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US4549897A Expired / Lapsed US ⏱️ 0.0 years remaining

Protein degraded pre-vulcanized natural rubber coated slow release fertilizers

Assignee: BOARD OF RUBBER RESEARCH INSTITUTE OF MALAYSIA
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Filing: 1982-08-17
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Granted: 1985-10-29
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Expires: 2002-08-17
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Abstract

Abstract An agricultural material composition comprises particles of an agricultural material, e.g. a fertilizer, coated with a layer of protein degraded pre-vulcanized natural rubber to provide slow-release properties. The particles preferably have a diameter of from 0.5 to 12 mm, and the thickness of the rubber layer is preferably from 10 to 250 microns.

Inventors

  • 👤 Yeoh C. Seng
  • 👤 Chen S. Fong

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-07 14:34
CPC Classifications
A; A01; A01N; A01N25/00; A01N25/26; C; C05; C05G; C05G5/00; C05G5/30; C05G5/37; C08; C08C; C08C1/00; C08C1/02; C08C1/04; Y; Y10; Y10S; Y10S71/00; Y10S71/903

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 21 words
The slow release fertilizer composition which comprises particles of a fertilizer coated with a layer of protein degraded pre-vulcanized natural rubber.
Claim 2
Dependent Claim 21 words
The slow release fertilizer composition which comprises particles of a fertilizer coated with a layer of protein degraded pre-vulcanized natural rubber.
Claim 3
Dependent Claim 28 words
A composition as claimed in claim 1 wherein the fertilizer is a potassium or ammonium salt of sulphuric, nitric or phosphoric acids or urea or a mixture thereof.
Claim 4
Dependent Claim 47 words
An agricultural material composition which comprises particles of an agricultural material selected from the group consisting of plant growth regulants, hormones, pesticides, weed killers, seeds and agents active against undesired, or active to encourage desired soil microorganisms coated with a layer of protein degraded pre-vulcanized natural rubber.
Claim 5
Dependent Claim 47 words
An agricultural material composition which comprises particles of an agricultural material selected from the group consisting of plant growth regulants, hormones, pesticides, weed killers, seeds and agents active against undesired, or active to encourage desired soil microorganisms coated with a layer of protein degraded pre-vulcanized natural rubber.
Claim 6
Dependent Claim 24 words
The composition as claimed in any one of claims 1 to 3 wherein the particles have a diameter of from 0.5 to 12 mm.
Claim 7
Dependent Claim 26 words
The composition as claimed in any one of claims 1 to 3 wherein the thickness of the layer of rubber is from 10 to 250 μm.
Claim 8
Dependent Claim 33 words
The composition as claimed in any one of claims 1 to 3 wherein the amount of rubber in the coating is from 1 to 25% by weight on the weight of the particles.
Claim 9
Independent Claim 49 words
A method of making a slow release fertilizer composition which comprises contacting particles of a fertilizer with a protein degraded pre-vulcanized natural rubber latex and coagulating and drying the rubber on the particles of the fertilizer thereby coating the particles with a film of protein degraded pre-vulcanized natural rubber.
Claim 10
Independent Claim 49 words
A method of making a slow release fertilizer composition which comprises contacting particles of a fertilizer with a protein degraded pre-vulcanized natural rubber latex and coagulating and drying the rubber on the particles of the fertilizer thereby coating the particles with a film of protein degraded pre-vulcanized natural rubber.
Claim 11
Independent Claim 78 words
The method of making a coated particulate agricultural material composition which comprises contacting particles of an agricultural material selected from the group consisting of plant growth regulants, hormones, pesticides, weed killers, seeds and agents active against undesired, or active to encourage desired soil microorganisms with a protien degraded prevulcanized natural rubber latex and coagulating and drying the rubber on the particles of the agricultural material thereby coating the particles with a film of protein degraded pre-vulcanized natural rubber.
Claim 12
Independent Claim 78 words
The method of making a coated particulate agricultural material composition which comprises contacting particles of an agricultural material selected from the group consisting of plant growth regulants, hormones, pesticides, weed killers, seeds and agents active against undesired, or active to encourage desired soil microorganisms with a protien degraded prevulcanized natural rubber latex and coagulating and drying the rubber on the particles of the agricultural material thereby coating the particles with a film of protein degraded pre-vulcanized natural rubber.
Claim 13
Dependent Claim 45 words
The method as claimed in either claim 7 or claim 8 comprising providing a fluidized bed of the particles and introducing into the bed protein degraded natural rubber latex in droplet form whereby to form a coating of protein degraded natural rubber over the particles.

References Cited (Backward Citations)

US2511722A Cited
US3639259A Cited
US4023955A Cited
CA1047272A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-10-28 1989-04-29 1989-10-29 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-10-28 1993-04-29 1993-10-29 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-10-28 1997-04-29 1997-10-29 $7700.00 Window Closed / Lapsed

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