IP Library › Granted Patent US 12,595,180
Granted Patent B2
US 12,595,180 · App. 18/181,820 · Granted Apr 7, 2026

Ultra-white silica-based filler

Inventors: Gregory Kenneth Bedford (Spring, TX); Claud Eric Westbrook, III (Conroe, TX)
Assignee: Covia Holdings LLC
C01B33/12C04B14/06C09J11/04C09K3/10C01P2006/62C01P2006/80C09K2200/0247
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Quick Facts
Patent No.
US 12,595,180
App. No.
18/181,820
Granted
Apr 7, 2026
Kind
B2
Abstract

An ultra-white granular silica-based filler comprises at least 99.5 wt. % silica, wherein the crystal structure of the silica is such that the silica-based filler comprises 40 to 80 wt. % cristobalite, 1 to 25 wt. % tridymite, 2-60 wt. % quartz and <5 wt. % amorphous silica, wherein the temperature of the ultra-white granular silica-based filler is no higher than 50° C. and further wherein the ultra-white granular silica-based filler exhibits an L* value in the CIELAB color space of 95-98. In addition, an ultra-white powder filler is obtained by milling, grinding or comminuting the ultra-white granular silica-based filler. The ultra-white powder filler exhibits an L* value in the CIELAB color space of 95-98.5.

Claims (9)

1 . An engineered stone product comprising:

an ultra-white granular silica-based filler comprising at least 99.5 wt. % silica, wherein the ultra-white granular silica-based filler has a particle size of from about 88 μm to about 210 μm, an L* value of from 97 to 98, and comprises ≤80 wt. % cristobalite, from 20-30 wt. % tridymite, ≤2 wt. % amorphous silica, and from 2-20 wt. % quartz; and

one or more binders.

2 . The engineered stone product according to claim 1 , wherein the product is selected from the group consisting of a countertop and tile.

3 . The engineered stone product according to claim 1 , wherein the ultra-white granular silica-based filler has a density of from about 2.25 g/cc to about 2.35 g/cc.

4 . The engineered stone product according to claim 1 , wherein the ultra-white granular silica-based filler has ≤50 wt. % cristobalite.

5 . An engineered stone product comprising:

a binder component; and

a filler component comprising at least two filler materials, wherein one filler is an ultra-white granular silica-based filler that comprises at least 99.5 wt. % silica, has a particle size of from about 88 μm to about 210 μm, an L* value of from 97 to 98, and comprises ≤80 wt. % cristobalite, from 20-30 wt. % tridymite, ≤2 wt. % amorphous silica, and from 2-20 wt. % quartz.

Assignments (2)
SECURITY INTEREST Recorded Mar 31, 2025
From: COVIA SOLUTIONS LLC; COVIA HOLDINGS LLC
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 070681/0759 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Mar 10, 2023
From: BEDFORD, GREGORY KENNETH; WESTBROOK, CLAUD ERIC
To: COVIA HOLDINGS LLC
Reel/Frame 062944/0907 →
Continuity (3)
Continuation 17005751 · Aug 28, 2020
Provisional Application 62893560 · Aug 29, 2019
Related Publication 20230202849A1 · Jun 29, 2023
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