Coating composition for a paper substrate

Abstract

Present invention relates to a coating composition for a paper substrate comprising a plasticizer, a synthetic polymer, cationic starch, pectin, anionic starch, and water. The present inventors have surprisingly found that the coating composition of the invention which, when applied to a paper substrate, results in a coated paper substrate having an increases grease, oil and / or wax resistance.

Description

PT-2134-WO-PCTCOATING COMPOSITION FOR A PAPER SUBSTRATECROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of European Application No. 24198793.2, filed September 6, 2024, and European Application No. 25173492.7, filed April 30, 2025, each of which is incorporated by reference herein in its entirety.FIELD OF THE INVENTION

[0002] The present invention relates to a coating composition for a paper substrate. The present invention further relates to a process for preparing said coating composition. The present invention further relates to a kit for preparing said coating composition. The present invention further relates to a process for coating a paper substrate with said coating composition. The present invention further relates to a paper substrate coated with said coating composition. The present invention further relates to a use of said coating composition.BACKGROUND OF THE INVENTION

[0003] Fluorine-based coatings, such as per- and polyfluoroalkyl compounds (PF AS), have been widely used in paper and paperboard production due to their unique properties of providing resistance to both water and oil. In the context of food paper, a PF AS surface coating results in the perfluorinated tail being positioned outward, thereby offering repellency to oil and water. However, PF AS compounds are remarkably resilient; resisting biodegradation, heat degradation, hydrolysis, and metabolism. Consequently, there is an industry requirement to eliminate the use of fluorine-based coatings as grease barriers. Hence, there is a need in the industry to eliminate the use of fluorine-based coatings as grease barriers.

[0004] WO2024 / 015739 Al discloses a coating composition comprising a n-OSA modified starch.

[0005] CN111749042A and CN107313287A disclose a coating composition comprising a styrene acrylate copolymer.

[0006] EP 4 122 988 Al discloses a barrier coating composition comprising acrylicPT-2134-WO-PCT latex, anionic starch and chemically modified starch.

[0007] However, there remains a need to provide an improved oil-proof coating for food packaging.

[0008] It is an object of the present invention to provide a coating composition for a paper substrate.

[0009] It is a further object of the present invention to provide a process for preparing said coating composition.

[0010] It is a further object of the present invention to provide a kit for preparing said coating composition.

[0011] It is a further object of the present invention to provide a process for coating paper.

[0012] It is a further object of the present invention to provide a paper coated with said coating composition.

[0013] It is a further object of the present invention to provide a use of said coating composition.SUMMARY OF THE INVENTION

[0014] The present invention relates to a coating composition for a paper substrate comprising a) A plasticizer, b) A synthetic polymer, c) Cationic starch, d) Pectin, e) Anionic starch, and f) Water.

[0015] The present inventors have surprisingly found that the specific combination of plasticizer, synthetic polymer, cationic starch, pectin and anionic starch results in a coating composition, which, when applied to paper, results in a coated paper substrate having an increased grease, oil and / or wax resistance, as demonstrated in the appended examples.

[0016] Without wishing to be bound by any theory the present inventors believe that the synthetic polymer and anionic starch enhance the paper’s resistance to grease, oil, and / orPT-2134-WO-PCT wax after the coating composition is applied. The plasticizer aids in forming a film on the paper once the coating composition is applied. The pectin ensures the formation of a sufficiently flexible film on the paper after the application of the coating composition, preventing the appearance of cracks on the coated paper. The cationic starch ensures that the applied coating composition stays on the paper’s surface, preventing and / or reducing the coating composition’s impregnation within the paper. As a result, the final composition provides an appropriate coating composition for a paper substrate, offering the desired grease resistance while preserving other essential parameters such as flexibility.

[0017] The present invention also relates to a process for preparing said coating composition.

[0018] The present invention also relates to a kit for preparing said coating composition.

[0019] The present invention also relates to a process for coating a paper substrate.

[0020] The present invention also relates to paper coated with said coating composition.

[0021] The present invention also relates to a use of said coating composition.

[0022] Representative features of the invention are set out in the following clauses, which stand alone or may be combined, in any combination, with one or more features disclosed in the text and / or drawings of the specification.1. A coating composition for a paper substrate, preferably for paper food packaging, comprising a) A plasticizer in amount of from 50 to 80 wt.% on total dry solids, b) A synthetic polymer in an amount of from 0.5 to 10 wt.% on total dry solids, c) Anionic starch in an amount of from 10 to 45 wt.% on total dry solids, d) Pectin in an amount of from 0.1 to 10 wt.% on total dry solids, e) Cationic starch in an amount of from 0.1 to 10 wt.% on total dry solids, and f) Water.2. Coating composition according to clause 1, wherein the plasticizer is a hydrolysed starch, preferably the hydrolysed starch comprises glucose syrup,PT-2134-WO-PCT fructose syrup, maltodextrin, dextrin or any combination thereof preferably glucose syrup, maltodextrin, or any combination thereof.3. Coating composition according to clause 2, wherein the glucose syrup has a dextrose equivalent of 20 or more.4. Coating composition according to clause 2 or 3, wherein the maltodextrin has a dextrose equivalent of less than 25, preferably between 3 and 25.5. Coating composition according to any one of clauses 1 -4, wherein the plasticizer is in amount of from 55 to 75 wt.%, preferably from 60 to 70 wt.%, more preferably from 62 to 68 wt.% on total dry solids.6. Coating composition according to any one of clauses 1-5, wherein the synthetic polymer is an acrylic polymer, preferably the acrylic polymer is an (meth)acrylic copolymer, a styrene / (meth)acrylic copolymer or a combination thereof.7. Coating composition according to any one of clauses 1-6, wherein the synthetic polymer is in an amount of from 1 to 8 wt.%, preferably from 1.5 to 6 wt.%, more preferably from 2 to 5 wt.% on total dry solids.8. Coating composition according to any one of clauses 1-7, wherein the anionic starch is an anionic anhydride modified starch, preferably the anionic anhydride modified starch is an alkyl or alkenyl succinic anhydride modified starch, preferably octenyl succinic anhydride modified starch.9. Coating composition according to any one of clauses 1-8, wherein the anionic starch is in an amount of from 15 to 40 wt.%, preferably from 20 to 35 wt.%, more preferably from 25 to 30 wt.% on total dry solids.10. Coating composition according to any one of clauses 1-9, wherein the pectin is high-methoxyl pectin.PT-2134-WO-PCT11. Coating composition according to clause 10, wherein the degree of methoxyl ati on is greater than or equal to 50%.12. Coating composition according to any one of clauses 1-11, wherein the pectin is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids.13. Coating composition according to any one of clauses 1-12, wherein the cationic starch is an ammonium, sulfonium or phosphonium substituted cationic starch.14. Coating composition according to any one of clauses 1-13, wherein the cationic starch is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids.15. Coating composition according to any one of clauses 1-14, a) the plasticizer is in amount of from 15 to 35 wt.%, preferably from 20 to 30 wt.%, more preferably from 22 to 28 wt.% on total amount of the coating composition; b) the synthetic polymer is an amount from 0.1 to 4 wt.%, preferably from 0.5 to 3 wt.%, more preferably from 0.8 to 2 wt.% on total amount of the coating composition; c) the anionic starch is in an amount of from 2 to 18 wt.%, preferably from 5 to 15 wt.%, more preferably from 8 to 12 wt.% on total amount of the coating composition; d) the pectin is in amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; e) the cationic starch is in an amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; and / or f) the water is in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.PT-2134-WO-PCT16. Coating composition according to any one of clauses 1-15 having a Brookfield viscosity measured at 40 °C of from 50 to 5000 mPa.s, preferably from 100 to 3000 mPa.s, more preferably from 200 to 2000 mPa.s.17. A process for preparing the coating composition according to any one of clauses 1-16 comprising the following steps: a) Preparing a mixture of water, the cationic starch as defined in any one of clauses 1- 16 and the anionic starch as defined in any one of clauses 1-16; b) Heating the mixture obtained in step a) to a temperature of from 105 to 120 °C for 1- 10 minutes, preferably about 5 minutes; c) Lowering the temperature to 70 to 95 °C for 1 to 30 minutes, preferably about 15 minutes; d) Adding the pectin as defined in any one of clauses 1-16 to the mixture obtained in step c) and stirring for 1 to 30 minutes, preferably about 15 minutes; e) Lowering the temperature to below 50 °C, preferably below 45 °C; and f) Adding the synthetic polymer as defined in any one of clauses 1-16 and the plasticizer as defined any one of clauses 1-16 to mixture obtained in step e) and stirring for 1 to 30 minutes, preferably about 15 minutes, to afford the coating composition.18. A kit for preparing the coating composition for a paper substrate according to any one of clauses 1-16 comprising i) Plasticizer as defined in any one of clauses 1-16, ii) Synthetic polymer as defined in any one of clauses 1-16, iii) Cationic starch as defined in any one of clauses 1-16, iv) Pectin as defined in any one of clauses 1-16, v) Anionic starch as defined in any one of clauses 1-16, and vi) a set of instructions for manufacturing the coating composition using the plasticizer, the synthetic polymer, the cationic starch, the pectin and the anionic starch.19. A process for coating a paper substrate by treating the paper substrate with the coating composition according to any one of clauses 1-16 followed by drying.PT-2134-WO-PCT20. Paper substrate obtainable by the process according to clause 19.21. A paper substrate coated with the coating composition according to any one of clauses 1-16.22. Paper substrate according to clause 20 or clause 21, wherein the paper is coated with the coating composition between 1 and 10 g / m2, preferably between 2 and 8 g / m2, more preferably between 4 and 6 g / m2.23. Paper substrate according to any one of clauses 20-22, wherein the uncoated paper substrate has a weight basis of from 20 g / m2to 40 g / m2, preferably from 25 g / m2to 35 g / m2, more preferably from 28 g / m2to 32 g / m2.24. Paper substrate according to any one of clauses 20-23 having a Grease Resistance Kit Rating of at least KIT6, preferably at least KIT8, more preferably at least KIT9.25. Use of the coating composition according to any one of clauses 1-16 to improve the oil and / or grease resistance in a food packaging, preferably a paper food packaging.DETAILED DESCRIPTION

[0023] The term "comprising", as used herein and in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It needs to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression "a composition comprising components A and B" should not be limited to compositions consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the composition are A and B. Accordingly, the terms "comprising" and "including" encompass the more restrictive terms "consisting essentially of' and "consisting of'.PT-2134-WO-PCTCoating composition

[0024] A first aspect of the invention is providing a coating composition for paper, preferably for paper food packaging, comprising a) A plasticizer in amount of from 50 to 80 wt.% on total dry solids, b) A synthetic polymer in an amount of from 0.5 to 10 wt.% on total dry solids, c) Anionic starch in an amount of from 10 to 45 wt.% on total dry solids, d) Pectin in an amount of from 0.1 to 10 wt.% on total dry solids, e) Cationic starch in an amount of from 0.1 to 10 wt.% on total dry solids, and f) Water, preferably in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.

[0025] As appreciated by the skilled person the total amount of total dry solids of components constituting the coating composition should add to 100 wt.%.

[0026] Preferably, the plasticizer is in an amount of from 55 to 75 wt.%, preferably from 60 to 70 wt.%, more preferably from 62 to 68 wt.% on total dry solids.

[0027] Preferably, the synthetic polymer is in an amount of from 1 to 8 wt.%, preferably from 1.5 to 6 wt.%, more preferably from 2 to 5 wt.% on total dry solids.

[0028] Preferably, the anionic starch is in amount of from 15 to 40 wt.%, preferably from 20 to 35 wt.%, more preferably from 25 to 30 wt.% on total dry solids.

[0029] Preferably, the pectin is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids.

[0030] Preferably, the cationic starch is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids.

[0031] More preferably, the coating composition for paper of the invention comprises a) the plasticizer is in an amount of from 55 to 75 wt.%, preferably from 60 to 70 wt.%, more preferably from 62 to 68 wt.% on total dry solids; b) the synthetic polymer is in an amount of from 1 to 8 wt.%, preferably from 1.5 to 6 wt.%, more preferably from 2 to 5 wt.% on total dry solids; c) the anionic starch is in amount of from 15 to 40 wt.%, preferably from 20 to 35 wt.%, more preferably from 25 to 30 wt.% on total dry solids;PT-2134-WO-PCT d) the pectin is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids; e) the cationic starch is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids; and / or f) Water, preferably in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.

[0032] Preferably, the coating composition for paper is according to the invention, wherein a) the plasticizer is in amount of from 15 to 35 wt.%, preferably from 20 to 30 wt.%, more preferably from 22 to 28 wt.% on total amount of the coating composition; b) the synthetic polymer is an amount from 0.1 to 4 wt.%, preferably from 0.5 to 3 wt.%, more preferably from 0.8 to 2 wt.% on total amount of the coating composition; c) the anionic starch is in an amount of from 2 to 18 wt.%, preferably from 5 to 15 wt.%, more preferably from 8 to 12 wt.% on total amount of the coating composition; d) the pectin is in amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; e) the cationic starch is in an amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; and / or f) the water is in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.

[0033] Hence, the weight percentage defined on total dry solids (i.e. total dry solids of the coating composition includes the components constituting the coating composition excluding water, whereas the weight percentage defined on total amount of the coating composition includes the components constituting the coating composition including water.

[0034] As appreciated by the skilled person the total amount of components constituting the coating composition should add to 100 wt.% relative to the total amount of the coating composition.PlasticizerPT-2134-WO-PCT

[0035] The plasticizer is selected from the list consisting of hydrolysed starch, sucrose, hydrolysed cellulose, glucose, glycol, glycerol, sorbitol, maltitol and combinations thereof. Preferably, the plasticizer is a hydrolysed starch.

[0036] Starch is a polymeric carbohydrate consisting of a large number of glucose units joined by glycosidic bonds. This polysaccharide is produced by most green plants as energy storage. It is the most common carbohydrate in human diets and is contained in large amounts in staple foods. Starches useful in the present disclosure can come from any plant source including but not limited to: potatoes, wheat, maize (corn), rice, tapioca, quinoa, cassava, and the like. Pure starch is a white, tasteless and odorless powder that is insoluble in cold water or alcohol. It consists of two types of molecules: the linear and helical amylose and the branched amylopectin. Depending on the plant, starch generally contains 1 to 25% amylose and 75 to 99% amylopectin by weight. When it is isolated directly from the plant source it is most often referred to as “native starch”. Native starch requires heat to thicken or gelatinize. When a starch is pre-cooked, it can then be used to thicken instantly in cold water. This is referred to as a pregelatinized starch.

[0037] The plasticizer may be a hydrolysed starch. Native starch can be hydrolysed into simpler carbohydrates by temperature, acids, various enzymes, or a combination of the three. The resulting fragments are known as hydrolysed starch. The resulting syrup can be filtered or otherwise clarified to remove any objectionable flavour or colour, and further refined and evaporated to reduce the amount of water. The term, “syrup”, as used herein, refers to aqueous solutions of sugars or starch hydrolysates. In the acid-enzyme process, starch is first partially hydrolysed or liquefied by forming an aqueous suspension containing starch and incorporating therein an acid such as hydrochloric acid. The suspension is then heated to high temperatures to partially hydrolyse the starch. The suspension may be cooled and treated at a suitable concentration and pH range to enzymatically convert the partially hydrolysed starch. In the enzyme-enzyme conversion process, generally, a starch slurry is formed, and a starch liquefying enzyme is added, and the starch slurry is heated to partially hydrolyse the starch. The partial hydrolysis is usually carried out at a specific temperature range. Any suitable starch liquefying enzyme may be used to partially hydrolyse the starch. The partially hydrolysed starch slurry may then be treated to convert the starch. The extent of conversion is typically quantified by dextrose equivalent (DE), which is roughly the fraction of the glycosidic bonds in starch that have been broken. For example, maltodextrin is a lightly hydrolysed (DE 4-20 orPT-2134-WO-PCT10-20) starch product used as a bland-tasting filler and thickener. Various glucose syrups (DE 30-70), also called com syrups in the US, are a type of hydrolysed starch that are viscous solutions used as sweeteners and thickeners in many kinds of processed foods. Dextrose (DE 100), commercial glucose, is prepared by the complete hydrolysis of starch.

[0038] The hydrolysed starch may comprise or consists of glucose syrup, fructose syrup, maltodextrin, dextrin or any combination thereof; preferably the hydrolysed starch may comprise glucose syrup, maltodextrin, or any combination thereof.

[0039] Preferably, the glucose syrup and / or fructose syrup has a dextrose equivalent of 20 or more, more preferably of 30 or more, even more preferably of 60 or more, most preferably of 95 or more. More preferably, the glucose syrup has a dextrose equivalent of 20 or more, more preferably of 30 or more. Most preferably the glucose syrup has a dextrose equivalent of from 30 to 50, or from 35 to 45, or from 38 to 40.

[0040] Preferably, the maltodextrin has a dextrose equivalent of less than 25, preferably of from 3 to 25, more preferably from 16 to 22.

[0041] The hydrolysed starch may comprise- Maltodextrin of from 20 to 30 wt.% on dry solids relative to the hydrolysed starch, preferably from 20 to 25 wt.% on dry solids relative to the hydrolysed starch, more preferably from 21 to 24 wt.% on dry solids relative to the hydrolysed starch; and Glucose syrup of from 60 to 80 wt.% on dry solids relative to the hydrolysed starch, preferably from 65 to 75 wt.% on dry solids relative to the hydrolysed starch, more preferably from 68 to 72 wt.% on dry solids relative to the hydrolysed starch.

[0042] The hydrolysed starch may also comprise other components such as xanthan gum or preservatives, preferably in an amount of less than 1 wt.% relative to the hydrolysed starch.

[0043] The plasticizer may be a monosaccharide such as glucose or sucrose.

[0044] The plasticizer may be a polyol selected from the list consisting of glycol, glycerol, sorbitol, maltitol and combinations thereof.

[0045] The plasticizer may be a hydrolysed cellulose, preferably the hydrolysed cellulose is glucose, cellobiose, or higher glucose polymers; and includes dimers and oliogmers.

[0046] The plasticizer facilitates the creation of a film on the paper after application of the coating composition to the paper.PT-2134-WO-PCT

[0047] Examples of the plasticizer may be commercially available hydrolysed starch such as Cargill product C*icoat 41175.Synthetic polymer

[0048] The synthetic polymer is selected from acrylic polymer, polyvinyl alcohol, polyamine, polyacrylamides, polyamides, styrene-butadiene rubber, and combinations thereof, preferably the synthetic polymer is an acrylic polymer.

[0049] "Acrylic polymer", as used herein is meant to include polymers, copolymers and terpolymers formed from alkyl methacrylate and alkyl acrylate monomers, and mixtures thereof. The monomer mixture may comprise the alkyl methacrylate monomer, preferably methyl methacrylate comprising from 50 to 100 wt.% relative to the monomer mixture, preferably 70 to 100 wt.%. Other acrylate and methacrylate monomers or other ethylenically unsaturated monomers, such as styrene, alpha methyl styrene, acrylonitrile, and low-level crosslinkers, may also be included in the monomer mixture, preferably comprising 0 to 50 wt.% of the monomer mixture, more preferably 0 to 30 wt.%. Styrene is particularly preferred among these additional components. Other methacrylate and acrylate monomers useful in the monomer mixture include, but are not limited to, methyl acrylate, ethyl acrylate and ethyl methacrylate, butyl acrylate and butyl methacrylate, iso-octyl methacrylate and acrylate, lauryl acrylate and lauryl methacrylate, stearyl acrylate and stearyl methacrylate, isobornyl acrylate and methacrylate, methoxy ethyl acrylate and methacrylate, 2-ethoxy ethyl acrylate and methacrylate, dimethylamino ethyl acrylate and methacrylate monomers. Alkyl (meth) acrylic acids such as methacrylic acid and acrylic acid can be useful for the monomer mixture. Most preferably, the acrylic polymer is a copolymer having 70 - 100 wt.% of methyl methacrylate units and from 0 to 30 wt.% of one or more Cl-8 straight or branched alkyl acrylate units.

[0050] The acrylic polymer may be an (meth)acrylic copolymer, a styrene / acrylic copolymer or a combination thereof.

[0051] Preferably, the synthetic polymer, more preferably an acrylic or methacrylic homo- or copolymer, has a Tgof less than 20 °C, preferably less than 10 °C, even more preferably less than 0 °C, even more preferably less than -10 °C, most preferably less than -20 °C; or the synthetic polymer, preferably an acrylic / styrene or methacrylic / styrene copolymer, has a Tgof less than 20 °C, preferably less than 10 °C, even more preferably less than 0 °C, even more preferably less than -10 °C, most preferably less than -20 °C. As appreciated by thePT-2134-WO-PCT skilled person the Tgor glass transition temperature can be measured using differential scanning calorimetry (DSC).

[0052] The synthetic polymer, preferably the acrylic polymer, may have a Brookfield viscosity at 25 °C of from 1 to 1000 mPa.s, preferably of from 100 to 750 mPa.s, more preferably of from 400 to 600 mPa.s. There are different techniques in the field available for the skilled person to measure the Brookfield viscosity such as a Brookfield Viscometer DV-II.

[0053] The synthetic polymer, preferably the acrylic polymer, may have a weight average molecular weight between 100 g / mol and 500,000 g / mol or between 1,000 g / mol and 300,000 g / mol or between 10,000 and 150,000 g / mol.

[0054] The synthetic polymer contributes to the improved resistance of grease, oil and / or wax of the paper after application of the coating composition.

[0055] Examples of the synthetic polymer may be commercially available such as Arkema product ENCOR® G-3030 or Baripel G3030.Anionic starch

[0056] The anionic starch is obtained by introducing an anionic substituent on a hydroxyl group of glucose constituting the starch.

[0057] Preferably, the anionic starch is an anionic anhydride modified starch, wherein the anionic anhydride modified starch used in the present compositions is starch that has been chemically modified in a starch esterification process by reacting hydroxyl groups on the starch with, for example, n-octenyl succinic anhydride to form a n-OSA starch. The degree of substitution of the available hydroxyl groups with ester functionalities has been found to affect the physiochemical properties of the starch. It has been found that in starches wherein less than all of the hydroxyl groups have been substituted, the resulting starches will exhibit unique amphiphilic and interfacial properties.

[0058] Preferably, the anhydride is a cyclic anhydride. More preferably, the anhydride is chosen from the group consisting of maleic and succinic anhydrides. Most preferred succinic anhydrides are those chosen from the group consisting of (alkyl-, alkenyl-, aralkyl- or aralkenyl-) succinic anhydrides. Even more preferably, the anhydride is chosen from the group consisting of alkyl-succinic anhydrides and alkenyl-succinic anhydrides, wherein the alkyl or alkenyl group has from 0 to 22 carbon atoms or from 0 to 10 carbon atoms. Most preferably,PT-2134-WO-PCT the anhydride is an n-octenyl succinate anhydride (n-OSA). Hence, the anionic anhydride modified starch is preferably an octenyl succinic anhydride modified starch or n-OSA starch.

[0059] The n-OSA starch may be prepared by functionalizing a starch selected from maize starch, potato starch, sweet potato starch, wheat starch, rice starch, tapioca starch, sorghum starch, waxy maize starch, waxy potato starch, waxy sweet potato starch, waxy wheat starch, waxy rice starch, waxy tapioca starch, and waxy sorghum starch, preferably the n-OSA starch is prepared by functionalizing a maize starch.

[0060] It is known in the art how to manufacture an anionic anhydride-modified-starch (see O. B. Wurzburg, “Modified Starches: Properties and Uses”, 1986, pages 131-147). A n- OSA starch is a modified starch that has been chemically modified in a starch esterification process by reacting hydroxyl groups on the starch with n-octenyl succinic anhydride to form the n-OSA starch. n-OSA starches can also be characterized by the degree of substitution of the n-octenyl succinic groups. The degree of substitution is abbreviated at “DS”. It is a well understood and used nomenclature by those of skill in the art. A n-OSA starch having a degree of substation between 1% and 3% means that between 1% - 3% of n-octenyl succinic groups is bound on the starch on a weight basis. Preferably, the n-OSA starch has a DS below 10%, preferably below 5%, more preferably below 3.%. Preferably the n-OSA starch has a DS of 0.01% - 10%, more preferably from 0.1% to 5%, most preferably 0.5% - 3%.

[0061] The anionic starch may have a weight average molecular weight below 3,000,000 g / mol, preferably below 2,800,000 g / mol, more preferably below 2,500,000 g / mol. The anionic starch may have a weight average molecular weight between 50,000 g / mol and 3,000,000 g / mol or between 50,000 g / mol and 1,000,000 g / mol or between 100,000 and 800,000 g / mol. The skilled person is aware that there are techniques present in the art to measure a weight average molecular weight.

[0062] The anionic starch, preferably the anionic anhydride modified starch, provides to the improved resistance of grease, oil and / or wax of the paper after application of the coating composition.

[0063] Examples of the anionic starch may be commercially available anionic anhydride modified starch such as Cargill product C Stretch06392.PectinPT-2134-WO-PCT

[0064] Pectin is a plant-derived, water-soluble hydrocolloid, and is typically obtained from citrus fruits, apple pomace and sugar beets.

[0065] Pectin may be classified into high-methoxyl (HM) pectin and low-methoxyl (LM) pectin. Generally, pectin with degree of methoxylation of greater than or equal to 50%, such as 50% to 80% is classified as high-methoxyl pectin; and pectin with degree of methoxylation of less than 50% is classified as low-methoxyl pectin. In terms of gel formation, high-methoxyl pectin and low-methoxyl pectin are completely different in mechanism and technical solutions.

[0066] Preferably, the pectin is a high-methoxyl pectin having a degree of methoxylation of more than 50%, preferably of from 50 to 80%, more preferably from 55 to 70%. Preferably, degree of methoxylation of the high-methoxyl pectin described herein is greater than or equal to about 55%, greater than or equal to about 56%, greater than or equal to about 57%, greater than or equal to about 58%.

[0067] Preferably, the high-methoxyl pectin has an average molar mass of about 100,000 to 400,000 g / mol.

[0068] Preferably, the high-methoxyl pectin described herein is a high-methoxyl pectin produced from materials selected from the group consisting of: citrus (such as lemon, lime, orange, and grapefruit) peel, apple pomace, and sugar beets, or a combination thereof; preferably the high-methoxyl pectin is derived from citrus.

[0069] The pectin guarantees the formation of a film on the paper, which is sufficiently flexible after the coating composition is applied, ensuring that no cracks appear on the coated paper.

[0070] Examples of the pectin may be commercially available such as Cargill product line UniPECTINE® or Cargill product Pectin OSS30.Cationic starch

[0071] The cationic starch used in the coating compositions of the present disclosure may be any cationic starch. The cationic starch may be derived of any source such as dent com starch, waxy corn starch, potato starch, wheat starch, rice starch, sago starch, tapioca starch, sorghum starch, sweet potato starch, or mixtures thereof. Preferably, the cationic starch is derived from waxy corn starch. The cationic starches may be produced by any conventional manner. For example, the cationic starches may be produced by a chemical reaction of thePT-2134-WO-PCT starch with a modifying agent containing an amino, imino, ammonium, sulfonium, or phosphonium group. The chemical reaction may be an esterification or etherification reaction. The chemical reaction may be carried out in any conventional manner such as reacting the starch in an aqueous slurry form with the modifying agent, usually in the presence of an activating agent such as sodium hydroxide. Another process that may be used is a semi-dry process wherein the starch is reacted with the modifying agent in the presence of an activating agent such as sodium hydroxide, in a limited amount of water. Preferred modifying agents are those having an ammonium ion, and more preferably, where the ammonium ion is a quaternary ammonium ion. A particularly useful modifying agent is (3-chloro-2- hydroxypropyl)trimethylammonium chloride. If desired, the cationic starch may be treated in any conventional manner with known treating agents to render the cationic starches hydrophobic.

[0072] Cationic starches can also be characterized by the degree of substitution of the modifying agents. The degree of substitution is abbreviated at “DS”. It is a well understood and used nomenclature by those of skill in the art. Preferably the cationic starch has a degree of substation of 0.01 to 0.1. As appreciated by the skilled person the degree of substitution of cationic starches quantifies the number of hydroxyl groups substituted with cationic groups on each anhydroglucose unit (AGU) within the starch (mole cationic groups / mole AGU).

[0073] The cationic starch may have a weight average molecular above 500,000 g / mol; 1,000,000 g / mol; more than 5,000,000 g / mol. The skilled person is aware that there are techniques present in the art to measure a weight average molecular weight.

[0074] The cationic starch guarantees that the applied coating composition remains on the surface of the paper and prevents and / or reduces impregnation of the coating composition within the paper.

[0075] Examples of the cationic starch may be commercially available such as Cargill product C*bond 17525.

[0076] The coating composition may have a Brookfield viscosity at 40 °C of from 50 to 5000 mPa.s, preferably from 100 to 3000 mPa.s, more preferably from 200 to 2000 mPa.s, even more preferably from 500 to 1500 mPa.s, most preferably from 750 to 1250 mPa.s.

[0077] The coating composition is preferably an aqueous coating composition.PT-2134-WO-PCT

[0078] A second aspect of the invention is providing a coating composition for a paper substrate, preferably for paper food packaging, comprising a) the plasticizer is in amount of from 15 to 35 wt.%, preferably from 20 to 30 wt.%, more preferably from 22 to 28 wt.% on total amount of the coating composition; b) the synthetic polymer is an amount from 0.1 to 4 wt.%, preferably from 0.5 to 3 wt.%, more preferably from 0.8 to 2 wt.% on total amount of the coating composition; c) the anionic starch is in an amount of from 2 to 18 wt.%, preferably from 5 to 15 wt.%, more preferably from 8 to 12 wt.% on total amount of the coating composition; d) the pectin is in amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; e) the cationic starch is in an amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; and / or f) the water is in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.

[0079] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect of the invention apply mutatis mutandis to the coating composition as explained under the second aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch, the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the coating composition according to the second aspect of the invention.Process

[0080] A third aspect of the invention is providing a process for preparing the coating composition as defined under the first aspect and / or the second aspect of the invention comprising the following steps: a) Preparing a mixture of water, the cationic starch and the anionic starch; b) Heating the mixture obtained in step a) to a temperature of from 105 to 130 °C, preferably from 110 to 125 °C for 1 to 10 minutes, preferably about 5 minutes; c) Lowering the temperature from 70 to 95 °C, preferably from 75 to 85 °C, for 1 to 30 minutes, preferably about 15 minutes;PT-2134-WO-PCT d) Adding the pectin to the mixture obtained in step c) and stirring for 1 to 30 minutes, preferably about 15 minutes; e) Lowering the temperature to below 50 °C, preferably below 45 °C, more preferably below 40 °C; f) Adding the synthetic polymer and the plasticizer to the mixture obtained in step e) and stirring for 1 to 30 minutes, preferably about 15 minutes, to afford the coating composition.

[0081] The heating step b) may occur under increased pressure, such as from 1 bar to 10 bar, preferably from 2 to 8 bar, more preferably from 4 to 6 bar.

[0082] The temperature in step e) may be lowered to from 25 to 45 °C, preferably from to 30 to 40 °C, more preferably from 32 to 38 °C.

[0083] As appreciated by the skilled person there are starch products available which do not require a cooking step, but dissolve into water simply by mixing them with water without additional heat treatment. In this case the process for preparing the coating composition comprises the following steps: i) Preparing a mixture of water, the plasticizer, the synthetic polymer, the anionic starch, the pectin and the cationic starch; ii) Stirring the mixture obtained in step i) to afford the coating composition.Alternatively, the process for preparing the coating composition may comprise the following steps: i) Preparing a dry mixture of the plasticizer, the synthetic polymer, the anionic starch, the pectin and the cationic starch; ii) Adding water to the dry mixture of step i); and iii) Stirring the mixture obtained in step ii) to afford the coating composition.

[0084] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect and / or the second aspect of the invention apply mutatis mutandis to the process as explained under the third aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch, the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the process according to the third aspect of the invention.PT-2134-WO-PCTKit

[0085] A fourth aspect of the invention is providing a kit for preparing the coating composition for paper as defined under the first and / or the second aspect of the invention comprising: i) the plasticizer as defined in the present invention, ii) the synthetic polymer as defined in the present invention, iii) the anionic starch as defined in the present invention, iv) the pectin as defined in the present invention, v) the cationic starch as defined in the present invention, vi) optionally water, and vii) a set of instructions for manufacturing the coating composition using the plasticizer, the synthetic polymer, the cationic starch, the pectin and the anionic starch.

[0086] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect and the second aspect of the invention apply mutatis mutandis to the kit as explained under the fourth aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch, the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the kit according to the fourth aspect of the invention.Process for coating paper substrate

[0087] A fifth aspect of the invention is providing a process for coating a paper substrate by treating a paper substrate with the coating composition as defined under the first and / or second aspect of the invention. The process may comprise the steps of treating the paper substrate with the coating composition followed by drying of the paper substrate to afford the coated paper substrate. The coated paper substrate may be dried at room temperature or with an IR dryer. Optionally, the paper substrate may be calendered before the coating composition is applied.

[0088] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect and the second aspect of the invention apply mutatis mutandis to the process as explained under the fifth aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch,PT-2134-WO-PCT the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the process according to the fifth aspect of the invention.

[0089] For purposes of the present disclosure, the terms "paper substrate" refers to sheet materials of paper or paper product of any thickness, including, for example, single sheet paper, paperboard, cardboard and corrugated board.

[0090] The paper substrate may have a weight basis of from 20 g / m2to 40 g / m2, preferably from 25 g / m2to 35 g / 2m, more preferably from 28 g / m2to 32 g / m2. Alternatively, the paper substrate may have a weight basis of from 46 g / m2to 75 g / m2; or from 48 g / m2to 70 g / m2. Alternatively, the paper substrate may have a weight basis of from 76 g / m2to 100 g / m2; or wherein the paper has a weight basis of from 80 g / m2to 90 g / m2. Alternatively, the paper substrate may have a weight basis of from 100 g / m2to 400 g / m2; or wherein the paper substrate may have a weight basis of from 150 g / m2to 350 g / m2; or wherein the paper substrate may have a weight basis of from 180 g / m2to 300 g / m2.

[0091] The amount of coating composition to be applied to any given substrate is in part dependent on the surface characteristics of the substrates. Substrate materials that are very rough require more coating composition to achieve desired grease resistance properties than smooth substrates. Likewise, substrate materials that are very porous require more coating composition to achieve desired grease resistance properties than non-porous substrates. Preferably, the substrate is coated by applying the coating composition to the substrate in a single application. Alternatively, the substrate is coated by applying the coating composition to the substrate in a plurality of applications, i.e. as a plurality of layers. Alternatively, the substrate is coated by applying the coating composition to the substrate in two applications, i.e. as two layers. Coating the substrates with two or more layers may be beneficial for providing complete and continuous coating on the substrate.

[0092] The coating composition as described herein can be applied to the paper substrate by any suitable known coating technique, such as, for example, air knife coating, rod coating, bar coating, wire bar coating, spray coating, brush coating, cast coating, flexible blade coating, gravure coating, jet applicator coating, extrusion coating, short dwell coating, slide hopper coating, curtain coating, flexographic coating, size-press coating, gate roll coating, reverse roll coating and transfer roll coating. The coating composition may be applied as a single coat to a major surface of the paper substrate or the coating composition may be applied a plurality of times to a major surface of the paper substrate. The coating composition may bePT-2134-WO-PCT also applied as a single coat to both sides (i.e. both major surfaces) of the paper substrate or the coating composition may be applied a plurality of times to both sides (i.e. both major surfaces) of the paper substrate.Paper substrate

[0093] A sixth aspect of the invention is providing the paper substrate obtainable and / or obtained by the process as defined under the fifth aspect of the invention. Alternatively, a paper substrate is provided coated with the coating composition as defined in the present invention.

[0094] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect and the second aspect of the invention, and the process as defined under the fifth aspect apply mutatis mutandis to the paper substrate as explained under the sixth aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch, the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the paper substrate according to the sixth aspect of the invention.

[0095] Preferably, said paper substrate is coated with the coating composition as defined in the present invention.

[0096] For purposes of the present disclosure, grease resistance of the coated paper substrate is measured under a Grease Resistance Test to determine the observed Grease Resistance Kit Rating in accordance with test methodology of TAPPI T559 Kit Test using a 3M Grease Resistance Kit - commonly known as the Kit test. Preferably, the coated paper exhibits a Grease Resistance Kit Rating of from 5 to 12, more preferably from 6 to 12, even more preferably from 7 to 12, even more preferably from 8 to 12, even more preferably from 9 to 12, even more preferably from 10 to 12, even more preferably from 11 to 12, most preferably 12.

[0097] The coated paper substrate is provided with the coating composition at a coating weight of from 1 g / m2to 15 g / m2, preferably from 1 g / m2to 10 g / m2, more preferably from 2 g / m2to 8 g / m2, even more preferably from 3 to 7 g / m2, most preferably from 4 g / m2to 6 g / m2.

[0098] As a particular advantage, the present compositions may be formulated to be substantially free of intentionally added fluorine containing components, such as perfluorinated surfactants.PT-2134-WO-PCT

[0099] For purposes of the present disclosure, flexibility characteristics of the coating composition is evaluated by coating the coating composition on a paper substrate. This sample is evaluated under the Grease Resistance Test as described above, but in two measurements. In the first measurement, the Grease Resistance Test is carried out as described above on a coated surface of the sample that has never been folded to determine that the Initial Grease Resistance Kit Rating meets the desired performance standard for the coating. In the second measurement, the sample is creased and folded, and the Grease Resistance Test is carried out as described above at the location of the fold to determine the Fold Grease Resistance Kit Rating.

[0100] A coating is deemed to be flexible if the sample exhibits an Initial Grease Resistance Kit Rating of at least 5, and the sample exhibits a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below 5. The coating composition may exhibit a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below 6, or a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below7, or a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below8. It will be understood that, for example, in order to achieve a fold Grease Resistance Kit Rating of 8, the Initial Grease Resistance Kit Rating must be at least 8.

[0101] The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 4 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 3 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 2 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 1 Grease Resistance Kit Rating unit.

[0102] For purposes of the present disclosure, flexibility of a coated paper substrate is measured by conducting the above Coating Flexibility test on the coated paper substrate to be prepared, whereby a coating composition is applied to a paper substrate to be used in product production.

[0103] The flexibility of the coated product as determined by the fold and grease challenge (the “Product Coating Flexibility”) may be such that the Fold Grease Resistance Kit Rating does not drop below 5. The coated product may exhibit a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below 6, or a Coating Flexibility such thatPT-2134-WO-PCT the Fold Grease Resistance Kit Rating does not drop below 7, or a Coating Flexibility such that the Fold Grease Resistance Kit Rating does not drop below 8.

[0104] The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 4 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 3 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 2 Grease Resistance Kit Rating units. The difference between the Initial Grease Resistance Kit Rating and the Fold Grease Resistance Kit Rating may be less than 1 Grease Resistance Kit Rating unit.Use

[0105] A seventh aspect of the invention is providing a use of the coating composition as defined under the first and / or second aspect of the invention to improve the grease, oil and / or wax resistance of a paper substrate, preferably a paper food packaging.

[0106] This improved grease resistance test of the coated paper is preferably demonstrated by the Grease Resistance Kit Rating in accordance with test methodology of TAPPI T559 Kit Test using a 3M Grease Resistance Kit. Preferably, the use of the coating composition improves the grease, oil and / or wax resistance of the paper substrate to a Grease Resistance Kit Rating of from 5 to 12, more preferably from 6 to 12, even more preferably from 7 to 12, even more preferably from 8 to 12, even more preferably from 9 to 12, even more preferably from 10 to 12, even more preferably from 11 to 12, most preferably 12.

[0107] As appreciated by the skilled person all features related to the coating composition as explained under the first aspect and the second aspect of the invention apply mutatis mutandis to the use as explained under the seventh aspect of the invention. For example, all features related to the amount and identity of the plasticizer, the cationic starch, the synthetic polymer, the pectin and the water explained in the context of the first aspect of the invention are equally applicable the use according to the seventh aspect of the invention.

[0108] Although certain aspects of the invention have been described, the scope of the appended claims is not intended to be limited solely to these specific aspects. The claims are to be construed literally, purposively, and / or to encompass equivalents. The scope of the presentPT-2134-WO-PCT invention is defined by the appended claims. One or more of the objects of the invention are achieved by the appended claims.EXAMPLEExample 1 (EXI): coating composition

[0109] Water (3.75 kg), C Stretch06392 (1.18 kg; n-OSA starch), and C*bond 17525 (0.09 kg; cationic starch) were mixed in a reactor pilot. The mixture was stirred at 120 °C and 4 bar for 5 minutes. The temperature of the mixture was reduced to 80 °C, Pectin OSS30 (0.09 kg; pectin) was added and the mixture was stirred for 15 minutes. The resulting mixture was further cooled to 35 °C and BaripelG3030 (0.23 kg; acrylic polymer) and C*icoat 41175 (4.65 kg; hydrolysed starch) were added, the mixture was stirred for 15 minutes to afford the resulting coating composition.Example 2 (EX2): coating composition without acrylic polymer

[0110] Water (3.75 kg), C Stretch06392 (1.18 kg; n-OSA starch), and C*bond 17525 (0.09 kg; cationic starch) were mixed in a reactor pilot. The mixture was stirred at 120 °C and 4 bar for 5 minutes. The temperature of the mixture was reduced to 80 °C, Pectina OSS30 (0.09 kg; pectin) was added and the mixture was stirred for 15 minutes. The resulting mixture was further cooled to 35 °C and C*icoat 41175 (4.88 kg; hydrolysed starch) was added, the mixture was stirred for 15 minutes to afford the resulting coating composition.Example 3 (EX3): coating composition without cationic starch

[0111] Water (3.75 kg) and C Stretch06392 (1.27 kg; n-OSA starch) were mixed in a reactor pilot. The mixture was stirred at 120 °C and 4 bar for 5 minutes. The temperature of the mixture was reduced to 80 °C, Pectina OSS30 (0.09 kg; pectin) was added and the mixture was stirred for 15 minutes. The resulting mixture was further cooled to 35 °C and BaripelG3030 (0.23 kg; acrylic polymer) and C*icoat 41175 (4.65 kg; hydrolysed starch) were added, the mixture was stirred for 15 minutes to afford the resulting coating composition.Example 4: coated paperThe coating composition of EXI, EX2 and EX3 were applied (amount applied = 4.5 g / m2) on an uncoated paper (paper grammage = 30.3 g / m2) in a single coating step with a rod lab coater at the same dry substances content level 36% without further additives. The samples were driedPT-2134-WO-PCT on the IR dryer. The improved grease resistance test of the coated paper is demonstrated by the Grease Resistance Kit Rating in accordance with test methodology of TAPPI T559 Kit Test.Table 1 : Kit oil test for paper coated with EXI, EX2 or EX3

[0090] In particular, the paper coated with the coating composition EXI exhibits superior oil and grease resistance characteristics as compared to paper coated with EX2 or EX3.

Claims

PT-2134-WO-PCTCLAIMS1. A coating composition for a paper substrate, preferably for paper food packaging, comprising a) A plasticizer selected from the list consisting of hydrolysed starch, sucrose, hydrolysed cellulose, glucose, glycol, glycerol, sorbitol, maltitol and combinations thereof in amount of from 50 to 80 wt.% on total dry solids, b) A synthetic polymer selected from acrylic polymer, polyvinyl alcohol, polyamine, polyacrylamides, polyamides, styrene-butadiene rubber, and combinations thereof in an amount of from 0.5 to 10 wt.% on total dry solids, c) Anionic starch in an amount of from 10 to 45 wt.% on total dry solids, d) Pectin in an amount of from 0.1 to 10 wt.% on total dry solids, e) Cationic starch in an amount of from 0.1 to 10 wt.% on total dry solids, and f) Water.

2. Coating composition according to claim 1, wherein a) the plasticizer is in amount of from 55 to 75 wt.%, preferably from 60 to 70 wt.%, more preferably from 62 to 68 wt.% on total dry solids; b) the synthetic polymer is in an amount of from 1 to 8 wt.%, preferably from 1.5 to 6 wt.%, more preferably from 2 to 5 wt.% on total dry solids; c) the anionic starch is in an amount of from 15 to 40 wt.%, preferably from 20 to 35 wt.%, more preferably from 25 to 30 wt.% on total dry solids; d) the pectin is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids; and / or e) the cationic starch is in an amount of from 0.2 to 8 wt.%, preferably from 0.5 to 6 wt.%, more preferably from 1 to 4 wt.% on total dry solids.

3. Coating composition according to claim 1 or claim 2, wherein the plasticizer is a hydrolysed starch, preferably the hydrolysed starch comprises or consists of glucose syrup, fructose syrup, maltodextrin, dextrin or any combination thereof preferably glucose syrup, maltodextrin, or any combination thereof.PT-2134-WO-PCT4. Coating composition according to any one of claims 1-3, wherein the synthetic polymer is an acrylic polymer, preferably the acrylic polymer is an (meth)acrylic copolymer, a styrene / (meth)acrylic copolymer or a combination thereof.

5. Coating composition according to any one of claims 1-4, wherein the anionic starch is an anionic anhydride modified starch, preferably the anionic anhydride modified starch is an alkyl or alkenyl succinic anhydride modified starch, preferably octenyl succinic anhydride modified starch.

6. Coating composition according to any one of claims 1-5, wherein the pectin is high- methoxyl pectin, preferably wherein the degree of methoxylation is greater than or equal to 50%.

7. Coating composition according to any one of claims 1-6, wherein the cationic starch is an ammonium, sulfonium or phosphonium substituted cationic starch.

8. Coating composition according to any one of claims 1-7, wherein a) the plasticizer is in amount of from 15 to 35 wt.%, preferably from 20 to 30 wt.%, more preferably from 22 to 28 wt.% on total amount of the coating composition; b) the synthetic polymer is an amount from 0.1 to 4 wt.%, preferably from 0.5 to 3 wt.%, more preferably from 0.8 to 2 wt.% on total amount of the coating composition; c) the anionic starch is in an amount of from 2 to 18 wt.%, preferably from 5 to 15 wt.%, more preferably from 8 to 12 wt.% on total amount of the coating composition; d) the pectin is in amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; e) the cationic starch is in an amount of from 0.1 to 1.5 wt.%, preferably from 0.2 to 1.2 wt.%, more preferably from 0.3 to 1 wt.% on total amount of the coating composition; and / or f) the water is in amount of from 40 to 80 wt.%, preferably from 50 to 70 wt.%, more preferably from 55 to 65 wt.% on total amount of the coating composition.PT-2134-WO-PCT9. A process for preparing the coating composition according to any one of claims 1-8 comprising the following steps: a) Preparing a mixture of water, the cationic starch as defined in any one of claims 1- 8 and the anionic starch as defined in any one of claims 1-8; b) Heating the mixture obtained in step a) to a temperature of from 105 to 120 °C for 1 - 10 minutes, preferably about 5 minutes; c) Lowering the temperature to 70 to 95 °C for 1 to 30 minutes, preferably about 15 minutes; d) Adding the pectin as defined in any one of claims 1-8 to the mixture obtained in step c) and stirring for 1 to 30 minutes, preferably about 15 minutes; e) Lowering the temperature to below 50 °C, preferably below 45 °C; and f) Adding the synthetic polymer as defined any one of claims 1-8 and the plasticizer as defined any one of claims 1-8 to mixture obtained in step e) and stirring for 1 to 30 minutes, preferably about 15 minutes, to afford the coating composition.

10. A kit for preparing the coating composition for a paper substrate according to any one of claims 1-8 comprising i) Plasticizer as defined in any one of claims 1-8, ii) Synthetic polymer as defined in any one of claims 1-8, iii) Cationic starch as defined in any one of claims 1-8, iv) Pectin as defined in any one of claims 1-8, v) Anionic starch as defined in any one of claims 1-8, and vi) a set of instructions for manufacturing the coating composition using the plasticizer, the synthetic polymer, the cationic starch, the pectin and the anionic starch.

11. A process for coating a paper substrate by treating the paper substrate with the coating composition according to any one of claims 1-8 followed by drying.

12. Paper substrate obtainable by the process according to claim 11.

13. A paper substrate coated with the coating composition according to any one of claims 1-8.PT-2134-WO-PCT14. Paper substrate according to claim 12 or claim 13 having a Grease Resistance KitRating of at least KIT6, preferably at least KIT8, more preferably at least KIT9.

15. Use of the coating composition according to any one of claims 1-8 to improve the oil and / or grease resistance in a food packaging, preferably a paper food packaging.

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