Leading in Optical Bonding

What is Optical Bonding

Optical bonding is the process of filling up the airgap between the cover glass / touch panel and LCD cell / module to improve the visual and material features and with that the quality and value of the bonded device.

CLEAR-BOND uses silicone based liquid adhesive with the best properties available to date for this process.




The silicone-glue formula used is the faytech-X2-1688, also known as 'CLEAR-BOND'. This formula has been specifically created to provide the best optical bonding performance in the market.


This silicone-glue formula consists of two components, referred to in the documentations as component A and B.

The silicone liquid AB-glue is especially suitable for: Large size optical bonding

Optical bonding to be used in extreme environments:


CLEAR-BOND produces its glue in Tongling, China, under the highest quality standards. Every single batch is tested to meet the highest  quality  criteria, which  guarantee the flawless optical bonding mass production.

>100 ton/year

With more than 100 ton of yearly glue production, CLEAR-BOND is the leading supplier of glue for large format optical bonding.

Services & projects

CLEAR-BOND focuses on all bonding related services & projects and is a separate business unit and registered trademark of faytech, the first  company bringing a large format optical bonding process into mass production.

Mechanical Test

 Test Item  Measuring Method  Test Condition  Result
 Vibration Test  MIL-STD-810F  1 hour  No bubble or delamination
 Shock Test  MIL-STD-810F  40g, 11ms pulse ±X, ±Y, ±Z axes
 Altitude  -  15,000 feet above sea level, climb / descent change rate 10m/s decompression withing 15 seconds
 Pull Test  GB/T 1040.2-2006  Force until separation  0.278 N/mm2
 Lap Shear Test  GB/T 1040.2-2006    0.205 N/mm2
Test Item Measuring Method
High Temperature MIL-STD-810-2003
Low Temperature MIL-STD-810-2003
Constant Temperature & Humidity IEC 60068-2-78-2012
Thermal Cycle IEC 60068-2-78-2012
UV Resistance G154-06
Mechanical Shock MIL-STD-810F
Vibration MIL-STD-810F

Besides the 'CLEAR-BOND' formula faytech-X2-1688. There are 2 other standardized formulas in the market, allowing the client to pick the best bonding glue to suit their needs:




Specifically created for low temperature applications of below -50 °C


Softer formula, allowing more flexibility


Additionally, faytech would be able to adapt the materials properties, such as hardness, viscosity, curing speed, etc., upon request.
This is done due to possessing their own silicone formulations and own in-house production.


faytech-X2-1688 'CLEAR-BOND'
Standard formula – 1:1 ratio (component A and B). Specifically created to provide the best optical bonding performance in the market. Adjustable to a certain extend by adjusting the mixing ratio.

Softer formula, allowing more flexibility.

Specifically created for low temperature applications of below -50 °C.

Advantages of Optical Bonding

reduced by about

increased by about

No humidity or dust
is able to enter between the touch panel and LCD cell

Additional resistance
towards environmental forces onto the glass


CLEAR-BOND bonding facilities and service

There are two class 100 cleanrooms available in Shenzhen and Suining in order to perform the optical bonding services.

The production area consist of 5000+ sqm altogether and has a daily optical bonding output of >500 large formats.

CLEAR-BOND provides in-house optical bonding services of cover glass / touch panel to open cell / LCD-Modules of sizes all the way up to 105 inch!

CLEAR-BOND machinery

CLEAR-BOND completely developed own bonding machinery and unique processes for large format bonding. These processes offer an outstanding production yield of 97%.

A total of three different bonding processes are available, those for small, middle and large formats. Besides this, other bonding processes include those for display modules and cells.


Services for manufacturers

CLEAR-BOND provides training, machinery and glue to world leading (touch) device and whiteboard manufacturers in order to support their in-house optical bonding production.

Tailored solution

CLEAR-BOND provides a tailored solution of German dispensers & equipment, self-developed machineries and processes (patented) together with experienced project managers.

CLEAR-BOND glue production

CLEAR-BOND is produced within the clean room using high quality containers and equipment.

Samples of all production lots are stored and secured over long periods of time while being tested on a regular basis for stability and conformity (temperature, consistency, pull & shear test, haze, etc.).

CLEAR BOND Production
CLEAR BOND Production
CLEAR BOND Production

CLEAR-BOND Technical Data


Cured Mixture of components - faytech-X2-1688 - 'CLEAR-BOND'

Typical Characteristics Measuring Method Value
Color - Clear
Yellowing Index ASTM E313-15e1 <1
Density at 23 °C ISO 2781 0.97 g/cm³
Penetration (150 g hollow cone) DIN ISO 2137 220 ±20 mm/10
Relative Permittivity IEC 60250 2.7
Dielectric Strength  GB/T 1693-2006 400 µm/m°C 
Volume resistivity  GB/T 1692-92 1015 Ω cm
Surface resistivity  IEC 93 1014 Ω 
Refractive index nD25  1.404
Flame retardancy  - 94 HB 
Transmission (path length 1.5 mm)  - > 98.9 % 
Thermal conductivity  GB/T 10297-1998  0.20 W/m K 
Coefficient of linear thermal expansion  ISO 11359 - 1- 2014 300 x 10-6 m/m K 
Temperature Range  - -40 to 85 °C 
Shrinkage  - < 0.1 % 



Uncured components A and B - faytech-X2-1688 - 'CLEAR-BOND'

Typical Characteristics  Measuring Method Value
Color  - Clear
Viscosity at 23 °C  ISO 3219  Typ. 1000 mPas  Min. 800 mPas; Max. 1200 mPas
Density at 23 °C  ISO 2781 0.97 g/cm³ 
Haze  ASTM D 1003 < 0.3 % 

Catalyzed Mixture of components A + B - faytech-X2-1688 - 'CLEAR-BOND' 

Typical Characteristics  Measuring Method  Value 
Platinum-catalyst in component -
Mixing ratio  A : B  1 : 1 
Viscosity of mixture  ISO 3219 1000 mPas  Min. 800 mPas; Max. 1200 mPas 
Pot life at 23 °C  - 150 min 
Curing method  - Hydrosilylation 

Uncured components A and B - faytech-T50-1688

Typical Characteristics  Measuring Method  Value 
Color  - Clear 
Viscosity at 23 °C  GB/T 10247-2008 typ. 500 mPas 
Density at 23 °C ISO 2781  0.99 g/cm³ 
Haze  ISO7027-1999  < 0.2 % 

Catalyzed Mixture of components A + B - faytech-T50-1688

Typical Characteristics  Measuring Method  Value 
Mixing ratio  A : B  1 : 1 
Pot life at 23 °C  - > 2h 

Cured Mixture of components - faytech-T50-1688

Typical Characteristics Measuring Method Value
Color  - Color 
Density at 23 °C  ISO 2781  0.99 g/cm³
Penetration (Needle)  GB/T269 240 ±15 mm/10
Relative Permittivity  IEC 60250  2.7 
CTE  GB/T 20673-2006  400 µm/m°C 
Dielectric Strength (25°C)  GB/T 1693-2007  20 kV/mm 
Dielectric Constant (25”C)  GB/T 1693-2007 <3.0 (1MHz) 
Refractive index  nD25  1.404 
Transmission (path length 1.5 mm)  UV-VIS  > 99 % 
Thermal conductivity  GB/T 10297-1998  0.20 W/m K
Temperature Range  - -60 to 140 °C 
Shrinkage  - < 0.1 % 





2nd Floor, plant No.2, Xingye Science Park, Huiyang District,

Huizhou City, Guangdong Province, China