CN105437449B - A kind of liquid-state silicon gel injection moulding process and the electronic equipment with display screen - Google Patents

Abstract

The invention provides a liquid silicone injection molding method and an electronic device with a display screen, comprising: coating the product to be injected with mold injection overmolding glue; after the glue is cured and formed, the product to be injected is subjected to low-temperature liquid silicone injection molding, and the low temperature is 25 ° C ~ 80°C. Electronic equipment with a display screen, including a device housing and a display module, the display module includes a glass cover and a display screen, the display module is formed by injection molding of low-temperature liquid silicone, wherein: the display screen is bonded to the glass cover , the width of the glass cover is smaller than the width of the display screen; the edge of the display screen is fixed to the device casing. In the present invention, the width of the glass cover is made smaller than the width of the display screen, and the edge of the display screen is fixed through the device casing, and it is no longer necessary to print the shielding area on both sides of the glass cover; Injection molding can not only ensure that the electronic equipment will not be burned out in a low temperature environment, but also ensure the adhesion between the silica gel and the components of the electronic equipment.

Description

A liquid silicone injection molding method and electronic equipment with a display

technical field

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

Background technique

At present, in the manufacturing process of terminal equipment, there have been attempts to integrally inject silica gel and glass. However, since the current injection molding temperature of silicone is usually 180°C, it cannot be used for products that are afraid of high temperatures; in addition, the curing speed of silicone is relatively slow (usually about 10 minutes), which affects productivity, and is particularly easy to fall off, resulting in poor assembly and appearance defects etc.

Contents of the invention

The embodiment of the present invention proposes a liquid silicone injection molding method and an electronic device with a display screen, which solves the problem in the prior art that silicone injection molding cannot be used for products that are afraid of high temperatures.

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

Coat the product to be injected with Overmolding glue;

After the glue is cured and formed, the product to be injected is subjected to low-temperature liquid silicone injection molding, and the low temperature is 25°C to 80°C.

Beneficial effects are as follows:

In the technical solution provided by the embodiment of the present invention, by performing low-temperature liquid silicone injection on the product to be injected, silicone injection molding on products that are afraid of high temperatures can be realized. In a low temperature environment, it not only ensures that the product to be injected will not be burned out, but also ensures the adhesion between the silicone and the parts of the product to be injected, ensuring product quality and performance.

An embodiment of the present invention provides an electronic device with a display screen manufactured by the above-mentioned liquid silicone injection molding method, including a device housing and a display module, the display module includes a glass cover plate and a display screen, and the display module uses the above-mentioned liquid silicone Silicone injection molding method injection molding, of which:

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

The edge of the display screen is fixed to the device casing.

Beneficial effects are as follows:

In the technical solution provided by the embodiment of the present invention, the width of the glass cover is made smaller than the width of the display screen, and the edge of the display screen is fixed through the device casing, which eliminates the need to fix the display screen through the glass cover plate in the prior art In this way, it is no longer necessary to print shielding areas on both sides of the glass cover, so that the distance from the display area of the device to the outer edges of the two sides of the device is narrowed.

Description of drawings

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

Fig. 1 shows the schematic flow sheet of the implementation of liquid silicone injection molding method in the embodiment of the present invention;

Figure 2 shows a schematic diagram of the implementation of liquid silicone injection molding in the embodiment of the present invention;

Fig. 3 shows another schematic diagram of the production and implementation of liquid silicone injection molding in the embodiment of the present invention;

Fig. 4 shows another schematic diagram of the production and implementation of liquid silicone injection molding in the embodiment of the present invention;

FIG. 5 shows a schematic structural diagram of a cross-section of an electronic device with a display screen in an embodiment of the present invention;

FIG. 6 shows a schematic diagram of an enlarged structure of a cross-section of an electronic device in an embodiment of the present invention;

Figure 7 shows a schematic diagram of the implementation of electronic equipment in the embodiment of the present invention;

Fig. 8 shows another schematic diagram of the manufacture and implementation of electronic equipment in the embodiment of the present invention;

Fig. 9 shows another schematic diagram of the manufacture and implementation of electronic equipment in the embodiment of the present invention;

Fig. 10 shows a schematic diagram of the completion of the electronic device in the embodiment of the present invention.

Detailed ways

In order to make the technical solutions and advantages of the present invention clearer, the exemplary embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all implementations. Exhaustive list of examples. And in the case of no conflict, the embodiments in this description and the features in the embodiments can be combined with each other.

The inventor noticed during the invention that:

Taking the LCD display module (LCM, Liquid Crystal Display Module) as an example, when the existing LCM can withstand the temperature and ensure the product quality, the conventional temperature is 80 degrees Celsius; and the touch screen (TP, Touch Panel) is currently also due to the internal There are lines that cannot withstand too high a temperature. But 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 shortcomings, an embodiment of the present invention proposes a liquid silicone injection molding method, which will be described below.

Fig. 1 shows a schematic flow diagram of the implementation of the liquid silicone injection molding method in the embodiment of the present invention, as shown in the figure, may include the following steps:

Step 101, coating the product to be injected with Overmolding glue;

Step 102 , after the glue is cured and molded, perform low-temperature liquid silicone injection molding on the product to be injection-molded, and the low-temperature temperature is 25° C. to 80° C.

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

For products with lines or glass, such as mobile terminals with glass covers, etc., taking touch screens as an example, when fully bonded LCM modules are glued and molded by room temperature silicone molding, there are the following disadvantages:

1) No elasticity, lose the characteristics of protective glass products and screens;

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

3) Molding accuracy is not enough, the appearance will be affected after assembly, and the purpose of protecting the screen cannot be achieved at the same time.

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

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

In practice, the thickness of the silica gel after low-temperature liquid silica gel injection molding can be 0.3 mm to 0.4 mm.

In the embodiment of the present invention, in order to better combine the silica gel with the product to be injected, the following methods can also be used for implementation.

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 injected is made of glass, the cross section of the glass can be activated to improve the bonding performance.

During implementation, the glue can be cured by irradiating ultraviolet (UV, Ultraviolet Rays) light on the product to be injected that has been coated with glue.

Since the active glue is coated on the product to be injected, when the temperature reaches about 70 ℃ ~ 80 ℃, the activity of the active glue will be stimulated to ensure the adhesion between the product to be injected and the silica gel, and to ensure the quality and quality of the product to be injected. performance.

In practice, the products to be injected can be glass products with lines, products with display screens, plastic products with lines, etc., wherein the plastic products with lines can further be transparent plastic products with lines.

In practice, since the above-mentioned products are commonly used and mainstream, and are easy to be understood by those skilled in the art, the above-mentioned products are only used as examples for illustration here; however, the products to be injection-molded provided by the embodiments of the present invention may also be other types of products, Such as polyethylene terephthalate (PET, polyethylene terephthalate) products, etc., the above-mentioned products are only used to teach those skilled in the art how to implement the present invention, but are not meant to be limited to the above-mentioned products.

In practice, the product to be injected may include a display module formed by bonding a display screen and a glass cover.

In practice, the low-temperature liquid silicone injection molding of the product to be injection-molded may be performed through a mold to perform low-temperature liquid silicone injection molding on the display module of the product to be injected.

In practice, performing low-temperature liquid silicone injection molding on the product to be injected may be to perform low-temperature liquid silicone injection molding on the display module of the product to be injected and the equipment casing of the product to be injected through the mold.

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

In practice, the precision after injection molding of the low-temperature liquid silicone can be less than or equal to 0.1 mm.

The low-temperature liquid silicone in the embodiment of the present invention is molded at low temperature, with a thickness of 0.3-0.4mm. After the molding is completed, it just absorbs the lamination tolerance of the screen and the glass cover, ensuring a uniform gap on the surface after the assembly is completed, which meets the normal production requirements. . Therefore, the technical solutions provided by the embodiments of the present invention can be applied to terminal devices that require narrow bezels, no bezels, or waterproof, and can improve the waterproof accuracy of screen protection, so as to solve the problem of anti-drop protection within a small range.

Taking a mobile phone including a display module bonded by a display screen and a glass cover as an example, the process of liquid silicone injection molding will be described below.

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

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

3) Perform silicone injection molding at 70-80°C to ensure product quality and performance, as shown in Figure 4.

After mold injection molding, the circuit between the screen and the touch screen is not affected by the temperature, and the elastic performance of the 30-degree hardness silicone is also guaranteed. Because of the activity of the glue, the bonding force between the silicone and the screen is strong enough and will not fall off. .

The embodiment of the present invention provides a combination method of low-temperature (70°C-80°C) silica gel and glass plate with circuit, silica gel and glass electronic components such as screen, through the technical solution of the present invention, it can be molded at 80°C, and can 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 coated on the edge of the display screen and glass cover, when the temperature reaches about 70°C to 80°C, its activity will be activated to ensure the adhesion between glass products and silica gel. It not only ensures that the screen and TP wiring are not burned out, but also ensures the adhesion between the silica gel and the glass cover and TP, ensuring product quality and performance.

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

Fig. 5 shows a schematic structural diagram of a cross-section of an electronic device with a display screen according to an embodiment of the present invention, and Fig. 6 shows an enlarged schematic diagram of the cross-section, as shown in the figure, may include: a device housing 1 and a display module , the display module includes a glass cover plate (also called a glass panel) 201 and a display screen 202, and the display module is formed by injection molding of the above-mentioned low-temperature liquid silicone, wherein:

The display screen 202 is glued to the glass cover plate 201, and the width of the glass cover plate 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 practice, it may further include: a display screen fixing bracket (or called a backplane fixing bracket) 3 attached to the display screen, and the display module is fixed on the display screen fixing bracket 3 .

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

The use of stainless steel plates and other methods in implementation is because this method is more commonly used and mainstream, and is easy to use/understand by those skilled in the art, so here we take stainless steel plates as an example; however, it is also possible to use other methods in theory, as long as it can be realized The purpose of fixing the display screen is enough. The stainless steel plate is only used to teach those skilled in the art how to implement the present invention, but it does not mean that only stainless steel plates can be used. During the implementation process, the corresponding material and thickness can be determined in combination with practical needs. .

In practice, the display screen may be a light emitting diode (LED, Light Emitting Diode) display, a liquid crystal display (LCD, Liquid Crystal Display) or an organic electroluminescent diode (OLED, Organic Light-Emitting Diode) or the like.

Taking the LCM display screen as an example, the embodiment of the present invention makes the glass cover plate smaller than the LCD display module (LCM, LCD Module) of the liquid crystal display, so that the edge of the display screen is fixed by the device casing instead of the conventional glass cover. Cover to secure the display. In the prior art method of fixing the display screen with a glass cover plate, there is at least a 1 mm tolerance between the display screen and one side of the glass cover plate, and a 1.2 mm tolerance between the glass cover plate and the device housing. Therefore, using the method provided by the embodiment of the present invention, the width of 2.2mm can be saved on one side, and the width of 4.4mm can be saved on the whole device, and it is no longer necessary to print shielding (black) on both sides of the glass cover. or white) area, so that the distance from the display area of the device to the outer edges on both sides of the device is narrowed. Thus, the screen display area of the electronic device can be made larger, or the electronic device with a larger screen can be made narrower and have a better grip.

The embodiment of the present invention adopts the frameless technology. The frame referred to here refers to the shielding area printed on both sides of the glass cover in the prior art. In the embodiment of the present invention, the area of the glass cover is all the display area. Viewed from the front of the device, there are no borders on the left and right sides or very narrow borders. In the embodiment of the present invention, the lines of the display screen can be blocked by silica gel, or the lines of the display screen can be drawn out from the top or bottom of the device (viewed from the front), without the need for frames to block the left and right sides of the electronic device, thereby achieving borderless or The purpose of narrow borders.

Since the electronic device provided by the embodiment of the present invention adopts the above-mentioned liquid silicone injection molding method, the display screen is protected by low-temperature liquid silicone molding technology, so as to achieve the purposes of anti-drop, anti-static, and waterproof. The low-temperature liquid silica gel used in the embodiment of the present invention is molded at low temperature and the thickness of the produced silica gel is 0.3mm-0.4mm (that is, greater than or equal to 0.3mm and less than or equal to 0.4mm), which just absorbs the screen and the glass cover after the molding is completed. The fitting tolerance of the board can be guaranteed within 0.1mm. It is guaranteed to show a uniform gap after the assembly is completed, which meets the normal production requirements.

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

Taking a mobile phone as an example, the embodiment of the present invention can realize the combination of the mobile phone glass cover, the display screen, or a fully bonded glass cover and display screen, with silica gel. As a result, the glass cover and the display circuit are formed within a tolerable temperature range, and the assembly tolerance of the display and glass cover is absorbed, the assembly gap is minimized, and the shock resistance test of the protective screen is realized within 0.4mm.

The embodiment of the present invention provides two methods of making liquid silicone injection molding for electronic equipment:

1. The glass cover plate 201 and the display screen 202 as a whole (that is, the display module) are injection-molded with liquid silicone, and liquid silicone injection is performed around the display module;

Ordinary silica gel or the like can be used between the glass cover 201 and the display screen 202, or the glass cover 201 and the display screen 202 are usually glued together when provided by the manufacturer, and the present invention is not limited to this

2. In the embodiment of the present invention, the glass cover plate 201 and the display screen 202 as a whole (that is, the display module) can also be fixed to the equipment casing 1 by using liquid silicone molding technology.

Of course, in practice, the above two methods can also be combined, that is, after the liquid silicone around the glass cover plate 201 and the display screen 202 is molded, the display module and the device casing 1 are further doubled. Secondary liquid silicone molding.

The following takes the liquid silicone molding of the display module as an example to describe the production and implementation.

1) Perform liquid silicone molding on the display module with the display screen 202 bonded with the glass cover 201 by means of fixtures and molds, as shown in FIG. 7 ;

2) Load the finished display module from the back of the device casing 1, as shown in Figure 8, lay it flat and install it;

3) Install the display screen fixing bracket 3 from the back of the device casing 1, as shown in Figure 9, compact and paste the display module;

4) After the production is completed, the effect picture viewed from the front of the device is shown in Figure 10.

While preferred embodiments of the invention have been described, additional changes and modifications to these embodiments can be made by those skilled in the art once the basic inventive concept is appreciated. Therefore, it is intended that the appended claims be construed to cover the preferred embodiment as well as all changes and modifications which fall within the scope of the invention.

Claims (8)

1. a liquid silicone injection molding method, is characterized in that, comprises the steps: Coat the product to be injection molded with overmolding glue; the glue is an active glue that is active at 70°C to 80°C; After the glue is cured and molded, perform low-temperature liquid silicone injection molding on the product to be injected. The low temperature is 70°C-80°C; the thickness of the silica gel is 0.3mm-0.4mm; the precision after injection molding of low-temperature liquid silicone is less than Equal to 0.1mm. 2. The method according to claim 1, characterized in that, the curing and molding of the product to be injection molded is performed by irradiating the glue with ultraviolet light. 3. The method according to claim 1 or 2, wherein the product to be injected is a glass product with lines, a product with a display screen or a plastic product with lines. 4. The method according to claim 1 or 2, wherein the product to be injection-molded comprises a display module formed by bonding a display screen and a glass cover. 5 . The method according to claim 4 , wherein performing low-temperature liquid silicone injection on the product to be injected is specifically performing low-temperature liquid silicone injection on the display module of the product to be injected. 6. The method according to claim 4, characterized in that, performing low-temperature liquid silicone injection molding on the product to be injection-molded is specifically, performing a process on the display module of the product to be injected and the equipment housing of the product to be injected. Low temperature liquid silicone injection molding. 7. An electronic device with a display screen manufactured by the method according to any one of claims 1 to 6, characterized in that it includes a device housing and a display module, and the display module includes a glass cover and a display screen , the display module is formed by injection molding according to any one of claims 1 to 6, wherein: The display screen is bonded to the glass cover, and the width of the glass cover is smaller than the width of the display screen; The edge of the display screen is fixed to the device casing. 8. The electronic device according to claim 7, further comprising: a display screen fixing bracket attached to the display screen, and the display module is fixed on the display screen fixing bracket.