KR20110020039A - TFT sheet composition, TFT sheet and automobile interior including the same - Google Patents

Abstract

The present invention relates to a TPO (Thermoplastic Olefin, thermoplastic olefin) sheet composition, a TPO sheet and an automotive interior material comprising the same, in more detail, a partially crosslinked TPO resin, an uncrosslinked TPO resin, a polypropylene resin, an ethylene octene rubber, A TPO sheet composition comprising a linear low density polyethylene resin and the like and a TPO sheet produced by calendering the same. In addition, the present invention relates to an automobile interior material having a high embossed transfer rate manufactured by coating the surface of the TPO sheet with an aqueous coating agent and then vacuum forming the female.

The TPO sheet of the present invention is excellent in formability due to its excellent interlocking properties with an aqueous coating agent such as an aqueous primer and a surface treatment agent, and has a very high emboss transfer rate even when processed by female vacuum forming. In addition, the automotive interior material of the present invention has excellent physical properties such as solvent resistance, abrasion resistance, scratch resistance, light resistance and chemical resistance, but has a high embossed transfer rate, making it suitable for use as a skin material of high-end automotive interior parts.

Thermoplastic Olefin, Linear Low Density Polyethylene, FEMALE Vacuum Forming

Description

TPO sheet compositions, TPO sheet compositions, TPO sheet and Interior trim of vehicle containing that}

The present invention relates to a TPO sheet composition comprising a partially crosslinked TPO resin, an uncrosslinked TPO resin, a polypropylene resin, an ethylene octene rubber, a linear low density polyethylene, and the like, and a TPO sheet produced by calendering the same. In addition, the present invention relates to an automobile interior material having a high embossed transfer rate manufactured by coating the surface of the TPO sheet with an aqueous coating agent and then vacuum forming the female.

Conventionally, automotive interior parts, such as instrument panels, door trim panels, headlinings, and the like, are made of PVC, PVC / ABS ALLOY extrusion sheets, or calendering. ) Sheet has been widely used, but in recent years, it has been rapidly replaced by thermoplastic polyolefin-based elastomer (hereinafter referred to as 'TPO') sheet which is advantageous in terms of environmental friendliness, light weight, fogging and odor.

Automobile interior skin materials have improved physical properties such as scratch resistance and abrasion resistance, improved chemical properties such as chemical resistance and solvent resistance, improved durability such as light resistance and heat resistance, low gloss (prevention of driver's vision due to surface reflection) and other surroundings. In many cases, surface treatment agents are used for color integration with parts. Since existing TPO sheets have nonpolar and high crystallinity in their molecular structure, they are extremely poor in adhesion and thus can be used for surface treatment such as flame treatment, ozone treatment, and plasma treatment. After subjecting the chlorinated polyolefin resin primer treatment, the acrylic resin base coating agent and the urethane resin clear coating agent have been sequentially coated and used. However, this coating method was excluded and recently developed an aqueous coating agent and a primer that can be applied to the interior materials of automobiles for the purpose of reducing VOC and odor.However, in order to apply to the TPO sheet which has increased rapidly, There is a problem to solve the surface properties and elongation decrease.

In addition, efforts are being made to improve the emboss transfer rate of the interior skin material. Although the male type vacuum molding has a low price advantage, the emboss loss of the edge part and the deep drawing part is low due to high temperature molding. There is a problem. In order to overcome this problem, a female vacuum molding method is used in which an emboss is formed in a mold and then transferred to the emboss. However, adhesion between a surface coating agent such as a surface treatment agent and a sheet such as a TPO sheet is not good. There is a problem of low emboss transfer rate.

The present inventors endeavored to produce automotive interior materials having high embossing transfer rates and excellent physical properties. As a result, the present inventors have excellent interconnectability with aqueous coating agents such as aqueous primers and surface treatment agents, and manufacture automotive interior materials having excellent physical properties by female vacuum forming. Knowing the composition of the TPO sheet and the blending ratio thereof, the present invention was completed. That is, an object of the present invention is to provide a TPO sheet composition, a TPO sheet and an automotive interior material comprising the same.

The present invention for solving the above problems 35 to 45% by weight of partially crosslinked TPO resin, 5 to 15% by weight of non-crosslinked TPO resin, 10 to 20% by weight polypropylene resin, 10 to 20% by weight ethylene octene rubber, low density polyethylene on line It is an object to provide a TPO sheet composition comprising 10 to 20% by weight of resin and 5 to 10% by weight of inorganic filler.

In addition, an object of the present invention is to provide a TPO sheet produced by calendering the TPO sheet composition.

Another object of the present invention is to provide an automotive interior material including the TPO sheet.

Since the TPO sheet made of the TPO sheet composition of the present invention has excellent crosslinking properties with an aqueous coating agent such as an aqueous primer and a surface treatment agent, a high-quality automobile having a very high emboss transfer rate even when female vacuum molding is performed. Production of interior materials is possible. In addition, the automotive interior material of the present invention is excellent in physical properties such as solvent resistance, abrasion resistance, scratch resistance, light resistance and chemical resistance, high emboss transfer rate, and does not cause an indoor smell of the car, so as a skin material of automotive interior parts It can improve the car interior sensitivity.

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

The TPO (Thermoplastic olefin) sheet composition of the present invention is characterized by containing a partially crosslinked TPO resin, an uncrosslinked TPO resin, a polypropylene resin, an ethylene octene rubber, a linear low density polyethylene resin, and an inorganic filler.

In the present invention, the partially crosslinked TPO resin, which is a composition of the present invention, is introduced as a raw material which is used to secure proper deflection property when increasing the melt strength, which is the property most necessary for the calendering method, and vacuum forming. In general, the olefin material has a problem that roll adhesion occurs during the calendering process due to a sharp drop in strength in the molten state.In order to improve this phenomenon, when an appropriate amount of crosslinked TPO is added, the strength is maintained even in the molten state, thereby calendering. This will be easy. In addition, the partially crosslinked TPO has a structure in which a PP (polypropylene) chain passes between the partially crosslinked rubbers, and thus uniformly elongates at the time of extension, thereby reducing the variation in product thickness after calendering. The partial crosslinked TPO resin is preferably used 35 to 45% by weight relative to the total weight of the TPO sheet composition of the present invention, wherein the amount of the partial crosslinked TPO resin is more than 45% by weight, contained in the partial crosslinked TPO The surface of the TPO sheet may be uneven due to rubber, which may cause bursting during molding, and when the amount is less than 35% by weight, the melt strength is lowered, causing adhesion during calendering molding or excessive deflection during vacuum molding. Since wrinkles may occur, it is preferable to use within the above range. In addition, the partial crosslinked TPO resin is preferably used hardness of Shore A 65, melt index (MI) 0.6 ~ 1.2 (230 ℃ / 5 Kg), specific gravity 0.87 ~ 0.89, partially crosslinked TPO resin having such physical properties Using it can minimize the change of properties when mixed with other raw materials.

The non-crosslinked TPO resin, which is one of the compositional materials of the present invention, has a lower melt strength than the crosslinked TPO, but has higher properties than the general olefin resin, and does not change the smell and physical properties because it does not use a crosslinking agent. The amount of the non-crosslinked TPO resin is preferably 5 to 15% by weight based on the total weight of the TPO sheet composition. At this time, when the amount of the non-crosslinked TPO resin is more than 15% by weight, the thickness change may be severe during calendering processing, causing problems of bursting and whitening, and when the amount is less than 5% by weight, it may be disadvantageous in smell and light resistance. It is good to use within. The non-crosslinked TPO resin preferably has a hardness of Shore A 90, a melt index (MI) of 0.6 to 0.8 (230 ° C., 2.16 Kg), a specific gravity of 0.89 to 0.91, and an extension of 600 to 700%. Good to do.

The polypropylene resin, which is one of the compositions of the present invention, is used to increase the shape retention force of the TPO sheet after calendering, and serves to reduce emboss change during female vacuum forming. . The amount of the polypropylene used is preferably 10 to 20% by weight based on the total weight of the TPO sheet composition, when the amount of the polypropylene exceeds 20% by weight, the melt strength may drop sharply and the calendering process may not be possible. If the TPO sheet is hardened, the phenomenon of bursting and the texture of the product may deteriorate during the vacuum vacuum molding. If the use is less than 10% by weight, the emboss holding force during the vacuum vacuum molding falls below 70%. Since a problem of deterioration in appearance quality may occur, it is preferable to use the above within the above range. The polypropylene resin is not particularly limited in the present invention, but the use of a homo type polypropylene has a small smell of the TPO sheet and little change due to temperature or light. In addition, the polypropylene resin is preferably used melt melt index (MI) 1.5 ~ 2.5 (230 ℃, 2.16 Kg), specific gravity 0.89 ~ 0.91, hardness Shore A 90 ~ 97, and 20 ~ 30% elongation. It is possible to obtain the effect of lowering the elongation rate which is increased in the partially crosslinked TPO resin and the noncrosslinked TPO resin.

Ethylene Octene Rubber (hereinafter referred to as 'EOR'), which is a compositional material of the present invention, is a resin used to improve the disadvantages of partially crosslinked TPO resins. When used together, EOR can be impregnated into the filler to impart a melt strength similar to that of partially crosslinked TPO, with a pronounced odor-improving effect. The grade of the EOR is divided according to the octene content (Grade) In the present invention, EOR resin is used that contains 40 to 50% by weight, more preferably 40 to 45% by weight of octene in the total weight of EOR It is good in terms of processability, and when the octene content exceeds 50% by weight, the hardness is lowered, so that the soft texture of the product is improved, but the calendering processability is poor, so it is preferable to use an EOR containing octene within the above range. In the present invention, the EOR is preferably used in the melt index (MI) 0.4 ~ 0.7 (190 ℃, 2.14 Kg), specific gravity 0.84 ~ 0.86, and hardness Shore A 65. The amount of the EOR is preferably used 10 to 20% by weight based on the total weight of the TPO sheet composition of the present invention, in which case the melt strength is lowered when the amount is more than 20% by weight, the TPO sheet vacuum forming When doing so, it may cause wrinkles due to excessive deflection, and an odor may occur when used at less than 10% by weight, so it is preferable to use within the above range.

The linear low density polyethylene (Linear Low Density PolyEthylene, hereinafter referred to as 'LLDPE') resin of another composition of the present invention because the molecular weight distribution is narrower than the low density polyethylene (LDPE) resin because there is no long side chain and only a short side chain In terms of molecular structure, the crystallinity is higher than that of the low-density polyethylene resin, and the melting point is high, so that the melting temperature range is advantageous. Further, not only the rigidity and the stress crack resistance are good, but also the tear resistance is large and the surface hardness is relatively large, so that a molded article having good gloss can be obtained. In addition, the linear low density polyethylene resin is excellent in rigidity, low temperature impact strength, stress crack resistance and heat resistance. The LLDPE resin may be used in an amount of 10 to 20% by weight based on the total weight of the TPO sheet composition of the present invention. In this case, when the amount of the LLDPE resin is less than 10% by weight, the flowability is lowered, resulting in poor calendering processability. When used in excess of 20% by weight, the product becomes hard and may burst due to uneven elongation during molding.

The inorganic filler, which is the composition of the present invention, is used to increase the mechanical properties of the TPO sheet, and may be used by mixing one or more selected from calcium carbonate, calcium oxide, mica and talc. The amount of the inorganic filler is preferably used 5 to 10% by weight, based on the total weight of the TPO sheet composition of the present invention, when used in excess of 5% by weight is less effective to combine EOR to improve the physical properties, TPO sheet composition may adhere to the roll during calendering, and when used in excess of 10% by weight, bursting may occur during molding due to hardness increase and elongation decrease in the molding process. It is desirable to. Although not particularly limited, it is preferable to use a quaternary inorganic filler having a specific gravity of 2.6 and a low odor.

In addition, the present invention relates to a TPO sheet, and relates to a TPO sheet produced by calendering the TPO sheet composition of all forms described above. Since the TPO sheet of the present invention has excellent adhesion to an aqueous coating agent such as an aqueous primer and a surface treatment agent, and thus has good adhesion, unlike the conventional TPO sheet, the TPO sheet has a problem of deterioration in surface properties and elongation caused by female vacuum forming. It can be overcome.

In addition, the present invention relates to a vehicle interior material comprising the TPO sheet, characterized in that the surface of the TPO sheet is coated with an aqueous coating agent, and then manufactured by female vacuum forming (female). Car interior material of the present invention including the TPO sheet is excellent in physical properties such as solvent resistance, wear resistance, scratch resistance, light resistance and chemical resistance, but the embossed transfer rate is higher than 80%, and does not cause an indoor odor of the car In addition, it can be used as a skin material of car interior parts to improve car interior sensitivity.

Hereinafter, the present invention will be described in more detail based on examples. However, the scope of the present invention is not limited by the following examples.

To prepare a TPO sheet composition having the composition and composition ratio shown in Table 1 below, and calendering it to prepare a TPO sheet.

division Example (% by weight) Comparative Example (% by weight) One 2 One 2 3 Partially crosslinked TPO resin ⁽¹⁾ 38 42 32 47 48 Uncrosslinked TPO Resin ⁽²⁾ 10 8 10 10 - Polypropylene Resin ⁽³⁾ 15 13 20 10 14 Ethylene Octene Rubber ⁽⁴⁾ 15 17 18 18 16 LLDPE Resin ⁽⁵⁾ 15 15 15 12 15 Inorganic fillers ⁽⁶⁾ 7 5 5 3 7 (1) Partially crosslinked thermoplastic olefin resin: hardness Shore A 65, melt index (MI) 0.9 (230 ° C./5 Kg), specific gravity 0.88
(2) Uncrosslinked thermoplastic olefin resin: hardness Shore A 90, melt index (MI) 0.7 (230 ° C./2.16 Kg), specific gravity 0.90, elongation 640%
(3) Polypropylene resin: hardness Shore A 94, melt index (MI) 2 (230 ° C./2.16 Kg), specific gravity 0.90, elongation 25%
(4) Ethylene octene rubber: hardness Shore A 65, melt index (MI) 0.6 (190 ° C / 2.16 Kg), specific gravity 0.85, octene content 42 wt%
(5) Low density polyethylene resin on line: LLDPE 3120, Hanwha Petrochemical
(6) inorganic fillers: calcium carbonate

Preparation Examples 1-2 and Comparative Preparation Examples 1-2

After coating the upper and lower ends of each of the TPO sheets prepared in Examples and Comparative Examples with an aqueous surface treatment agent, and then vacuum forming the same, to prepare automobile interior materials, respectively, Preparation Examples 1-2 and Comparative Preparation Examples 1- 2 was carried out.

Experimental Example

The physical properties of the automobile interior materials prepared in Preparation Example and Comparative Preparation Example were measured by the following method, and the results are shown in Table 2 below.

1) Tensile strength and elongation: The maximum load and elongation of a certain area were measured by using a tensile tester in accordance with ASTM D 638 with a test speed of 200 mm / min, a distance of 70 mm between the marks, and the test piece No. 1.

2) Tear Strength: Dumbbell B type specimens are clamped in the tensile tester according to KS M6518 and teared at a tensile rate of 200 mm / min.

3) Heat aging resistance: After maintaining for 300 hours in a forced convection oven maintained at 110 ± 2 ℃ temperature, the difference in ΔE _cmc and visual fade at 45 ° angle by spectrophotometer (ISO) The grade is determined by gray scale specified in A02.

4) Light aging resistance: Tester specified in accordance with ISO 105. After irradiating black panel temperature of 89 ± 3 ℃ and humidity of humidity 50 ± 5% RH at 126 MJ / ㎡, the difference of fading by naked eye is measured by ISO. The grade is determined by the gray scale specified in 105-A02.

5) Moisture resistance: After holding for 168 hours in saturated steam at 50 ± 2 ℃ and 98 ± 2% RH, take it out and leave for 1 hour at room temperature to observe the appearance change.

6) Chemical resistance: After reciprocating the epidermis surface 10 times with a gauze moistened with enough test solution indicated in the table below, let it stand for 1 hour at room temperature, and the difference in color fading due to the naked eye is gray scale specified in ISO 105-A02. Determine the grade by (GRAY SCALE).

Test solution Remarks GLASS CLEANER Alkaline GLASS CLEANER CLEANER Mixture of 95% distilled water and 5% neutral detergent WIND SHILD WASHER liquid With 50% isopropyl alcohol
50% distilled water mixture Gasoline white gas Glossy WAX HMC genuine or equivalent

7) Sun Cream Resistance: After laminating two sheets of white cotton cloth of equal size on aluminum plate (liquid 50 mm × 50 mm) according to GMN 10033, 0.25 g of oppertone waterbabies ^® SPF 45 sunscreen is applied to the entire surface. It is placed on the test piece and adhered to the aluminum plate with a load of 500 g. After leaving for 1 hour in a 80 ± 2 ℃ thermostat, take out, remove the white cloth and acrylic plate, leave at room temperature for about 10 to 15 minutes, wash with a neutral detergent and dry to determine the difference in color fading by the naked eye.

8) Odor: After heating the glass container of 4L at 100 ℃ for 1 hour, it is left at room temperature again for 1 hour to volatilize the odor in the glass container and cutting the specimen to 50mm × 60mm and then heating at 100 ℃ for 2 hours. After cooling, the mixture was left to stand at room temperature (23 ± 2 ° C) for 60 minutes, cooled, and the lid was opened for 3 to 4 cm to evaluate the smell by the evaluator.

9) Formability and Appearance of Mass Production Line: Applied vacuum molded TPO sheet to crash pad mass production line, and the moldability and work problem as finished product, and appearance of final finished product in the presence of quality manager of the company Evaluate.

Major Comments unit Example Comparative Example One 2 One 2 3 The tensile strength Kgf / ㎠ 123 112 127 105 110 Phosphorus strength Kgf / mmm 6.8 6.1 7.1 5.9 6.0 Elongation % 532 567 545 532 552 Heat aging resistance class 4 4 3-4 3-4 3-4 Light Aging Resistance class 3 3 3 2-3 3 Moisture resistance - Good Good Surface whitening Surface whitening Good Chemical resistance
class 4-5 4-5 3 3-4 3-4 Sun Cream Resistance - Good Good Good Good Good smell class 3 3 3 3 2 Mass Production Line Formability - Good Good Wrinkles Burst Wrinkles Product appearance
- Good Good Surface stain generation Luster Surface stain

Looking at the measurement results of the physical properties of Table 2, in the case of Comparative Examples 1 to 3, it can be confirmed that the overall physical properties are inferior. Through this, it can be confirmed that the automotive interior material produced by female vacuum molding the TPO sheet of the present invention has excellent physical properties.

Claims (10)

35 to 45 wt% of partially crosslinked thermoplastic olefin resin, 5 to 15 wt% of uncrosslinked thermoplastic olefin resin, 10 to 20 wt% of polypropylene resin, 10 to 20 wt% of ethylene octene rubber, 10 to 20 wt% of low density polyethylene resin TPO sheet composition comprising 5 to 10% by weight of inorganic filler. The TPO sheet composition of claim 1, wherein the partially crosslinked thermoplastic olefin resin has a hardness of Shore A 65, a melt index of 0.6 to 1.2 (230 ° C./5 Kg), and a specific gravity of 0.87 to 0.89. The TPO sheet composition of claim 1, wherein the non-crosslinked thermoplastic olefin resin has a hardness of Shore A 90, a melt index of 0.6 to 0.8 (230 ° C., 2.16 Kg), and a specific gravity of 0.89 to 0.91. The method of claim 1, wherein the polypropylene resin is homo (homo) type, hardness is Shore A 90 ~ 97, melt index 1.5 ~ 2.5 (230 ℃, 2.16 Kg), characterized in that the specific gravity is 0.89 ~ 0.91 TPO sheet composition. The TPO sheet composition of claim 1, wherein the ethylene octene rubber contains 40 to 50 wt% of octene in the total weight of the ethylene octene rubber. 6. The TPO sheet composition according to claim 5, wherein the ethylene octene rubber has a hardness of Shore A 65, a melt index of 0.4 to 0.7 (190 DEG C, 2.14 Kg), and a specific gravity of 0.84 to 0.86. The TPO sheet manufactured by calendering the said TPO sheet composition of Claims 1-6. An automotive interior material comprising the TPO sheet according to claim 7. The vehicle interior of claim 7, wherein the surface of the TPO sheet is coated with an aqueous coating agent, and then manufactured by female vacuum forming. 10. The vehicle interior material according to claim 9, wherein the embossed transfer rate is 80% or more.