Mold for manufacturing double-sided disk shaped articles for storing data

Abstract

A mold and a process for use in producing data storage articles such as single substrate double-sided disks. In one configuration, a mold for manufacturing a substrate includes a stamper, at least one holder having an interface with the stamper, and a vacuum line for applying a retention force to maintain the interface between the holder and the stamper. In another configuration, the mold includes a demolding line for applying a demolding force to the substrate to aid in separating the substrate from the stamper. The various embodiments of the present invention provide, among other things, easier and faster stamper changeover, substrates and final data storage articles having improved process indicia such as thickness, flatness, inner and outer diameter, and concentricity, and facilitates production of single-substrate double-sided disks.

What is claimed is:  
     
         1 . A single-substrate double-sided disk for storing data comprising: 
 a molded substrate having: 
 a first surface; and  
 a second surface;  
   a first coating on the first surface; and    a second coating on the second surface.    
     
     
         2 . The disk of  claim 1  wherein the first coating and second coating comprise a recording layer.  
     
     
         3 . The disk of  claim 2  wherein the recording layer comprises a magneto-optic recording material.  
     
     
         4 . The disk of  claim 1  wherein the substrate comprises a material selected from the group consisting of thermoset, thermoplastic, glass, and metal.  
     
     
         5 . The disk of  claim 1  wherein the substrate comprises polycarbonate material.  
     
     
         6 . A single-substrate double-sided disk comprising: 
 a molded substrate having: 
 a first side having a surface profile;  
 a second side having a surface profile; and  
   a recording layer included on the first side and on the second side.    
     
     
         7 . The disk of  claim 6  wherein the recording layer comprises a magneto-optic recording material.  
     
     
         8 . The disk of  claim 6  further comprising a reflective layer, a first dielectric layer, and a second dielectric layer wherein the first and second dielectric layers are disposed adjacent opposite sides of the recording layer.  
     
     
         9 . The disk of  claim 6  wherein the substrate comprises a material selected from the group consisting of thermoset, thermoplastic, glass, and metal.  
     
     
         10 . The disk of  claim 6  wherein the substrate comprises polycarbonate material.  
     
     
         11 . The disk of  claim 6  wherein the substrate is formed in a mold having a first stamper and a second stamper by a process including 
 applying a retention force through a vacuum line to at least one holder to maintain an interface between the holder and at least one of the first stamper and second stamper within the mold such that the interface acts as a barrier preventing mold resin from entering the vacuum line during the mold process;  
 imparting the first surface profile on the substrate with the first stamper; and  
 imparting the second surface profile on the substrate with the second stamper.  
 
     
     
         12 . The disk of  claim 11  wherein the process also includes application of a demolding force through a demolding line to aid in separation of the substrate from the stamper.  
     
     
         13 . A method of manufacturing substrates, comprising: 
 applying a retention force through a vacuum line to at least one holder to maintain an interface between the holder and a stamper within a mold; and    molding a substrate.    
     
     
         14 . The method of  claim 13  further comprising applying a demolding force through a demolding line to the substrate to aid in separating the substrate from the stamper.  
     
     
         15 . The method of  claim 13  used to manufacture substrates for single-substrate single-sided disks having improved process indicia.  
     
     
         16 . The method of  claim 13  used to manufacture substrates for single-substrate double-sided disks.  
     
     
         17 . A method of making an air-incident, magneto-optic single-substrate double-sided disk comprising: 
 forming a substrate in a mold having a first stamper and a second stamper by applying a retention force through a vacuum line to at least one holder to maintain an interface between the holder and at least one of the first stamper and second stamper such that the holder acts as a barrier to prevent flow of resin into the vacuum line during the mold process; and    forming a recording layer over the substrate.    
     
     
         18 . The method of  claim 10  wherein forming a substrate in a mold further comprises applying a demolding force through a demolding line to the substrate to aid in separating the substrate from the stamper.  
     
     
         19 . A method of making an air-incident, magneto-optic single-substrate double-sided disk comprising: 
 forming a substrate in a mold having a first stamper and a second stamper by applying a retention force through a vacuum line to at least one holder to maintain an interface between the holder and at least one of the first stamper and second stamper such that the holder acts as a barrier to prevent flow of resin into the vacuum line during the mold process;    forming a reflective layer over the substrate;    forming a first dielectric layer over the reflective layer;    forming a recording layer over the first dielectric layer; and    forming a second dielectric layer over the recording layer.    
     
     
         20 . The method of  claim 19  wherein forming a substrate in a mold further comprises applying a demolding force through a demolding line to the substrate to aid in separating the substrate from the stamper.  
     
     
         21 . A method of changing a stamper in a mold comprising: 
 releasing the stamper from the mold by reducing a retention force and supplying a positive force through a vacuum line to a holder having an interface with the stamper;    replacing the stamper with a second stamper; and    applying a retention force through the vacuum line to maintain an interface between the holder and the second stamper.