Novel tint bases and a method of preparing tint bases

Abstract

According to an example aspect of the present invention, there is provided a tint base comprising titanium dioxide, a vehicle, and conventional additives, which tint base is capable of displaying a preselected colour upon the addition of a colorant, wherein at least 4% by weight of the titanium dioxide is present in the form of opaque aggregates of titanium dioxide and precipitated calcium carbonate particles wherein the titanium dioxide particles are at least partially encased by the particles of precipitated calcium carbonate.

Claims

1. A method for reducing an amount of titanium dioxide in a tint base, the method comprising: i) dispersing titanium dioxide particles and opaque aggregates that act as a substitute for titanium dioxide particles in a vehicle to form an intermediate tint base, the opaque aggregates comprising titanium dioxide particles at least partially encased by precipitated calcium carbonate particles; and ii) after step (i), adding back an additional amount of titanium dioxide particles to the intermediate tint base to form a final tint base.

2. The method of claim 1, wherein: in step (i), there is provided a difference between the tint strength of the intermediate tint base and a control tint base formed from the titanium dioxide particles without the opaque aggregates, wherein the control tint base comprises an amount of titanium dioxide particles equal to the sum of the titanium dioxide particles and the opaque aggregates in the intermediate tint base, and in step (ii), due to the adding back of the additional amount of titanium dioxide particles, there is provided a difference between a tint strength of the final tint base and the tint strength of the control tint base that is less than the difference in tint strength between the intermediate tint base and the control tint base.

3. The method of claim 2, wherein, in step (ii), the difference between the tint strength of the final tint base and the control tint base is +/−0.15.

4. The method of claim 2, wherein, in step (i), the difference between a contrast ratio of the intermediate tint base and a contrast ratio of the control tint base is +/−0.20 units.

5. The method of claim 2, wherein, in step (ii), the difference between the tint strength of the intermediate tint base and the tint strength of the control tint base is reduced by from 20-60% in the final tint base.

6. The method of claim 2, wherein a difference between a contrast ratio of the final tint base and a contrast ratio of the control tint base is +/−0.3.

7. The method of claim 2, wherein a ΔE value between the final tint base and the control tint base is +/−0.7.

8. The method of claim 1, wherein the final tint base comprises at least 4 wt % of the opaque aggregates comprising titanium dioxide particles at least partially encased by precipitated calcium carbonate particles.

9. The method of claim 8, wherein the final tint base comprises from 5-50 wt % of the opaque aggregates comprising titanium dioxide particles at least partially encased by precipitated calcium carbonate particles.

10. The method of claim 1, further comprising adding a colorant to the final tint base to form a paint.

11. The method of claim 10, wherein the colorant is present in an amount of from 0.1 to 10% by weight of the total amount of solids in the paint.

12. The method of claim 10, wherein the paint comprises a member from the group consisting of matt paints, flat matt paints, satin or silk paints, eggshell paints, or semi-gloss paints.

13. The method of claim 10, wherein the paint has a gloss value measured at 60° from the vertical using a glossmeter of about 0-10 gloss units and/or a gloss value measured at 85° from the vertical using a glossmeter of about 0-15 gloss units.

14. The method of claim 10, wherein the paint has a gloss value measured at 60° from the vertical using a glossmeter of about 2-15 gloss units and/or a gloss value measured at 85° from the vertical using a glossmeter of about 5-25 gloss units.

15. The method of claim 10, wherein the paint has a gloss value measured at 60° from the vertical using a glossmeter of about 5-25 gloss units and/or a gloss value measured at 85° from the vertical using a glossmeter of about 10-40 gloss units.

16. The method of claim 10, wherein the paint has a gloss value measured at 60° from the vertical using a glossmeter of about 25-75 gloss units and/or a gloss value measured at 20° from the vertical using a glossmeter of about 5-45 gloss units.

17. The method of claim 10, wherein the paint has a gloss value measured at 60° from the vertical using a glossmeter of about 70-95 gloss units and/or a gloss value measured at 20° from the vertical using a glossmeter of about 20-90 gloss units.

Description

EXAMPLES

[0066] Titanium dioxide comprising at least 4% by weight of aggregates of titanium dioxide particles and precipitated calcium carbonate particles wherein the titanium dioxide particles are at least partially encased by the particles of precipitated calcium carbonate are mixed with a vehicle and conventional additives to provide an intermediate tint base having a contrast ratio of +/−0.20 units compared to the corresponding conventional or standard tint base. To the intermediate tint base is added blue or black tinter to find the relative tint strength compared to the original base. Titanium dioxide is then added back (approximately 1-4 percentage points of titanium dioxide missing from conventional or standard tint base) to the intermediate tint base until the tint strength or brightness is essentially the same as the conventional tint base (+/−0.15 ΔL), providing a new tint base. On adding back titanium dioxide, the additives are adjusted to maintain the particle volume concentration (pvc).

[0067] New tint bases provided in this way can be exchanged for the corresponding conventional base without the need to adjust the colour recipe database in the POS software. A speed match library can be made to confirm the accuracy of the colours produced by the conventional base and the new base.

[0068] The colour recipes produced by the speed match will, in most cases, be the same as the original colour recipes. In one embodiment, this is confirmed with visual checks of selected colours. If necessary, where minor differences are calculated, the new recipe library can be easily uploaded to the POS software.

[0069] The method thus provides a reduction of titanium dioxide in a paint. Following a ladder protocol to find the optimum titanium dioxide level, the titanium dioxide level of the reformulated bases is adjusted by adding additional amounts of titanium dioxide until the tint strength of the corresponding original tint base is matched.

[0070] The results of tests on a colour matching protocol are shown in Table 1. Table 2 show modification of the new tint base to match tint strength

TABLE-US-00001 TABLE 1 Standard 15% Replacement 20% Replacement % % % Water Water 28.42 28.18 28.12 Cellulosic Thickener Cellosize QP4400H 0.45 0.45 0.45 Base (pH control) Ammonia (28%) 0.17 0.17 0.17 Dispersant Dispex A40 0.21 0.21 0.21 Coalescening Agent Texanol 0.81 0.80 0.80 Antifoam Foamaster NXZ 0.15 0.15 0.15 Biocide Acticide BX-H 0.06 0.06 0.06 Chalk Queensfil 25 14.25 14.13 14.10 Calcined Clay Polestar 200P 14.25 14.13 14.10 Opacifying Pigment FP-Pigment 0.00 2.17 2.87 Titanium Dioxide TIOXIDE ® TR92 14.54 12.28 11.51 Water Water 12.25 12.73 12.88 Antifoam Foamaster NXZ 0.00 0.00 0.00 VAVeoVa Binder Mowilith LDM 2383 14.45 14.55 14.58 Total 100.00 100.00 100.00 Vol. Solids 31.90 31.90 31.90 TiO2vc 17.00 14.70 14.00 Evc 51.00 53.30 54.00 pvc 68.00 68.00 68.00 Contrast Ratio Std −0.12 −0.15 Tint Strength—Blue L* Std −0.30 −0.47 Tint Strength—Blue ΔE Std 0.47 0.68

[0071] Table 1 shows a standard ladder protocol followed to identify optimum titanium dioxide replacement level with opaque aggregates of titanium dioxide particles at least partially encased in particles of precipitated calcium carbonate (FP-Pigment). As can be seen from the table, the conventional base comprises 14.54 weight % of titanium dioxide. Reducing the weight percentage of titanium dioxide to 12.28 weight % adding 2.17% of the FP-pigment results in a change of contrast ratio ΔCR of −0.12 (15% replacement). Reducing the weight percentage of titanium dioxide to 11.51 and adding 2.87 weight % of FP-pigment results in a change of contrast ratio ΔCR of −0.15 (20% replacement. The tint strength or brightness—Blue L* is −0.30 and −0.47, respectively. ΔE is 0.47 and 0.68, well within industrial quality control test specification.

TABLE-US-00002 TABLE 2 Standard 15% Replacement 15% FP-460/13% TiO2 20% Replacement 20% FP-460/17% TiO2 % % % % % Water Water 28.42 28.18 28.57 28.12 28.61 Cellulosic Thickener Cellosize QP4400H 0.45 0.45 0.45 0.45 0.45 Base (pH control) Ammonia (28%) 0.17 0.17 0.10 0.17 0.10 Dispersant Dispex A40 0.21 0.21 0.21 0.21 0.21 Coalescening Agent Texanol 0.81 0.80 0.82 0.80 0.82 Antifoam Foamaster NXZ 0.15 0.15 0.15 0.15 0.15 Biocide Acticide BX-H 0.06 0.06 0.06 0.06 0.06 Chalk Queensfil 25 14.25 14.13 13.95 14.10 13.83 Calcined Clay Polestar 200P 14.25 14.13 13.95 14.10 13.83 Opacifying Pigment FP-Pigment 2.17 2.19 2.87 2.93 Titanium Dioxide TIOXIDE ® TR92 14.54 12.28 12.71 11.51 12.15 Water Water 12.25 12.73 12.31 12.88 12.32 Antifoam Foamaster NXZ 0.00 0.00 0.00 0.00 0.00 VAVeoVa Binder Mowilith LDM 2383 14.45 14.55 14.52 14.58 14.54 Total 100.00 100.00 100.00 100.00 100.00 Vol. Solids 31.90 31.90 31.90 31.90 31.90 TiO2vc 17.00 14.70 15.30 14.00 14.80 Evc 51.00 53.30 52.70 54.00 53.20 pvc 68.00 68.00 68.00 68.00 68.00 Contrast Ratio Std −0.12 0.02 −0.15 −0.04 Tint Strength - Blue L* Std −0.30 −0.17 −0.47 −0.20 Tint Strength - Blue ΔE Std 0.47 0.37 0.68 0.42

[0072] Table 2 show the formulations described in Table 1 into which small amounts of titanium dioxide have been added back to compensate for the reduction in tint strength. As can be seen, by adding back small amounts of titanium dioxide the change in contrast ratio and the change in tint strength have been reduced considerably in both tint bases.

[0073] The three tint bases, standard, 15% FP pigment/13% titanium dioxide, and 20% FP pigment/17% titanium dioxide were then calibrated in a matching Chromaflo database. This was done by making drawdowns of various quantities of black colorant in each base and measuring these values in the database. In this way the coloristic link between the three bases and the standard Chromaflow base were established.

[0074] After a perfect calibration, file matches (speed matches) of the NCS Fandeck were created in all 3 bases. The colorant system used was Monicolour C.

[0075] Colour formulations which have a maximum addition of 5% of colorants in a 1 litre formulation were focussed on.

[0076] This resulted in 3 sets of colour formulations (1 set for each base). In most cases the formulations of the 15/13 and 20/17 base were the same as the formulation of the STD base. Any differences found were very small and within the normal tolerances of a tinting system.

[0077] 52 colours were selected covering the whole colour area. These colours were made in the 3 bases in real paint using the speed file matches. This was to enable a visual check of the accuracy of the colours of the 15/13 and 20/17 base compared to the standard base. The result is that all 52 colours are visually perfect matches in both bases compared to the standard.

[0078] Out of the 52 colours the 14 most difficult colours to match were selected. Difficult in this case means those colours where the human eye immediately sees the difference if the colour is not the same. The 52 colours are shown in Table 3. The 14 most difficult to colour match of those colours are shown in Table 4.

TABLE-US-00003 TABLE 3 Colour Matched Colours NCS S 0510-B NCS S 0510-R NCS S 0510-Y NCS S 0510-G NCS S 0520-G50Y NCS S 1030-R10B NCS S 1030-Y30R NCS S 3010-B30G NCS S 3010-G30Y NCS S 3010-R30B NCS S 3010-Y30R NCS S 1000-N NCS S 2000-N NCS S 3000-N NCS S 0520-B50G NCS S 0520-R70B NCS S 0520-Y50R NCS S 0530-B50G NCS S 0530-G40Y NCS S 0530-R80B NCS S 0530-Y40R NCS S 0540-B30G NCS S 0540-G20Y NCS S 0540-R20B NCS S 0540-Y30R NCS S 1010-B90G NCS S 1010-G40Y NCS S 1010-R90B NCS S 1010-Y70R NCS S 1020-B30G NCS S 1020-G50Y NCS S 1020-R40B NCS S 1020-Y30R NCS S 1030-B10G NCS S 1030-B10G NCS S 1030-G10Y NCS S 1040-R NCS S 1040-B10G NCS S 1040-G NCS S 1040-Y40R NCS S 2010-B70G NCS S 2010-G70Y NCS S 2010-R70B NCS S 2010-Y70R NCS S 2020-B50G NCS S 2020-G50Y NCS S 2020-R50B NCS S 2020-Y50R NCS S 3020-B NCS S 3020-G NCS S 3020-R NCS S 3020-Y

TABLE-US-00004 TABLE 4 Difficult to Colour Match Colours NCS S 0510-B NCS S 0510-R NCS S 0510-Y NCS S 0510-G NCS S 0520-G50Y NCS S 1030-R10B NCS S 1030-Y30R NCS S 3010-B30G NCS S 3010-G30Y NCS S 3010-R30B NCS S 3010-Y30R NCS S 1000-N NCS S 2000-N NCS S 3000-N

[0079] Those 14 colours were made again in the 15/13 and 20/17 base in real paint. However this time using only the file match of the STD base. Meaning no possible adjustments in the file match compared to the standard. This is the case when a customer is changing the base using FP-pigment but is not making any changes in the colour formulations in the POS software.

[0080] This resulted also in 14 visually perfect matches in both bases compared to the standard.

[0081] Thus, by adjusting the colour strength of the bases that use FP-pigment to the colour strength of the original base not using FP-pigment, there is no need to change the colour formulations in the POS system.

[0082] It is to be understood that the embodiments of the invention disclosed are not limited to the particular structures, process steps, or materials disclosed herein, but are extended to equivalents thereof as would be recognized by those ordinarily skilled in the relevant arts. It should also be understood that terminology employed herein is used for the purpose of describing particular embodiments only and is not intended to be limiting.

[0083] Reference throughout this specification to one embodiment or an embodiment means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment. Where reference is made to a numerical value using a term such as, for example, about or substantially, the exact numerical value is also disclosed.

[0084] As used herein, a plurality of items, structural elements, compositional elements, and/or materials may be presented in a common list for convenience. However, these lists should be construed as though each member of the list is individually identified as a separate and unique member. Thus, no individual member of such list should be construed as a de facto equivalent of any other member of the same list solely based on their presentation in a common group without indications to the contrary. In addition, various embodiments and example of the present invention may be referred to herein along with alternatives for the various components thereof. It is understood that such embodiments, examples, and alternatives are not to be construed as de facto equivalents of one another, but are to be considered as separate and autonomous representations of the present invention.

[0085] Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided, such as examples of lengths, widths, shapes, etc., to provide a thorough understanding of embodiments of the invention. One skilled in the relevant art will recognize, however, that the invention can be practiced without one or more of the specific details, or with other methods, components, materials, etc. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention.

[0086] While the forgoing examples are illustrative of the principles of the present invention in one or more particular applications, it will be apparent to those of ordinary skill in the art that numerous modifications in form, usage and details of implementation can be made without the exercise of inventive faculty, and without departing from the principles and concepts of the invention. Accordingly, it is not intended that the invention be limited, except as by the claims set forth below.

[0087] The verbs “to comprise” and “to include” are used in this document as open limitations that neither exclude nor require the existence of also un-recited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated. Furthermore, it is to be understood that the use of “a” or “an”, that is, a singular form, throughout this document does not exclude a plurality.

INDUSTRIAL APPLICABILITY

[0088] At least some embodiments of the present invention find industrial application in production of tint bases and paint compositions, as well as in the production of coatings and in the preparation of coatings using such compositions. As will appear from the above, the present tint bases can be provided both as consumer products to be formulated at a hardware store or paint shop as well as an intermediate composition to be used at a paint factory for formulating the final paint composition. In both cases, and in particular in the case of consumer products, the tint base is for example supplied in a closed container, typically a metal or plastic container. In particular tint bases of the present kind are supplied in metal containers, which preferably have a lid which hermetically closes the container. The volume of the container can vary broadly, from about 0.1 to 2501, in particular about 0.3 to 1001, such as 0.3 to 101. As mentioned above, the container is typically underfilled with 5 to 20%, for example about 10%, with the tint based.