KR101481217B1 - Multi-layered thin part molding of thermoplastic composite, forms using the same and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a multilayer thin plate of a thermoplastic composite material having a thin thickness and improved mechanical properties, a molded article formed by a high-temperature compression molding method of a multilayer thin plate of such a thermoplastic composite material, and a method of manufacturing the same.
The method for producing a molded article using the multilayered sheet of the present invention comprises the steps of: providing components of the multilayered sheet; Thermally bonding the components by a thermoforming method to form a multilayer laminate; And loading the multi-layer thin plate into a mold and performing high temperature compression molding to produce a molded article.
The present invention is advantageous in that a multilayer thin plate of a thermoplastic composite material is used to provide a molded article having a complicated structure having a thin thickness while achieving weight reduction.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layered thin plate of a thermoplastic composite material, a molded article using the same, and a method of manufacturing the same. [0002] MULTI-LAYERED THIN PART MOLDING OF THERMOPLASTIC COMPOSITE, FORMS USING THE SAME AND MANUFACTURING METHOD THEREOF,

The present invention relates to a multi-layer thin plate of a thermoplastic composite material, a molded article using the same and a method of manufacturing the same, and more particularly to a multi-layer thin plate of a thermoplastic composite material having a thin thickness and improved mechanical properties, And a method of manufacturing the same.

In recent years, plastic products have been used for replacing metal for the purpose of weight reduction. However, plastic products molded by injection molding using a resin are difficult to replace metals due to insufficient strength and rigidity.

For this reason, high-strength plastic products using composite materials mixed with reinforcing fibers such as glass fibers and carbon fibers are being used as substitutes for metals.

High-strength plastic products that are mixed with resin and reinforcing fiber are classified into thermoplastic resin and thermosetting resin depending on the characteristics of the resin, but the molding method is selectively used according to the characteristics of the injection and press method without distinguishing the characteristics of the resin.

Particularly, cases of products such as a mobile phone battery case, a notebook PC, a tablet PC, and a navigation device are becoming thinner and thinner. Accordingly, a typical molding method has been disclosed in Korean Patent Publication No. 2006-0045872 (published on May 17, 2006) And is a injection molding method using a composite material reinforced with a short fiber to a thermoplastic resin as described. Injection molding method is a good method to form a product with a complicated structure with an excellent surface quality. However, the thinner the thickness, the more limited the formability and the lower the basic physical properties, the more limited is the thinning of the final product.

The most commonly used materials for cell phone battery cases are composite materials reinforced with polycarbonate glass fibers. Based on the bending stiffness, which is the most typical property, the composite material reinforced with short fiber is 3.4 GPa, and the composite material reinforced with 70% polyamide has 19 GPa, which is about 5.6 times. This is not subject to the physical properties of the thin plate because of its high basic properties, and it can be thinned to 56% by an arithmetic method.

However, the composite material reinforced with continuous fibers can be formed only in a simple form such as a plate-like structure or a profile structure, but it can not be formed into a complicated structure having a thin thickness.

It is an object of the present invention to provide a multilayer thin plate of a thermoplastic composite material having a thin thickness and capable of improving mechanical properties to produce a molded article having a complicated structure.

Another object of the present invention is to provide a multi-layered thin plate of a thermoplastic composite material having the above objects, which is manufactured by molding a complex structure by a high-temperature compression molding method.

It is still another object of the present invention to provide a manufacturing method of forming a molded article using the multilayer thin plate of the thermoplastic composite material having the above objects.

According to an aspect of the present invention, there is provided a multilayer thin plate comprising: a base layer; A reinforcing layer provided on a lower surface of the substrate layer; And a resin layer provided on the upper surface of the base layer, wherein the base layer and the reinforcing layer are formed of a composite material containing glass fibers and resin in a predetermined ratio.

In the multilayer thin plate of the present invention, the base layer is formed in a laminated structure including 150 to 400 parts by weight of continuous fiber glass fibers in 100 parts by weight of a thermoplastic resin. The thermoplastic resin may be a polypropylene (PP), a polyethylene (PE) (polybutylene terephthalate), PA (polyamide), ABS (acrylonitrile butadiene styrene copolymer), and PC (polycarbonate) -ABS.

The molded article using the multilayer thin plate of the present invention comprises a base layer, a reinforcing layer provided on the lower surface of the base layer, and a resin layer provided on the upper surface of the base layer, wherein the base layer and the reinforcing layer are made of glass fiber and resin A multilayer thin plate formed of a composite material containing a predetermined ratio is formed by heat compression by a high-temperature compression molding method.

In the molded article using the multilayer thin plate of the present invention, the high-temperature compression molding method is characterized in that the multilayer thin plate is thermally compressed into a structure having a thickness of 0.1 to 5 mm at a high temperature by using a thermo-compression jig.

The method for producing a molded article using the multilayered sheet of the present invention comprises the steps of: providing components of the multilayered sheet; Thermally bonding the components by a thermoforming method to form a multilayer laminate; And loading the multi-layer thin plate into a mold and performing high temperature compression molding to produce a molded article.

In the method for manufacturing a molded article using the multi-layer thin plate of the present invention, the step of preparing the multi-layer thin plate includes: forming a base layer by pressing a laminate structure including 150 to 400 parts by weight of glass fiber with respect to 100 parts by weight of the thermoplastic resin; And 150 to 400 parts by weight of a thermoplastic resin relative to 100 parts by weight of short fiber or long fiber glass fiber.

In the method for manufacturing a molded product using the multilayer thin plate of the present invention, the step of producing the molded product may include thermally compressing the multilayered thin plate to a structure having a thickness of 0.1 to 5 mm at a high temperature of 300 to 400 ° C. do.

The present invention has the effect of providing a molded article having a complicated structure having a thin thickness and high bending rigidity while achieving weight reduction by using a multilayer thin plate of a thermoplastic composite material.

Further, according to the manufacturing method of the present invention, since the amount of flow is minimized as compared with injection molding, the residual stress after molding is reduced and the reliability of the product is high.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view of a multilayer laminate of a thermoplastic composite material in accordance with an embodiment of the present invention.
FIG. 2 is an exemplary view for explaining a molded article formed using a multilayer thin plate of a thermoplastic composite material according to an embodiment of the present invention; FIG.
3 is a flowchart for explaining a method of manufacturing a molded product using a multilayer thin plate of a thermoplastic composite material according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Here, the embodiments of the present invention can be modified into various other forms, and the scope of the present invention is not limited to the embodiments described below.

1, a multi-layer laminate 100 of a thermoplastic composite material according to an embodiment of the present invention includes a substrate layer 120, a reinforcing layer 110 provided on a lower surface of the substrate layer 120, And a resin layer 130 provided on the upper surface of the layer 120, and is formed to a thickness of 0.1 to 5 mm. In particular, the thickness is preferably 0.1 to 1 mm. When the thickness is less than 0.1 mm, the moldability is not good. When the thickness exceeds 5 mm, injection molding can also be performed, and there is no benefit in the high-temperature compression molding.

The base layer 120 is a layer showing the strength and rigidity of the multi-layered thin plate 100, and can be formed in a laminated structure containing a continuous fiber-shaped glass fiber and a resin in a predetermined ratio. Here, the base layer 120 may have a single layer or a laminated structure including 150 to 400 parts by weight of continuous fiber glass fiber in 100 parts by weight of the thermoplastic resin. The resin may be selected from thermoplastic resins selected from among polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), acrylonitrile butadiene styrene copolymer And may include one or more species.

At this time, when the glass fiber is less than 150 parts by weight based on 100 parts by weight of the thermoplastic resin in the base layer 120, it may be difficult to secure sufficient strength and rigidity. On the contrary, if the glass fiber is more than 400 parts by weight, .

The reinforcing layer 110 is provided on the lower surface of the base layer 120 to improve the strength and rigidity of the multi-layered thin plate 100. The reinforcing layer 110 may be composed of a composite in which a resin is added to short fiber or long fiber glass fiber. Here, the thermoplastic resin is contained in an amount of 150 to 400 parts by weight with respect to 100 parts by weight of short fiber or long fiber glass fiber.

The resin layer 130 may be provided on the upper surface of the base layer 120 to improve the dimensional feeling of the base layer 120 or to improve the dimensional accuracy of the print layer And the like can be easily formed by using a thermoplastic resin.

The multi-layer thin plate 100 of the thermoplastic composite material according to the present invention can improve strength and rigidity by using the reinforcing layer 110 and the base layer 120.

Therefore, as shown in FIG. 2, the multi-layered laminate 100 of a thermoplastic composite material can be made into a molding 200 of a complex structure having a thin thickness by a high-temperature compression molding method.

That is, the multi-layer thin plate 100 of the thermoplastic composite material according to the present invention is provided in a plate-like state, and the multi-layer thin plate 100 in the plate-like state is attached to a high temperature compression molding apparatus such as a thermo compression bonding jig,

2, the reinforcing layer 110 forms the inner surface, and the substrate layer 120 and the resin layer 130 are sequentially arranged in the outward direction, as shown in Fig. 2 (200). Here, the reinforcing layer 110 improves the strength and rigidity of the multi-layer thin plate 100, and makes it possible to form the molding 200 of a fine and complicated structure as shown in Fig.

Further, since the total thickness of the multi-layer thin plate 100 can be molded in a range of 0.1 to 5 mm by hot pressing, the molded product 200 can be manufactured to have a complicated structure with a thin thickness.

In addition, the high-temperature compression molding without the injection molding method minimizes the amount of flow in the molding process as compared with the injection molding, so that the finished molded product has a low residual stress and high reliability.

Hereinafter, a method of manufacturing a molded product 200 using a multi-layer thin plate 100 of a thermoplastic composite material according to another embodiment of the present invention will be described with reference to FIG. 3 is a flowchart for explaining a method of manufacturing a molded product using a multi-layer thin plate of a thermoplastic composite material according to another embodiment of the present invention.

According to another embodiment of the present invention, a method for manufacturing a molded product 200 using a multi-layered thin plate 100 includes first providing a plate-like material as a component of the multi-layered thin plate 100 (S310).

Specifically, the base layer 120 constituting the multilayer thin plate 100 of the present invention is first prepared. The base layer 120 may be formed by pressing a plurality of continuous glass fibers and thermoplastic resin layers in a laminated structure having 150 to 400 parts by weight of continuous fiber glass fibers per 100 parts by weight of the thermoplastic resin .

Apart from the base layer 120, the reinforcing layer 110 may include 150 to 400 parts by weight of a thermoplastic resin with respect to 100 parts by weight of short fiber or long fiber glass fibers, and the glass fiber may be impregnated with a thermoplastic resin .

The resin layer 130 may be formed separately from a thermoplastic resin film (not shown), or may be formed on the upper surface of the base layer 120 in a subsequent process.

After the base layer 120 and the reinforcing layer 110 are formed, the reinforcing layer 110 is thermally bonded to the lower surface of the base layer 120 by a thermoforming method to form a multi-layer thin plate 100 (S320) .

The thermoforming process is a process in which the thermoplastic resin is heated to a temperature at which the thermoplastic resin is in a fluid state. The thermoforming process includes, for example, stright vacuum forming, drape forming, matched mold forming ), And plug assist forming may be used.

The thermally forming method may be used to thermally bond the reinforcing layer 110 to the lower surface of the base layer 120 and to thermally bond the film layer made of the thermoplastic resin to the upper surface of the base layer 120, The resin layer 130 can be formed by applying a slurry.

At this time, the multi-layer thin plate 100 formed up to the resin layer 130 may be formed in a plate shape or a curved shape.

After the multi-layer thin plate 100 is formed by the thermoforming method, the multi-layer thin plate 100 is loaded on the mold and hot-pressed to produce a molded product (S330).

Specifically, the multi-layer thin plate 100 in a plate form is mounted inside a high-temperature compression molding apparatus such as a thermo compression jig or the like. The temperature of the multi-layer thin plate 100 is raised.

Accordingly, the reinforcing layer 110 of the multi-layer thin plate 100 is heated to a molten state in which the impregnated thermoplastic resin is fluid, and compression is performed in the state of the multi-layer thin plate 100 including the reinforcing layer 110. Here, since the thermoplastic resin of the reinforcing layer 110 is converted into a molten state having fluidity and compression is performed, it can be produced as a molded article 200 having a fine and complicated structure shown in FIG.

At this time, since the formed product 200 is compressed and formed at a high temperature state such as 300 to 400 占, it can be manufactured to have a complicated structure with a thickness of 0.1 to 5 mm.

Therefore, according to another embodiment of the present invention, the molded product 200 manufactured using the multi-layer thin plate 100 of a thermoplastic composite material can be made into a complicated structure having a thin thickness while being lightened.

In addition, the high-temperature compression molding without the injection molding method minimizes the amount of flow in the molding process as compared with the injection molding, so that the finished molded product has a low residual stress and high reliability.

Example  And Comparative Example

One. Example

Example  One

(1) Formation of base layer

150 parts by weight of glass fibers in a continuous fiber state were uniformly spread and heated to 100 parts by weight of polycarbonate and then heated to form a thermoplastic plastic-continuous fiber conjugate by joining glass fibers in a continuous fiber state and a tape-shaped polycarbonate, The joined body was folded in a zigzag form to make a multilayered thermoplastic-continuous fiber bonded body, and then the bonded body was pressed to prepare a base layer made of a thermoplastic-continuous fiber hybrid composite.

(2) Formation of a reinforcing layer

150 parts by weight of polycarbonate relative to 100 parts by weight of glass fiber of staple fiber is prepared, the glass fibers of the staple fiber are uniformly spread and heated, and then the glass fiber of the short staple fiber and the polycarbonate of the tape shape are bonded to each other, A short reinforcing layer composed of a thermoplastic-short-fiber hybrid composite was prepared by forming a short fiber joined body, folding the joined body in a zigzag shape to make a multilayered thermoplastic plastic-short fiber joined body, and then pressing the joined body.

(3) Formation of multilayer foil

A resin layer separately prepared for the surface quality with the base layer and the reinforcing layer is first molded into a plate-shaped material, then the plate-shaped material cut in a shape necessary for product molding is loaded into a mold, To prepare a composite multi-layer thin plate having a thickness of 0.1 mm.

Example  2

(1) Formation of base layer

Except that polypropylene was used in place of polycarbonate and 400 parts by weight of glass fiber in the continuous fiber state was used as 100 parts by weight of polypropylene.

(2) Formation of a reinforcing layer

The procedure of Example 1 was repeated except that polypropylene was used in place of polycarbonate and 400 parts by weight of polypropylene was used as compared with 100 parts by weight of short fiber glass fibers.

(3) Formation of multilayer foil

Using the prepared base layer and the reinforcing layer, a composite multi-layered laminate was produced in the same manner as in Example 1.

Example  3

(1) Formation of base layer

Polyethylene was used instead of polycarbonate, and the continuous fiber glass fiber was prepared in the same manner as in Example 1, except that 300 parts by weight of polyethylene was used as 100 parts by weight of polyethylene.

(2) Formation of a reinforcing layer

Polyethylene terephthalate was used instead of polycarbonate, and 300 parts by weight of polyethylene terephthalate was used as 100 parts by weight of short fiber glass fibers.

(3) Formation of multilayer foil

Using the prepared base layer and the reinforcing layer, a composite multi-layered laminate was produced in the same manner as in Example 1.

Example  4

(1) Formation of base layer

A polyamide was used in place of the polycarbonate, and glass fibers in a continuous fiber state were prepared in the same manner as in Example 1, except that 200 parts by weight of the glass fiber in 100 parts by weight of the polyamide was used.

(2) Formation of a reinforcing layer

ABS resin was used in place of polycarbonate, and 200 parts by weight of ABS resin was used in comparison with 100 parts by weight of short fiber glass fiber.

(3) Formation of multilayer foil

Using the prepared base layer and the reinforcing layer, a composite multi-layered laminate was produced in the same manner as in Example 1.

2. Comparative Example

150 parts by weight of glass fiber was mixed with 100 parts by weight of the molten polycarbonate resin and injection molded to produce a multilayer laminate of 0.1 mm in thickness.

3. evaluation

Formability Flexural stiffness Residual stress after molding
(Relative ratio to injection molding) Example 1 Excellent 19 GPa 71% Example 2 Excellent 19.2 GPa 69% Example 3 Excellent 18.3 GPa 74% Example 4 Excellent 19.5 GPa 65% Comparative Example Difficult to mold due to thin thickness 3.4 GPa 100%

As can be seen from Table 1 showing the experimental results, according to the embodiment of the present invention, by using the high-temperature compression molding method, the bending rigidity is about 5 times higher than that of the comparative example . Assuming that it has the same properties, it led to a thinning of about 56%.

Further, according to the embodiment of the present invention, since the amount of flow is minimized as compared with the injection molding of the comparative example, problems such as residual stress after molding are reduced.

Although the technical idea of the present invention has been specifically described according to the above preferred embodiments, it is to be noted that the above-described embodiments are intended to be illustrative and not restrictive.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention.

100: multi-layer thin plate 110: reinforcing layer
120: base layer 130: resin layer
200: Molding material

Claims (15)

A base layer;
A reinforcing layer provided on a lower surface of the substrate layer; And
A resin layer provided on an upper surface of the substrate layer;
In the multi-layer thin plate,
The base layer is formed of a composite comprising a glass fiber and a resin in a continuous fiber state.
Wherein the reinforcing layer is formed of a composite comprising short fiber or long fiber glass fiber and resin,
Wherein the multi-layer thin plate is formed by high-temperature compression molding so that the residual stress after molding is 75% or less of the residual stress at the time of injection molding and the bending rigidity is 18.3 GPa or more.
The method according to claim 1,
Wherein the base layer comprises 150 to 400 parts by weight of continuous fiber glass fibers in 100 parts by weight of the thermoplastic resin.
The method according to claim 1,
Wherein the reinforcing layer is formed of a composite comprising 150 to 400 parts by weight of a thermoplastic resin with respect to 100 parts by weight of short fiber or long fiber glass fiber.
The method according to claim 2 or 3,
The thermoplastic resin may be at least one of polypropylene (PP), polyethylene (PE), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polyamide (PA), acrylonitrile butadiene styrene copolymer (ABS), and polycarbonate Features multi-layer laminate.
The method according to claim 1,
Wherein the multi-layer thin plate is formed to a thickness of 0.1 to 5 mm.
delete A multilayer thin plate comprising a substrate layer, a reinforcing layer provided on a lower surface of the substrate layer, and a resin layer provided on an upper surface of the substrate layer,
Wherein the base layer is formed of a composite comprising glass fibers and a resin in a continuous fiber state and the reinforcing layer is formed by thermally compressing a multi-layer thin plate formed of a composite containing short fiber or long fiber glass fiber and resin by a hot compression molding method By mass or less, and 75% or less of the residual stress at the time of injection molding, and the bending rigidity is 18.3 GPa or more.
8. The method of claim 7,
Wherein the hot compression molding method thermo-compresses the multilayer foil at a high temperature using a thermo-compression jig to a structure having a thickness of 0.1 to 5 mm.
8. The method of claim 7,
Wherein the base layer contains 150 to 400 parts by weight of glass fibers in a continuous fiber state with respect to 100 parts by weight of the thermoplastic resin,
Wherein the reinforcing layer is formed of a composite comprising 150 to 400 parts by weight of a thermoplastic resin with respect to 100 parts by weight of short fiber or long fiber glass fiber.
delete Providing a substrate layer formed of a composite in which a laminated structure including glass fibers and a resin in a continuous fiber state is formed by compression;
Providing a reinforcing layer formed of a composite comprising a short fiber or long fiber glass fiber and a resin;
Forming a multi-layer thin plate by thermally bonding the base layer and the reinforcing layer by a thermoforming method;
Loading the multi-layered thin plate into a mold and performing high-temperature compression molding to produce a molded product;
/ RTI >
Wherein the multilayer thin plate is formed by high temperature compression molding so that the residual stress after molding is 75% or less of the residual stress at the time of injection molding and the bending rigidity is 18.3 GPa or more.
12. The method of claim 11,
The base layer is formed by pressing a laminate structure including 150 to 400 parts by weight of continuous fiber glass fibers in 100 parts by weight of a thermoplastic resin,
Wherein the reinforcing layer is formed of a composite material comprising 150 to 400 parts by weight of a thermoplastic resin with respect to 100 parts by weight of short fiber or long fiber glass fiber.
13. The method of claim 12,
The step of providing the base layer
And forming a resin layer on the upper surface of the substrate layer. ≪ RTI ID = 0.0 > 11. < / RTI >
12. The method of claim 11,
The step of producing the molded article
Layered thin plate is thermally compressed into a structure having a thickness of 0.1 to 5 mm at a high temperature of 300 to 400 DEG C by using a thermo-compression jig.
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