Method for producing holographic recording medium

Abstract

A method for producing a holographic recording medium having a holographic recording layer between a first substrate and a second substrate including the steps of: providing a holographic recording layer forming composition onto the first substrate, forming the holographic recording layer between the first and substrate and the second substrate by facing the second substrate to the first substrate, and hardening the holographic recording layer by at least one of heat and light.

1 - 45 . (canceled) 
     
     
         46 . A method for producing a holographic recording medium having a holographic recording layer between a first substrate and a second substrate comprising the steps, conducted sequentially in the following order, of:
 forming a space between the first substrate and the second substrate and enclosing the space with an inner side space retaining member and an outer side space retaining member to retain a designated distance between the first and second substrates, wherein one of the inner side space retaining member and the outer side space retaining member has at least one opening through which a holographic recording layer forming composition is charged into the space on the condition of holding the first substrate and the second substrate so that the designated distance is retained between the substrates,   reducing pressure in the space by a pressure controlling means,   charging the holographic recording layer forming composition into the space through the at least one opening to form the holographic recording layer; and   hardening the holographic recording layer by at least one of heat and light.   
     
     
         47 . (canceled) 
     
     
         48 . The method of  claim 46 , wherein the step of the charging comprises the holographic recording layer forming composition into the space while the reduced pressure in the space is maintained. 
     
     
         49 . The method of  claim 46 , further comprising the steps of:
 holding the first substrate by a first substrate holding member;   holding the second substrate by a second substrate holding member; and   wherein the step of forming the space comprises the step of:   facing the second substrate held by the second substrate holding member to the first substrate held by the first substrate holding member.   
     
     
         50 . The method of  claim 49 , wherein the first substrate and the first substrate holding member are brought in contact with each other by vacuum. 
     
     
         51 . The method of  claim 50 , wherein the second substrate and the second substrate holding member are brought in contact with each other by vacuum. 
     
     
         52 . The method of  claim 49 , further comprising the step of:
 providing the inner side space retaining member and the outer side space retaining member between the first substrate and the second substrate during the step of facing the second substrate to the first substrate.   
     
     
         53 . The method of  claim 46 , further comprising the step of:
 removing the holographic recording layer forming composition forced out from the area of facing the second substrate to the first substrate.   
     
     
         54 . The method of  claim 46 , further comprising the step of:
 cutting the holographic recording medium into a designated size after the step of hardening.   
     
     
         55 . The method of  claim 46 , further comprising the step of:
 sealing the bare portion of the holographic recording layer.   
     
     
         56 . The method of  claim 46 , wherein the holographic recording medium satisfies the relation of 0.15≦Dh/(D1+D2)≦2.0 wherein D1 is the thickness of the first substrate, D2 is the thickness of the second substrate and Dh is the thickness of the holographic recording medium. 
     
     
         57 . The method of  claim 56 , wherein the thickness of the holographic recording layer Dh is from 200 μm to 2.0 mm. 
     
     
         58 . The method of  claim 56 , wherein the relation of the thickness of the first substrate D1 and the thickness of the second substrate D2 is D1≦D2. 
     
     
         59 . The method of  claim 46 , wherein the first substrate is transparent and subjected to an anti-reflection treatment on the side opposite to the side on which the holographic recording layer is provided. 
     
     
         60 . The method of  claim 46 , wherein the material of the first substrate is glass. 
     
     
         61 . The method of  claim 46 , wherein a reflective layer having a reflectance of not less than 70% is provided on the at least one of the face of the second substrate on which the holographic recording layer to be provided and the face opposite thereto. 
     
     
         62 . The method of  claim 46 , wherein the shape of the holographic recording medium is a disc. 
     
     
         63 . The method of  claim 46 , wherein the shape of the holographic recording medium is a card. 
     
     
         64 . The method of  claim 46 , further comprising the step of:
 removing a bubble included in the holographic recording layer formed by the step of forming.   
     
     
         65 . The method of  claim 46 , wherein the step of reducing pressure includes a step of placing an empty recording medium in which a recording layer forming composition is not charged into the space in an enclosed room and a step of reducing pressure in the enclosed room such that the pressure in the space is reduced. 
     
     
         66 . The method of  claim 46 , wherein the step of charging comprises the steps of:
 immersing the opening into the holographic recording layer forming composition; and   restoring the pressure in the enclosed room to the original pressure by the pressure controlling means to charge the holographic recording layer forming composition into the space.