JPH05185567A - Recycle resin molded product and production thereof - Google Patents

Abstract

PURPOSE:To enhance mechanical strength by strongly bonding a sheet material to a recycle resin molded product even when the surface of the product is roughened by integrating a molded product main body composed of a thermoplastic resin containing a recycle resin with the sheet material composed of a thermoplastic resin by hot pressure molding. CONSTITUTION:Since a thermoplastic resin containing a recycle resin is reinforced by a fibrous reinforcing material 3, a recycle resin molded product 1 becomes high in mechanical strength as compared with a molded product only composed of a recycle resin. The fibrous reinforcing material uniformly incorporated in the gaps between the cured particles formed within the recycle resin to prevent the crack of the molded product between the particles. The interface of the molded product main body 4 with a sheet material 5 is roughened by the partially cured recycle resin but, by bonding the main body 4 to the bonding layer 7 of the sheet material 5, the molded product 1 having a uniform surface is obtained and the mechanical strength thereof is further enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin molded product using a recycled resin recycled from resin waste as a molding material, particularly a resin molded product suitable as a vehicle resin molded product, and a method for producing the same.

[0002]

2. Description of the Related Art Sprues, runners, defective moldings produced by thermoplastic resin injection molding, and defectives after surface treatment such as painting have been subjected to heat history once, Due to its limited use, it was generally discarded as resin waste material. However, from the standpoint of environmental protection and resource saving, it has been attempted to recycle a reusable portion from these resin waste materials as a recycled resin and use this as a molding raw material.

However, since such a recycled resin is subjected to a heat history, its physical properties, particularly mechanical strength, are deteriorated, and even if it is used as it is as a molding raw material, molding is performed.
The same physical properties as new resin cannot be obtained, and the physical property values vary. In addition, foreign matter such as dust is mixed in this recycled material, and there is a portion where the cured state becomes semi-permanent due to overheating when subjected to heat history, etc. Have difficulty. Even if molding is performed, the whole is not uniform, so the surface is roughened, there is no regularity in the degree of roughening, the back surface treatment such as painting is difficult, and the entire surface has a uniform roughness. A molded product with an excellent appearance cannot be obtained.

[0004]

The object of the present invention is to solve the above problems by fixing a sheet material made of a new resin on the surface of a molded product, thereby improving the mechanical strength of the molded product. And to obtain a recycled resin molded product having a uniform surface.

Another object of the present invention is to use a molding die which does not require surface precision of the die surface and to produce the above-mentioned recycled resin molded article easily and efficiently with low flow resistance. To obtain a method for producing a resin molded product.

[0006]

The present invention provides the following recycled resin molded product and its manufacturing method. (1) A molded article body made of a thermoplastic resin containing a recycled resin and a sheet material made of a new thermoplastic resin laminated so as to cover the surface of the molded article body are integrated by heat and pressure molding. A recycled resin molded product characterized by the following. (2) The molded product according to (1) above, wherein the molded product body contains a fibrous or powdery reinforcing material. (3) The molded product according to (1) or (2) above, wherein the sheet material is surface-treated. (4) A step of inserting a sheet material made of a new thermoplastic resin and having both front and back surfaces into a cavity of a molding die and arranging the surface so that the surface faces the die surface, and a thermoplastic resin containing recycled resin. Molding resin consisting of, a step of introducing between the back surface of the sheet material in the cavity and the other mold surface, the molding resin introduced is pressurized under a temperature of the softening point or more to fill the cavity, A method for producing a recycled resin molded product, comprising the step of forming a molded product main body and fixing the molded product main body to a sheet material. (5) The method according to (4) above, wherein the molding resin contains a fibrous or powdery reinforcing material. (6) The method according to (4) or (5) above, wherein the surface of the sheet material is surface-treated.

In the present invention, the recycled resin is a resin material which is recycled as a molding resin from a resin waste material. Such resin materials include sprue parts, runner parts, defective products produced by injection molding, defective products after surface treatment, thermoplastic resins such as trimmed end materials,
Examples include cured products of thermosetting resins and crushed products of reaction molded products.

In the present invention, the molding resin for molding the molded article body is a thermoplastic resin containing the above-mentioned recycled resin. Such a molding resin may be composed only of recycled resin, or may be a mixture of recycled resin and new resin. In either case, it is necessary to include a thermoplastic resin, and therefore, when the recycled resin is a thermosetting resin, it is used by mixing with another thermoplastic resin.

The above molding resin preferably contains a fibrous or powdery reinforcing material. Examples of the fibrous reinforcing material include short fibers such as glass fiber, carbon fiber, aramid fiber, and plant fiber, and whiskers such as silicon carbide, silicon nitride, potassium titanate, and aluminum borate. Examples of the powdery reinforcing material include talc, carbon black, silica and the like. Of these,
Fibrous reinforcements are preferred. When these reinforcing materials are mixed with a recycled resin in a state of being mixed with a new thermoplastic resin, the effect of improving the mechanical strength of the recycled resin is great.
The molding resin may contain other components in addition to these components.

In the present invention, the sheet material laminated on the molded article body is made of a new thermoplastic resin, but may contain other components. As the thermoplastic resin, one having a fixing property (welding property) with the recycled resin is preferable, and a resin of the same kind as the recycled resin is preferable. When the sheet material does not have adhesiveness, it can be adhered by forming an adhesive layer in advance on the back surface of the sheet material. It is desirable that the sheet material whose surface is colored is made opaque, or an opaque fixing layer is interposed between the sheet material and the molded article body so that the molded article body cannot be seen from the outside.

In the recycled resin molded product of the present invention, a molded product body made of a thermoplastic resin containing the recycled resin and a sheet material made of a new thermoplastic resin are integrated by heat molding. In heat molding, both resins are fixed and integrated by pressurizing at least part of the resin forming the molded product body and sheet material in a fluid state (including softening), such as injection molding and compression molding. A molding method involving heating and pressing can be adopted.

In the present invention, when a surface treatment such as painting is applied to a molded product, the sheet material may be surface-treated in advance. As surface treatment, in addition to spraying, dipping, painting by flow coating, etc., vacuum metallization by vapor deposition, sputtering, ion plating, etc.
Plating, hard coat treatment, etc. These surface treatments can be formed on the outer surface side of the sheet material,
It can also be formed on the molded product body side. When it is formed on the side of the molded article body, it is preferable to form a fixing layer having excellent adhesion to the molded article body. When the sheet material is transparent, the fixing layer may be an opaque colored layer to enhance decorativeness and to prevent the molded product body from being visually recognized from the outside.

[0013]

The recycled resin molded article of the present invention comprises a sheet material made of a new thermoplastic resin and having both front and back surfaces.
Insert it into the cavity of the mold and arrange it so that its surface faces the mold surface.A molding resin made of a thermoplastic resin containing recycled resin is placed between the back surface of the sheet material in this cavity and the other mold surface. It is manufactured by introducing and introducing the molding resin into the cavity by pressurizing the resin at a temperature equal to or higher than the softening point to form a molded article main body and at the same time, to fix and integrate the sheet material. In this case, the molding resin may be heated and introduced into the cavity in a flowable state, and may be held at a softening temperature or higher and pressurized, or after the molding resin is introduced into the cavity, heated to a softening temperature or higher. You may pressurize. When heating after introduction, high frequency heating can be used.

In the recycled resin molded product manufactured in this manner, the surface of the molded product body molded by the recycled resin is unevenly roughened, but the back surface of the sheet material and the surface of the molded product body are fixed to each other. As a result, the mechanical strength of the molded product is improved, and a recycled resin molded product having a uniform surface can be obtained.

In the above manufacturing method, since the surface of the molded product is determined in advance by the surface of the sheet material to be used, even if molding is performed using a molding die having low mold surface accuracy (high roughness). The surface roughness of the mold surface is less likely to be transferred to the surface of the sheet material, and a molded product with high surface accuracy (low roughness) can be obtained. Also, the recycled resin has low fluidity because the cured part remains partially, but when the sheet material is placed on the mold surface and the molding resin is introduced, the sheet material acts as a heat insulating layer and rapidly heats the molding die. Since it is less likely to be depleted, the rapid hardening of the resin is less and the flow resistance of the resin is smaller.
Therefore, the moldability is improved, and the molding can be easily performed.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a recycled resin molded product of the embodiment, FIG. 2 is a sectional view taken along the line AA, and FIG. 3 is a partially enlarged view thereof.

In the figure, reference numeral 1 denotes a recycled resin molded product, which is applied to a finisher as a vehicle resin molded product. In the molded article 1, a sheet material 5 made of a new transparent thermoplastic resin is integrated by heat molding on the outer surface side of a molded article body 4 made of a thermoplastic resin 2 containing a recycled resin and a fibrous reinforcing material 3, The whole is integrally molded in a container shape. The reinforcing material 3 is dispersed in a new resin and uniformly mixed with the recycled resin.

A display portion 6 is formed on the sheet material 5 by painting as a surface treatment layer on the back surface, that is, on the molded article body 4 side. Then, a fixing layer 7 made of an opaque colored layer is formed between the sheet material 5 and the display portion 6 and the molded product body 4, and fixed so as to be integrated with the molded product body 4.
Reference numeral 8 is a lock hole formed in the molded product 1.

Since the thermoplastic resin 2 containing the recycled resin is reinforced by the fibrous reinforcing material 3, the recycled resin molded article 1 has higher mechanical strength than that of the recycled resin alone. In this case, since the fibrous reinforcing material 3 is mixed with the recycled resin in a state of being uniformly dispersed in the new resin, the fibrous reinforcing material 3 uniformly enters between the hardened particles formed in the recycled resin and cracks between the particles. Etc. are prevented.

The interface of the molded article body 4 with the sheet material 5 is roughened due to the partially cured recycled resin, but by being fixed to the fixing layer 7 of the sheet material 5, the molded article having a uniform surface. 1 is obtained, and the mechanical strength is further increased.

Although the interface of the molded product body 4 is roughened,
It is blocked by the opaque fixing layer 7 and is not visible from the outside. Since the fixing layer 7 is colored, the decorative property is enhanced. Further, since the display portion 6 is visually recognized through the transparent sheet material 5, a deep display can be obtained.

4 to 11 are for showing the manufacturing method of the embodiment, FIG. 4 is a perspective view of a sheet material, FIG. 5 is a sectional view taken along the line BB, and FIGS. 6 and 7 are sheet material molded products. Cross section of the
8 is a perspective view thereof, and FIG. 9 is a C- of FIG. 8 showing an injection molding die.
A sectional view equivalent to C, and FIG. 10 is a sectional view equivalent to DD, FIG.
1 is a sectional view corresponding to CC in FIG. 8 showing an injection molded product.

To manufacture the recycled resin molded article 1, first, as shown in FIGS. 4 and 5, a display portion 6 is formed on the back surface side of a sheet material 5 made of a new thermoplastic resin by coating printing or the like, and further thereon. The fixing layer 7 made of an opaque colored layer is formed on the back surface side of the sheet material 5 including the above by coating or the like.

Next, the sheet material 5 is formed into a shape similar to or corresponding to the molded article 1 by vacuum forming, pressure forming, etc., to obtain a sheet material formed product 11 shown in FIG. Reference numeral 12 is a recess corresponding to the lock hole 8. This sheet material molded product 11 is trimmed while leaving a part of the flange portion 13 to the state shown in FIGS. 7 and 8.

The sheet material molded product 11 thus obtained is
As shown in FIG. 9 and FIG. 10, the sheet material 5 is inserted into the cavity 18 formed between the cavity mold 16 and the core mold 17 of the injection molding mold 15 so that the outer surface side of the sheet material 5 faces the mold surface 19 of the cavity mold 16. To place. In this state, the mold is clamped, and the recess 12 of the sheet material molded product 11 is inserted into the cavity mold 1.
6 and the core die 17 to fix.

Thereafter, the molding resin 21 made of the thermoplastic resin 2 containing the recycled resin and the fibrous reinforcing material 3 is heated and allowed to flow, from an injection nozzle (not shown),
It is injected from the runner 22 through the gate 23 between the back surface of the sheet material molded product 11 of the cavity 18 and another mold surface 20.
At this time, the molding resin 21 is pressurized by the injection pressure while being kept at a temperature equal to or higher than the softening point and filled in the cavity 18 to form the molded product body 4, and at the same time, the fixing layer 7 of the sheet material molded product 11 is formed. And fix it.

At this time, since the molding resin 21 contains the partially cured product of the recycled resin and the reinforcing material 3, the interface is roughened, but at least the back surface of the sheet material 5 and the fixing layer 7 are in a softened state, and molding is performed. Since the resin for press is pressure-bonded, both are fixed on the roughened surface. At this time, since the surface of the sheet material 5 does not soften as much as the back surface and maintains a certain degree of hardness, it is less affected by the rough surface of the interface of the molded product body, and the surface roughness of the molding die surface The degree of transfer is also low.

Since the injection-molded product 24 as shown in FIG. 11 is taken out by opening the mold, the recess 25 is formed by the punch 25.
By punching and trimming the flange portion 13 with the cutter 26, the recycled resin molded product 1 shown in FIGS. 1 to 3 is obtained.

In the above manufacturing method, since the surface of the molded product 1 is determined in advance by the surface of the sheet material 5 to be used, the mold surface 1
Even if molding is performed using the injection molding die 15 having a low surface accuracy (high roughness) of 9, the surface roughness of the mold surface 19 is rarely transferred to the surface of the sheet material 5, and thus the surface accuracy of A high molded product 1 is obtained. Further, the recycled resin usually has low fluidity because a cured portion remains partially, but when the sheet material 5 is placed on the mold surface 19 and the molding resin 21 is introduced, the sheet material 5 serves as a heat insulating layer. Since the hardening due to the rapid cooling of the resin is suppressed, the flow resistance of the resin becomes small. Therefore, the moldability is improved, and the molding can be easily performed.

In the above embodiment, in order to mold the container-shaped molded product 1, the sheet material 5 is preliminarily molded into the sheet material molded product 11, which is inserted into the molding die 15 to form the molded product body. 4 is performed, but when the molded product 1 has a flat plate shape or a shape close thereto, the molded product main body 4 can be molded without previously molding the sheet material 5.

Further, in the above embodiment, the sheet material 5 is fixed only to the outer surface side of the molded product, but if the back surface is also visible, the sheet material can be fixed to the back surface side as well. In this case, two sheet materials are arranged so that the front surface side of the sheet material 5 faces the mold surfaces on both sides of the molding die, and the molded article body is molded.

Further, in the above embodiment, an example in which the molded product main body is molded by injection molding is shown, but compression molding, injection compression molding, or other molding methods can be used. The present invention can be applied not only to molded articles for vehicles but also to other molded articles in general. In this case, the shape and structure of the sheet material can be determined according to each purpose, and the arrangement of the sheet material can be determined.

[0033]

As described above, the recycled resin molded article of the present invention comprises a molded article body made of a thermoplastic resin containing a recycled resin, and a sheet material made of a new thermoplastic resin.
Since it is integrated by heat and pressure molding, even if the surface of the molded product of recycled resin is roughened, it will stick to the sheet material,
This improves the mechanical strength of the molded product,
A recycled resin molded product having a uniform surface can be obtained.

Further, according to the method for producing a recycled resin molded product of the present invention, the sheet material is inserted into a molding die and is molded with the recycled resin in a state in which the surface of the sheet material faces the mold surface. Since resin is introduced and the molded product body is molded by pressurizing it at a temperature above the softening point, it is fixed to the sheet material at the same time. Thus, the recycled resin molded product as described above can be easily and efficiently manufactured.

[Brief description of drawings]

FIG. 1 is a perspective view of a recycled resin molded product of an example.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a partially enlarged view of FIG.

FIG. 4 is a perspective view of a sheet material.

5 is a sectional view taken along line BB of FIG.

FIG. 6 is a cross-sectional view of a molded sheet material.

FIG. 7 is a cross-sectional view of a sheet material molded product after trimming.

FIG. 8 is a perspective view of a molded sheet material.

9 is a sectional view corresponding to CC of FIG. 8 showing an injection molding die.

10 is a cross-sectional view corresponding to DD of FIG. 8 showing an injection molding die.

11 is a sectional view corresponding to CC of FIG. 8 showing an injection molded product.

[Explanation of symbols]

 1 Recycled Resin Molded Product 2 Thermoplastic Resin Containing Recycled Resin 3 Fibrous Reinforcing Material 4 Molded Product Main Body 5 Sheet Material 6 Display Part 7 Fixing Layer 11 Sheet Material Molded Product 13 Flange Part 15 Injection Mold 16 Cavity Mold 17 Core Mold 18 Cavity 19, 20 Mold Surface 21 Molding Resin 25 Punch 26 Cutter

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display B29K 105: 26

Claims (6)

[Claims] 1. A molded article body made of a thermoplastic resin containing recycled resin and a sheet material made of a new thermoplastic resin laminated so as to cover the surface of the molded article body are integrated by heat and pressure molding. Recycled resin molded product characterized by 2. The molded product according to claim 1, wherein the molded product main body contains a fibrous or powdery reinforcing material. 3. The molded product according to claim 1 or 2, wherein the sheet material is surface-treated. 4. A sheet material made of a new thermoplastic resin and having both front and back surfaces is inserted into a cavity of a molding die,
A step of arranging so that its surface faces the mold surface, and a step of introducing a molding resin made of a thermoplastic resin containing a recycled resin between the back surface of the sheet material in the cavity and another mold surface, Of the recycled resin molded product characterized by including a step of pressurizing the formed molding resin at a temperature equal to or higher than a softening point to fill the cavity to form a molded product main body, and at the same time, fixing the molded resin to a sheet material. Production method. 5. The method according to claim 4, wherein the molding resin contains a fibrous or powdery reinforcing material. 6. The method according to claim 4, wherein the surface of the sheet material is surface-treated.