KR101776170B1

KR101776170B1 - thermally expandable film, and method for manufacturing the same

Info

Publication number: KR101776170B1
Application number: KR1020160026642A
Authority: KR
Inventors: 유승훈; 박준홍; 유중철; 김용우
Original assignee: 주식회사 에스에이치글로벌
Priority date: 2016-03-04
Filing date: 2016-03-04
Publication date: 2017-09-11

Abstract

The present invention relates to a foamed film produced by applying a coating liquid containing a thermally expandable foamed capsule, a thermoplastic urethane resin adhesive and a solvent onto a substrate, followed by drying the foamed capsule-containing coating liquid, and a method for producing the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a foamed film and a method for manufacturing the same,

The present invention relates to a foamed film comprising a thermo-expandable foamed capsule and a method for producing the foamed film, and the foamed film can be used in an automotive interior material.

Recently, concern about the depletion of crude oil has put the national destiny in the development of alternative energy and prevention of serious environmental pollution. As a result, in the automobile industry, the use of polymer composite materials as a substitute for metals has been rapidly increasing as lightweighting has been promoted for the purpose of improving fuel efficiency of automobiles and exhaust gas emission, which is the main cause of environmental pollution. Until now, composite materials for automobile interior materials have been known as high-heat-resistant / high-rigidity composite materials reinforced with glass fiber, carbon fiber or the like as a reinforcing material in a polymer material such as polypropylene or thermoplastic olefin (TPO) (PET) resin and a thermosetting composite material through rubberization of a thermoplastic polymer have a performance exceeding that of a metal and are used for various purposes.

However, such fiber reinforced plastic (FRP) is unsatisfactory in terms of physical properties such as impact resistance and fracture toughness, has a small allowable deformation width at the time of material modification, and can not be recycled, .

Conventional head liner materials for automobiles include resin felt, paper board, glass fiber, natural fiber reinforced board, wood fiber hard polyurethane, Corrugated board and the like.

On the other hand, the resin foam has been used for various purposes because it can exhibit all properties such as heat resistance, heat insulation, sound insulation, sound-absorbing property, dust-proofing property and lightweight by changing the material and the state of bubbles formed. Examples of such a resin foam include a polyvinyl chloride or olefinic thermoplastic elastomer or the like on the surface of a foamed resin such as a foamed polyurethane, a foamed polypropylene, a foamed polyester or a foamed polyvinyl chloride obtained by foaming a chemical foaming agent A cushioning material made of a composite molded body obtained by adhering a fabric or the like as a skin material to such a resin sheet is used. In recent years, there has also been proposed a skin-attached foam obtained by injection molding a thermoplastic elastomer containing a chemical foaming agent and a resin for a skin using a cavity-moving method, instead of adhering a skin material.

However, the heat-decomposed chemical foaming agent inevitably generates foam residues at the same time as the decomposition gas, and the residue remaining in the molded body may affect the adhesion performance of the molded body. In addition, when a chemical foaming agent is used, there is a problem that it is difficult to obtain an expansion-molded article having a high airtightness because all of the bubbles do not become independent bubbles and inevitably become open bubbles.

The reason why the bubbles do not become independent bubbles is that the foaming power of the decomposition gas exceeds the melt tension of the resin because the viscosity of the resin is too low and the cell walls of the resin are destroyed. On the contrary, it has been attempted to produce an expanded molded article by using heat-expandable microcapsules instead of a chemical foaming agent.

Accordingly, the present inventors have found that the present invention can provide an automobile interior material and a headliner for automobiles which are capable of realizing environmental friendliness and light weight that are required by automobile manufacturers and the like at the present time and can secure price competitiveness and are excellent in dimensional stability, To provide various methods of applying thermo-expandable foam capsules to the material.

An object of the present invention is to provide a foamed film comprising a thermo-expandable foamed capsule applicable to various molded articles such as an automobile interior material and an automotive headliner material, a method for producing the foamed film, and a product formed using the foamed film.

A first aspect of the present invention is a method for producing a foamed capsule, comprising the steps of applying a coating liquid containing a thermally expandable foamed capsule, a thermoplastic urethane resin adhesive and a solvent onto a substrate and drying the coating liquid containing the foamed capsules, Wherein the weight ratio of the adhesive and the solvent is 4: 1 to 2: 4 to 6.

Wherein the coating liquid further comprises a curing agent and the content of the curing agent is 8 to 12 wt% of the content of the thermoplastic urethane resin adhesive.

In order to solve the problem that a loss due to powder scattering occurs when a conventional thermally expandable foamed capsule powder is applied to a natural substrate, the present invention provides a foamed article comprising a thermally expandable foamed capsule, a thermoplastic urethane resin adhesive, a curing agent, There is provided a foamed film produced by applying a capsule-containing coating liquid onto a substrate and then drying the coating liquid containing the foamed capsules.

The thermally expandable foamed capsule is composed of a core and a shell. The core containing a liquid hydrocarbon is accommodated in a shell containing a softenable thermoplastic polymer-containing capsule, and the temperature at which the liquid hydrocarbon in the foamed capsule is vaporized The capsules are expanded by the vaporization of the liquid hydrocarbon, and the foam capsules in the form of hollow balloons form independent bubbles, respectively.

Non-limiting examples of the softenable thermoplastic polymer include acrylonitrile, methacrylonitrile,? -Chlor acrylonitrile,? -Ethoxyacrylonitrile, a fumaronitrile copolymer, or any mixture thereof have. Preferably an acrylonitrile or methacrylonitrile copolymer.

By including the nitrile-based copolymer as the softenable thermoplastic polymer, heat-resistant properties of the heat-expandable foamed capsule can be improved, and foam molding can be carried out at a high molding temperature with a high expansion ratio.

Non-limiting examples of the liquid hydrocarbon included in the core of the heat expandable foamed capsule include ethane, ethylene, propane, propene, methylbutane, n-butane, isobutane, butene, isobutene, , Isopentane, neopentane, n-hexane, heptane, isooctane, petroleum ether and the like; Chlorofluorocarbons such as CCl ₃ F, CCl ₂ F ₂ , CClF ₃ , and CClF ₂ -CClF ₂ ; And tetraalkylsilanes such as tetramethylsilane, trimethylethylsilane, trimethylisopropylsilane and trimethyl-n-propylsilane. These may be used alone or in combination of two or more. Preferably, the liquid hydrocarbon may be isooctane or methyl butane.

Since the thermally expandable foamed capsules contain liquid hydrocarbons in the core, the heat-expandable foamed capsules do not easily break even under high-temperature and high-shear conditions at the time of molding, and can have excellent heat resistance.

The thermally expandable foamed capsules may comprise acrylonitrile copolymer, methyl butane, silica and water in one embodiment, and in another embodiment may comprise acrylonitrile copolymer, isooctane and water.

In the thermally expandable foamed capsule, the content of the core may be 10% by weight to 25% by weight based on the total weight of the foamed capsules. In the constitution of the foamed capsule, the thickness of the cell varies depending on the content of the core. However, if the content of the core is reduced to make the cell excessively thick, the foam performance deteriorates, and if the content of the core is increased, . When the content of the core is 10 wt% to 25 wt%, both the prevention of the collapse of the thermally expandable foam capsule and the improvement of the foam performance can be achieved.

On the other hand, the temperature for vaporizing the liquid hydrocarbon may be at or above the temperature at which the liquid hydrocarbon begins to thermally expand, and may preferably be the boiling point or more of the liquid hydrocarbon.

If the softenable thermoplastic polymer has a temperature higher than 240 ° C, the capsule particles made of the softenable thermoplastic polymer may be destroyed. Therefore, the temperature for vaporizing the liquid hydrocarbon is preferably 160 to 240 ° C. The boiling point of the liquid hydrocarbon is preferably 160 to 240 캜. Therefore, it is preferable that the liquid hydrocarbon starts to foam at 160 캜 and can expand to the maximum at 240 캜.

The maximum foaming temperature that can be expanded to the maximum means the temperature when the diameter of the thermally expandable foamed capsule is maximized (maximum displacement amount) when the diameter of the thermally expandable foamed capsule is measured while being heated from room temperature.

In the present invention, the thermally expandable foamed capsules are formed by core and shell formed by softening a shell containing a thermoplastic polymer capable of softening and expanding a liquid hydrocarbon in a core at a temperature higher than the foaming temperature of the liquid hydrocarbon, The foamed capsule may rapidly expand to form a hollow balloon (see FIG. 1). That is, each of the foam capsules in the form of a hollow balloon may form independent bubbles.

The present invention is characterized by using a matrix resin and a thermoplastic urethane resin as an adhesive in a coating liquid containing a heat-expandable foamed capsule.

The urethane resin as the thermoplastic adhesive has a strong adhesive force and has the advantage of not generating by-products during the reaction. In addition, it can be cured at room temperature, thereby improving production speed of film production and reducing cost. It has high impact resistance, but is excellent in flexibility and melts well in organic solvents and enables secondary molding.

In particular, the polyurethane resin has a wide selection range for isocyanate and polyol to be used together, and it is possible to design various types of products from soft to hard, from elastomer to foam, and has excellent mechanical strength such as tensile strength, tear strength and elongation abrasion resistance So that it is suitable as a matrix resin of an automobile interior material.

The present invention also relates to a foamed film containing foamed capsules, and further to a method for producing an automobile interior material, wherein the foamed capsule has its inherent physical properties (for example, proper (maximum) foaming at an appropriate temperature) Do not interfere. Since the thermoplastic urethane resin having good flexibility is re-fired at a temperature of at least 60 캜 to be completely softened, the urethane resins which may be covered or wrapped with the foamed capsules after the foamed capsules are mixed with the substrate, applied and dried, Or completely softened, thereby minimizing disturbance in foaming of the foam capsules. Further, since the thermoplastic urethane resin has a strong adhesive force, when the foamed capsules are cooled after they are foamed, the adhesiveness to the adhered material (for example, upper and lower natural fibers and foamed foamed capsules) is improved.

The thermoplastic urethane resin is preferably a thermoplastic urethane adhesive for hot melt processing in which the melting property is exhibited by heat.

The thermoplastic urethane resin may have a viscosity of from 500 to 10,000 mPas (cps), preferably from 6,000 to 8,000 cps at 25 占 폚. When the viscosity is less than 500 mPas (cps), the viscosity is low. For example, when the toner is poured into the space between the driving rollers, there is no mass productivity. When the viscosity is higher than 10,000 mPas (cps), the solvent is excessively introduced, .

The thermoplastic urethane resin preferably has a softening temperature of 60 to 85 캜 and excellent hot melt property. If the softening temperature is too low, it may be resistant to heat and may sticky during rolling after application to the substrate. If the softening temperature is too high, the temperature of the chamber must be increased or the production speed may be lowered, .

The type of the curing agent is not limited as long as it is a curing agent having an -OH group capable of reacting with the residual isocyanate (NCO) group at the terminal. The curing agent can exhibit excellent adhesion, heat resistance and water resistance through crosslinking with urethane resin. The urethane resin may exhibit a crosslinking reaction with a curing agent having an isocyanate group at the terminal thereof and having water or an OH group, and a curing agent for polyurethane is preferable. Particularly, a curing agent for a two-liquid solvent type polyurethane is preferable. Non-limiting examples of curing agents include water, polyols, glycols, amines, and the like

The viscosity of the curing agent may be from 500 to 10,000 mPas (cps) at 25 DEG C, preferably from 1,000 to 4,000 cps. If the viscosity of the curing agent is too low, the reaction and curing rate will be too fast, resulting in a large amount of precipitates of the foamed capsules after the blending, and if the viscosity is too high, mixing with urethane resin (viscosity: 500 to 10,000 mPas (cps) I can not.

On the other hand, the coating liquid containing the foamed capsules may contain an appropriate amount of solvent to uniformly disperse and dry the foamed capsule powder, the urethane resin and the curing agent.

The solvent is not limited as long as it is an organic compound capable of dissolving or mixing the components in the coating liquid containing the foamed capsules.

The solvent serves to dissolve or mix the components in the coating liquid containing the foamed capsules and is not limited to a kind of organic compound having a boiling point of 40 ° C to 160 ° C. However, it can be mixed well with, for example, alcohol, benzene and ether desirable. If the boiling point of the solvent is too low, the volatilization may be poor and the working conditions may be poor (for example, a strong odor may be generated in the field). If the boiling point is too high, the volatilization may not be performed well and harmful substances such as environmental hormones may remain. And may not meet the commercial conditions.

Non-limiting examples of the solvent include DMF (dimethyl formamide), MEK (methyl ethyl ketone), EA (ethyl acetate), toluene (toluene), MC (melamine cyanurate, melamine cyanate) , Or a combination of the above, and MEK or EA which is not too low or high in volatility in consideration of boiling point is preferable.

The present invention is characterized in that the weight ratio of the thermo-expandable foamed capsule, the thermoplastic urethane resin adhesive and the solvent is 4: 1 to 2: 4 to 6 in order to uniformly coat the coating liquid containing the foamed capsules on the substrate.

When the weight ratio of the thermo-expansible foam capsules is 4, and the weight ratio of the solvent is less than 4, the viscosity after blending becomes 2,000 cp or less, and the foam capsule precipitation rate per hour rapidly increases (see FIG. 5).

When the weight ratio of the thermo-expansible foam capsules is 4, the weight ratio of the solvent is more than 6, especially when the amount of the solvent is more than 2 times the amount of the foam capsules, the viscosity after the compounding is 9,000 cp or more and the settling rate of the foam capsules is remarkably reduced And is not precipitated even after lapse of 14 hours or more after mixing (see Fig. 6).

When the weight ratio of the thermo-expansible foam capsules in the weight ratio is 4, and the weight ratio of the urethane resin is more than 2, as shown in FIG. 7, normal foaming can not be performed due to the distribution and adhesiveness of the urethane resin surrounding the foam capsules .

The content of the hardener may be about 8 to 12% by weight of the thermoplastic urethane resin adhesive. Preferably about 10% by weight. When the content of the curing agent is less than 8% by weight, the curing rate is slowed and the production efficiency is lowered. If the content of the curing agent is more than 12% by weight, the curing rate is increased but the manufacturing cost is increased.

In one embodiment, the blend ratio of the thermo-expandable foamed capsule, the thermoplastic urethane resin adhesive, the curing agent and the solvent may be 4: 1: 0.1: 4 by weight.

A method of blending a foamed capsule-containing coating liquid is manual or screw-type.

A second aspect of the present invention is a method for preparing a foamed capsule, comprising the steps of: preparing a coating liquid containing a thermo-expandable foamed capsule, a thermoplastic urethane resin adhesive and a solvent; A second step of applying the above-mentioned foamed capsule-containing coating liquid onto a substrate; And a third step of drying the foamed capsule-containing coating liquid on the substrate.

The blend ratio of the heat expandable foamed capsule, the thermoplastic urethane resin adhesive and the solvent is preferably 4: 1 to 2: 4 to 6: 1.

The substrate to be coated with the coating liquid containing the foamed capsules may be a film or a nonwoven fabric, and may be in the form of a sheet.

Non-limiting examples of the substrate include polyolefin-based films (e.g., polypropylene, polyethylene, or a mixture thereof), EVA-based films, polyester-based films, and nylon-based films. The substrate may be a single layer or a multilayer. It is preferable to use a material capable of improving adhesion and strength with a headline nonwoven fabric in a future process.

There is a coating method in which knife, knife roll, and under roll are passed through a coating method and a spray method in which a predetermined amount is spread through a nozzle, in a system for uniformly applying a coating liquid containing a foamed capsule on a substrate.

The powder coating amount of the foamed capsule application layer may be 8 to 240 g / m ² , preferably 50 to 150 g / m 2.

Conventionally, when the foam capsule powder is directly coated on the base material, scattering of the foam capsule powder with a low specific gravity occurs, and the amount of application per unit area is not constant (see FIG. 9).

The present invention can apply a uniform foam capsule powder per unit area (see FIG. 10) since uniformly applying a coating liquid containing a foamed capsule on a substrate to produce a foamed film does not cause a problem of scattering.

The thickness of the substrate itself before application of the coating liquid containing the foam capsules is 40 to 80 占 퐉, and 160 to 220 占 퐉 after the application of the coating liquid containing the foam capsules. Preferably, the thickness of the substrate itself is about 40 占 퐉, and after application of the coating liquid containing the foamed capsules is about 160 占 퐉.

After applying the coating liquid containing the foamed capsules onto the substrate, it can be thermally dried in a chamber of 60 to 100 캜.

It is preferable that the railspeed in the chamber for drying 100% of the liquid urethane resin and the solvent after mixing and coating with the foamed capsules is 10 m / min to 15 m / min based on the chamber having the length of 25 m. If the speed exceeds 15 m / min, the film will not dry out and the resin may not be released or the film may be torn in the second post-rolling operation (roll-off operation) due to the adhesion of the resin. If it is less than 10 m / min, the productivity may be lowered and the cost may increase.

In one embodiment, the actual temperature in the chamber of 25 m section desired for the production of the foamed film is 75 캜. The chamber is divided into four sections, one section being at 65 ° C (preheating) and the second, third and fourth sections at 75 ° C. If the substrate used is a polypropylene film, the initial softening point may change from 80 ° C to a soft state, so that the film shrinks and is relaxed, the film is stretched in the chamber, and the thickness and weight of the product It may not be uniform or may be cut off, and the operation at 75 ° C or higher is not efficient. Further, at 75 DEG C or lower, the resin is not 100% dried.

Instead of the chamber, a heating roller or a heater bar may be used in the production of the foamed film of the present invention.

The foamed film of the present invention can be formed into a composite molded article by laminating a skin material on its surface, and can be processed into a secondary product or a tertiary product.

Examples of the skin material include ladder, resin film, woven fabric, and nonwoven fabric. As the skin material, a composite molding may be used which is made of natural leather or a silicone stamper with unevenness transferred from a stone or wood, and the surface is decorated with a lump or a grain. Or may be a composite body having a three-layer structure by forming a rigid foam layer as an aggregate. In the present invention, from the viewpoint of recycling and the like, it is preferable that the skin layer composed of the foamed layer and the skin material made of the expanded molded article is composed of a copper based thermoplastic elastomer.

In the foamed film of the present invention, the foamed capsules at the time of thermal expansion can be foamed at the time of preheating (at the passage of the oven) in the production of molded products. The foamed capsules are expanded by vaporization and expansion of the liquid hydrocarbon at a temperature higher than the foaming temperature of the liquid hydrocarbon, so that the foamed foamed capsules can form independent bubbles.

When manufacturing a head liner for an automobile using the foamed film of the present invention including the thermo-expandable foam capsule, the total weight of the head liner can be reduced to 800 g / m ² or less. When manufacturing a headliner for an automobile using the foamed film of the present invention including the thermally expandable foamed capsule, the diameter change of the foamed capsule before and after foaming is about 3 to 4 times, and the change of the volume is about 40 to 80 times .

The foamed film of the present invention may be applied to a multi-layer substrate and used as an automotive interior material, and a non-limiting example thereof may be an automotive headliner.

In one embodiment, a skin layer may be further laminated on at least one surface of the foamed film, followed by preheating and cold molding to form a molded article, which may be a package tray, a door trim, Such as a headliner, a seat back panel, a trunk trim, a rear window trim, and the like.

In addition, wall, ceiling material, flooring, etc., can be building interior material or ship interior material.

The foamed film according to the present invention is free from scattering due to mixing of the foamed capsule powder with the liquid urethane resin, solvent or the like, and the amount of the foamed capsule powder applied per unit area during the filming operation is uniform.

Since the foamed capsule powder according to the present invention is coated with the urethane resin on the substrate film, it does not cause scattering even when vibrating during the needling process, so that there is no loss and is economical. Further, there is no need for a separate application device necessary for applying the powder.

According to the present invention, the foamed capsules can be made into a film and can be applied to other substrates and rolls, which is convenient for application to multi-layer substrates.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing a foamed form of a thermally expandable foamed capsule used in an embodiment. FIG.
FIG. 2 is a SEM photograph showing the change of the foamed capsule powder before and after expansion according to the present invention. FIG.
FIG. 3 illustrates a manufacturing process of a foamed film according to an embodiment of the present invention.
4 is a photograph of a foamed film including a thermally expandable foamed capsule manufactured according to an embodiment of the present invention.
5 shows that the foamed capsule-containing coating liquid prepared in Comparative Example 1 of the present invention completely precipitated the foamed capsules after 1 hour from the start of the precipitation of the foamed capsules from 20 minutes after compounding.
Fig. 6 shows a phenomenon in which the filling port is clogged because the coating liquid containing the foamed capsules prepared in Comparative Example 2 of the present invention can not uniformly pass through the inlet port at a charging thickness of 160 m or less without being settled after 14 hours .
Fig. 7 shows that the foaming film produced in Comparative Example 3 of the present invention does not normally foam.
FIG. 8 shows that the foaming film produced in Example 3 of the present invention exhibited normal foaming.
FIG. 9 shows that the foaming capsule powder is scattered by applying the foam capsule powder directly onto the substrate in a conventional manner, and the amount of the coating per unit area is not constant.
FIG. 10 shows that uniform foam capsule powder was applied per unit area by preparing a foamed film according to the present invention.
Fig. 11 schematically shows before and after preheating of the foamed film of the present invention.
Fig. 12 schematically shows before and after preheating when the foamed film of the present invention is applied to a multilayer substrate.
13 shows that the foamed film prepared in Comparative Example 4 of the present invention does not normally coat the foamed capsules.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are for further illustrating the present invention, and the scope of the present invention is not limited to these examples.

Example 1: Preparation of foamed film

A foamed film was produced as shown in Fig.

Specifically, 20 kg of a foam capsule powder (MS2000D) purchased from the market, 5 kg of a thermoplastic urethane resin adhesive (product name: CA-7085K), 500 g of a polyurethane hardener (NEOFORCE CL-100) 20 kg (foamed capsules: thermoplastic urethane resin adhesive: hardener: solvent = 4: 1: 0.1: 4 weight ratio) was placed in an air mixer and uniformly mixed to prepare a coating liquid containing foamed capsules.

In the chamber of 25 m, the prepared foamed capsule-containing coating liquid was applied on a 40 탆 -thick three-layer structure polypropylene (PP) film (DCF-F). At this time, in order to adjust the thickness and weight, the gap between the knife roller and the under roller was adjusted, and the coating liquid was poured into the front board of the coater. A guide facility for width control was attached. After drying at a rail speed of 10 m / min in an oven at 75 DEG C, the thickness of the foamed capsule coating layer was 150 mu m and the application amount of the foamed capsule coating layer was 90 g / m < 2 >.

Example 2: Preparation of expanded film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1.75: 0.175: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

As shown in FIG. 8, normal foaming was performed.

Example 3: Preparation of foamed film

(Polyurethane hardener) (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1.5: 0.15: 4 to obtain a foam capsule powder F190D, a thermoplastic urethane resin adhesive (product name: CA-7085K) , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

Example 4: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 2: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

Example 5: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane curing agent (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

Example 6: Preparation of foamed film

(Trade name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate at a weight ratio of 4: 1: 0.1: 5 , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

Example 7: Preparation of foamed film

(A product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate in a weight ratio of 4: 1: 0.1: 6 , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

Comparative Example 1: Preparation of expanded film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

As shown in FIG. 5, since the foaming capsules are completely precipitated after 1 hour from the start of the precipitation of the foaming capsules from 20 minutes after the mixing, the foaming capsules are not uniformly coated when the coating liquid containing the foaming capsules is coated, It was not normally produced.

Comparative Example 2: Preparation of expanded film

(A product name: CA-7085K), a two-liquid solvent type polyurethane curing agent (NEOFORCE CL-100) and ethyl acetate in a weight ratio of 4: 1: 0.1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

As shown in FIG. 6, when the coating liquid containing the foamed capsules was coated on the film, due to the high viscosity of the coating liquid containing the foamed capsules, it was impossible to uniformly pass through the inlet with a thickness of 160 μm or less, And the injection port was clogged, and the foaming performance was remarkably reduced, so that the foam was not formed in a sufficient thickness and the strength was lowered.

Comparative Example 3: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 2.5: 0.25: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

As shown in FIG. 7, due to the distribution and adhesiveness of the foam capsules, normal foaming was not performed, and the foamed film was not formed in a sufficient thickness, resulting in a decrease in strength.

Comparative Example 4: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 0.8: 0.08: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE >

As shown in FIG. 13, the amount of the urethane resin was insufficient to normally coat the foam capsules, so that the foamed film was not normally produced.

Comparative Example 5: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE > As shown in Table 1 below, a foamed film was not normally produced.

Comparative Example 6: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE > As shown in Table 1 below, normal foaming was not carried out and the foamed film did not have a sufficient thickness.

Comparative Example 7: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 4: 2.2: 0.22: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE > As shown in Table 1 below, normal foaming was not carried out and the foamed film did not have a sufficient thickness.

Comparative Example 8: Preparation of foamed film

A commercially available foam capsule powder (F190D), a thermoplastic urethane resin adhesive (product name: CA-7085K), a two-liquid solvent type polyurethane hardener (NEOFORCE CL-100) and ethyl acetate were mixed at a weight ratio of 3.8: 1: , A foamed film was prepared in the same manner as in Example 1. The results are shown in Table 1. < tb > < TABLE > As shown in Table 1 below, a foamed film was not normally produced.

Experimental Example 1. Foaming of a foaming film

The change of the expanded film of Example 1 before and after expansion was analyzed by SEM photograph and is shown in Fig. The average diameter was changed from 30 to 40 占 퐉 before expansion, but the average diameter was 120 to 170 占 퐉 when foamed at 240 占 폚.

A (weight ratio) B (weight ratio) C (weight ratio) Presence or absence of foaming Presence or absence of coating Example 1 4 One 4 O O Example 2 4 1.75 4 O O Example 3 4 1.5 4 O O Example 4 4 2 4 O O Example 5 4 One 4 O O Example 6 4 One 5 O O Example 7 4 One 6 O O Comparative Example 1 4 One 3.8 O X Comparative Example 2 4 One 6.2 X O Comparative Example 3 4 2.5 4 X O Comparative Example 4 4 0.8 4 O X Comparative Example 5 4 One 3.5 O X Comparative Example 6 4 One 6.5 X O Comparative Example 7 4 2.2 4 X O Comparative Example 8 3.8 One 4 O X

A: Thermally expandable foam capsule

B: Thermoplastic urethane resin

C: Solvent (EA)

O: Not bad

X: Bad occurrence

In the case of Comparative Example 4, which contained less than 1 part by weight of the thermoplastic urethane resin, the foamed film was not normally produced, whereas in Comparative Example 3 and Comparative Example 7 which contained the thermoplastic urethane resin in a ratio exceeding 2 parts by weight, The strength of the foamed film was decreased due to insufficient formation of the thickness of the foamed film.

In Comparative Examples 1 and 5 containing less than 4 parts by weight of the solvent, the foamed film was not normally produced. On the other hand, in Comparative Example 2 and Comparative Example 6, which contained more than 6 parts by weight of the solvent, The strength of the foamed film was decreased due to insufficient formation of the thickness of the foamed film.

In the case of Comparative Example 8, which contained less than 4 parts by weight of the foamed capsules, the foamed film was not normally produced.

Experimental Example 2. Property Test

The flexural strength, flexural stiffness and flexural toughness of the foamed film prepared in Example 1 were measured and the results are shown in Table 2 below.

division Flexural strength (N) Flexural stiffness (N / mm) Flexural toughness (%) GMW 17251 spec 40 ± 10 10 ± 2 50? Final product 37.5 9.2 61.5

The bending strength, flexural rigidity and bending toughness of the final product of the foamed film were measured using the ISO 178 method. The specimen size was 200 mm (L) x 75 mm (W), support span was 100 mm, test speed was 50 mm / min Respectively. As a result, the foamed film of the present invention exhibited better values in flexural strength, flexural rigidity and flexural toughness than GMW 17251 spec.

Claims

A thermoplastic urethane resin adhesive, and a solvent, onto a substrate, and drying the foamed capsule-containing coating liquid,
Wherein the weight ratio of the heat expandable foamed capsule, the thermoplastic urethane resin adhesive and the solvent is 4: 1 to 2: 4 to 6.

The method according to claim 1,
Wherein the coating liquid further comprises a curing agent, and the content of the curing agent is 8 to 12% by weight of the thermoplastic urethane resin adhesive.

The method according to claim 1,
Wherein the thermally expandable foamed capsule is composed of a core and a shell, the core contains a liquid hydrocarbon having a foaming initiation temperature of 160 to 240 DEG C, and the shell contains a thermoplastic polymer capable of softening at the foaming initiation temperature A foamed film characterized by being a thermally expandable foamed capsule having a capsule.

The method of claim 3,
In the above heat-expandable foamed capsule, the content of the core is 10 wt% to 25 wt% based on the total weight of the foamed capsules.

The method according to claim 1,
Wherein the solvent is DMF (Dimethylformamide), MEK (Methyl ethyl ketone), EA (Ethyl acetate), Toluene, MC (Melamine cyanurate) or a mixture thereof.

The method of claim 3,
Wherein the softenable thermoplastic polymer is acrylonitrile, methacrylonitrile,? -Chlor acrylonitrile,? -Ethoxyacrylonitrile, a fumaronitrile copolymer or a mixture thereof.

A first step of preparing a coating liquid containing a thermally expandable foamed capsule, a thermoplastic urethane resin adhesive and a solvent;
A second step of applying the above-mentioned foamed capsule-containing coating liquid onto a substrate; And
A third step of drying the foamed capsule-containing coating liquid on the base material
The method of manufacturing a foamed film according to claim 1,

8. The method of claim 7,
Wherein the weight ratio of the heat expandable foamed capsule, the thermoplastic urethane resin adhesive and the solvent is 4: 1 to 2: 4 to 6.

8. The method of claim 7,
Wherein the coating liquid of the first step further comprises a curing agent, and the content of the curing agent is 8 to 12 wt% of the content of the thermoplastic urethane resin adhesive.

8. The method of claim 7,
Wherein the third step is carried out at 60 to 100 占 폚.

A molded article to which the foamed film of claim 1 is applied.

12. The method of claim 11,
Wherein the molded article is an automotive interior material.

12. The method of claim 11,
Wherein the molded article is an automotive headliner.