Method and apparatus for bonding optical disc substrates together, and method for supplying liquid material

A method for bonding two optical disc substrates which comprises steps of:

• supplying adhesive onto only one of said optical disc substrates in a ring shape,
• joining said optical disc substrates with said adhesive while forming an electric field between said optical disc substrates;
• spinning the joined optical disc substrates, and
• curing said adhesive.

A method for bonding two optical disc substrates which comprises steps of:

• supplying adhesive onto one of said optical disc substrates in a ring shape and onto the other of said optical disc substrates so as to cover most of a surface thereof,
• joining said optical disc substrates with said adhesive while forming an electric field between said optical disc substrates;
• spinning the joined optical disc substrates, and
• curing said adhesive.

A method for bonding two optical disc substrates which comprises steps of:

• supplying adhesive onto one of said optical disc substrates in a ring shape and onto the other of said optical disc substrates in a circular shape by dots at a relatively small spacing,
• joining said optical disc substrates with said adhesive while forming an electric field between said optical disc substrates;
• spinning the joined optical disc substrates, and
• curing said adhesive.

A method for bonding two optical disc substrates which comprises steps of:

• supplying adhesive onto only one of said optical disc substrates in a circular shape by dots at a relatively small spacing,
• joining said optical disc substrates with said adhesive while forming an electric field between said optical disc substrates;
• spinning the joined optical disc substrates, and
• curing said adhesive.

A method for bonding two optical disc substrates which comprises steps of:

• supplying adhesive onto one of said optical disc substrates in a circular shape by dots at a relatively small spacing and onto the other of said optical disc substrates so as to cover most of a surface thereof,
• joining said optical disc substrates with said adhesive while forming an electric field between said optical disc substrates;
• spinning the joined optical disc substrates, and
• curing said adhesive.

A method for forming an optical disc comprising steps of:

• supplying an adhesive onto one of two optical disc substrates,
• setting said optical disc substrates so as to face a liquid film of said adhesive which was supplied onto one of said optical substrates toward the other of said optical disc substrates;
• forming an electric field between said optical disc substrates so as to taper a surface of said liquid film toward the other of said optical disc substrates in order to reduce an initial contact area between said surface of said liquid film and the other of said optical disc substrates for preventing generation of voids in said liquid film, and
• joining said optical disc substrates with said adhesive while forming said electric field between said optical disc substrates.

A method for forming an optical disc comprising steps of:

• supplying an adhesive onto one of two optical disc substrates, respectively,
• setting said optical disc substrates so as to face a liquid film of said adhesive which was supplied onto one of said optical substrates;
• forming an electric field between said optical disc substrates so as to taper a surface of said liquid film which was supplied onto one of said optical disc substrates toward said liquid film which was supplied onto the other of said optical disc substrates in order to reduce an initial contact area between said liquid films for preventing generation of voids in said liquid films, and
• joining said optical disc substrates with said adhesive while forming said electric field between said optical disc substrates.