Coating composition, granules coated with same, and method of reducing dust generation

• US 5,484,477 A
• Filed: 10/07/1994
• Issued: 01/16/1996
• Est. Priority Date: 03/04/1993
• Status: Expired due to Fees

• Current Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Original Assignee: Minnesota Mining and Manufacturing Co (3M Company)
• Inventors: Penny, Delmon H., George, Billy L., Babirad, Stefan A.
• Primary Examiner(s): BRUNSMAN, DAVID M
• Application Number:
  US08/319,611
• Time in Patent Office: 466 Days
• Field of Search: 428/144, 428/323, 428/329, 428/403, 428/404, 428/407, 428/497, 428/141, 106/239, 106/285, 106/287.35, 106/499, 106/500, 106/506
• US Class Current: 106/499
• CPC Class Codes: B01J 2/006 Coating of the granules without description of the process or the device by which the granules are obtained to prevent the granules sticking together B01J2/30
• CPC Class Codes: C04B 2235/3427 Silicates other than clay, e.g. water glass
• CPC Class Codes: C04B 2235/349 Clays, e.g. bentonites, smectites such as montmorillonite, vermiculites or kaolines, e.g. illite, talc or sepiolite
• CPC Class Codes: C04B 33/04 Clay; Kaolin
• CPC Class Codes: C04B 33/14 Colouring matters
• CPC Class Codes: C04B 35/628 Coating the powders or the macroscopic reinforcing agents
• CPC Class Codes: C08L 2666/02 Organic macromolecular compounds, natural resins, waxes or and bituminous materials
• CPC Class Codes: C08L 2666/74 Aggregates
• CPC Class Codes: C08L 91/00 Compositions of oils, fats or waxes; Compositions of derivatives thereof
• CPC Class Codes: C08L 95/00 Compositions of bituminous materials, e.g. asphalt, tar, pitch
• CPC Class Codes: C09D 201/00 Coating compositions based on unspecified macromolecular compounds
• CPC Class Codes: E04D 7/005 characterised by loose or embedded gravel or granules as an outer protection of the roof covering
• CPC Class Codes: Y10T 428/2438 Coated
• CPC Class Codes: Y10T 428/25 Web or sheet containing structurally defined element or component and including a second component containing structurally defined particles
• CPC Class Codes: Y10T 428/257 Iron oxide or aluminum oxide
• CPC Class Codes: Y10T 428/2991 Coated
• CPC Class Codes: Y10T 428/2993 Silicic or refractory material containing [e.g., tungsten oxide, glass, cement, etc.]
• CPC Class Codes: Y10T 428/2998 including synthetic resin or polymer
• CPC Class Codes: Y10T 428/31844 Of natural gum, rosin, natural oil or lac

Abstract

A coatable composition suitable for reducing dust generation during processing of granular materials consists essentially of a tackifier, an organic oil, and an adhesion agent, the tackifier consisting essentially of an organic material having a glass transition temperature of no less than about 120° C. and a diluent present in sufficient amount to give the tackifier a kinematic viscosity ranging from about 3,000 to about 5,000 centistokes at 100° C. The tackifier is preferably present in the composition at about 0.5 to about 2.0 weight percent of the total weight of the composition, and the adhesion agent is preferably present at about 0.5 to about 5.0 weight percent of the total weight of the composition, with the balance being organic oil. Granular materials having coatings of the composition (with or without the adhesion agent) are presented, as well as methods of reducing dust generation during processing and/or transport of granular materials and methods of making organic oil-coated granular materials.

Claims

1. A coatable composition suitable for reducing dust generation during processing of granular materials, the composition consisting essentially of:

a) an organic oil;

b) an optional adhesion agent; and

c) a tackifier consisting essentially of an organic material having a glass transition temperature of no less than about 120°

C. and a naphthenic oil present in sufficient amount to give the tackifier a kinematic viscosity ranging from about 3,000 to about 5,000 centistokes at 100°

C.;

said organic oil being compatible with the tackifier and the optional adhesion agent.

2. Composition in accordance with claim 1 wherein the tackifier is present in the composition at about 0.5 to about 2.0 weight percent of the total weight of the composition, and the adhesion agent is present in the composition at about 0.5 to about 5.0 weight percent of the total weight of the composition oil.

3. Composition in accordance with claim 1 wherein the tackifier is present at about 0.5 to about 1.0 weight percent of the total weight of the composition.

4. Composition in accordance with claim 1 wherein the organic oil is a mineral oil selected from the group consisting of slate oil, rock oil, coal oil, and seneca oil.

5. Composition in accordance with claim 1 wherein the organic oil is slate oil.

6. Composition in accordance with claim 1 wherein the organic material has a glass transition temperature no less than about 150°

C.

7. Composition in accordance with claim 1 wherein the organic material is selected from the group consisting of polyalkylene resins and polycycloalkene resins.

8. Composition in accordance with claim 7 wherein the polyalkylene resin is selected from the group consisting of polybutene resins, dipentene resins, and terpolymers of ethene, 1-propene, and 1,4-hexadiene.

9. Composition in accordance with claim 8 wherein the polyalkylene resin is the terpolymer of ethene, 1-propene, and 1,4-hexadiene, the diluent is a light-colored naphthenic oil, and the adhesion agent is a silicone oil.

10. Composition in accordance with claim 7 wherein the polycycloalkene resin is selected from the group consisting of phenol-aldehyde resins, terpene resins, rosins, polyethylene rosin esters, phenolic polyterpene resins, limonene resins, and pinene resins.

11. A method of reducing dust generation during processing of granular materials, said granular materials comprising base granules, the method comprising applying to the base granules a coatable composition, wherein the coatable composition consists essentially of:

a) an organic oil;

b) an optional adhesion agent; and

c) a tackifier consisting essentially of an organic material having a glass transition temperature of no less than about 120°

C. and a napthenic oil present in sufficient amount to give the tackifier a kinematic viscosity ranging from about 3,000 to about 5,000 centistokes at 100°

C.;

said organic oil being compatible with the base granules, the tackifier, and the optional adhesion agent.

12. Method in accordance with claim 11 wherein the granular material is heated in a kiln to form kiln-fired granular material and subsequently cooled in a means for cooling to yield cooled granular materials, and the composition is applied to the kiln-fired granular material while the kiln-fired granular material passes through the means for cooling.

13. Method in accordance with claim 12 wherein the composition is also applied to the cooled granular material during transport of the cooled granular material.

14. Method in accordance with claim 11 wherein said composition includes a silicone oil in an amount ranging from about 0.5 to about 5.0 weight percent of the total weight of the coating.

15. A method of making organic oil-coated granular materials comprising the steps of:

a) providing at least one base granule;

b) coating the at least one base granule with a coatable composition in a coating weight ranging from about 0.5 to about 10 grams per kilogram of base granules, wherein the coatable composition consists essentially of;

(i) an organic oil;

(ii) an optional adhesion agent; and

(iii) a tackifier consisting essentially of an organic material having a glass transition temperature of no less than about 120°

C. and a naphthenic oil present in sufficient amount to give the tackifier a kinematic viscosity ranging from about 3,000 to about 5,000 centistokes at 100°

C.;

said organic oil being compatible with the base granules, the tackifier, and the optional adhesion agent.

16. Method in accordance with claim 15 wherein said composition is devoid of said adhesion agent.