RADIATION CURABLE COMPOSITIONS

Abstract

The present invention relates to a radiation curable composition comprising: (I) A radiation curable component comprising a compound having at least one ethylenically unsaturated group and (II) A chlorinated polyester component that is prepared from (A) A polyol component which is substantially free of any Bisphenol A derivative compound and which is substantially free of any cyclic ether polyol compound, said polyol component comprising a polyol compound (Ai) which is cyclic and which has at least two hydroxyl groups, and (B) A polycarboxylic acid component comprising a compound (Bi) having at least one chlorine group and at least two carboxyl groups, (C) optionally at least one monoalcohol compound, (D) optionally at least one monocarboxylic acid compound, (III) optionally at least one polycarboxylic acid compound substantially free of chlorine groups.

Claims

1. A radiation curable composition comprising (I) A radiation curable component comprising a compound having at least one ethylenically unsaturated group and (II) A chlorinated polyester component that is prepared from (A) A polyol component which is substantially free of any Bisphenol A derivative compound and which is substantially free of any cyclic ether polyol compound, said polyol component comprising a polyol compound (Ai) which is cyclic and which has at least two hydroxyl groups, and (B) A polycarboxylic acid component comprising a compound (Bi) having at least one chlorine group and at least two carboxyl groups, (C) optionally at least one monoalcohol compound, (D) optionally at least one monocarboxylic acid compound, (E) optionally at least one polycarboxylic acid compound substantially free of chlorine groups, and (III) Optionally an additional radiation curable component comprising at least one oligomeric compound having at least two radiation curable ethylenically unsaturated groups.

2. The radiation curable composition according to claim 1, wherein the polyol component (A) additionally comprises an acyclic aliphatic polyol compound (Aii), optionally including at least one ether function.

3. The radiation curable composition according to claim 1, wherein the polyol component (A) comprises at least 5% by weight of one or more cyclic polyol(s) (Ai).

4. The radiation curable composition according to claim 3, wherein the polyol component (A) comprises at least 20% by weight of one or more cyclic polyol(s) (Ai).

5. The radiation curable composition according to claim 1, wherein the cyclic polyol compound (Ai) comprises 1, 4-cyclohexanedimethanol (CHDM).

6. The radiation curable composition according to claim 1, wherein the compound (Bi) comprises chlorendic acid.

7. The radiation curable composition according to claim 6, wherein the polycarboxylic acid compound (E) comprises phtalic acid.

8. The radiation curable composition according to claim 1, wherein the equivalent ratio of hydroxyl groups to carboxyl groups exceeds 1.0.

9. The radiation curable composition according to claim 1, wherein the chlorinated polyester (II) has a number average molecular weight comprised between 500 and 5000 Daltons.

10. The radiation curable composition according to claim 1, wherein the ethylenically unsaturated compound (I) comprises at least one (meth) acrylated compound selected from di(meth)acrylates and/or tri(meth)acrylates and/or tetra(meth)acrylates and or penta(meth)acrylates and/or hexa(meth)acrylates.

11. The radiation curable composition according to claim 1 wherein the chlorine content of the chlorinated polyester (II) is comprised between 5 and 75%, preferably from 10 to 30%

12. The radiation curable composition according to claim 1, comprising at least one additive chosen amongst the following list: photoinitiator, pigment, wetting agent, pigment dispersant, leveling agent, inhibitor, dispersing agent, stabilizer, antifoam agent, filler.

13. The radiation curable composition according to claim 1, wherein the oligomeric compound (III) has a backbone comprising one or more of the following groups: ester, ether, urethane, epoxy, acrylic, amino group.

14. An adhesive, coating, ink or varnish composition comprising a radiation curable composition according to claim 1.

15. An article coated, partially or entirely, with a radiation curable composition according to claim 14.

Description

EXAMPLE 1 (CHDM, CI CONTENT 24.6%)

[0178] 152 g Diethylene glycol, 246 g Phtalic anhydride, 618 g Chlorendic anhydride and 466 g Cyclohexane dimethanol were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and an distillation column. The mixture was then heated to a temperature of about 165 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 50 mg KOH/g (DIN_EN_ISO_2114), a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value is below 20 mg KOH/g (typically after 5-12 hours reaction), cooled down to 70 C. by diluting in 950 gram reactive monomer (TMPTA). 1425 g of the undiluted polyester was unloaded and recharged while diluting in 950 gram reactive monomer (TMPTA). The inert polyester thus obtained had a hydroxyl value of 130 mg KOH/g. The Mw of the polyester thus obtained was 1320 g/mol. The viscosity of the diluted polyester had a value of 1310 mPa s (measured with MCR equipment at 60 C.).

EXAMPLE 2 (CHDM, HIGHER MOLECULAR WEIGHT, CI CONTENT 17%)

[0179] 199 g Diethylene glycol, 346 g Phtalic anhydride, 325 g Chlorendic anhydride and 236 g Cyclohexane dimethanol were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and an distillation column. The mixture was then heated to a temperature of about 177 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 50 mg KOH/g (DIN_EN_ISO_2114), a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value is below 20 mg KOH/g (typically after 9-16 hours reaction), cooled down to 70 C. and 1048 g of the undiluted polyester was unloaded and recharged while diluting in 695 gram reactive monomer (TMPTA).

[0180] The inert polyester thus obtained had a hydroxyl value of 50 mg KOH/g. The Mw of the polyester thus obtained was 2685 g/mol. The viscosity of the diluted polyester had a value of 1750 mPa s (measured with MCR equipment at 60 C.).

EXAMPLE 3 (CHDM, HIGHER MOLECULAR WEIGHT, CI CONTENT 25.7%)

[0181] 380 g Diethylene glycol, 480 g Phtalic anhydride, 1000 g Chlorendic anhydride and 450 g Cyclohexane dimethanol were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and an distillation column. The mixture was then heated to a temperature of about 177 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 50 mg KOH/g (DIN_EN_ISO_2114), a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value is below 20 mg KOH/g (typically after 9-16 hours reaction), cooled down to 70 C. and 2203 g of the undiluted polyester was unloaded and recharged while diluting in 1468 gram reactive monomer (TMPTA).

[0182] The inert polyester thus obtained had a hydroxyl value of 60 mg KOH/g. The Mw of the polyester thus obtained was 2120 g/mol. The viscosity of the diluted polyester had a value of 1820 mPa s (measured with MCR equipment at 60 C.).

COMPARATIVE EXAMPLE 1 (1R, COMPARATIVE, HBPA, NO CHDM, CI CONTENT 20.3%, SIMILAR TO EBECRYL436 POLYESTER ACRYLATE)

[0183] 78.4 g Diethylene glycol, 127.6 g Phtalic anhydride, 319 g Chlorendic anhydride and 403.8 g Hydrogenated Bisphenol A were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and a distillation column. The mixture was then heated to a temperature of about 165 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 60 mg KOH/g a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value is below 50 mg KOH/g (typically after 5-12 hours reaction), cooled down to 70 C. 892 g of the undiluted polyester was unloaded and recharged while diluting in 610 g reactive monomer (TMPTA).

[0184] The inert polyester thus obtained had a hydroxyl value of 140 mg KOH/g. The Mw of the polyester thus obtained was 920 g/mol. The viscosity of the diluted polyester had a value of 1453 mPa s (measured with MCR equipment at 60 C.).

COMPARATIVE EXAMPLE 2 (2R, COMPARATIVE, ISOSORBIDE, NO CHDM)

[0185] 303 g Diethylene glycol, 494 g Phtalic anhydride, 1235 g Chlorendic anhydride and 945 g Isosorbide were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and an distillation column. The mixture was then heated to a temperature of about 165 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 50 mg KOH/g a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value is below 20 mg KOH/g (typically after 5-12 hours reaction), cooled down to 70 C. and 2843 g of the undiluted polyester was unloaded and recharged while diluting in 1900 g reactive monomer (TMPTA).

[0186] The inert polyester thus obtained had a hydroxyl value of 160 mg KOH/g. The Mw of the polyester thus obtained was 1200 g/mol. The viscosity of the diluted polyester was 1420 mPa s (measured with MCR equipment at 60 C.).

COMPARATIVE EXAMPLE 3 (3R, COMPARATIVE, NO BPA, NO CHDM)

[0187] (no cyclic polyol) 500 g Ethylene glycol, 81 g Trimetylolpropane, 706 g Chlorendic anhydride, 393 g isophtalic acid and 471 g phtalic acid were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and a distillation column. The mixture was then heated to a temperature of about 165 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 50 mg KOH/g a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value was below 25 mg KOH/g (typically after 5-12 hours reaction), cooled down to 70 C. and 2068 g of the undiluted polyester was unloaded and recharged while diluting in 1300 gram reactive monomer (TMPTA).

[0188] The inert polyester thus obtained had a hydroxyl value of 112 mg KOH/g. The Mw of the polyester thus obtained was 1810 g/mol. The viscosity of the diluted polyester was 1571 mPa s measured with MCR equipment at 60 C.).

COMPARATIVE EXAMPLE 4 (4R, COMPARATIVE, NON-CHLORINATED, NO CHDM)

[0189] 784 g Diethylene glycol, 2453 g Phtalic anhydride and 4000 g Hydrogenated Bisphenol A were charged to a double-wall glass reactor equipped with a stirrer, a thermocouple attached to a thermoregulator, a gas inlet tube, a connection to vacuum and a distillation column. The mixture was then heated to a temperature of about 165 C. The polycondensation was continued until no more water is distilled over. Reduced pressure was applied gradually reaching a vacuum of 900 mmHg while the acid value was decreased. Upon reaching an acid value of 65 mg KOH/g a correction was made in either acid or diol based on delta between acid value and Hydroxyl value (DIN_53240_T2) when acid value was below 48 mg KOH/g (typically after 5-12 hours reaction), cooled down to 70 C. and 8870 g of the undiluted polyester was unloaded and recharged while diluting in 5950 gram reactive monomer (TMPTA).

Formulation:

[0190] The pigment paste was prepared as follows: 61 wt % of the binder prepared as mentioned above (diluted polyester) was mixed with further TMPTA (8 wt %) and with 30 wt % of pigment (Special Black 250 of Degussa) and 1 wt % of additives (stabilizer ADDITOL S130 from allnex).

[0191] The paste was grinded on triple roll mill until the right grinding gauge of 7 Hegman Units or 12.7 Microns was obtained.

[0192] The ink was prepared from this pigment paste (72%) by mixing further with the binder (19%), with photoinitiator (8%) and diluting monomer (1% TMPTA) to achieve the target viscosity of about 100 Pa s at 25 C.

[0193] Photoinitiator mix composition: 30% Speedcure ITX (isopropylthioxanthone) from Lambson; 25% Speedcure EDB (Ethyl-4-dimethylamino benzoate) from Lambson; 25% Speedcure EHA (2-Ethylhexyl 4-(Dimethylamino)benzoate) from Lambson; 5% ADDITOL PBZ from allnex.

Application Results

[0194]

TABLE-US-00001 TABLE 1 cure speed 1R 2R Example 1 (HBPA) 3R (Isosorbide) (CHDM) Visco 2.5 1/s 118 133 120 107 Visco 100 1/s 39 32.2 34.1 34 SI 2.5-100 3.0 4.1 3.5 3.1 Density - 1.5 g/m.sup.2 2.15 2.08 2.01 2.10 Gloss - 1.5 g/m.sup.2 23 22 20 21 60 Cure speed 140 20 2 20 2 20 20 W/cm

[0195] The cure speed for the example according to the invention is higher than for isosorbide and for the industry standard. HBPA comparative example also provides high cure speed. This is advantageous as the composition only need one pass under the UV lamp instead of two, which permits money and time savings.

TABLE-US-00002 TABLE 2 Tack results 1R 2R (HBPA) 3R (Isosorbide) Example 1 Tack @ 50 m/min 320 225 240 220 Tack @ 100 m/min 525 415 380 325 Tack @ 150 m/min 680 540 470 425 Tack @ 200 m/min 810 640 570 510 Tack @ 250 m/min >830 720 640 580 Tack @ 300 m/min >830 760 700 640 Tack @ 350 m/min >805 760 695 655

[0196] Tack values for isosorbide comparative and for the example according to the invention are lower and more stable especially compared to HBPA based comparative example. For all measurements, the tack value obtained with the example is lower, thus better, than each of the comparatives.

TABLE-US-00003 TABLE 3 Adhesion on plastics at 1 30 m/min and 3 30 m/min 1R 2R (HBPA) 3R (Isosorbide) Example 1 treatment no corona treatment Curing (30 1 3 1 3 1 3 1 3 m/min) - Substrates PET 1 5 5 5 5 5 5 5 BOPP 5 5 4+ 4+ 4+ 4+ 5 5 PVC 4+ 4+ 1 1 1 4+ 5 5

[0197] With curing 130 m/min: [0198] on PET: bad adhesion for Comparative example with HBPA but OK for other compositions. [0199] On PVC, bad adhesion was obtained for the industry standard and for Isosorbide. Good adhesion was obtained for Comparative example with HBPA and very good adhesion for the example according to the invention.

[0200] With curing 330 m/min: [0201] Still no adhesion on PVC for the industry standard and for Isosorbide, [0202] Adhesion for on PVC good for Comparative example with HBPA and very good for the example according to the invention.

[0203] For all tests conducted, the example according to the invention had always provided the most favorable results compared to the 3 other samples.

TABLE-US-00004 TABLE 4 delamination results Delamination in function of the % Cl 1 Layer 2 Layers Fmax Fmax 4R: Comparative example containing 0% Cl <1 <1 calculated on undiluted Polyester 1R Comparative example containing 20.3% 3.55 2.98 Cl calculated on undiluted Polyester Example 1: Resin containing 24.7% Cl 2.20 3.09 calculated on undiluted Polyester Example 2: Resin containing 17% Cl 2.70 2.69 calculated on undiluted Polyester Example 3: Resin containing 25.7% Cl 4.88 3.10 calculated on undiluted Polyester

[0204] Bond-strength is the force (N) per unit area required to separate two adjacent layers of a package. Bond strength value was tested using a dynamometer.

[0205] A printed sample was prepared by putting the composition, formulated as an ink as described above, according to example 1, 2, 3 or comparative example 1 or 4 onto a substrate (polypropylene), using a hand coater, wet deposit thickness=2 micron and UV curing the applied layer. A second layer (2 micron wet deposit thickness) was applied on some samples, and UV cured.

[0206] A counter-substrate (Polyethylene) was provided with a layer of an adhesive using a hand coater and subsequently dried. The printed substrate was applied onto the adhesive layer, and the substrate and counter substrate were pressed against each other using rollers, thus forming a laminate.

[0207] The laminated printed sample was stored for 7 days at 25 C. to allow adhesive curing before delamination evaluation.

[0208] A sample was cut out of the laminate composition and was placed between two jaws. The sample was drawn out and the substrate was separated from the counter-substrate. At a speed of 200 mm/min, the bond strength value was determined, and the force (in N) needed to delaminate the sample was measured.

[0209] The results obtained with Comparative example 4R show that a non-chlorinated polyester does not provide enough adhesion.

[0210] The results obtained with comparative 1R show that a non BPA containing sample according to the invention can achieve similar results as commercial BPA containing sample and even better as shown in example 3.