Title of Invention

A NATURAL RESIN BASED ADHESIVE

Abstract

This invention relates to a water soluble lamination adhesive comprising 8 to 35% by weight of a natural resin such as Kordufan gum (gum arabic) in a proportion of 50 to 80% water by weight, to which is added additives such as humectant, colloid modifier, fluidifier, plasticiser, stabilizer and catalyst wherein plasticisers are upto 1 to 4% by weight from the compounds sodium chloride, calcium chloride, sodium Nitrate; humectants acting as plasticisers also are upto 1 to 25% by weight from the compounds of ethylene glycol, diethylene glycol, glycerin, glucose, sorbitol, polyethylene glycol; colloid modifiers acting also as fluidifier and plasticiser upto 1 to 5% by weight from the compounds of Urea and Dimethylol Urea; stabilizer upto 0.05 to 1% by weight from the compounds of methyl paraben and ethyl paraben and catalyst upto 0.5% to 5% by weight from the compounds of salicylic acid, tartaric acid and aluminium sulphate.

Full Text

1A FIELD OF THE INVENTION: This invention relates to a natural resin based adhesive. This invention further relates to a natural resin based water soluble industrial adhesive, to be used as a laminating agent in flexible packaging industries. BACKGROUND OF THE INVENTION: Several additives are known in the field of laminates, such as acrylic emulsion, polyvinyl acetate, casin and polyurethane or polyurethane dispersion. However most of the adhesives which are used in solvent based machines are toxic and require at least 24 hours as curing time to get the proper peel strength of the laminated substrates. Further, most of the conventional lamination adhesives are typical with regard to therein production, i.e. wet lamination adhesives can be used in wet lamination machines and dry lamination adhesives are used in dry lamination machines. OBJECTS OF THE INVENTION: It is therefor an object of this invention to propose a natural resin based adhesive which does not require long period for curing. It is a further object of this invention to propose a natural resin based adhesive which can be used both in a dry lamination and a wet lamination machine, thereby making it cost-effective. Another object of this invention is to propose a natural resin based adhesive which is non-toxic, odorless bio-degradable. These and other objects and advantages of the invention will be apparent on reading the ensuing description. -2- BRIEF DESCRIPTION OF THE INVENTION: According to this invention is provided a natural resin based adhesive. A natural resin is soaked in demineralised water at ambient temperature for few hours. After complete dissolution, certain additives like plasticizer, colloid modifier, humectants, fluidifier, catalyst, extender and stabilizer are added to make a complete solution in order to modify the bond strength. The same additives may be used in different way in and in different composition to modify the peel strength as per the requirements of the user. The natural resin used is Kordufar Gum (Gum arabic) in a proportion of 8 to 35% and water in a proportion of 50 to 80%. The balance is made up with plasticizer, colloid modifier, humectants, fluidifier, catalyst and stabilizer. These compounds are selected from urea and Dimethylol Urea, added in a proportion of 1 to 5% ; Ethylene Glycol, Di-ethylene, Polyethylene Glycol, Sorbetol, Glueose; Tartaric and Salicylic Acid; Methyl Paraben and Ethyl Paraben and salts such as Sodium Nitrate, Sodium Chloride, Aluminium Sulphate, Calcium Chloride etc. Compounds selected from urea and dimethylol urea are used in 1 to 5% by weight and functions colloid modifier, fluidifier and plasticizer. The stabilizers used are methyl paraben or ethyl paraben. Catalysts are selected from compounds such as salicylic acid, tartaric acid, aluminium sulphate compounds selected from glycerin, drethylene glycol, polyethylene glycol, sorbitol and glucose function both as humectants and plasticizers whereas sodium nitrate, calcium chloride and sodium chloride function solely as plasticizers. The stabilizers are added in a proportion of 0.05 to 1% by weight of the composition. Catalyst is added in a proportion of upto 5% by weight. In separate embodiments salicylic acid is added in 0.5 to 5%, tartaric acid in 1 to 5%, preferably 1 to 3% -3- and aluminium sulphate in 0.05 to 3% by weight. The humectants and plasticizers such as Glycerin is present in S to 15% by weight, glucose in 5 to 10% by weight, while sorbitol is present in 5 to 25% by weight. The other representatives such as diethylene glycol and polyethylene glycol are present in approximately 1 to 6% by weight, while ethylene glycol may be present in 5 to 20% by weight. The plasticizers are used in upto 4% by weight, where sodium nitrate is preferably is used in 1 to 4%, sodium chloride in 0.1 to 3% and calcium choloride in 1 to 3% by weight. According to the invention therein provided a water soluble lamination adhesive comprising 8 to 35% by weight of a natural resin such as Kordufan gum (gum arabic) in a proportion of 50 to 80% water by weight, to which is added additives such as humectant, colloid modifier, fluidifier, plasticiser, stabilizer and catalyst wherein plasticisers are upto 1 to 4% by weight from the compounds sodium chloride, calcium chloride, sodium Nitrate; humectants acting as plasticisers also are upto 1 to 25% by weight from the compounds of ethylene glycol, diethylene glycol, glycerin, glucose, sorbitol, polyethylene glycol; colloid modifiers acting also as fluidifier and plasticiser upto 1 to 5% by weight from the compounds of Urea and Dimethylol Urea; stabilizer upto 0.05 to 1% by weight from the compounds of methyl paraben and ethyl paraben and catalyst upto 0.5% to 5% by weight from the compounds of salicylic acid, tartaric acid and aluminium sulphate. The invention will now be explained in greater details with the help of the following non-limiting examples. Example 1: Composition in percentage by weight of constituents Kordufan Gum -15% Urea - 3.5% Sodium Nitrate -1% -4- Glycerin -15% Tartaric Acid - 3% Methyl Paraben - 0.05% Water - 62% Kordufan gum (gum arable) is soaked in demoralised water at 27°C for about 3 hours. After complete dissolution, urea, sodium nitrate, glycerine, tartaric acid, and methyl paraben are added with constant stirring to obtain the adhesive composition. Composition in percentage by weight of constituents Kordufan Gum - 28% Sodium Chloride - 3% D -Glucose - 8% Poly Ethylene Glycol - 2.5% Aluminium Sulphate -1.5% Ethyl Paraben IP -1% Water - 56% Kordufan gum (gum arabic is soaked in demineralised water at 27°C for about 3 hours. After complete dissolution, urea, sodium chloride, D-glucose, plyethylene glycol, aluminium sulphate and ethyl paraben are added with constant stirring to obtain the adhesive composition. The adhesive thus obtained is non-toxic, biodegradable, odorless, and is fee from coliform microbes. It has a long shelf life. -5-WE CLAIM: 1. A water soluble lamination adhesive comprising 8 to 35% by weight of a natural resin such as Kordufan gum (gum arabic) in a proportion of 50 to 80% water by weight, to which is added additives such as humectant, colloid modifier, fluidifier, plasticiser, stabilizer and catalyst wherein plasticisers are upto 1 to 4% by weight from the compounds sodium chloride, calcium chloride, sodium Nitrate; humectants acting as plasticisers also are upto 1 to 25% by weight from the compounds of ethylene glycol, diethylene glycol, glycerin, glucose, sorbitol, polyethylene glycol; colloid modifiers acting also as fluidifier and plasticiser upto 1 to 5% by weight from the compounds of Urea and Dimethylol Urea; stabilizer upto 0.05 to 1% by weight from the compounds of methyl paraben and ethyl paraben and catalyst upto 0.5% to 5% by weight from the compounds of salicylic acid, tartaric acid and aluminium sulphate. 2. The adhesive as claimed in claim 6, wherein diethylene and polyethylene glycol are used in 1 to 6% by weight ethylene glycol in 5 to 20% by weight, glucose in 5 to 10% and sorbitol in 5 to 25% by weight. 3. A water soluble lamination adhesive as herein described and illustrated. This invention relates to a water soluble lamination adhesive comprising 8 to 35% by weight of a natural resin such as Kordufan gum (gum arabic) in a proportion of 50 to 80% water by weight, to which is added additives such as humectant, colloid modifier, fluidifier, plasticiser, stabilizer and catalyst wherein plasticisers are upto 1 to 4% by weight from the compounds sodium chloride, calcium chloride, sodium Nitrate; humectants acting as plasticisers also are upto 1 to 25% by weight from the compounds of ethylene glycol, diethylene glycol, glycerin, glucose, sorbitol, polyethylene glycol; colloid modifiers acting also as fluidifier and plasticiser upto 1 to 5% by weight from the compounds of Urea and Dimethylol Urea; stabilizer upto 0.05 to 1% by weight from the compounds of methyl paraben and ethyl paraben and catalyst upto 0.5% to 5% by weight from the compounds of salicylic acid, tartaric acid and aluminium sulphate.

Documents:

00101-kol-2005-abstract .pdf

00101-kol-2005-claims .pdf

00101-kol-2005-correspondence.pdf

00101-kol-2005-description(complete).pdf

00101-kol-2005-description(provisional).pdf

00101-kol-2005-form-1.pdf

00101-kol-2005-form-18 .pdf

00101-kol-2005-form-2.pdf

00101-kol-2005-form-26 .pdf

00101-kol-2005-form-3.pdf

00101-kol-2005-form-5.pdf

00101-kol-2005-letters patent .pdf

101-KOL-2005-CORRESPONDENCE.pdf

101-KOL-2005-FORM 15.pdf

101-KOL-2005-FORM 27-1.1.pdf

101-KOL-2005-FORM 27.pdf

101-KOL-2005-PA.pdf