Manufacturing Audio CDs

1
Manufacturing Audio CDs

• Group C2
• Ellen Cappo, Sarah Shivers, Holly Laird, Ulzie
  Rea, Julian Getachew, Etienne Touissant

2
How CDs Work

• Laser reads pits lands in a binary format
• The data follows an outward spiral path of data
  along the CD, and the laser moves along it while
  the disk is spinning

3
How CDs Are Manufactured

• Step 1 Photoresist Stamper Processing
• Step 2 Injection Molding Stamping
• Step 3 Signal Surface Deposited
• Step 4 Protective Top Coating Label Printing

4
Photoresist Stamper Processing

• Stampers are created for mass-production
• Photoresist is a material that hardens when
  exposed to light. CD features are imprinted in
  with a laser 1.6µ
• The photoresist has a thickness of .12µ with a
  tolerance of .003µ

5
Father and Mother Molds

• Nickel father and mother molds are created by an
  electroforming process

6
Father and Mother Molds
7
Replication Process

• Optical-grade polycarbonate is used
• The mold consists of a stamper mounted on one
  side and a mirror block on the other
• Center hole is punched during cooling
• Cycle time of 12s

8
Layers

• Metal Protection / Reflection
• Metals usually used (aluminum, silver, gold)
• .1 to .15 microns are use to achieve high
  reflectivity
• Acrylic Protection
• Transparent thermoplastic
• Applied by spin coating to ensure an even spread
• Cures fast using UV rays
• Label is placed on the top layer over the
  acrylic