KR100792894B1 - Method for manufacturing of skin materials for inner trim of automobile - Google Patents

Abstract

A method for manufacturing skin materials for automobile interior is provided to improve the antifouling property and the light resistance of a nanofiber web, which is used for the skin materials, by preparing the nanofiber web using a hybrid electrospinning system and performing plasma surface treatment on the nanofiber web. A spinning solution is prepared by mixing dimethylformamide as a solvent, polycarbonate and methylene diisocyanate as a main component, and 1,4-butanediol as a chain expander, and solution-polymerizing the resultant mixture. The spinning solution has 10-20 wt% of polyurethane powder based on 80 wt% of a solvent, and a viscosity of 20,000±2,000 cps. The spinning solution is electro-spun using a hybrid electrospinning spinneret(24) to obtain a polyurethane nanofiber web. An antifouling property and a light resistance of the polyurethane nanofiber web are improved by plasma surface treatment. The polyurethane nanofiber web is attached to a support through a laminating process.

Description

Method for Manufacturing Light-Resistant Nanofiber Skin Material for Automobile Interior Material {Method for Manufacturing of Skin Materials for Inner Trim of Automobile}

1 is a schematic diagram showing the configuration of a hybrid electrospinning system that can be used in the spinning process in the present invention,

2 is a view showing the viscosity and electrical conductivity change according to the spinning solution composition,

3 is a photograph of a nanofiber web taken using a scanning electron microscope,

4 is a graph showing a color difference comparison before and after plasma surface treatment;

Figure 5 is a photograph showing the finished nanofibrous skin material according to the present invention.

<Explanation of symbols for the main parts of the drawings>

20: degassing apparatus 21: solution reservoir

22: solution filtration device 23: solution transfer device

24: hybrid electrospinning detention 25: compressed air generator

26: blower 27: belt conveyor

29: roll calendar 30: winding device

31: solvent vapor recovery system

The present invention relates to a method of manufacturing a skin material for automotive interior materials, and more particularly, by manufacturing a nanofiber web using a hybrid electrospinning system and then performing a plasma surface treatment process as a post-processing, wear resistance and light resistance (weather resistance), surface The present invention relates to a nanofiber web having excellent properties and a method of manufacturing a light-resistant nanofiber skin material for automobile interior material, which enables to manufacture a skin interior material for automobile interior material using the same.

In general, the interior skin material for automobiles include a skin material for a headliner and a sun visor, a skin material for a door casing, a skin material for a sheet, and the like.

As the skin material for automobile interior materials, a nonwoven material made of a sheet-like polyvinyl chloride (PVC), a thermoplastic polyurethane (TPU), a thermoplastic polyolefin-based elastomer (TPO), or polyester is widely used.

As a technique for manufacturing such a conventional nonwoven skin material, a single fiber is prepared by cutting an island-in-the-sea composite fiber in which two polymer components (sea component and island component) are composited in an island-in-the-sea form, and then the carding process A method of manufacturing a nanofiber hybrid composite material by manufacturing a web with fibers and then needle punching to produce a nonwoven fabric, and then impregnating a polyurethane solution and eluting sea component in the island-in-the-sea composite fiber (short fiber). This is widely adopted.

Such nanofiber hybrid composite materials are used in various fields such as artificial leather, artificial suede, general clothing, sanitary napkins, diapers, packaging materials, miscellaneous materials, various filter materials, medical materials such as gene carriers, and defense materials such as bulletproof vests. .

However, since nanofibers are very weak in abrasion resistance, especially polyurethane-based nanofibers are poor in light resistance, it is difficult to use them as a skin material for automobile interiors, and thus there is little research on applying polyurethane nanofibers to skin materials. .

For polyurethane nanofibers, some researches have been made on applications such as membranes for wound dressing [J Biomed Mater Res B App Biomater. 2003 Nov 15; 67 (2): 675-9], patents relating to nanofiber manufacturing technology including polyurethanes are also a few of the following.

Korean Patent Laid-Open Publication No. 2005-78677 introduces a method for producing a continuous phase filament composed of nanofibers, and in particular, a polymer spinning solution is electrospun into a collector through a nozzle to produce a ribbon-shaped nanofiber web, and then By passing the nanofiber web through the air twisting device, twisting is applied to prepare nanofiber filaments in the form of continuous filaments, and subsequently, a method of stretching the nanofiber filaments is introduced.

Korean Patent Laid-Open Publication No. 2004-62743 introduces a method of manufacturing a nanofiber nonwoven fabric having a pattern, and when manufacturing a nanofiber nonwoven fabric by an electrospinning method, a groove is formed along a boundary of a pattern to be formed on a conductive plate or a mesh by a collector. The method which uses the laminated | stacked polymer film layer in one piece or the separate type is introduced.

Korean Patent Publication No. 2005-1578 discloses a method for producing a nanofiber hybrid composite material in which a nano nonwoven web is produced by an electrospinning method, and then the polymer solution for matrix is evenly filled in pores of a continuously or discontinuously produced nano nonwoven web. It introduces.

Patent Publication No. 2005-62683 introduces a method for producing nanofibers having excellent fiber forming ability, and in particular, the spinning solution, which is a polymer resin solution, is electrospun on a collector through a nozzle under high voltage, and the nanofiber having a nanometer fiber diameter is present. The manufacturing method which uses the collector provided with the heating apparatus as a collector when manufacturing fiber is introduced.

Patent Publication No. 2005-15610 introduces a method of coating nanofibers more uniformly on a nonwoven fabric by preventing drop when coating nanofibers on a nonwoven fabric by an electrospinning method for the purpose of manufacturing a filter.

Hereinafter, the problems of the prior art will be described.

The conventional nonwoven skin material manufacturing method requires a short fiber manufacturing process, a nonwoven fabric manufacturing process, and a sea component dissolution process, so that the process is complicated.There is a limit to improving the feel and appearance of the final product beyond a certain level. There is.

In addition, the sheet-like skin material produced according to the conventional manufacturing method retains the characteristics of the film without any air permeability, there is a problem in the touch.

In addition, the sheet-like skin material prepared according to the conventional manufacturing method retains the characteristics of the film without any air permeability as it is, and has a smooth touch, generally should be improved by the surface processing through embossing and the like.

In addition, in the manufacturing method of Patent Publication No. 2005-1578, the existing wet treatment method is used as it is, and there is still a problem in securing the required performance as a skin material.

In addition, the coating method of Korean Patent Laid-Open Publication No. 2005-15610 is a technique of complexing with an existing nonwoven skin material, which also has a problem in securing required performance as a skin material.

In addition, there is no research on improving light resistance by conventional plasma surface treatment.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a method for producing a highly durable nanofiber skin material for automobile interior using a hybrid electrospinning technology.

It is another object of the present invention to provide a flame retardant spinning solution manufacturing technology for manufacturing nanofibers, and to provide a method for manufacturing a skin interior material for automobile interior which can improve light resistance, weather resistance, surface properties, and the like.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

In order to achieve the above object, the present invention, in the method for producing a highly durable nanofiber skin material for automobile interior using a hybrid electrospinning technology,

Using dimethylformamide as a solvent, polycarbonate diol and methylenediisocyanate are used as the main raw materials, and 1,4-butanediol is used as a chain extender to prepare a spinning solution by mixing and polymerizing them, and finally, the polyurethane solid content is Preparing a spinning solution having a viscosity of 10 to 20 parts by weight and a viscosity of 20,000 cps ± 2,000, based on 80 parts by weight of a solvent;

Obtaining a non-woven polyurethane nanofiber web by electrospinning the spinning solution using a hybrid electrospinning cap;

Improving antifouling and light resistance by plasma surface treatment;

Adhering the obtained nanofiber web to a support through a laminating process;

It provides a method for producing a light-resistant nanofiber skin material for automobile interior, characterized in that it comprises a.

Here, 1,4-butanediol used as the chain extender is characterized by using 1 to 2 parts by weight based on the polyurethane solids.

In the preparation of the spinning solution, 0.1 to 0.5 parts by weight of anhydrous calcium chloride is further dissolved in the dimethylformamide.

In addition, in preparing the spinning solution, 1 to 10 parts by weight of a citric acid ester plasticizer is added to the polyurethane solids.

In addition, the citric acid ester plasticizers include triethyl citrate, acetyl triethyl citrate, acetyl tributyl citrate, and tri-ene-propyl citrate. -n-propyl citrate), characterized in that using one selected.

In addition, the plasma surface treatment is performed by injecting the polyurethane nanofiber web obtained by the electrospinning into a fluorine-based gas C ₂ F ₆ in the range of 80 sccm ± 16 sccm in a plasma surface treatment equipment.

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

The present invention relates to a method for manufacturing a highly durable nanofiber skin material for automobile interior using a hybrid electrospinning technology, in particular the present invention provides a flame retardant spinning solution manufacturing technology for nanofiber production, and also nanofiber web The present invention is to provide a skin material for automobile interior materials, and to improve surface properties by manufacturing a nanofiber web using a hybrid electrospinning system and then performing a plasma surface treatment process as a post-process.

In addition, the present invention is to provide a skin material for automotive interior material with improved wear resistance and light resistance (weather resistance), the nanofiber coating material according to the present invention is a new sense of five sense fiber material, high surface area, excellent breathability (breathability), existing It has unique surface structure and characteristics different from the material.

In addition, since there is no research and development on the durability and flame resistance of weather resistance, abrasion resistance, etc. required for automotive interior materials for nanofibers all over the world, the present invention provides low thermal conductivity, high surface area and excellent breathability, excellent light resistance and weather resistance, and durability. Disclosed is a method for producing a polyurethane nanofibrous skin material for automotive interior materials having a new (feeling resistance) and flame retardancy, which is different from existing synthetic leather.

Hereinafter, the manufacturing process of the skin material according to the present invention will be described in detail.

First, a spinning solution for producing a nanofiber web through a hybrid electrospinning process is prepared.

In the present invention, a spinning solution is prepared by solution polymerization using a mixture of polycarbonate diol and methylenediisocyanate (MDI) as a main material while using dimethylformamide (N, N-Dimethyl formamid; DMF) as a solvent. .

In this case, preferably, 1,4-butanediol can be polymerized by adding 1,4-butanediol as a chain extender, and 1,4-butanediol used as a chain extender is butanediol having a weight of 1 to 2 based on the polyurethane solids. Use wealth

Here, if less than 1 part by weight of the crosslinking is not enough, there is a problem in the heat resistance required in the subsequent laminating processing process, when used in excess of 2 parts by weight there is a problem that the properties of the polyurethane too hard (hard) It is preferable to use 1 to 2 parts by weight of the chain extender.

In addition, in order to obtain a conductivity suitable for spinning, anhydrous calcium chloride may be dissolved in the spinning solution in an amount of 0.1 to 0.5 parts by weight with respect to dimethylformamide, and if less than 0.1 parts by weight is added, there is a problem that the conductivity is low and the radioactivity is low. If it is added in excess of the amount, there is a problem that the polyurethane component in the spinning solution aggregates and precipitates, which is not preferable.

And, in preparing the spinning solution, it is possible to improve the surface properties of the nanofiber web by using a plasticizer, when the non-toxic citric acid ester plasticizer is added to 1 to 10 parts by weight based on the polyurethane solids surface ductility ( softness, wherein citric acid ester plasticizers include triethyl citrate, acetyl triethyl citrate, acetyl tributyl citrate and tri- Tri-n-propyl citrate and the like may be used.

Through the above process, finally, the content of polyurethane solids in the spinning solution is 10 to 20 parts by weight based on 100 parts by weight of the solvent, to prepare a spinning solution having a viscosity of 20,000 cps ± 2,000 of the spinning solution.

Here, if the polyurethane solid content is less than 10 parts by weight, the solvent does not volatilize during spinning, and if it exceeds 20 parts by weight, the viscosity of the spinning solution is so high that the fiber thickness of the obtained web reaches several microns. have.

The polyurethane spinning solution synthesized using dimethylformamide as a solvent and using polycarbonate diol and methylene diisocyanate as described above has excellent radioactivity and flame retardancy.

Next, the process of producing a nanofiber web by electrospinning the polyurethane spinning solution synthesized according to a specific composition and solid content ratio as described above, in a hybrid electrospinning system, without additional process such as molecular weight control, The urethane spinning solution is synthesized and directly electrospun to obtain a nonwoven nanofiber web continuously.

1 is a schematic diagram showing the configuration of a hybrid electrospinning system that can be used in the spinning process in the present invention, showing a process for producing a nonwoven nanofiber web using a hybrid electrospinning detention.

Hybrid electrospinning system as shown is disclosed in detail in Korean Patent Laid-Open No. 2006-25290, it will be briefly described with reference to this.

The state of the polymer solution (polyurethane spinning solution) spun through the spinning nozzle of the hybrid electrospinning tool 24 is a state in which the atomized spinning solvent and the micronized fiber in the form of filaments are mixed, and the ejection speed and the pressure are large. It decreases and moves toward the belt conveyor 27.

The atomized spinning solvent is volatilized to reach the belt conveyor 27 in a very unstable state, or is discharged to the solvent vapor recovery device 32 through the suction blower 26 connected to the belt conveyor 27, and finally The filamentary microfibers are seated on the belt conveyor 27 to obtain a nonwoven web.

The raw materials stored in the polymer storage tank 18 and the solvent storage tank are transferred to the dissolution and solution storage tank 21 to be completely dissolved, and then the gas (air) in the solution is completely removed through the gas removal apparatus 20.

If you do not remove the gas, the flow of the fluid will be uneven during spinning and cutting may occur, so the gas must be removed.

Thereafter, impurities and insoluble residues are removed through the solution filtration device 22 and then moved to the hybrid electrospinning detention 24 through the solution transfer device 23.

Fine fibers can be formed by the atomization of high-pressure air generated from the applied high voltage and the compressed air generating device 25 and ejected through the compressed air injection hole of the hybrid electrospinning tool 24. Can be.

The spun fine fibers are seated on the surface of the belt conveyor 27 connected to the suction blower 26 located below, and the fibers are ejected from the compressed air jetting hole of the hybrid electrospinning detonation and collide with the spinning fluid so that the fibers The collision with the surface at high speed can be prevented.

In addition, by laminating a low weight web through a cross molding machine, a high weight web can be obtained, and the uniformity of the web can be greatly improved through lamination, and various width adjustments are possible.

The web laminated through the cross molding machine is passed through a nip roll to remove static electricity present in the web through the static eliminator 29 and finally rolled through the fabric take-up device 30.

The vapor phase solvent generated during the spinning process is removed through the suction blower 26 and recovered through the solvent vapor recovery device 31.

As a radiation condition using the hybrid electrospinning system, the radiation voltage (applied voltage) is 40 to 50 kV, and the distance between the spinneret end of the electrospinning detention and the collector (belt conveyor) is 20 cm.

In addition, a spinning nozzle with a diameter of 0.5 mm and a diameter-to-length ratio (L / D) of 8/1 is used, and the spinning solution is maintained at a temperature of 30 to 60 ° C.

As described above, the nanofiber web obtained from the polyurethane composed of polycarbonate diol and methylene diisocyanate has excellent durability (wear resistance) and light resistance.

Next, when the polyurethane nanofiber web is obtained through electrospinning, the surface treatment is performed using a plasma surface treatment equipment to improve the surface properties.

In the present invention, the polyurethane nanofiber web obtained by electrospinning is subjected to plasma surface treatment using fluorine-based gas C ₂ F ₆ , and the surface treatment process can greatly improve the light resistance and additionally provide antifouling properties. It becomes possible.

The nanofiber web obtained as described above is adhered to a support using a flat-bed laminator 32 in a laminating process according to a conventional process to obtain a nanofiber skin material.

In this way, through the above process, the new sense of five sense fibers having superior surface area (surface resistance), light resistance, weather resistance, flame retardancy, etc. compared to conventional nanofibers, and has a high surface area and excellent breathability compared to conventional synthetic leather Can be prepared.

In particular, the polyurethane nanofiber skin material according to the present invention has the intermediate characteristics of the existing sheet-like skin material and non-woven skin material, the skin material for the headliner and sun visor, the skin material for the door casing, the sheet material for automobile interiors It is widely available as a material.

This invention will be described in more detail based on Examples. The present invention is not limited by the following examples.

[ Example  And Comparative example ]

-Spinning solution

The electrospinning material was NFR103, NFR106, UW8650, the solvent was DMF (N, N-Dimethyl formamid, ACROS Co., Ltd.), and the solution was prepared by adding CaCl ₂ (Calcium Chloride Anhydrous, SHINYO PURE Chemicals) to DMF. %) And the mixture was stirred for 1 hour with a solvent (wt%) and used for 1 hour.

Raw materials and solvents used in the samples are shown in Table 1 below.

* UW8650 is a polyurethane commonly used in the manufacture of leather

Table 2 and Figure 2 shows the viscosity and electrical conductivity change (calcium chloride content 0.1% by weight) according to the spinning solution composition.

Table 3 below is a table showing the spinning solution used in the experiment.

-Characterization and Analysis

Characteristic evaluation and analysis were conducted, and the maximum tensile strength, surface grade, abrasion resistance, and light resistance were evaluated. The maximum tensile strength, abrasion resistance, and light resistance were obtained from the static S / N ratio, and the surface grade (visual appearance). Evaluation) is a count value, so the tower pair count value S / N ratio was used.

a. Maximum tensile strength rating

As measurement conditions, five specimens of 20 × 50 mm in the MD and CD directions were taken, respectively, and ten measurements were taken per condition using the Universal Testing Machine (H100KS, HOUNSFIELD Co., Ltd.). Eight data except the minimum value were calculated.

The measurement results are shown in Table 4 below.

b. Fiber diameter measurement

As measurement conditions, the surface of the nanofiber web was measured using a scanning electron microscope (SEM) JEOL (JSM-6400), and the average diameter of the fibers was obtained.

The measurement results are shown in Table 5 below, and FIG. 3 is a scanning electron micrograph.

c. Wear Resistance Rating

As a measurement condition, the cycle until the complete destruction (number of revolutions until the hole was drilled) was calculated using a Martindale abrasion resistance tester and compared.

The measurement results are shown in Table 6 below.

      d. Light resistance evaluation

As test conditions, the light resistance test was performed using Atlas's Ci5000 Weather-O-meter (Xenon), and the color difference before and after the light resistance test was confirmed using GretagMacbeth COLOR-EYE 3100.

Table 7 shows test conditions, and Table 8 shows measurement results.

e. Surface grade evaluation

As an evaluation condition, four evaluators each presented nine samples of this experiment, graded through visual appearance evaluation, and the results were converted into numerical values (one point is the best).

Table 9 shows the evaluation results.

This difference in surface grade was measured by measuring the average fiber diameter of the surface of the nanofiber web using JEOL's JSM-6400 scanning microscope, showing that the smaller and uniform the fiber diameter, the better the appearance.

Table 10 shows the measurement results.

f. Plasma surface treatment effect

As the test conditions, nanofiber webs were surface treated using a CD 400 MC Plasma Surface Treatment System manufactured by Euoroplasma.

Test conditions and measurement results are shown in Table 11 and Table 12, respectively.

4 is a graph showing a color difference comparison before and after plasma surface treatment.

g. S / N ratio analysis

The underlined value is the highest value for each S / N ratio, which is the optimal condition for each characteristic value, and the final average S / N ratio is optimal because the number 1 is the largest S / N ratio considering three characteristics. It can be seen that the condition.

h. Analysis of variance

Variance analysis was performed to distinguish factors affecting the experiment, and the results are shown in Table 14 below.

Dispersion analysis shows that the tensile strength of the nanofiber web can be controlled by solution conditions, but the wear resistance, light resistance, and surface properties are affected by the polymer itself rather than by solution conditions.

The best experimental conditions were identified as Experiment No. 9 in terms of maximum tensile strength, Experiment No. 1 in terms of surface grade, Experiment Nos. 2 and 4 in wear resistance, and No. 7 in light resistance. In the case of experiment number 1 was found to be the best product.

The photo of the product obtained by laminating the polyurethane nanofiber web prepared under the conditions of Experiment No. 1 through the laminating process on the surface of the nonwoven fabric support used as the interior material for automobiles is shown in FIG. 5.

As described above, according to the method for manufacturing a light-resistant nanofiber skin material for automobile interior according to the present invention, by producing a nanofiber web using a hybrid electrospinning system and then performing a plasma surface treatment process as a post-processing, wear resistance and light resistance It is possible to manufacture nanofiber webs having excellent weather resistance and surface properties and skin materials for automobile interiors using the same.

The nanofiber coating material according to the present invention is a new tactile five sense fiber material, and has high surface area, excellent breathability, and unique surface structure and properties different from existing materials.

The nanofiber skin material prepared according to the present invention can be widely used as a material for car headliners and sun visors, door casing skins and sheets.

Claims (6)

In the method for manufacturing a highly durable nanofiber skin material for automotive interior using a hybrid electrospinning technology, A spinning solution was prepared by mixing polycarbonate diol and methylene diisocyanate as a main raw material, using dimethylformamide as a solvent, and mixing them with 1,4-butanediol as a chain extender to finally prepare a spinning solution. Preparing a spinning solution having a viscosity of 20,000 cps ± 2,000 with respect to 80 parts by weight of 10 to 20 parts by weight; Obtaining a non-woven polyurethane nanofiber web by electrospinning the spinning solution using a hybrid electrospinning cap; Improving antifouling and light resistance by plasma surface treatment; Adhering the obtained nanofiber web to a support through a laminating process; Method for producing a light-resistant nanofiber skin material for automobile interiors, comprising a. The method according to claim 1, 1,4-butanediol used as the chain extender is a method for producing a light-resistant nano-fiber skin material for automotive interior, characterized in that 1 to 2 parts by weight based on the polyurethane solids. The method according to claim 1, In preparing the spinning solution, 0.1 to 0.5 parts by weight of anhydrous calcium chloride is further dissolved in the dimethylformamide. The method according to claim 1, In preparing the spinning solution, 1 to 10 parts by weight of a citric acid ester-based plasticizer is further added to the polyurethane solids. delete The method according to claim 1, The electrospinning to obtain the polyurethane nanofiber web to plasma surface treatment equipment fluorine gas C ₂ F ₆ to 80sccm ± 16sccm range to a plasma surface treatment method of manufacturing automobile interior light resistance material nanofibers for skin characterized in that the input in.

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