JPH0939169A - Interior material for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof sheet having excellent flexibility, tear strength and cold resistance, and excellent heat fusing property (leister workability) and lightness. SOLUTION: This interior material for vehicle comprises at least a fiber layer and a layer consisting of propylene-α-olefin block copolymer having physical property. In a crystallization temperature curved line to be measured by using a differential scanning calorimeter, a main crystallization peak temperature is set to 85-95 deg.C, a half value width of the main crystallization peak temperature is set to 3-l0 deg.C, a secondary crystallization peak temperature is set to 65-75 deg.C, and a rate of a secondary crystallization peak area to a main crystallization peak area is set to 3-15%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interior material suitably used for interiors such as ceilings, floors and doors of vehicles such as automobiles.

[0002]

2. Description of the Related Art Interior materials for vehicles such as automobiles are required to have heat insulating properties and sound insulating properties in addition to flexibility and corrosion sensitivity. As these interior materials, a carpet in which a non-woven fabric is provided on the surface of a base material, and a laminate backed with felt or urethane foam on the back side of the base material are used. Conventionally, polyvinyl chloride resin (PVC) has been widely used as these substrates. But PVC is
Since it has a relatively large specific gravity, and usually contains a large amount of a plasticizer, it has a problem that the fiber layer such as carpet and felt is contaminated, or the adhesive strength with the fiber layer is inferior in stability over time. In addition, there is concern about the generation of toxic gas during waste treatment, which causes environmental problems. Therefore, in recent years, as an alternative to this, an interior material using a polyolefin resin has been proposed (for example, JP-A-1-61213,
JP-A-1-61214, JP-A-2-292035
Issue Bulletin).

[0003]

However, all of these interior materials have a problem that they are inferior in flexibility and cushioning property as compared with PVC. The present invention has been made in view of the above circumstances, and an object thereof is to provide an interior material for a vehicle, which is improved in flexibility and cushioning property, and is based on a polyolefin resin having excellent heat resistance as a base material. .

[0004]

As a result of intensive studies, the present inventors have found that the above object can be achieved by a specific propylene-α-olefin block copolymer, and based on such findings, The invention was completed.
That is, the present invention provides a vehicle interior material comprising at least two layers of (A) a fiber layer and (B) a layer composed of a propylene-α-olefin block copolymer having the following physical properties. In a crystallization temperature curve measured using a differential scanning calorimeter, (a) main crystallization peak temperature: 85 to 95 ° C. (b) half width of main crystallization peak temperature: 3 to 10 ° C. (c) secondary Crystallization peak temperature: 65 to 75 ° C. (d) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15%

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The (A) fiber layer in the present invention is not particularly limited, and known materials such as felt and carpet can be used. Felts are classified into woven felts, compressed felts and needlestick felts and are used for construction, automobiles, vehicles and papermaking.
Woven felt is spun by a woolen method, and in many cases, wool is usually blended with polyamide or polyester. Compressed felt uses crispness and is made using heat, moisture, and pressure. Further, the needlestick felt is mainly manufactured by a needle punch method.

As the constituent material of the felt, there are synthetic fibers made of synthetic resins such as polyester, polyamide, polyethylene, polypropylene, polyacrylonitrile, rayon and the like, natural fibers such as cotton, wool, jute, and coarse beef, and their mixed spinning. The felt used in the present invention may have its outer surface covered with a synthetic resin, a non-woven fabric or the like in order to prevent the fibers constituting the felt from falling off and improve the compression recovery property. As a method for covering the outer surface, there are a heat fusion method, a method of spraying an emulsion resin, a roll coating method and the like. Also, the carpet is usually polyester,
It has a structure in which a fiber made of synthetic fiber such as polyamide, polyacrylonitrile, polypropylene and the like and a backing material are provided on the back surface thereof. Specifically, a carpet is one in which fibers are woven into a base cloth, and the base cloth is most commonly woven cloth such as jute (burlap), polypropylene, or polyvinyl alcohol. The types of carpets are roughly classified into woven carpets, tufted carpets, knitted carpets and needle punched carpets.

A tufted carpet is manufactured by piercing a tufting raw yarn into a base fabric by a tufting machine to form a raw fabric, and applying latex, emulsion or the like to prevent the yarn from falling off. Tufted carpets also use tufting, which mainly uses filament yarns and loop pile carpets in which the yarns stabbed during tufting are cut at the carpet surface, and spun yarns as the yarns. Sometimes divided into cut pile carpets that are cut on the carpet surface. As the raw yarn used for the tufted carpet, wool, rayon, acrylic, polyamide, polyester, polypropylene, PVC, polyvinyl alcohol and the like are used, and two or more kinds of these may be mixed and used.

The knitted carpet is a warp-knitted carpet, and a backing similar to a tufted carpet is used. Needle punch carpet
Generally, a plain weave fabric of polypropylene is used as a base fabric, and a web of polypropylene, polyamide, acrylic fiber or the like is laminated on both sides of these fabrics in a sandwich shape. In the needle-punched carpet, the web is pierced by the needle through the base fabric, and the fibers are prevented from falling out due to the entanglement of the webs. Further, the back surface is subjected to impregnation processing (backing processing) using latex, emulsion or the like. As the (A) fiber layer of the present invention, the above felt or carpet can be appropriately used according to the purpose.

Further, (B) propylene-in the present invention
The α-olefin block copolymer (hereinafter referred to as “BPP”) is composed of a polypropylene block and a copolymer block of propylene and another α-olefin. Examples of the polypropylene block include homopolypropylene or a random copolymer of propylene and another α-olefin (the α-olefin copolymerization ratio is less than 5 mol%). On the other hand, examples of the copolymer block with α-olefin include a random copolymer of propylene and another α-olefin (the α-olefin copolymerization ratio is 5 mol% or more). Α-occupying in the copolymer block
The content of olefin is usually 30 to 70 mol%, and 3
2-68 mol% is preferable, and 35-65 mol% is particularly preferable.

The above-mentioned other α-olefins include those having 2 to 12 carbon atoms (excluding 3), and specific examples thereof include 1-butene, 3-methyl-1-butene,
3-methyl-1-pentene, 4-methyl-1-pentene, 4,4-dimethyl-1-pentene, vinylcyclopentane, vinylcyclohexane and the like can be mentioned. These α-olefins may be used alone or in combination of two or more. Further, the proportion of the copolymer block in BPP is preferably 30 to 70% by weight, and particularly preferably 40 to 68% by weight. Further, B of the present invention
PP is required to have the following physical properties.

In a crystallization temperature curve measured using a differential scanning calorimeter, (A) main crystallization peak temperature: 85 to 95 ° C. (B) main crystallization peak temperature half-value width: 3 to 10 ° C. ) Secondary crystallization peak temperature: 65 to 75 ° C (D) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15% The crystallization temperature curve measured using a differential scanning calorimeter is:
BPP is heated to 230 ° C and held for 5 minutes, then 20 ° C
It is obtained by cooling to −30 ° C. at a temperature decreasing rate of / min. An example of the crystallization temperature curve of BPP of the present invention is shown in FIG. Main crystallization peak temperature (hereinafter "Tcp1")
Is 85 to 95 ° C, preferably 88 to 94 ° C, and particularly preferably 89 to 93 ° C. Tcp1 is 85 ℃
If it is less than 1, the moldability is poor. On the other hand, if the temperature exceeds 95 ° C, the flexibility and the cold resistance are deteriorated, which is not preferable. The full width at half maximum of Tcp1 (hereinafter referred to as “δ”) is the peak width at a position corresponding to 50% of the height of Tcp1, and the value is 3 to.
10 ° C., preferably 3.5-8 ° C., especially 4-7 ° C.
Is preferred. When δ is less than 3 ° C, flexibility and impact resistance are poor. On the other hand, if it exceeds 10 ° C, the transparency and moldability are poor.

The secondary crystallization peak temperature (hereinafter referred to as "Tc
p2 ") is 65 to 75 ° C, preferably 67 to 73 ° C, and particularly preferably 68 to 72 ° C. Tcp2 is 6
If it is less than 5 ° C, the moldability is poor. On the other hand, if it exceeds 75 ° C or does not have Tcp2 at all, the elongation at low temperature is insufficient, which hinders use in cold regions. The ratio of the secondary crystallization peak area to the main crystallization peak area is 3 to 15%,
4 to 13% is preferable, and 5 to 11% is particularly preferable.
If the ratio of the peak area is less than 3%, the moldability, rigidity and cold resistance are poor. On the other hand, if it exceeds 15%, the flexibility is deteriorated, which is not preferable.

Further, in the BPP of the present invention, it is preferable that the eluted components measured by cross fractionation chromatography have the following proportions. (I) Elution amount below 0 ° C: 50 to 65% by weight (ii) Elution amount above 0 ° C and 90 ° C: 10 to 28% by weight (iii) Elution amount above 90 ° C and 130 ° C: 15 to 25% by weight The fractionation chromatograph is called a temperature-raising fractionator, and it uses a TREF (Temperature Rising Elu
GPC is measured online after fractionation by comonomer or stereoregularity by ionization fractionation chromatography, and a three-dimensional structure distribution of elution temperature-molecular weight-component amount can be obtained. About this device, TAKAO US
AMI et al; Jounal of Applied Polyner Science Applie
d Polymer Symposium Vol.52, pp145-158 (1993) or JP-A-7-40519.

Regarding the elution ratio by this cross fractionation chromatograph, (i) the elution amount at 0 ° C. or lower is preferably 50 to 65% by weight, and particularly preferably 55 to 60% by weight.
(Ii) The elution amount above 0 ° C and 90 ° C is preferably 10 to 28% by weight, and particularly preferably 15 to 25% by weight. (Iii)
The elution amount of more than 90 ° C and 130 ° C is preferably 15 to 25% by weight, and particularly preferably 17 to 22% by weight.

The polymerization of BPP of the present invention is carried out by a slurry method in the presence of a liquefied α-olefin solvent such as hexane, heptane, kerosene, or another inert hydrocarbon or propylene, or a vapor phase polymerization method without a solvent. The temperature is in the range of room temperature to 130 ° C. Preferably, it is performed in the range of 50 to 90 ° C. The polymerization pressure is in the range of ^{2 to} 50 kg / cm ² . As the reactor in the polymerization step, a reactor generally used in this technical field can be appropriately used. For example, a stirred tank reactor, a fluidized bed reactor, a continuous reactor using a circulation reactor,
It can be performed by either a semi-batch method or a batch method.

Specifically, it can be obtained by using a known multistage polymerization method. That is, it is a method in which homopolymerization of propylene or copolymerization of propylene with other α-olefin is carried out in the reactor of the first stage, and then copolymerization of propylene and α-olefin is carried out in the reaction of the second stage. , For example, JP-A-2-25
It is described in JP-A-8854, JP-A-3-97747, JP-A-3-205439, and the like.

The melt flow rate (MFR) of BPP used in the present invention is not particularly limited and may be appropriately selected depending on the molding method, but in the calender molding and extrusion molding which are usually used for molding a sheet. 0.1 to 20 g / 10 minutes is suitable. Further, in the BPP of the present invention, other additives conventionally used in thermoplastic resins (for example, antioxidants, weather resistance stabilizers, antistatic agents, lubricants, antiblocking agents, antifog agents, dyes, pigments, Oil, wax, filler, etc.) can be added in an appropriate amount within the range not impairing the object of the present invention.

Examples of such additives include 2,5-di-t-butylhydroquinone and 2,2 as an antioxidant.
6-di-t-butyl-p-cresol, 4,4′-thiobis- (6-t-butylphenol), 2,2-methylene-bis (4-methyl-6-t-butylphenol),
Octadecyl-3- (3 ', 5'-di-t-butyl-
1'-hydroxyphenyl) propionate, 4,4 '
-Thiobis- (6-butylphenol), as an ultraviolet absorber, ethyl-2-cyano-3,3-diphenylacrylate, 2- (2'-hydroxy-5-methylphenyl) benzotriazole, 2-hydroxy-4-oct Xybenzophenone, dimethyl phthalate as a plasticizer,
Diethyl phthalate, wax, liquid paraffin, phosphate ester, antistatic agent pentaerythritol monostearate, sorbitan monopalmitate, sulfated oleic acid, polyethylene oxide, carbon wax,
As a lubricant, ethylene bis stearamide, butyl stearate, etc., as a colorant, carbon black, phthalocyanine, quinacridone, indoline, azo pigment, titanium oxide, red iron oxide, etc., as a filler, glass fiber, asbestos, mica, wollastonite, silica Calcium acid, aluminum silicate, calcium carbonate and the like.
Also, many other polymer compounds may be blended to the extent that the effects of the present invention are not impaired.

The vehicle interior material of the present invention comprises the above (A).
The fiber layer and the (B) BPP can be obtained by a known molding method such as compression molding, extrusion laminate molding, sandwich laminate molding, and injection insert molding. The layer structure of the interior material of the present invention may be such that it has at least one (A) layer and one (B) layer, for example, (A) / (B), (A) / (B) /
Examples thereof include (A) and (B) / (A) / (B) / (A). Among these, (A) / (B) /
A laminated material composed of carpet / (B) / felt in which a felt and a carpet are used as the component (A) in the configuration of (A) is preferable.

In the interior material of the present invention, the thickness of the layer (A) is not particularly limited, and the thickness of the layer (B) is usually 0.1 to 1.
0 mm, preferably 0.2 to 8 mm, 0.3 to 5
mm is preferred. Further, when a high interlayer adhesive strength is required, a known adhesive may be used. As the adhesive, a hot melt adhesive, a modified polyolefin obtained by grafting an unsaturated carboxylic acid or an anhydride thereof onto a polyolefin, a copolymer of an α-olefin and an unsaturated carboxylic acid or an anhydride thereof, a synthetic rubber adhesive, Examples include polyurethane-based adhesives and epoxy-based adhesives.
Further, the interior material of the present invention may be a laminate of a foam layer made of polyethylene, polypropylene, polyurethane or the like.

[0021]

The present invention will be described in more detail with reference to the following examples. In addition, the measuring method and apparatus of each physical property are shown below. (1) Temperature 230 ° C, load 2.1 according to MFR JIS K7210
It was measured at 6 kg. (2) DSC method crystallization temperature and ratio of secondary peak area to main peak area (SMA) Equipment: PERKIN-ELMER DSC7 type Sample weight: Approximately 3 to 5 mg Measurement method: The temperature of the sample is increased to 230 ° C After holding for 5 minutes, the temperature was lowered to -30 ° C at a rate of 20 ° C / minute to obtain a crystallization temperature curve. From the obtained crystallization temperature curve, the main peak temperature, the secondary peak temperature and the ratio of the secondary peak area to the main peak area (SMA) were determined. (3) Cross fractionation chromatograph device: Yuka Denshi T-150A type sample solution: Orthodichlorobenzene with a polymer concentration of 0.4% by weight TREF column: 4.6 mmΦ × 150 mm Filler: Glass beads Column temperature distribution: Within ± 0.1 ° C GPC column: SHODEX UT806M, 807 Detection unit: Infrared detection method (MIRAN-1A) Solvent flow rate: 1.0 ml / min Injection amount: 0.5 ml Temperature rising rate: 1 ° C / min Measurement method: Polymer The solution was introduced into TREF, and the temperature was lowered to 0 ° C. at a temperature lowering rate of 140 ° C./min.
It is kept for a minute to be adsorbed on the filler, and then the temperature is raised to 140 ° C. at the above temperature rising rate to obtain an elution curve.

(4) Heat resistance After being exposed in a gear oven at a temperature of 80 ° C. for 24 hours, the shape change was visually observed and evaluated according to the following four grades. ◎ ・ ・ ・ ・ No twisted state or sagging at all ○ ○ ・ ・ ・ Although there is some twisted state, it can withstand use △ ・ ・ ・ ・ Twisted state has some drooping × ・ ・ ・ ・ Twisted state and (5) Heat cycle property After exposed to a gear oven at a temperature of 100 ° C for 8 hours, −
The sample was stored in a freezer at 30 ° C. for 3 hours and then left in a thermostatic chamber at a temperature of 23 ° C. for 3 hours, and the twisted state of the sample was evaluated by visual observation according to the following three grades. ○ ・ ・ ・ ・ Twisted state is not seen at all △ ・ ・ ・ ・ Twisted state can be used even though it is slightly usable × ・ ・ ・ ・ Twisted state is extremely unusable (6) Cushioning When held by hand The following four grades were used to evaluate the touch. ◎ ・ ・ ・ ・ ・ ・ Cushioning property is very good ○ ・ ・ ・ ・ Cushioning property is slightly inferior △ ・ ・ ・ ・ Cushioning property is slightly hard and inferior × ・ ・ ・ ・ Very hard feeling and cushioning property is inferior

Further, (A) a fiber layer having a thickness of 5 mm in which polyester fibers are melt-coated on the back surface and polypropylene is melt-coated.
(Hereinafter referred to as "felt 1") and a 1 mm-thick felt (hereinafter referred to as "felt 2") obtained by melt-coating polyester fiber and polypropylene on the back surface. Further, as BPP, BPP1 to BP shown in Table 1 produced according to the multistage polymerization method described in the above-mentioned prior art document.
P5 was used. BPP5 is for comparison. Also,
Table 1 shows the DSC measurement results of BPP1 to 5 and the measurement results of cross fractionation.

[0024]

[Table 1]

Examples 1 to 4 and Comparative Example 1 100 parts by weight of each BPP shown in Table 2 was used as a stabilizer.
0.05 parts by weight of t-butyl-p-cresol, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] 0.1
Parts by weight, 0.1 parts by weight of calcium stearate and 0.4 parts by weight of an ultraviolet stabilizer (HSLS944) are mixed and mixed using a super mixer (SMV20 type) manufactured by Kawata Seisakusho, and then a twin-screw extruder (Kobe Seisakusho). Made by KTX3
7) was used to make pellets.

The obtained pellets were attached to a T-die with a diameter of 65 mm.
φ vent type composite sheet forming machine (NVC, NVC)
Die temperature 230 ℃, chill roll temperature 40 ℃,
A 2.0 mm-thick sheet was extruded at a take-off speed of 0.3 m / min. At the same time, the felt 1 was fed to the upper side of the sheet and the felt 2 was fed to the lower side thereof, and the sheets were pressure-bonded with a cooling roll and a nip roll to be laminated. . The resulting laminated sheet was evaluated for heat resistance, heat cycle property and cushioning property. Table 2 shows the obtained results.

[0027]

[Table 2]

[0028]

INDUSTRIAL APPLICABILITY The vehicle interior material of the present invention is useful because it has improved flexibility and cushioning properties, and has excellent heat resistance and light weight.

[Brief description of drawings]

FIG. 1 is a DSC of the propylene block copolymer of the present invention.
It is an example of a crystallization temperature curve.

Claims (3)

[Claims] 1. A vehicle interior material comprising at least two layers, (A) a fiber layer and (B) a layer made of a propylene-α-olefin block copolymer having the following physical properties.
In a crystallization temperature curve measured using a differential scanning calorimeter, (a) main crystallization peak temperature: 85 to 95 ° C. (b) half width of main crystallization peak temperature: 3 to 10 ° C. (c) secondary Crystallization peak temperature: 65 to 75 ° C. (d) Ratio of secondary crystallization peak area to main crystallization peak area: 3 to 15% 2. A propylene-α-olefin block copolymer comprising a polypropylene block in an amount of 30 to 70% by weight.
And a copolymer block of propylene and another α-olefin in an amount of 70 to 30% by weight. 3. The vehicle interior material according to claim 1 or 2, wherein the elution components measured by cross fractionation chromatography of the propylene-α-olefin block copolymer have the following proportions. (I) Elution amount below 0 ° C: 50 to 65% by weight (ii) Elution amount above 0 ° C and 90 ° C: 10 to 28% by weight (iii) Elution amount above 90 ° C and 130 ° C: 15 to 25% by weight