Alkyd emulsion neutralized with lithium and sodium salts

Abstract

The present invention relates to an alkyd emulsion comprising an alkyd resin neutralized with lithium and sodium salts. The invention also relates to a method for preparing the alkyd emulsion and to the use thereof for obtaining a coating, in particular a decorative or industrial coating.

Description

[0001] DESCRIPTION

[0002] Title: Alkyd emulsion neutralized by lithium and sodium salts

[0003] TECHNICAL FIELD

[0004] The present invention relates to an alkyd emulsion comprising an alkyd resin neutralized by lithium and sodium salts. The invention also covers a process for preparing the alkyd emulsion and its use for obtaining a coating, in particular a decorative or industrial coating.

[0005] PRIOR ART

[0006] Polyester resins are made by reacting polyacids and polyols. Polyester resins can be modified by adding a fatty component, such as an oil or fatty acid, to form a special type of polyester resin: alkyd resins. Alkyd resins have been used for over 50 years to form coatings, including decorative and industrial paints.

[0007] The presence of a fatty component in alkyd resins gives flexibility and gloss to the resulting coating. When the fatty component contains unsaturations, alkyds can dry by autoxidation (siccativation).

[0008] Alkyd resins in organic solvent medium, otherwise known as solvent-based alkyd resins, have long been known to those skilled in the art, generally used in coatings and decorative and industrial paint formulations. To address issues of ease of use, odor, and toxicity related to the use of volatile organic compounds (VOCs), alkyd emulsions have been developed. Alkyd emulsions, also known as post-emulsified alkyd resins, can be obtained by emulsifying an alkyd resin by adding a surfactant and water. Alkyd emulsions can advantageously have a high bio-based renewable carbon (BRC) content due to the use of bio-sourced acids and / or alcohols such as rosin, vegetable oil fatty acids, vegetable diacids, glycerol, and polyglycerols.

[0009] To improve the storage stability of bio-based alkyd emulsions, it is known to neutralize the acid functions of the alkyd resin, in particular with lithium salts. However, alkyd resins neutralized by lithium salts contain residual lithium hydroxide which is toxic and will probably be classified as CMR in the near future. Surprisingly, the Applicant discovered that the sequential use of sodium hydroxide and lithium hydroxide to neutralize the acid functions of the alkyd made it possible to obtain a stable emulsion while maintaining acceptable properties in terms of development of hardness, gloss, adhesion to the substrate, flexibility, abrasion resistance, resistance to self-adhesion (blocking), mechanical strength, water resistance and resistance to yellowing.This thus leads to a solution that is friendly to humans and the environment due to the absence of organic solvents, residual lithium hydroxide and drying agents, but also due to the choice of essential raw materials, insofar as a high proportion of these raw materials can be of renewable and sustainable origin. Thus, the alkyd emulsion according to the invention can contain a proportion of renewable raw materials of 90-100% by weight, on the overall composition of the resin, while having a competitive cost price.

[0010] SUMMARY OF THE INVENTION

[0011] The subject matter of the present invention relates to an alkyd emulsion comprising an alkyd resin, the alkyd resin being based on an acid component A and an alcohol component B, the alkyd resin comprising lithium carboxylate groups and sodium carboxylate groups.

[0012] The invention also relates to a process for preparing an emulsion according to the invention, the process comprising the following steps: i) preparation of an alkyd resin in the molten state, the alkyd resin being based on an acid component A and an alcohol component B; ii) addition of a surfactant component T and water; iii) partial neutralization of the acidity of the reaction mixture by addition of lithium hydroxide; iv) neutralization of at least part of the residual acidity of the reaction mixture by addition of sodium hydroxide; v) emulsification by phase inversion; vi) optionally adjustment of the dry extract of the alkyd emulsion.

[0013] The invention also relates to a composition comprising an alkyd emulsion according to the invention.

[0014] The invention also relates to the use of the alkyd emulsion according to the invention, as a binder for obtaining a coating, an adhesive or a sealant, in particular for obtaining a coating, more particularly for obtaining a film, a paint, a varnish, a lacquer, a stain, an adhesion primer or an ink. The invention also relates to a coating, an adhesive or a sealant obtained by applying and drying the composition according to the invention.

[0015] DETAILED DESCRIPTION

[0016] Definitions

[0017] In this application, the terms "includes a" and "includes a" mean respectively "includes one or more" and "includes one or more".

[0018] Unless otherwise stated, percentages by weight in a compound or composition are expressed relative to the weight of the compound or composition.

[0019] For the purposes of the present invention, an ethylenically unsaturated group or compound is a group or compound containing a polymerizable carbon-carbon double bond.

[0020] For the purposes of the present invention, a polymerizable carbon-carbon double bond is a carbon-carbon double bond that can react with another carbon-carbon double bond in a polymerization reaction. A polymerizable carbon-carbon double bond is generally comprised in a group selected from acrylate (including cyanoacrylate), methacrylate, acrylamide, methacrylamide, styrene, maleate, fumarate, itaconate, allyl, propenyl, vinyl and combinations thereof, preferably selected from acrylate, methacrylate, allyl and vinyl. Carbon-carbon double bonds of an aromatic ring are not considered to be polymerizable carbon-carbon double bonds.

[0021] For the purposes of the present invention, an alkyl group is a monovalent saturated acyclic group of formula -C n H2n+i. An alkyl can be straight or branched. A C1-C6 alkyl means an alkyl containing 1 to 6 carbon atoms.

[0022] For the purposes of the present invention, an alkenyl group is a monovalent acyclic group having one or more C=C double bonds. An alkenyl can be linear or branched.

[0023] For the purposes of the present invention, an alkoxy group is a group of formula -O-alkyl.

[0024] For the purposes of the present invention, an aryl group is a group containing at least one aromatic ring. An aryl may contain a single aromatic ring or several rings, at least one of which is aromatic. An aromatic ring corresponds to a ring complying with Hückel's rule. Examples of aryl groups are phenyl, biphenyl, naphthyl and anthracenyl. The aryl groups of the invention preferably comprise from 6 to 12 carbon atoms. Even more preferably, the aryl group of the invention is a phenyl group. For the purposes of the present invention, an alkylaryl group is a group of formula -A-aryl, in which A is an alkylene. Preferably, an alkylaryl is a group of formula -CR2R3-Ph and R2 and R3 are independently H or Me, more preferably a group of formula -CH(CH3)-Ph.

[0025] For the purposes of the present invention, an alkylene group is a divalent aliphatic radical derived from an alkane of formula C mH2m+2 with m = 2 to 50, removing a hydrogen atom at each point of attachment of the radical. An alkylene can be linear or branched. A C2-C4 alkylene means an alkylene comprising 2 to 4 carbon atoms.

[0026] For the purposes of the present invention, an oxyalkylene group is a group of formula -OA- in which A is an alkylene.

[0027] For the purposes of the present invention, a polyoxyalkylene group is a group of formula -O-[AO] n - wherein each A is independently C2-C4 alkylene, preferably ethylene or propylene; and n ranges from 1 to 100, from 2 to 60, from 3 to 50, from 4 to 40 or from 5 to 30.

[0028] For the purposes of the present invention, an aliphatic group or compound is a non-aromatic acyclic group or compound. It may be linear or branched, saturated or unsaturated, substituted or unsubstituted. It may comprise one or more bonds / functions, for example chosen from ether, ester, amide, urethane, urea and mixtures thereof.

[0029] For the purposes of the present invention, a cycloaliphatic group or compound is a non-aromatic group or compound comprising a ring. It may be substituted or unsubstituted. It may comprise one or more bonds / functions as defined for the term "aliphatic".

[0030] For the purposes of the present invention, an aromatic group or compound is a group or compound comprising an aromatic ring, i.e. complying with Hückel's rule of aromaticity, in particular a group or compound comprising a phenyl group. It may be substituted or unsubstituted. It may comprise one or more bonds / functions as defined for the term "aliphatic".

[0031] For the purposes of the present invention, a saturated group or compound means a group or compound which does not comprise a carbon-carbon double or triple bond.

[0032] For the purposes of the present invention, an unsaturated group or compound means a group or compound which comprises a carbon-carbon double or triple bond, in particular a carbon-carbon double bond.

[0033] For the purposes of the present invention, a substituted group or compound is a group or compound in which one or more hydrogen atoms have been replaced by a group or function independently selected from alkyl, hydroxyl (-OH), alkoxy, halogen (Br, Cl, I), cyano (-CN), isocyanate (-NCO), oxo (=O), amine (-NR2), carboxylic acid (-COOH), ester (-COOR'), anhydride (-CO-O-COR'), a sulfonyl group (- S(=O)2OR), a phosphonyl group (-P(=O)(OR”)2), a sulfated group (-OS(=O)2OR”) and a phosphate group (-OP(=O)(OR”)2), each R being independently H or alkyl, each R' being independently alkyl and each R” being independently a hydrogen atom, a metal salt or a hydrocarbyl chain.

[0034] Alkyd emulsion

[0035] The invention firstly relates to an alkyd emulsion comprising an alkyd resin. The alkyd emulsion may further comprise at least one surfactant component T and water.

[0036] An emulsion may in particular correspond to a liquid organic phase (discontinuous phase) dispersed in the form of droplets in an aqueous phase (continuous phase), the droplets being optionally stabilized by a surfactant. According to a particular embodiment, the alkyd emulsion is not in the form of a dispersion of a solid or semi-solid organic phase in an aqueous phase, in other words it is not in the form of a colloidal suspension or a latex.

[0037] The aqueous phase may in particular be a liquid comprising water. This liquid may further comprise a solvent other than water, such as, for example, butyl glycol.

[0038] According to one embodiment, the alkyd emulsion comprises less than 10%, in particular less than 5%, more particularly less than 1%, more particularly still less than 0.1%, by weight of solvent other than water relative to the weight of the emulsion. Thus, the alkyd emulsion has a low content of volatile organic compounds (VOCs), i.e. less than 10%, in particular less than 5%, more particularly still less than 1%, more particularly still less than 0.1%, by weight of VOCs relative to the weight of the emulsion.

[0039] The liquid organic phase may in particular comprise an alkyd resin as described below. According to a particular embodiment, the alkyd resin is not self-emulsifiable, that is to say that it does not contain a sufficient quantity of ionizable functional groups to spontaneously form an emulsion after addition of water with stirring. In other words, a surfactant is preferably added to stabilize the alkyd emulsion according to the invention.

[0040] The surfactant may in particular be as described below. According to one embodiment, the alkyd emulsion has a solids content (also called dry extract) of 35 to 65%, in particular 40 to 60%, more particularly 45 to 55% by weight. The dry extract can be measured by the ISO 3251:2008 method.

[0041] The alkyd emulsion can have a pH of 7 to 9, particularly 7.5 to 8.5.

[0042] The viscosity of the alkyd emulsion may in particular range from 1 to 1000 mPa s, in particular 2 to 500 mPa s, more particularly 5 to 100 mPa.s. The viscosity may be measured at 23°C according to the measuring method described below.

[0043] The alkyd emulsion may in particular have an average particle size of 50 to 1000 nm, in particular 75 to 500 nm, more particularly 100 to 300 nm. The average particle size may correspond to the volume average size measured by laser granulometry.

[0044] The alkyd emulsion may in particular have a free lithium hydroxide content which is less than 100 ppm, preferably less than 50 ppm, preferably less than 10 ppm.

[0045] Alkyd resin

[0046] The alkyd emulsion according to the invention comprises an alkyd resin.

[0047] Alkyd resin is based on an acid component A and an alcohol component B. In other words, alkyd resin is obtained by polycondensation of an acid component A and an alcohol component B.

[0048] Acid component A comprises at least one acid. Acid component A may comprise a mixture of acids. Preferably, acid component A consists of all of the acids used to prepare the alkyd resin.

[0049] The alcohol component B comprises at least one alcohol. The alcohol component B may comprise a mixture of alcohols. Preferably, the alcohol component B consists of all of the alcohols used to prepare the alkyd resin.

[0050] For the purposes of the present invention, the term "acid" means a compound comprising at least one carboxylic acid function (-COOH) or a function capable of generating a carboxylic acid function in situ (in particular by hydrolysis). The term "acid" therefore includes acid derivatives such as anhydrides and esters. When the acid contains a single carboxylic acid function (or a single function capable of generating a carboxylic acid function in situ), it is a monoacid. When the acid contains more than one carboxylic acid function (or more than one function capable of generating a carboxylic acid function in situ), it is a polyacid.

[0051] For the purposes of the present invention, the term "alcohol" means a compound comprising at least one hydroxyl function (-OH). When the alcohol contains a single hydroxyl function, it is a monoalcohol. When the alcohol contains more than one hydroxyl function, it is a polyol.

[0052] Component A may in particular represent from 50 to 95%, in particular from 60 to 90%, more particularly from 70 to 80% of the total weight of components A and B. In other words, the alkyd resin comprises from 50 to 95%, in particular from 60 to 90%, more particularly from 70 to 80%, by weight of units derived from an acid relative to the total weight of the alkyd resin.

[0053] Component B may in particular represent from 5 to 50%, in particular from 10 to 40%, more particularly from 20 to 30% of the total weight of components A and B. In other words, the alkyd resin comprises from 5 to 50%, in particular from 10 to 40%, more particularly from 20 to 30%, by weight of units derived from an alcohol relative to the total weight of the alkyd resin.

[0054] In particular, the total weight of components A and B represents the total weight of the alkyd resin.

[0055] The alkyd resin contains lithium carboxylate groups (-COOLi) and sodium carboxylate groups (-COONa). These groups originate in particular from the specific neutralization method used in the process described below.

[0056] The ratio between the number of lithium carboxylate groups and the number of sodium carboxylate groups of the alkyd resin may in particular range from 1 to 50, preferably from 5 to 30, more preferably from 10 to 20. Alternatively, the ratio between the number of lithium carboxylate groups and the number of sodium carboxylate groups of the alkyd resin may range from 1 to 20, preferably from 2 to 15, more preferably from 3 to 10. The ratio between the number of lithium carboxylate groups and the number of sodium carboxylate groups of the alkyd resin may in particular be calculated from the number of moles of LiOH and NaOH introduced during the step of neutralizing the alkyd resin as described in the process described below.

[0057] The alkyd resin can in particular have an oil length of 10 to 60%, in particular 20 to 50%, more particularly 20 to 40%.

[0058] The oil length of an alkyd resin may in particular correspond to the % by weight of fatty component used to obtain the alkyd resin (or the % by weight of units derived from a fatty component) relative to the total weight of the alkyd resin. The fatty component includes in particular all the fatty acids used to prepare the alkyd resin.

[0059] For the purposes of the present invention, the term "fatty acid" means an acid having a fatty chain, i.e. a (non-cyclic) hydrocarbyl chain comprising from 10 to 60, in particular 12 to 55, more particularly 14 to 50, consecutive carbon atoms. A fatty acid may be saturated or unsaturated. A saturated fatty acid is a fatty acid which does not comprise a C=C double bond. An unsaturated fatty acid comprises at least one C=C double bond. A monounsaturated fatty acid contains a single C=C double bond. A polyunsaturated fatty acid contains more than one C=C double bond. The hydrocarbyl chain of the fatty acid may be substituted, in particular by one or more hydroxyl or carbonyl functions.The term "fatty acid" includes fatty acid derivatives, i.e. compounds capable of generating a fatty acid in situ, in particular by hydrolysis, as well as compounds obtained by reaction between several fatty acids (in particular dimerization, trimerization, standolization, estolidation). Fatty acid derivatives include in particular fatty acid esters (in particular fatty acid alkyl esters and triglycerides or oils), stand oils, estolides as well as fatty acid dimers and trimers.

[0060] Component A1 and component A4 as described below are not considered fatty components and therefore do not enter into the calculation of oil length.

[0061] Acid component A may include a rosin component, also referred to as component A1.

[0062] Component A1 comprises at least one rosin. Component A1 may comprise a mixture of rosins. In particular, component A1 consists of all the rosins used to prepare the alkyd resin.

[0063] For the purposes of the present invention, the term "rosin" refers to a resin obtained from resinous trees, particularly conifers, such as pines, cedars, firs, hemlocks, larches, or spruces. Rosin may be produced by heating conifer oleoresin (i.e., gum resin taken from living conifers) to remove water and volatile liquid terpene components, also known as turpentine. Rosin produced with this process may be referred to as gum rosin. Gum rosin generally comprises resin acids and is substantially free of fatty acids. Alternatively, rosin may be produced from the distillation of crude tall oil. Rosin produced with this process may be referred to as tall oil rosin or tall oil pitch and is referenced under the CAS number. [8016-81-7], Crude tall oil is a by-product resulting from the manufacture of paper pulp by the Kraft process.When coniferous wood chips are treated with a mixture of sodium hydroxide and sodium sulfide under warm conditions, the lignin and hemicellulose degrade and dissolve in the liquor, while the cellulose can be recovered as a pulp and then washed. The liquor, which also contains resin acids and fatty acids in the form of sodium carboxylates, can be recovered and concentrated. The foam that forms on the surface of the concentrated liquor, also called kraft soap or rosin soap, can be recovered and acidified under warm conditions with sulfuric acid to provide crude tall oil. The crude tall oil can then be distilled under reduced pressure to provide tall oil rosin as a residual non-volatile fraction. Tall oil rosin generally includes resin acids and tall oil fatty acids (mainly palmitic acid, oleic acid, and linoleic acid).When the rosin includes resin acids and tall oil fatty acids, these are counted in components A2 and A5 to A7 described below.

[0064] The term "rosin" therefore includes gum rosin, tall oil rosin, and rosin derivatives. The composition of rosin varies depending on the resinous tree used and its origin. The term "rosin derivative" refers to rosin that has been modified, for example, by one or more of the following reactions: esterification, hydrogenation of a carbon-carbon double bond, epoxidation of a carbon-carbon double bond, hydroxylation of a carbon-carbon double bond, dehydration, maleinization, dimerization, trimerization, or oligomerization.

[0065] In particular, component A1 may comprise at least one resin acid or one of its derivatives. Component A1 may comprise a mixture of resin acids or derivatives thereof.

[0066] For the purposes of the present invention, a "resin acid", also referred to as "resinous acid" or "rosin acid", denotes a polycyclic compound, in particular a terpenoid, bearing a carboxylic acid group which is derived from resinous trees, in particular conifers. The term "resin acid derivative" means a resin acid which has been modified, for example by one or more of the reactions described above for the modification of rosin.

[0067] Preferably, component A1 comprises at least one resin acid represented by one of the following formulae (A) and (B), or one of its derivatives: [Chem 1] wherein the dotted bonds may be independently selected from single carbon-carbon bonds and double carbon-carbon bonds.

[0068] More preferably, component A1 comprises at least one resin acid chosen from the group consisting of abietic acid, pimaric acid, levopimaric acid, dihydroabietic acid, tetrahydroabietic acid, dehydroabietic acid, palustric acid, neoabietic acid, isopimaric acid, sandaracopimaric acid, their derivatives and their mixtures.

[0069] Component A1 may represent from 0 to 50%, preferably from 5 to 45%, more preferably from 10 to 40%, of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 50%, preferably from 5 to 45%, more preferably from 10 to 40%, by weight of units derived from a rosin relative to the total weight of the alkyd resin.

[0070] The A-acid component may include a conjugated fatty acid component, also called the A2 component.

[0071] Component A2 comprises at least one conjugated fatty acid. Component A2 may comprise a mixture of conjugated fatty acids. In particular, component A2 consists of all of the conjugated fatty acids used to prepare the alkyd resin.

[0072] For the purposes of the present invention, the term "conjugated fatty acid" means a polyunsaturated fatty acid comprising two C=C double bonds separated by a single CC bond. A conjugated fatty acid may in particular result from the isomerization of a polyunsaturated fatty acid (in particular of natural origin, more particularly of plant or animal origin) such as linoleic acid, alpha-linolenic acid, gamma-linoleic acid, stearidonic acid, icosapentaenoic acid, docosahexaenoic acid. A conjugated fatty acid may also result from the dehydration of a hydroxylated unsaturated fatty acid (in particular of natural origin, more particularly of plant origin) such as ricinoleic acid.

[0073] Examples of conjugated fatty acids are 9,11-octadecadienoic acid, 10,12-octadecadienoic acid, 8,10,12-octadecatrienoic acid, 9,11,13-octadecatrienoic acid, 9,11,15-octadecatrienoic acid, 9,13,15-octadecatrienoic acid, 6,9, 11-octadecatrienoic acid, 10,12,14-octadecatrienoic acid, 9, 11, 13,15-octadecatetraenoic acid, 10,12-nonadecadienoic acid, 5,7,9, 14, 17-icosapentaenoic acid, 5,8,10,12,14- icosapentaenoic acid. Preferably, the conjugated fatty acid is 9,11- octadecadienoic acid.

[0074] Component A2 may represent from 0 to 50%, preferably from 5 to 40%, more preferably from 10 to 35% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 50%, preferably from 5 to 40%, more preferably from 10 to 35%, by weight of units derived from a conjugated fatty acid relative to the total weight of the alkyd resin.

[0075] The conjugated fatty acid may in particular be introduced in the form of a mixture of fatty acids comprising one or more conjugated fatty acids as well as one or more fatty acids chosen from a saturated fatty acid, a monounsaturated fatty acid, a non-conjugated polyunsaturated fatty acid, as well as derivatives thereof. Such mixtures may in particular be derived from an oil or fat of natural origin, in particular a vegetable or animal oil, such as castor oil, sunflower oil, linseed oil, soybean oil, tall oil (tallol or "tall oil"), tung oil, chia seed oil, perilla oil, poppy seed oil, cottonseed oil, lesquerella oil, safflower oil, oiticica oil, rapeseed oil, corn oil, calendula oil, hemp oil, fish oil. The oil may in particular be a vegetable oil modified by a dehydration and / or isomerization reaction to generate conjugated double bonds.

[0076] In particular, the conjugated fatty acid may be derived from a modified vegetable oil, preferably chosen from dehydrated castor oil, isomerized sunflower oil, isomerized linseed oil, isomerized soybean oil, more preferably dehydrated castor oil.

[0077] Examples of mixtures comprising a conjugated fatty acid are Nouracid® DE 656, DE 655, DE 554, DE 503, DE 402 or DZ 453 (Dehydrated castor oil fatty acid - available from Oléon); Nouracid® HE 456, HE 306, HE 305, HE 304, HE 303 or HE 301 (Isomerized sunflower oil fatty acid - available from Oléon); Nouracid® LE 805 (Isomerized linseed oil fatty acid - available from Oléon); Nouracid® SE 305 (Isomerized soybean oil fatty acid - available from Oléon); Dedico® 5981 (Dehydrated castor oil fatty acid - available from Croda), Isomergic acid SK, SY or SF (Isomerized vegetable fatty acid - available from Hobum Oleochemicals GmbH), Pamolyn® 300, (Isomerized tall oil fatty acid - available from Eastman).

[0078] Acid component A may comprise a polyacid component, also referred to as component A3. Component A3 comprises at least one polyacid. Component A3 may comprise a mixture of polyacids. In particular, component A3 consists of all the polyacids used to prepare the alkyd resin.

[0079] The polyacid may in particular be unsaturated or saturated, in particular saturated. The polyacid may in particular be chosen from a dicarboxylic acid, a tricarboxylic acid, a monocarboxylic acid dimer, a monocarboxylic acid trimer, a derivative thereof, as well as a mixture thereof. The polyacid may in particular comprise 3 to 54, in particular 4 to 20, more particularly 5 to 15, carbon atoms. According to one embodiment, the polyacid is a saturated or unsaturated polyacid. According to one embodiment, the polyacid is an aliphatic, cycloaliphatic or aromatic polyacid, preferably aromatic.

[0080] The polyacid may in particular have a functionality (number of carboxylic acid or carboxylic acid derivative functions) ranging from 2 to 4, in particular from 2 to 3, more particularly equal to 2.

[0081] Examples of saturated aliphatic polyacids are malonic acid, succinic acid, 2-methylsuccinic acid, 2,2-dimethylsuccinic acid, glutaric acid, 3,3-diethylglutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, citric acid, propane-1,2,3-tricarboxylic acid, a dimer of a saturated C32-C36 fatty acid, a trimer of a saturated C54 fatty acid, and mixtures thereof.

[0082] Examples of unsaturated aliphatic polyacids are itaconic acid, maleic acid, fumaric acid, glutaconic acid, muconic acid, and mixtures thereof.

[0083] An example of a saturated cycloaliphatic polyacid is cyclohexane dicarboxylic acid.

[0084] An example of an unsaturated cycloaliphatic polyacid is tetrahydrophthalic acid.

[0085] Examples of aromatic polyacids are phthalic acid, isophthalic acid, terephthalic acid, naphthalene dicarboxylic acid, trimellitic acid, 2,5-furan dicarboxylic acid and mixtures thereof.

[0086] The polyacid may be a polyacid derivative. Such a derivative may be converted into a polyacid by hydrolysis. Polyacid derivatives include partially or fully esterified forms of the polyacids defined above, including C1-C6 alkyl mono-, di-, and triesters of the polyacids defined above, as well as cyclic anhydrides. The polyacid derivatives may, in particular, comprise 5 to 60, in particular 6 to 25, more particularly 7 to 20, carbon atoms.

[0087] Examples of suitable ester polyacid derivatives are dimethyl malonate, diethyl malonate, dimethyl adipate, dimethyl glutarate, dimethyl succinate.

[0088] The polyacid derivative may in particular be a cyclic anhydride. The cyclic anhydride may be saturated or unsaturated, in particular unsaturated. The cyclic anhydride may be cycloaliphatic or aromatic, in particular aromatic.

[0089] Examples of saturated cyclic anhydrides are succinic anhydride and hexahydrophthalic anhydride. Examples of cycloaliphatic unsaturated anhydrides are maleic anhydride, fumaric anhydride, and tetrahydrophthalic anhydride. An example of an aromatic anhydride is phthalic anhydride.

[0090] According to a preferred embodiment, the polyacid component A3 comprises at least one saturated aliphatic polyacid, in particular sebacic acid, succinic acid and mixtures thereof.

[0091] Component A3 may represent from 0 to 50%, in particular 10 to 45%, more particularly 20 to 40% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 50%, in particular from 10 to 45%, more particularly from 20 to 40% by weight of units derived from a polyacid relative to the total weight of the alkyd resin.

[0092] Acid component A may comprise a non-fatty monoacid component, also referred to as component A4. Component A4 comprises at least one non-fatty monoacid. Component A4 may comprise a mixture of non-fatty monoacids. In particular, component A4 consists of all of the non-fatty monoacids for preparing the alkyd resin.

[0093] For the purposes of the present invention, the term "non-fatty monoacid" means a C2-C9 monoacid, i.e. a monoacid having 2 to 9 carbon atoms.

[0094] The non-fatty monoacid may be an aliphatic, cycloaliphatic or aromatic monoacid, especially aliphatic or aromatic.

[0095] Examples of suitable non-fatty monobasic acids are benzoic acid, tert-butylbenzoic acid, hexahydrobenzoic acid, caproic acid, caprylic acid, 2-ethylhexanoic acid, pentenoic acid, pentadienoic acid, hexenoic acid, hexadienoic acid, heptenoic acid, heptadienoic acid, octenoic acid, octadienoic acid, nonenoic acid, nonadienoic acid, and mixtures thereof.

[0096] According to a particular embodiment, component A4 comprises an aromatic non-fatty monoacid, more particularly benzoic acid.

[0097] According to a particular embodiment, component A4 comprises an unsaturated non-fatty monoacid, more particularly a hexadienoic acid, in particular sorbic acid.

[0098] Component A4 may represent from 0 to 50%, in particular from 5 to 30%, more particularly from 10 to 20% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 50%, in particular from 5 to 30%, more particularly from 10 to 20% by weight of units derived from a non-fatty monoacid relative to the total weight of the alkyd resin.

[0099] Acid component A may comprise a saturated fatty acid component, also referred to as component A5. Component A5 comprises at least one saturated fatty acid. Component A5 may comprise a mixture of saturated fatty acids. In particular, component A5 consists of all of the saturated fatty acids used to prepare the alkyd resin.

[0100] Examples of saturated fatty acids are capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, 9-hydroxy stearic acid, 10-hydroxystearic acid, 12-hydroxystearic acid, icosanoic acid, 14-hydroxyicosanoic acid and mixtures thereof. The saturated fatty acid may be derived from, among other things, palm oil, coconut oil, hydrogenated castor oil, animal fat and mixtures thereof.

[0101] Component A5 may represent from 0 to 20%, in particular from 0 to 10%, more particularly from 0 to 5% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 20%, in particular from 0 to 10%, more particularly from 0 to 5%, by weight of units derived from a saturated fatty acid relative to the total weight of the alkyd resin.

[0102] The acid component A may comprise a monounsaturated fatty acid component, also referred to as the A6 component. The A6 component comprises at least one monounsaturated fatty acid. The A6 component may comprise a mixture of monounsaturated fatty acids. In particular, the A6 component consists of all of the monounsaturated fatty acids used to prepare the alkyd resin. Examples of monounsaturated fatty acids are myristoleic acid, palmitoleic acid, sapienic acid, oleic acid, gadoleic acid, ricinoleic acid (12-hydroxy-9-octadecenoic acid), elaidic acid, trans-vaccenic acid, erucic acid, nervonic acid, brassidic acid, lesquerolic acid (14-hydroxy-11-icosenoic acid), and mixtures thereof.

[0103] The monounsaturated fatty acid can in particular come from a vegetable oil as described above.

[0104] Component A6 may represent from 0 to 20%, in particular from 1 to 10%, more particularly from 2 to 8% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 20%, in particular from 1 to 10%, more particularly from 2 to 8%, by weight of units derived from a monounsaturated fatty acid relative to the total weight of the alkyd resin.

[0105] Acid component A may comprise a non-conjugated polyunsaturated fatty acid component, also referred to as component A7. Component A7 comprises at least one non-conjugated polyunsaturated fatty acid. Component A7 may comprise a mixture of non-conjugated polyunsaturated fatty acids. In particular, component A7 consists of all of the non-conjugated polyunsaturated fatty acids used to prepare the alkyd resin.

[0106] Examples of non-conjugated polyunsaturated fatty acids are omega-3 and omega-6 fatty acids, such as, in particular, 7,10,13-hexadecatrienoic acid, 9,12,15-octadecatrienoic acid, 6,9,12,15-octadecatrienoic acid, 11,14,17- icosatrienoic acid, 8,11,14,17- icosatetraenoic acid, 5,8,11,14,17- icosapentaenoic acid, 6,9,12,15,18- heneicosapentaenoic acid, 7,10,13,16,19- docosapentaenoic acid, 4,7,10,13,16,19-docosahexaenoic acid, 9, 12,15,18,21-tetracosapentaenoic acid, 6,9,12,15,18,21-tetracosahexaenoic acid, 9,12-octadecadienoic acid, 6,9,12-octadecatrienoic acid, 11,14-icosadienoic acid, 8,11,14-icosatrienoic acid, 5, 8, 11,14-icosatetraenoic acid, 13,16-docosadienoic acid, 7,10,13,16-docosatetraenoic acid, 4,7,10,13,16-docosapentaenoic acid, acid 9,12,15,18-tetracosatetraenoic acid, 6, 9, 12, 15,18-tetracosapentaenoic acid, and mixtures thereof.

[0107] The polyunsaturated fatty acid may in particular be derived from a vegetable oil as described for the conjugated fatty acid (preferably without modification such as isomerization). Preferably, the non-conjugated polyunsaturated fatty acid is derived from a vegetable oil chosen from soybean oil, sunflower oil or tall oil (tall oil). Component A7 may represent from 0 to 50%, in particular from 1 to 30%, more particularly from 5 to 20% of the total weight of components A and B. In other words, the alkyd resin may comprise from 0 to 50%, in particular from 1 to 30%, more particularly from 5 to 20%, by weight of units derived from a non-conjugated polyunsaturated fatty acid relative to the total weight of the alkyd resin.

[0108] Components A1, A2, A3, A4, A5, A6 and A7 are distinct from each other.

[0109] Alkyd resin is based on an alcohol component B.

[0110] The alcohol component B may comprise a polyol component B1. Component B1 comprises at least one polyol. Component B1 may comprise a mixture of polyols. In particular, component B1 consists of all the polyols used to prepare the alkyd resin.

[0111] Component B1 may in particular have a functionality (number of hydroxyl functions) ranging from 2 to 6, in particular from 2.5 to 5.5, more particularly from 3 to 5. When component B1 comprises a mixture of polyols, the functionality of component B1 corresponds to the average functionality of the polyol component, also called f Bi .

[0112] The average functionality f Bi of a polyol component comprising a mixture of n polyols can in particular be determined with the following equation:

[0113] [Math 1] where xi is the mole fraction of polyol i (corresponding to the number of moles of polyol i divided by the total number of moles of polyols in component B1); fi is the functionality of polyol i (corresponding to the number of hydroxyl functions of polyol i).

[0114] Component B1 may in particular comprise an aliphatic, cycloaliphatic or aromatic polyol, in particular an aliphatic or cycloaliphatic polyol. Component B1 may in particular comprise a saturated polyol. Preferably, component B1 comprises a saturated aliphatic polyol.

[0115] According to one embodiment, the polyol(s) contained in component B1 have a molar mass of less than 400 g / mol, less than 350 g / mol, less than 300 g / mol, less than 250 g / mol, less than 200 g / mol or less than 150 g / mol. Examples of suitable polyols are ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,10-decanediol, 1,12-dodecanediol, diethylene glycol, triethylene glycol, dipropylene glycol, tripropylene glycol, polyalkylene glycols such as polyethylene glycol or polypropylene glycol (preferably with a number average molecular weight Mn, calculated from the OH number, ranging from 250 to 3000 g / mol), 1,4-cyclohexanedimethanol, 1,6-cyclohexanedimethanol, 1,4-cyclohexanediol, bisphenol A, hydrogenated bisphenol A, glycerol, diglycerol, triglycerol, tetraglycerol, pentaglycerol, a polyglycerol (iea mixture of glycerol oligomers such as Polyglycerol-3 which is a mixture of glycerol oligomers containing a majority proportion of triglycerol), tricyclodecane dimethanol, trimethylolpropane, di(trimethylolpropane), trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, erythritol, pentaerythritol, di(pentaerythritol), neopentyl glycol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,3-propanediol, 2-methyl-1,2-propanediol, sorbitol, mannitol, xylitol, isosorbide, isoidide, isomannide, methyl glucoside, polyester polyols (in particular polycaprolactone polyol), polycarbonate polyols, polyorganosiloxane polyols (in particular polydimethylsiloxane polyol), a hydroxy-terminated polybutadiene, a diol derived from a dimer or trimer of hydrogenated or non-hydrogenated fatty acid, alkoxylated derivatives (in particular ethoxylated and / or propoxylated) of the polyols mentioned above, and mixtures thereof.

[0116] According to a particular embodiment, component B1 comprises a saturated aliphatic polyol chosen from trimethylolethane, trimethylolpropane, glycerol, diglycerol, triglycerol, tetraglycerol, pentaglycerol, a polyglycerol, di(trimethylolpropane), pentaerythritol, dipentaerythritol, sorbitol, a diol derived from a dimer or trimer of hydrogenated or non-hydrogenated fatty acid, alkoxylated derivatives (in particular ethoxylated and / or propoxylated) of the polyols mentioned above, and mixtures thereof.

[0117] Component B1 represents from 0 to 50%, in particular from 10 to 40%, more particularly from 20 to 30% of the total weight of components A and B. In other words, the alkyd resin comprises from 0 to 50%, in particular from 10 to 40%, more particularly from 20 to 30%, by weight of units derived from a polyol relative to the total weight of the alkyd resin.

[0118] The alcohol component B may comprise a monoalcohol component B2. The component B2 comprises at least one monoalcohol. The component B2 may comprise a mixture of monoalcohols. In particular, the component B2 consists of all the monoalcohols used to prepare the alkyd resin.

[0119] The monoalcohol may in particular be an aliphatic, cycloaliphatic or aromatic monoalcohol, in particular aliphatic or cycloaliphatic. The monoalcohol may in particular be a saturated monoalcohol. Preferably, the monoalcohol is a saturated aliphatic monoalcohol.

[0120] The monoalcohol may in particular be a C6-C60 monoalcohol, in particular C8-C55, more particularly C10-C50.

[0121] Examples of suitable monoalcohols are octan-1-ol, octan-2-ol, 2-ethyl-1-hexanol, nonan-1-ol, decan-1-ol, undecan-1-ol, lauryl alcohol, myristyl alcohol, cetyl alcohol, stearyl alcohol, docosanol, alkoxylated (especially ethoxylated and / or propoxylated) derivatives of the above-mentioned monoalcohols, and mixtures thereof.

[0122] Component B2 represents from 0 to 20%, in particular from 0 to 10%, more particularly from 0 to 5% of the total weight of components A and B. In other words, the alkyd resin comprises from 0 to 20%, in particular from 0 to 10%, more particularly from 0 to 5%, by weight of units derived from a monoalcohol relative to the total weight of the alkyd resin.

[0123] The alkyd resin may in particular have a number-average molecular weight Mn ranging from 2500 to 9000 g / mol, in particular from 3500 to 6000 g / mol. The number-average molecular weight can in particular be measured by GPC in THF in polystyrene equivalents.

[0124] The acid number of the alkyd resin may in particular be less than 25 mg KOH / g, preferably 5 to 20 mg KOH / g, more preferably 6 to 13 mg KOH / g.

[0125] The hydroxyl number of the alkyd resin may in particular be 20 to 150 mg KOH / g, preferably 30 to 100 mg KOH / g.

[0126] The alkyd resin can in particular have an average functionality f ranging from 1.8 to 2.1. This average functionality is defined according to the following relationship: f = 2 Zj nifj / Zi ni with ni and f being respectively the number of moles and functionality of the acid or alcohol component i (average over all the reactive acid and alcohol components).

[0127] The alkyd resin may in particular have a cone-plate viscosity at 125°C according to the ISO 2884-1:1999 method ranging from 1,500 to 4,000 mPa.s, preferably from 2,000 to 3,000 mPa.s.

[0128] The weight ratio of the alkyd resin relative to the weight of the alkyd emulsion may range from 35 to 65%, in particular from 40 to 60%, more particularly from 45 to 55%.

[0129] Surfactant

[0130] The alkyd emulsion according to the invention may comprise a surfactant component, also called a T-component. The T-component comprises a surfactant. The T-component may comprise a mixture of surfactants.

[0131] For the purposes of the present invention, a surfactant is an amphiphilic compound (i.e. having both a hydrophilic part and a hydrophobic part). The surfactant must in particular be capable of stabilizing the alkyd resin in the form of droplets dispersed in water. In particular, a surfactant suitable for forming an oil-in-water emulsion may have a hydrophilic-lipophilic balance (HLB) value greater than 8, in particular greater than 10, more particularly greater than 12.

[0132] Component T may comprise a surfactant selected from an anionic surfactant, a cationic surfactant and mixtures thereof. Preferably, component T comprises a mixture of an anionic surfactant and a non-ionic surfactant. For example, the weight ratio of anionic surfactant to non-ionic surfactant may be 1 to 4, preferably 1 to 3, more preferably 1.5 to 2.5.

[0133] Component T may in particular comprise an anionic surfactant selected from an alkyl sulfate, an alkyl ether sulfate, an alkylsulfonate, an alkylbenzenesulfonate, an optionally substituted diphenyl oxide disulfonate, an optionally alkoxylated sulfosuccinate mono- or diester, a phosphonate mono- or diester, a phosphate mono- or diester, a polymerizable anionic surfactant and mixtures thereof. A list of suitable surfactants is available in the book "Surfactants and Polymers in Aqueous Solutions" (Holmberg et al., 2002, John Wiley & Sons).

[0134] Examples of suitable alkyl sulfates and alkyl ether sulfates are optionally ethoxylated C6-C22 fatty alcohol sulfates, such as decyl sulfate, lauryl sulfate (such as Disponil® SLS), stearyl sulfate, C12-C14 fatty alcohol ether sulfate with 2 to 50 EO units (such as Disponil® FES 77, Disponil® FES 27, Disponil® FES 993, Disponil® FES 32, Rhodapex LA 120s).

[0135] Examples of suitable alkylsulfonates are C6-C22 fatty alcohol sulfonates such as decyl sulfonate, lauryl sulfonate and stearyl sulfonate.

[0136] Examples of suitable alkylbenzenesulfonates are benzenesulfonates substituted with a linear or branched C6-C22 alkyl group, such as sodium dodecylbenzenesulfonate (such as POLYSTEP® A-16-22, Rhodacal® DS-4).

[0137] An example of a suitable diphenyl ether disulfonate is sodium dodecyl diphenyl ether disulfonate (such as Dowfax® 2A1, Calfax® DB45). Examples of suitable sulfosuccinate mono- or diesters are optionally alkoxylated C6-C22 alkyl monoesters or diesters of sulfosuccinic acid (such as Aerosol® A-102, Aerosol® MA-80, Aerosol® GPG).

[0138] Examples of suitable phosphate mono- or diesters are compounds of formula (I) or (II) (such as Rhodafac® Rs 410, Rhodafac® Rs 610, Rhodafac® Rs 710, Rhodafac® Rs 960, Rhodafac® Re 610, Hostaphat® 1306): monoester RO(R'O) n - P(=O) [-O' M + ]2 (I) diester [RO(R'O) n ]2- P(=O)-O' M + (II) wherein each R is independently C6 to C50, preferably C8 to C30, more preferably C1 to C20 alkyl; each R' is independently ethylene or propylene; n ranges from 2 to 50, preferably from 4 to 40, more preferably from 8 to 30;

[0139] M is selected from hydrogen, a metal cation (particularly sodium or potassium) or an ammonium.

[0140] Phosphate mono- and diesters may in particular be in the form of a mixture, the weight ratio of phosphate monoester to phosphate diester being able to be from 0.8 to 1.2.

[0141] The anionic surfactant may be a polymerizable anionic surfactant (i.e. an ethylenically unsaturated surfactant), in particular a polymerizable surfactant based on phosphate, phosphonate, sulfate, sulfonate, sulfosuccinate or carboxylate, more particularly a polymerizable surfactant based on sulfate.

[0142] The polymerizable anionic surfactant may comprise an aromatic ring. In particular, the polymerizable anionic surfactant may comprise a carbon-carbon double bond in the alpha or beta position of the aromatic ring, more particularly in the alpha position of the aromatic ring.

[0143] The polymerizable anionic surfactant may in particular correspond to the following formula (Ia): [Chem 2] in which

[0144] Z is an ethylenically unsaturated group, preferably a group of formula -CH=CH2, -CH=CHCH3OR -CH2-CH=CH2each R 1is independently selected from H, alkyl, alkenyl, alkoxy, aryl and alkylaryl;

[0145] L is a bond, alkylene, oxyalkylene or polyoxyalkylene;

[0146] X comprises a hydrophilic group, preferably chosen from -SO3M, -CO2M, -P(Y)O2M, -C(=O)-CH(SO3M)-CH2-C(=O)-Y OR -C(=O)-CH2-CH(SO3M)-C(=O)-Y, more preferably -SO3M;

[0147] M is H, a metal cation (especially sodium or potassium) or ammonium;

[0148] Y is OM or a residue of the following formula (Ib):

[0149] [Chem 3]

[0150] The polymerizable anionic surfactant may in particular correspond to the following formula (the):

[0151] [Chem 4] in which R 1 and M are as defined above; each A is independently C2-C4 alkylene, preferably ethylene or propylene; n is 1 to 100, 2 to 60, 3 to 50, 4 to 40 or 5 to 30.

[0152] The polymerizable anionic surfactant may in particular correspond to the following formula (Id): [Chem 5] in which A, M and n are as defined above; m is 1 or 2.

[0153] Examples of suitable polymerizable anionic surfactants are available under the references Hitenol® BC-3025, Hitenol® AR-1025, Hitenol® AR-10, Hitenol® KH-1025, Hitenol® KH-10, Hitenol® KH-05, Hitenol® BC-20, Hitenol® BC-1025, Hitenol® BC-20 from Dai-lchi Kogyo Seiyaku.

[0154] According to a particular embodiment, the component ? comprises an anionic surfactant selected from a phosphate monoester, a phosphate diester and mixtures thereof.

[0155] Component T may in particular comprise a non-ionic surfactant selected from an optionally alkoxylated fatty alcohol, an optionally alkoxylated fatty acid, an optionally alkoxylated sorbitol ester, an optionally alkoxylated fatty ester, an ethoxy-propoxy block copolymer (EO-PO copolymer), a polymerizable non-ionic surfactant and mixtures thereof. A list of suitable surfactants is available in the book "Surfactants and Polymers in Aqueous Solutions" (Holmberg et al., 2002, John Wiley & Sons).

[0156] Examples of suitable fatty alcohols are C6-C22 alkoxylated fatty alcohols with 2-50 alkoxy units, such as C12-C14 alcohol ethoxylates (such as Tergitol® 15-S-20), C13 alcohol ethoxylates (such as Emulan® TO 4070, Emulan® TO 2080), C16-C18 alcohol ethoxylates (such as Empilan® KM80), propoxylated / ethoxylated C4-C8 alcohols with a propoxy / ethoxy weight ratio of the order of 1, ethoxylated iso C10 fatty alcohol (2-40 EO), ethoxylated C10-C18 monobranched fatty alcohols (2-40 EO).

[0157] Examples of suitable sorbitol esters are C18 sorbitol esters and ethoxylated sorbitol esters (5-20 EO units).

[0158] Examples of suitable fatty acids are ethoxylated C12-C18 fatty acids (7-100 EO), ethoxylated castor oil (30-40 EO), ethoxylated hydrogenated castor oil (7-60 EO). Examples of suitable fatty esters are glycerol palmitate, glycerol stearate, ethylene glycol stearate, diethylene glycol stearate, propylene glycol stearate, polyethylene glycol 200 stearate (PEG of Mn = 200) or ethoxylated fatty esters (2-15 EO) in Cis.

[0159] Examples of ethoxy-propoxy block copolymers are Butoxy EO-PO copolymers (such as Maxemul® 7101).

[0160] The non-ionic surfactant may be a polymerizable non-ionic surfactant (i.e. an ethylenically unsaturated surfactant), in particular a polymerizable surfactant based on a polyether.

[0161] The polymerizable nonionic surfactant may comprise an aromatic ring. In particular, the polymerizable nonionic surfactant may comprise a carbon-carbon double bond in the alpha or beta position of the aromatic ring, more particularly in the alpha position of the aromatic ring.

[0162] The polymerizable non-ionic surfactant may in particular correspond to the following formula (Ha): in which

[0163] Z' is an ethylenically unsaturated group, preferably a group of formula -CH=CH2, -CH=CHCH3OR -CH2-CH=CH2each R 3 is independently selected from H, alkyl, alkenyl, alkoxy, aryl and alkylaryl; each A is independently C2-C4 alkylene, preferably ethylene or propylene; n is 1 to 100, 2 to 60, 3 to 50, 4 to 40 or 5 to 30.

[0164] The polymerizable non-ionic surfactant may in particular correspond to the following formula (llb): [Chem 7] in which R3 , A and n are as defined above.

[0165] The polymerizable non-ionic surfactant may in particular correspond to the following formula (Ile):

[0166] [Chem 8]

[0167] Alk in which A and n are as defined above;

[0168] Alk is alkyl, preferably C6-C30.

[0169] The polymerizable nonionic surfactant may be an aliphatic surfactant.

[0170] The polymerizable non-ionic surfactant may in particular correspond to the following formula (Ilia):

[0171] [Chem 9] in which

[0172] L is a C6-C30 alkylene, preferably branched;

[0173] Z” is an ethylenically unsaturated group, preferably a group of formula

[0174] R 4 and R 5are independently selected from H and methyl; each A is independently C2-C4 alkylene, preferably ethylene or propylene; n is from 1 to 100, from 2 to 60, from 3 to 50, from 4 to 40 or from 5 to 30.

[0175] Examples of suitable polymerizable non-ionic surfactants are available under the references Noigen® RN-10, Noigen® RN-20, Noigen® RN-30, Noigen® RN-40, Noigen® RN-5065, Noigen® KN-10, Noigen® AN 5065, Noigen® AN-30, Noigen® AN-20, Noigen® AN-10 from the company Dai-lchi Kogyo Seiyaku. According to a particular embodiment, the component T comprises a non-ionic surfactant selected from an ethoxy-propoxy block copolymer.

[0176] The weight ratio of component T relative to the weight of the alkyd emulsion varies from 1 to 15%, preferably from 2 to 12% and more preferably from 3 to 10%.

[0177] The alkyd emulsion according to the invention can in particular be prepared according to the process described below.

[0178] Process for the preparation of an alkyd emulsion

[0179] The invention also relates to a process for preparing an alkyd emulsion, the process comprising the following steps: i) preparing a molten alkyd resin, the alkyd resin being based on an acid component A and an alcohol component B; ii) adding a surfactant component T and water; iii) partially neutralizing the acidity of the reaction mixture by adding lithium hydroxide; iv) neutralizing at least part of the residual acidity of the reaction mixture by adding sodium hydroxide; v) emulsification by phase inversion; vi) optionally adjusting the dry extract of the alkyd emulsion.

[0180] The alkyd resin of step i) may in particular be prepared by polycondensation of an acid component A and an alcohol component B. Components A and B may in particular be as described above. Components A and B may be heated to a temperature ranging from 80 to 250°C. The water formed during the polycondensation may be gradually removed by distillation. The progress of the polycondensation may be controlled by the acid number of the reaction mixture. Once the desired acid number is reached, the alkyd resin may be cooled to room temperature (20-30°C) to be stored for subsequent emulsification.

[0181] Alternatively, the alkyd resin may be directly introduced in the molten state (for example at a temperature of 80 to 110°C) into step ii) of the process according to the invention.

[0182] Step ii) may be carried out by adding component T and water to the reaction medium. Component T may in particular be as described above. Step ii) may be carried out at a temperature ranging from 80 to 100°C.

[0183] Step iii) may in particular be carried out by adding lithium hydroxide, in particular by adding an aqueous solution of lithium hydroxide. Step iii) may be carried out at a temperature ranging from 60 to 85°C. The quantity of lithium hydroxide introduced into the reaction medium is adjusted so that the neutralization is partial, i.e. the alkyd resin has carboxylic acid groups in free form (-COOH) at the end of step iii). This advantageously makes it possible to consume all of the lithium hydroxide introduced into the reaction medium.

[0184] Step iv) may in particular be carried out by adding sodium hydroxide, in particular by adding an aqueous sodium hydroxide solution. Step iv) may be carried out at a temperature ranging from 60 to 85°C. The neutralization carried out in step iv) is not necessarily total, i.e. the alkyd resin may have carboxylic acid groups in free form (-COOH) at the end of step iv).

[0185] The molar ratio between the lithium hydroxide introduced in step iii) and the sodium hydroxide introduced in step iv) may in particular range from 1 to 50, preferably from 5 to 30, more preferably from 10 to 20. Alternatively, the molar ratio between the lithium hydroxide introduced in step iii) and the sodium hydroxide introduced in step iv) may range from 1 to 20, preferably from 2 to 15, more preferably from 3 to 10.

[0186] Step v) can in particular be carried out by gradually adding water to the reaction mixture with stirring. The temperature of the reaction mixture can be maintained at a temperature ranging from 60 to 85°C. Once emulsification is complete, the temperature of the reaction medium can be allowed to return to room temperature (20 to 25°C).

[0187] Optional step vi) may be carried out by adding water to obtain the desired dry extract. In particular, the dry extract may be adjusted to reach 35 to 65%, preferably 40 to 60%, more preferably 45 to 55%.

[0188] Composition, coating and use

[0189] Another subject, according to the invention, relates to a coating composition comprising an alkyd emulsion as defined above.

[0190] The composition may include a drying agent. The drying agent increases the polymerization rate of the alkyd resin. Drying agents are typically metal salts, including salts of cadmium, tin, cobalt, manganese, zirconium, lead, iron, or calcium; or organic compounds such as fatty acids.

[0191] According to another embodiment, the composition does not comprise a drying agent and dries simply with the oxygen in the air. It is then sufficient for the aqueous phase to be eliminated naturally by drying. The composition according to the invention can be applied to a wide variety of substrates, including wood, metal, stone, plaster, concrete, glass, fabric, leather, paper, plastic, composite. The application can be carried out in a conventional manner, in particular with a brush or roller, by spraying, immersion or covering.

[0192] After applying the composition, the water can be removed naturally by air drying, particularly at room temperature or by heating.

[0193] The composition may in particular be a coating, sealant or adhesive composition.

[0194] In particular, the composition may be a coating composition, more particularly a decorative coating composition, in particular a film, paint, varnish, lacquer, stain, adhesion primer or ink composition.

[0195] According to a particular embodiment, the composition is a paint, varnish or stain composition, in particular a finishing paint, varnish or stain composition. Such a composition can in particular be applied indoors or outdoors, for example on wood, metal, a wall or plastic.

[0196] The composition can in particular be used to obtain a coating (in particular a film, a paint, a varnish, a lacquer, a stain, an adhesion primer or an ink), an adhesive or a mastic.

[0197] Another subject of the invention relates to the use of the alkyd emulsion according to the invention, as a binder for obtaining a coating (in particular a film, a paint, a varnish, a lacquer, a stain, an adhesion primer or an ink), an adhesive or a mastic.

[0198] The invention also relates to a coating (in particular a film, a paint, a varnish, a lacquer, a stain, an adhesion primer or an ink), an adhesive or a mastic obtained by applying and drying the composition according to the invention.

[0199] The following examples illustrate the invention and its performance and in no way limit its scope. EXPERIMENTAL SECTION

[0200] Raw materials

[0201] The raw materials used in the examples are described in Table 1 below. [Table 1]

[0202] Tests and measurement methods

[0203] These tests and methods are generally valid for the characteristics cited in the description and in particular in the examples presented. Dry extract

[0204] Evaluation according to ISO 3251:2008 according to the conditions: 1 g of dispersion for

[0205] 1 hour at 125°C and the result is expressed as a %.

[0206] Cone-plate viscosity

[0207] The cone-plate viscosity of alkyd resin is measured at 125°C according to ISO 2884-1:1999 and expressed in mPa.s.

[0208] Brookfield Viscosity

[0209] The Brookfield viscosity of the alkyd emulsion is measured at 23°C, with a Brookfield DVII apparatus (S34 spindle) according to ISO 3219:1993.

[0210] Particle size

[0211] The particle size of the alkyd emulsion is measured using a Zetasizer-Malvern Instruments Ltd. apparatus. The dispersion sample is diluted in a transparent tank using filtered deionized water. The volume average particle size (Dv50) is measured by 90° laser scattering.

[0212] Acid Number and Hydroxyl Number

[0213] The acid value of alkyd resin is evaluated according to ISO 3682:1996. The hydroxyl value of alkyd resin is evaluated according to ISO 4326:2019.

[0214] Storage stability

[0215] Storage stability is the variation in the dry extract of the alkyd emulsion at 50°C for 1 month. Storage stability consists of measuring the dry extract on the surface of the sample and comparing it with the dry extract measured at the bottom of the sample. If after one month of storage at 50°C, the difference in the measured dry extract is not greater than 2%, the stability is considered good.

[0216] Water resistance

[0217] The water resistance of a coating is measured on films with a thickness of 150 μm obtained by applying a formulation using a Leneta P121-10N card filmograph and drying for 24 hours at 23°C (+ / -2°C) with a humidity level of 50%. After drying, water drops are placed on the surface of the paint film. As many water drops as the chosen contact time (for example: 5 min, 15 min, 30 min, 1 h, 2 h, 4 h, 8 h, 16 h or even 24 h) can be covered (with a watch glass, a bottle cap, etc.) and / or placed on a small piece of filter paper to slow down evaporation (recommended for long contact times). After the chosen contact time has elapsed, gently remove the drop with absorbent paper and assess the condition of the test surface. A rating will be made immediately after removing the water drop.A second rating will be carried out after reconditioning the test specimen for 24 hours in an air-conditioned room at 23°C and 50% RH, in order to assess the coating's ability to regain its initial appearance. Water resistance is assessed qualitatively according to the following scale:

[0218] 4: No visible change

[0219] 3: Slight change in gloss visible when the light source is reflected on the test surface / Coating swelling / Color variation (whitening) / Coating softening

[0220] 2: Appearance of a change in the structure of the coating (light blistering, wrinkling) 1: Significant change in the structure of the coating (intense blistering)

[0221] Hardness

[0222] The coating hardness is measured on films with a thickness of 100 μm obtained according to the method described in the measurement of water resistance. The pendulum is cleaned with acetone. The film is placed under the pendulum. The pendulum is gently brought onto the surface of the film. The pendulum is deflected, without moving the pivot laterally, to the appropriate angle (i.e. 12° for the Persoz pendulum) and temporarily blocked with a rod. The counter is reset to zero and the pendulum is released. The measurement is finished when the pendulum is stopped and the counter no longer increments. The value is recorded. Three measurements are made on each film and the average of the three values ​​is taken.

[0223] Shine

[0224] The measurements are carried out using a BYK Gardner GmbH “micro-TRI-gloss” gloss meter with a geometry of 207 60°, and 85° after 24 hours of drying in an air-conditioned room (at 23°C ± 1°C and at 50% ± 5% RH) of wet films of 200 pm deposited on glass plates and according to the ISO 2813 (2014) standard.

[0225] Bio-based renewable carbon (BRC) content

[0226] The BRC is calculated by determining the percentage of carbon atoms from a raw material of biological origin compared to the total number of carbon atoms in the formulation.

[0227] The formulations to be evaluated were applied to two Leneta 2A cards at a thickness of 150 μm, using a filmograph. These paints were stored in a climate-controlled room (at 23°C ± 1°C and 50% ± 5% RH or at 50°C ± 1°C and 50% ± 5% RH) for a specified time. The yellowing index Yi (= “Yellowing Index”) was determined on a “Dr Lange” Micro Color LMC spectrocolorimeter according to ASTM 313-96 on dry films at different drying times.

[0228] The 150 pm wet film thickness is applied to Leneta cards using a Bird filmograph.

[0229] 1.1) Synthesis of alkyd resin

[0230] In a 2-liter reactor comprising:

[0231] - a diving rod for introducing nitrogen,

[0232] - a temperature probe,

[0233] - a refrigerant supplied with water at 12°C, and

[0234] - a tank to recover the water from polycondensation, the following raw materials were used:

[0235] - 793 g of FOR 85

[0236] - 239 g of Sylfat® 2

[0237] - 331 g of Polyglycerol-3,

[0238] - 42 g of sebacic acid and

[0239] - 125 g of succinic acid.

[0240] Under nitrogen bubbling, FOR 85, Sylfat® 2 and sebacic acid were introduced. The mixture was heated to 250°C using an electric heating mantle and the water formed was distilled as it formed until an acid number of 7 mg KOH / g was obtained. The reaction mixture was cooled to 200°C and succinic acid was introduced. The mixture was heated to 250°C until an acid number of 7.5 mg KOH / g was obtained. At the end of the synthesis, a viscous alkyd resin with the following characteristics was obtained:

[0241] - Acid number: 7.6 mg KOH / g

[0242] - Dry extract: 100%

[0243] - Cone-plate viscosity: 2,800 mPa.s 1.2) Emulsification of the alkyd resin to obtain an alkyd emulsion

[0244] In a 1 liter reactor, 391 g of alkyd resin obtained according to the operating conditions of 1.1) described above, previously melted at 80-100°C, were introduced. When the reactor temperature was stabilized at 95°C, 15.6 g of Hostaphat® 1306 and 7.8 g of Maxemul® 7101 were introduced. The mixture was left stirring for 30 minutes. 117.5 g of water were then introduced. When the temperature reached 65°C, 35.52 g of LiOH monohydrate (10% by weight aqueous solution) were introduced to partially neutralize the reaction mixture. The mixture was left stirring at 65°C for 30 minutes. 8.9 g of NaOH (10% by weight aqueous solution) were then introduced to finalize the neutralization of the reaction mixture. The mixture was left stirring at 65°C for 30 minutes. Finally, 262 g of water were added over a period of 2 hours, while maintaining the temperature at 65°C.The reactor was then cooled to room temperature and the dry extract adjusted to 50%. The final product was an alkyd emulsion with the following characteristics:

[0245] Dry extract: 50.5% pH: 9.3

[0246] Brookfield viscosity at 23°C: 197 mPa.s

[0247] Particle size: 173 nm Storage stability: good Free lithium hydroxide content: < 10 ppm

[0248] Example 2 (comparative)

[0249] Example 1 was reproduced by performing a single neutralization step with 44.89 g of LiOH monohydrate (10% by weight aqueous solution).

[0250] In the end, an alkyd emulsion was obtained which has the following characteristics: Dry extract: 50.5% pH: 8.9

[0251] Brookfield viscosity at 23°C: 133 mPa.s

[0252] Particle size: 153 nm Storage stability: good Free lithium hydroxide content: 800 ppm

[0253] Example 3 (comparative)

[0254] Example 1 was reproduced by performing a single neutralization step with 42.73 g of NaOH (10% by weight aqueous solution).

[0255] With a comparable dry extract, an alkyd emulsion of similar quality (particle size, pH, viscosity, storage stability) was obtained to that obtained in Example 1. Formulation

[0256] The alkyd emulsions were formulated into a gloss paint with a pigment volume concentration (PVC) of 45% and a TiCh content of 22% with an iron-based drying agent. The raw materials used for the formulation are detailed in Table 3.

[0257] [Table 3]

[0258] The properties of the paints obtained are detailed in Table 4.

[0259] [Table 4]

[0260] The coating based on an alkyd neutralized with lithium and sodium salts has properties equivalent to those of a coating based on an alkyd neutralized with lithium salts only, but it does not contain free lithium hydroxide. On the other hand, neutralizing the alkyd with sodium salts only degrades the properties of the resulting coating, particularly in terms of yellowing and hardness development.

Claims

CLAIMS

1. An alkyd emulsion, characterized in that it comprises an alkyd resin, the alkyd resin being based on an acid component A and an alcohol component B, the alkyd resin comprising lithium carboxylate groups and sodium carboxylate groups.

2. Alkyd emulsion according to claim 1, characterized in that the ratio between the number of lithium carboxylate groups and the number of sodium carboxylate groups ranges from 1 to 50, preferably from 5 to 30, more preferably from 10 to 20.

3. Alkyd emulsion according to claim 1 or 2, characterized in that the alkyd resin has an oil length of 10 to 60%, in particular 20 to 50%, more particularly 20 to 40%.

4. An alkyd emulsion according to any one of claims 1 to 3, characterized in that component A comprises a rosin component A1, preferably component A1 comprises a resin acid or a resin acid derivative.

5. Alkyd emulsion according to any one of claims 1 to 4, characterized in that component A comprises a conjugated fatty acid component A2, preferably component A2 comprises at least one conjugated fatty acid derived from a modified vegetable oil, more preferably at least one conjugated fatty acid derived from dehydrated castor oil, isomerized sunflower oil, isomerized linseed oil, isomerized soybean oil, more preferably still a conjugated fatty acid derived from dehydrated castor oil.

6. An alkyd emulsion according to any one of claims 1 to 5, characterized in that the acid component A comprises a polyacid component A3, in particular the component A3 comprises at least one saturated aliphatic polyacid, more particularly sebacic acid, succinic acid or a mixture thereof.

7. Alkyd emulsion according to one of claims 1 to 6, characterized in that the alcohol component B comprises a polyol component B1, in particular a polyol component B1 having a functionality ranging from 2 to 6, in particular from 2.5 to 5.5, more particularly from 3 to 5.

8. Alkyd emulsion according to claim 7, characterized in that component B1 comprises at least one saturated aliphatic polyol chosen from trimethylolethane, trimethylolpropane, glycerol, diglycerol, triglycerol, tetraglycerol, pentaglycerol, a polyglycerol, di(trimethylolpropane), pentaerythritol, dipentaerythritol, sorbitol, a diol derived from a dimer or trimer of hydrogenated or non-hydrogenated fatty acid, alkoxylated derivatives of the polyols mentioned above, and mixtures thereof.

9. Alkyd emulsion according to one of claims 1 to 8, characterized in that the weight ratio of the alkyd resin relative to the weight of the alkyd emulsion varies from 35 to 65%, preferably from 40 to 60%, more preferably from 45 to 55%.

10. Alkyd emulsion according to one of claims 1 to 9, characterized in that the acid number of the alkyd resin is less than 25 mg KOH / g, preferably 5 to 20 mg KOH / g, more preferably 6 to 13 mg KOH / g.

11. Alkyd emulsion according to any one of claims 1 to 10, characterized in that the emulsion comprises a surfactant component T, in particular a component ? comprising a surfactant selected from an anionic surfactant, a non-ionic surfactant and mixtures thereof.

12. Alkyd emulsion according to claim 11, characterized in that the weight content of component T relative to the weight of the alkyd emulsion varies from 1 to 15%, preferably from 2 to 12% and more preferably from 3 to 10%.

13. A process for preparing an alkyd emulsion as defined in one of claims 1 to 12, characterized in that the process comprises the following steps: i) preparation of an alkyd resin in the molten state, the alkyd resin being based on an acid component A and an alcohol component B; ii) addition of a surfactant component T and water; iii) partial neutralization of the acidity of the reaction mixture by adding lithium hydroxide; iv) neutralization of at least part of the residual acidity of the reaction mixture by adding sodium hydroxide; v) emulsification by phase inversion vi) optionally adjustment of the dry extract of the alkyd emulsion.

14. Process according to claim 13, characterized in that the molar ratio between the lithium hydroxide introduced in step iii) and the sodium hydroxide introduced in step iv) ranges from 1 to 50, preferably from 5 to 30, more preferably from 10 to 20.

15. Composition characterized in that it comprises an alkyd emulsion as defined according to one of claims 1 to 12 or obtained by the process as defined according to claim 13 or 14.

16. Composition according to claim 15, characterized in that it is a coating, sealant or adhesive composition, in particular a coating composition, more particularly a film, paint, varnish, lacquer, stain, adhesion primer or ink composition.

17. Use of the alkyd emulsion as defined according to one of claims 1 to 12 or obtained by the process as defined according to claim 13 or 14, as a binder for obtaining a coating, an adhesive or a sealant, in particular for obtaining a coating, more particularly for obtaining a film, a paint, a varnish, a lacquer, a stain, an adhesion primer or an ink.

18. A coating, adhesive or sealant obtained by applying and drying the composition according to claim 15 or 16.

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