Abstract: The present invention is directed to lithographic printing plates that are suitable for imaging by laser discharge using laser ablation. The lithographic printing plates according to the present invention comprise a vacuum deposited polymeric layer comprising polyvinylpyrrolidone having a thickness of up to about 6000 Angstroms, an absorbing layer underlying the first layer that absorbs infrared radiation and has a thickness in a range between about 100 and about 500 Angstroms, and a substrate underlying the absorbing layer. The polymeric layer and the substrate exhibit different affinities for at least one printing liquid selected from the group consisting of ink and an adhesive fluid for ink.

Abstract: A rigid and brittle bright metal flake is formed of a central layer of a reflective material supported on both sides by dielectric layers. In a preferred embodiment, the metal layer is aluminum having a thickness of about 100 nm and the dielectrics are either silicon dioxide or magnesium fluoride, each having a thickness of about 100 nm. The result is a very thin three-layered metal flake about 300 nm thick that exhibits a uniaxial compressive strength of about 8 times a corresponding uniaxial tensile strength. As a result, the metal flake is then afforded the benefits of rigidity and brittle fracture during the manufacturing and applicational processes which ultimately provides favorable planar and specular reflectance characteristics in the visible wavelength range.

Abstract: An optical article comprising a flexible plastic substrate having an index of refraction ranging from 1.55 to 1.71 and having first and second surfaces and an anti-reflection coating carried by the first surface. The anti-reflection coating consists of a high index material and a low index material in which the high index material has an index of refraction of 2.0 and greater to provide the index of refraction difference between the substrate and the high index material of 0.29 to 0.75. The low index material is formed of a material having an index of refraction of 1.38 or less to provide an index of refraction difference between the high index material to the low index material ranging from approximately 0.59 to 0.92.

Abstract: A package or wrapping comprised of a material in the form of a liquid or a solid which is sensitive to water and oxygen. A coated barrier film is sealed about the material and forms a sealed enclosure about the material and serves to protect the material from water vapor and oxygen. The coated barrier film has low oxygen and water permeability and comprises a flexible substantially transparent plastic substrate with first and second surfaces and a thickness ranging from 1 to 7 mils. A substantially colorless barrier coating is formed on at least one of the surfaces and consists solely of graphite free of hydrogen and has a thickness ranging from 50.ANG. to 300.ANG.. The barrier film has a reduced water transmission rate and a reduced oxygen transmission rate with respect to the uncoated substrate and has a visible transparency of 30% or greater.

Abstract: Barrier film with a high colorless transparency comprising a flexible plastic substrate. A barrier layer is formed on the surface and has a thickness ranging from approximately 50 to 100 Angstroms and is formed of a material selected from the group of aluminum oxide, tin oxide and yttrium oxide. An additional barrier layer formed of silicon dioxide may also be formed on the barrier layer.

Abstract: A lithographic laser imageable thin film structure comprising a substrate having first and second surfaces. A vacuum-deposited metal layer is carried by the first surface of the substrate. A layer of semiconductor material is adhered to and overlies the metal layer. The metal layer and the semiconductor material have thicknesses which are selected to maximize absorption of laser energy impinging on the same.

Abstract: Flexible optical medium comprising a flexible substrate having a surface. An imaging layer is carried by the surface and a protective overcoat of silicon dioxide is provided on the imaging layer to provide abrasion resistance for said imaging layer.

Abstract: An optically variable article comprising of a substrate and at least one non-overlapping pair of optically variable structures on the surface of the substrate, the optically variable structures having the same color at one angle of incidence and different colors at all other angles of incidence. The optically variable structures are formed from optically variable pigments, optically variable opaque foils, or optically variable multilayer thin film interference stacks.

Abstract: A laser imageable tuned optical cavity thin film for use with a laser producing laser radiation at a laser wavelength comprising a flexible sheet of plastic having first and second surfaces serving as a film substrate. A thin film stack is disposed on the first surface of the film substrate and comprises a first vacuum-deposited metal layer carried by the first surface. It is also comprised of a dielectric layer deposited on the first metal layer. A second semi-opaque metal layer is vacuum deposited onto the dielectric layer. The thin film stack is tuned to provide maximum absorption at the laser wavelength.

Abstract: An article with a surface with a paint film adherent thereto having a liquid medium hardened into a solid to form said paint film and having first and second parallel surfaces with the first parallel surface being adhered to the surface of the article and the second surface exposed to be viewed by the human eye. A plurality of flakes are provided having first and second planar parallel surfaces lying in said paint film with the first and second planar parallel surfaces being parallel to the first and second parallel surfaces of the paint film. The flakes are characterized in that they have physical dimensions such that when the dimensions of the flakes are measured parallel to and perpendicular to the respective first and second planar parallel surfaces, an aspect ratio of at least two-to-one is provided.

Abstract: An article for applying a color shifting optically variable coating on a substrate formed from a polymeric web, a release coating on the web and an optically variable coating wherein the optically variable coating consists of a semi-opaque metal layer adjacent to the release layer, a transparent dielectric layer on the semi-opaque metal layer and a reflective metal layer on the dielectric layer. The article can be bonded to a substrate by means of hot stamping with the hot stamp adhesive layer being applied to the article or applied to the substrate.

Abstract: A viewing device for use by an observer to ascertain the authenticity of an instrument of value having an image formed from an optically variable device. The viewing device includes a frame structure which permits viewing of the image in a fixed spatial orientation and a reflector carried by the frame structure for permitting the observer to see simultaneously the image in first and second colors without movement of the observer, the viewing device or the image.

Abstract: A method of heat-treating multilayer interference platelets to improve the durability of the platelets comprising subjecting the platelets at a temperature of 200.degree.-300.degree. C. for 10 minutes to 24 hours. The platelets are formed from a multilayer interference thin film construction comprising a metal reflecting layer having a multilayer interference thin film structure on both sides of the metal reflecting layer wherein the multilayer interference thin film structure comprises a pair of layers consisting of a dielectric layer and a semi-opaque metal layer with the dielectric layer of the pair being directly adjacent to the metal reflecting layer.

Abstract: A color-shifting paint comprising a polymeric paint medium and a plurality of colored interference thin film platelets dispersed in the paint medium. Each platelet being characterized in that platelets has first and second generally planar outer surfaces and an edge thickness perpendicular to the first and second generally planar outer surfaces. Each platelet is comprised of a metal reflecting layer having first and second surfaces. A multilayer interference structure is disposed on each of the first and second surfaces of the metal reflecting layer to provide a symmetrical platelet. The multilayer interference thin film structure comprises a pair of layer consisting of a dielectric layer formed of a dielectric material and a semi-opaque layer. with the dielectric layer directly adjacent to the metal reflecting layer. The thickness of the dielectric layer determines the color and the dielectric material determines the degree of color shift.

Abstract: A collection of color-shifting interference thin film platelets of high chroma characterized in that the platelets are comprised of a metal reflecting layer having first and second surfaces and a multilayer interference thin film structure disposed on both surfaces of the metal reflecting layer. The multilayer interference thin film structure comprises a pair of layers consisting of a dielectric layer and a semi-opaque metal layer with the dielectric layer being directly adjacent to a surface of the metal reflecting layer. The layers of the multilayer interference thin film structure lie in parallel planes. Each platelet has an aspect ratio of at least 2:1, respectively, for surfaces parallel to the planes of layers and surfaces perpendicular to the planes of the layers. The platelets have a maximum dimension on any surface ranging from approximately 2-200 microns.

Abstract: A barrier film comprising a flexible substantially of transparent substrate having first and second surfaces. A substantially colorless barrier coating is formed on at least one of said surfaces of a graphite material having a thickness ranging from 50 to 350 .ANG..

Abstract: A polymeric sheet comprising a layer of polymeric material having a first and second parallel surfaces. A plurality of oriented multilayer interference thin film flakes are disposed in the layer of polymeric material. The flakes have first and second parallel surfaces and a width and a thickness and have an aspect ratio of at least 2:1 for the width with respect to the thickness.

Abstract: Articles and methods for forming optically variable thin film flakes and replicated coatings having preselected optical properties. The articles generally comprise a flexible web of material and an optically variable thin film coating formed on one surface of the web. The optically variable coating is separated from the web to form optically variable thin film flakes. The flakes are disposed in ink and paint vehicles to provide optically variable inks, paints and the like.

Abstract: Method for providing a patterned thin film on a flexible web-like substrate having at least one surface. A patterned release coating which carries the desired pattern is deposited on the surface and has openings therein through which the surface of the substrate is exposed. A thin film is deposited over the patterned release coat and onto the portions of the surface exposed through the openings. The patterned release coating is then removed and the thin film portions carried thereby to provide a patterned thin film on the substrate.

Abstract: Articles and methods for forming optically variable thin film flakes and replicated coatings having preselected optical properties. The articles generally comprise a flexible web of material and an optically variable thin film coating formed on one surface of the web. The optically variable coating is separated from the web to form optically variable thin film flakes. The flakes are disposed in ink and paint vehicles to provide optically variable inks, paints and the like.