WO2017020223A1

WO2017020223A1 - Composite material

Info

Publication number: WO2017020223A1
Application number: PCT/CN2015/085934
Authority: WO
Inventors: Wei-Feng Yen; Yong-yong XU; Chao-wen CHENG; Chienchih CHIU
Original assignee: Hewlett-Packard Development Company, L. P.
Priority date: 2015-08-03
Filing date: 2015-08-03
Publication date: 2017-02-09

Abstract

A composite material comprises a plastic layer, a first metal layer, and a second metal layer. The plastic layer comprises a polymeric material and has a first surface and a second surface opposite to the first surface. The first metal layer comprises a first metal material and is disposed on at least a portion of the first surface of the plastic layer. The second metal layer comprises a second metal material and is disposed on at least a portion of the second surface of the plastic layer.

Description

COMPOSITE MATERIAL

BACKGROUND

With development of electronic devices such as laptop computer and mobile phone, composite materials may be used as cover parts for a broad range of electronic devices.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present disclosure, reference should be made to the Detailed Description below, in conjunction with the following drawings in which like reference numerals refer to corresponding parts throughout the figures.

FIG. 1 is a schematic diagram illustrating the cross section of an example of a composite material with a sandwich structure having a plastic layer with both surfaces covered by metal layers.

FIGs. 2A and 2B are schematic diagrams illustrating the cross section of two examples of the composite material.

FIG. 3 is a flow diagram illustrating an example of the manufacturing method.

FIG. 4 is a flow diagram illustrating another example of the manufacturing method.

FIGs. 5A-5F are schematic views illustrating an example of the compression molding process.

FIG. 6 is a schematic view illustrating the cross section of an example of the housing.

FIGs. 7A and 7B are schematic views illustrating the cross section of two examples of the housing.

FIGs. 8A and 8B are schematic views showing the

cover parts

801, 802 and 803 of a laptop computer, wherein the composite material provided by an example of the present disclosure may be used for the top cover part 801, the bottom cover part 802 and the inner cover part 803 around the keyboard portion of the laptop computer.

DETAILED DESCRIPTION

Reference will now be made in detail to examples, which are illustrated in the accompanying drawings. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. Also, the figures are illustrations of an example, in which components or procedures shown in the figures are not necessarily essential for implementing the present disclosure. In other instances, well-known methods, procedures and components have not been described in detail so as not to unnecessarily obscure aspects of the examples.

Since users always expect the electronic devices to be portable, the cover parts are required to be light and thin. Meanwhile, the cover parts are also required to be strong enough to prevent warpage problem during manufacturing process and to protect the internal electronic circuits from the outside impact. Examples of the present disclosure provide a composite material, which may satisfy some of the above requirements.

FIG. 1 is a schematic diagram illustrating the cross section of an example of a composite material with a sandwich structure having a plastic layer with both surfaces covered by metal layers. Specifically, an example of the composite material may comprise a plastic layer 110 comprising a polymeric material and having a first surface and a second surface opposite to the first surface. A first metal layer 120 comprising a first metal material may be disposed on at least a portion of the first surface of the plastic layer. And a second metal layer 130 comprising a second metal material may be disposed on at least a portion of the second surface of the plastic layer. By coating the relatively light plastic layer with relatively stronger material on both surfaces of the plastic layer, the moment of inertia would be significantly improved with the same weight. In this way, a light composite material with high stiffness would be obtained. In an example, the composite material with both surfaces coated with metal layers exhibits a stiffness ratio 1.8 times of that of the material with metal layer formed on only one surface.

FIG. 2A and FIG. 2B are schematic diagrams illustrating the cross section of two examples of the composite material. As shown in FIG. 2A, in an example, the plastic layer 210 may comprise a polymeric material 211 as well as additives 212, and having a first surface and a second surface opposite to the first surface. A first metal layer 220 comprising a first metal material may be disposed on the first surface of the plastic layer 210, and a second metal layer 230 comprising a second metal material may be disposed on the second surface of the plastic layer 210. The shape of the additives 212 in FIG. 2A is for illustration purpose only, and does not have to be limited to globular shape. It may also have a rodlet shape, a sheet shape, or the like, as illustrated in FIG. 2B.

In another example, as shown in FIG. 2B, the composite material may comprise a plastic layer 210 comprising a polymeric material 211 as well as additives 212, and having a first surface and a second surface opposite to the first surface. A first bottom metal layer 221 comprising a first metal material and a second bottom metal layer 231 comprising a second metal material may be disposed on at least a portion of the first and second surfaces of the plastic layer 210, respectively. And a first top metal layer 222 comprising a third metal material and a second top metal layer 232 comprising a fourth metal material may be disposed on at least a portion of the outside surface of the first and

second bottom layers

221 and 231, respectively. In an example, the first metal material may be the same with the second material, and the third metal material may be the same with the fourth metal material. In another example, the first metal material may be the same with the fourth metal material, and the second metal material may be the same with the third metal material. The thickness of the bottom metal layers and the top metal layers may or may not be the same. In an example, the

bottom metal layers

221 and 231 may be made of Cu with a thickness of 0.01 mm, and the

top metal layers

222 and 232 may be made of Ni with a thickness of 0.04 mm.

In an example each of the first, second, third and fourth metal materials may be selected from the group comprising Ni, Cu, and Cr.

Table 1 shows the comparison between the composite material provided by an example of the present disclosure and conventional materials. The data is simulated by 2D plate type. For the metallic plastic composite material, the plastic layer with a thickness of 1.1 mm is made of ABS and mica, and each of the first and second metal layers consists of 0.01 mm of Cu layer and 0.04 mm of Ni layer. As a result, the total thickness of the composite material is 1.2 mm.

Table 1

From Table 1, it can be seen the example of the composite material of the present application has a weight comparable to that of a plastic material, exhibits a high stiffness comparable to that of the Al or Mg-Al alloy metal layer, meanwhile still maintains a small thickness. Further, the material for forming the metal layer of an example of the present disclosure is cheaper than materials already used such as Mg and Al, thus decreases the cost of the composite material.

In an example, the polymeric material forming the plastic layer may be selected from the group comprising acrylonitrile butadiene styrene (ABS) , polyurethane, polycyanurate, poly (methyl methacrylate) (PMMA) , polycarbonate (PC) , poly (p-phenylene sulfide) (PPS) , and a mixture thereof.

In an example, the polymeric material forming the plastic layer may be acrylonitrile butadiene styrene (ABS) .

In an example, the plastic layer may further comprise additives. The additives may be selected from the group comprising mica, talc, glass fiber, carbon fiber and a mixture thereof. The additives may be presented small particles. In an example, the particles may have a rodlet shape, a sheet shape, a globular shape, or the like. In an example, the additive may be mica.

In an example, the plastic layer comprises 70 to 95 parts by weight of the polymeric material and 5 to 30 parts by weight of additives, based on 100 parts by weight of the total amount of the plastic layer. In this range, the plastic layer may contribute to lighter density and maintain strong stiffness, thus may prevent warpage issue even with a thin thickness.

The following Table 2 shows the property of different examples of the composite materials. Specifically, the plastic layer of the composite materials comprising ABS resin and the additives listed in Table 2 is formed first. Then a first and a second metal layers are formed on both sides of the plastic layer to cover at least a portion of the surface. As to be seen, comparing with the composite material in which the plastic layer does not comprise any additive, the composite materials with additives exhibit less deformation level, representing a high stiffness ratio.

Table 2

Additive	Form	Percent	Deformation
Additive	Form	Percent	Deformation	Mica	Rodlet/sheet	5％-30％	＜1.5 mm
glass fiber	Rodlet/globular	5％-30％	＜1.5 mm	Mica	Rodlet/sheet	5％-30％	＜1.5 mm
glass fiber	Rodlet/globular	5％-30％	＜1.5 mm	carbon fiber	Rodlet/globular	5％-30％	＜1.5 mm
without additive	/	/	＞2 mm	carbon fiber	Rodlet/globular	5％-30％	＜1.5 mm

In an example, the plastic layer has a thickness of 0.7 to 1.4 mm. If the thickness is below 0.7 mm, the final composite material may not have a sufficient stiffness and therefore may suffer from warpage problem. If the thickness is above 1.4 mm, the weight of the final composite material may be too heavy.

In an example, each of the first metal layer and the second metal layer and has a thickness of 0.05 to 0.15 mm. If the thickness is less than 0.05 mm, the final composite material may not have a sufficient stiffness and therefore may suffer from warpage problem. If the thickness is above 0.15 mm, the weight of the final composite material may be too heavy.

An example of the present disclosure provides a method of manufacturing a composite material. FIG. 3 is a flow diagram illustrating an example of the manufacturing method. Specifically, as shown in block 301, a plastic layer comprising a polymeric material and having a first surface and a second surface opposite to the first surface may be formed first. And then a first metal layer and a second metal layer may be formed on the first and second surface of the plastic layer (block 302) , wherein the first metal layer comprises a first metal material, and the second metal layer comprises a second metal material. In an example, the first and second metal layers may be formed sequentially. In another example, the first and second metal layers may be formed simultaneously.

FIG. 4 is a flow diagram illustrating another example of the manufacturing method. Specifically, as shown in block 401, a plastic layer comprising a polymeric material and having a first surface and a second surface opposite to the first surface may be formed first. A first bottom metal layer comprising a first metal material may be formed on the first surface of the plastic layer, and a second bottom metal layer comprising a second metal material may be formed on the second surface of the plastic layer (block 402) . A first top metal layer comprising a third metal material may be formed on the outside surface of the first bottom metal layer, and a second top metal layer comprising a fourth metal material may be formed on the outside surfaces of the second bottom metal layer (block 403) . In this way, the adhesion of the metal layers to the plastic layer may be improved, and a lighter composite material with high stiffness may be obtained. The plastic layer may be formed by mixing the polymeric material with the additives, and then molded through a compression molding process, an injection molding process, or a spin casting process.

In an example, the plastic layer is molded through compression molding process. It is a closed mold process, produces high strength, complex parts in a wide variety of sizes. FIGs. 5A to 5F illustrate an example of the compression molding process. Specifically, first, the heated polymeric material 501 is injected into a mold cavity 502 with a spacing distance of 2 to 3 mm (FIG. 5A-5B) . The temperature is sufficient to maintain a suitable low viscosity of the polymeric material. In an example, the temperature is in the range of 175 to 380℃. Appropriate temperature is chosen according to the polymeric material used for forming the plastic layer. For example, for ABS and PMMA resin, the temperature may be in the range of 180 to 240℃； for PC, the temperature may be in the range of 220 to 280℃； for PPS resin, the temperature may be in the range of 290 to 360℃； for PA resin, the temperature may be in the range of 220 to 380℃； for polyurethane resin, the temperature may be in the range of 175 to 230℃. Second, as illustrated in FIG. 5C, the mold is closed to decrease the spacing distance of the mold cavity 502 into a range of 0.7 to 1.4 mm and the polymeric material 501 is forced to fill up the entire cavity. Then the temperature is decreased to be low enough for the melted polymeric material 501 to cure. After the upper part of the mold 503 is released (FIG. 5D-5E) , an ejector pin 505 in the bottom of the mold ejects the finished piece 504 out of the mold and a plastic layer with a first surface and a second surface opposite to the first surface is obtained (FIG. 5F) . In this way, the polymeric material and additives distribute more evenly, the internal stress is reduced effectively, and the obtained plastic layer has high strength, thus effectively prevents the warpage issue. Further, the formed plastic layer has a thin thickness of 0.7 to 1.4 mm, therefore decreases the weight thereof.

Next, the first and second metal layers are formed on the first and second surfaces of the plastic layer through electroplating process or sputtering process. Fixture control electric current may be applied to obtain uniform thickness. In an example, the thickness of the first and second metal layers is controlled to be 0.05 to 0.15 mm. The thickness of the first and second metal layers may or may not be the same. As a result, a high stiffness composite material may be obtained.

In an example, Cu metal layers may be formed as bottom metal layers on both the first and second surfaces of the plastic layer, and Ni metal layers may be formed as top metal layers on the outside surfaces of both Cu metal layers. In an example, the thickness of the Ni metal layers may be larger than that of the Cu metal layers. In another example, the Ni metal layers may have a thickness of 0.04 mm, and the Cu metal layers may have a thickness of 0.01 mm.

In an example, the composite material may be further subjected to nano-painting or other cosmetic process to obtain a color metallic feeling.

An example of the present disclosure also provided a housing of an electronic device using the composite material of an example of the present disclosure. FIG. 6 illustrates an example of the housing, which may comprise a core layer 610 comprising a polymeric material and having a first surface and a second surface opposite to the first surface. A first layer 620 comprising a first metal material may be disposed on at least a portion of the first surface of the core layer 610. And a second layer 630 comprising a second metal material may be disposed on at least a portion of the second surface of the core layer 610. Said polymeric material, additives and the definition of the first and second metal materials may be the same with the above mentioned materials. In an example, the electronic device may be selected from the group comprising a notebook computer, a mobile phone, a tablet computer and a desktop computer.

FIGs. 7A and 7B further illustrate two example of the housing. In an example, as illustrated in FIG. 7B, the composite material may comprise a core layer 710 comprising a polymeric material 711 and additives 712, and having a first surface and a second surface opposite to the first surface. A first layer 720 comprising a first metal material may be disposed on at least a portion of the first surface of the core layer 710. And a second layer 730 comprising a second metal material may be disposed on at least a portion of the second surface of the core layer 710. In another example, as illustrated in FIG. 7B, the composite material may comprise a core layer 710 comprising a polymeric material 711 and additives 712, and having a first surface and a second surface opposite to the first surface. A first bottom layer 721 comprising a first metal material and a second bottom layer 731 comprising a second metal material may be disposed on at least a portion of the first and second surfaces of the core layer 710, respectively. And a first top layer 722 comprising a third metal material and a second top layer 732 comprising a fourth metal material may be disposed on at least a portion of the outside surfaces of the first and second

bottom layer

721 and 731, respectively. The shape of the additives 712 in FIG. 7A is for illustration purpose only, and does not have to be limited to globular shape. It may also have a rodlet shape, a sheet shape, or the like, as illustrated in FIG. 7B. The thickness of the bottom layer and the top layer may or may not be the same. In an example, the bottom layers 721 and 731 may be made of Cu with a thickness of 0.01 mm, and the

top layers

722 and 732 may be made of Ni with a thickness of 0.04 mm.

In an example, the housing of an electronic device may be used for the top cover part 801, the bottom cover part 802 and the inner cover part 803 around the keyboard portion of a notebook computer, as illustrated in FIGs. 8A and 8B.

The foregoing description, for the purposes of explanation, has been described with the reference to specific examples. However, the illustrative discussions above are not intended to be exhaustive or to limit the present disclosure to the precise forms disclosed. Many modifications and variations are possible in view of the above teachings. The examples were chosen and described in order to best explain the principles of the present disclosure and its practical applications, to thereby enable others skilled in the art to best utilize the present disclosure and various examples with various modifications which are suited to the particular use contemplated.

Claims

A composite material, comprising:

a plastic layer comprising a polymeric material and having a first surface and a second surface opposite to the first surface；

a first metal layer comprising a first metal material and disposed on at least a portion of the first surface of the plastic layer； and

a second metal layer comprising a second metal material and disposed on at least a portion of the second surface of the plastic layer.
The composite material according to claim 1, wherein the polymeric material is selected from the group comprising acrylonitrile butadiene styrene (ABS) , polyurethane, polycyanurate, poly (methyl methacrylate) (PMMA) , polycarbonate (PC) , and poly (p-phenylene sulfide) (PPS) .
The composite material according to claim 1, wherein the plastic layer comprises 70 to 95 parts by weight of the polymeric material based on 100 parts by weight of the plastic layer.
The composite material according to claim 1, wherein the plastic layer comprises 70 to 95 parts by weight of the polymeric material based on 100 parts by weight of the plastic layer.
The composite material according to claim 4, wherein the additives are selected from the group comprising mica, talc, glass fiber, carbon fiber, and a combination thereof.
The composite material according to claim 1, wherein the plastic layer has a thickness of 0.7 to 1.4 mm.
The composite material according to claim 1, wherein each of the first metal material and the second metal material is selected from the group comprising Ni, Cu, and Cr.
The composite material according to claim 1, wherein each of the first metal layer and the second metal layer comprises:

a bottom metal layer, attached to each of the first and second surfaces of the plastic layer； and

a top metal layer, attached to an outside surface of the bottom metal layer.
The composite material according to claim 1, wherein each of the first metal layer and the second metal layer has a thickness of 0.05 to 0.15 mm.
A method of manufacturing a composite material, comprising:

forming a plastic layer comprising a polymeric material and having a first surface and a second surface opposite to the first surface；

forming a first metal layer and a second metal layer on the first and second surface of the plastic layer respectively, wherein the first metal layer comprises a first metal material, and the second metal layer comprises a second metal material.
The method according to claim 10, wherein the plastic layer is formed by a compression molding process, an injection molding process, or a spin casting process.
The method according to claim 10, wherein each of the first metal layer and the second metal layer is formed by a process selected from the group comprising an electroplating process, and a sputtering process.
The method according to claim 10, wherein forming the first metal layer and the second metal layer on the first and second surface of the plastic layer respectively comprises:

forming a bottom metal layer on each of the first and second surfaces of the plastic layer； and

forming a top metal layer on an outside surface of the bottom metal layer.
A housing of an electronic device, comprising a composite material comprising:

a core layer comprising a polymeric material and having a first surface and a second surface opposite to the first surface；

a first layer comprising a first metal material and disposed on at least a portion of the first surface of the core layer； and

a second layer comprising a second metal material and disposed on at least a portion of the second surface of the core layer.
The housing according to claim 14, wherein the electronic device is selected from the group comprising a notebook computer, a mobile phone, a tablet computer, or a desktop computer.