Two-component system for polyurethane adhesives

Abstract

The invention relates to a two-component system for polyurethane adhesives comprising a polyisocyanate mixture, to the use of the two-component systems according to the invention for polyurethane adhesives, to a method for bonding at least one substrate, and to the bonded substrate.

Description

[0001] 2025PF30046-Abroad

[0002] - 1 -

[0003] Two-component system for polyurethane adhesives

[0004] The invention relates to a two-component system for polyurethane adhesives comprising a polyisocyanate mixture, the use of the two-component systems for polyurethane adhesives according to the invention, a method for bonding at least one substrate and the bonded substrate.

[0005] Two-component adhesive systems are adhesives in which the components (a) adhesive component and (b) crosslinker component are typically stored in separate containers due to their reactivity. Polyisocyanates are frequently used as the crosslinker component.

[0006] Pentamethylene diisocyanate (PDI), derived from bio-based raw materials, is a potential monomeric diisocyanate for the production of sustainable polyisocyanates. WO2024 / 115350 A1 describes a low-viscosity PDI allophane polyisocyanate.

[0007] Particularly for applications in the adhesive sector, for example for the production of multilayer composite films, there was a need for polyisocyanate mixtures that have sufficiently low viscosities and at the same time exhibit high bond strength after sterilization.

[0008] The object of the present invention was therefore to provide sustainable two-component systems for polyurethane adhesives that overcome at least some of the disadvantages of the prior art and can be used to produce composite materials with improved sterilization resistance (bond strength after sterilization).

[0009] Within the scope of this invention, sterilization resistance is understood to mean the strength of a multilayer film composite consisting of polyester film type Hostaphan RNK 2-CSR, 23 µm / adhesive according to the invention and a pre-laminate of aluminum foil / sterilization-resistant adhesive / cast polypropylene film Actebond ASB-203 + HAT-038-S-LV (12 µm aluminum / 50 µm cast polypropylene film “Innofol”), measured after 60 minutes of sterilization and 24 hours of subsequent storage under standard climate conditions, with regard to the strength of the bond between the polyester film and the pre-laminate. To meet this requirement, an object of the present invention is a two-component system for polyurethane adhesives comprising a component A), comprising at least one polyol, and a component B), comprising a polyisocyanate mixture, comprising at least one polyisocyanate M) of the general formula (I)2025PF30046-Ausland

[0010] - 2 -

[0011]

[0012] in which

[0013] R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (6 to 22) - p carbon atoms, each of which may optionally be substituted, R' and R“ independently represent hydrogen or an aliphatic residue with 1 to 10

[0014] carbon atoms, where at least one of the R' and R" substituents represents hydrogen,

[0015] n for an integer from 1 to 12,

[0016] m for an integer from 1 to 10 and

[0017] p stands for 0 or 1

[0018] and at least one polyisocyanate N) other than polyisocyanate M) with uretdione, isocyanurate, iminooxadiazindione, urethane, allophane, biuret and / or oxadiazintrione structure bearing aliphatic, cycloaliphatic, araliphatic and / or aromatically bonded isocyanate groups,

[0019] wherein components A) and B) are present in a weight ratio of 70 : 30 to 99.9 : 0.1, preferably of 80 : 20 to 99 : 1 and particularly preferably of 90 : 10 to 97 : 3.

[0020] According to the invention, the terms "comprising" and "containing" preferably mean "essentially consisting of" and particularly preferably "consisting of". The further embodiments mentioned in the claims and in the description can be combined as desired, unless the context clearly indicates otherwise. "At least one", as used herein, refers to one or more, for example, two, three, four, five, six, seven, eight, nine, or more. In connection with constituents of the compounds described herein, this term does not refer to the absolute quantity of molecules, but to the type of constituent. "At least one polyol" therefore means, for example, that only one type of polyol or several different types of polyols may be present, without specifying the quantity of each individual compound.

[0021] Numerical values ​​given herein without decimal places refer to the full value given with one decimal place. For example, "99%" means "99.0%". 2025PF30046-Abroad

[0022] - 3 - Numeric ranges specified in the format "in / from x to y" include the values ​​mentioned. If multiple preferred numeric ranges are specified in this format, it is understood that all ranges resulting from the combination of the different endpoints are also included.

[0023] In this context, the term "aliphatic" is defined as non-aromatic hydrocarbon groups that are saturated or unsaturated.

[0024] For the purposes of this document, the term "aliphatic" is defined as aliphatic hydrocarbon residues, whether saturated or unsaturated, that contain at least one aromatic substituent. For the purposes of this document, the term "alicyclic" or "cycloaliphatic" is defined as optionally substituted, carbocyclic or heterocyclic compounds or units that are not aromatic (such as cycloalkanes, cycloalkenes, or oxa-, thia-, aza-, or thiazacycloalkanes). Specific examples include cyclohexyl groups, cyclopentyl groups, and their N- or O-heterocyclic derivatives, such as pyrimidine, pyrazine, tetrahydropyran, or tetrahydrofuran.

[0025] In the event that the groups or compounds are disclosed as "optionally substituted" or "substituted", suitable substituents are -F, -CI, -Br, -I, -OH, -OCH3, OCH2CH3, -O-isopropyl or -one-propyl, -OCF3, -CF3, -S-Ci-6-alkyl and / or (optionally via an attached heteroatom) a linear or branched, aliphatic and / or alicyclic structural unit with 1 to 12 carbon atoms, each acting as a replacement for a carbon-bound hydrogen atom of the molecule in question. Preferred substituents are halogen (in particular -F, -CI), Ci-6-alkoxy (in particular methoxy and ethoxy), hydroxy, trifluoromethyl and trifluoromethoxy, each acting as a replacement for a carbon-bound hydrogen atom of the molecule in question.

[0026] The two-component polyurethane adhesive systems according to the invention contain a component A), comprising at least one polyol (hereinafter also referred to as polyhydroxyl compound A) or polyol component A).

[0027] Component A)

[0028] Suitable polyols as component A) for the two-component systems according to the invention are, for example, polyester polyols, polyether polyols, polycarbonate polyols, polyester carbonate polyols, polyurethane polyols, polyacrylate polyols, or any mixtures of such polyhydroxyl compounds. Suitable polyol components generally have an average OH functionality of 1.5 to 6, preferably 1.8 to 4, and particularly preferably 1.9 to 3.

[0029] Polyester polyols suitable as polyhydroxyl compounds A) can be prepared in a manner known per se by reacting polyhydric alcohols with insufficient amounts 2025PF30046-Abroad

[0030] - 4 -obtained from polyhydric carboxylic acids, corresponding carboxylic anhydrides, corresponding polycarboxylic esters of lower alcohols or lactones.

[0031] Suitable polyhydric alcohols for the production of polyester polyols are, in particular, those with a molecular weight in the range of 62 to 400 g / mol, such as... Examples include 1,2-ethanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2- and 1,3-propanediol, 1,12-dodecanediol, 1,2- and 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 4,4'-(1-methylethylidene)-biscyclohexanol, tricyclodecanedimethanol, 1,2,3-propanetriol, 1,1,1-trimethylolethane, 1,2,6-hexanetriol, 1,1,1-trimethylolpropane, 2,2-bis(hydroxymethyl)-1,3-propanediol, 1,3,5-tris(2-hydroxyethyl)-isocyanurate, xylitol, dipentaerythritol, or sorbitol, but also polyethylene glycols with molecular weights ranging from 100 to 4000. g / mol.

[0032] In subordinate quantities, monoalcohols such as 2-ethylhexanol, n-octanol, n-nonanol, n-decanol, n-tetradecanol, n-hexadecanol and isostearyl alcohol can also be used.

[0033] The acids or acid derivatives used to produce the polyester polyols A) can be aliphatic, cycloaliphatic, aromatic, and / or heteroaromatic in nature and may be substituted and / or unsaturated, for example, by halogen atoms. Examples of suitable acids include polyhydric carboxylic acids with molecular weights in the range of 118 to 300 or their derivatives, such as malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, 1,4-cyclohexanedicarboxylic acid, hexahydrophthalic acid, tetrahydrophthalic acid, phthalic acid, isophthalic acid, phthalic anhydride, trimellitic acid, pyromellitic acid, dimeric and trimeric fatty acids, dimethyl terephthalate, and bisglycol terephthalate.

[0034] In subordinate quantities, monocarboxylic acids such as caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, arachidic acid, behenic acid, dehydrated castor oil fatty acid, sunflower fatty acid, linolenic acid and / or linolenic acid, tall oil fatty acid, benzoic acid and cinnamic acid may also be used.

[0035] Hydroxycarboxylic acids, such as glycolic acid, lactic acid, mandelic acid, pivalic acid, hydroxystearic acid, ricinoleic acid, hydroxybenzoic acid, ferulic acid, dimethylolpropionic acid, tartaric acid, citric acid are also suitable starting compounds for the production of suitable polyester polyols A).

[0036] Any mixtures of these exemplary alcoholic and / or acidic starting compounds can also be used to produce polyester polyols A). 2025PF30046-Abroad

[0037] - 5 - Preferably, the polyester polyols A) are based on a combination of at least one aromatic and at least one aliphatic carboxylic acid, wherein the molar ratio of aromatic and aliphatic carboxylic acids is preferably 95:5 to 5:95, particularly preferably 80:20 and 20:80, and most preferably 70:30 and 30:70. The polyester polyols can be prepared from the aforementioned starting materials in a manner known per se by polycondensation in one or more reaction steps, optionally in the presence of solvents, preferably at temperatures in the range of 160 to 260 °C. Catalysts such as dibutyltin oxide, butylchlorotin dihydroxide, butylstananoic acid, or tetrabutoxytitanate, and / or antioxidants can optionally be used.

[0038] In addition to the aforementioned alcoholic and / or acidic starting materials for the production of polyester polyols A), lactones represent another class of suitable starting materials. They can be reacted with simple polyhydric alcohols, such as those mentioned above as examples, as starter molecules, via ring opening to give polyester polyols A), in a manner known per se. Suitable lactones include, for example, β-propiolactone, γ-butyrolactone, γ- and β-valerolactone, β-caprolactone, 3,5,5- and 3,3,5-trimethylcaprolactone, or any mixtures of such lactones. The reaction of the lactones generally takes place in the presence of catalysts such as Lewis or Brønsted acids, organotin or titanium compounds at temperatures of 20 to 200 °C, preferably 50 to 160 °C.

[0039] Preferred polyester polyols A) for the two-component systems according to the invention are those with a number-average molecular weight (determined by gel chromatography according to DIN EN ISO 13885-1) of 1,000 to 200,000 g / mol, preferably 2,000 to 100,000 g / mol, and particularly preferably 6,000 to 80,000 g / mol. Alternatively, or preferably, the polyester polyols A) have hydroxyl values ​​in the range of 0 to 120 mg KOH / g, particularly preferably 0.1 to 60 mg KOH / g, and most preferably 1 to 30 mg KOH / g.

[0040] Particularly preferred polyester polyols A) have an average weight molecular weight Mw (determined according to DIN EN ISO 13885-1) in the range of 5000 to 100,000 g / mol, particularly preferably from 6,000 to 800,000 g / mol and most preferably from 8000 to 70,000 g / mol.

[0041] The acid number of the polyester polyols A) is preferably from 0 to 10 mg KOH / g, particularly preferably 0 to 5 mg KOH / g and particularly preferably 0 to 4 mg KOH / g.

[0042] Suitable polyether polyols A) are, for example, those with a medium molecular weight of 1,000 to 30,000, preferably 2,000 to 22,000, calculable from functionality and hydroxyl number, with a hydroxyl group content of 0.1 to 3 wt.%, preferably 0.22025PF30046-Ausland

[0043] - 6 -

[0044] up to 1.7 wt%, as are accessible in suitable starter molecules known per se by alkoxylation. Any polyhydric alcohols, for example those with a molecular weight in the range of 62 to 400, as described above in the preparation of polyester polyols, can be used as starter molecules for the synthesis of these polyether polyols.

[0045] Suitable alkylene oxides for the alkoxylation reaction are in particular ethylene oxide and propylene oxide, which can be used in any order or in a mixture in the alkoxylation reaction.

[0046] The polyether polyols preferably used as polyhydroxyl compounds for the compositions according to the invention are those whose alkylene oxide units consist of at least 80 mol%, but preferably exclusively of propylene oxide units.

[0047] Suitable polyhydroxyl compounds A) of the polycarbonate type are in particular the polycarbonate compounds known per se, such as those that can be produced, for example, by reacting dihydric alcohols, such as those mentioned above in the list of polyhydric alcohols of the molecular weight range 62 to 400, with diaryl carbonates, such as diphenyl carbonate or phosgene.

[0048] Suitable polyhydroxyl compounds A) of the polyester carbonate type are in particular the diols having known ester groups and carbonate groups, such as those that can be obtained, for example, according to the teaching of DE-AS 1 770245 by reacting dihydric alcohols with lactones of the type mentioned above as an example, in particular s-caprolactone and subsequently reacting the polyester diols formed therein with diphenyl carbonate.

[0049] Particularly preferred polyols for component A) of the two-component polyurethane adhesive systems according to the invention are polyester polyols of the type mentioned. Component A) can optionally be diluted with suitable solvents, for example, the solvents inert to isocyanate groups described below in connection with the preparation of the polyisocyanate component B). If used at all, these solvents are added in an amount of up to 40 wt.%, preferably 30 wt.%, and particularly preferably 20 wt.%, based on component A).

[0050] Component B)

[0051] The two-component polyurethane adhesive systems according to the invention comprise a component B), comprising a polyisocyanate mixture, containing at least one polyisocyanate M) and at least one polyisocyanate N) different from M), preferably 2025PF30046-Abroad

[0052] - 7 - in a weight ratio to each other of 20 : 80 to 90 : 10, preferably of 25 : 75 to 85 : 15 and particularly preferably of 30 : 70 to 80 : 20.

[0053] The polyisocyanate mixture represents a physical blend and therefore differs from a purely chemically produced polyisocyanate by direct means, for example with regard to the oligomer distribution that can be determined by gel permeation chromatography according to DIN EN ISO 13885-1:2021-11.

[0054] The polyisocyanate mixture has, in each case based on the solvent-free solid resin, a color number of less than 100 APHA, preferably less than 80 APHA, particularly preferably less than 60 APHA, and / or an NCO content of 6.0 to 24.4 wt.%, preferably 6.8 to 23.2 wt.%, particularly preferably 7.0 to 22.2 wt.%, and / or a residual monomer content of less than 0.14 wt.%, preferably less than 0.12 wt.% and particularly preferably less than 0.10 wt.%, as measured by gas chromatography with an internal standard according to DIN EN ISO 10283:2007-11.

[0055] Preferably, the viscosity at 23°C of the polyisocyanate mixture, measured according to DIN EN ISO 3219:1994-10 at a shear rate of 250 s', is 1 , of less than 5000 mPas, preferably less than 4000 mPas, particularly preferably less than 3000 mPas and most particularly preferably less than 2000 mPas.

[0056] The at least one polyisocyanate M) is mixed with the at least one polyisocyanate N) such that the polyisocyanate mixture B) is obtained and the polyisocyanates M) and N) are present in the weight ratio mentioned above. By appropriately selecting the mixing ratios within the specified limits, properties such as viscosity, NCO content, and functionality of the polyisocyanate mixtures can be specifically adjusted. The mixing is carried out using any method and in any sequence, at a temperature of 0 to 60°C, preferably 10 to 50°C, particularly preferably 20 to 40°C, optionally under an inert gas atmosphere, preferably excluding moisture. The mixing is preferably carried out without solvents. However, suitable solvents inert to the reactive groups of the polyisocyanates M) and N) can optionally be used.Suitable solvents for this purpose include those produced using fossil raw materials or renewable raw materials, in particular the commonly known solvents such as ethyl acetate, butyl acetate, ethylene glycol monomethyl or ethyl ether acetate, 1-methoxypropyl-2-acetate, 3-methoxy-n-butyl acetate, ethyl (-)-L-lactate, acetone, 2-butanone, 4-methyl-2-pentanone, cyclohexanone, dihydrolevoglucosenone, toluene, xylene, chlorobenzene, white spirit, and highly substituted aromatics, such as those sold under the names solvent naphtha, Solvesso®, Isopar®, Nappar®, Varsol® (ExxonMobil Chemical Central Europe, Cologne, Germany) and Shellsol® (Shell Deutschland Oil GmbH, Hamburg, 2025PF30046-Abroad).

[0057] - 8 - DE) are commercially available, but also solvents such as dimethylfuran, 2-methyltetrahydrofuran, dimethyl isosorbide (DMI), y-valerolactone, propylene glycol diacetate, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, diethylene glycol ethyl and butyl ether acetate, N-methylpyrrolidone and N-methylcaprolactam, or any mixtures of such solvents.

[0058] To produce the polyisocyanate component B), 20 to 90 parts by weight, particularly preferably 25 to 85 parts by weight, and most preferably 30 to 80 parts by weight of polyisocyanate M), are mixed with 10 to 80 parts by weight, preferably 15 to 75 parts by weight, and most preferably 20 to 70 parts by weight of polyisocyanate N). If one or more solvents are used, these can be contained either in the at least one polyisocyanate M) and / or in the at least one polyisocyanate N), preferably in the at least one polyisocyanate N), before the mixing begins. However, in the process according to the invention, they can optionally also be added after completion or at any time during the actual mixing process.

[0059] If solvents are used at all in the production of the polyisocyanate component B), in an amount of up to 40 wt.%, preferably 30 wt.%, particularly preferably 20 wt.%, based on the sum of polyisocyanate M), polyisocyanate N) and solvent.

[0060] In the following, the polyisocyanates M) and N) are described in more detail and preferred embodiments are mentioned.

[0061] Polyisocyanate M)

[0062] The polyisocyanate M) is a special PDI allophanate polyisocyanate and is described by the general formula (I). Preferably, a general formula (I) of the at least one polyisocyanate M) is used.

[0063]

[0064] in which

[0065] R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (8 to 20) - p, particularly preferably with (10 to 18) - p and most preferably with (12 to 14) - p carbon atoms, which may optionally be substituted, 2025PF30046-Abroad

[0066] - 9 - R' and R“ independently represent hydrogen or an aliphatic residue with 1 to 10 carbon atoms, where at least one of the residues R' and R“ represents hydrogen,

[0067] n for an integer from 1 to 12,

[0068] m represents an integer from 1 to 7, particularly preferably an integer from 2 to 5 and most preferably an integer from 2 to 4, and p represents 0 or 1.

[0069] The 1,5-diisocyanatopentane (also referred to here as pentamethylene diisocyanate or PDI) used to produce the polyisocyanate M) can be produced in various ways, for example by phosgenation in the liquid or gas phase or by a phosgene-free method, such as thermal urethane cleavage, starting from 1,5-diaminopentane obtained preferably biotechnologically by decarboxylation of the naturally occurring amino acid lysine.

[0070] Preferably the polyisocyanate M) is prepared by reacting 1,5-diisocyanatopentane with at least one alcohol X) of the general formula (II)

[0071]

[0072] R" O (II), in which

[0073] R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (6 to 22) - p carbon atoms, each of which may optionally be substituted, R' and R“ independently represent hydrogen or an aliphatic residue with 1 to 10 carbon atoms, with at least one of the residues R' and R“ representing hydrogen,

[0074] m for an integer from 1 to 10 and

[0075] p represents 0 or 1.

[0076] Preferably, 1,5-Diisocyanatopentane is reacted with at least one alcohol X) of the general formula (II),

[0077]

[0078] R" O (II), in which

[0079] R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (6 to 22) - p carbon atoms, each of which may optionally be substituted, 2025PF30046-Abroad

[0080] - 10 - R' and R“ independently represent hydrogen or an aliphatic residue with 1 to 10 carbon atoms, where at least one of the residues R' and R“ represents hydrogen,

[0081] m for an integer from 1 to 10 and

[0082] p represents 0 or 1.

[0083] In the production of the polyisocyanate M), at least one alcohol of the general formula (II) is used as the alcoholic component X).

[0084]

[0085] R" O (II), for use in which

[0086] R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (6 to 22) - p, preferably with (8 to 20) - p, particularly preferably with (10 to 18) - p and most preferably with (12 to 14) - p carbon atoms, each of which may optionally be substituted,

[0087] R' and R" independently represent hydrogen or an aliphatic residue with 1 to 10 carbon atoms, where at least one of the residues R' and R" represents hydrogen, and

[0088] m for an integer from 1 to 10, preferably for an integer from 1 to 7, particularly preferably for an integer from 2 to 5 and most particularly preferably for an integer from 2 to 4, and

[0089] p represents 0 or 1.

[0090] These alcohols include, for example, the alkoxylation products of fatty alcohols of general formula (III), which are known per se.

[0091] R 1 -OH (Hi),

[0092] in which

[0093] R 1 for a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with 6 to 22, preferably 8 to 20, particularly preferably 10 to 18, most particularly preferably 12 to 14 carbon atoms, each of which may optionally be substituted,

[0094] and / or fatty acids of general formula (IV)

[0095] R 2 -COOH (IV),2025PF30046-Abroad

[0096] - 11 -in which

[0097] R 2for a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with 5 to 21, preferably 7 to 19, particularly preferably 9 to 17, most preferably 11 to 13 carbon atoms, each of which may optionally be substituted.

[0098] In the aforementioned fatty alcohols of general formula (III), p represents 0 and R in general formula (I) and general formula (II). 1 for R, including the aforementioned preferences for R 1 . Likewise, R are also present as residues. 1 and also R, which are exemplarily suitable, preferred and particularly preferred, are the residues derived from the fatty alcohols named below as exemplarily suitable, preferred and particularly preferred.

[0099] In the aforementioned fatty acids of general formula (IV), p represents 1 and R in general formula (I) and general formula (II). 2for R, including the aforementioned preferences for R 2 . Likewise, R are also present as residues. 2 and also R, which are exemplarily suitable, preferred and particularly preferred, are the residues derived from the fatty acids named below as exemplarily suitable, preferred and particularly preferred.

[0100] Fatty alcohols suitable for alkoxylation are, for example, 1-hexanol (caproic alcohol), 1-heptanol (enanth alcohol), 1-octanol (caprylic alcohol), 1-nonyl alcohol (pelargon alcohol), 1-decanol (capric alcohol), 1-dodecanol (lauryl alcohol), 1-tetradecanol (myristyl alcohol), 1-hexadecanol (cetyl alcohol), 1-heptadecanol (margaryl alcohol), 1-octadecanol (stearyl alcohol), 1-eicosanol (arachidyl alcohol), 1-docosanol (behenyl alcohol), 1-tetracosanol (lignoceryl alcohol), 1-hexacosanol (ceryl alcohol), 1-octacosanol (montanyl alcohol), 1-triacontanol (melissyl alcohol), c / s-9-Hexadecen-1-ol (palmitoleyl alcohol), c / s-9-Octadecen-1-ol (oleyl alcohol), trans-9-Octadecen-1-ol (elaidyl alcohol), c / s-11-Octadecen-1-ol, c / s,c / s-9,12-Octadecadien-1-ol (linoleyl alcohol) and 6,9,12-Octadecatrien-1-ol (g-linolenyl alcohol); suitable fatty acids include, for example, hexanoic acid (caproic acid), heptanoic acid (enanthic acid), octanoic acid (caprylic acid), nonanoic acid (pelargonic acid), and decanoic acid (capric acid).Undecanoic acid, dodecanoic acid (lauric acid), tridecanoic acid, tetradecanoic acid (myristic acid), pentadecanoic acid, hexadecanoic acid (palmitic acid), heptadecanoic acid (margaric acid), octadecanoic acid (stearic acid), nonadecanoic acid, eicosanoic / icosanoic acid (arachidic acid), heneicosanoic acid and docosanoic acid (behenic acid), c / s-9-octadecenoic acid (oleic acid) and c / s-13-docosenoic acid (erucic acid).

[0101] Preference is given to fatty alcohols and fatty acids produced using vegetable and animal oils and fats. 2025PF30046-Abroad

[0102] - 12 - Particularly preferred fatty alcohols for the preparation of the alcoholic component X) are 1-decanol, 1-dodecanol, 1-tetradecanol, and 1-octadecanol; 1-dodecanol and 1-tetradecanol are particularly preferred. Particularly preferred fatty acids are decanoic acid, dodecanoic acid, tetradecanoic acid, and hexadecanoic acid; dodecanoic acid and tetradecanoic acid are particularly preferred. For the preparation of the alcoholic component X) by alkoxylation of the aforementioned fatty alcohols and / or fatty acids, any alkylene oxides with 2 to 12 carbon atoms, such as ethylene oxide, propylene oxide, 1,2-epoxybutane, 1,2-epoxyhexane, 1,2-epoxyoctane, or 1,2-epoxydodecane, are suitable, which can be used in any order or in a mixture in the alkoxylation reaction. Preferred alkylene oxides are those with 2 to 4 carbon atoms. Particularly preferred alkylene oxides for the preparation of the alcoholic component X) are ethylene oxide and propylene oxide.

[0103] The number of carbon atoms of the residues R' or R" in general formula (I) can be determined from the alkylene oxides mentioned above as examples and preferably. Thus, R' and R" in general formula (I) and / or formula (II) independently represent hydrogen or an aliphatic residue with preferably 1 to 2 carbon atoms, wherein at least one of the residues R' and R" represents hydrogen.

[0104] Suitable alcoholic components X) for the production of the polyisocyanates M) are, in particular, alkoxylation products of the aforementioned fatty acids and / or fatty alcohols, which on average have 1 to 10, preferably 1 to 7, particularly preferably 2 to 5, and most preferably 2 to 4 alkylene oxide units. The numbers and ranges of numbers mentioned above as statistical means constitute the inventive and preferred integers m in general formula (I) and general formula (II). In a further preferred embodiment, alkoxylation products are used as the alcoholic component X) which on average have 1 to 10, preferably 1 to 7, particularly preferably 2 to 5, and most preferably 2 to 4 alkylene oxide units, wherein the alkylene oxide units preferably comprise or consist of ethylene oxide and / or propylene oxide units.The numbers and number ranges mentioned above as statistical means yield the integers m according to the invention and preferred in general formula (I) and general formula (II).

[0105] The alcoholic components X) preferably have a pH value, measured at a 1% solution of the respective alcoholic component X) in water, of 4.0 to 8.0, preferably of 4.5 to 7.5, particularly preferably of 5.0 to 7.0, and / or total alkali cation contents of a maximum of 100 ppm, preferably of 1 to 70 ppm, particularly preferably of 2 to 50 ppm. 2025PF30046-Abroad

[0106] - 13 - If necessary, component X) may contain other alcoholic compounds in subordinate amounts in addition to the aforementioned alkoxylation products of fatty alcohols and / or fatty acids.

[0107] These include, for example, monoalcohols such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol, sec-butanol, the isomeric pentanoyl, hexanol, octanol and nonanol, n-decanol, n-dodecanol, n-tetradecanol, n-hexadecanol, n-octadecanol, cyclohexanol, the isomeric methylcyclohexanols, hydroxymethylcyclohexane, 3-methyl-3-hydroxymethyloxetane, benzyl alcohol, phenol, the isomeric cresols, octylphenols, nonylphenols and naphthols, furfuryl alcohol and tetrahydrofurfuryl alcohol, unbranched aliphatic diols, such as... B. 1,2-Ethanediol, 1,3-Propanediol, 1,4-Butanediol, 1,5-Pentanediol, 1,6-Hexanediol, 1,7-Heptanediol and 1,8-Octanediol, cycloaliphatic diols, such as 1,2- and 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 4,4'-(1-Methylethylidene)-biscyclohexanol, triols such as 1,2,3-propanetriol, 1,1,1-trimethylolethane, 1,2,6-Hexanetriol, 1,1,1-Trimethylolpropane, and 1,3,5-Tris(2-hydroxyethyl)isocyanurate, tetrafunctional alcohols, such as2,2-Bis(hydroxymethyl)-1,3-propanediol or any mixtures of such alcohols.

[0108] If any, these further alcoholic compounds are used for the production of the polyisocyanate M) in amounts of a maximum of 25 wt.%, preferably a maximum of 20 wt.%, particularly preferably a maximum of 15 wt.%, based on the amount of alkoxylation products of fatty alcohols and / or fatty acids used.

[0109] To produce the polyisocyanate M), 1,5-diisocyanatopentane is reacted with at least one alcoholic component X), preferably at temperatures of 40 to 200 °C, particularly preferably of 60 to 180 °C, and / or while maintaining an equivalent ratio of isocyanate groups to isocyanate-reactive groups of preferably 4:1 to 50:1, particularly preferably of 5:1 to 30:1, most preferably of 10:1 to 25:1, to form allophanate polyisocyanates.

[0110] The process for the preparation of polyisocyanate M) can be carried out uncatalyzed as a thermally induced allophanatization. However, suitable catalysts are preferably used to accelerate the allophanatization reaction. These are the usual known allophanatization catalysts, for example, metal carboxylates, metal chelates, or tertiary amines of the type described in GB-A-0994890 (page 2, lines 73 to 87), alkylating agents of the type described in US-A-3,769,318 (column 6, lines 5 to 49), or strong acids as exemplified in EP-A-0000194 (page 13, line 27 to page 14, lines 1 to 18).

[0111] Suitable allophantation catalysts are in particular zinc compounds, such as zinc(II) stearate, zinc(II) n-octanoate, zinc(II) 2-ethyl-1-hexanoate, zinc(II) naphthenate or zinc(II) acetylacetonate, tin compounds, such as tin(II) n-octanoate, tin(II) 2-ethyl-1 -2025PF30046-Abroad

[0112] - 14-hexanoate, tin(II) laurate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin dilaurate, dibutyltin dimaleate or dioctyltin diacetate, zirconium compounds such as zirconium(IV)-2-ethyl-1-hexanoate, zirconium(IV) neodecanoate, zirconium(IV) naphthenate or zirconium(IV) acetylacetonate, aluminum tri(ethylacetoacetate), iron(III) chloride, potassium octoate, manganese, cobalt or nickel compounds, and strong acids such as trifluoroacetic acid, sulfuric acid, hydrogen chloride, hydrogen bromide, phosphoric acid or perchloric acid, or any mixtures of these catalysts.

[0113] Suitable, though less preferred, catalysts for the production of polyisocyanate M) are also those compounds which, in addition to the allophanatization reaction, also catalyze the trimerization of isocyanate groups to form isocyanurate structures. Such catalysts are described, for example, in EP-A-0 649866, page 4, line 7 to page 5, line 15.

[0114] Preferred catalysts for the production of the polyisocyanate M) are zinc and / or zirconium compounds of the type mentioned above. The use of at least zinc(II) n-octanoate, zinc(II) 2-ethyl-1-hexanoate and / or zinc(II) stearate, zirconium(IV) n-octanoate, zirconium(IV) 2-ethyl-1-hexanoate and / or zirconium(IV) neodecanoate is particularly preferred.

[0115] These catalysts are used in the production of the polyisocyanate M), if at all, preferably in an amount of 0.001 to 5 wt.%, particularly preferably 0.005 to 1 wt.%, based on the total weight of the reactants PDI and X), and can be added both before the start of the reaction and at any time during the reaction.

[0116] Preferably, lead octoate is not used as a catalyst in the production of the polyisocyanates M), and thus a polyisocyanate mixture according to the invention is preferred which is free of catalytic amounts, and particularly preferably free of detectable amounts of lead octoate.

[0117] The polyisocyanate M) is preferably produced solvent-free. However, suitable solvents inert to the reactive groups of the starting components can also be used if necessary. Suitable solvents include, for example, the solvents described above as suitable for the process according to the invention or any mixtures of such solvents.

[0118] In one possible embodiment, during the production of the polyisocyanate M), the PDI is placed at a temperature between 20 and 100°C, optionally under an inert gas, such as nitrogen, and optionally in the presence of a suitable solvent of the type mentioned. Subsequently, the alcoholic component X) is added in the 2025PF30046-Abroad

[0119] - 15 -The quantity specified above is added, and the reaction temperature for the urethanization is adjusted, if necessary by a suitable measure (heating or cooling), to a temperature of 30 to 120°C, preferably 50 to 100°C. Following the urethanization reaction, i.e., when the NCO content theoretically corresponding to a complete conversion of isocyanate and hydroxyl groups has been reached, the allophanatization can be started, for example, without the addition of a catalyst, by heating the reaction mixture to a temperature of 140 to 200°C. Preferably, however, suitable catalysts of the type mentioned above are used to accelerate the allophanatization reaction, whereby, depending on the type and quantity of the catalyst used, temperatures in the range of 60 to 140°C, preferably 80 to 120°C, are generally sufficient.

[0120] In another possible embodiment of the process for producing the polyisocyanate M), the catalyst to be used is added to the PDI and / or the alcoholic component X) before the actual reaction begins. In this case, the urethane groups formed as intermediates react spontaneously to form the desired allophane structure. In this type of single-stage reaction, the PDI, optionally containing the catalyst, is typically heated—optionally under an inert gas, such as nitrogen, and optionally in the presence of a suitable solvent of the type mentioned—at temperatures optimal for allophanetization in the range of 60 to 140°C, preferably 80 to 120°C, and reacted with the alcoholic component X), optionally containing the catalyst.

[0121] However, it is also possible to add the catalyst to the reaction mixture at any point during the urethanization reaction. In this embodiment of the process, the temperature for the pure urethanization reaction, which takes place before the catalyst is added, is generally set in the range of 30 to 120°C, preferably 50 to 100°C. After the addition of a suitable catalyst, the allophanatization reaction is finally carried out at temperatures of generally 60 to 140°C, preferably 80 to 120°C.

[0122] The reaction progress in the process for the production of polyisocyanate M) can be monitored, for example, by titrimetric determination of the NCO content according to DIN EN ISO 11909:2007-05. After reaching the desired NCO content, preferably when the degree of allophanatization (i.e., the percentage of urethane groups that are intermediately formed from the hydroxyl groups of component X and converted to allophanate groups, which can be calculated from the NCO content) of the reaction mixture is at least 80%, particularly preferably at least 90%, and most preferably when the NCO content corresponding to complete allophanatization is reached or falls below the threshold, 2025PF30046-Ausland

[0123] - 16 - the reaction is terminated. In purely thermal reactions, this can be achieved, for example, by cooling the reaction mixture to room temperature. However, when preferably using an allophantation catalyst of the type mentioned, the reaction is generally stopped by adding suitable catalyst poisons, for example, acids such as phosphoric acid, or acid chlorides such as benzoyl chloride or isophthaloyl dichloride.

[0124] Preferably, the reaction mixture is subsequently freed from volatile components (excess PDI, any solvents used and, if no catalyst poison is used, any active catalyst) by thin-film distillation in high vacuum, for example at a pressure of less than 1.0 mbar, preferably less than 0.5 mbar, particularly preferably less than 0.2 mbar, under the gentlest possible conditions, for example at a temperature of 100 to 200 °C, preferably 120 to 180 °C.

[0125] The resulting distillates, which, in addition to the unreacted PDI and any solvents used, may contain an active catalyst if no catalyst poison is used, can be readily used for re-allophanatization in the process for the production of polyisocyanate M). In a further embodiment of the process for the production of polyisocyanate M), the aforementioned volatile components are separated from the oligomerization product by extraction with suitable solvents inert to isocyanate groups, for example, aliphatic or cycloaliphatic hydrocarbons such as pentane, hexane, heptane, cyclopentane, or cyclohexane.

[0126] Regardless of the specific method used to produce them, the polyisocyanates M) are clear, practically colorless polyisocyanates which, based on the solvent-free solid resin, have color numbers of less than 100 APHA, preferably less than 80 APHA, particularly preferably less than 60 APHA, and / or an NCO content of 6.0 to 18.0 wt.%, preferably 8.0 to 16.0 wt.%, particularly preferably 10.0 to 15.0 wt.%, and / or a residual monomer content of less than 0.14 wt.%, preferably less than 0.12 wt.% and particularly preferably less than 0.10 wt.%, as measured by gas chromatography with an internal standard according to DIN EN ISO 10283:2007-11. The viscosities of the polyisocyanates M) measured according to DIN EN ISO 3219:1994-10 at a shear rate of 250 s-1 at 23°C are preferably less than 500 mPas, particularly preferably less than 400 mPas, and most preferably less than 300 mPas.

[0127] Polyisocyanate N)2025PF30046-Abroad

[0128] - 17 - Polyisocyanates N) for the polyisocyanate mixture according to the invention and the process according to the invention are any polyisocyanates with uretdione, isocyanurate, allophanate, biuret, iminooxadiazindione and / or oxadiazinetrione structure produced by modifying simple aliphatic, cycloaliphatic, araliphatic and / or aromatic diisocyanates and / or triisocyanates, as described for example in J. Prakt. Chem.

[0129] 336 (1994) 185 - 200, in DE-A 1 670666, DE-A 1 954093, DE-A 2414413, DE-A 2452532, DE-A 2641 380, DE-A 3 700209, DE-A 3900053 and DE-A 3928503 or in EP-A 0336 205, EP-A 0 339 396 EP-A 0 798299, EP-A 0962454, EP-A 0 962455, EP-A 2 785 760, EP-A 2 883 895, EP-A 3 107 922, EP-A 3 107 948 and EP-A 3 337 836 are described by way of example or any mixtures of such polyisocyanates.

[0130] Suitable diisocyanates and triisocyanates for the production of polyisocyanates N) are any diisocyanates and triisocyanates accessible in various ways, for example by phosgenation of the corresponding diamines or triamines, which can be produced using fossil raw materials or renewable raw materials, optionally using mass balance, in the liquid or gas phase or by phosgene-free means, such as thermal urethane cleavage, preferably those in the molecular weight range of 140 to 400 with aliphatic, cycloaliphatic, araliphatic and / or aromatically bonded isocyanate groups, such as... B. 1,4-Diisocyanatobutane, 1,5-Diisocyanatopentane (PDI), 1,6-Diisocyanatohexane (HDI), 2-Methyl-1,5-diisocyanatopentane, 1,5-Diisocyanato-2,2-dimethylpentane, 2,2,4- or 2,4,4-Trimethyl-1,6-diisocyanatohexane, 1,8-Diisocyanatooctane, 1,9-Diisocyanatononane, 1,10-Diisocyanatodecane, 1,3- and 1,4-Diisocyanatocyclohexane, 1,3- and 1,4-bis-(isocyanatomethyl)cyclohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate, IPDI), 2,4'- and 4,4'-diisocyanatodicyclohexylmethane (H12-MDI), 4,4'-Diisocyanato-3,3'-dimethyldicyclohexylmethane, 4,4'-Diisocyanato-3,3',5,5'-tetramethyldicyclohexylmethane, 4,4'-Diisocyanato-1,1'-bi(cyclohexyl), 4,4'-Diisocyanato-3,3'-dimethyl-1,T-bi(cyclohexyl), 4,4'-Diisocyanato-2,2',5,5'-tetra-methyl-1,1'-bi(cyclohexyl), 1,8-Diisocyanato-p-menthane, 1,3-Diisocyanatoadamantane, 1,3-Dimethyl-5,7-diisocyanatoadamantane, 1-isocyanato-1-methyl-4(3)isocyanato-methylcyclohexane, Bis-(isocyanatomethyl)norbornane (NBDI), 4-isocyanatomethyl-1,8-octanediisocyanate (Triisocyanatoonane; TIN), 1,3- and 1,4-Bis(isocyanatomethyl)benzene (Xylylene diisocyanate, XDI), 1,3- and 1,4-Bis-(2-isocyanato-prop-2-yl)benzene (TMXDI), 1,3-Bis(isocyanatomethyl)-4-methylbenzene, 1,3-Bis(isocyanatomethyl)-4-ethylbenzene, 1,3-Bis(isocyanatomethyl)-5-methylbenzene, 1,3-Bis(isocyanatomethyl)-4,5-dimethylbenzene, 1,4-Bis(isocyanatomethyl)-2,5-dimethylbenzene, 1,4-Bis(isocyanatomethyl)-2,3,5,6-tetramethylbenzene, 1,3-Bis(isocyanatomethyl)-5-tert-butylbenzene, 1,3-Bis(isocyanatomethyl)-4-chlorobenzene, 1,3-Bis(isocyanatomethyl)-4,5-dichlorobenzene, 1,3-Bis(isocyanatomethyl)-2,4,5,6-tetrachlorobenzene, 1,4-Bis(isocyanatomethyl)-2,3,5,6-2025PF30046-Foreign

[0131] - 18-tetrachlorobenzene, 1,4-bis(isocyanatomethyl)-2,3,5,6-tetrabromobenzene, 1,4-bis(2-isocyanatoethyl)benzene and 1,4-bis(isocyanatomethyl)naphthalene, 1,2-, 1,3- and 1,4-diisocyanatobenzene (phenylene diisocyanate), 2,4- and 2,6-diisocyanatotoluene (TDI), 2,3,5,6-tetramethyl-1,4-diisocyanatobenzene, the isomeric diethylphenylene diisocyanates, diisopropylphenylene diisocyanates, diisododecylphenylene diisocyanates and biphenyl diisocyanates, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 2,2'-, 2,4'- and 4,4'-diisocyanatodiphenylmethane (MDI), 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, 4,4'-diisocyanatodiphenylethane, 1,5-diisocyanatonaphthalene (naphthylene diisocyanate, NDI), diphenyl ether diisocyanate, ethylene glycol diphenyl ether diisocyanate, diethylene glycol diphenyl ether diisocyanate, 1,3-Propylene glycol diphenyl ether diisocyanate, benzophenone diisocyanate, triisocyanatobenzene, 2,4,6-triisocyanatotoluene, trimethylbenzene triisocyanate, diphenylmethane-2,4,4'-triisocyanate, 3-methyldiphenylmethane-4,6,4'-triisocyanate,the isomeric naphthalene triisocyanates and methyl naphthalene diisocyanates, triphenylmethane triisocyanate, 2,4-diisocyanato-1-[(5-isocyanato-2-methylphenyl)methyl]benzene or mixtures of at least two such diisocyanates and triisocyanates.

[0132] If necessary, when modifying the aforementioned diisocyanates and / or triisocyanates to polyisocyanates (N), monoisocyanates, particularly those with a molecular weight in the range of 99 to 300, such as n-butyl isocyanate, n-amyl isocyanate, n-hexyl isocyanate, n-heptyl isocyanate, n-octyl isocyanate, undecyl isocyanate, dodecyl isocyanate, tetradecyl isocyanate, cetyl isocyanate, stearyl isocyanate, cyclopentyl isocyanate, cyclohexyl isocyanate, 3- or 4-methylcyclohexyl isocyanate, benzyl isocyanate, phenyl isocyanate, or naphtyl isocyanate, may also be used in subordinate quantities. If used at all, monoisocyanates are employed in amounts of up to 30 wt.%, preferably up to 20 wt.%, and particularly preferably up to 10 wt.%, based on the total amount of mono-, di-, and triisocyanates.

[0133] In the production of polyisocyanates (N), the actual modification reaction is generally followed by a further process step to separate the unreacted excess monomeric diisocyanates and / or triisocyanates and optionally monoisocyanates. This monomer separation is carried out according to methods known per se, preferably by thin-film distillation under vacuum or by extraction with suitable solvents inert to isocyanate groups, for example, aliphatic or cycloaliphatic hydrocarbons such as pentane, hexane, heptane, cyclopentane, or cyclohexane.

[0134] In a further preferred embodiment, the polyisocyanate N) has aliphatic, araliphatic and / or cycloaliphatic bonded isocyanate groups, preferably based on 2025PF30046-Ausland

[0135] - 19 -of 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 1,3-bis(isocyanatomethyl)benzene, bis-(isocyanatomethyl)norbornane and / or 4,4'-diisocyanatodicyclohexylmethane, and particularly preferably contains at least isocyanurate structures based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 1,3-bis(isocyanatomethyl)benzene, bis-(isocyanatomethyl)norbornane and / or 4,4'-diisocyanatodicyclohexylmethane, and most preferably contains isocyanurate structures based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane and / or Contains 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane.

[0136] In a further preferred embodiment, the polyisocyanate N) has aromatically bonded isocyanate groups, preferably from monomeric 2,4- and / or 2,6-TDI obtained by reaction with polyols and / or oligomerization, preferably trimerization, having a urethane and / or isocyanurate structure, or mixtures of at least two such polyisocyanates. The polyisocyanates can be produced by any known process, for example those described in DE-A 870400, DE-A 953012, DE-A 1 090 196, EP-A 0546399, CN 105218780, CN 103881050, CN 101717571, US 3 183 112, EP-A 0416 338, EP-A 0751 163, EP-A 1 378529, EP-A 1 378530, EP-A 2 174967, JP 63260915 or JP 56059828.

[0137] Finally, polyisocyanates N) that bear both aromatic and aliphatic isocyanate groups are also suitable, preferably mixed trimerizates or allophanates of 2,4- and / or 2,6-diisocyanatotoluene with 1,6-diisocyanatohexane. Such polyisocyanates are, for example, the mixed trimerizates or allophanates of 2,4- and / or 2,6-TDI with HDI described in DE-A 1 670667, EP-A 0078991, EP-A 0696606 and EP-A 0807623.

[0138] Preferably, the polyisocyanates used in the polyisocyanate mixture according to the invention are polyisocyanates of the type mentioned, which, based on the solvent-free form, have an isocyanate group content of 6.0 to 26.0 wt.%, preferably 8.0 to 25.0 wt.%, particularly preferably 10.0 to 24.0 wt.%, and a monomeric diisocyanate content of less than 0.14 wt.%, preferably less than 0.12 wt.%, particularly preferably less than 0.10 wt.%. In the alternative, optional case where triisocyanates and / or monoisocyanates were used to produce the polyisocyanates N), the aforementioned residual monomer contents of less than 0.14 wt.%, preferably less than 0.12 wt.%, particularly preferably less than 0.10 wt.% refer to the sum of all residual contents of all diisocyanates, triisocyanates, and monoisocyanates used. The NCO levels will be 2025PF30046-abroad

[0139] - 20 -according to DIN EN ISO 11909:2007-05, the residual monomer contents were determined by gas chromatography with internal standard according to DIN EN ISO 10283:2007-11.

[0140] Particularly preferred polyisocyanates N) are polyisocyanates containing at least isocyanurate structures based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 1,3-bis(isocyanatomethyl)benzene, bis-(isocyanatomethyl)norbornane and / or 4,4'-diisocyanatodicyclohexylmethane and most preferably polyisocyanates containing at least isocyanurate structures based on 1,5-diisocyanatopentane.

[0141] Two-component polyurethane adhesive system

[0142] The two-component polyurethane adhesive systems according to the invention contain 70 to 99.9 wt.% of component A) and 0.1 to 30 wt.% of component B). Particularly preferred two-component polyurethane adhesives contain 80 to 99 wt.% of component A) and 1 to 20 wt.% of component B). Very preferred two-component polyurethane adhesives contain 90 to 97 wt.% of component A) and 3 to 10 wt.% of component B).

[0143] Two-component polyurethane adhesive systems can be prepared by simply mixing components A) and B). Preferably, component A) or the at least one polyol is placed first, and component B) or the at least one polyisocyano mixture is added while stirring.

[0144] To facilitate the mixing of components A) and B), both the at least one polyol and the at least one polyisocyanate mixture can optionally be diluted with suitable solvents, for example the solvents inert to isocyanate groups described above in the preparation of the polyisocyanates.

[0145] The two-component polyurethane adhesive systems according to the invention can be used alone or with binders, additives, and tensile materials known in coating and adhesive technology, in particular light stabilizers such as UV absorbers and sterically hindered amines (HALS), antioxidants, fillers, and other additives, e.g., leveling agents, reactive diluents, plasticizers, catalysts, auxiliary solvents, and / or thickeners, and additives such as pigments, dyes, or matting agents. Tackifiers can also be added optionally.

[0146] These binders, additives and tensile aggregates can be added to the two-component polyurethane adhesive systems according to the invention immediately before processing. 2025PF30046-Abroad

[0147] - 21 - can be added. However, it is also possible to add at least some of these substances before or during the dispersion of the binder.

[0148] The selection and dosage of these substances, which can be added to the individual components and / or the overall mixture, are known in principle to those skilled in the art and can be tailored to the specific application without undue effort and determined through simple preliminary tests. Solvents optionally included in the two-component adhesive systems according to the invention can be present in the weight proportions already described above in component A) and / or in component B).

[0149] The addition of the aforementioned auxiliary and tensile additives to the two-component adhesive systems according to the invention, if any, is carried out in such quantities that the combined proportion of components A) and B), based on the total quantity of the two-component system, is 80.0 wt.% or more, preferably 90.0 wt.% or more, more preferably 95.0 wt.% or more, even more preferably 99.0 wt.% or more, most preferably 99.5 wt.% or more or 100.0 wt.%.

[0150] If auxiliary and drawing additives are added to the polyisocyanate mixture B) before the mixing of components A) and B), this is done, if at all, in such quantities that the combined proportion of the polyisocyanates M) and N), based on the total amount of the polyisocyanate mixture B), is 80.0 wt.% or more, preferably 90.0 wt.% or more, more preferably 95.0 wt.% or more, even more preferably 99.0 wt.% or more, most preferably 99.5 wt.% or more or 100.0 wt.%.

[0151] The two-component adhesive systems according to the invention, which consist of at least one NGO-reactive compound A), preferably a polyhydroxyl compound A), and a polyisocyana mixture B) as a crosslinking component, are ideally suited for bonding different materials, such as wood, metal, plastic, paper, textile, ceramic, glass or stone.

[0152] The two-component adhesive systems according to the invention are suitable for various joining processes, as described, for example, in Brockmann et al., Klebtechnik, Wiley CH, 2005 Weinheim, ISBN 978-3-527-31091-6, Chapter 8, and Meier-Westhues et al., Polyurethane Lacke Kleb- und Dichtstoffe, ISBN 3-86630-896-5 Hannover Vincenz 2007, in particular in Chapter 6.3.2.

[0153] The two-component adhesive systems according to the invention are particularly suitable for bonding different materials in the production of multilayer composites, especially multilayer composites with at least one metal foil, such as those used, for example, for food packaging. They lead to 2025PF30046-Ausland

[0154] - 22 -high heat resistance of the bond and high bond strengths, which are not only maintained under hot sterilization conditions but are even significantly improved. A description of this application can be found in Meier-Westhues et al., Polyurethane Coatings, Adhesives and Sealants, ISBN 3-86630-896-5, Hannover Vincenz 2007, especially in chapter 6.3.4.

[0155] A further object of the invention is an adhesive bonding process and a process for producing a multilayer composite comprising or consisting of the following steps: I) Providing at least two layers,

[0156] II) Applying the two-component polyurethane adhesive system according to the invention directly or indirectly to at least one of the two provided layers,

[0157] III) Bonding the layers and curing the two-component adhesive system while maintaining the multi-layer composite.

[0158] Another object of the invention is the use of the two-component systems according to the invention for the production of multilayer composites, in particular as a laminating adhesive or as a mounting adhesive, and especially preferably for the production of multilayer composites consisting of a synthetic substrate and a substrate with a metallic surface.

[0159] The invention also relates to a multilayer composite, obtainable or produced by the inventive method or by using the inventive two-component polyurethane adhesive systems. Preferably, the multilayer composite is a packaging material or a component in the automotive interior.

[0160] The following examples serve to illustrate the present invention, but should in no way be understood as limiting the scope of protection. 2025PF30046-Abroad

[0161] - 23 - Examples

[0162] Unless otherwise stated, all percentages refer to weight. NCO content was determined titrimetrically according to DIN EN ISO 11909:2007-05. All viscosity measurements were performed using a Physica MCR 51 rheometer from Anton Paar Germany GmbH (DE) according to DIN EN ISO 3219:1994-10 at a shear rate of 250 s'. 1 .

[0163] The residual monomer content was measured by gas chromatography with an internal standard according to DIN EN ISO 10283:2007-11.

[0164] The sodium and potassium cation concentrations were determined by inductively coupled plasma atomic emission spectrometry (ICP-OES) according to DIN EN ISO 11885:2009-09 after microwave digestion. The detection limit for this method is <1 ppm. The platinum-cobalt color number was measured spectrophotometrically according to DIN EN ISO 6271-2:2005-03 using a LICO 400 spectrophotometer from Lange, Germany.

[0165] The contents (mol-%) of the allophanate, urethane and, if applicable, isocyanurate and / or uretdione structures present in the polyisocyanates M) and N) were determined from the integrals of proton-decoupled 13¹³C NMR spectra (recorded on a Bruker DPX-400 instrument) were calculated and refer to the sum of allophanate, urethane, isocyanurate, and / or uretdione structures present. In the case of PDI and HDI polyisocyanates dissolved in CDCh, the individual structural elements exhibit the following chemical shifts (in ppm): allophanate: 155.7 and 153.8; urethane: 156.3; isocyanurate: 148.4; uretdione: 157.1.

[0166] The production of multilayer composites was carried out using a K Control Coater model 623 / 624 (K101 / K202) hand-held laminator. This involved laminating an aluminum-polypropylene pre-laminate (Actebond ASB-203 + HAT-038-S-LV (12pm aluminum / 50pm cPP “Innofol”) with a PET film (Hostaphan RNK 2-CSR, 23pm), between which the adhesive to be tested was applied. For this purpose, the aluminum pre-laminate was clamped into the hand-held laminator (aluminum side facing up). This film, as well as all subsequent films of the laminate, were DIN A4 size. The two-component adhesive was then applied in a bead to the top edge of the first clamped film (aluminum side) immediately after the production process described in the examples. The adhesive was then evenly distributed across the film using a squeegee.The two-component adhesive was heated with a Steinei HL2002LE heat gun for 10 seconds at 100°C, resulting in a surface temperature (adhesive surface) of 60°C. In the next step, an acrylate-pre-vaporized PET film (type Hostaphan2025PF30046-Ausland) was applied to the shiny aluminum surface now coated with the adhesive.

[0167] - 24 - RNK 2-CSR, 23pm) laminated. The resulting composite was then stored for 7 days under standard climate conditions (NK, 23 degrees C, 50% relative humidity).

[0168] After one week of storage at standard climate conditions, the resulting adhesive patches were sterilized in a Systec V-65 sterilizer (Systec GmbH Labortechnik, Wettenberg) using a modified program 1 (60 minutes instead of 30) at 121 °C for 60 minutes, according to the operating instructions. The total sterilization time, including heating and cooling phases, was approximately 75 minutes.

[0169] After removal from the sterilizer, the samples were superficially dried and measured immediately and after storage at standard climate for 24 hours.

[0170] To determine the peel strength of the composites (composite strength), the composite films, produced as described in the previous section, were cut into 15 mm wide strips. The strips were then peeled at 23°C in a Zwick universal peel strength testing machine (type 5kN Allround Table-top BT2-FA005TH.A50.002) at a speed of 100 mm / min and an angle of 2 x 90° (180°), and the force required was measured in Newtons.

[0171] Output connections

[0172] Polyisocyanate M)

[0173] 1234 g (8.0 mol) of PDI were placed at a temperature of 95°C under dry nitrogen with stirring and treated with 0.16 g of zinc(II)-2-ethyl-1-hexanoate as a catalyst. Over a period of approximately 45 min, 309 g (1.0 mol) of a statistically triply ethoxylated lauryl alcohol (OH number: 181.8 mg KOH / g, Na content: 28 mg / kg, K content: < 1 mg / kg) was added dropwise, during which time the temperature of the mixture rose to 100°C due to the exothermic onset of the reaction. The reaction mixture was then stirred at 100°C until the NCO content had decreased to 35.6% after approximately 1 h. The catalyst was deactivated by adding 0.16 g of orthophosphoric acid, and the unreacted monomeric PDI was separated in a thin-film evaporator at a temperature of 130°C and a pressure of 0.1 mbar. 723 g of a practically colorless, clear polyisocyanate mixture was obtained, exhibiting the following characteristics and composition:

[0174] NCO content: 14.1%

[0175] Monomeric PDI: 0.03%

[0176] Viscosity (23°C): 290 mPas

[0177] Color number (APHA): 21 Hazen

[0178] Composition: Allophanate: 70.3 mol%

[0179] Urethane: 4.2 mol%2025PF30046-Foreign

[0180] - 25 - Isocyanurate: 24.9 mol%

[0181] Uretdione: 0.6 mol-%

[0182] Polyisocyanate N)

[0183] Isocyanurate-containing PDI polyisocyanate, prepared by catalytic trimerization of PDI according to the procedure described in WO 2016 / 146579 for the polyisocyanate component A2). The reaction was deactivated at a crude NCO content of 36.7% by adding an equimolar amount of dibutyl phosphate, based on the amount of catalyst used, and stirring for 30 minutes at 80°C. Subsequently, unreacted PDI was separated by thin-film distillation at a temperature of 140°C and a pressure of 0.5 mbar.

[0184] NCO content: 21.8%

[0185] Monomeric PDI: 0.09%

[0186] Viscosity (23 °C): 9850 mPas

[0187] Color number (Hazen): 34

[0188] Polyisocyanate mixture B1)

[0189] 30 parts by weight of polyisocyanate M) were mixed homogeneously with 70 parts by weight of polyisocyanate N) by stirring at 50°C. After cooling to room temperature, a polyisocyanate mixture B1) with the following properties was obtained:

[0190] NCO content: 19.5%

[0191] Monomeric PDI: 0.04%

[0192] Viscosity (23°C): 3,000 mPas

[0193] Color number (Hazen): 25

[0194] Polyisocyanate mixture B2)

[0195] 50 parts by weight of polyisocyanate M) were mixed homogeneously with 50 parts by weight of polyisocyanate N) by stirring at 50°C. After cooling to room temperature, a polyisocyanate mixture B2) with the following properties was obtained:

[0196] NCO content: 18.0%

[0197] Monomeric PDI: 0.06%

[0198] Viscosity (23°C): 1300 mPas

[0199] Color number (Hazen): 282025PF30046-International

[0200] - 26 - Polyol component A)

[0201] A 4-liter glass reactor, equipped with a mechanical stirrer, a thermocouple, and a distillation unit with a Vigreux column, was charged with ethylenediol (100.0 g), diethylene glycol (500.0 g), 1,2-propylenediol (200.0 g), trimethylolpropane (15.0 g), isophthalic acid (580.0 g), terephthalic acid (580.0 g), and sebacic acid (310.0 g). Under a nitrogen atmosphere, the temperature was gradually increased to 250 °C, at a rate of no more than 10 °C per 10 minutes. The temperature was maintained at 250 °C until the acid number in the resin was less than 20 mg KOH / g. The Vigreux column was then removed and replaced with a standard distillation unit. A titanium isopropoxide catalyst (0.2 g) was added and a vacuum was gradually applied (< 30 mβar). The reaction progress was monitored by taking samples and measuring the acid number (AN) and the hydroxyl number (OH). The reaction was then continued until the AN was below 2 mg KOH / g.If necessary, glycol corrections were made by adding diethylene glycol and / or acid corrections by adding isophthalic acid. The polyester was cooled to 80 °C and ethyl acetate (860.0 g) was added to the resin. The final mixture had a total solids content (TSC) of 1.5 mg KOH / g, total solids content (TSC) of 18.0 mg KOH / g, total solids content (TSC) of 18.0 mg KOH / g, total mass (Mn) of 6180 g / mol, total mass (Mw) of 17564 g / mol, mean OH functionality of 2.0, and a total solids content of 70.2%.

[0202] Examples 1-4 (according to the invention and comparison)

[0203] Production of a 2-component adhesive

[0204] To produce a two-component adhesive, the polyol component A) and the respective isocyanate component were first heated at 60°C for 3 hours. Subsequently, the polyol component A) and the isocyanate component were each placed in a beaker in the quantities specified in Table 1 and, after the addition of 80 g of ethyl acetate (pa quality) to each, mixed by hand for 120 seconds using a wooden spatula, resulting in an optically homogeneous adhesive mixture.

[0205] The production of multilayer composites using the polyurethane adhesives thus obtained, sterilization of the composites, and testing for peel strength were carried out as described above. 2025PF30046-Abroad

[0206] - 27 -

[0207] Table 1

[0208] Example 1 2 3 4

[0209] (Comparison) (Comparison) (required) (required) Weighing of isocyanate component [g]

[0210] Polyisocyanate M) 7.66

[0211] Polyisocyanate N) 5.2

[0212] Polyisocyanate mixture B1) 5.66 Polyisocyanate mixture B2) 6.01 Weight of polyol component [g]

[0213] Polyol component A) 92.34 94.8 94.34 93.99 Strength after 7 d storage 4.2 FR 4.6 5.7 Strength after sterilization / immediately 2.6 1.1 3.7 3.0 Strength after sterilization / after 24 h 4.2 2.4 FR FR

[0214]

[0215] FR = Foil tear (>8 N / 15 mm), NK = 23 degrees C, 50% relative humidity

[0216] Examples 3 and 4 according to the invention, based on the polyisocyanate mixtures B1) and B2), show a high sterilization resistance (film tear after 24h, > 3 N / 15 mm after 1h), whereas comparative examples 1 and 2, based on the individual polyisocyanates M) and N), show significantly lower sterilization resistances.

Claims

2025PF30046-Abroad - 28 - Patent claims 1. Two-component system for polyurethane adhesives comprising a component A), comprising at least one polyol, and a component B), comprising a polyisocyanate mixture, comprising at least one polyisocyanate M) of general formula (I) in which R represents a linear or branched, saturated or unsaturated aliphatic and / or saturated or unsaturated cycloaliphatic residue with (6 to 22) - p carbon atoms, each of which may optionally be substituted, R' and R" independently represent hydrogen or an aliphatic residue with 1 to 10 carbon atoms, where at least one of the residues R' and R" represents hydrogen, n for an integer from 1 to 12, m for an integer from 1 to 10 and p stands for 0 or 1 and at least one polyisocyanate N) other than polyisocyanate M) with uretdione, isocyanurate, iminooxadiazindione, urethane, allophane, biuret and / or oxadiazintrione structure bearing aliphatic, cycloaliphatic, araliphatic and / or aromatically bonded isocyanate groups, wherein components A) and B) are present in a weight ratio to each other of 70 : 30 to 99.9 : 0.1, preferably of 80 : 20 to 99 : 1 and particularly preferably of 90 : 10 to 97 :

3.

2. Two-component system according to claim 1, wherein components A) and B) are present in a weight ratio to each other of 80 : 20 to 99 : 1 and particularly preferably of 90 : 10 to 97 :

3.

3. Two-component system according to claim 1 or 2, wherein the polyisocyanates M) and N) of component B) are in a weight ratio to each other of 20 : 80 to 90 : 10, 2025PF30046-Abroad - 29 - preferably from 25 : 75 to 85 : 15 and particularly preferably from 30 : 70 to 80 :

20.

4. Two-component system according to any one of claims 1 to 3, wherein the combined proportion of components A) and B), based on the total amount of the two-component system, is 80.0 wt.% or more, preferably 90.0 wt.% or more, more preferably 95.0 wt.% or more, even more preferably 99.0 wt.% or more, most preferably 99.5 wt.% or more or 100.0 wt.%.

5. Two-component system according to any one of claims 1 to 4, wherein the combined proportion of the polyisocyanates M) and N), based on the total amount of component B), is 80.0 wt.% or more, preferably 90.0 wt.% or more, more preferably 95.0 wt.% or more, even more preferably 99.0 wt.% or more, most preferably 99.5 wt.% or more or 100.0 wt.%.

6. Two-component system according to any one of claims 1 to 5, wherein the polyisocyanate N) comprises aliphatic, araliphatic and / or cycloaliphatic bonded isocyanate groups, preferably based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 1,3-bis(isocyanatomethyl)benzene, bis-(isocyanatomethyl)norbornane and / or 4,4'-diisocyanatodicyclohexylmethane, and particularly preferably at least isocyanurate structures based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane, 1,3-bis(isocyanatomethyl)benzene, bis-(isocyanatomethyl)norbornane and / or 4,4'- Diisocyanatodicyclohexylmethane contains and most preferably contains isocyanurate structures based on 1,5-diisocyanatopentane, 1,6-diisocyanatohexane and / or 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane.

7. Two-component system according to any one of claims 1 to 5, wherein the polyisocyanate N) has aromatically bonded isocyanate groups, preferably polyisocyanates obtainable from monomeric 2,4- and / or 2,6-diisocyanatotoluene by reaction with polyols and / or oligomerization, preferably trimerization, having a urethane and / or isocyanurate structure, or mixtures of at least two such polyisocyanates.

8. Two-component system according to any one of claims 1 to 5, wherein the polyisocyanate N) comprises both aromatic and aliphatic isocyanate groups, preferably mixed trimerisates or allophanates of 2,4- and / or 2,6-diisocyanatotoluene with 1,6-diisocyanatohexane. 2025PF30046-Ausland - 30 - 9. Two-component system according to one of claims 1 to 8, wherein the at least one polyol comprises polyester polyols, polyether polyols, polycarbonate polyols, polyester carbonate polyols, polyurethane polyols, polyacrylate polyols or any mixtures of such polyhydroxyl compounds.

10. Two-component system according to any one of claims 1 to 9, wherein the at least one polyol comprises polyester polyols of a number-mean molecular weight (determined by gel chromatography according to DIN EN ISO 13885-1) of 1000 to 200000 g / mol, preferably 2000 to 100000 g / mol and particularly preferably 6000 to 80000 g / mol.

11. Two-component system according to any one of claims 1 to 10, wherein the at least one polyol comprises polyester polyols with hydroxyl numbers in the range of 0 to 120 mg KOH / g, particularly preferably 0.1 to 60 mg KOH / g and most preferably 1 to 30 mg KOH / g.

12. A method for producing a multilayer composite comprising or consisting of the following steps: I) Providing at least two shifts, II) Applying the two-component polyurethane adhesive system according to any one of claims 1 to 11 directly or indirectly to at least one of the two provided layers, III) Bonding the layers and curing the two-component adhesive system while maintaining the multi-layer composite.

13. Use of the two-component systems according to any one of claims 1 to 11 for the production of multilayer composites, in particular as a laminating adhesive or as a mounting adhesive and especially preferably for the production of multilayer composites consisting of a synthetic substrate and a substrate with a metallic surface.

14. Multilayer composites obtainable or produced by a method according to claim 12 or by using the two-component polyurethane adhesive systems according to any one of claims 1 to 11.

15. Multilayer composite according to claim 14, wherein the multilayer composite is a packaging material or a part in the automotive interior.

Images