Novel mineral composition

Abstract

A mineral composition that contains at least about 90 weight percent of headlap granules, at least about 50 weight percent of calcium carbonate, and from about 0.1 to about 1.0 weight percent of a pigmented material. The pigmented material contains from about 10 to about 35 weight percent of pigment and from about 90 to about 65 weight percent of a resin. The mineral composition has superior adhesion properties; when it is tested in accordance with ASTM Standard Test D 4977-03, it loses less than 5 grams of material.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATION [0001] This patent application is a continuation-in-part of applicant's copending patent application Ser. No. 11 / 266,833, filed on Nov. 4, 2005.FIELD OF THE INVENTION [0002] A mineral composition comprised of at least 50 weight percent of calcium carbonate and from about 0.1 to about 1 weight percent of a pigmented material; the composition has superior granule adhesion properties as measured by ASTM Standard Test D 4977-03. BACKGROUND OF THE INVENTION [0003] Roofing shingles are comprised of a headlap portion and a butt portion; granules are often used in the headlap portion. Reference may be had, e.g., to U.S. Pat. No. 3,921,358 (a composite asphalt-impregnated felt roofing shingle comprising a rectangular sheet having a headlap portion and a butt portion), 4,717,614 (a shingle whose headlap portion is coated with a layer of asphaltic material), 4,900,589 (a process for applying granules to a moving sheet having a headlap area and a bu...

AI Technical Summary

Benefits of technology

[0014] In accordance with this invention, and in one embodiment thereof, there is provided a mineral composition comprised of at least about 90 weight percent of headlap granules, at least about 50 weight percent of calcium carbonate, from about 0.1 to about 1.0 weight percent of a pigmented material, less than about 100 parts per million of a metal

Problems solved by technology

Granules made from such coal slag often contain substantial amounts of toxic metals, such as, e.g., arsenic, barium, cadmium, chromium, lead, mercury, selenium, and silver.

However, at levels exceeding these requirements, both essential and non-essential metals can disturb metabolism by binding non-specifically to biomolecules and by inflicting oxidative damage due to their ability to catalyse redox reactions.

This can result in the deactivation of essential enzymatic reactions, damage to cellular structures (especially membranes), and DNA modification (mutagenesis).

In humans, exposure to high levels of metals can cause acute toxicity symptoms, while long-term exposure to lower levels can trigger allergies and even cancers.

Images