Edible holographic products, particularly pharmaceuticals and methods and apparatus for producing same

Abstract

An edible product such as a unit dosage form of a pharmaceutically active substance includes a layer of a material that can receive and retain a high resolution microrelief that can convey information. The microrelief is themo-formable, preferably formed from an aqueous solution of HPMC and/or HPC plus a plasticizer and colorant. Other additives such as strengtheners, surfactants and adherents may be used depending on the application. The materials are selected and proportioned to control the fading or change in color of the visual image or effect produced by the relief to indicate exposure to an unacceptable degree of heat or humidity. The dosage form can be the relief-containing layer itself with the pharmaceutical carried therein. In a preferred form, the layer is an outer coating over a core containing the pharmaceutically active substance. Coated tablets are configured to resist twinning. To produce such dosage forms, the coated core is transported in unison with a flexible mold or transfer plate that can heat-replicate the microrelief on the outer layer of the dosage form, followed by a cooling and release of the transfer plate from the coating.

1 - 28 . (canceled)  
   
   
       29 . A method of producing a microrelief on an ingestible dosage form having a core which can contain a pharmaceutically active substance and a pharmaceutically acceptable carrier, comprising the steps of: 
 a. coating said core with a layer of a thermo-formable material that can receive and retain a holographic diffraction pattern;    b. providing a plate having a holographic diffraction pattern formed on at least a portion of a first surface thereof;    c. heating at least one of said plate and said coating during or prior to the time when they are in said opposed relationship;    d. pressing said first surface into said coating to replicate said holographic diffraction pattern in said coating;    e. cooling said coating thus replicated; and    f. demolding said first plate surface from said coating.    
   
   
       30 . The holographic dosage form production method of  claim 29  wherein said coating is pan coating and further comprising the step of controlling twinning of said coated tablets.  
   
   
       31 . The holographic dosage form production method of  claim 30  wherein said twinning control comprises forming said core with at least one curved face that receives said coating and said pressing.  
   
   
       32 . The holographic dosage form production method of  claim 31  wherein said curvature is sufficient to resist twinning, but not sufficient to distort the holographic image pressed into in said coating.  
   
   
       33 . The holographic dosage form production method of  claim 32  wherein said core face is generally circular and, measured as an angle in a plane through the face, the curvature is in the range of about 0.6 radian to about 0.9 radian.  
   
   
       34 . The holographic dosage form production method of  claim 30  wherever said twinning control comprises forming said core with a recess within at least one face of said coat, said recess having a generally flat bottom that receives said coating layer.  
   
   
       35 . The holographic dosage form production method of  claim 34  wherein said recess is sufficiently shallow that said pressing transfers said holographic pattern reliably.  
   
   
       36 . The holographic dosage form production method of  claim 42  wherein said recess is less than about 0.01 mm.  
   
   
       37 . The diffractive dosage form production method of  claim 29  wherein said coating includes said thermo-formable material bonding reliably with said core.  
   
   
       38 . The holographic dosage form production method of  claim 29  or  37  wherein said thermo-formable material selected from the group consisting of: gelatin, hydroxypropylmethylcellulose (HPMC), hydroxyproplycellulose (HPC), modified food starches, waxes, vegetable gums and combinations thereof.  
   
   
       39 . The holographic dosage form production methods of  claim 38  wherein said material includes solids of a modified cellulose, a plasticizer, and a colorant.  
   
   
       40 . The holographic dosage form production method of  claim 38  wherein said coating produces a layer in the range of 0.25% to 7.25% of the weight of said dosage form.  
   
   
       41 . The holographic dosage form production method of  claim 29  further comprising transporting said coated cores to a position opposite said first surface, and wherein said plate providing comprises continuously advancing a belt of a semi-flexible material containing said pattern on at least one surface thereof in coordinating with said transporting of said coated dosage forms.  
   
   
       42 . The holographic dosage form production method of  claim 41  wherein said semi-flexible material is selected from the group consisting of: a thin sheet metal, rubber, a laminate of thin sheet metal and a layer of a resilient backing material opposite said first surface, and a rubber and metal composite.  
   
   
       43 . The holographic dosage form production method of  claim 42  wherein said thin sheet metal is a nickel composite with a thickness of 1 mils to 5 mils, and said holographic diffraction pattern is electroformed on said first surface.  
   
   
       44 . The holographic dosage form production method of  claim 41  wherein said transporting also aligns said coated cores.  
   
   
       45 . The holographic dosage form production method of claims  41  or  43  wherein said coated core facing said plate during said pressing is non-planar, and said belt flexibility is sufficient to allow said belt to conform to said non-planar coating desiring said pressing.  
   
   
       46 . The holographic dosage form production method of  claim 41  wherein said transporting comprises conveying of a linear array of said coated cores in a parallel, closely spaced relationship with a portion of said belt, and moving said belt in coordination with said conveying.  
   
   
       47 . The holographic dosage form production method of  claim 46  wherein said heating is a rapid, localized heating of said belt during said pressing.  
   
   
       48 . The holographic dosage form production method of  claim 47  wherein said heating raises the temperature of said diffraction pattern on said belt to a temperature in the range of 90-150 C.  
   
   
       49 . The holographic dosage form production method of  claim 47  wherein said pressing comprises a brief deflection of said heated belt that places said diffraction pattern in said coating to create said replication of said diffraction pattern in said coating.  
   
   
       50 . The holographic dosage form production method of claims  29  and  47  wherein said pressing occurs for about 0.3 to 3.0 second.  
   
   
       51 . The holographic dosage form production method of  claim 46  wherein said cooling is a rapid, localized cooling that begins immediately after said pressing has formed said diffraction pattern in said coating.  
   
   
       52 . The holographic dosage form production method of  claim 51  wherein said demolding comprises a resumption of said mutually spaced relationship between said coating as said coated and said belt as they continue to move in coordination, after said cooling has begun.  
   
   
       53 - 62 . (canceled)  
   
   
       63 . A method of producing a microrelief on an ingestible dosage form which can contain a pharmaceutically active substance and a pharmaceutically acceptable carrier, comprising the steps of: 
 a. providing a layer of material forming at least a part of the dosage form having a first surface, said material being thermoformable to receive, and once formed, retain, a holographic diffraction pattern on said first surface;    b. providing a holographic diffraction pattern;    c. replicating said holographic diffraction pattern to said first surface by thermoforming said pattern onto said first surface; and    d. rapidly cooling said thermoformed holographic diffraction pattern thus replicated.    
   
   
       64 . The method of  claim 63 , wherein providing a holographic diffraction pattern comprises producing an interference pattern using laser light.  
   
   
       65 . The method of  claim 64 , wherein said laser light is constituted by two laser light beams split from a single laser light source.  
   
   
       66 . The method of  claim 63 , wherein said active substance and carrier are contained in a core and said layer overlies said core.  
   
   
       67 . A method of producing an optical pattern on a surface of an edible article, where the optical pattern interacts with incident light to produce a visible image or effect, comprising the steps of:  
   
   
       67 . A method of producing an optical pattern on a surface of an edible article, where the optical pattern interacts with incident light to produce a visible image or effect, comprising the steps of: 
 providing a laser;    causing said laser to emit first and second beams of light; and    causing said first and second beams of light to interfere to produce an interference pattern on the surface of the edible article, and wherein the interference pattern produces the optical pattern on the surface of the edible article.    
   
   
       68 . The method of  claim 67 , wherein said interference pattern is comprised of light intensity maxima and minima.  
   
   
       69 . The method of  claim 67 , wherein the optical pattern is comprised of a plurality of grooves produced by lines of maximum light intensity in said interference pattern, and a plurality of ridges produced by lines of minimum light intensity in said interference pattern.  
   
   
       70 . The method of  claim 68 , wherein the optical pattern is a microrelief.