Abstract

A catalytic distillation process, which when operated under vacuum conditions, makes possible the facilitation of peroxyacid chemistry under intrinsically safe conditions with superior efficiency compared to conventional technology. In particular, the process can be used for the production of performic acid (PFA) created from the chemical reaction of formic acid and hydrogen peroxide, while contacting one or more kinds of heterogeneous catalysts, immobilized in one or more regions of the reactor (i.e. within reaction zones within the column). Aqueous hydrogen peroxide and formic acid feed streams are directed to the catalytic distillation column. The products are separated from the reactants in situ from the distillation action within the column The process is made efficient by utilizing moisture tolerant catalyst materials which facilitate the chemical conversion of the reactants operating at or near stoichiometric amount and by operating the catalytic distillation reactor at or near 100% conversion and at an optimal reflux ratio which prevents the accumulation of water in the system while maximizing external mass transfer rates, catalyst wetting efficiency and energy efficiency.

IPC Classes  ?

• C07C 407/00 - Preparation of peroxy compounds
• B01D 3/00 - Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
• C07C 409/24 - Peroxy compounds the —O—O— group being bound between a C=O group and hydrogen, i.e. peroxy acids

Abstract

A thick film high temperature thermoplastic insulated resistive heating element including one or more base dielectric layers screen printed on a metal substrate having a composition one or more melt-flowable thermoplastic polymers, inorganic filler particles, a transition dielectric layer on top of the uppermost based dielectric layer containing inorganic additives in addition to one or more melt-flowable thermoplastic polymers and inorganic filler particles. A heater layer is coated on top of the top dielectric layer where the topmost dielectric layer acts as a transition layer between the uppermost dielectric to protect the adjacent resistor layer from the development of hot spots and cracking arising from the propagation of microcracks due to, amongst other things, residual stresses transmitted to the resistive layer from the sub-layers due to the thermal history of the resistive heater and substrate. The topmost transition dielectric layer is comprised of a ternary or higher mixture of the thermoplastic material such as, but not limited to, polyether ether ketone (PEEK), the inorganic filler such as alumina and other additives such as aluminum nitride.

IPC Classes  ?

• H05B 3/20 - Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater
• B41F 15/00 - Screen printers
• H05B 3/10 - Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor

Abstract

A method for producing a thermoplastic film-substrate resistive thick film heating element is described, involving the melt bonding of an electrically insulating, optionally filled high temperature thermoplastic film to a substrate. This thick film heating element includes an optionally filled high temperature thermoplastic film-substrate onto which is deposited at least a resistive thick film, and is capable of operating over a wide range of power densities for consumer and industrial heating element applications.

IPC Classes  ?

• H05B 3/26 - Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater non-flexible heating conductor mounted on insulating base
• B32B 37/04 - Methods or apparatus for laminating, e.g. by curing or by ultrasonic bonding characterised by the partial melting of at least one layer

Goods & Services

Heating elements for use as a component by other manufacturers of finished appliances

Goods & Services

Heating elements for use as a component by other manufacturers of finished appliances

Abstract

The present invention provides an integrated thick film heating element on a substrate made from high temperature melt-flowable thermoplastic polymer/powder additive formulations which form an electrically insulating thermoplastic dielectric coating on the substrate, and electrically resistive lead free films and electrically conductive film formulations that are deposited and fired to form an integrated thick film heating element on a substrate at a processing temperature well below 600°C. This thick film heating element is formed on a substrate material coated first with the electrically insulating, filled melt flowable high temperature thermoplastic polymer/powder composite layer on which is deposited the electrically resistive lead free thick film that is capable of operating over a wide range of power densities for consumer and industrial heating element applications, with suitable electrical insulation properties under temperature cycling to for example 250°C.

IPC Classes  ?

• H05B 3/10 - Heating elements characterised by the composition or nature of the materials or by the arrangement of the conductor
• C08L 71/10 - Polyethers derived from hydroxy compounds or from their metallic derivatives from phenols
• C08L 79/08 - PolyimidesPolyester-imidesPolyamide-imidesPolyamide acids or similar polyimide precursors
• C09D 5/25 - Electrically-insulating paints or lacquers
• H05B 3/20 - Heating elements having extended surface area substantially in a two-dimensional plane, e.g. plate-heater