DNP has achieved "roll-to-roll" processing that enables continuous mass production of high-quality optical film products by utilizing its proprietary advanced "web handling" and highly productive "inline multi-layer coating" technologies.

• What is roll-to-roll?
• What is web handling?
• What is inline multi-layer coating?
• DNP's optical film - strengths in manufacturing processing
• DNP's optical film

"Roll-to-roll" is a production method in which a film substrate unwinds from a roll, passes through processing devices, then rewinds onto another roll to create a product. This method enables continuous film processing, resulting in high productivity and lower costs compared to individually processing cut film substrates in a single-wafer form. However, due to the continuous processing, there are certain restrictions on processing conditions which present production challenges. Nevertheless, DNP has successfully implemented "roll-to-roll" processing by employing advanced "web handling" and highly efficient "inline multi-layer coating" technologies.

A thin, sheet-like material such as film is referred to as a "web." Web handling is the technology to transport a web without causing wrinkles or scratches, as well as rewinding and storing it without inducing miswinding or wrinkling. DNP has pioneered technologies for analyzing crucial values like "transport tension" to prevent film from scratching or slipping on guide rolls, the "pressing pressure" within the nip, and the "take-up tension" to avoid miswinding.
Furthermore, we have developed proprietary technologies for high-speed roll winding, allowing production under optimal process conditions that takes under consideration the thickness and type of film.

The inline multi-layer coating method involves continuously applying multiple layers onto a film substrate between unwinding and winding. This technology allows DNP to produce multi-layer coated products in a single pass through the production line. This approach minimizes the risk of foreign matter adhering to the film and significantly enhances productivity compared to processes requiring multiple passes through the line.

DNP leverages its accumulated optical design expertise to optimize properties like transparency, reflectance, and contrast for optical films. Additionally, various functions such as hardness, anti-scratch, adhesion, durability, and antistatic properties can be added according to customer's requirements.

Careful consideration of ink material design is vital. To avoid issues like ink repulsion, uneven thickness, or insufficient hardness, the ink's physical properties and characteristics, like viscosity, need attention. DNP crafts its own inks, ensuring high-quality lamination and swift development of film products meeting even complex demands like multi-layer coating.

The inline multi-layer coating technology is essential for delivering high-performance, top-quality optical films like AR/AG films at affordable prices. With multi-layer coating capabilities of up to three layers, DNP can mass-produce optical films boasting features such as anti-glare, contrast enhancement, anti-static, hard-coating, and low reflection.

Available in 2500mm width
DNP's production lines accommodate up to 2500mm width, meeting the demand for larger LCDs. While maintaining uniform coating thickness on wider products poses challenges, DNP's advanced processing technology ensures even coatings.

High quality even with mass production
For mass-produced wide optical films, DNP employs the roll-to-roll process, achieving high productivity alongside advanced quality via meticulous process technology and defect-detecting inspection machines.

The functional layer of optical film is thin, ranging from several hundred nm to several microns in thickness, and strict quality control is required as the presence of even the smallest dust particles can result in defective products. DNP manufactures optical film in clean rooms with strict entry control everywhere from unwinding to winding, and maintains a high level of cleanliness, especially in the coating and drying processing equipment.

AR film, and LR film(Low-reflection film) are optical films with an anti-reflection layer. By taking advantage of light interference at the AR layer, reflected light can be reduced on a screen, and its transmittance can be improved.
AR film reduces the effects of ambient light on display screens and allows them to be seen more clearly.

AG film reduces outside light reflection by diffusely reflecting incident light on an uneven surface, distinct from AR film utilizing light interference. AG film uses a hard coat layer with deposited particles on the base film to achieve its effect, unlike AR film which relies on light interference. These films can even be combined for further reduced ambient light reflection.

At DNP, we have a wealth of expertise in the design and manufacturing of optical film such as AR film and AG film. Please contact DNP for optical film development and manufacturing. With DNP, various proposals are possible to meet your specific needs.