JP3031357B1 - Sandwich molded products containing recycled materials - Google Patents

Abstract

Abstract: [PROBLEMS] To increase the content of recycled materials in a molded article;
Another object of the present invention is to enable the molded article to be reused as a recycled material of the same product. SOLUTION: In a sandwich molded product comprising a core material and a surface material covering the entire surface of the core material, a regenerated material is contained in both the surface material and the core material, and the resin of the surface material and the resin of the core material are the same. Sandwich molded product composed of resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION In order to recycle a recycled material into a product, when mixing the recycled material with an unused material, (1) increase the content of the recycled material due to foreign matter in the recycled material and problems in physical properties. Want to increase the content despite difficulties, (2)
Want to reuse molded articles for similar products again.
The present invention is useful when the expectation (2) is also required.

[0002] If used for such purposes, the type of product is not particularly limited, but the parts of electrical and electronic equipment must satisfy the flame retardancy standard. Rather, it is a requirement to make it easier to obtain standards by making the types of flame retardants the same, and use in such products is particularly useful.

[0003]

2. Description of the Related Art Sandwich molding and molded articles are known, and there are many reports on mold techniques and molding techniques for effectively performing sandwich molding. As for sandwich molded products, application of sandwich molding to various products such as automobile parts and home electric appliances has been attempted. The purpose of applying the sandwich molding is to use a material having a specific function such as an electromagnetic shielding material or a foam material as a core material, and to impart a specific function without significantly changing the appearance and physical properties of the product. Recycled materials often have defects in quality, but it is a generally known idea to use this as a core material and to use a new material as a surface material to obtain a product having no problem in appearance.

[0004] The conventional idea is to use a recycled material as a core material as described in the preceding section. In other words, since recycled materials are generally obtained from products after use, removal of adhered dirt is a problem.If sandwich molding is used only for the core material and if a new material is used for the surface material,
Even if there is dirt, it can be hidden inside and a molded article whose surface is no different from a molded article molded from only a new material can be obtained.

[0005] In a more extreme case, as the core material, a material different in color from the surface material, a material from another product, a material containing foreign matter, etc. can be used as long as it can be molded.

[0006]

If you try again recovered using However, such a molded article [0006], the case except that the use and thermal recycling to low-quality molded articles difficult in many cases. In the case of electrical and electronic equipment, it may be necessary to obtain flame retardancy standards, and it is necessary to control the type and content of the resin and flame retardant contained in the surface material and core material. It is difficult to use the molded product again for a molded product of the same product only with the concept of using a recycled material for sandwich molding.

[0007]

The feature of the present invention is that the recycled material is used also for the surface material, and the content of the recycled material in the whole molded product is reduced as compared with the case where the recycled material is used only for the conventional core material. At the same time, the content of the recycled material may be different between the surface material and the core material, but other than that, the same type of resin is used, and a molded product that is easy to material-recycle again to the same type of product is provided. On the point.

Here, the same kind of resin means not only the kind of the resin but also the kind of the flame retardant, and preferably the same kind of material having the same color tone. If such a material is used for the surface material and the core material, the molded product is crushed and washed, then a small amount of a coloring material, a flame retardant, etc. are added, and further, the physical properties, flame retardancy, color tone are obtained by kneading with an unused resin. It is possible to prepare a recycled material-containing pellet which is almost the same as the original resin brand (in the present invention, this is referred to as a resin of the same kind) and use it again for a molded article of the same kind of product.

In recent years, disposal of waste products has become a social problem due to environmental problems, and it has become necessary to use it as energy for thermal recycling and to reuse it as a material for material recycling.

[0010] As for material recycling, there is a method of using it for other products whose quality may be low, but it is desirable to reuse it for the same product if possible. In order to reuse the same product, it is required that the material is free from contamination and that the physical properties do not deteriorate.

In particular, electric and electronic equipment often requires the UL flame retardant standard of the United States. When a recycled material is used for a plastic casing to be used, not only the type of resin but also additives such as a flame retardant are used. The type also needs to be constant.

When the recycled material is reused, if the recycled material pellets obtained through post-processing such as sorting, crushing, washing, and drying from the used waste product are free from dirt and physical properties, they are directly formed into products. It can be reused, but in many cases the dirt is not sufficiently removed, and it is necessary to partially mix the recycled material with at least half of the unused new material. Is difficult.

In such a case, according to the sandwich molding method, a mixed material with an unused new material is used for a surface layer of a molded article, and a 100% recycled material itself is used for a core layer (core portion). Can be used to increase the usage ratio of the recycled material.

Further, the surface layer (the material in this portion is referred to as a surface material) and the core layer (the material in this portion is referred to as a core material) are provided with a content ratio of a recycled material (in a mixture of the recycled material and an unused new material). Only the percentage of recycled material) and the same type of resin, flame retardant, etc. (the same type of material) can be used. The material conforms to the UL flame retardant standard that has been applied as a material of the product, and can be recycled as it is and used for the same product.

The gist of the present invention is that in a sandwich molded article comprising a core material and a surface material covering the entire surface of the core material, both the core material and the surface material contain recycled materials, and only the content ratio of the recycled materials differs. It is an object of the present invention to provide a molded article that aims to increase the content of a recycled material and recycle the material again by using the same kind of resin.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described more specifically. The type of the resin of the surface material and the core material of the sandwich molded product of the present invention is not particularly limited, but polyolefins such as polyethylene and polypropylene, impact resistance modifying materials of polyolefins by rubber components, polyvinyl chloride, polystyrene, impact resistance Improved polystyrene, acrylonitrile-styrene copolymer, acrylonitrile-styrene-butadiene copolymer (ABS resin), polycarbonate,
Polycarbonate-ABS resin alloy polymer, Polycarbonate-Polystyrene alloy polymer, Polycarbonate-Polyester alloy polymer, Polycarbonate-Polyamide alloy polymer, Modified polyphenylene ether resin, Mixture with the same polystyrene, Polyamide such as nylon, Alloy polymer containing polyamide , Polyoxymethylene, polyethylene terephthalate, polybutylene terephthalate, various liquid crystal polymers, and the like. Desirable resins are high-impact polystyrene, ABS resin, modified PPO, polycarbonate, polycarbonate-ABS resin alloy polymer, polycarbonate-polystyrene alloy polymer, and other materials normally used for the housing of electric and electronic equipment.

The resin used in the present invention is a UL94 (Underwriters Laboratories) flame retardant standard of the United States.
HB, UL94V-2, UL94V-1, UL94V-
0, UL945V, or any other material.

In the case of the flame retardant material, the flame retardant contained in the material is not particularly limited, but it is supervised by Sanko Shuppan Co., Ltd.
Brominated, chlorine-based, phosphorus-based and inorganic flame retardants described on pages 2 and 13 and silicone-based flame retardants which are not described in this document are exemplified. Of course, the material of the present invention also includes resins containing no flame retardant, coloring materials, inorganic fillers, glass fibers, carbon fibers, and other additives containing additives other than flame retardants.

The resin used in the present invention is characterized in that, in the case of a mixture of a core material and a surface material with a new material, the recycled material and the new material are the same type of resin. The same kind here means that when mixing non-flame-retardant resins and when mixing non-flame-retardant resin and flame-retardant resin, the type of resin is the same, and when mixing flame-retardant resins, The type of flame retardant means the same material.

Further, the same material is used for the core material and the surface material, and the same meaning here is the same as described above. That is, when both the core material and the surface material are non-flame-retardant resins and when one is a flame-retardant resin, it means that only the type of resin is the same, and when both are flame-retardant resins, the type of resin and the type of flame retardant Mean the same thing. However, the content of the recycled material may be the same, but usually differs between the core material and the surface material, and the content of the recycled material in the core material is higher. [Ratio of core material and surface material] The ratio of the core material and the surface material is not particularly limited, but usually, when the total of the core material and the surface material is 100 parts by weight, the core material is 10 to 40 parts by weight. is there. When the thickness of the molded product is large, the core material can be encapsulated in a large amount, so that the ratio of the core material can be larger than 40 parts by weight. On the other hand, the ratio of the surface material becomes small. Even without using recycled materials, the content of recycled materials can be increased only by the core material, so it is more advantageous to use unused new materials that do not have to worry about dirt on the surface material because there is no problem such as dirt It is.

When the ratio of the core material is less than 10 parts by weight, the significance of sandwich molding is small, and
The content of the recycled material is not much different from the case where the material containing 0% by weight is molded by ordinary injection molding. For the above reasons, the ratio of the core material is usually 10 to 40 parts by weight, but when the wall thickness is about 3 mm as in the case of electric and electronic products, the ratio of the core material substantially corresponds to this range. . [Rate of recycled material in core material] The ratio of recycled material in the core material is 30.
% By weight to 100% by weight. To increase the content of recycled materials, 100% by weight is desirable. However, in order to recycle the molded product again, the color is adjusted and a flame retardant is added. In some cases, it may be necessary to add several tens of percent of a drug or a new material for reinforcing physical properties, and the range is 30% to 100% by weight. [Ratio of Recycled Material in Surface Material] The ratio of the recycled material in the surface material is 5% by weight to 50% by weight. 50% by weight in the surface material
If the material does not have a problem such as contamination even if a larger amount of recycled material is contained, the content of the recycled material in the molded product can be increased even by ordinary injection molding, and it is not necessary to adopt sandwich molding. . 5% by weight of recycled material in the surface material
When the amount is smaller, the use of a new material is less likely to cause problems such as dirt than the use of a recycled material in the surface layer in order to increase the content of the recycled material in the molded article. Therefore, the range is 5% by weight to 50% by weight. [Molding method] The molded article of the present invention can be molded by a molding method usually carried out as sandwich molding in the field of plastics.

As shown in FIG. 1, in the sandwich molding method, first, the material of the surface layer (surface material 2) is supplied from the injection port 4.
After the injection , the material of the core layer (core material 1) is injected and injected from the injection port 4, and finally a small amount of the material of the surface layer is injected from the injection port 4. About this sandwich molding method,
For example, “Synthetic resin” Vol. 39, no. 9 (1993
September issue), page 17, page 21.

Hereinafter, the method of preparing the materials will be described first, and then the present invention will be described in detail with reference examples, examples, and comparative examples. However, the scope of the present invention is limited to the contents of these examples. is not. In addition, the UL flame-retardant standard of the material omits UL94, and indicates 1/12 ″ indicating the thickness of the molded product.
(1/12 inch) and add 1/12 "HB, 1/1
2 "V-0. [Preparation of material (1)] Waste products of a specific type of desktop personal computer manufactured by NEC Corporation were collected, and flame retarded polystyrene (U.S. UL flame retardant standard 1 / 12 "V-0 product)
The display casings made of the above materials were sorted out, and different kinds of materials such as paper labels and metal labels attached to them were removed.

Further, these are crushed and washed, and then toned and pelletized with a kneading machine, and UL Flame Retardant Standard 1/12 "V-0.
White recycled pellets were obtained. This recycled material pellet is referred to as a material A100. This is a material composed of 100% recycled material, except for a small amount of new additives such as coloring materials. Material A
As a result of preparing 100 test pieces and observing the foreign substances and measuring the physical properties, the number of black foreign substances (radius of 100 μm or more) per 0.1 m 2 of the surface area of the test pieces was evaluated as three. Izod impact strength (ASTMD25
6) was 8.5 kgf · cm / cm 2. [Preparation of Material (2)] A back plate of a polystyrene keyboard and a front mask (a plastic cover at the front of the casing of the personal computer main body) were collected from waste products of a desktop personal computer manufactured by NEC Corporation.

These are U.S. UL flame retardant standards 1/12 "H
It was a non-flame-retardant material of Product B, and included products using polystyrene from several material manufacturers.

From these, excluding attached materials made of dissimilar materials such as paper labels, metal labels, rubber materials and acrylic materials,
After crushing and washing, add the same flame retardant and colorant as the flame retardant polystyrene of the waste product, and use a kneading machine to UL Flame Retardant Standard 1
/ 12 "V-0 white recycled material pellets. The recycled material pellets are referred to as material B100.

This is a material composed of 100% recycled material except for additives such as newly added flame retardants and coloring materials.
As a result of preparing a test piece of the material B100 and observing the foreign substance and measuring the physical properties, the contamination of the material was 0.1% in the surface area of the test piece.
The number of black foreign substances (radius 100 μm or more) per m 2 was estimated to be 10, and Izod impact strength (ASTM)
D256) was 3.5 kgf · cm / cm 2. [Preparation of material (3)] The material was prepared in the same manner as in the preparation of material (2) except that the backing plate and the front mask of the keyboard were freed of the adhering material made of a different material, crushed, and the washing step was omitted.
A white recycled material pellet having an L flame retardancy standard of 1/12 ″ V-0 was obtained. This recycled material pellet is referred to as a material C100. This material is also made of 100% recycled material except for additives.
As a result of preparing a test piece of the material C100 and observing foreign matters and measuring physical properties, the stain on the material was 0.1% in the surface area of the test piece.
The number of black foreign substances (radius of 100 μm or more) per m 2 was evaluated as 100, and the Izod impact strength (AST
MD256) was 3.5 kgf · cm / cm 2. [Preparation of material (4)] In preparation of material (1) , when preparing regenerated material pellets with a kneading machine, 67 parts by weight of a new unused UL flame-retardant standard 1/12 "V-0 polystyrene was used. , Crushed, washed and mixed with 33 parts by weight of material from waste products, containing UL materials containing 33% by weight of UL flame retardant standard 1/1
2 "V-0 white recycled material pellets were obtained.

This recycled material pellet is referred to as material A033. As a result of preparing a test piece of the material A033 and observing the foreign substances and measuring the physical properties, the number of black foreign substances (radius of 100 μm or more) per 0.1 m 2 of the surface area of the test piece was evaluated as one, In addition, Izod impact strength (AS
TMD256) was 9.5 kgf · cm / cm2. [Preparation of Material (5)] When preparing regenerated material pellets by a kneader in the preparation of material (2) , a new unused UL flame-retardant standard 1/12 ″ V-0 polystyrene 90 is used.
Parts by weight are mixed with 10 parts by weight of the material from the crushed and washed waste products, and UL flame-retardant standard 1/12 "V-0 white recycled material pellets containing about 9% recycled material slightly less than 10% by weight I got

This recycled material pellet is referred to as material B009. As a result of preparing a test piece of material B009 and observing foreign substances and measuring physical properties, the number of black foreign substances (radius 100 μm or more) per surface area of 0.1 m 2 of the test piece was evaluated as one as to contamination of the material. In addition, Izod impact strength (AS
TMD256) was 9 kgf · cm / cm2. [Unused new material] For comparison, it is necessary to know the cleanness and physical properties of the unused new material, and the measurement was performed on polystyrene (UL flame-retardant standard 1/12 "V-0).
The degree of no contamination on the surface of polystyrene (UL flame-retardant standard 1/12 "V-0) is 0 to 1 when evaluated based on the absence of black foreign matter per 0.1 m @ 2, which is the maximum allowable. Also one
It is estimated to be about one. Izod impact strength is 10k
gf · cm / cm 2. [Reference Example 1 Sandwich molding (1)] The material A033 (white) described in [Preparation of material (4)] is used as a surface material, and the material A100 described in [Preparation of material (1)] is colored black (sandwich). A technically important point in molding is to avoid exposing the core material on the surface of the molded product while increasing the ratio of the core material, and colored to make it easier to determine when the core material is exposed on the surface. ) Was used as the core material.

Using a sandwich molding machine with a clamping force of 360 tons, a front cover (approximate dimensions: 400 × 150 mm, main part thickness: about 2.5 mm) of the desktop personal computer was molded.

The ratio between the core material and the surface material in the sandwich molded product is determined from the movement amount of the core material nozzle and the surface material nozzle, and the ratio of the recycled material contained in each of the core material and the surface material (preparation of material) Was described in each section of the Examples), the proportion of the recycled material contained in the molded article was calculated. As a result of examining the ratio of the core material that can be molded without exposing the core material to the surface by changing the molding conditions, it was 30%. [Example 1 Sandwich molding (2)] In the same manner as described in Reference example 1, material A033 described in [Preparation of material (4)] was used as a surface material, and [Preparation of material (1)].
A100 described above was used as the core material.

However, as for the color tone, a white material was used as described in [Material Preparation (1)] and [Material Preparation (4)]. Using a sandwich molding machine with a clamping force of 360 tons, a front cover (approximate dimensions of 400 × 150 mm, thickness of main part of about 2.5 mm) of the desktop personal computer body was molded.

The ratio of the core material to the surface material in the sandwich molded product is obtained from the movement amount of the core material nozzle and the surface material nozzle, and the ratio of the recycled material contained in each of the core material and the surface material ([[material Preparation]), the percentage of recycled material contained in the molded article was calculated.

A sandwich molded product having a core material ratio of 30% as in Reference Example 1 was obtained, and the stain on the surface was particularly problematic as compared with the case where normal injection molding was performed using an unused new material. There was no molded product. The ratio of the recycled material contained in the molded article was calculated from the ratio of the recycled material contained in each of the core material and the surface material (described in [Material Preparation (1)] and [Material Preparation (4)]). The content of the recycled material in the sandwich molded article is about 53% (in the surface layer: the content of the recycled material in the surface material is 33% × the ratio of the surface layer is 70%, that is, 23%).
%, In the core layer: the content of the recycled material in the core material was 100% × the ratio of the core layer was 30%, that is, 30%, that is, 53% in total).

In order to estimate the foreign matter in the sandwich molded article, 30% of the material has three foreign substances described in [Preparation of material (1)] and 30% of the foreign matter described in [Preparation of material (4)]. Is 70% of a single material, which is inferior to an unused new material, and is sufficiently clean, and has an Izod impact strength of 8.5 kgf.cm/cm@2 of a 30% material.
And 9.5 kgf · cm / cm 2 of 70% of the material, and can be sufficiently reused for the same product. Implementation but using materials described in the Comparative Example 1 sandwich molding (3) New materials unused] the surface material
Molding was performed in the same manner as in Example 1 to obtain a sandwich molded product. The content of the recycled material was 30%. [Comparative Example 2 Ordinary Injection Molding (1)] Using the material A033 described in [Preparation of Material (4)], an injection molding machine with a mold clamping force of 350 tons and the mold used in Example 1 were used. Used to form a front mask. The content of the recycled material in the molded article was 33% as estimated from the content of the recycled material in the material described in [Preparation of Material (4)]. [Reference Example 2 Sandwich molding (4)] Using material B009 (white) of [Preparation of material (5)] as a surface material, and using material B100 of [Preparation of material (2)] colored black as a core material used. Using a sandwich molding machine with a mold clamping force of 550 tons, a front cover (approximate dimensions: 400 × 150 mm, main part thickness: about 2.5 mm) of the desktop personal computer body was molded. The ratio between the core material and the surface material in the sandwich molded product is calculated from the movement amount of the core material nozzle and the surface material nozzle, and the ratio of the recycled material contained in each of the core material and the surface material ([preparation of material] (Described in each section), the ratio of recycled materials contained in the molded article was calculated.

The ratio of the core material that can be molded without exposing the core material to the surface was examined by changing the molding conditions. As a result, the ratio was 25%. [Example 2 Sandwich molding (5)] In the same manner as described in Reference example 2, material B009 of [Preparation of material (5)] was used as a surface material, and material B100 of [Preparation of material (2)] was used as a core material. Used as However, the color tone is [Material preparation (2)]
And a white material as described in [Preparation of Material (5)]. Using a sandwich molding machine with a mold clamping force of 550 tons, a front cover (approximate dimensions: 400 × 150 mm, main part thickness: about 2.5 mm) of the desktop personal computer body was molded.

The ratio between the core material and the surface material in the sandwich molded product is determined from the movement amount of the core material nozzle and the surface material nozzle, and the ratio of the recycled material contained in each of the core material and the surface material ([[material Preparation]), the percentage of recycled material contained in the molded article was calculated. As in Reference Example 2, a sandwich molded product having a core material ratio of 25% was obtained, and surface contamination was not particularly problematic as compared with a case where normal injection molding was performed using an unused new material. It was a product.

The ratio of the recycled material contained in each of the core material and the surface material ([Preparation of material (2)] and [Preparation of material (5)])
), The content of the recycled material in the sandwich molded product was about 32% (in the surface layer: 9% of the recycled material content in the surface material).
The ratio of the surface layer was 75%, ie, 7%, and in the core layer: the content of the recycled material in the core material was 100% × the ratio of the core layer was 25%, ie, 25%, for a total of 32%.

In order to estimate foreign matter in the sandwich molded product, the number of foreign matter described in [Preparation of material (2)] was 10
The material is 25%, and the number of foreign substances described in [Preparation of material (5)] is 75%. The material is inferior to the unused new material, but the Izod impact strength is 3%. 2.5 kgf.cm/cm2 material 25% and 9 kg
It is assumed that it is composed of 75% of the material of f · cm / cm 2 and can be sufficiently reused in the same product. [Comparative Example 3 Sandwich molding (6)] A sandwich molded product was obtained in the same manner as in Example 2 except that the material described in [Unused new material] was used as the surface material. The content of the recycled material was 25%. [Comparative Example 4 Normal Injection Molding (2)] Using the material B009 described in [Preparation of Material (5)], an injection molding machine with a clamping force of 350 tons and a mold used in Example 2 were used. Used to form a front mask. The content of the recycled material in the molded article was 9% as estimated from the content of the recycled material described in [Preparation of Material (5)]. [ Comparative Example 5 Sandwich molding (7)] In the same manner as in Example 2 except that the material C100 of [Preparation of material (3)] was used instead of the material B100 of [Preparation of material (2)] for the core material. This was performed to form a front mask. As in Example 2, a sandwich molded product having a core material ratio of 25% was obtained, and the surface was a molded product having no particular problem as compared with a case where ordinary new materials were used for injection molding. there were.

However, in order to estimate the foreign matter in the present sandwich molded product, 25% of the material having 100 foreign matters described in [Preparation of material (3)] was described in [Preparation of material (5)]. 75% of the material contains one foreign matter, and there is a problem in reusing the same foreign material. The ratio of the recycled material contained in the molded article was calculated from the ratio of the recycled material contained in each of the core material and the surface material (described in [Material Preparation (3)] and [Material Preparation (5)]). The content of the recycled material in the sandwich molded article is about 32% (in the surface layer: the content of the recycled material in the surface material is 9% × the ratio of the surface layer is 75%, ie, 7%; in the core layer: the recycled material in the core material) Content 100% x core layer ratio 2
5%, that is, 25%, and a total of 32%). Although there is a problem in using the same product again as a recycled material, the content of the recycled material is higher than those in Comparative Examples 3 and 4. A molded product with a clean surface was obtained.

[0041]

As described above, the molded article of the present invention provides (1) a molded article having a clean surface even when a recycled material is used.

(2) A larger amount of recycled material can be contained as compared with ordinary injection molded articles.

(3) By using the same type of resin (the type of resin, the type of flame retardant, etc.) for the core material and the surface material, it is possible to provide a product whose molded product can be recycled to the same product again.

(4) The above-mentioned effects can be obtained even for a molded product having a thickness of 3 mm or less.

(5) Therefore, the use of recycled materials for the housing of electric / electronic equipment is also effective.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of a sandwich molded product of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Core material 2 Surface material 4 Injection port 5 Mold

────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Hideaki Shimada 5-7-1 Shiba, Minato-ku, Tokyo NEC Corporation (72) Inventor Yoji Sato 5-7-1 Shiba, Minato-ku, Tokyo NEC (56) References JP-A 8-276538 (JP, A) JP-A 10-202694 (JP, A) JP-A 8-118418 (JP, A) JP-A 9-131759 (JP, A) A) JP-A-9-131760 (JP, A) JP-A-9-108084 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 B29C 45 / 00-45/84 B29C 49/00-49/80

Claims (3)

(57) [Claims] 1. A sandwich molded article comprising a core material and a surface material covering the entire surface of the core material, wherein both the surface material and the core material contain a recycled material, and the same type of material is different only in the content of the recycled material. Resin, and 5 to 50% by weight in the surface material;
When the recycled material is contained in the core material at a higher ratio than the surface material, and the total of the surface material and the core material is 100 parts by weight,
The ratio is 10 to 40 parts by weight, and the contamination in the core material is
With a radius of 100 μm per 0.1 square meter of surface area
The number of foreign substances having the above size is set to 10 or less, and the thickness of most of the molded article is 3 mm or less.
A sandwich molded product characterized by being capable of being sandwiched. 2. The percentage of recycled material contained in the surface material is 5%.
The sandwich molded article according to claim 1, wherein the weight percentage of the recycled material contained in the core material is 70% to 100% by weight. 3. When both the core material and the surface material are non-flame-retardant resins.
And if one is a flame retardant resin, only the type of resin is the same,
If both the core material and the surface material are flame retardant resins, the type of flame retardant
The sandwich molded article according to claim 1 or 2, which are the same .