Moisture indicating molding resins
AssigneeE. I. Du Pont de Nemours and Company
InventorArthur Z. Moss
Life of this patent
Estimating the term…
Abstract
Melt formable thermoplastic resins which exhibit a difference in color between their wet and dry states, processes for melt forming such resins, and the resulting melt formed shaped articles are provided.
Claims23
A resin composition comprising
- 1) discrete particles of a moisture indicator composition comprising one or more thermoplastic resins, suitable for melt forming shaped articles, containing a moisture indicator, and
- 2) discrete particles of the same or one or more distinct plain thermoplastic resins,
- wherein the relative thickness of the moisture indicator composition particles and the resin particles are such that a visual color change occurs in the moisture indicator composition particles at or below the critical water concentration of the resin composition.
A moisture indicating composition comprising one or more thermoplastic resins, suitable for melt forming shaped articles, containing a moisture indicator, which composition is in the form of discrete particles and exhibits a color change between the wet and dry states of the composition at or below the critical water concentration of the resin.
A resin composition comprising
- 1) discrete particles of a moisture indicator composition comprising nylon-6, 6 containing CoCl.sub.2, and
- 2) discrete particles of plain nylon-6,6,
- wherein the relative cross section of the moisture indicator composition particles and the nylon-6,6 particles are such that a color change occurs in the moisture indicator composition at or below the critical water concentration of the resin composition.
A method of using a resin composition to form shaped articles comprising
- 1) melting a resin composition comprising a) discrete particles of a moisture indicator composition of one or more thermoplastic resins, suitable for melt forming shaped articles, containing a moisture indicator, and b) discrete particles of the same or one or more distinct plain thermoplastic resins,
- wherein the relative thickness of the moisture indicator composition particles and the resin particles are such that a visual color change occurs in the moisture indicator composition particles at or below the critical water concentration of the resin composition,
- 2) shaping the resulting melt or liquid, and
- 3) cooling the melt or liquid to solidify the composition into a shaped article.
A method of using a moisture indicating composition to form shaped articles comprising
- 1) melting a moisture indicating composition comprising particles of one or more thermoplastic resins, suitable for melt forming shaped articles, containing a moisture indicator, which composition exhibits a color change between its wet and dry states at or below the critical water concentration of the resin,
- 2) shaping the resulting melt or liquid, and
- 3) cooling the melt or liquid to solidify the composition into a shaped article.
A method for monitoring the water content of a resin composition prior to melt forming processing, said resin composition comprising
- 1) discrete particles of a moisture indicator composition comprising one or more thermoplastic resins suitable for melt forming shaped articles containing a moisture indicator, and
- 2) discrete particles of the same or one or more distinct plain thermoplastic resins,
- wherein the relative thickness of the moisture indicator composition particles and the resin particles are such that a visual color change occurs in the moisture indicator composition particles at or below the critical water concentration of the resin composition, said method comprising visually inspecting the color of moisture indicator composition particles in the resin composition, and comparing the color to the colors of the wet and dry states of the moisture indicator composition.
A method for monitoring the water content of a moisture indicator composition prior to melt forming processing said moisture indicating composition comprising one or more thermoplastic resins suitable for melt forming shaped articles containing a moisture indicator, which composition is in the form of discrete particles and exhibits a color change between the wet and dry states of the composition at or below the critical water concentration of the resin, said method comprising visually inspecting the color of the moisture indicator composition, and comparing the color to the colors of the wet and dry states of the moisture indicator composition.
Dependencies are inferred from the claim text.