27 125 - 60.0 0.581 657.0 24 0.25 - 232.5 74.2 0.583 687.0 25 0 - 199.7 57.7 0.581 690.0

According to Table 2, the resin of the fibrous layer forming the automobile interior material according to the present invention has a ring compound content of 1 wt% or less, specifically 0 to 0.86 wt%. It is also understood that the resin has a melting point of 180 ° C to 250 ° C or a softening point of 100 ° C to 150 ° C. The intrinsic viscosity (I.V) corresponds to from 0.5 dl / g to 0.75 dl / g, specifically from 0.55 dl / g to 0.6 dl / g. It is also understood that the glass transition temperature is in the range of 50 캜 to 80 캜, specifically in the range of 57 to 77 캜.

Example  1 to 25: Fibrous layer  Produce

The first fibers prepared in Production Examples 1 to 25 were mixed with a polyester resin second fiber having a melting point of 255 캜 or higher and thermoformed while pressing at 130 캜 to form a fiber layer.

The second fiber was obtained in the same manner as in Production Example 1, except that a product (product name: SD, Semi-dull chip) manufactured by Hubis Co., Ltd. was used.

The mixing ratio of the first fiber and the second fiber is shown in Table 3 based on the weight.

Example No. 2. First fiber content Second fiber content 1-5 3.5 6.5 6 to 10 4 6 11 ~ 15 5 5 16-20 6 4 21 ~ 25 7 3

Experimental Example  2.

The basis weight, flexural modulus (stiffness) and flexural strength of the fiber layer samples prepared in Example 1 were measured.

The flexural modulus and flexural strength were measured according to ASTM D 790 when the support spacing of the specimen was fixed at 100 mm and the flexural load was applied at a rate of 5 mm / min. The results are shown in Table 2 .

division Example 1 Basis weight (g / m ² ) 980 Flexural modulus (MPa) 450 Flexural Strength (MPa) 12

In the same manner as in Table 4 above, the basis weight of each of the samples of Examples 2 to 25 was measured, and it was confirmed that all the samples had a basis weight of 1,000 g / m ² or less.

The flexural modulus of the samples of Examples 2 to 25 was measured, and it was confirmed that they were within the range of ± 10% as compared with the case of Example 1. [

Example  26 to 28

The fibrous layers according to Examples 6 to 8 were laminated on both sides of the PET resin foam sheet. Specifically, a PET resin foam sheet was prepared by the following procedure.

First, 100 parts by weight of a polyethylene terephthalate (PET) resin was dried at 130 캜 to remove moisture. In the first extruder, 100 parts by weight of the PET resin from which the moisture was removed and 100 parts by weight of the PET resin from which the water had been removed were mixed with 100 parts by weight of pyromellitic acid 1 part by weight of hydride, 1 part by weight of talc and 0.1 part by weight of Irganox (IRG1010) were mixed and heated to 280 DEG C to prepare a resin melt. Then, carbon dioxide gas and pentane were mixed as a blowing agent in a ratio of 5: 5 to the first extruder, and 5 parts by weight of 100 parts by weight of the PET resin was added thereto, followed by extrusion foaming to prepare a polyester resin foam layer. The density of the polyester resin foam layer prepared was about 300 kg / m ³ , the thickness was about 2 mm, and the basis weight was about 600 g / m ² .

At this time, the total thickness of the manufactured laminate was 8 mm, and the mass per unit area was adjusted as shown in Table 5 below.

Example No. 2. Mass per unit area (g / m ² ) Example 26 1500 Example 27 1700 Example 28 2000

Experimental Example  3

The samples according to Examples 11 to 13 were subjected to experiments for measuring dimensional change. Specifically, the step of leaving each of the manufactured vehicle interior materials at a temperature of 90 ± 1 ° C for 24 hours; And a step of allowing to stand for 24 hours at a temperature of 50 ± 1 ° C and a relative humidity of 90%, and then the dimensional change ratio was measured by the following equation (1). The results are shown in Table 6 below.

[Equation 1]

| V ₁ -V ₀ | / V ₀ x 100

In the above equation (1)

V ₀ is the volume (mm ³ ) of the vehicle interior before exposure to the harsh conditions,

V ₁ is the volume (mm ³ ) of the vehicle interior after exposure to the harsh conditions.

Example No. 2. Dimensional change ratio (%) Example 11 0.5 Example 12 0.3 Example 13 0.2

Referring to Table 6, it can be confirmed that the automotive interior material according to the present invention exhibits a remarkably low dimensional change rate. Thus, it can be seen that the automotive interior material according to the present invention has excellent durability.

Experimental Example  3: Sound absorption and Sound insulation performance  Measure

For the samples according to Examples 16 to 18, the sound absorption rate and the differential tone were measured. The measurement method is described below, and the results are shown in Table 7 below.

(1) Sound absorption rate measurement

The absorption coefficient of 0 ~ 10,000 Hz was measured using the KS F 2805 reverberation method and NRC (noise reduction coefficient) was calculated. NRC is the average value of sound absorption rate at 250, 500, 1,000 and 2,000 Hz.

(2) Car tone  Measure

The permeation loss values of frequencies 1 to 8,000 Hz were determined using an Apamat measuring instrument based on KS F 2080. For comparison, the transmission loss values of 8,000 Hz were compared.

Example No. 2. Sound absorption rate (NRC) Differential tone (dB) Example 16 0.4 11 Example 17 0.4 14 Example 18 0.4 18

Referring to Table 7, it can be seen that the fibrous layer according to the present invention is excellent in both the sound absorption ratio and the differential tone.

Experimental Example  4: Evaluation of tensile strength and flammability

For the samples according to Examples 1 to 25, tensile strength and combustibility were evaluated. Tensile strength was evaluated according to ASTM D 638, and flammability was evaluated according to KS M ISO 9772.

As a result of the evaluation, it was confirmed that the samples of Examples 1 to 25 had a tensile strength of 70 MPa or more and a combustibility of 70 or less.

Claims (15)

And a fiber layer comprising a first fiber and a second fiber,
Wherein the first fiber comprises:
A core portion formed of a polyester resin having a melting point higher than 250 캜, and
And a sheath portion formed of a polyester resin having a melting point of 180 ° C to 250 ° C or a softening point of 100 ° C to 150 ° C,
Wherein the second fiber is a fiber formed of a polyester resin having a melting point higher than 250 占 폚.
The method according to claim 1,
Wherein the fibers forming the fibrous layer are partially fusion-bonded to each other.
The method according to claim 1,
Wherein the mixing ratio of the first fiber and the second fiber is in the range of 3.5: 6.5 to 7: 3 by weight.
The method according to claim 1,
A tensile strength of 10 to 150 MPa based on ASTM D 638,
Automotive interiors with combustibility less than 80 based on KS M ISO 9772.
The method according to claim 1,
Leaving it at a temperature of 90 ± 1 ° C for 24 hours; And a step of allowing to stand for 24 hours at a temperature of 50 ± 1 ° C and a relative humidity of 90%, the vehicle interior material satisfying the following formula (1)
[Equation 1]
| V ₁ -V ₀ | / V ₀ x 100? 5%
In the above equation (1)
V ₀ is the volume (mm ³ ) of the vehicle interior material before exposure to the harsh conditions,
V ₁ is the volume (mm ³ ) of the automotive interior material after exposure to the harsh conditions.
The method according to claim 1,
The sound absorption rate measured according to KS F 2805 is 0.4 NRC or more,
An automotive interior material having a permeation loss value of 10 dB or more as measured in accordance with KS F 2080.
The method according to claim 1,
Wherein the sheath portion of the first fiber is a polyester resin containing a repeating unit represented by the following Formula 1 and Formula 2:
[Chemical Formula 1]

(2)

In the above formulas (1) and (2)
m and n represent mole fractions of the repeating units contained in the polyester resin,
n is 0.05 to 0.5 based on m + n = 1.
8. The method of claim 7,
Wherein the sheath portion of the first fiber further comprises a repeating unit represented by the following Formula 3:
(3)

In Formula 3,
X is a 2-methylpropylene group, an ethylene group or an oxydiethylene group,
r is the mole fraction of the repeating units contained in the low melting point polyester resin, and is not more than 0.3.
The method according to claim 1,
The polyester resin forming the first fiber contains a cyclic compound having a degree of polymerization of 2 to 3 in an amount of 1% by weight or less based on the total weight.
The method according to claim 1,
The automotive interiors include:
A polyester resin foam layer; And
And a polyester resin fiber layer formed on one or both sides of the polyester resin foam layer.
11. The method of claim 10,
The polyester resin foam layer is a foamed sheet of a polyethylene terephthalate resin,
Wherein the fiber layer is a polyethylene terephthalate resin fiber.
The method according to claim 1,
Wherein the automobile interior material is a trunk interior material, a tray package, a floor under cover or a car mat.
Thermoforming a fiber layer comprising a first fiber and a second fiber in a temperature range of 80 to 200 < 0 > C,
The first fiber is a composite fiber comprising a core portion formed of a polyester resin having a melting point higher than 250 캜 and a sheath portion formed of a polyester resin having a melting point of 180 캜 to 250 캜 or a softening point of 100 캜 to 150 캜 ,
Wherein the second fiber is formed of a polyester resin having a melting point higher than 250 占 폚.
14. The method of claim 13,
Wherein the sheath portion of the first fiber is a polyester resin comprising a repeating unit represented by the following Formula 1 and Formula 2:
[Chemical Formula 1]

(2)

In the above formulas (1) and (2)
m and n represent mole fractions of the repeating units contained in the low melting point polyester resin,
n is 0.05 to 0.5 based on m + n = 1.
14. The method of claim 13,
Before or after the thermoforming step,
A polyester resin foam layer; And
Further comprising the step of laminating the fiber layers on one or both sides of the polyester resin foam layer.