Two substrates bonding type optical disk and method of producing the same

A method of producing an optical disk comprising:

• a step of preparing a first partial structure by forming a first optical film, which partially transmits an incident light beam, on a first pit-groove surface of a first transparent substrate in which the first pit-groove surface is provided with first pits or grooves carrying first information signals;
• a step of preparing a second partial structure by forming a second optical film on a second pit-groove surface of a second substrate, in which the second pit-groove surface is provided with second pits or grooves carrying second information signals and in which each of second pits or grooves is formed into a shape capable of being read by irradiating the second substrate with a light beam from a second pit-groove surface side on the second substrate;
• a step of bonding the first and the second partial structures together by laminating a dry photohardenable film of light transmissive type, which has a viscosity of 3,500 to 400,000 poises at a room temperature and in a non-hardened condition and has a thickness of 5 to 200 .mu.M in the non-hardened condition, between the first and the second partial structures with the first optical film side of the first partial structure and the second optical film side of the second partial structure disposed opposite to each other to form a layered product, and by pressing the layered product from one end toward the other end thereof while passing through and between an over roll and an under roll to apply a pressure with the over roll and the under roll of 0.5 to 50 kg/cm.sup.2 ;
• and
• a step of hardening the dry photohardenable film in the layered product by irradiating the layered product with ultra-violet light from a first transparent substrate side of the layered product, while pressing the layered product.

A method of producing an optical disk comprising:

• a step of preparing a first partial structure by forming a first optical film, which partially transmits an incident light beam, on a first pit-groove surface of a first transparent substrate in which the first pit-groove surface is provided with first pits or grooves carrying first information signals;
• a step of preparing a second partial structure by forming a second optical film on a second pit-groove surface of a second substrate, in which the second pit-groove surface is provided with second pits or grooves carrying second information signals and in which each of second pits or grooves is formed into a shape capable of being read by irradiating the second substrate with a light beam from a second pit-groove surface side on the second substrate;
• a step of bonding the first and the second partial structures together by laminating a dry photohardenable film of light transmissive type, which has a viscosity of 3,500 to 400,000 poises at a room temperature and in a non-hardened condition and has a thickness of 5 to 200 .mu.M in the non-hardened condition, between the first and the second partial structures with the first optical film side of the first partial structure and the second optical film side of the second partial structure disposed opposite to each other to form a layered product, and by pressing the layered product from one end toward the other end thereof while passing through and between an over roll and an under roll to transport said layered product with the over roll and the under roll at a speed of 0.05 to 10 meters/minute;
• and
• a step of hardening the dry photohardenable film in the layered product by irradiating the layered product with ultra-violet light from a first transparent substrate side of the layered product, while pressing the layered product.