Abstract:
A high speed process for forming a multi layered thin film structure in a vacuum wherein each film is less than about four microns thick and the total layers can reach upwards to 4,000 or more. The polymeric layers are formed of a cross linked component selected from the group consisting of polyfunctional acrylates and mixtures of polyfunctional acrylates and monocrylates with the component having a preferable molecular weight of between 200 and 300 and a vapor pressure preferably in excess of 1.times.10.sup.-2 Torr. The polymeric layers may be interleaved with metal layers.
Abstract:
A polymer-based optically-variable device for security applications has a high degree of color uniformity over the device area. The uniformity of thickness of the structure used in such devices is optimized by controlling previously neglected process parameters such as the temperature distribution of the deposition nozzle, the substrate and the deposition drum, their emissivities, the micro-roughness of the substrate, and the rate of monomer re-evaporation. Re-evaporation is minimized by initiating radiation-curing within two seconds of monomer deposition. The equipment is carefully monitored to eliminate all sources of emissivity non-homogeneities, such as surface blemishes in the surface areas exposed to the substrate. Substrates with haziness less than 5% and gloss greater than 90% are preferred. As a result, a maximum thickness variation of less than 5% over the transmissive layer of the optically variable device is found to ensure that no appreciable color-shift variation is visible to the naked eye.
Abstract:
A plasma is produced in a treatment space (58) by diffusing a plasma gas at atmospheric pressure and subjecting it to an electric field created by two metallic electrodes (54,56) separated by a dielectric material (64), and a precursor material is introduced into the treatment space to coat a substrate film or web (14) by vapor deposition or atomized spraying at atmospheric pressure. The deposited precursor exposed to an electromagnetic field (AC, DC, or plasma) and then it is cured by electron-beam, infrared-light, visible-light, or ultraviolet-light radiation, as most appropriate for the particular material being deposited. Additional plasma post-treatment may be used to enhance the properties of the resulting coated products.
Abstract:
A porous substrate is pretreated in a plasma field and a functionalizing monomer is immediately flash-evaporated, deposited and cured over the porous substrate in a vacuum vapor-deposition chamber. By judiciously controlling the process so that the resulting polymer coating adheres to the surface of individual fibers in ultra-thin layers (approximately 0.02–3.0 μm) that do not extend across the pores in the material, the porosity of the porous substrate is essentially unaffected while the fibers and the final product acquire the desired functionality. The resulting polymer layer is also used to improve the adherence and durability of metallic and ceramic coatings.
Abstract:
A porous substrate is pretreated in a plasma field and a functionalizing monomer is immediately flash-evaporated, deposited and cured over the porous substrate in a vacuum vapor-deposition chamber. By judiciously controlling the process so that the resulting polymer coating adheres to the surface of individual fibers in ultra-thin layers (approximately 0.02-3.0 μm) that do not extend across the pores in the material, the porosity of the porous substrate is essentially unaffected while the fibers and the final product acquire the desired functionality. The resulting polymer layer is also used to improve the adherence and durability of metallic and ceramic coatings.
Abstract:
A plasma is produced in a treatment space (58) by diffusing a plasma gas at atmospheric pressure and subjecting it to an electric field created by two metallic electrodes (54,56) separated by a dielectric material (64), a precursor material is introduced into the treatment space to coat a substrate film or web (14) by vapor deposition or atomized spraying at atmospheric pressure. The deposited precursor is cured by electron-beam, infrared-light, visible-light, or ultraviolet-light radiation, as most appropriate for the particular material being deposited. Additional plasma post-treatment may be used to enhance the properties of the resulting coated products.
Abstract:
A monomer is selected to produce a polymeric film having desirable characteristics for a particular application. The monomer is ppolymerized under controlled conditions to produce a solid oligomer having those characteristics at a molecular weight suitable for evaporation under vacuum at a temperature lower than its thermal decomposition temperature. The process of polymerization to produce the oligomer is carried out under conditions that yield a finite molecular-chain length with no residual reactive groups. The solid oligomer so produced is extruded as a film onto a revolving drum (38) in the evaporation section (40) of a vapor deposition chamber, and then cryocondensed on a cold substrate (44) to form a solid film having the same characteristic selected in the solid oligomer constituting the starting material. As a result of the initial complete reaction to produce the oligomer, the thin-film product does not contain unreacted groups and all attendant disadvantages are avoided.
Abstract:
A hybrid film, comprising a first polymer film having a plasma-treated surface and a second polymer film having first and second surfaces, with the first surface of the second polymer film being disposed along the first plasma-treated surface of the first polymer film, has superior thermal and mechanical properties that improve performance in a number of applications, including food packaging, thin film metallized and foil capacitors, metal evaporated magnetic tapes, flexible electrical cables, and decorative and optically variable films. One or more metal layers may be deposited on either the plasma-treated surface of the substrate and/or the radiation-cured acrylate polymer. A ceramic layer may be deposited on the radiation-cured acrylate polymer to provide an oxygen and moisture barrier film. The hybrid film is produced using a high speed, vacuum polymer deposition process that is capable of forming thin, uniform, high temperature, cross-linked acrylate polymers on specific thermoplastic or thermoset films. Radiation curing is employed to cross-link the acrylate monomer. The hybrid film can be produced in-line with the metallization or ceramic coating process, in the same vacuum chamber and with minimal additional cost.
Abstract:
A monomer is selected to produce a polymeric film having desirable characteristics for a particular application. The monomer is polymerized under controlled conditions to produce a solid oligomer having those characteristics at a molecular weight suitable for evaporation under vacuum at a temperature lower than its thermal decomposition temperature. The process of polymerization to produce the oligomer is carried out under conditions that yield a finite molecular-chain length with no residual reactive groups. The solid oligomer so produced is liquefied and extruded as a film onto a revolving drum in the evaporation section of a conventional vapor deposition chamber, and it is then cryocondensed on a cold substrate to form a solid thin film having the same desirable characteristic selected in the solid oligomer constituting the starting material. As a result of the initial complete reaction to produce the oligomer, the thin-film product does not contain unreacted groups and all attendant disadvantages are avoided.
Abstract:
A hybrid film, comprising a first polymer film having a plasma-treated surface and a second polymer film having first and second surfaces, with the first surface of the second polymer film being disposed along the first plasma-treated surface of the first polymer film, has superior thermal and mechanical properties that improve performance in a number of applications, including food packaging, thin film metallized and foil capacitors, metal evaporated magnetic tapes, flexible electrical cables, and decorative and optically variable films. One or more metal layers may be deposited on either the plasma-treated surface of the substrate and/or the radiation-cured acrylate polymer. A ceramic layer may be deposited on the radiation-cured acrylate polymer to provide an oxygen and moisture barrier film. The hybrid film is produced using a high speed, vacuum polymer deposition process that is capable of forming thin, uniform, high temperature, cross-linked acrylate polymers on specific thermoplastic or thermoset films. Radiation curing is employed to cross-link the acrylate monomer. The hybrid film can be produced in-line with the metallization or ceramic coating process, in the same vacuum chamber and with minimal additional cost.