3M VHB tape - A Reliable Onboard Display System Bonding Assistance

“With the development of intelligent, networked and electric vehicles, it has brought a profound impact on the development of cockpit electronics. On-board display plays an important role in the cockpit electronics”

Car display has reflected the development trend of large screen, multi-screen and intelligent. At present, the size of the mainstream display has developed to 10 inches-15 inches, which has made considerable development than earlier years, and the size of the central control screen under development has a significant increase trend, equipped with 20 inches, 25 inches, or even more than 30 inches of large screen new cars are emerging in the market. In the modeling design of the display screen is also constantly innovative, from the number of single screen, double screen, triple screen, and even multi-screen linkage. From the form there are floating screen, curved screen, special-shaped screen, rotating screen and so on. At the same time, in order to meet the convenience and visibility of human-computer interaction, the display range is getting larger and larger, and the screen border is getting narrower and narrower.

Compared to the previous small built-in display screen, the fixation of the front glass panel and frame of the large on-board display system becomes particularly important. First, the trend of large screen increases the visualization area, resulting in narrower borders that can be used for fixation. This puts forward high requirements for the strength of the fixed scheme, which needs to be able to resist the stress caused by the deformation of the back frame size of the large screen, and keep the overall display screen flat without warping. Secondly, the use of a large number of large-size suspension screen, in the possible vehicle impact, in the case of a rapid increase in instantaneous acceleration, the screen adhesion firmly, no cracking or falling off. Third, the production of the car screen is an assembly line operation, which requires a high convenience of use, the production cycle should not be too long, and can not pollute the environment. Finally, the vehicle is sometimes placed in the outdoor environment for a long time, but also need to have a certain solar aging resistance, high temperature resistance. Also need to have a leakage prevention of light, waterproof sealing and other characteristics.

So what is 3M's solution as a leading supplier of materials for such complex and demanding requirements?

3M VHB tape can solve these new challenges presented by vehicle display on large screen.3 MVHB tape is the acrylic foam tape first invented by 3M company in the 1980s. By 2020, it has been listed for 40 years. In these 40 years, the length of production and sales worldwide has reached 8.4 billion meters! This length is 10 trips from the Earth to the moon!

The biggest characteristic of VHB tape is the integrated acrylic adhesive component, which has the characteristics of viscoelastic body. When deformation is produced by external force, the foam core layer of VHB can fully absorb the stress generated by deformation and can withstand deformation at least three times its own thickness. And the VHB tape can firmly attach the screen to the frame when the display screen and back frame of the on-board display system are deformed, or the impact occurs during driving.

-Wide applicability and durable adhesive strength of VHB tape

Intelligent vehicle central control display system needs a variety of types of adhesive materials, including aluminum alloy, stainless steel, PC-ABS, ink glass, pure glass and so on, which requires the adhesive scheme to have a wide range of applicability.3M VHB tape system is rich, can meet a variety of high, medium, low surface energy material bonding requirements, while there are a variety of thickness and color to choose from. In the test of 3M laboratory, VHB tape shows high bonding applicability for the above materials, and the bonding strength meets the design requirements of durable bonding.

-The VHB tape can meet the requirements of natural aging resistance and high and low temperature

The environment of the car where the car display screen is located will have a hot summer weather, and the highest temperature in the car will sometimes reach more than 80℃. At the same time, there is also the aging effect caused by ultraviolet radiation. The acrylic structure of VHB tape has good resistance to ultraviolet aging and high and low temperature. After more than 5 years of aging in the Minnesota outdoor aging field, the adhesive relay retention force of VHB tape reached more than 100%. The bond strength of the VHB was largely maintained after up to 1000 hours of 85℃ / RH 85% testing performed in the 3M aging laboratory.

In addition, the 3M VHB tape GPH series is specially designed and developed for higher grades of temperature resistance requirements, and its short-term temperature resistance can reach 230℃ and long-term temperature resistance can reach 150℃. In the static suspension test, under normal temperature conditions, it can reach 0.5 in², 1000g over 100,000 minutes under the area, 177℃, 500g over 10,000 minutes under 0.5 in² area.

-The VHB tape meets the requirements of a waterproof seal

One big trend in smart cockpit systems is the combined use of large screens and multiple screens. Compared to previous built-in display systems, large and multi-screen applications increase the chance of exposure to the external edge of the screen, and in order to ensure the stability of the electronic system, water, water vapor and dust as much as possible. In addition, in daily use, there are also requirements to prevent drinks and other liquid splashing. The foam core of VHB tape is an independent closed foam structure, which can effectively isolate the passage of water vapor and has good waterproof sealing.

-The VHB tape meets the requirements of fast fitting and fast molding

The production enterprises of on-mounted display screen are mostly the operation mode of assembly line, and the general production efficiency is very high. The whole process can not have too long cycle, which requires simple use and rapid installation and forming. VHB tape belongs to the pressure sensitive adhesive (pressure sensitive adhesive, PSA), which is very consistent with the requirements of this operation. The bonding strength can be established only through simple pressure pressing, saving time and cost. At the same time, VHB tape is a fixed thickness of adhesive tape, good die cutting, can be cut according to the shape of customers, which also greatly improves the production efficiency of customers.

Resource from wesite: https://www.3m.com.cn/3M/zh_CN/bonding-and-assembly-cn/bonding_news/newbizopp20210525/