24/06/2005 - Controller General of Patents, Designs, and Trade Marks

(21) Application No. 2136/DEL/1997 A (22) Date of filing of Application: 31/07/1997
(54) Title of the invention: “A PROCESS FOR THE PREPARATION OF WATER DISPERSABLE
BENTONITE GRAFTED ACRYLIC COPOLYMER.”
(51) International Classification 7 : C 09K 3/10,
D 06M 15/00
(30) Priority Data :
(31) Document No.: NA
(32) Date : NA
(33) Name of convention country : NA
(66) Filed U/s 5(2) : NIL
(61) Patent of addition to application No. : NA
(62) Filed on : NA
(63) Divisional to Application No. :NIL
(64) Filed on : NA
(57) Abstract:
(71) Name of the applicant:
COUNCIL OF SCIENTIFIC AND
INDUSTRIAL RESEARCH.
Address of the Applicant:
Rafi Marg, New Delhi 110 001, india.
(72) Name of the Inventor:
YALAVARTHI
LAKSHMINARAYANA
THIRUMALACHARI RAMASAMI
GANGA RADHAKRISHNAN
KORITALA PANDURANGA RAO
SAMAYAVARAM RAMALINGAM
KARIKASSERY ANTONY RAPHEL
KRISHNASWAMI PARTHASARATHI
KRISHNA BALLABH GUPTA
KONDAPURAM VIJAYA
RAGHAVAN
A process for the preparation of water dispersable bentonite grafted acrylic copolymer by heating
an aqueous dispersion of bentonite to a temperature in the range of 55 o -95 o C, copolymerising an
acid acrylic monomer in the Bentonite dispersion medium in presence of a free radical initiator
over a period of 3.5 to 7.5 hours, cooling the resultant graft polymer to a temperature in the range
of 25 o – 35 o C to obtain acrylic copolymer, adjusting the pH of the end product adding sodium
hydroxide, ammonia hydroxide or trichanolamine to the end product in the range of 4.5 – 5.5.
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