Basecoat for metal packaging

Abstract

The current invention relates to a coating composition comprising - a polyester resin, - an epoxy resin, - an isocyanate, - an acrylated polyester compound or an acrylated epoxy compound, wherein the acrylated polyester resin is different from the polyester resin or the acrylated epoxy is different from the epoxy resin, - a butylated melamine, and - optionally one or more pigment(s). This coating composition can be used as a basecoat on metal substrates that are decorated in a printing process using various types of inks.

Description

[0001] CASE: 11284PFA WO

[0002] BASECOAT FOR METAL PACKAGING

[0003] The present invention relates to a coating composition that can be used as a basecoat (white or clear) on a metal substrate. The coating composition according to the present invention is in particular suited for the application of different kind of inks (digital inks, UV inks, conventional inks). Therefore, the coating composition according to the present invention is particularly suited for use as a basecoat for metal cans, for example beverage cans.

[0004] Metal packaging is the key to many food safety concerns or to maintain the correct shelf life of chemicals or cosmetics. Such packaging is strong and seamless and provides a durable solution for storing food, blocking out contaminants or light (e.g., UV radiation). Aluminum, electrolytic tinplate or tin tree steel are most often used as the metal substrate for such packaging.

[0005] To identify the content of such packaging and also to identify the producer of such container, in most cases a decoration is applied to the outside of the packaging with such information. Often the decoration of the packaging has some attractive color or design and as such also acts as a marketing tool. Such decoration is often applied in a printing process using an ink. Since the ink normally does not adhere very well to the metal substrate, a basecoat is applied to the metal substrate to facilitate the application of the ink(s). For this, the basecoat should have a good adhesion to the metal substrate and also a good compatibility with the ink, so the ink adheres well to such basecoat.

[0006] An important parameter for the application of an ink to a metal substrate is the opacity or hiding power of the ink. The opacity or hiding powder is dimension-free value that provides a measure to the power to hide the substrate by using an ink. The higher the hiding powder, the less substrate is visible. Normally an opacity or hiding power > 1 ,6 is sufficient for a substrate printed with ink. Generally speaking, the higher the amount of ink that is used to apply to a surface, the higher the opacity or hiding power will be.

[0007] There is a need in industry to lower the amount of ink used to get a certain opacity on metal substrates, without compromising the properties of the metal substrate or the basecoat and without compromising on the type and color of the decoration that is applied to the metal substrate.CASE: 11284PFA WO

[0008] It was found that by using the coating composition of the current invention as a basecoat on metal substrates, the amount of ink that is used to obtain a certain opacity can be reduced by more than 20%, in comparison to systems that are currently available.

[0009] The coating composition according to the present invention comprises

[0010] - a polyester resin (A),

[0011] - an epoxy resin (B),

[0012] - an isocyanate (C),

[0013] - an acrylated polyester compound (D) or an acrylated epoxy compound (E), wherein the acrylated polyester resin (D) is different from the polyester resin (A) or the acrylated epoxy (E) is different from the epoxy resin (B),

[0014] - a butylated melamine (F), and

[0015] - optionally one or more pigment(s) (G).

[0016] Preferred embodiments of the coating composition according to the present invention include compositions wherein the polyester resin is a saturated polyester resin, the isocyanate is a blocked aliphatic isocyanate, and the pigment that is optionally present is a white pigment.

[0017] The polyester resin (A) that is present in the coating composition according to the present invention is in one preferred embodiment a saturated polyester resin. The polyester resin is normally solved in a suitable non-aqueous solvent, such as acetone, toluene, benzene, methyl ethyl ketone, diacetone alcohol, or solvent nafta. The polyester resin normally has a molecular weight in the range from 11.000 - 13.000 g / mol, an acid value in the range from 5 - 10 mg KOH / g, an hydroxyl value in the range from 15 - 30 mg KOH / g, a Brookfield viscosity at 25°C in the range from 8 to 17 Pa.s, and a solid content in the range from 70 - 80wt.%. Suitable commercially available polyester resins include Exter S613 (ex. Coim), Novasynt S1842-60 (ex. Novaresine), llralac SN842 S2-60 ND (ex. Covestro) and ltalester205 (ex. Galstaff).

[0018] In a pigment-free coating composition, the polyester resin is present in an amount of 55 to 62 wt.%, based upon the solid content of the coating composition.

[0019] In a pigment-containing coating composition, the polyester resin is present in an amount of 25 to 30 wt.%, based upon the solid content of the coating composition orCASE: 11284PFA WO

[0020] alternatively in an amount of 55 to 62 wt.%, based upon the solid content of the coating composition excluding any pigment(s).

[0021] The epoxy resin (B) that is present in the coating composition according to the present invention is in one preferred embodiment a bisphenol-A-based epoxy resin. The epoxy resin is normally solved in a suitable non-aqueous solvent, such as acetone, low boiling alcohols, toluene or benzene. The epoxy resin normally has an epoxy equivalent weight of 400 - 500 g / eq., a Brookfield viscosity at 25°C in the range from 7 to 12 Pa.s, and a solid content in the range from 70 to 80 wt.%. Suitable commercially available epoxy resins include Araldite GZ 7071 X75 (ex Huntsmann), DER 671 X75 (ex. Olin) and NPSN-901 X75 (ex. Midland-NanYa).

[0022] In a pigment-free coating composition, the epoxy resin is present in an amount of 5 to 7,5 wt.%, based upon the solid content of the coating composition.

[0023] In a pigment-containing coating composition, the epoxy resin is present in an amount of 2,5 to 3,5 wt.%, based upon the solid content of the coating composition or alternatively in an amount of 5 to 7,5 wt.%, based upon the solid content of the coating composition excluding any pigment(s).

[0024] The isocyanate (C) that is present in the coating composition according to the present invention is in one preferred embodiment a blocked aliphatic isocyanate, for example an alkyl-diisocyanate, like hexamethylene diisocyanate. The isocyanate is normally solved in a suitable non-aqueous solvent, such as solvent naphtha. A suitable isocyanate resin normally has a molecular weight in the range from 1000 - 3000 g / mol, an NCO-content in the range of 10,5 - 12 wt.%, a solid content in the range from 73 -77 wt.%, and a Brookfield viscosity at 25°C in the range from 2 - 4 Pa.s. Suitable commercially available isocyanates include Desmodur BL3175 SN or llradur YB147 S1 (both ex. Covestro) or llronal BN75 (ex. Galstaff).

[0025] In a pigment-free coating composition, the isocyanate is present in an amount of 8 to 11 wt.%, based upon the solid content of the coating composition.

[0026] In a pigment-containing coating composition, the isocyanate is present in an amount of 4 to 5 wt.%, based upon the solid content of the coating composition or alternatively in an amount of 8 to 11 wt.%, based upon the solid content of the coating composition excluding any pigment(s).CASE: 11284PFA WO

[0027] The acrylated polyester compound (D) that is present in the coating composition according to the present invention is different from polyester resin (A). A suitable acrylated polyester compound has a molecular weight in the range from 500 - 1500 g / mol, an acid value in the range from 0 - 25 mg KOH / m, and a Brookfield viscosity at 25°C in the range 0,4 - 0,6 Pa.s. A suitable acrylated polyester compound that can be used in the coating composition of the current invention is Ebercryl 810 (ex. Allnex). In a pigment-free coating composition, the acrylated polyester compound (D) is present in an amount of 15 to 17 wt.%, based upon the solid content of the coating composition. In a pigment-containing coating composition, the acrylated polyester compound (D) is present in an amount of 7 to 8 wt.%, based upon the solid content of the coating composition or alternatively in an amount of 15 to 17 wt.%, based upon the solid content of the coating composition excluding any pigment(s).

[0028] The acrylated epoxy compound (E) that is present in the coating composition according to the present invention is different from epoxy resin (B). The acrylated epoxy compound is normally solved in a suitable non-aqueous solvent, such as acetone, low boiling alcohols, toluene or benzene. The acrylated epoxy compound normally has a molecular weight in the range from 300 - 700 g / mol, a Brookfield viscosity at 25°C in the range from 8 to 14 Pa.s, an acid value in the range from 0 - 2 mg KOH / m, and a solid content in the range from 75 to 80 wt.%. Suitable commercially available epoxy resins include Ebercryl 605 / 20 (ex. Allnex), Etercure 621A-75 (ex. Eternal), SM61 OS-75 (ex. Jiangsu Sanmu Group), Agisyn 1010-A75 (ex. Covestro), and Qualicure GU1475A (ex. Qualipoly Chemical).

[0029] In a pigment-free coating composition, the acrylated epoxy compound (E) is present in an amount of 12,5 to 15 wt.%, based upon the solid content of the coating composition. In a pigment-containing coating composition, the acrylated epoxy compound (E) is present in an amount of 5,5 to 6,5 wt.%, based upon the solid content of the coating composition or alternatively in an amount of 12,5 to 15 wt.%, based upon the solid content of the coating composition excluding any pigment(s).

[0030] The butylated melamine (F) that is present in the coating composition according to the present invention is normally obtained by butylating the reaction product obtained by reacting melamine with formaldehyde. The butylated melamine is normally solved in aCASE: 11284PFA WO

[0031] non-aqueous solvent, such as toluene, benzene, alcohols, esters or ketones. A suitable butylated melamine compound has a molecular weight in the range from 400 - 600 g / mol, an acid value in the range from 0 - 2 mg KOH / m, a Brookfield viscosity at 25°C in the range 5 - 8 Pa.s, and a solid content in the range from 75 to 80 wt.%. Suitable commercially available butylated melamine compounds that can be used in the coating composition of the current invention include Cymel 1158 (ex Allnex) and Itamin M184 (ex. Galstaff).

[0032] In a pigment-free coating composition, the butylated melamine (F) is present in an amount of 10 to 12 wt.%, based upon the solid content of the coating composition. In a pigment-containing coating composition, the butylated melamine (F) is present in an amount of 4,5 to 5,5 wt.%, based upon the solid content of the coating composition or alternatively in an amount of 10 to 12 wt.%, based upon the solid content of the coating composition excluding any pigment(s).

[0033] The one or more pigment(s) (G), that is optionally present in the coating composition of the invention, is in one preferred embodiment a white pigment. Pigments with a different color can be used, for example if they make a better match with the colors or the inks that will be used in the further decoration of the coated substrate. An example of a pigment that can be used in the coating composition of the current invention is titanium dioxide.

[0034] To get a good covering of the substrate in combination with a good film build, the solid content of the pigment(s) in the coating composition is normally between 40 to 60 wt.%, preferable between 50 - 55 wt.%. However, the skilled person can adjust this amount, based on specific needs.

[0035] In view of the above, a typical coating composition of the present invention that is substantially free of pigment (G) and substantially free of an acrylated epoxy compound (E), has the following composition

[0036] - from 55,0 to 60,0 wt.% of a saturated polyester resin (A)

[0037] - from 5,0 to 7,0 wt.% of an epoxy resin (B)

[0038] - from 8,0 to 10,0 wt.% of a blocked aliphatic isocyanate (C)

[0039] - from 10,0 to 12,0 wt.% of butylated melamine (F), and

[0040] - from 15,0 to 17,0 wt.% of an acrylated polyester compound (D),

[0041] wherein the wt.% is calculated based upon the solid content of the coating composition.CASE: 11284PFA WO

[0042] A typical coating composition of the present invention that is substantially free of pigment (G) and substantially free of an acrylated polyester compound (D), has the following composition

[0043] - from 57,0 to 62,0 wt.% of a saturated polyester resin (A)

[0044] - from 5,5 to 7,5 wt.% of an epoxy resin (B)

[0045] - from 8,5 to 10,5 wt.% of a blocked aliphatic isocyanate (C)

[0046] - from 10,0 to 12,0 wt.% of butylated melamine (F), and

[0047] - from 12,5 to 15,0 wt.% of an acrylated epoxy compound (E),

[0048] wherein the wt.% is calculated based upon the solid content of the coating composition.

[0049] A typical pigmented coating composition of the present invention that is substantially free of an acrylated epoxy compound (E), has the following composition

[0050] - from 25,0 to 30,0 wt.% of a saturated polyester resin (A)

[0051] - from 2,5 to 3,5 wt.% of an epoxy resin (B)

[0052] - from 4,0 to 5,0 wt.% of a blocked aliphatic isocyanate (C)

[0053] - from 4,5 to 5,5 wt.% of butylated melamine (F),

[0054] - from 7,0 to 8,0 wt.% of an acrylated polyester compound (D), and

[0055] - from 40,0 to 60,0 wt.% of one or more pigment(s) (G),

[0056] wherein the wt.% is calculated based upon the solid content of the coating composition. Alternatively, a typical pigmented coating composition of the present invention that is substantially free of an acrylated epoxy compound (E), has the following composition - from 55,0 to 60,0 wt.% of a saturated polyester resin (A)

[0057] - from 5,0 to 7,0 wt.% of an epoxy resin (B)

[0058] - from 8,0 to 10,0 wt.% of a blocked aliphatic isocyanate (C)

[0059] - from 10,0 to 12,0 wt.% of butylated melamine (F),

[0060] - from 15,0 to 17,0 wt.% of an acrylated polyester compound (D), and

[0061] - one or more pigment(s) (G),

[0062] wherein the wt.% is calculated based upon the solid content of the coating composition excluding any pigment(s).

[0063] A typical pigmented coating composition of the present invention that is substantially free of an acrylated polyester compound (D), has the following composition

[0064] - from 25,0 to 30,0 wt.% of a saturated polyester resin (A)CASE: 11284PFA WO

[0065] - from 2,5 to 3,5 wt.% of an epoxy resin (B)

[0066] - from 4,0 to 4,5 wt.% of a blocked aliphatic isocyanate (C)

[0067] - from 5,0 to 5,5 wt.% of butylated melamine (F), and

[0068] - from 5,5 to 6,5 wt.% of an acrylated epoxy compound (E), and

[0069] - from 50,0 to 55,5 wt.% of one or more pigment(s) (G),

[0070] wherein the wt.% is calculated based upon the solid content of the coating composition. Alternatively, a typical pigmented coating composition of the present invention that is substantially free of an acrylated polyester compound (D), has the following composition

[0071] - from 57,0 to 62,0 wt.% of a saturated polyester resin (A)

[0072] - from 5,5 to 7,5 wt.% of an epoxy resin (B)

[0073] - from 8,5 to 10,5 wt.% of a blocked aliphatic isocyanate (C)

[0074] - from 10,0 to 12,0 wt.% of butylated melamine (F),

[0075] - from 12,5 to 15,0 wt.% of an acrylated epoxy compound (E), and

[0076] - one or more pigment(s) (G),

[0077] wherein the wt.% is calculated based upon the solid content of the coating composition excluding any pigment(s).

[0078] The coating composition of the present invention can be obtained by thoroughly mixing the individual ingredients. It is also possible to make premix of two or more components and mix them in a later stage with the remaining components. This mixing is typically done at room temperature, but if required the mixing can also be done at elevated temperature or under cooling conditions. Care must be taken at elevated temperatures that the curing of the coating is avoided. If necessary, the mixing of the individual ingredients can be done in an inert atmosphere to avoid any degradation of the individual ingredients or the composition as a whole.

[0079] After the mixing of the individual ingredients, the coating composition preferably has the following properties:

[0080] - Solid content of 63 - 67 wt.%

[0081] - Viscosity Cup Ford 4 at 25°C of 130 - 140 s (seconds)

[0082] The present invention also relates to a process for decorating a metal substrate. In this process the coating composition of the present invention is used. The process forCASE: 11284PFA WO

[0083] decorating a metal substrate according to the present invention comprises the following steps:

[0084] - applying to a metal substrate a coating composition according to the present invention,

[0085] - curing the coating composition,

[0086] - applying an ink to the coated metal substrate, and

[0087] - solidifying the ink.

[0088] In one embodiment, the coating is solidified through curing by using heat. Typically, in such process the coating is cured for 5 - 15 minutes at a peak metal temperature in the range from 175 - 200 °C.

[0089] The metal substrate can be a beverage can or any part of a beverage can.

[0090] In another embodiment, the ink is solidified by drying, for example through evaporation of a solvent. It is also possible to cure the ink through radiation, for example UV-radiation.

[0091] The ink that is used for the decoration of the substrate can be any ink known in the art. In view of the printing techniques that are most commonly used for the decoration of cans, preference is given to the use of digital inks, UV-inks or conventional inks.

[0092] Definitions

[0093] The solid content of the coating composition equals CCD / CC (%), wherein CC is the weight of the coating composition as prepared and CCD is the weight of the coating composition after evaporation of all the solvent, for example by heating the coating composition for 30 minutes at 170°C. In a similar way the solid content of the individual components can be determined.

[0094] The solid content of the coating composition excluding any pigment(s) equals CCPF / CC (%) wherein CC is the weight of the coating composition as prepared and CCPF is the weight of all components in the coating composition, but excluding the weight of any pigments that are present, after evaporation of all the solvent(s), for example by heating the coating composition for 30 minutes at 170°C.

[0095] Substantially free means that the particular component is present in a very low amount (less than 0,1 wt.% in a composition) or is not present in the composition.CASE: 11284PFA WO

[0096] The viscosity of the coating composition at 25°C is measured by Cup Ford 4, in accordance with ASTM D1200, in conjunction with ASTM D 333 and ASTM D 365. The viscosity of the individual components is measured at the indicated temperature according to DIN En ISO 3219

[0097] The hydroxyl value is measured in accordance with ASTM D4274.

[0098] The acid value is measured in accordance with ASTM D1639

[0099] The molecular weight of a compound is measured in accordance with the ASTM test method for the particular compound, such as ASTM 4603 for polyester resins. For non-polymeric materials, the molecular weight can be calculated by the skilled person based upon the chemical structure of the compound.

[0100] The epoxy equivalent weight is measured in accordance with ASTM D1652

[0101] The NCO content is measured in accordance with DIN 53185.CASE: 11284PFA WO

[0102] The invention will be further illustrated by the following examples. The invention is however not restricted to these examples.

[0103] EXAMPLES

[0104] In these examples, the following starting materials were used

[0105] Polyester resin

[0106] a saturated polyester resin in a non-aqueous solvent having

[0107] • a solid content of around 60 wt.%

[0108] • a molecular weight between 11000 and 13000 g / mol

[0109] • a viscosity at 25C between 8,0 and 17 Pa.s

[0110] • an acid value between 5 - 10 mg KOH / g

[0111] • a hydroxyl value between 15 - 30 mg KOH / g.

[0112] Epoxy resin

[0113] a bisphenol-A based epoxy resin in a non-aqueous solvent having

[0114] • a solid content of around 75 wt.%

[0115] • an epoxy equivalent weight between 430 - 500 g / eq

[0116] • a viscosity at 25C between 7,5 and 12 Pa.s.

[0117] Isocyanate

[0118] a blocked aliphatic polyisocyanate in a non-aqueous solvent having

[0119] • a solid content of around 75 wt.%

[0120] • a viscosity at 25C between 2 and 4 Pa.s

[0121] • an NCO content between 11 - 12 wt.%.

[0122] Butylated melamine

[0123] a butylated product of a reaction product between melamine and formaldehyde in a non-aqueous solvent having

[0124] • a solid content of around 78 wt.%

[0125] • a molecular weight between 400 and 600 g / mol

[0126] • a viscosity at 25C between 5 and 8 Pa.s

[0127] • an acid value between 0 - 2 mg KOH / g.CASE: 11284PFA WO Acrylated polyester

[0128] an acrylated polyester having

[0129] • a molecular weight between 500 and 1500 g / mol

[0130] • a viscosity at 25C between 0,4 and 0,6 Pa.s

[0131] • an acid value between 0 - 25 mg KOH / g.

[0132] Acrylated epoxy

[0133] an acrylated epoxy compound in a non-aqueous solvent having

[0134] • a solid content of around 79 wt.%

[0135] • a molecular weight between 400 and 600 g / mol

[0136] • a viscosity at 25C between 8 and 14 Pa.s

[0137] • an acid value between 0 - 2 mg KOH / g.

[0138] Example 1 (E1)

[0139] A coating composition was prepared by mixing at room temperature 31,7 pbw of the polyester resin, 35 pbw of titanium dioxide, 2,6 pbw of the epoxy resin, 3,7 pbw of the isocyanate, 4,4 pbw of the butylated melamine, 5 pbw of the acrylated polyester, 12,1 pbw of Nafta Aromatic C9 and 5,5 pbw of butyl glycol.

[0140] Example 2 (E2)

[0141] A coating composition was prepared by mixing at room temperature 31,7 pbw of the polyester resin, 35 pbw of titanium dioxide, 2,6 pbw of the epoxy resin, 3,7 pbw of the isocyanate, 4,4 pbw of the butylated melamine, 5 pbw of the acrylated epoxy, 12,1 pbw of Nafta Aromatic C9 and 5,5 pbw of butyl glycol.

[0142] Comparative example 3 (CE3)

[0143] A coating composition was prepared by mixing at room temperature 34,5 pbw of the polyester resin, 35 pbw of titanium dioxide, 2,8 pbw of the epoxy resin, 3,8 pbw of the isocyanate, 4,8 pbw of the butylated melamine, 13,1 pbw of Nafta Aromatic C9 and 6 pbw of butyl glycol.

[0144] Example 4CASE: 11284PFA WO

[0145] The coating composition E1 and CE3 were applied to a metal substrate and cured for 10 minutes at a peak metal temperature in the range of 180 - 195C, to obtain a dry coating film of 9,0 - 10,0 msi (milligrams per square inch).

[0146] Using an IGT ink testing system, a defined amount of a black UV ink was applied to the coated metal substrates at a pressure of 600N. After the ink was dried, the hiding power was measured using an X-Rite 500 series spectrodensitometer.

[0147] The results of these measurements are presented in Table 1

[0148] Table 1 Hiding power measured (Dy) using the X-Rite spectrodensitometer <

[0149]

[0150] Example 5

[0151] Example 4 was repeated using Ciano UV Ink

[0152] The results of the hiding power measurements are presented in Table 2

[0153] Table 2 Hiding power measured (Dy) using the X-Rite spectrodensitometer <

[0154]

[0155] Example 6

[0156] Example 4 was repeated using black conventional Ink

[0157] The results of the hiding power measurements are presented in Table 3

[0158] Table 3 Hiding power measured (Dy) using the X-Rite spectrodensitometer

[0159]

[0160] Example 7

[0161] Example 4 was repeated using ciano conventional InkCASE: 11284PFA WO

[0162] The results of the hiding power measurements are presented in Table 4

[0163] Table 4 Hiding power measured (Dy) using the X-Rite spectrodensitometer

[0164]

[0165] As can be seen from the measurement results above, using the coating composition of the current invention, about 30% less ink is necessary to achieve the same hiding power, in comparison to the state-of-the-art coating composition of the comparative example.

Claims

CASE: 11284PFA WOCLAIMS1. Coating composition comprising- a polyester resin,- an epoxy resin,- an isocyanate,- an acrylated polyester compound or an acrylated epoxy compound, wherein the acrylated polyester resin is different from the polyester resin or the acrylated epoxy is different from the epoxy resin,- a butylated melamine, and- optionally one or more pigment(s).

2. The coating composition of claim 1 , wherein- the polyester resin is a saturated polyester resin,- the isocyanate is a blocked aliphatic isocyanate, and- the pigment that is optionally present is a white pigment.

3. The coating composition of claim 2, which is substantially free an acrylated epoxy compound, comprising- from 55,0 to 60,0 wt.% of a saturated polyester resin- from 5,0 to 7,0 wt.% of an epoxy resin- from 8,0 to 10,0 wt.% of a blocked aliphatic isocyanate- from 10,0 to 12,0 wt.% of butylated melamine, and- from 15,0 to 17,0 wt.% of an acrylated polyester compound, wherein the wt.% is calculated based upon the solid content of the coating composition excluding any pigment(s).

4. The coating composition of claim 2, which is substantially free of an acrylated polyester compound, comprising- from 57,0 to 62,0 wt.% of a saturated polyester resin- from 5,5 to 7,5 wt.% of an epoxy resin- from 8,5 to 10,5 wt.% of a blocked aliphatic isocyanate- from 10,0 to 12,0 wt.% of butylated melamine, and- from 12,5 to 15,0 wt.% of an acrylated epoxy compound,CASE: 11284PFA WOwherein the wt.% is calculated based upon the solid content of the coating composition excluding any pigment(s).

5. The coating composition of claim 2, which is substantially free of an acrylated epoxy compound, comprising- from 25,0 to 30,0 wt.% of a saturated polyester resin- from 2,5 to 3,5 wt.% of an epoxy resin- from 4,0 to 5,0 wt.% of a blocked aliphatic isocyanate- from 4,5 to 5,5 wt.% of butylated melamine,- from 7,0 to 8,0 wt.% of an acrylated polyester compound, and- from 40,0 to 60,0 wt.% of one or more pigment(s),wherein the wt.% is calculated based upon the solid content of the coating composition.

6. The coating composition of claim 2, which is substantially free of an acrylated polyester compound, comprising- from 25,0 to 30,0 wt.% of a saturated polyester resin- from 2,5 to 3,5 wt.% of an epoxy resin- from 4,0 to 4,5 wt.% of a blocked aliphatic isocyanate- from 5,0 to 5,5 wt.% of butylated melamine, and- from 5,5 to 6,5 wt.% of an acrylated epoxy compound, and- from 40,0 to 60,0 wt.% of one or more pigment(s),wherein the wt.% is calculated based upon the solid content of the coating composition.

7. Process for the decoration of a metal substrate, the process comprising the following steps:- applying to the metal substrate a coating composition according to any of claims 1 - 6,- curing the coating composition,- applying an ink to the coated metal substrate, and- solidifying of the ink.CASE: 11284PFA WO8. The process of claim 7, wherein the metal substrate is a metal can.

9. The process of claims 7 or 8, wherein the ink is a digital ink, a UV-ink, or a conventional ink.

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