WO2000063318A1

WO2000063318A1 - Fluorescent composition

Info

Publication number: WO2000063318A1
Application number: PCT/EP2000/003165
Authority: WO
Inventors: Johannes Leugs; Adrianus Hendrikus Van Rooijen; Volkhard Karl Wiese; Steffi Reinhardt; Volker Steinert; Michael Stephan
Original assignee: Ciba Specialty Chemicals Holding Inc.
Priority date: 1999-04-19
Filing date: 2000-04-10
Publication date: 2000-10-26
Also published as: AU2000243992A1

Abstract

Fluorescent composition consisting essentially of a fluorescent dyestuff and a polymer, wherein the polymer contains carboxylic acid and carboxylate groups, process for its preparation and its use.

Description

Fluorescent Composition

The invention on hand relates to a fluorescent composition consisting essentially of a fluorescent dyestuff and a polymer, wherein the polymer contains carboxylic acid and carboxylate groups.

In contrast to conventional organic pigments, fluorescent pigments are solid state solutions of common fluorescent dyes in polymeric resins or matrices. Usually matrices are used which are formed by melt condensation of melamine, formaldehyde, and toluenesulfon-amide, and polymers based on e.g. polymethyl methacrylate ("PMMA"), or polyamides.

US 5,710,197 describes a process for the manufacture of a fluorescent pigment comprising a polymer matrix based on PMMA and a nonpolar fluorescent dye from the coumarin or perylene series. Although according to US 5,710,197 the migration fastness was improved compared to products disclosed in DE-A 39 33 903, the migration fastness is still not satisfying for some applications. Further, only nonpolar dyes can be used, and the polymer matrix is crosslinked, i.e. a crosslinking monomer has to be added before or during the polymerization step thereby increasing costs and efforts for handling an additional component.

Hence, the object of this invention was to provide further fluorescent pigments with an improved migrations fastness. Especially, the use of a crosslinking monomer should not be necessary, preferably it should be avoided, and it should be possible to use all fluorescent dyes and not only nonpolar dyes. In addition, the migration fastness should not be improved at the expense of other properties such as light fastness, heat stability, or ecological reasons as well.

Accordingly, the above defined composition was found. In addition, a process for its preparation, its use and high molecular organic materials pigmented with the inventive compositions were found.

According to the invention, a polymer containing carboxylic acid and carboxylate groups is used. Such as polymers which are obtainable by the polymerization of CH₂=C(H,Me)-(CH₂)_n- COOH, wherein n is 0, 1, 2, 3, 4 or 5, and optional comonomers, which is treated after the polymerization step with a neutralising agent resulting in a polymer, wherein not all of the carboxylic acid groups are neutralized.

Preferably, an acrylic acid and optional comonomers are used.

In the context of this invention the term "polymer" shall include the term "copolymer" throughout the application.

Usually, the molecular weight of the polymer is chosen in the range of from 60,000 to 600,000, preferred from 75,000 to 500,000 g/mol.

Generally, some, but not all of the carboxylic acid groups of the polymer are transformed into the carboxylate (= salt form) by adding a neutralising agent. This can be expressed in a more quantitative way by counting the number of neutralized carboxylic acid groups and the number of carboxylic groups of carboxylic groups before the neutralization step.

Hence, another preferred embodiment of this invention relates to a polymer containing carboxylic acid groups and carboxylate groups, wherein the degree of neutralization, α, is chosen in the range of preferably from 0.05 to 1.00, more preferably from 0.06 to 0.75, most preferably from 0.06 to 0.50, and whereby the degree of neutralization is defined as mole of carboxylic acid groups of which the proton of the carboxylic group is replaced by a cation from the neutralising agent (cat-AA) divided by the mole of all carboxylic acid groups before the neutralization (which is equivalent to the sum of cat-AA and H-AA, wherein H-AA stands for the number of non-neutralized carboxylic acid groups): α = cat-AA/(cat-AA + H-AA)

As a neutralising agent oxides, hydroxides, carbonates and C₁-C₄alcoholates of alkali or alkaline-earth metals such as sodium oxide, potassium oxide, magnesium oxide, calcium oxide, lithium hydroxide, sodium hydroxide, or potassium hydroxide, magnesium carbonate, calcium carbonate, sodium methylate, sodium ethylate, magnesium hydroxide, or magnesium ethylate, or basic ammonium compounds such as ammonium hydroxide or salts having volatile anions such as carbonates or acetates, preferably ammonium carbonate, can be used. Most preferred are sodium hydroxide, or sodium methylate. Further, it is also possible to use as a neutralising agent amides such as alkali metal amides like NaNH₂,or KNH₂, or organic amines such as primary, secondary, tertiary or quaternary amines, preferably tetramethyl ammonium chloride.

Hence, the cation mentioned above may be a cation of the abovementioned alkali metals, alkaline-earth metals or unsubstituted or substituted ammonium.

In a preferred embodiment of this invention a polymer is used which is obtainable by

(A) polymerizing a mixture consisting essentially of

(a) from 20 to 100, preferably from 25 to 90, more preferred 30 to 80 % by weight of acrylic acid,

(b) from 0 to 50, preferably from 1 to 40, more preferred 5 to 30 % by weight of a copolymerizable, monoethylenically unsaturated monomer, other than (c)

(c) from 0 to 60, preferably from 5 to 55, more preferred 10 to 50 % by weight of a C_rC₈-alkyl ester of acrylic or methacrylic acid, wherein the sum of the components (a) to (c) is 100 % by weight, and

(B) treating the so obtained polymer with a neutralising agent, preferably with a hydroxide of an alkali metal, an alkaline-earth metal or ammonium, an alkali metal or alkaline-earth metal C C₄alcoholate, an amide of an alkali metal, an amine, or a salt of an a alkali metal or alkaline-earth metal cation and a volatile anion, particularly preferred wherein the degree of neutralization α is in the range of from 0.05 to 1.00.

As component (b) methacrylic acid,

esters of methacrylic or acrylic acid, such as 2-hydroxyethyl acrylate, acrylonitrile, methacrylonitrile, 2-hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, dimethylaminoethyl methacrylate, dimethylaminoethyl acrylate, styrene and its derivatives, maleic acid, or maleic acid anhydride, or mixtures thereof, preferably methacrylic acid, may be used.

As component (c) methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, sec-butyl methacrylate, tert.-butyl methacrylate, pentyl methacrylate, hexyl methacrylate, heptyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, isobutyl acrylate, sec-butyl acrylate, tert.-butyl acrylate, pentyl acrylate, hexyl acrylate, heptyl acrylate, octyl acrylate or 2-ethylhexyl acrylate, and mixtures thereof, particularly methyl methacrylate or n-butyl acrylate, particularly preferably n- butyl acrylate or a mixture of methyl methacrylate and n-butyl methacrylate may be used. As fluorescent dyestuff all known fluorescent organic compounds can be used, preferably those which are soluble in the monomer or monomer mixture, most preferably are those which belong to the following families known as benzothioxanthene, benzoxanthene, xanthene, coumarin, naphthalimide, perylene, benz[4,5]imidazo[2,1-a]isoindol-11-one, particularly preferred as host compound in combination with quinacridones, perylenes, perinones, diketopyrrolopyrroles, rhodamines, coumarins, cyanins, phthalocyanines, porphyrins, styryl dyes as guest compounds, maleinimide, and acridine. Typical dyes include Basic Red 1 , Basic Violet 10 (= rhodamine B, e.g. FLEXO RED 540® from BASF), Basic Violet 11 , Basic Violet 16, Basic Yellow 40 (such as MAXILON FLAVINE 10 GFF® from Ciba Specialty Chemicals), Basic Yellow 101, Solvent Yellow 43, Solvent Yellow 44, Solvent Yellow131, and Solvent Yellow 135.

A further embodiment of the invention on hand concerns a fluorescent composition, wherein

(a) the amount of the polymer containing carboxylic acid groups and carboxylate groups is chosen in the range of from 90 to 99.9, preferred from 97 to 99.5 % by weight, based on the fluorescent composition, and

(b) the amount of fluorescent dyestuff is chosen in the range of from 10 to 0J , preferred from 3 to 0.5 % by weight, based on the fluorescent composition.

Another preferred embodiment concerns a fluorescent composition, wherein the polymer containing carboxylic acid groups and carboxylate groups is obtainable by (A) polymerizing a mixture consisting essentially of

(a) from 20 to 100, preferred from 25 to 90, particularly preferred from 30 to 80 % by weight of acrylic acid,

(b) from 0 to 50, preferred from 1 to 40, particularly preferred from 5 to 30 % by weight of a copolymerizable, monoethylenically unsaturated monomer, other than (c), and

(c) from 0 to 60, preferred from 5 to 55, particularly preferred from 10 to 50 % by weight of a ester of acrylic or methacrylic acid, preferably in the presence of a fluorescent dyestuff, wherein the sum of the components (a) to (c) amounts to 100 % by weight, and

(B) treating the so obtained polymer with a neutralising agent, preferably with a hydroxide of an alkali metal, an alkaline-earth metal or ammonium, an alkali metal or alkaline-earth metal C_rC₄alcoholate, an amide of an alkali metal, an amine, or a salt of an a alkali metal or alkaline-earth metal cation and a volatile anion, particularly preferred wherein the degree of neutralization α is in the range of from 0.05 to 1.00.

The preparation of the polymers usually can be carried out by any known method in the art such as mass, suspension, emulsion, inverse emulsion or solution polymerization either batchwise or continuously, preferably a batchwise or continuous mass polymerization is chosen, particularly preferred is a continuous mass polymerization.

E.g. Kunststoff-Handbuch, Band IX, "Polymethacrylate", 1975, S. 15ff etc. describes details concerning the preparation of poly(meth)acrylates. The polymerization of acrylic acid can be carried out according to procedures described in the following literature: solution polymerization e.g. in JP-A 63275607, inverse emulsion polymerization e.g. in US 3,278,506 and US 3,284,393, precipitation polymerization e.g. in DE-A 1 ,595,727 and Makromol. Chem. 175 (1974) 3207. Further information can be found in Ullmann's encyclopedia of chemistry, Vol. A21.

Preferably, initiators are used for the present invention such as commonly used initiators for polymerisations e.g. peroxides, peresters, hydroperoxides and some azo compounds and also mixtures thereof.

Preferred initiators are selected from the group consisting of tert.-butyl peroxyneodecanoate (TBPND), tert.-butylperoxyethylhexylcarbonate (TBPEHC) tert.-amylperoxyneodecanoate (TAPND), tert.-amylperoxypivalate (TAPPI), tert.-butylperoxypivalate (TBPPI), 2,5-dimethyl- 2,5-di(2-ethylhexanoylperoxy)hexane (DHPEH), tert.-amylperoxy-2-ethylhexanoate (TAPEH), tert.-butylperoxy-2-ethylhexanoate (TBPEH), tert.-butylperoxy-3,5,5-trimethylhexanoate (TBPIN) and mixtures thereof. - D -

Particularly preferred are mixtures of tert.-butylperoxyneodecanoate and tert.-butylperoxy- ethylhexylcarbonate, preferably chosen in the range of from 50 to 90% b.w. TBPND and 50 to 10% b.w. TBPEHC, the total sum being 100%, especially preferred is a weight ratio of in the range of from (70 to 80)/(30 to 20) (TBPND/TBPEHC).

The amount of initiator or mixture of initiators usually is chosen in the range of from 0J to 1.0 mol-%, preferably from 0.2 to 0.4 mol-%, based on the total quantity of monomers.

A further embodiment of this invention relates to a process for the preparation of the fluorescent composition comprising treating a mixture of (a) a polymer which contains carboxylic acid groups and (b) a fluorescent dyestuff with a neutralizing agent.

As polymers the abovementioned polymers as a rule are used. In a preferred embodiment the fluorescent dyestuff is incorporated before or during the polymerization step of the used polymer. The treatment with the neutralizing agent usually is carried out in adding a neutralizing agent to the mixture of the polymer containing carboxylic acid groups and the fluorescent dyestuff.

In a further preferred embodiment, the polymer is ground after the polymerization step, but before the neutralization step. Preferably, a particle size smaller than 100 μm is chosen.

The treatment with a neutralizing agent can be carried out in solution or in a melt of the polymer, preferably, the treatment with the neutralizing agent is carried out in a solvent. As solvents inorganic polar solvents such as water, or organic polar solvents such as mentioned in Polymer Handbook, 3rd Edition, J.Brandrup, E.H.Immergut, John Wiley&Sons 1989, Cap. VIII, p. 379 can be used, preferably alkanols having one, two or three hydroxy groups, esters like ethylacetate, ketones such as acetone, cyclic ethers such as dioxane, aromatic hydrocarbons such as benzene, toluene, xylene, formamides such as dimethylformamide or mixtures thereof, more preferably a mixture of water and ethanol is used, preferably in a weight ration in the range of from 5:1 to 0.2:1 , particularly preferred from 2:1 to 0.5:1.

Usually, per 5 to 20 kg of the polymer an amount of 50 to 200 kg of the desired solvent is used. The amount of chosen neutralizing agent depends primarily on the desired degree of neutralization and the chosen neutralizing agent. Therefore, it is preferred to calculate the amount of neutralizing agent if the desired degree of neutralization is defined.

Another preferred embodiment relates to a process for the preparation of the fluorescent composition comprising either

(a) treating a mixture of a polymer based on acrylic acid and a fluorescent dyestuff with a neutralizing agent or

(b) polymerizing a mixture of acrylic acid or a derivative thereof containing a carboxyl group and a salt of acrylic acid or a derivative thereof containing a carboxylate group via inverse emulsion in the presence of a fluorescent dyestuff or

(c) polymerizing a mixture of acrylic acid or a derivative thereof containing a carboxyl group and a salt of acrylic acid or a derivative thereof containing a carboxylate group via inverse emulsion in the absence of a fluorescent dyestuff, and then adding a fluorescent dyestuff to the obtained polymer.

Another preferred embodiment of this invention concerns a process for the preparation of the inventive fluorescent composition, wherein a compound selected from the group consisting of a hydroxide of an alkali metal, an alkaline-earth metal or ammonium, an alkali metal or alkaline-earth metal C₁-C₄alcoholate, an amide of an alkali metal, an amine, or a salt of an a alkali metal or alkaline-earth metal cation and a volatile anion, is chosen as neutralizing agent.

Another preferred embodiment of the present invention relates to a process for the preparation of the inventive fluorescent composition, wherein the polymerization of the monomer or monomers in the presence of the fluorescent dyestuff is carried out in an extruder. Preferably, the neutralization is also carried out either in the same or in an additional extruder, or as described above.

Hence, this inventive process consists of the following steps: (A) introducing continuously into the extruder

(I) from 90 to 99.9, preferred from 97 to 99.5 % by weight, based on the sum of (I) and WO 00/63318 _Q PCT/EPOO/03165

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(II), a mixture consisting essentially of

(a) from 20 to 100, preferably, from 25 to 90, more preferred from 30 to 80 % by weight of acrylic acid,

(b) from 0 to 50, preferably from 1 to 40, more preferred 5 to 30 % by weight of a copolymerizable, monoethylenically unsaturated monomer, other than (c),

(c) from 0 to 60, preferably from 5 to 55, more preferred 10 to 50 % by weight of a C_r C₈-alkyl ester of acrylic or methacrylic acid, wherein the sum of the components (a) to (c) is 100 % by weight, and

(II) from 0J to 10, preferred from 3 to 0.5 % by weight, based on the sum of (I) and (II), of a fluorescent dyestuff, and

(III) optionally from 0J to 1.0 mol-%, based on the amount of monomers (a) to (c), of an initiator,

(B) simultaneously mixing the components (I) to (III), and polymerizing the monomer or copolymerizing the monomer mixture within the extruder by heating,

(C) withdrawing continuously the obtained reaction mixture from the extruder, and

(D) treating the so obtained reaction mixture with a neutralizing agent, preferably with a compound selected from the group consisting of a hydroxide of an alkali metal, an alkaline- earth metal or ammonium, an alkali metal or alkaline-earth metal C₁-C₄alcoholate, an amide of an alkali metal, an amine, or a salt of an a alkali metal or alkaline-earth metal cation and a volatile anion, particularly preferred wherein the degree of neutralization α is in the range of from 0.05 to 1.00.

In a preferred embodiment the treating with a neutralising agent is carried out in a second extruder. And in a further preferred embodiment, the treating with a neutralising agent is carried out in the extruder after step (B), but before step (C).

In another preferred embodiment, the monomers are admixed with the initiator or mixture of initiators before it is introduced into the extruder.

The admixture can be carried out by known methods e.g. by mixing the components in usual vessels and agitators, static mixers etc. If the initiator or mixture of initiators is admixed with the monomers, it is preferred to cool the admixture after it is admixed, especially if it is desired to store it, usually at a temperature in the range of from -30 to 5°C, preferably from -20 to -5°C.

If desired, the usual additives and fillers such as rheology improvers usually in amounts ranging from 0.01 to 15% by weight, related to the total amount of reactants, dispersants usually in amounts in the range of from 0.01 to 30% by weight, related to the total amount of reactants, and stabilizers and antioxidants in effective amounts may be added. As a rule, the reaction temperature usually should be chosen sufficiently high to ensure that the polymerization reaction takes place in a reasonable time. In general, this depends of course from the chosen reactants, but can be figured out easily by a person skilled in the art, because the corresponding data are well-known in the art. As a rule, the reaction can be carried out at from 70 to 220°C, preferably from 90 to 200°C. Especially, in the case where AA, MMA and/or BA are to be polymerized the reaction can be carried out at a temperature in the range of from 100 to 180°C.

Usually, the reaction time depends on the chosen reactants, the desired molecular weight of the polymer to be produced, the chosen reaction temperature, etc. Suitable reaction times can be found easily by a person skilled in the art, if necessary by a few pilot tests. As an example, in case a AA/MMA/BA mixture and Basic Violet 10 as dyestuff are chosen, the reaction time usually is within the range of 0J to 2 hours, if the reaction temperature is within the range of from 50 to 150°C.

Usually, any kind of extruder can be used, e.g. twin-screw extruders or kneading extruders, but co-rotating twin-screw extruders and especially co-rotating, closely intermeshing extruders are preferred.

The general procedure using an extruder is known, and described e.g. in The Canadian Journal of Chemical Engineering, 71 , June 1993 and US 3,637,545.

In a more preferred embodiment a co-rotating twin-screw extruder is used with a UD (length/diameter) ratio in the range of from 30 to 60, particularly from 40 to 60. Usually, the throughputs in the extruder depend on the different reactants and, of course, on the size of - 10 -

the extruder. For example, the throughput is preferably chosen in the range of from 0J to 10, more preferred from 1 to 8 kg/h.

In a preferred embodiment of this invention, a temperature profile is applied to different zones of the used extruder depending on the chosen pigment and monomer. Preferred e.g. is a temperature profile in which

(a) in approximately within the first quarter of the extruder (0 < x < 0.25L) the temperature is chosen at a range from ambient temperature to about two third of the desired highest temperature,

(b) in the second quarter of the extruder (0.25L < x < 0.5L) the temperature usually is increased to 100% of the desired highest temperature,

(c) in the third quarter of the extruder (0.5L < x < 0.75L) the temperature is in the range of 100 to 80% of the desired highest temperature, preferably the temperature is decreased at the end of this part of the extruder to 80 to 90% of the desired highest temperature,

(d) in the last quarter of the extruder (0.75L<x<L) at the beginning of this part of the extruder the temperature preferably is chosen at about 80 to 90% of the desired highest temperature and then, in the following parts of the extruder, is increased to about 100 to 120% of the highest desired temperature chosen in the second part of the extruder (b).

In other preferred embodiments the zone of the extruder with the desired highest temperature (see above part (b)) can be extended, preferably in combination with the overall length L of the extruder, and, of course, more detailed profiles can be chosen, usually depending on the chosen pigments, monomers, initiators, and chain transfer agents.

According to the invention, the reaction mixture is withdrawn continuously from the extruder by known methods, e.g. it is usually released into air and/or water at ambient temperature and atmospheric pressure. If desired, further work-up can be carried out such as granulating or pulverizing by known methods to yield granules, powders or pastes, if the powder is mixed with an organic solvent or water.

The thus obtained reaction mixture can be treated with a neutralizing agent in a solution as described above, or, in another preferred embodiment, in a second extruder. WO 00/63318 _{Λ <} PCT/EPOO/03165

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Hence, if the reaction mixture is treated with a neutralizing agent in a second extruder, usually the reaction mixture (polymer comprising the fluorescent dyestuff), and an aqueous solution of a neutralizing agent having a concentration in the range of from 25 to 70 % by weight are metered into an extruder, preferably a co-rotating twin screw extruder, with a L/D in the range of from 20 to 60, preferably 35 to 45, with throughput ratio in the range of from 1 to 20, preferably from 5 to 10 (throughput of copolymer in kg/h : throughput of aqueous neutralizing agent solution in kg/h). Preferably, the extruder barrel is divided in at least 10 zones, particularly 14 zones, usually all having the same length. As a rule the zones are connected into at least 5 heating zones, particularly 7 heating zones, wherein preferably each heating zone is heated individually.

The temperature profile to be applied depends essentially on the chosen educts and desired ratios and properties. As an example, if a AA/MMA/BA is chosen the following temperature profile on an extruder having 14 zones and 7 heating zones with an IJD = 41 is most preferred:

1 = input zone copolymer, 5 = input zone aqueous neutralizing agent, 14 = die-head: zone 1 2 3 4 5 6 7 8 9 10 11 12 13 14 A B B C C C D D D E E F F G T (°C) 30 200 200 200 200 200 200

Preferably, in this preferred arrangement, the polymer melt is degassed at zone 11 at a pressure of about 200 mbar, then the extrudate is collected in a container and broken.

As a rule, the degree of neutralization can be calculated from the concentration of carboxylic groups of the copolymer before and after neutralization by potentiometric titration with 1 N LiOH in water/acetone as solvent. Another preferred possibility is to use IR-analysis.

In a more preferred embodiment of this invention, the inventive fluorescent compositions exhibit a particle size of below 10 μm, preferably from 1 to 5 μm.

In case the inventive fluorescent compositions do not have a particle size below 10 μm, known methods can be applied to achieve the desired result, such as milling, e.g. in a ball mill, followed by e.g. fractionating by suspension sieving, preferably with a volatile non- solvent such as n-heptane using an ultrasonic disintegrator. Other possibilities such as using jet mills are known in the art.

Another preferred embodiment of this invention relates to an inventive fluorescent composition obtained according to the afore described inventive processes.

Another embodiment of the present invention is related to the use of the inventive fluorescent compositions for the preparation of coloring high molecular weight organic materials (having a molecular weight usually in the range of from 10³ to 10⁷ g/mol), e.g. biopolymers, plastic materials, including fibres, glasses, ceramic products, for formulations in decorative cosmetics, for the preparation of inks, printing inks, paint systems, in particular automotive lacquers, fluorescent whitening agents, photocell aggregates, color filters and dispersion colors and, furthermore, the inventive fluorescent compositions can be used in the biomedical field of application, e.g. for the preparation of diagnostic agents as well as in the fields of impact-printing and non-impact-printing and photo/repro in general.

Illustrative examples of suitable organic materials of high molecular weight which can be colored with the inventive fluorescent compositions of this invention are vinyl polymers, for example polystyrene, poly-α-methylstyrene, poly-p-methylstyrene, poly-p-hydroxystyrene, poly-p-hydroxyphenylstyrene, polymethyl methacrylate and polyacrylamide as well as the corresponding methacrylic compounds, polymethylmaleate, polyacrylonitrile, polymethacrylonitrile, polyvinyl chloride, polyvinyl fluoride, polyvinylidene chloride, polyvinylidene fluoride, polyvinyl acetate, polymethyl vinyl ether and polybutyl vinyl ether; polymers which are derived from maleinimide and/or maleic anhydride, such as copolymers of maleic anhydride with styrene; polyvinyl pyrrolidone; ABS; ASA; polyamides; polyimides; polyamidimides; polysulfones; polyether sulfones; polyphenylene oxides; polyurethanes; polyureas; polycarbonates; polyarylenes; polyarylene sulfides; polyepoxides; polyolefins such as polyethylene and polypropylene; polyalkadienes; biopolymers and the derivatives thereof e.g. cellulose, cellulose ethers and esters such as ethylcellulose, nitrocellulose, cellulose acetate and cellulose butyrate, starch, chitin, chitosan, gelatin, zein; natural resins; synthetic resins such as alkyd resins, acrylic resins, phenolic resins, epoxide resins, aminoformaldehyde resins such as urea/formaldehyde resins and melamine/formaldehyde resin; vulcanized rubber; casein; silicone and silicone resins; rubber, chlorinated rubber; and also polymers which are used, for example, as binders in paint systems, such as novolaks which are derived from C,-C₆-aldehydes such as formaldehyde and acetaldehyde and a binuclear or mononuclear, preferably mononuclear, phenol which, if desired, is substituted by one or two groups, one or two halogen atoms or one phenyl ring, such as o-, m- or p-cresol, xylene, p-tert.-butylphenol, o-, m- or p-nonylphenol, p-chlorophenol or p- phenylphenol, or a compound having more than one phenolic group such as resorcinol, bis(4-hydroxyphenyl)methane or 2,2-bis(4-hydroxyphenyl)propane; as well as suitable mixtures of said materials.

Particularly preferred high molecular weight organic materials, in particular for the preparation of a paint system, a printing ink or ink, are, for example, cellulose ethers and esters, e.g. ethylcellulose, nitrocellulose, cellulose acetate and cellulose butyrate, natural resins or synthetic resins (polymerization or condensation resins) such as aminoplasts, in particular urea/formaldehyde and melamine/formaldehyde resins, alkyd resins, phenolic plastics, polycarbonates, polyolefins, polystyrene, polyvinyl chloride, polyamides, polyurethanes, polyester, ABS, ASA, polyphenylene oxides, vulcanized rubber, casein, silicone and silicone resins as well as their possible mixtures with one another.

It is also possible to use high molecular weight organic materials in dissolved form as film formers, for example boiled linseed oil, nitrocellulose, alkyd resins, phenolic resins, melamine/formaldehyde and urea/formaldehyde resins as well as acrylic resins.

Said high molecular weight organic compounds may be obtained singly or in admixture, for example in the form of granules, plastic materials, melts or in the form of solutions, in particular for the preparation of spinning solutions, paint systems, coating materials, inks or printing inks.

In a particularly preferred embodiment of this invention, the inventive fluorescent compositions are used for the mass coloration of polyvinyl chloride, polyamides and, especially, polyolefins such as polyethylene and polypropylene as well as for the preparation of paint systems, including powder coatings, inks, printing inks, color filters and coating colors. WO 00/63318 _{Λ A} PCT/EPOO/03165

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Illustrative examples of preferred binders for paint systems are alkyd/melamine resin paints, acryl/melamine resin paints, cellulose acetate/cellulose butyrate paints and two-pack system lacquers based on acrylic resins which are crosslinkable with polyisocyanate.

According to observations made to date, the inventive fluorescent compositions can be added in any desired amount to the material to be colored, depending on the end use requirements. In the case of high molecular weight organic materials, for example, the fluorescent compositions prepared according to this invention can be used in an amount in the range from 0.01 to 40, preferably from 0J to 20% by weight, based on the total weight of the colored high molecular weight organic material.

Hence, another embodiment of the present invention relates to a composition comprising of

(a) 0.01 to 40, preferably 0J to 20% by weight, based on the total weight of the colored high molecular organic material, of a fluorescent composition according to the present invention, and

(b) 99.99 to 60, preferably 99.9 to 80% by weight, based on the total weight of the colored high molecular organic material, of a high molecular organic material, and

(c) if desired, customary additives such as rheology improvers, dispersants, fillers, paint auxiliaries, siccatives, plasticizers, UV-stabilizers, and/or additional pigments or corresponding precursors in effective amounts, such as e.g. from 0 to 50% by weight, based on the total weight of (a) and (b).

The pigmenting of the high molecular weight organic materials with the inventive fluorescent compositions usually is effected by incorporating said inventive fluorescent compositions, if desired in the form of masterbatches, in the high molecular weight organic materials using customary apparatus suitable to this end, such as extruders, roll mills, mixing or milling apparatus. The material thus treated is then normally brought into the desired final form by methods which are known per se, such as calandering, moulding, extrusion moulding, coating, casting, extruding, by injection moulding.

To produce non-brittle mouldings or to diminish their brittleness, so-called plasticizers can be added to the high molecular weight substances prior to moulding. Plasticizers may be, for example, esters of phosphoric acid, phthalic acid and sebacic acid. Said plasticizers may be WO 00/63318 _ _{1 5} _ PCT/EPOO/03165

added before, during or after pigmenting the high molecular weight substances with the inventive fluorescent compositions.

To obtain different shades, the inventive fluorescent compositions may advantageously be used in admixture with fillers, transparent and opaque white, colored and/or black pigments as well as customary luster pigments in the desired amount.

For the preparation of paints systems, coating materials, color filters, inks and printing inks, the corresponding high molecular weight organic substances, such as binders, synthetic resin dispersions etc. and the inventive fluorescent compositions are usually dispersed or dissolved together, if desired together with customary additives such as dispersants, fillers, paint auxiliaries, siccatives, plasticizers and/or additional pigments or pigment precursors, in a common solvent or mixture of solvents. This can be achieved by dispersing or dissolving the individual components by themselves, or also several components together, and only then bringing all components together, or by adding everything together at once.

Hence, a further embodiment of the present invention relates to the use of the inventive fluorescent compositions for the preparation of dispersions and the corresponding dispersions, and paint systems, coating materials, color filters, inks and printing inks comprising the inventive fluorescent compositions.

For application in printing, all customary industrial printing processes can be employed, such as screen printing, rotogravure, bronze printing, flexographic printing and offset printing. A still further embodiment concerns a high molecular weight organic material comprising the inventive fluorescent composition.

A particular embodiment of this invention concerns ink jet inks comprising the inventive fluorescent compositions

The desired ink may contain up to 30 % by weight of the fluorescent composition, but will generally be in the range of 0J to 10, preferably from 0J to 8% by weight of the total ink composition for most thermal ink jet printing applications. WO 00/63318 - . PCT/EPOO/03165

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Further, the inks usually contain polymeric dispersants such as random, block, branched or graft polymers or copolymers. Most preferred are polymeric dispersants made by the group transfer polymerization process, because in general these are free from higher molecular weight species that tend to plug pen nozzles.

In AB or BAB block copolymers, the A segment usually is a hydrophobic homopolymer or copolymer which serves to link with the inventive fluorescent composition and the B block generally is a hydrophilic homopolymer or copolymer, or salts thereof and serves to disperse the pigment in the preferably chosen aqueous medium. Such polymeric dispersants and the synthesis thereof are known from e.g. US 5,085,698.

ABC triblocks are also useful as dispersants. In the ABC triblock, the A block usually is a polymer compatible with water, the B block is a polymer capable of binding to the fluorescent composition and the C block is compatible with the organic solvent. Preferably the A and C blocks are end blocks. ABC triblocks and their synthesis are disclosed e.g. in EP-A 556,649. Suitable graft polymers are disclosed in US 5,231 ,131.

Representative compounds useful for this purpose include e.g. polymers of polyvinyl alcohol, cellulosics and ethylene oxide modified polymers, and dispersant compounds containing ionisable groups such as acrylic acid, maleic acid or sulfonic acid.

The polymeric dispersant is generally present in an amount in the range of from 0J to 30, preferably from 0,1 to 8% by weight of the total ink composition.

In addition to, or in place of the preferred polymeric dispersants, surfactants may be used as dispersants. These may be anionic, nonionic, or amphoteric surfactants. A detailed list of non-polymeric as well as some polymeric dispersants is disclosed in the section on dispersants of Manufacturing Confection Publishing Co., (1990) p. 110-129, McCutcheon's Functional Materials, North America Edition.

Usually the ink contains an aqueous medium such as water or a mixture of water and at least one water-soluble organic solvent. Water-soluble organic solvents are well known, representative examples of which are disclosed in e.g. US 5,085,698. Selection of a suitable WO 00/63318 „ _, PCT/EPOO/03165

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mixture of water and water-soluble organic solvent depends on usually requirements of the specific application such as desired surface tension and viscosity, drying time of the ink, and the media substrate onto which the ink will be printed.

Particularly preferred is a mixture of a water-soluble solvent having at least two hydroxyl groups, e.g. diethylene glycol, and water, especially deionized water.

In the event that a mixture of water and a water-soluble organic solvent is used as aqueous medium, water usually would comprise from 30 to 95, preferably 60 to 95% by weight, based on the total weight of the aqueous medium.

The amount of aqueous medium generally is in the range of from 70 to 99.8, preferably from 84 to 99.8%, based on the total weight of the ink.

The ink may contain other ingredients well known to those skilled in the art such as surfactants to alter surface tension as well as to maximize penetration. However, because surfactants may destabilize dispersions, care should be taken to insure compatibility of the surfactant with the other ink components. In general, in aqueous inks, the surfactants may be present in amounts ranging from 0.01 to 5, preferably from 0.2 to 3% by weight, based on the total weight of the ink.

Biocides may be used in the ink compositions to inhibit growth of microorganisms. Sequestering agents such as EDTA may also be included to eliminate deleterious effects of heavy metal impurities. Other known additives, such as viscosity modifiers may also be added.

Especially for ink jet applications, the inventive fluorescent compositions preferably are sufficiently small to permit free flow through an ink jet printing device, particularly at the ejecting nozzles that usually have a diameter of 10 to 50μm. A preferred range of the particle size of the inventive fluorescent compositions is chosen from 0.005 to 10μm, preferably 0.01 to 2, and most preferably from 0.05 to 0.2μm. „ „

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Examples

Spectrophotometrical measurements are carried out on a spectrophotometer SP68 from X- Rite using as software CGREC for windows 1.5. The measurements are performed at calibrated equipment with the observer at 10 degree, D65 as illuminant and gloss included. No special adaptations with respect to measurement of fluorescence have been made.

If not stated otherwise, the hue of the manufactured foils is measured resulting in Cielab values, which are based on the L^'aV-color space (1976) of the Commission Internationale de I'Eclairage (CIE; DIN 5033, part 3; DIN 6174). In this color space L^" indicates lightness and a^" and b^' are the chromaticity coordinates. The hue (or correct: metric hue-angle) is defined by the formula h = tan^"1 (b^"/a^*) [degrees]

The fluorescence is measured spectrophotometrically as that part of the reflection that is more than 100%.

For the determination of the migration a foil is put between two white PVC foils (100 parts SOLVIC 264 (from Solvay), 44 parts dioctyl-phthalate ("DOP"), 2 parts of a stabilizer (STANCLERE 3502) and 0.75 parts TiO₂ (2210, from Kronos) and stored under reduced pressure (< 0J bar) at 80°C for 24 hours. The discoloration of the white foil is measured spectrophotometrically against virgin white PVC foil and is expressed as ΔE according to the formula

ΔE^' _ab = V(Δ ^*)² + (Δa^*)²+(Δb^')²

Comparative example 1 : A mixture of 5.446 g methyl methacrylate (MMA), 5.050 g 2-hydroxy ethyl methacrylate (HEMA), a solution of 0.113 g Basic Violet 10 (FLEXO®RED 540 from BASF) in 0.396 g HEMA, 71.1 mg tert.-butylperoxy neodecanoate (TBPND) and 71.8 mg tert.-butylperoxy ethyl hexyl carbonate (TBPEHC) is homogenized by ultrasonic bath for about 10 minutes. The homogenized mixture is then transferred into a heatable steel autoclave with a working volume of 200 ml. After closing the autoclave it is flushed with nitrogen 3 times. The mass polymerization is performed for 3 hours at 80^βC under a nitrogen pressure of 500 kPa (5 bar). Thereafter the mixture is transferred into an oven where it is _Λ

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heated for 3 hours at 120°C. After the polymerization the product is ground in a ball mill for 90 minutes and is fractionated by suspension sieving with n-heptane using an ultrasonic disintegrator to particles smaller than 71 μm.

250 mg of the obtained fluorescent pigment are mixed with 5.0 g of pulverized polyvinylchloride ("PVC", 100 parts SOLVIC 264 (from Solvay), 44 parts dioctyl-phthalate ("DOP"), 2 parts of a stabilizer (STANCLERE 3502) in a mortar. Then 45.0 g of the same PVC is molten on a two roll mill at 170°C and the PVC/fluorescent pigment mixture is incorporated into the PVC-melt for 5 minutes. The PVC-melt is taken from the two roll mill and about 20 g is pressed into a transparent foil at 190°C. From the remaining part of the PVC- melt about 20 g is put on the two roll mill again (at 170^βC) and 400 mg of a TiO₂ /PVC- masterbatch (MICRANYL®White 40 BG from Ciba Specialty Chemicals) is added (white reduction 1:4). The PVC-melt is processed for 3 minutes. The PVC-melt is taken from the two roll mill and about 20 g are pressed into an opaque foil at 190°C in a mould between two plates of a hydraulic press.

Example 1 : A test tube is charged with 4.356 g MMA, 5.839 g acrylic acid (AA), a solution of 0.11 g FLEXO®RED 540 in 0.44 g AA, 47.9 mg TBPND and 48.3 mg TBPEHC. The polymerization procedure is carried out according to comp. example 1. After the polymerization the product is ground. Then 9.257 g of the product is dissolved in 100 g of a water/ethanol mixture (1:1 w/w-%). Afterwards 1.816 g of a solution of sodium methylate in methanol (30% by weight) are added. For isolating the product, the solvent is removed in a rotary evaporator and the product is dried to constant weight. The product is ground in a ball mill and is fractionated to particles smaller than 5 micron by suspension sieving with n- heptane using an ultrasonic disintegrator. The product is filtered and dried to constant weight.

A transparent foil and an opaque foil are made of the fluorescent pigment according to the procedure described in comp. example 1.

Example 2: Example 1 is repeated, except that the test tube is charged with 3.267 g MMA, 0.545 g butyl acrylate (BA), 6.384 g AA, a solution of 0.110 g FLEXO®RED 540 in 0.440 g AA, 48.3 mg TBPND and 48.7 mg TBPEHC, and that the neutralization is carried out with the following amounts: 10.012 g of the product is dissolved in about 100 g of a water/ethanol - 20 -

mixture (1 :1 w/w-%), and thereafter 1.964 g of a solution of sodium methylate in methanol (30% by weight) are added.

Example 3: Example 1 is repeated, except that the test tube is charged with 3.267 g MMA, 1.089 g BA, 5.712 g AA, a solution of 0.110 g FLEXO®RED 540 in 0.440 g AA, 46.4 mg TBPND and 46.8 mg TBPEHC, and that the neutralization is carried out with the following amounts: 8.886 g of the product are dissolved in about 100 g of a water/ethanol mixture (1:1 w/w-%), and 2.643 g of a solution of sodium methylate in methanol (30 % b.w.) are added.

Example 4: Example 1 is repeated, except that the test tube is charged with 2J78 g MMA, 1.634 g BA, 6.129 g AA, a solution of 0.110 g FLEXO®RED 540 in 0.440 g AA, 46J mg TBPND and 46.5 mg TBPEHC, and that the neutralization is carried out with the following amounts: 8.432 g of the product are dissolved in about 100 g of a water/ethanol mixture (1:1 w/w-%), and 3.388 g of a solution of sodium methylate in methanol (30 % b.w.) are added.

Example 5: Example 1 is repeated, except that the test tube is charged with 2J78 g MMA, 0.545 g BA, 7.644 g AA, a solution of 0.110 g FLEXO®RED 540 in 0.440 g AA, 50.7 mg TBPND and 51.1 mg TBPEHC, and that the neutralization is carried out with the following amounts: 9.577 g of the product are dissolved in about 100 g of a water/ethanol mixture (1:1 w/w-%), and 0.5206 g lithium hydroxide monohydrate (LiOH H₂O) solubilised in 30 g water are added.

Example 6: Example 1 is repeated, except that the test tube is charged with 3.267 g MMA, 0.545 g BA, 6.565 g AA, a solution of 0.110 g FLEXO®RED 540 in 0.440 g AA, 49.2 mg TBPND and 49.6 mg TBPEHC, and that the neutralization is carried out with the following amounts: 10.431 g of the product are dissolved in about 100 g of a water/ethanol mixture (1:1 w/w-%), and 0.361 g magnesium ethylate suspended in 30 g methanol are added.

Comparative example 2: A test tube is charged with 5.446 g methyl methacrylate (MMA), 5.050 g 2-hydroxy ethyl methacrylate (HEMA), a solution of 0.113 g MAXILON®Yellow 10GFF (Ciba Specialty Chemicals) in 0.396 g HEMA, 71.1 mg tert.-butylperoxy neodecanoate (TBPND) and 71.8 mg tert.-butylperoxy ethyl hexyl carbonate (TBPEHC). The mixture is homogenized by ultrasonic for about 10 minutes. Mass polymerization is carried out in a steel autoclave with a working volume of 200 ml. After closing the autoclave it is flushed with nitrogen three times. The reaction is performed for three hours at 80°C under pressure (500 kPa = 5 bar) and subsequently for three hours at 120°C in an oven. After the polymerization the product is ground in a ball mill and is fractionated to particles smaller than 71 micron.

The following table contains the compositions of the inventive fluorescent compositions according to the examples 1-9 and the two comp. examples as well as the degree of neutralization, α, wherein MMA, BA etc. means the corresponding MMA-, BA-units etc. within the polymer :

Table 1

Example Dye MMA BA AA Na-AA α no. (% b.w.) (%bw) (%bw) (%bw) (%bw)

comp.ex 1 1 % FLEXO®RED 540 50 - - 50 HEMA -

1 1% FLEXO®RED 540 40 - 50 10 0J33

2 1% FLEXO®RED 540 30 5 55 10 0J22

3 1% FLEXO®RED 540 30 10 45 15 0.203

4 1% FLEXO®RED 540 20 15 45 20 0.254

5 1% FLEXO®RED 540 20 5 65 10 Li-AA 0J24

6 1% FLEXO®RED 540 30 5 60 5 Mg-AA 0.067 comp.ex.2 1% MAXILON®FLAVINE 50 . . 50 HEMA _

10GFF

Table 2: Results of tests of examples 1-7 and comp. ex. 1-3:

Example L^* a b^* ΔE reflection (%)

comp.exJ 82.9 38.6 - 6.3 12.0 115

1 80.6 34.7 -11.8 1.2 102

2 80J 34.8 -11.8 1.9 100

3 80.5 35.8 -11.5 1.6 103

4 80.2 36.0 -11.7 1.8 102

5 79.3 34.7 -13.5 0.8 104

6 80.2 34.6 -11.7 1.6 104 comp.ex.2 96.3 -14.9 30.7 8.2 103 comp.ex.3 84.2 38.9 - 8.0 12.7 119

As comp. ex. 362.5 mg CORONA®MAGENTA S21 (containing 4% Basic Violet 10, from DayGlo Corp.) is used for the preparation of a transparent foil and an opaque foil according to the procedure described in comp. example 1.

Example 7: A dosing vessel is charged with 1.142 kg MMA, 0.857 kg BA, a solution of 0.055 kg FLEXO®RED 540 in 3.446 kg AA and 0J08 kg butanethiol (BuSH). The mixture is stirred for about 10 minutes. A second dosing vessel is charged with 2 kg of a peroxide mixture of TBPND and TBPEHC in a weight ratio of 70:30. The monomer mixture and the initiator mixture are metered into a co-rotating twin screw extruder with IJD = 52 with throughputs of 1.80 kg/h (monomer mixture) and 0J43 kg/h (initiator mixture) respectively. The extruder barrel is divided into 13 zones, all having the same length. Zones 14 and 15 of the extruder consist of a transition flange and a die-head. Each zone is heated individually. The following temperature profile is applied (1 = input zone monomer mixture, 2 = input zone initiator mixture, 15 = die-head):

zone 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 T (°C) 30 30 30 80 90 110 130 150 160 160 180 160 160 160 180 -.

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The polymer melt is degassed at zone 12 at a pressure of about 5 kPa (50 mbar). The extrudate is collected in a container and broken.

Example 8: The copolymer of example 7 and an aqueous solution of NaOH (50% by weight) are metered into a co-rotating twin screw extruder with L D = 41 with throughputs of 3.50 kg/h (copolymer) and 0.45 kg/h (aqueous NaOH), respectively. The extruder barrel is divided into 14 zones, all having the same length. The zones are connected into 7 heating zones, each heating zone is heated individually. The following temperature profile is applied (1 = input zone copolymer, 5 = input zone aqueous NaOH, 14 = die-head):

zone 1 2 3 4 5 6 7 8 9 10 11 12 13 14 A B B C C C D D D E E F F G T (°C) 30 200 200 200 200 200 200

The polymer melt is degassed at zone 11 at a pressure of about 20 kPa (200 mbar). The extrudate is collected in a container and broken.

The degree of neutralization is calculated from the concentration of carboxylic groups of the copolymer before and after neutralization by potentiometric titration with 1 N LiOH in water/acetone as solvent.

Table 3: Composition of fluorescent pigments of example 8

Example Dye MMA BA AA Na-AA _α

(%bw) (%bw) (%bw) (%bw)

11 1% FLEXO®RED 540 >20 >15 39 19 0.27

wherein MMA etc. means MMA-units etc. in the polymer chain (this composition does not correspond to the starting composition of example 7 due to loss of AA because of its conversion into Na-AA). Table 4: Results of tests of example 8

Example L^' a^* b^' ΔE reflection (%)

16 85.3 34.0 -4.5 8J 114

Claims

1. Fluorescent composition consisting essentially of a fluorescent dyestuff and a polymer, wherein the polymer contains carboxylic acid and carboxylate groups.

2. Fluorescent composition according to claim 1, wherein

(a) the amount of the polymer is chosen in the range of from 90 to 99.9 % by weight, based on the fluorescent composition, and

(b) the amount of fluorescent dyestuff is chosen in the range of from 10 to 0J % by weight, based on the fluorescent composition.

3. Fluorescent composition according to claim 1 or 2, wherein the polymer is obtained by polymerizing a mixture consisting essentially of

(a) from 20 to 100 % by weight of acrylic acid,

(b) from 0 to 50 % by weight of a copolymerizable, monoethylenically unsaturated monomer, and

(c) from 0 to 60 % by weight of methyl methacrylate, wherein the sum of the components (a) to (c) amounts to 100 % by weight, preferably in the presence of the fluorescent dyestuff.

4. Process for the preparation of the fluorescent composition according to claims 1 or 3 comprising either

(c) polymerizing a mixture of acrylic acid or a derivative thereof containing a carboxyl group and a salt of acrylic acid or a derivative thereof containing a carboxylate group via inverse emulsion in the absence of a fluorescent dyestuff, and then adding a fluorescent dyestuff to the obtained polymer. WO 00/63318 __ PCT/EPOO/03165

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5. Process for the preparation of the fluorescent composition according to claims 1 or 3 comprising

(a) polymerizing acrylic acid in the presence of a fluorescent dyestuff, and, optionally, at least one co-monomer, and

(b) treating the obtained mixture with a neutralizing agent.

6. Process for the preparation of the fluorescent composition according to claim 4 or 5, wherein a compound selected from the group consisting of a hydroxide of an alkali metal, an alkaline-earth metal or ammonium, an alkali metal or alkaline-earth metal C₁-C₄alcoholate, an amide of an alkali metal, an amine, or a salt of an a alkali metal or alkaline-earth metal cation and a volatile anion, is chosen as neutralizing agent.

7. Fluorescent composition according to claim 1 obtained according to a process according to any of the claims 4 to 6.

8. Use of the fluorescent composition according to claims 1 to 2 or prepared according to any of the claims 4 to 6 for the preparation of coloring high molecular weight organic materials, for formulations in decorative cosmetics, for the preparation of inks, printing inks, paint systems, in particular automotive lacquers and photoresists, photo- and electroconductive polymers, fluorescent whitening agents, photocell aggregates, colored photoresists, color filters and dispersion colors.

9. High molecular weight organic material comprising the fluorescent composition according to claims 1 to 3 or prepared according to claims 4 to 6.