Texas Instruments Corporation

Mlc Technologies, Inc.

David C Hill

Bernard M Kulwicki

George Trenkler

Richard A Hildebrandt

An artist's palette is shown having surface roughness values conducive to wetting, spreading and suspension maintenance of water color, acrylic and other pigment media. Porous materials having selected permeability versus open porosity are disclosed which are useful both as in a palette substrate as well as a color pot in a reservoir system module that provides extended pigment suspension life. Interchangeable color pots receivable in modules which in turn are receivable in work boxes are disclosed providing optimum artist flexibility.

Apparatus for maintaining optimum artist's pigment media characteristics

A body of ceramic material of positive temperature coefficient of resistivity is molded so that a plurality of passages extend between opposite ends of the body. In molding the body, lands or abutments of resistor material are formed around the ends of alternate body passages at one end of the body and around the ends of the other passages at the opposite end of the body. A band of masking material is applied to the sides of the body and the body is then immersed in a coating bath for simultaneously coating the inner walls of the body passages, the ends of the body, and the unmasked bands of the body side surface with an electrically conductive ohmic contact material. Preferably, the ohmic contact and masking materials are selected to be impervious to reducing atmospheres and the ends of the body are treated for coating at least the unmasked bands of the body side surfaces with a material characterized by low electrical contact resistance. Thereafter, the outer ends of the abutments are abraded for removing coating materials from the ends of the abutments.

Resistor device

An improved electrical resistor device is made by molding a body of ceramic material of positive temperature coefficient of resistivity so that a plurality of passages extend in a pattern in spaced side-by-side relation to each other between opposite ends of the body. In molding the body, lands or abutments of resistor material are formed around the ends of alternate body passages at one end of the body and similar lands or abutments are formed around the ends of the other passages at the opposite end of the body. A band of masking material is applied to the sides of the body extending around the body leaving the ends of the body, and bands of the body side surface adjacent each end of the body, free of masking material. The masked body is then immersed in a coating bath for simultaneously coating the inner walls of the body passages, the ends of the body, and the unmasked bands of the body side surface with an electrically conductive ohmic contact material. Preferably, the ohmic contact and masking materials are selected to be impervious to reducing atmospheres and the like for protecting masked and coated portions of the ceramic resistor material against degradation in such atmospheres. Preferably, the ends of the body are immersed in an additional coating bath or are otherwise treated for coating at least the unmasked bands of the body side surfaces with a material characterized by low electrical contact resistance. Thereafter, the outer ends of the abutments are abraded for removing coating materials from the ends of the abutments. In this way, ohmic contacts in alternate body passages are connected together at one end of the body to form a first device terminal having low contact resistance while ohmic contacts in the other body passages are connected together at the opposite end of the body to form a second device terminal. Alternatively, the ends of the body abutments are masked prior to immersion of the body in the contact coating baths for permitting omission of the noted abrading step.

Resistor device and method of making

A temperature sensor particularly adapted for use with digital displays or controls comprises an oscillator circuit coupled to a capacitor formed of ferroelectric material in order to provide a linear relation of frequency with temperature. Both chip and multilayer capacitors are shown to be useful as the sensing element.

Growing community of inventors

Attleboro, MA, United States of America

David C Hill