This section contains a summary of the most frequently asked questions about Sumitomo Chemical's High Performance Plastics, in Q & A format. Please do not hesitate to inquire about any other questions you may have that are not listed here.

Inquiry

SUMIKASUPER LCP

Q:

How can I select the most appropriate grade for my application?

A:

First of all, the series to be used must be selected, in accordance with the required heat resistance. Then the type of filler must be selected, in accordance with the shape and purpose of the molded product. It is important not to use a grade that possesses a heat resistance exceeding your requirements. If highly heat resistant grades are utilized, there are more chances for problems to occur, as the greater the heat resistance, the more care and attention required during the molding process.

Q:	How can I estimate the mold shrinkage when designing the mold?
A:	In general, mold shrinkage is based on the mean value of the mold shrinkage in the flow direction (MD) and the mold shrinkage in the transverse direction (TD). MD mold shrinkage can be estimated as a value slightly smaller than the mean value. TD mold shrinkage can be estimated as a value slightly greater than the mean value.

Q:

What is the melting point of SUMIKASUPER LCP? What is the optimum molding temperature ( degree C) for SUMIKASUPER LCP?

A:

There is no obvious melting point for SUMIKASUPER LCP. Adequate strength can only be attained if it is molded at a temperature equal to or greater than the liquid crystal transition temperature. However, excessive molding temperatures may cause problems, such as gas production. Therefore, it is recommended that the molding temperature not be set to a value at the lower limit, but to a median value within the recommended temperature range.

Q:

Are there any grades that possess particularly high weld strength?

A:

It is difficult to increase the weld strength of SUMIKASUPER LCP. The weld strengths of all SUMIKASUPER LCP products, including those made by our competitors, are similarly low. In order to ensure that SUMIKASUPER LCP is utilized in the best manner, it is crucial to move weld areas to places where stresses will not be applied, through a combination of proper production design, grade selection and molding conditions. Please contact our offices for additional details.

Q:	Can SUMIKASUPER LCP be exported freely?
A:	Please ensure that you make relevant inquiries regarding the export of SUMIKASUPER LCP, as the export of certain grades is restricted under Japan's Foreign Exchange Control Law.

SUMIKAEXCEL PES

Q:	How can I select the most appropriate grade for my application?
A:	We produce pellet grades used for injection molding and powder grades used in coating applications and for similar uses. Non-reinforced grades should be used for injection molding applications where transparency is required. Please contact us for assistance in selecting specific grades in accordance with your particular application and molding requirements.

Q:	What is RV?
A:	RV stands for Reduced Viscosity. RV is used as a guideline for the molecular weight of SUMIKAEXCEL PES. The greater the RV value; the higher the molecular weight.

Q:	Is SUMIKAEXCEL PES a transparent resin?
A:	Non-reinforced grades are transparent and have a slightly amber color. Grades containing filler are not transparent.

Q:	Can SUMIKAEXCEL PES be exported freely?
A:	Certain special grades are subject to export restrictions under Japan's Foreign Exchange Control Law. Please ensure that you make the relevant inquiries prior to exporting.

Q:	What kind of precautions should be taken for molding SUMIKAEXCEL PES?
A:	As SUMIKAEXCEL PES absorbs some water, it must be dried thoroughly prior to molding. As well, its Tg (glass transition point) is quite high, at 220 degree C. Therefore, it is important to select the appropriate mold temperature. In particular, it is recommended that the mold temperature be set to 160 degree C or greater for large-sized molded products.

Q:	I am impressed with the performance of SUMIKAEXCEL PES. However, I am also worried that corrosive gases may be produced from corrosion within the mold and from molded products.
A:	There should be no concerns about mold corrosion if molding is performed under the appropriate conditions. Furthermore, the molding of SUMIKAEXCEL PES produces the lowest amounts of gases, including corrosive gases, among all thermoplastic resins.