Laboratories of Innovation in Adhesive Materials develop adhesion-related products in the Oji Group.
Example of Composition of a Display with a Touch Panel and Our Major Products under Development
Major developed products
(1) Highly gap filling, optically clear double-sided adhesive sheet
Features both conflicting advantages: gap filling and durability
Highly transparent, optically clear double-sided adhesive sheet is mainly applicable to the adhesion of materials for touch panels on smartphones, tablets and other devices.
These sheets require excellent performance in many different aspects, such as the prevention of lTO corrosion, low-dielectric constant, reworkability, gap filling and durability. In particular, using a thin adhesive sheet to flexibly follow gap in frame ink step and circuits is a big issue.
To satisfy both conflicting requirements, gap filling (softness) and durability (cohesion), the Oji Group developed a dual-cure adhesive sheet that softens when adhered and hardens after adhesion by undergoing UV irradiation.
(2) Low-dielectric optically clear double-sided adhesive sheet
Prevents a touch sensor from malfunctioning caused by internal electromagnetic noise
The touch panel reads the slight changes of electrostatic capacity between electrodes and identifies touched positions very accurately.
However, a change in the electrostatic capacity between electrodes may be affected by the electromagnetic noise from an internal device and cause a sensor malfunction or the deterioration of its sensitivity.
The Oji Group developed a low-dielectric, optically clear double-sided adhesive sheet to inhibit the effects of the electromagnetic noise.
Internal electromagnetic noise continues to increase in parallel with advances in communication standards. The product is available in many different types※ and flexibly addresses new demand from customers.
*Both UV irradiation required type, and no UV required type available.
(3) Highly durable, optically clear double-sided adhesive sheet
High durability to many different film materials
An automobile is equipped with numerous displays such as in a car navigation system. Each display has a highly transparent, double -sided adhesive sheet within. The adhesive sheet must be sufficiently durable to continuously withstand harsh environments such as temperature extremes.
Using its original technology for resin design, the Oji Group developed a highly durable, optically clear double-sided adhesive sheet free from lifting, peeling, yellowing and other changes in appearance even if used with many different types of film (such as PET and TAC) or under severe conditions in an automobile.
(4) Colored, optically clear double-sided adhesive sheet
The highly transparent color in the double-sided adhesive sheet projects an upscale feel to the appearance
Using its original technologies for coating and dispersion, the Oji Group developed a colored, optically clear double -sided adhesive sheet.
Despite being colored, the sheet is highly transparent and can vividly represent the displayed image as is.
In addition, it can characteristically add an upscale feel to the interior by making it better assimilated into the bezel of the display when the light of the car navigation system is on or off.
(5) Outgassing resistance optically clear double-sided adhesive sheet
The optically clear double-sided adhesive sheet that resists outgassing from resin materials
The outermost layers of devices such as smartphones and car navigation systems increasingly involve the use of resin plates, such as polycarbonate, instead of glass for the purpose of weight reduction and prevention of breakage. For improvements in designability, the use of curved, molded resin materials is also considered.
Use of such resin materials may lead to outgassing with the passage of time and may result in bubbles or peeling.
As an advanced form of the dual cure-type adhesive sheet, the Oji Group developed an optically clear double-sided adhesive sheet that is durable under temperature extremes and also capable of suppressing the occurrence of outgas from resin materials.
(6) UV-Cut optically clear double-sided adhesive sheet
Prevents deterioration of components used outdoors due to ultraviolet rays.
Displays and touch panels for outdoors are exposed to sunlight for a long period of time. Even if ultraviolet rays (UV) durable glass is used for the outermost layer, the internal components may be deteriorated by UV passed through the glass. In addition, UV deterioration may be a problem for thin-display mobile products.
The Oji Group has developed an optically clear double-sided adhesive sheet that has both UV cut performance and adhesive performance required for bonding touch panel display parts. The sheet prevents troubles due to long-term UV exposure.
(7) High-retardation, anti-scattering film
Eliminates Rainbow-Mura and enhances visibility
Touch panels are becoming more common for the displays of car navigation systems, instrument panels and other automobile-related devices and materials.
Using polarized sunglasses while driving may induce rainbow-mura because of a phase difference from the display, which may result in poor visibility.
By controlling the phase difference in an anti-scattering film, the product makes it possible to minimize Rainbow-Mura.
(8) Anti-watermark film
Prevents film from adhering to LC module without compromising image quality
As touch panel modules become lighter in weight, thinner and larger, they can easily warp when touched by a finger. This gives rise to the increased occurrence of a watermark, which is caused by a touch panel adhering to a liquid crystal module.
To solve the problem, the Oji Group developed anti-watermark film, which, through the special concave-convex structure of the film, neither adheres nor compromises the image quality of the liquid crystal.
In addition, we develop functional films with many different features.
They are designed to meet users’ needs, such as control of the refractive index difference of light to minimize glare on the image, prevention of flaws, smooth movement of fingers on the surface and prevention of dirt.