AMINO (METH)ACRYLATES

Abstract

Materials of the invention are suitable for use in coating compositions, inks, paints, varnishes, adhesives, for the making of gel coats, composites, molding compositions or 3D articles. Materials of the invention are in particular suitable as surface cure boosterin UV and UV LED applications.

Claims

1. A radiation curable addition product that contains (meth)acrylic groups and that is prepared from: (i) at least one (meth)acrylated compound (A) which comprises at least one (meth)acrylated compound (A-I) that contains 3 or more (meth)acrylic ester groups per molecule; (ii) at least one amino compound (C) that contains one secondary amino group and no primary amino group; (iii) at least one amino compound (B) which comprises at least one amino compound (B1) that contains one primary amino group and at least one tertiary amino group; and, optionally, (iv) the at least one (meth)acrylated compound (A) further comprises at least one (meth)acrylated compound (A-II) that contains 2 (meth)acrylic ester groups per molecule; (v) the at least one amino compound (B) further comprises at least one amino compound (B2) that is selected from (B2-1) amino compounds that contain one primary amino group and/or from (B2-2) amino compounds that contain two secondary amino groups, which amino compound (B2) is different from amino compounds (B1), wherein the nitrogen content of the radiation curable addition product is at least 1.2 meq/g; and the average (meth)acrylate functionality per mole of the addition product is at most 2.

2. The (meth)acrylated radiation curable addition product according to claim 1, prepared from an amino component (B) that comprises relative to the total weight of amino compounds (B): from 30 to 100 wt % of one or more compounds (B1), and from 0 to 70 wt % of one or more compounds (B2-1) and/or (B2-2).

3. The (meth)acrylated radiation curable addition product according to claim 1, prepared from an (meth)acrylated compound (A) that comprises relative to the total weight of (meth)acrylated compounds (A): from 50 to 100 wt % of one or more compounds (A-I), and from 0 to 50 wt % of one or more compounds (A-II).

4. The (meth)acrylated radiation curable addition product according to claim 1, wherein the molar ratio of amino compounds (B1+B2) relative to (meth)acrylated compounds (A) is from 0.1 to 0.8.

5. The (meth)acrylated radiation curable addition product according to claim 1, wherein compounds (A) are selected from (meth)acrylic esters (A1), polyether (meth)acrylates (A2), polyester (meth)acrylates (A3), epoxy (meth)acrylates (A4) and/or (poly)urethane (meth)acrylates (A5).

6. The (meth)acrylated radiation curable addition product according to claim 1, wherein compounds (B1) are selected from selected from N,N-dialkyl-diaminoalkanes (B1-1) such as DMAPA.

7. The (meth)acrylated radiation curable addition product according to claim 1, wherein compounds (B2) are selected from ethanolamine, isopropanolamine, 2-amino-2-methyl-1-propanol, and mixtures thereof.

8. The (meth) acrylated radiation curable addition product according to claim 1, wherein compounds (C) respond to the formula:
R′—NH—R wherein R′ is an alkyl, optionally substituted by hydroxy, alkoxy, tertiary amine and/or aryl, and, R is an alkyl, optionally substituted by hydroxy, alkoxy, tertiary amine and/or aryl, with the proviso that R′ and R may be linked together in order to form a ring.

9. The (meth)acrylated radiation curable addition product according to claim 1, wherein compounds (C) is selected from the group consisting of: diethylamine, di n-propylamine, di n-butylamine, di n-hexylamine, di 2-ethylhexylamine, di cyclohexylamine, di n-octylamine, di n-dodecylamine, di 2-(2-aminoethoxy)ethanol, di 5-aminopentanol, diethanolamine, di iso-propanolamine, piperidine and any mixtures thereof.

10. The (meth)acrylated radiation curable addition product according to claim 1, wherein no compounds (B2) are used as reagents.

11. The (meth)acrylated radiation curable addition product according to claim 1, wherein no compounds (A-II) are used as reagents.

12. The (meth)acrylated radiation curable addition product according to claim 1, having a calculated number average molecular weight of between 400 and 3.500 Dalton.

13. The (meth)acrylated radiation curable addition product according to claim 1, having a viscosity at 25° C. of from 50 to 100.000 mPa.Math.s.

14. A radiation curable composition comprising at least 5 wt % of one of more (meth)acrylated radiation curable addition products according to claim 1.

15. The radiation curable composition according to claim 13, further comprising at least 1 wt % of one or more (meth)acrylated compounds (D) that are different from the (meth)acrylated radiation curable addition products.

16. The radiation curable composition according to claim 14, which is an ink, a paint, a varnish, a coating composition or an adhesive.

17. A process for coating an article or substrate with a radiation curable composition according to claim 14 comprising the steps of: (a) providing a radiation curable composition according to claim 14, (b) applying said composition onto a surface, and (c) irradiating the surface with actinic radiation using e.g. an UV LED lamp emitting at 365, 385, 395 or 405 nm.

18. The use of a (meth)acrylated radiation curable addition product according to claim 1.

Description

EXAMPLES

[0143] The following generic processes were used herein to prepare the adducts of amines and di(meth)acrylates specified herein:

Example 1

[0144] A reaction vessel was charged with 1144 g EBECRYL® 40 (a tetrafunctional polyether acrylate commercially available from Allnex) (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (EBECRYL® 40), amino compounds B (3-(dimethylamino)-1-propylamine (DMAPA)) and amino compounds C (Dipropylamine (DPA)). The reaction mixture was heated and the temperature was set at 60° C. 425 g (4.2 moles) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was further reacted for 2 hrs at 60° C. After this 76.6 g of dimethylamine propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Example 2

[0145] A reaction vessel was charged with 1144 g EBECRYL® 40 (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (EBECRYL® 40), amino compounds B (3-(dimethylamino)-1-propylamine) and amino compounds C (Dipropylamine). The reaction mixture was heated and the temperature was set at 60° C. 425 g (4.2 moles) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was further reacted for 2 hrs at 60° C. After this 153.3 g of 3-(dimethylamino)-1-propylamine (1.5 moles) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Example 3

[0146] A reaction vessel was charged with 944 g TMP(OE).sub.4TA (ethoxylated trimethylolpropane triacrylate) (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (TMP(OE).sub.3TA), amino compounds B (3-(dimethylamino)-1-propylamine) and amino compounds C (Dipropylamine). The reaction mixture was heated and the temperature was set at 60° C. 212.5 g (2.1 moles) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was further reacted for 2 hrs at 60° C. After this 76.6 g of 3-(dimethylamino)-1-propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Example 4

[0147] A reaction vessel was charged with 592 g TMPTA (trimethylolpropane triacrylate) (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (TMPTA), amino compounds B (3-(dimethylamino)-1-propylamine) and amino compounds C (Dipropylamine). The reaction mixture was heated and the temperature was set at 60° C. 212.5 g (2.1 moles) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was further reacted for 2 hrs at 60° C. After this 76.6 g of 3-(dimethylamino)-1-propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Example 5

[0148] A reaction vessel was charged with 296 g TMPTA (1 mole) and 242 g DPGDA (dipropylene glycol diacrylate) (1 mole) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (TMPTA and DPGDA), amino compounds B (3-(dimethylamino)-1-propylamine) and amino compounds C (Dipropylamine). The reaction mixture was heated and the temperature was set at 60° C. 101.2 g (1 mole) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was further reacted for 2 hrs at 60° C. After this 76.6 g of 3-(dimethylamino)-1-propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Comparative Example 1 (EBECRYL® 40 and Reaction with DMAPA but without DPA)

[0149] A reaction vessel was charged with 1144 g EBECRYL® 40 (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (EBECRYL® 40) and amino compounds B (3-(dimethylamino)-1-propylamine). The reaction mixture was heated and the temperature was set at 60° C. 76.6 g of 3-(dimethylamino)-1-propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%.

Comparative Example 2 (EBECRYL® 40 and Reaction with DMAPA but without DPA)

[0150] A reaction vessel was charged with 1144 g EBECRYL® 40 (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (EBECRYL® 40) and amino compounds B (3-(dimethylamino)-1-propylamine). The reaction mixture was heated and the temperature was set at 60° C. 153.3 g of 3-(dimethylamino)-1-propylamine (1.5 moles) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature. After 3 hours reaction the reaction mixture gelled.

Comparative Example 3 (EBECRYL® 40 and Reaction with DPA but without DMAPA)

[0151] A reaction vessel was charged with 1144 g EBECRYL® 40 (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (EBECRYL® 40) and amino compounds C (Dipropylamine). The reaction mixture was heated and the temperature was set at 60° C. 425 g (4 moles) of dipropylamine was added dropwise so that the temperature was not exceeding 75° C. Once the addition was completed, the mixture was left to further maturate at 60° C. until the free amino concentration was lower than 0.02%.

Comparative Example 4 (Only a 2 Functional Acrylate DPGDA)

[0152] A reaction vessel was charged with 484 g DPGDA (2 moles) as well as 250 ppm of stabilizer relative to total amount of (meth)acrylate compounds A (DPGDA) and amino compounds B (3-(dimethylamino)-1-propylamine). The reaction mixture was heated and the temperature was set at 60° C. 76.6 g of 3-(dimethylamino)-1-propylamine (0.75 mole) was added dropwise so that the temperature did not exceed 75° C. Once the addition was completed, the reaction temperature was increased to 80° C. and left to maturate at this temperature until the free amino concentration was lower than 0.02%

TABLE-US-00001 TABLE 1 Characterization of the amino(meth)acrylates prepared according to the invention Ex 1 Ex 2 Ex 3 Ex 4 Ex 5 EBECRYL ® 40 1144*    1144 TMP(OE).sub.4TA 944 TMPTA 592 296 DPGDA 242 dimethylamino 76.6  153.3 76.6 76.6 76.6 propyl amine Dipropylamine 425    425 212.5 212.5 106.25 h.sup.25° C., mPa .Math. s 700    854 504 1344 529 nitrogen content, 3.5 4.2 2.9 4.2 3.5 meq/g (meth)acrylate 1.4 0.5 2 2.7 3.4 content, meq/g *Amounts are in grams, unless specified otherwise.

TABLE-US-00002 TABLE 2 Characterization of comparative examples Comp Comp Comp Comp Ex 1 Ex 2 Ex 3 Ex 4 EBECRYL ® 40 1144 1144 1144 TMP(OE).sub.4TA TMPTA DPGDA 484 3-(dimethylamino)- 76.6 153.3 76.6 1-propylamine Dipropylamine 425 h.sup.25° C., mPa .Math. s 564 gelled 202 165 nitrogen content, 1.2 — 2.7 2.7 meq/g (meth)acrylate 5.3 — 2.4 4.5 content, meq/g

[0153] Examples 1,3,4 include reactions of a 4-functional (EBECRYL® 40) and 3-functional (TMP(OE).sub.4TA and TMPTA) acrylate compound with dipropylamine and 0.75 mole of 3-(dimethylamino)-1-propylamine. Example 2 is similar to example 1, except that a higher amount of 3-(dimethylamino)-1-propylamine is used (1.5 moles). In example 5 a mixture of a 2- and 3 functional acrylate compound is used. All amino acrylates of examples 1-5 have an average acrylate functionality below 2.

[0154] Comparative examples 1 and 3 are similar to example 1, but without respectively dipropylamine and dimethylaminopropylamine. Comparative example 2 is similar to example 2 but without dipropylamine. Note that during the synthesis this product gelled. Comparative example 4 is prepared with only a 2 functional acrylate monomer (DPGDA).

Application Examples

1. Formulation for UV LED Curable Coatings

[0155] Radiation curable compositions were prepared based on the formulations described in Tables 3 and by adding 5 wt % of commercial IRGACURE® TPO-L photoinitiator from IGM (ethyl (2,4,6-trimethylbenzoyl) phenyl phosphinate).

[0156] Cured films (20 μm layers) on coated paper were prepared using a bar coater and curing was done under ambient atmosphere by UV LED with an air-cooled Phoseon Firejet, with a peak irradiance of 8 W/cm.sup.2 at 365 nm wavelength (LED365). The distance of lamp to substrate is 1 cm.

[0157] The cure speed was determined to be the maximal belt speed under a given lamp—in this case LED365—giving a full cured film. Through cure of the film is investigated by acetone double rubs (ADR) with a wad drenched in acetone. A minimum of 50 ADR is required for a fully cured coating with optimum performance. The surface cure aspect of the film is assessed by the fingernail mar and graphite test. The graphite test is carried out by putting some graphite carbon black (Pencil No. 2) onto the coated surface and rubbing with a finger and then with a cotton swab. As long as a black trace is left on the coated surface, the film is not fully cured and passed again under the LED365. The fingernail mar test is carried out by marring the surface with the nail of the finger. If a mark is left behind on the surface, the surface cure is not complete and passed again under the LED365. A fully cured film is not visually affected by this test.

[0158] Minimum cure dose: is the minimal UV(-A) energy required to cure a 20 μm coating that withstands a minimum of 50 acetone double rubs (ADR) and passes the graphite test and fingernail mar test. The lower the dose to cure the coating, the better is the reactivity of the resin. The minimum cure dose corresponds to the cure speed for a given UV light source. The UV Energy dose is automatically derived from the measured UV irradiance (W/cm.sup.2) with the UV Power Puck® II radiometer and the value for the UVA (320-390 nm) zone is recorded in the table.

TABLE-US-00003 TABLE 3 Examples and Comparative examples formulation Comp. Comp. Comp. Ex F1 Ex F2 Ex F3 Ex F4 Ex F5 Ex F1-R Ex F2-R Ex F3-R Diacrylate ester of a 13 13 13 13 13 13 13 13 bisphenol A epoxy resin Tripropylene glycol diacrylate 33 33 33 33 33 33 33 33 Trimethylolpropane diacrylate 33 33 33 33 33 33 33 33 Amino acrylate of Ex 1 15 Amino acrylate of Ex 2 15 Amino acrylate of Ex 3 15 Amino acrylate of Ex 4 15 Amino acrylate of Ex 5 15 Comp Example 1 15 Comp Example 3 15 Comp Example 4 15 TPO-L 3 3 3 3 3 3 3 3 DETX 3 3 3 3 3 3 3 3 Cure speed (m/min) 37.5 37.5 35 27.5 25 5 × 5 27.5 20 Min. cure dose (mJ/cm.sup.2) 250 250 270 350 380 9315 350 480

[0159] Above Table 3 clearly shows that higher reactivity is achieved with Examples F1 and F2, both based on a combination of DMAA and DPA, compared to comparative examples F1-R and F2-R based on the same acrylate but where respectively no DPA and DMAPA are used. Example F 5, composed of a mixture of a di- and trifunctional acrylate monomer and where overall acrylate functionality is reduced to 2 by reaction with DPA shows a higher reactivity compared to Comp example F3-R where only a difunctional acrylate monomer DPGDA is used.

2. Formulation for UV Curable Cyan Flexo Ink

[0160] The pigment paste was prepared as follows: 51 wt % of the binder polyester acrylate (EBECRYL® 452 (commercial polyester acrylate from allnex) was mixed with 40 wt % of pigments and 9 wt % of additives (Table 4). In particular 51 g of the binder was blended at 25° C. with 1 g of Additol® S130 (in-can stabilizer from Allnex), 3.7 g of SOLSPERSE® 39000 (a 100% active polymeric dispersant from Lubrizol), 4.3 g of SOLSPERSE® 5000 premix (1.3 g SOLSPERSE® 5000 from Lubrizol grinded in 3.0 g commercial polyester acrylate from allnex) and 40 g of Pigment SPECTRA PAC-C Blue 15:4 (from Sun Chemical Corp.). The paste was grinded on triple roll mill until the right grinding gauge was obtained.

[0161] The ink was prepared from this pigment paste by diluting further with diluting monomers, example 3 of the current invention and photoinitiator to achieve the target viscosity. In particular cyan inks were prepared by blending at 25° C. 22 g of EBECRYL® 145 (two functional diluting acrylate from allnex), 27 g of PETIA (blend of 3 and 4 functional diluting acrylates from allnex), 6 g of a photoinitiator mix (composition: 50% IRGACURE® TPO-L from IGM, and 50% Speedcure® DETX (2,4-diethylthioxanthone from Lambson), and 45 g of the pigment paste.

TABLE-US-00004 TABLE 4 Pigment paste and UV ink formulation Comp. Comp. Ex Ex Ex F4-R F5-R F6 Polyester acrylate (D1) 51 51 51 S39000 3.7 3.7 3.7 S5000 (paste0.3%) 4.3 4.3 4.3 S130 1 1 1 15:4 PAC-C blue 40 40 40 Grinding of pigment paste triple roll - 2 pass Propoxylated Neopentylglycol Diacrylate (D2) 22 12 12 Pentaerythritol tri- and tetraacrylate 27 27 27 mixture (D2′) Amino acrylate of Comp Ex1 10 Amino acrylate of Ex 3 — 10 PI mix 6 6 6 PAC-C paste at 40% 45 45 45

[0162] Rheology and reactivity of the obtained ink formulations were measured. A comparison was made between Formulation Example F6, a Comparative Formulation Example F4-R which is a flexo ink formulation based on a comparable formulation lacking an amino acrylate according to the invention, and a Comparative Formulation Example F5-R where the amino acrylate is the one from Comparative Example 1. Results are summarized in Table 5 below.

[0163] Application of the radiation curable compositions: The compositions above-described were applied onto C58 (BOPP film without adhesion primer) with a K303 Multicoater equipped with a flexo printing head and a 200 lines/inch @ 100% flexo plate (RK Print Coat Instruments Ltd., UK). This configuration allowed obtaining ca. 4 g/m.sup.2 coatings with reproducibility better than 5%. The coatings were cured under ambient atmosphere by UV LED with LED365 (as described above) at the maximum line speed allowing obtaining a dry surface evaluated with the graphite test. Results are summarized in Table 5 below.

TABLE-US-00005 TABLE 5 Evaluation of the ink properties Comp. Comp. Ex Ex Ex F4-R F5-R F6 Rheology, cone plate, 25° C., Kp50 0.1 to 2500 s−1 0.1 s−1 (*) 803 634 877 2.5 s−1 572 538 746 2500 s−1 439 395 539 SI 2.5-2500 s−1 1.83 1.60 1.63 Reactivity on C58, LED365, printing proofer, 200 lines 5 × 5 m/min 5 × 5 m/min 5 m/min (*) zero viscosity

[0164] This table shows that compositions according to the present invention permit to obtain inks with an improved reactivity compared to Comp. Ex F4-R where no amino acrylate is added, but also compared to formulations using amino acrylates from Comp Ex 1 (Comp. Ex F5-R). Moreover, the amino acrylates according to the invention do not significantly impact the ink formulation rheology, compared to inks without amino acrylates.

[0165] Rheology (viscosity, shortness index): is measured using a cone and plate type rheometer MCR100 (Paar-Physica) following ISO 3219. The measurement geometry for measuring the (flexo) inks of the inventions was of a diameter of 50 mm and an angle of 1° for the cone. The measurement was a flow curve in controlled shear rate ranging from D=0 s-1 (zero viscosity), D=2.5 s-1 to D=2500 s-1 at 25° C.