Page 290 - Engineering Plastics Handbook

252 Engineering Plastics

conditions, at one-point gate. It is possible for LCP to flow and fill up
the mold by shearing below its melting point. However, blisters on the
surface of the product may occur by involvement of air or by the remain-
ing distortion of the product caused by jetting in the mold in that case.
4. Mold design. Since the mold shrinkage of LCP is very small, it is easy
to ask for a product size. However, it is necessary to pay great atten-
tion to gate position in designing the mold for LCP, because the weld
strength of LCP is very low, the anisotropy is strong, and the stiff-
ness may vary depending on the thickness of molding due to polymer
orientation.

Consumption. In 2004, global consumption of LCP was considered to
be 19,800 tons/yr. In the market of LCP, electrical and electronic parts,
and office automation (OA), AV parts consume about 87 % and 10 % of
the total demand, respectively (Figure 11.9).

Application
Injection molding. The primary targets for the LCP market are electric
and electronic. And both electric and electronic parts actually account
for more than 85% of the total demand. Recently, demand for super-
miniaturizing design and SMT is increasing. In addition to excellent
heat resistance, outstanding flowability has also been demanded for
polymeric materials these days, and LCP is the only material exhibit-
ing these two characteristics at the same time. The second-largest
market for LCPs is office equipment and precise machines, because
LCPs exhibit reduced mold shrinkage and excellent dimensional sta-
bility due to their low thermal expansion and high modulus.

Others
3%
10%
87% Electrical/electronic
25,000 17,520 19,800
Amount demanded, tons/yr 15,000 17,300 12,700 15,000 World
20,000

10,000

5,000

0 Japan
2000 2001 2002 2003 2004
Figure 11.9 Annual worldwide demand of LCP.