Highest impact resistance. Key points during the injection molding of polycarbonate.

Representative Applications

As mentioned earlier, polycarbonate's properties and characteristics make it a widely demanded material for everything from everyday items to industrial parts. The specific applications of PC resin based on its properties are as follows:

Applications that utilize transparency:

• Smartphone and camera lenses
• Camera bodies, optical tubes
• Car front lenses and other lighting components
• Decorative parts of pachinko machines

Applications that utilize impact resistance, weather resistance, and high heat resistance:

• Highly impact-resistant helmets
• Outdoor building materials such as terraces and carports
• Unbreakable cups, cooking utensils
• Used as material for the ball path inside pachinko machines by adding carbon to enhance conductivity

Differences between Polycarbonate and Acrylic Sheets:

Polycarbonate (polycarbonate) and acrylic sheet (acrylic sheet) are the same type of plastic but have some differences in special features and applications.

For example, polycarbonate is used in a wide range of applications including construction, automotive, and electrical/electronic devices due to its excellent impact resistance, heat resistance, and chemical resistance. However, its transparency is inferior to that of acrylic sheets. In contrast, acrylic sheets have higher transparency and excellent water resistance and oxidation resistance. They are used for display, signs, and advertising exhibition designs. However, their impact resistance and heat resistance are inferior to polycarbonate.

Points to Note During Molding of Polycarbonate:

When molding polycarbonate, there are various points to consider to prevent defects during various operations, as mistakes in the following tasks can easily lead to defects.

During Material Preparation:

• Pre-drying is necessary before molding (4 hours at 120°C). Undried polycarbonate may cause silver streaks when molded.

During Heating Cylinder / Mold Temperature Setting:

Heating Cylinder:

Set around 300 degrees. If thread pulling is strong, lower the heating cylinder nozzle temperature.

Mold:

Set above 80 degrees. Low mold temperatures cause poor flow, leading to short shots and sink marks.

Common Visual Defects:

Silver Streaks:

High-speed filling makes silver more likely to appear.Be cautious when the mold's structure is complex, involving bosses or ribs.

Knit Lines:

Lowering the fill speed and properly venting gas can reduce weld lines, especially at points where multiple gate mold flows converge or wrap around ribs or bosses.

Mold Release Defects:

Due to its high transparency, polycarbonate is prone to mold release marks. Inspect and adjust holding pressure, ejection balance, and ejection speed.

Voids:

High transparency makes vacuum voids in thick sections noticeable. Adjust holding pressure and time as basics. If that does not improve, machining meat theft in the mold can be effective.

Splay Marks:

Increasing the fill speed or processing gas vents in the mold can improve splay marks at the flow front.

Adsorption Dirt:

Dirty adsorption pads on the handling equipment can contaminate the product surface. Regular cleaning of adsorption pads is necessary.

Summary:

Polycarbonate, a representative engineering plastic material, excels in impact resistance, durability, heat resistance, and moldability. However, due to its characteristics, it requires attention to various points during molding. Consider the factors mentioned above to aim for more productive molding.