Ceramic-based humidity sensitive material with liquid polymeric delivery vehicle

A method of producing a humidity sensing material, comprising:

• providing particles of barium oxide, titanium dioxide and lanthanum hydroxide, wherein all of said particles have an average grain diameter in a range of 20-120 nm;
• mixing 60-70 weight percent of said particles of barium oxide, 30-40 weight percent of said particles of titanium dioxide and 0.2-5.0% weight percent of said particles of lanthanum hydroxide so as to form a mixture of particles;
• heating the mixture of particles at a temperature in a range of 1150-1350° C. in a nitrogen atmosphere for a first predetermined amount of time so as to form a sintered mixture;
• cooling the sintered mixture in the nitrogen atmosphere;
• milling the sintered mixture to produce milled particles having diameters within a range of 50-700 nm;
• mixing 95-99 weight percent of said milled particles and 1.0-5.0 weight percent of an alkali hydroxide selected from the group consisting of potassium hydroxide, sodium hydroxide, rubidium hydroxide and lithium hydroxide to form a composite dielectric material;
• milling the composite dielectric material to produce a composite dielectric powder;
• heating the composite dielectric powder in a nitrogen atmosphere at a temperature less than or equal to 850° C.;
• cooling the composite dielectric powder in the nitrogen atmosphere;
• thereafter mixing 70-80 weight percent of said composite dielectric powder and 20-30 weight percent of a liquid epoxy binder to produce a homogenous liquid mixture;
• depositing a layer of the homogeneous liquid mixture onto a substrate;
• and
• processing the substrate and said layer to remove liquid portions of the homogeneous liquid mixture.

A method of manufacturing a humidity sensor, the method comprising:

• providing particles of barium oxide, titanium dioxide and lanthanum hydroxide, wherein all of said particles have an average grain diameter in a range of 20-120 nanometers;
• mixing 60-70 weight percent of said particles of barium oxide, 30-40 weight percent of said particles of titanium dioxide and 0.2-5.0% weight percent of said particles of lanthanum hydroxide so as to form a mixture of particles;
• heating the mixture of particles in a nitrogen atmosphere at a first predetermined temperature for a first predetermined amount of time so as to form a sintered mixture;
• cooling the sintered mixture in the nitrogen atmosphere;
• milling the sintered mixture to produce milled particles having diameters within a range of 50-700 nanometers;
• mixing 95-99 weight percent of said milled particles and 1.0-5.0 weight percent of an alkali hydroxide so as to form a composite dielectric material;
• milling the composite dielectric material to form a composite dielectric powder;
• heating the composite dielectric powder in a nitrogen atmosphere at a second predetermined temperature for a second predetermined amount of time;
• cooling the composite dielectric powder in the nitrogen atmosphere;
• mixing 70-80 weight percent of said composite dielectric powder and 20-30 weight percent of a liquid polymeric binder to form a homogenous liquid mixture;
• providing a first electrode;
• printing a layer of said homogeneous liquid mixture onto said first electrode;
• processing said first electrode with said layer thereon to remove liquid portions of said homogeneous liquid mixture;
• and
• providing a second electrode on said layer after said liquid portions of said liquid mixture have been removed.

A method of manufacturing a humidity sensor, the method comprising:

• providing a substrate having a first electrode and a second electrode, wherein the first electrode and the second electrode are separated by an electrode gap;
• providing particles of barium oxide, titanium dioxide and particles of lanthanum hydroxide, wherein all of said particles have an average grain diameter in a range of 20-120 nanometers;
• mixing 60-70 weight percent of said particles of barium oxide, 30-40 weight percent of said particles of titanium dioxide and 0.2-5.0% weight percent of said particles of lanthanum hydroxide so as to form a mixture of particles;
• heating the mixture of particles in a nitrogen atmosphere at a first predetermined temperature for a first predetermined amount of time so as to produce a sintered mixture;
• cooling the sintered mixture in the nitrogen atmosphere;
• milling the sintered mixture to produce milled particles having diameters within a range of 50-700 nanometers;
• mixing 95-99 weight percent of said milled particles and 1.0-5.0 weight percent of an alkali hydroxide to provide a composite dielectric material;
• milling the composite dielectric material to form a composite dielectric powder;
• heating the composite dielectric powder in a nitrogen atmosphere at a second predetermined temperature for a second predetermined amount of time;
• cooling the composite dielectric powder in the nitrogen atmosphere;
• mixing 70-80 weight percent of said composite dielectric powder and 20-30 weight percent of a liquid polymeric binder to form a homogenous liquid mixture;
• printing a layer of said homogeneous liquid mixture onto said substrate so as to fill the electrode gap and cover portions of the said first electrode and said second electrode;
• and
• processing said substrate with said layer thereon to remove liquid portions of said homogeneous liquid mixture.