WO2016026398A1

WO2016026398A1 - Liquid silicone rubber injection molding method and electronic device with display screen

Info

Publication number: WO2016026398A1
Application number: PCT/CN2015/086612
Authority: WO
Inventors: 杜永杰; 樊建军; 陈志远
Original assignee: 阿里巴巴集团控股有限公司; 杜永杰; 樊建军; 陈志远
Priority date: 2014-08-21
Filing date: 2015-08-11
Publication date: 2016-02-25
Also published as: HK1221939A1; CN105437449B; CN105437449A

Abstract

Provided in the present invention are a liquid silicone rubber injection molding method and an electronic device with a display screen. The method comprises: coating the product to be injected with Overmolding glue, injecting a liquid silicone rubber at a low temperature on the product after the glue solidified, the low temperature is from 25℃ to 80℃. The electronic device with a display screen comprises a device housing and a display module, the display module comprises a glass cover plate and a display screen and is molded by injecting the liquid silicone rubber at a low temperature, wherein the display screen is bonded with the glass cover plate, the width of the glass cover plate is less than that of the display screen, and the edge of the display screen is fixed to the device housing. In the present invention, the width of the glass cover plate is less than that of the display screen, and the edge of the display screen is fixed by the device housing, therefore blocked areas are no longer required to be printed on the two sides of the glass cover plate. Injecting the liquid silicone rubber at a low temperature on the electronic device ensures that the electronic device will not be burned out and the binding force between the silicone rubber and the electronic device at a low temperature environment.

Description

Liquid silicone injection molding method and electronic device with display

Technical field

The present invention relates to the field of terminal technologies, and in particular, to a liquid silicone injection molding method and an electronic device with a display screen.

Background technique

At present, in the manufacture of terminal equipment, there has been an attempt to integrally injection molding of silica gel and glass. However, since the temperature of silicone injection molding is usually 180 ° C, it cannot be used on products that are afraid of high temperature; in addition, the curing speed of silica gel is slow (conventional in about 10 minutes), affecting productivity, and it is particularly easy to fall off, resulting in poor assembly and appearance. Hey questions.

Summary of the invention

The embodiment of the invention provides a liquid silicone injection molding method and an electronic device with a display screen, which solves the problem that the prior art silicone injection molding cannot be used for fear of high temperature products.

The embodiment of the invention provides a liquid silicone injection molding method, comprising the following steps:

Applying overmolding glue to the product to be injection molded;

After the glue is solidified and molded, the product to be injection molded is subjected to low temperature liquid silicone injection molding, and the low temperature is 25 ° C to 80 ° C.

The benefits are as follows:

According to the technical solution provided by the embodiments of the present invention, the injection molding of the low temperature liquid silicone rubber for the injection molded product can realize the injection molding of the silicone rubber for the product which is afraid of high temperature. In the low temperature environment, it not only does not burn out the products to be injection, but also ensures the adhesion between the silica gel and the parts to be injection molded, ensuring product quality and performance.

Embodiments of the present invention provide a display with a liquid crystal injection molding method. The electronic device comprises a device casing and a display module, and the display module comprises a glass cover plate and a display screen, and the display module is injection molded by the liquid silicone injection molding method, wherein:

The display screen is bonded to the glass cover plate, and the width of the glass cover plate is smaller than the width of the display screen;

The edge of the display is attached to the device housing.

The benefits are as follows:

The technical solution provided by the embodiment of the invention makes the width of the glass cover smaller than the width of the display screen, and fixes the edge of the display screen through the device casing, and discards the prior art to fix the display through the glass cover plate. In this way, it is no longer necessary to print the occlusion area on both sides of the glass cover, so that the distance from the display area of the device to the outer edges of both sides of the device is narrowed.

DRAWINGS

Specific embodiments of the present invention will be described below with reference to the accompanying drawings, in which:

1 is a schematic flow chart showing the implementation of a liquid silicone injection molding method in an embodiment of the present invention;

2 is a schematic view showing the implementation of injection molding of liquid silicone in the embodiment of the present invention;

3 is another schematic view showing the implementation of injection molding of liquid silicone in the embodiment of the present invention;

4 is another schematic view showing the implementation of liquid silicone injection molding in the embodiment of the present invention;

FIG. 5 is a schematic structural view showing a cross section of an electronic device with a display screen according to an embodiment of the present invention; FIG.

6 is a schematic enlarged structural view showing a cross section of an electronic device in an embodiment of the present invention;

FIG. 7 is a schematic diagram showing an implementation of an electronic device in an embodiment of the present invention; FIG.

FIG. 8 is another schematic diagram showing an implementation of an electronic device in an embodiment of the present invention;

FIG. 9 is another schematic diagram showing an implementation of an electronic device in an embodiment of the present invention;

FIG. 10 is a schematic diagram showing the completion of the electronic device in the embodiment of the present invention.

detailed description

The exemplary embodiments of the present invention are further described in detail below with reference to the accompanying drawings, Some embodiments, rather than all of the embodiments, are exhaustive. And in the case of no conflict, the features in the embodiments and the embodiments in the description can be combined with each other.

The inventor noticed during the invention:

Taking the liquid crystal display module (LCM) as an example, the conventional LCM can withstand temperature and ensure product quality, the normal temperature is 80 degrees Celsius; and the touch screen (TP, Touch Panel) is also because of the inside. There are lines that cannot withstand too high temperatures. However, the silicone injection molding temperature currently used is generally 180 °C. Therefore, there is an urgent need for a lower temperature silicone injection molding method.

In view of the above deficiencies, the embodiment of the present invention proposes a liquid silicone injection molding method, which will be described below.

1 is a schematic flow chart showing the implementation of a liquid silicone injection molding method in an embodiment of the present invention. As shown in the figure, the following steps may be included:

Step 101, applying Overmolding glue to the product to be injection molded;

Step 102: After the glue is solidified and molded, the injection molded product is subjected to low temperature liquid silicone injection molding, and the low temperature is 25 ° C to 80 ° C.

Liquid Silicone Rubber (LSR) is a non-toxic, heat-resistant, highly resilient, flexible thermoset material. The liquid silicone injection molding process is generally: the operation of the LSR feeder combines the A component and the B component in a precise 1:1 ratio, and because some of the products are colored, it can be equipped with a color pump set and a color metering part. The A+B components, additives, colors, etc. are thoroughly mixed and then enter the plasticizing system. The plasticating screw has the functions of homogenization and mixing, and the mixture is injected into the hot mold through the screw. In the embodiment of the invention, the curing reaction of the silica gel occurs at a mold temperature of 25 ° C to 80 ° C. A horizontal liquid silicone molding system or a vertical liquid silicone molding unit can be used, which is not limited in the present invention.

For products with lines or glass, such as mobile terminals with glass cover, taking the touch screen as an example, when the fully-fitted LCM module is glued into a composite mold by the normal temperature silicone molding method, it has the following disadvantages:

1) Without elasticity, losing the characteristics of the protective glass product and the screen;

2) The curing time is too long, about 12 to 24 hours, and the normal production line is not allowed;

3) The molding precision is not enough, and the appearance has an influence on the appearance, and the purpose of protecting the screen cannot be achieved at the same time.

Therefore, the embodiment of the present invention can also be implemented by the following method.

In practice, the low temperature may be from 70 ° C to 80 ° C.

In the implementation, the thickness of the silica gel after the low temperature liquid silicone injection molding may be 0.3 mm to 0.4 mm.

In order to make the silica gel better combined with the product to be injection molded, the embodiment of the present invention can also be implemented by the following method.

In practice, the glue may be an active glue that is active at 70 ° C to 80 ° C.

In the embodiment of the present invention, by using the active glue, when the product to be injection molded is made of glass, the glass cross section can be activated to improve the bonding performance.

In practice, the glue can be cured by ultraviolet (UV, Ultraviolet Rays) light irradiation on the glued product to be injection molded.

Since the active glue is coated on the product to be injection molded, when the temperature reaches 70° C. to 80° C., the activity of the active glue is excited, the adhesion between the product to be injection and the silica gel is ensured, and the quality of the product to be injection molded is ensured. performance.

In the implementation, the products to be injection-molded can be line glass products, products with display screens, plastic products with lines, etc. Among them, plastic products with lines can be further transparent plastic products.

In the implementation, since the above products are relatively common and mainstream, and are easily understood by those skilled in the art, only the above products are taken as an example here; however, the products to be injection molded provided by the embodiments of the present invention may also be other types of products. For example, polyethylene terephthalate (PET) products and the like, the above products are only used to teach those skilled in the art how to implement the invention, but are not meant to be limited to the above products.

In practice, the product to be injection molded may include a display module bonded by a display screen and a glass cover.

In the implementation, the low-temperature liquid silicone injection molding of the injection molded product may be performed by low-temperature liquid silicone injection molding of the display module of the injection molding product by the mold.

In the implementation, the low-temperature liquid silicone injection molding of the injection molded product may be performed by performing a low-temperature liquid silicone injection molding on the display module of the injection molded product and the equipment casing of the product to be injection molded.

Generally, various molds and tools used in industrial production for injection molding, blow molding, extrusion, die casting or forging, smelting, stamping, etc. to obtain desired products are called molds. In short, a mold is a tool for forming an article, and the tool is composed of various parts, and different molds are composed of different parts.

In the implementation, the precision of the low temperature liquid silicone injection molding may be 0.1 mm or less.

The low-temperature liquid silicone gel of the embodiment of the invention is formed by low-temperature molding, and the thickness is 0.3-0.4 mm. After the molding is completed, the fitting tolerance of the screen and the glass cover plate is absorbed, and the surface is evenly gaped after the assembly is completed, which meets the normal production requirements. . Therefore, the technical solution provided by the embodiment of the present invention can be used for a terminal device having a narrow bezel, no border, or waterproof, etc., and the waterproof precision of the screen protection can be improved, thereby realizing the problem of the fall protection in a small range.

The process of liquid silicone injection molding is described below by taking a mobile phone including a display module bonded by a display screen and a glass cover as an example.

1) Apply 70 ° C active glue to the outer edge of the display module, as shown in Figure 2;

2) After 7 seconds of UV light irradiation, the glue is solidified, and then can be placed for 7 days (or 168 hours), and the molding performance can be activated within 7 days (or 168 hours), as shown in Figure 3. Show

3) Silicone injection molding is carried out under the environment of 70-80 ° C to ensure product quality and performance, as shown in Figure 4.

After the mold is injected, the circuit of the screen and the touch screen is not affected by the temperature, and the elastic property of the 30-degree hardness silica gel is ensured. Because of the activeness of the glue, the bonding force between the silicone and the screen is strong enough to not fall off. .

The embodiment of the invention provides a combination of a low temperature (70° C.-80° C.) silica gel and a glass circuit board with a line, a silica gel and a glass electronic component such as a screen. The technical solution of the invention can be formed at 80° C. Applied to products with lines and displays, the curing speed is only 5 minutes, and the production capacity is doubled. Because the active glue is applied to the edge of the display and the glass cover, the temperature reaches 70 ° C. When it is around ~80 °C, it will stimulate its activity and ensure the adhesion between glass products and silica gel. It not only ensures that the screen and TP traces are not burnt, but also ensures the adhesion between the silicone and the glass cover and TP to ensure product quality and performance.

Based on the same inventive concept, an embodiment of the present invention provides an electronic device with a display screen produced by the above liquid silicone injection molding method, which will be described below.

FIG. 5 is a schematic structural view showing a cross section of an electronic device with a display screen according to an embodiment of the present invention, and FIG. 6 is an enlarged schematic view showing the cross section. As shown, the device housing 1 and the display module may be included. The display module comprises a glass cover (also called a glass panel) 201 and a display screen 202, and the display module is injection molded by using the above low temperature liquid silicone, wherein:

The display screen 202 is bonded to the glass cover 201, and the width of the glass cover 201 is smaller than the width of the display screen 202;

The edge of the display screen 202 is fixed to the device housing 1.

In the implementation, the display fixing bracket (also referred to as a backboard fixing bracket) 3 attached to the display screen may be further included, and the display module is fixed on the display fixing bracket 3.

The display fixing bracket referred to in the embodiment of the present invention may be a stainless steel plate having a thickness of 0.5 mm or the like.

In the implementation, the stainless steel plate or the like is adopted because the method is relatively common and mainstream, and is easy to be used/understood by those skilled in the art, so the stainless steel plate is taken as an example here; however, it is theoretically possible to adopt other methods as long as it can be realized. The purpose of fixing the display screen is only. The stainless steel plate is only used to teach the person skilled in the art how to implement the invention, but it does not mean that only the stainless steel plate can be used. In the implementation process, the corresponding materials and thicknesses can be determined according to practical needs. .

In the implementation, the display screen can be a light emitting diode (LED) display, a liquid crystal display (LCD), or an organic light-emitting diode (OLED).

Taking the LCM display as an example, the embodiment of the present invention makes the glass cover smaller than the LCD display module (LCM, LCD Module), so that the edge of the display screen is fixed by the device housing. The display is not fixed by conventional glass cover. In the prior art, the glass cover is used to fix the display screen, the display screen has a tolerance of at least 1 mm on one side of the glass cover, and the glass cover to the device housing has a tolerance of 1.2 mm. Therefore, in the manner provided by the embodiment of the present invention, the width of 2.2 mm can be omitted on one side, and the width of the device can be omitted as a whole, and the cover is not required to be printed on both sides of the glass cover (black). Or white area, which narrows the display area of the device to the outer edges of the two sides of the device. Thereby, the screen display area of the electronic device can be made larger, or the electronic device of the larger screen can be made narrower and the grip feeling is better.

The embodiment of the present invention adopts a frameless technology, and the frame referred to herein refers to a occlusion area printed on both sides of the glass cover in the prior art. In the embodiment of the present invention, the glass cover area is all a display area. Viewed from the front of the device, there are no borders on the left and right sides or the border is very narrow. In the embodiment of the present invention, the line of the display screen can be blocked by the silicone, or the line of the display screen can be taken out from above or below the device (from the front) without the frame to block the left and right sides of the electronic device, thereby achieving no border or The purpose of the narrow border.

Since the electronic device provided by the embodiment of the invention adopts the liquid silicone injection molding method described above, the display screen is protected by the low-temperature liquid silicone molding technology to achieve the purpose of anti-drop, anti-static and waterproof. The low temperature liquid silicone used in the embodiment of the invention is formed by low temperature molding and the thickness of the produced silica gel is 0.3 mm to 0.4 mm (that is, 0.3 mm or more and 0.4 mm or less), and the screen and the glass cover are just absorbed after the molding is completed. The fitting tolerance of the board can be guaranteed within 0.1mm. It guarantees a uniform gap after assembly and meets normal production requirements.

In implementation, the electronic device can be a device such as a mobile phone, a tablet computer or an electronic watch.

Taking the mobile phone as an example, the embodiment of the invention can realize the combination of the glass cover plate of the mobile phone, the display screen or the fully-fitted glass cover plate and the display screen, and the silica gel. Thereby, the glass cover plate and the display circuit line are formed in an acceptable temperature range, and the assembly tolerances of the display screen and the glass cover plate are absorbed, the assembly gap is minimized, and the protection screen seismic test is realized within 0.4 mm.

The embodiment of the invention provides two methods for preparing liquid silicone injection molding of an electronic device:

First, the glass cover 201 and the display screen 202 as a whole (ie, the display module) utilize liquid silicon Glue injection molding, liquid silicone injection molding around the display module;

For the glass cover 201 and the display screen 202, ordinary silica gel or the like can be used, or the glass cover 201 is usually adhered to when the display screen 202 is provided by the manufacturer, and the present invention does not limit this.

Second, the embodiment of the present invention can also fix the glass cover 201 and the display screen 202 (ie, the display module) and the device casing 1 by liquid silicone molding technology.

Of course, in the implementation, the above two methods can also be combined, that is, after the glass cover 201 and the display screen 202 are integrally formed of liquid silicone, the display module and the device housing 1 are further processed. Sub-liquid silicone molding.

In the following, the liquid crystal forming of the display module is taken as an example, and the production and implementation instructions are performed.

1) liquid crystal forming of the display module with the glass cover 201 bonded to the display screen 202 by the jig and the mold, as shown in FIG. 7;

2) loading the formed display module from the back of the device housing 1, as shown in FIG. 8, flattening and mounting;

3) loading the display fixing bracket 3 from the back of the device housing 1, as shown in FIG. 9, compacting and fixing the display module;

4) After the production is completed, the effect diagram seen from the front of the device is shown in Fig. 10.

While the preferred embodiment of the invention has been described, it will be understood that Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and the modifications and

Claims

A liquid silicone injection molding method, comprising the following steps:

Applying the mold to be injection molded to mold overmolding glue;

After the glue is solidified and molded, the product to be injection molded is subjected to low temperature liquid silicone injection, and the low temperature is 25 ° C to 80 ° C.
The method of claim 1 wherein said low temperature is between 70 ° C and 80 ° C.
The method according to claim 1 or 2, wherein the silica gel has a thickness of from 0.3 mm to 0.4 mm.
The method according to claim 1 or 2, wherein the glue is an active glue which is active at 70 ° C to 80 ° C.
The method according to claim 4, wherein the solidification molding of the product to be injection molded is cured by irradiating the glue with ultraviolet light.
The method according to claim 1, 2 or 5, characterized in that the product to be injection molded is a product with a line glass, a product with a display or a plastic with a line.
The method according to claim 1, 2 or 5, wherein the product to be injection molded comprises a display module bonded by a display screen and a glass cover.
The method according to claim 7, wherein the low-temperature liquid silicone injection molding is performed on the product to be injection-molded, in particular, the display module of the product to be injection-molded is subjected to low-temperature liquid silicone injection molding.
The method according to claim 7, wherein the low-temperature liquid silicone injection molding of the product to be injection-molded is performed by performing a low-temperature liquid state on the display module of the product to be injection-molded and the device housing of the product to be injection-molded. Silicone injection molding.
An electronic device with a display screen produced by the method according to any one of claims 1 to 9, comprising a device housing and a display module, wherein the display module comprises a glass cover and a display screen. The display module is injection molded by the method according to any one of claims 1 to 9, wherein:

The display screen is bonded to the glass cover plate, and the width of the glass cover plate is smaller than the width of the display screen;

The edge of the display screen is secured to the device housing.
The electronic device according to claim 10, further comprising: a display fixing bracket attached to the display screen, wherein the display module is fixed on the display fixing bracket.