Polyvinyl Butyral Film

Polyvinyl Butyral Interlayer (Winlite®, PVB Film)

For MSDS click here

WINLITE® is produced by extrusion using PVB resin, plasticizer
and additives. It possesses excellent physical properties such as
toughness at high elasticity, superb transparency, weatherability,
impact-resistance at low temperature, optical characteristics, and
optimal adhesive ability to glass. WINLITE® finds major use in
the manufacturing of laminated safety glass for automotive and
architectural application.

Advantages of vertical integration
VAM, PVA, PVB, and plasticizer are upstream raw materials of
WINLITE® and all of them are CCP group's products. That means
raw materials are not only supplied sufficiently but also with good
quality under control. Thus, WINLITE® is very competitive in the
market.

Polyvinyl Butyral Resin
The base material for WINLITE®, PVB resin, is a thermoplastic
macromolecular compound obtained by condensation reaction of
polyvinyl alcohol and butyraldehyde. This resin shows excellent
flexibility, film-forming and optimal adhesion properties.

Plasticizer
The plasticizer used in WINLITE® PVB film has
following characteristics:
■ Excellent compatibility to PVB resin
■ Excellent heat resistance
■ Superior weatherability
■ No discoloration
■ Low volatility

According to customers' demand, we offer two types of
WINLITE® PVB film: refrigerated and PE interleaved type. The
sizes are shown as the table below.

Safety
Laminated glasses with WINLITE® act as a good barrier: strongly
it has to absorb mechanical shock. If such an impact is extremely
high, the glass layers may even break; but the resulting splinters
sufficiently have to adhere to the surface of WINLITE® of the
safety glass. This way, personal injury is broadly avoided.

Typical configurations of laminated glass:
≧3mm Glass / 0.76mm WINLITE®/ ≧3mm Glass
≧3mm Glass / 0.38mm WINLITE®/ ≧3mm Glass

Anti-bandit and bullet resistance glass obtained by increasing
WINLITE® thickness or number of layers. The result of “impact
test” of laminated glass (3mm glass/0.38mm WINLITE®/ 3mm
glass) is as shown below. It is clear that the splinters are
adhesive on film without penetration.

Soundproof
Laminated glass offers improved sound barrier effect. Public
places, especially where are noisy, therefore were constructed
with laminated glass windows.

Absorption of UV Rays
Ultraviolet ray may generally cause deterioration of furniture,
pictures, paints, textile goods, etc. Laminated glass using
WINLITE® PVB film is able to absorb nearly 100% of UV ray to
prevent such problem.

Color
Tinted WINLITE® provides the architect or interior designer
various choices to fulfill their ideas.

Preparation: Stretch and Cutting
Considering the deformation of the PVB film during the lamination
process, it should be cut in a way little over sizing the glass area.
In the case of windshield glass, stretching by heating the PVB film
to conform to the shape is needed. To prevent the residual
stress causing contraction, PVB film is suggested to be stored up
below 25℃.

Relative Humidity and Equilibrium Moisture Content
A key factor affecting the adhesion and penetration resistance of
laminated glass is the moisture content of PVB film. It shall be
controlled in the range of 0.3~0.6wt %, but it changes easily by
environment. The following figure shows the equilibrium moisture
content from different relative humidity ranges. When the PVB
film is stored and assembly in a controlled condition of 20℃ and
relative humidity 23% , it will reach an equilibrium and ideal
moisture of 0.4%.

Pre-pressing
Main methods for pre-pressing are nip roll
system and vacuum system. The main proposes are,
◆ De-gassing between glass and PVB film.
◆ Promoting the adhesion of the PVB film to the glass surface.
◆ Sealing the edge of laminated glass to avoid penetration of gas
during autoclave process.

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