RHEOLOGY MODIFIER AND COMPATIBILIZER

Abstract

The invention pertains to a comprising: a first resin and a second resin; and/or an adduct of a first resin and a second resin; and/or a first resin or second resin and a catalyst; and a polymeric particle having an average particle size of less than 100 micron, wherein the second resin and/or an adduct of a first resin and a second resin is present in an amount of at least 20 wt %, based on the total weight of the composition and wherein the polymeric particle has a glass transition temperature above the curing temperature.

Claims

1. A coating composition comprising: a first resin and a second resin; and/or an adduct of a first resin and a second resin; and/or a first resin or second resin and a catalyst; and a polymeric particle having an average particle size of less than 100 micron, wherein the second resin and/or an adduct of a first resin and a second resin is present in an amount of at least 20 wt %, based on the total weight of the composition, and wherein the polymeric particle has a glass transition temperature above the curing temperature.

2. The composition according to claim 1, wherein the coating composition is suitable for food contact.

3. The composition according to claim 1, wherein the first resin is a polyol.

4. The composition according to claim 1, wherein the second resin is an aminoplast.

5. The composition according to claim 1, wherein the polymeric particle is a thermoplastic microsphere.

6. The composition according to claim 1, wherein the polymeric particle has an average particle size of less than 100 micron.

7. The composition according to claim 1, further comprising a solvent comprising at least one functional group and capable of reacting with the second resin.

8. The composition according to claim 1, wherein the functional group of the first resin is at least one selected from a hydroxyl and a carboxylic acid.

9. A coated substrate comprising: a substrate; and a cured coating composition applied to at least part of the substrate, the coating composition being in accordance with claim 1.

10. The coated substrate according to claim 9, wherein the substrate is a metal.

11. The coated substrate according to claim 9, wherein the coated substrate is a food or beverage container.

12. The coated substrate according to claim 11, wherein the coated substrate is an internal and/or external side of the container.

13. A process for preparing a coated substrate comprising: (a) applying the coating composition according to claim 1 to a substrate; and (b) curing the coating composition.

14. The process of claim 13 further comprising the step of shaping the coated substrate to a food or beverage container.

15. The coated substrate of claim 10, wherein the metal comprises aluminum or steel.

Description

EXAMPLES

Example 1

[0093] A typical water-based over varnish commercialized by the Applicant under the brand name NovoShield 4718E is thoroughly mixed with 0.1%, 0.2% and 0.5% expandable microspheres with a maximum expansion to 20 micron.

[0094] The mixtures have been applied on a 33 cl aluminum beer and beverage can, provided with black, red and green ink supplied by Sun Chemical.

[0095] After thermal curing in a box oven at 200° C. for four minutes, film weights have been checked (approx. 100 mg dry). All cans show very good abrasion resistance, show matt effect with a haptic touch. All treated cans passed pasteurization (30 minutes at 82° C.) and no adhesion loss was observed.

Example 2

[0096] A typical high solids-based retort-sterilizable over varnish commercialized by the Applicant under the brand name NovoShield 5101 is thoroughly mixed with 0.2% expandable microspheres with a maximum expansion to 20 micron.

[0097] The mixture has been applied on a 33 cl aluminum beer and beverage can, provided with black, red and green retortable ink supplied by Sun Chemical.

[0098] After thermal curing in a box oven at 200° C. for four minutes, film weights have been checked (approx. 120 mg dry). The can shows very good abrasion resistance, shows matt effect with a haptic touch. The treated can passed sterilization (60 minutes at 127° C.) and no adhesion loss was observed.

Example 3

[0099] A standard water-based gloss over varnish, NovoShield 4719 (40% solids), is mixed with 0.5% of a thermally expandable microsphere (initial particle size 10-15 micron, thermal expansion between 125 and 175° C., maximum expansion to 40 micron).

[0100] A bright, washed 33 cl aluminum can is provided with 300 mg wet varnish through a roll coater system. The can is cured for 3 minutes at 190° C. in a box oven. The can is allowed to cool down to room temperature. Another aluminum can is treated in the same way with NovoShield 4719. The latter is the reference material.

[0101] Both prepared cans have been filled with demineralized water and cooled down to 4° C. The open cans have been placed at room temperature and the temperature of the water is followed in time. After 30 minutes, the content of the insulated can showed a temperature of 8° C., while for the reference can a value of 14° C. was recorded. After one hour, the water in the insulated can was still chilly (12° C.), whereas the reference can showed the same temperature as in the room (21° C.).

Example 4

[0102] A standard water-based inside spray lacquer (20% solids) is mixed with 2.0% m/m of a thermally expandable microsphere (initial particle size 15-25 micron, thermal expansion between 125 and 175° C., maximum expansion to 80 micron).

[0103] A bright, washed 33 cl aluminum can is provided with 600 mg inside spray lacquer through a Nordson laboratory inside spray system (double spray gun setup). The can is cured for 3 minutes at 190° C. in a box oven. The can is allowed to cool down to room temperature. Another aluminum can is treated in the same way with standard inside spray lacquer. The latter is the reference material.

[0104] Both prepared cans have been filled with hot water (70° C.). The open cans have been placed at room temperature and the temperature of both the water and the outside of the can is monitored in time. The results are shown in Table 1.

TABLE-US-00001 TABLE 1 Temperature profile of reference can and insulated can upon hot water exposure Temperature Temperature Temperature Temperature Time reference reference insulated insulated (minutes) (° C.) inside (° C.) outside (° C.) inside (° C.) outside 1 67.0 60 68.5 46 3 64.0 57 66.0 44 10 57.0 54 59.0 42 20 51.5 45 53.5 38 30 45.0 40 47.0 34 40 41.0 36 43.0 32

[0105] From the results presented in Table 1 it is clearly demonstrated that the insulated can (according to the invention) is capable of maintaining the temperature of the hot water in the can better compared to the reference can.

[0106] In another test the cans were filled with ice water (4° C.). The open cans have been placed at room temperature and the temperature of the outside of the can is monitored in time. The temperature of the ice water remained 4-5° C., until the ice was fully melted. The results are shown in Table 2.

TABLE-US-00002 TABLE 2 Temperature profile of reference can and insulated can upon ice water exposure Time Temperature reference Temperature insulated (minutes) (° C.) outside (° C.) outside 1 9.5 14.0 5 6.0 13.0 10 7.0 13.0 20 10.0 14.5 30 9.0 14.0

[0107] From the results presented in Table 2 it is clearly demonstrated that the insulated can (according to the invention) is capable of maintaining the temperature of the ice water in the can better compared to the reference can.