Fluorescent whitening agents

Abstract

The invention provides a fluorescent whitening agent or optical brightener of formula (I) or (II) having the structure: (I) (II), wherein Y is Z or X'L; wherein: A is CR1R2(CH2)n wherein R1 is H, CH2OH or COZ, R2 is H or CH2OH and wherein n is 1 or 2, or wherein A is an optionally substituted aromatic or heteroaromatic ring fused with N and X wherein N and X are respectively bound to adjacent carbon atoms on the ring; X is 0, S or N-H; Y is Z or X'L; the or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR4 2, wherein M is selected from an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl alcohol polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester having from 2 to 1000 repeat units, or a polyoxyalkylene chain having from 2 to 1000 repeating units; q is 1 to 5; R4 is independently selected from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; alternatively, NR4 2 represents a heterocyclic ring, e.g. morpholine; and wherein when Y is X'L; X' is 0, S or N-H; and L represents a linker moiety connecting m repeating units of formula I or II having X' as defined above in place of Y; R is H, CHR5R6, R5, R6, an alkylsulphonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) in which each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl, or cyano, optionally wherein R5 and R6 are the same or different, and n is 1 or 2.

Description

1 / 67 “FLUORESCENT BLEACHING AGENTS” Field of Invention

[001] The present invention relates to fluorescent brightening agents (FWAs), optical brighteners and certain applications. Description of the State of the Art

[002] Standard industrial FWAs in the powdered soap industry include CAS 16090-02-1 (DAS-1), CAS 16470-24-9 (DAS-2), CAS 27344-41-8 (DSBP), and CAS 4404-43-7 (FB28). These and other conventional FWAs or optical brighteners suffer from one or more of the following disadvantages: 1. They are conventionally manufactured from fossil fuels; 2. They are not biodegradable; 3. They are toxic in aquatic environments.

[003] The present invention aims to provide enhanced FWAs or optical brighteners in at least one of these aspects.

[004] There is state-of-the-art recognition that fluorophores can be synthesized from sustainable materials, such as citric acid.

[005] In this regard, RSC Adv., 2015, 5, 34795, discloses 4-oxo-1thia-3a-aza-6-indancarboxylic acid and 5-oxo-2,3-dihydro-5H-[1,3]oxazolo[3,2a]pyridine-7-carboxylic acid obtained by condensation of citric acid with amino acids or their derivatives, but without suggesting any potential application. The first compound mentioned is also disclosed in CN108101929 and CN104530089 in the context of fluorescent imaging agents for medical use. The second compound mentioned is described in Wiktor Kasprzyk et al., Luminescence phenomena of biodegradable photoluminescent poly(diol citrate), Chem. Comm., 2013, 49, 57, 6445, and associated supplementary information, 1-21, which describe the luminescent properties of biodegradable photoluminescent polyesters, such as 5-oxo-2,3-dihydro-5H-[1,3]thiazolo[3,2-a]pyridine-3,7-dicarboxylic acid (TPA), as determined by a series of analytical methods. Petition 870250079624, dated 05 / 09 / 2025, pages 638 / 725 2 / 67

[006] J. Mater. Chem. C, 2015,3, 5976-5984 discloses 1,2,3,5-tetrahydro-5oxo-imidazo[1,2-a]pyridine-7-carboxylic acid) and methyl 4-oxo-1-thia-3a-aza-6indancarboxylate in connection with the fabrication of fluorescent carbon nanoparticles from the pyrolysis of citric acid and amine. The first of these compounds is also disclosed for use as a pharmaceutical intermediate in CN114507230.

[007] Methyl-4-oxo-1-thia-3a-aza-3,6-indancarboxylic acid is disclosed, also in connection with fluorescent carbon nanoparticles, in RSC Adv., 2022, 12, 19, 11640-11648 (Table 1 AB).

[008] CN109438479 discloses hexyl 4-oxo-1-thia-3a-aza-6-indancarboxylate and some other indancarboxylate compounds in connection with potential application in fluorescent brightening, although the specific field of application is not specified. In particular, CN109438479 describes an ultraviolet absorber, which has a pyridinone ester backbone structure, to which flexible alkyl chains and water-soluble groups are added to alter the water solubility and dispersibility within polymers, so that the range of application of the ultraviolet absorber can be expanded. Furthermore, the ultraviolet absorber is provided with a plurality of controllable sites to alter the optical properties largely to meet different requirements.

[009] CN110330496 describes an ultraviolet light-absorbing material, as well as a method of preparation and its application. The material has ultraviolet light absorption of pyridine ketonic acid radicals and salt resolvability, solves the problem that a pyridine ketonic acid type ultraviolet light-absorbing material is poor in water solubility and can be widely applied to ultraviolet light-absorbing industries.

[0010] Dimeric and oligomeric indancarboxylate compounds are widely disclosed in US2019 / 231909 but without any indication of application.

[0011] Fluorescent image generators, such as 1-(2-hydroxyethyl)-2,6-dioxo-1,3-dihydroisonicotinic acid and 1-oxo-1H-pyrido[2,1-b][1,3]benzothiazol-3 Petition 870250079624, dated 05 / 09 / 2025, pages 639 / 725 3 / 67 carboxylic acids are disclosed in WO2016 / 164437, for example. WO2016 / 164437 describes the detection methods described herein. In some claims, a detection method comprises discarding a fluorophore into a biological environment, wherein the fluorophore comprises a dioxopyridine ring (DPR) or a thiazolopyridine acid (TPA).

[0012] The present invention seeks to provide FWA or optical brightener with functionality comparable to the industry standards mentioned above, but with fewer environmental disadvantages. Brief Description of the Invention

[0013] According to a first aspect of the invention, a fluorescent whitening agent or optical brightener of formula (I) is provided with the structure: in which: A is CR1R2(CH2)n where R1 is H, CH2OH or COZ, R2 is H or CH2OH and where n is 1 or 2, or where A is an optionally substituted aromatic or heteroaromatic ring fused with N and X where N and X are respectively bonded to adjacent carbon atoms in the ring; X is O, S, or NH; Y is Z or X'L; or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4, NR42, where M is selected from an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, or an ether. Petition 870250079624, dated 05 / 09 / 2025, pp. 640 / 725 4 / 67 linear or branched alkyl, a polyester with 2 to 1000 repeating units or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; or each R4 is selected independently from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl or 2-aminoethyl; alternatively, NR42 represents a heterocyclic ring, for example, morpholine; and wherein Y is X'L; X' is O, S, or NH; and L represents a portion of the ligand connecting m repeating units of formula I, having X' as defined above in place of Y.

[0014] In embodiments where A is an optionally substituted heteroaromatic ring, A is preferably a pyridine ring.

[0015] In embodiments where R3 represents a linear or branched alkyl group, R3 is preferably selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, or 2-ethylhexyl.

[0016] In embodiments where R3 represents an alkyl alcohol, R3 is preferably selected from methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, dodecanol, or stearyl or oleyl alcohol.

[0017] In embodiments where R3 represents an aryl, R3 is preferably phenyl, and in embodiments where R3 represents an alkaryl, R3 is preferably selected from benzyl or ethylphenyl.

[0018] In embodiments where R3 represents a linear or branched alkyl alcohol, R3 is preferably selected from 4-hydroxybutyl.

[0019] In embodiments where R3 represents a linear or branched alcohol polyol, R3 is preferably a diol or triol. In most preferable cases, R3 can be selected from 2,3-dihydroxypropyl, or 2-hydroxy-1(hydroxymethyl)ethyl.

[0020] In embodiments where R3 represents a hydroxyalkylamine, R3 is preferably selected from triethanolamine, N-methyldiethanolamine or triisopropanolamine. Petition 870250079624, dated 05 / 09 / 2025, pages 641 / 725 5 / 67

[0021] In embodiments where R3 represents a polyhydric alcohol, R3 is preferably glycerol.

[0022] In embodiments where R3 represents a sugar, R3 is preferably selected from dextrose, fructose, galactose, glucose, lactose, maltose or sucrose.

[0023] In embodiments where R3 represents a linear or branched alkyl ether, R2 is preferably selected from 2-(2-hydroxyethoxy)ethyl, 2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 2-[2-(2-hydroxy-1-methylethoxy)-1-methylethoxy]-1-methylethyl, 3-(3-hydroxypropoxy)propyl, 3-[3-(3-hydroxypropoxy)propoxy]propyl, 4-(4-hydroxybutoxy)butyl, 4-[4-(4-hydroxybutoxy)butoxy]butyl, 2-(2-methoxyethoxy)ethyl, or 2-[2(2-methoxyethoxy)ethoxy]ethyl.

[0024] In embodiments where R3 represents a polyester or a polyoxyalkylene with 2 to 1000 repeating units, it may be a homopolymer or a copolymer.

[0025] The L ligand can be derived from an alcohol, in which case X' is the oxygen of the precursor alcohol; or it can be derived from an amine, in which case X' is the nitrogen of the precursor amine.

[0026] In dimeric or oligomeric compounds according to the invention, m is 2 or more, preferably 3 to 20, preferably 3.

[0027] The linker L may consist of any of the ethylenes, propylenes or C4 to C12 alkylenes, a polyester chain with 0 to 1000 repeating units being a homopolymer or copolymer, or a polyoxyalkylene chain with 0 to about 1000 repeating units being a homopolymer or copolymer, triethanolamine, glycerol or sugar.

[0028] According to a second aspect of the invention, a fluorescent whitening agent or optical brightener of formula (II) is provided with the structure: Petition 870250079624, dated 05 / 09 / 2025, pp. 642 / 725 6 / 67 where Y is Z or X'L; Z is OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, M represents an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alcoholic polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units, or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; R4 is selected independently from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl or 2-aminoethyl; alternatively, NR32 represents a heterocyclic ring, for example, morpholine; and R is H, CHR5R6, R5, R6, an alkyl sulfonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) wherein each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl or cyano, optionally wherein R4 and R5 are the same or different, and is 1 or 2; where Y is X'L; X' is O, S, or NH; and L represents a ligand portion connecting m repeating units of a variant of formula II in which X', as defined above, is present in place of Y.

[0029] In embodiments where R3 represents a linear or branched alkyl group, R3 is preferably selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, or 2-ethylhexyl.

[0030] In embodiments where R3 represents an alkyl alcohol, R3 is preferably selected from methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, dodecanol, or stearyl or oleyl alcohol. Petition 870250079624, dated 05 / 09 / 2025, pages 643 / 725 7 / 67

[0031] In embodiments where R3 represents an aryl, R3 is preferably phenyl, and in embodiments where R3 represents an alkaryl, R3 is preferably selected from benzyl or ethyl phenyl.

[0032] In embodiments where R3 represents a linear or branched alkyl alcohol, R3 is preferably selected from 4-hydroxybutyl.

[0033] In embodiments where R3 represents a linear or branched alcohol polyol, R3 is preferably a diol or triol. In most preferable cases, R3 can be selected from 2,3-dihydroxypropyl, or 2-hydroxy-1(hydroxymethyl)ethyl.

[0034] In embodiments where R3 represents a hydroxyalkylamine, R3 is preferably selected from triethanolamine, N-methyldiethanolamine or triisopropanolamine.

[0035] In embodiments where R3 represents a polyhydric alcohol, R3 is preferably glycerol.

[0036] In embodiments where R3 represents a sugar, R3 is preferably selected from dextrose, fructose, galactose, glucose, lactose, maltose or sucrose.

[0037] In embodiments where R3 represents a linear or branched alkyl ether, R3 is preferably selected from 2-(2-hydroxyethoxy)ethyl, 2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 2-[2-(2-hydroxy-1-methylethoxy)-1-methylethoxy]-1-methylethyl, 3-(3-hydroxypropoxy)propyl, 3-[3-(3-hydroxypropoxy)propoxy]propyl, 4-(4-hydroxybutoxy)butyl, 4-[4-(4-hydroxybutoxy)butoxy]butyl, 2-(2-methoxyethoxy)ethyl, or 2-[2(2-methoxyethoxy)ethoxy]ethyl.

[0038] In embodiments where R3 represents a polyester or polyoxyalkylene chain having from 2 to 1000 repeating units, it can be a homopolymer or a copolymer.

[0039] The ligand L can be derived from an alcohol, in which case X' is the oxygen of the precursor alcohol; or it can be derived from an amine, in which case X' is the nitrogen of the precursor amine.

[0040] In dimeric or oligomeric compounds according to the invention, m is 2 or more, preferably 3 to 20, preferably 3. Petition 870250079624, dated 05 / 09 / 2025, pp. 644 / 725 8 / 67

[0041] The linker L may consist of any of the C4 to C12 ethylenes, propylenes or alkylenes, a polyester chain with 0 to 1000 repeating units being a homopolymer or copolymer, or a polyoxyalkylene chain with 0 to about 1000 repeating units being a homopolymer or copolymer, triethanolamine, glycerol or sugar.

[0042] The FWAs and optical brighteners of the invention are preferably formulated for use as fluorescent brightening agents or optical brighteners, as the case may be. Typically, this formulation involves supplying the active ingredient (FWA or optical brightener) together with at least one auxiliary compound normally present in fluorescent brightening or optical brightening formulations. These auxiliary compounds may be selected, for example, from one or more detergents, bleaches, carrier compounds, stabilizers and / or dispersants.

[0043] The invention also provides for the use of the aforementioned compounds as fluorescent whitening agents or optical brighteners.

[0044] The invention also provides a fluorescent whitening or optical brightening formulation comprising said fluorescent whitening or optical brightening agent and at least one detergent, bleach, carrier compound, stabilizer and / or dispersant.

[0045] Also provided according to the invention is a method for providing fluorescent brightening or optical glow to a substrate comprising contacting the substrate with one or more of the aforementioned compounds under conditions effective to allow chemical and / or physical bonding of one or more compounds on the substrate. Detailed Description of the Invention

[0046] Current industry-standard fluorescent brightening agents or optical brighteners, including DAS-1, DAS-2, DSPB, and FB28, absorb ultraviolet light in the 340–370 nm region and emit visible blue light in the 420–470 nm region. To achieve this effect, elongated conjugated molecular systems are required to provide an adequate number of π-electrons. Petition 870250079624, dated 05 / 09 / 2025, pages 645 / 725 9 / 67 in the conjugated aromatic system, to allow for a suitable energy transition that achieves emission at 420-470 nm in de-excitation. As demonstrated by the chemical structures of the current industry standard, this typically requires elongated aromatic systems based predominantly on carbon and hydrogen, which have high molecular weights.

[0047] Derivatives of pyridone and citric acid are known to achieve similar π-electron counts and also emit visible blue light in the 420–470 nm range. These derivatives, which have substantially lower molecular weights, achieve this through the incorporation of heteroatoms, such as nitrogen and oxygen.

[0048] The excitation and de-excitation properties of the fluorescent brightening agents or optical brighteners of the invention are well understood, with RSC Adv., 2015, 5, 34795 attributing fluorescence in the 420 to 470 nm range to compounds similar to π*transitions in the same carbon-oxygen double bond found in pyridone-based scaffolds and citric acid-zinc. It is believed that the carboxyl groups, and in particular the carboxylic acid groups, present in the structures of formulas (I) and (II) of the present invention contribute to the necessary number of π-electrons associated with fluorescence in the desired range.

[0049] As a result, the disclosed structures are advantageous compared to current industry standard fluorescent brightening agents and optical brighteners, as they provide comparable fluorescence using a smaller compound with lower molecular weight. Furthermore, improved functionalization of the formula (I) and (II) structures to modulate application performance can be easily achieved, with little effect on the fluorescent behavior of the fluorescent brightening agent or optical brightener.

[0050] There are several factors that govern the effectiveness of FWA or optical brightener according to the invention. Petition 870250079624, dated 05 / 09 / 2025, pages 646 / 725 10 / 67

[0051] These compounds typically absorb ultraviolet light in the 340 to 370 nm region and emit visible light in the 420 to 470 nm region. The quantum yield of these compounds in this respect is preferably at least about 30%, more preferably at least about 40%, even more preferably at least about 50%, preferably at least about 60%.

[0052] The FWAs or optical brighteners of the present invention exhibit much higher relative quantum yields than current industry standards. For example, only DSPB provides a comparable value exceeding 70%. Therefore, the FWAs or optical brighteners described in the present invention are advantageous over current standards because similar fluorescence performance can be achieved with a much lower molecular weight, which in turn can lead to a lower charge of the FWA or optical brightener in the final application. Lower charges can mitigate any potential adverse effects associated with the compound.

[0053] The FWA or optical brightener of the invention typically exhibits good substantivity on cellulosic fabrics, for example, retaining at least 30% of the filler after a typical wash cycle.

[0054] FWAs or optical brighteners according to the invention can be sustainably produced from readily available starting materials using environmentally friendly reagents. Therefore, a fluorescent brightening agent or optical brightener derived from the condensation of a di- or polycarboxylic acid and an amine – in particular, between a di- or polycarboxylic acid and an amino acid or amino acid derivative – is also provided according to the invention.

[0055] Current industry-standard FWAs and optical brighteners, including DAS-1, DAS-2, DSPB, and FB28, possess large, high molecular weight conjugated aromatic systems that have limited capacity for oxidation or hydrolysis, making them less biodegradable. Recent studies have identified fluorescent brightening agents as a source Petition 870250079624, dated 05 / 09 / 2025, pp. 647 / 725 11 / 67 emerging pollution in urban wastewater, which negatively impacts aquatic ecosystems and water resources. The Marine Pollution Bulletin, 2022, 178, 113559 identifies FWAs as a pollutant of emerging concern, as they are present in wastewater, sometimes at concentrations comparable to the upper range of better-studied wastewater pollutants such as pharmaceuticals (approx. 10-1000 ng / L). In particular, data from Sweden showed that DAS-2 was always detected in effluents when analyzed and present at comparatively high median concentrations of 1500 ng / L.

[0056] In comparison, the FWAs and optical brighteners according to the invention have smaller fluorescent cores and are therefore more biodegradable, as they are more prone to biological attack, while at the same time providing sufficient stability to oxidation and hydrolysis to be used in the intended applications.

[0057] The molecular weight of the FWAs and optical brighteners of the present invention is preferably less than about 1000, less than about 750, less than about 500, less than about 400, less than about 300 or less than about 200.

[0058] Estimating biodegradation based on chemical structures is complex due to variations in the physicochemical properties of organic compounds. Predictive methods for estimating biodegradation previously relied on metabolic pathways and microbial diversity. However, more recently, predictive methods use group contribution, QSAR, or machine learning methods.

[0059] As detailed in Ecotoxicol. Environ. Saf. 1989, 18, 252-267, based on a survey of 22 biodegradation experts, a hierarchy was constructed to represent the approximate order in which various groups were seen as contributing to aerobic biodegradability: ester = amide = anhydride > hydroxyl > carboxylic acid = epoxy = site of unsaturation > benzene ring = methyl = methylene group. The general inference was that compounds that were already partially oxidized were generally considered more prone to Petition 870250079624, dated 05 / 09 / 2025, pages 648 / 725 12 / 67 biological attack than those that were not partially oxidized, all other things being equal, and that hydrolytic chemicals are considered even more easily degradable. The time required for final degradation was generally deduced from consideration of molecular weight, branching, halogenation, functional groups, solubility, and other factors.

[0060] Advantageously, FWAs and optical brighteners according to the invention are biodegradable. Preferably, they contain at least one functional group that is not oxidized or that is only partially oxidized and is therefore oxidizable or even more oxidizable. Preferably, they contain at least one hydrolyzable group.

[0061] Therefore, an FWA or optical brightener comprising at least one labile group is also provided according to the invention. Inherently biodegradable fluorescent brightening agents can be defined as > 20% but < 60% biodegradability in water, as measured by the OECD Standard Test 301A-F. A readily biodegradable fluorescent brightening agent or optical brightener can be characterized by the ability of the material to biodegrade rapidly and completely in water (either > 70% removal of dissolved organic carbon, > 60% of theoretical carbon dioxide or > 60% of theoretical oxygen demand, depending on the OECD Standard Test 301A-F methods) within a 10-day window within 28 days.

[0062] FWAs and optical brighteners according to the invention are preferably stable at relatively high pH, ​​for example, from about pH 7 to about pH 10, pH 7.5 to about 9.5, typical conditions in a laundry wash.

[0063] FWAs and optical brighteners according to the invention are preferably UV stable.

[0064] FWAs and optical brighteners according to the invention are preferably oxidatively stable in a conventional wash cycle.

[0065] According to the invention, preferred examples of fluorescent brightening agents and optical brighteners (Table 1) are: Petition 870250079624, dated 05 / 09 / 2025, pp. 649 / 725 13 / 67 Table 1. Codes Structure and description 1a Oχ / Oχ y ra In embodiments of general formula 1a, Ra can be an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl, or a benzyl group. 1b O\ / O / / OH y^ y ' 'n XX O^N^s In embodiments of general formula 1b, the ester can be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as a polyoxyethylene chain where n is 2-20. 1c Ox / 0. In realizations of the general formula 1c, Rc can be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. 1d H Ox ,N. y Rd XX °^X / s Petition 870250079624, dated 05 / 09 / 2025, pp. 650 / 725 14 / 67 In embodiments of general formula 1d, Rd can be an alkyl group, such as butyl, pentyl, hexyl, heptyl, or octyl, or Rd can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. 2a O\ / O. y re O^N^o HO \ OH In embodiments of general formula 2a, Re can be an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl, or a benzyl group. 2b O\ / θΖ / OH oí ' 'n fjl O^N^q HO \ OH In embodiments of general formula 2b, the ester may be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as for example a polyoxyethylene chain where n is 2-20. 2c O\ y rf XjL O^N^o HO \ OH In embodiments of general formula 2c, Rf may be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO5M, in Petition 870250079624, dated 05 / 09 / 2025, pages 651 / 725 15 / 67 where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. 2d HV Rg O^N^q HO \ OH In embodiments of the general formula 2d, Rg can be an alkyl group, such as butyl, pentyl, hexyl, heptyl or octyl, or Rg can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. 3a CK ,O^ Y Rh O^N^s O^ / °^Rh In embodiments of the general formula 3a, the group at each Rh position can independently be hydrogen or an alkyl, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl or a benzyl group. In embodiments of the general formula 3b, the pendant group can independently be hydrogen or the ester of an alkyl alcohol. Petition 870250079624, dated 05 / 09 / 2025, pages 652 / 725 16 / 67 comprising a polyoxyalkylene chain with repeating units, such as a polyoxyethylene chain where n is 2-20. 3c O\ / 0. y Ri AO^N^s 0==: / OR, In embodiments of the general formula 3c, the group at each Ri position can independently be hydrogen or an alkyl sulfonate or sulfonic acid of general formula -(CH2)qSO3M, where q is 15 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. In embodiments of the general formula 3d, the group at each Rj position can independently be a hydroxyl group or an alkylamine group (-NH-R), such as butylamine, pentylamine, hexylamine, heptylamine, or octylamine, or each Rj can independently be a hydroxyl group or an amino alcohol (-NHR-OH), such as 2-hydroxyethylamine, 2-hydroxy-1-(hydroxymethyl)ethylamine, or 2,3-dihydroxypropylamine. Petition 870250079624, dated 05 / 09 / 2025, pages 653 / 725 17 / 67 In embodiments of general formula 4a, Rk can be ethyl alcohol (CH2CH2OH), isopropyl alcohol (-CH(CH2OH)2), 2-hydroxypropyl (CH2CH(OH)CH3), benzyl (-CH2C6H5), NN-dimethylethyl (CH2CH2N(CH3)2), propenyl (-CH2CHCH2), propyl (-CH2CH2CH3) or ethyl sulfonate (-CH2CH2SO3Na); and Rl may be hydrogen, an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl or a benzyl group, or Rl may be an alcohol or branched alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl, or Rl may be 2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 2-[2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 3-(3-hydroxypropoxy)propyl, 3-[3-(3-hydroxypropoxy)propoxy]propyl, 4-(4-hydroxybutoxy)butyl, 4-[4-(4-hydroxybutoxy)butoxy]butyl, 2-(2-methoxyethoxy)ethyl or 2-[2-(2methoxyethoxy)ethoxy]ethyl.4b O\ / 07 ,OH ' 'n O^^N^^O 1 Rk In embodiments of the general formula 4b, Rk can be ethyl alcohol (CH2CH2OH), isopropyl alcohol (-CH(CH2OH)2), 2-hydroxypropyl (CH2CH(OH)CH3), benzyl (-CH2C6H5), NN-dimethylethyl (CH2CH2N(CH3)2), propenyl (-CH2CHCH2), propyl (-CH2CH2CH3) or ethyl sulfonate (-CH2CH2SO3Na); and the ester can be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as, for example, a polyoxyethylene chain where n is 2-20. Petition 870250079624, dated 05 / 09 / 2025, pages 654 / 725 18 / 67 4c °^°-R η KM 1 Rk In realizations of the general formula 4c, Rk can be ethyl alcohol (CH2CH2OH), isopropyl alcohol (-CH(CH2OH)2), 2-hydroxypropyl (CH2CH(OH)CH3), benzyl (-CH2C6H5), NN-dimethylethyl (CH2CH2N(CH3)2), propenyl (-CH2CHCH2), propyl (-CH2CH2CH3) or ethyl sulfonate (-CH2CH2SO3Na); and Rm can be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as, for example, methanesulfonic acid or ethanesulfonic acid. In embodiments of the general formula 4d, Rk can be ethyl alcohol (-CH2CH2OH), isopropyl alcohol (-CH(CH2OH)2), 2-hydroxypropyl (-CH2CH(OH)CH3), benzyl (-CH2C6H5), N-N-dimethylethyl (-CH2CH2N(CH3)2), propenyl (-CH2CHCH2), propyl (CH2CH2CH3), or ethyl sulfonate (-CH2CH2SO3Na); and Rn can be an alkyl group, such as butyl, pentyl, hexyl, heptyl, or octyl, or Rn can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. Petition 870250079624, dated 05 / 09 / 2025, pp. 655 / 725 19 / 67 In a particular embodiment of the general formula 4e, Y can be ethyl alcohol (-CH2CH2OH), isopropyl alcohol (-CH(CH2OH)2), 2-hydroxypropyl (-CH2CH(OH)CH3), benzyl (-CH2C6H5), N-N-dimethylethyl (-CH2CH2N(CH3)2), propenyl (-CH2CHCH2), propyl (CH2CH2CH3) or ethyl sulfonate (-CH2CH2SO3Na); and the NH group is further substituted. 5a 0 CL O 0 0 In embodiments of general formula 5a, the group at each Ro position may independently be hydrogen, an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl or a benzyl group, or the group at each Ro position may be an alcohol or branched alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl.5b O-, / 0 / / OH Y^ of ' 'n O^^N'^O o^^ o7 / OH oí ' 'n In embodiments of the general formula 5b, each ester can independently be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as a polyoxyethylene chain where n is 2-20. Petition 870250079624, dated 05 / 09 / 2025, pp. 656 / 725 20 / 67 5c Ο^^N'^'Ο ο^^ Ox RP In embodiments of the general formula 5c, the group at each Rp position can independently be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. 5d HO\ / N^ Rq o o. HN. rq In embodiments of the general formula 5d, the group at each Rq position can independently be an alkyl group, such as butyl, pentyl, hexyl, heptyl or octyl, or the group at each Rq position can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl or 2,3-dihydroxypropyl. In embodiments of general formula 6a, the group at each Rr position can independently be hydrogen, an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, or a branched alkyl group, such as isopropyl, 2- Petition 870250079624, dated 05 / 09 / 2025, pages 657 / 725 21 / 67 ethylhexyl or a benzyl group, or the group at each Rr position may be an alcohol or branched alcohol, such as, for example, 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. 6b Ox / 07 / x ΌH� Y oj^^ Jx / 0 Λχ 07 / x Vx / OH o ^o o7 5 θχ n ΌH� In embodiments of the general formula 6b, each ester may independently be the ester of an alkyl alcohol comprising a polyoxyalkylene chain with repeating units, such as, for example, a polyoxyethylene chain where n is 2-20. 6c ß^^N'^I JxxO RSx Àx ßχ O Rs In embodiments of the general formula 6c, the group at each Rs position can independently be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. Petition 870250079624, dated 05 / 09 / 2025, pages 658 / 725 22 / 67 6d H RT J^^O RT. HN. N RT H In embodiments of general formula 6d, the group at each Rt position may independently be an alkyl group, such as butyl, pentyl, hexyl, heptyl, or octyl, or the group at each Rt position may be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. 7a Xi ° Xs \ / m In embodiments of general formula 7a, the linker group L may be selected from any of the following alkyl groups, such as propyl, butyl, pentyl, hexyl, heptyl, octyl, or branched linkers, such as 2-hydroxyethylaminodiethane, 3-hydroxypropyl, or 2-hydroxypropyl. 7b o / —λ / ° <z>o \ \\___o _-Z / L / = / x° In embodiments of general formula 7b, the linking group L can be selected from linear chain or branched alkyl or alcohol groups, such as, for example, ethyl, 1-methylethyl, propyl, 2-methylpropyl, 2-hydroxypropyl, butyl, and the number of repeating units, n, can be selected from 2-9. Petition 870250079624, dated 05 / 09 / 2025, pages 659 / 725 23 / 67 7c 0 0 O\ Aχ / Jí Y, .0. / -0 V γ-' Ό lA 07 ' Ól χΊ Xá Ο^^νΎ O^^N'^'g In embodiments of the general formula 7c, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 7d IO 0 JAI AO^N 'S crA^g In embodiments of the general formula 7d, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 7e 0χΧ>7 OLO^ / OYYYYYY / k 0 ° Y\ Ã1 X 1 oY 'S In embodiments of the general formula 7e, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 7f \ ° o '— / o In specific embodiments of the general formula 7f, the linking group L can be selected from linear chains, chains Petition 870250079624, dated 05 / 09 / 2025, pages 660 / 725 24 / 67 Branched alkyl or alcohol groups, or heterocyclic rings, or a combination thereof. 8a 4^ ° / — \Z-\ O '-- / \--Λ O ξ y In embodiments of the general formula 8a, the linker group L may be selected from any of the following alkyl groups, such as, for example, propyl, butyl, pentyl, hexyl, heptyl, octyl, or branched linkers, such as 2-hydroxyethylaminodiethane, 3-hydroxypropyl, or 2-hydroxypropyl. 8b oy O ,--b 7 z—' ov \ ° In embodiments of the general formula 8b, the linker group L may be selected from linear or branched chain alkyl or alcohol groups, such as, for example, ethyl, 1-methylethyl, propyl, 2-methylpropyl, 2-hydroxypropyl, butyl, and the number of repeating units, n, may be selected from 2-9. 8c O 0 CK / OV / O y / O Lb 0 / γ Ο^^Ν'^Ο Ο^^Ν'^Ο Petition 870250079624, dated 05 / 09 / 2025, pages 661 / 725 25 / 67 In embodiments of the general formula 8c, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 8d I oo O^^N'^O In embodiments of the general formula 8d, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 8e ß^,Y .0. L cÓ .0^, OTVYYYTO 0 Yx crY'Y cy Sq In embodiments of the general formula 8e, the linking group L can be selected from ethyl, propyl, benzyl, furanyl; and the number of repeating units, n, can be selected from 2-10. 8f O'^'N'^'O o^^nY) In specific embodiments of the general formula 8f, the linking group L may be selected from linear chains, branched alkyl or alcohol chains, or heterocyclic rings, or a combination thereof. Petition 870250079624, dated 05 / 09 / 2025, pages 662 / 725 26 / 67 9a y Ru Xjj O^N^s O In embodiments of general formula 9a, Ru can be hydrogen or an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl, or a benzyl group. 9b O\ / 0 / ,OH y^ oí ' 'n χι O^N^s In embodiments of general formula 9b, the ester can be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as a polyoxyethylene chain where n is 2-20. 9c 0.^ y rv O^N^SO In realizations of the general formula 9c, Rv can be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid. Petition 870250079624, dated 05 / 09 / 2025, pages 663 / 725 27 / 67 9d H 0. Rw O^N^sw In embodiments of general formula 9d, Rw can be an alkyl group, such as butyl, pentyl, hexyl, heptyl or octyl, or Rw can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl. 10a o. y Rx ß^N^χ N λ In embodiments of general formula 10a, Rx can be hydrogen or an alkyl group, such as methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, a branched alkyl group, such as isopropyl, 2-ethylhexyl or a benzyl group; and X can be selected from O, S or NH. The embodiment shown depicts N in position 3. However, in other embodiments, N may be in position 4, 5, or 6 of the aromatic ring. 10b O\ ,0 / / OH YO^N^x N Λ In embodiments of the general formula 10b, the ester may be the ester of an alkyl alcohol, comprising a polyoxyalkylene chain with repeating units, such as for example a Petition 870250079624, dated 05 / 09 / 2025, pages 664 / 725 28 / 67 Polyoxyethylene chain where n is 2-20; and X can be selected from O, S, or NH. The embodiment shown displays N at position 3. However, in other embodiments, N may be at position 4, 5, or 6 of the aromatic ring. 10c O\ / 0^ y ry ß^N^χ N λ In embodiments of the general formula 10c, Ry can be an alkyl sulfonate or sulfonic acid of general formula (CH2)qSO3M, where q is 1-5 and M is H or a metal, such as methanesulfonic acid or ethanesulfonic acid; and X can be selected from O, S, or NH. The embodiment shown displays N at position 3. However, in other embodiments, N may be at position 4, 5, or 6 of the aromatic ring. In embodiments of the general formula 10d, Rz can be an alkyl group, such as butyl, pentyl, hexyl, heptyl, or octyl, or Rz can be an alcohol, such as 2-hydroxyethyl, 2-hydroxy-1-(hydroxymethyl)ethyl, or 2,3-dihydroxypropyl; and X can be selected from O, S, or NH. The embodiment shown has N in the 3 position.However, in other embodiments, the N may be in position 4, 5, or 6 of the aromatic ring. Petition 870250079624, dated 05 / 09 / 2025, pp. 665 / 725 29 / 67

[0066] In specific embodiments of the invention, the binder may be able to support multiple fluorescent brightening cores, examples of such binders are given below, which may be combined at each position with one of the general cores, (I) and (II). Petition 870250079624, dated 05 / 09 / 2025, pp. 666 / 725 30 / 67

[0067] Fluorescent brightening agents or optical brighteners, according to the present invention, have excellent chemical stability at relatively high pH, ​​for example, the typical pH of a powdered soap formulation. They also have very adequate thermal stability in such applications, and can be prepared (see below) by synthetic methods involving temperatures up to 130°C.

[0068] The fluorescent whitening agents or optical brighteners according to the present invention can be used in a variety of applications, including, but not limited to, laundry, dishwashing, papermaking, personal care (cosmetics, hair care, etc.), paints and coatings, and adhesives. In these applications, the fluorescent whitening agent or optical brightener is able to make the material, such as cotton, appear whiter, while masking the yellowing of aging.

[0069] The fluorescent brightening agent or optical brightener can be used in all types of formulations, such as liquids, powders, sheets or bars, in different proportions and loads, as appropriate.

[0070] Summary

[0071] The fluorescent brightening agent or optical brightener can be prepared from readily available starting materials such as citric acid or citrazine acid. The preparation of the target compounds of the present invention (Scheme 1) is advantageously more environmentally acceptable as a result of the use of common and renewable building blocks such as citric acid, manufactured on a large scale by fermentation.

[0072] Each core structure can be readily synthesized by heating citric acid in the presence of water, with the water itself as the main byproduct. The water-based synthesis is cleaner, more environmentally friendly and highly scalable.

[0073] Further functionalization of the core units to modify and / or improve the substantivity of the resulting fluorescent whitening agent or Petition 870250079624, dated 05 / 09 / 2025, pages 667 / 725 31 / 67 optical brightener in the desired application can be readily achieved by a second, easy reaction with alcohol or amine. Scheme 1: Representative synthetic route used for optical brighteners of the present invention, wherein Y is as defined in the first aspect of the invention, and X1 is any suitable exit group.

[0074] In comparison, the preparation of existing optical brighteners, such as references DAS 1, DAS 2 and FB28 (Scheme 2A), requires complex synthetic methods comprising 5 synthetic steps, as well as the use of environmentally undesirable materials such as precious metal catalysts and petrochemical-derived feedstocks. Similarly, the preparation of the optical brightener DSPB (Scheme 2B) requires complex synthetic steps involving environmentally undesirable and / or hazardous materials such as cyanuric chloride, trimethyl phosphite and dimethylformamide (DMF). Both families of molecules (Scheme 2A or Scheme 2B) utilize feedstocks derived from petrochemical products. Scheme 2A: Synthetic route used for optical brighteners of Petition 870250079624, dated 05 / 09 / 2025, pages 668 / 725 32 / 67 Scheme 2B: Synthetic route used for the current reference optical brightener DSPB. General Synthesis of Core Units of Fluorescent Bleaching Agents (bases for formula (I)) from Citric Acid

[0075] A mixture of citric acid (1 eq.) and corresponding amine (1 eq.) was dissolved in water (1 vol.). The reaction mixture was heated to 100°C to allow all the water to distill. The reaction temperature was then increased to 140°C to melt the resulting residues, the molten mixture was then stirred for 16 hours and the reaction water was allowed to distill. The resulting resinous material was cooled to <100°C before adding fresh water (1 vol.). The mixture was then cooled to room temperature with vigorous stirring to disperse the product before filtration. The isolated solids were washed with fresh water (0.5 vol.) before being dried in a vacuum oven to obtain the final product. Synthesis of the Central Unit of the Fluorescent Whitening Agent (1a)

[0076] A mixture of citric acid (200 g, 1.05 mol) and cysteamine (80.3 g, 1.05 mol) was dissolved in water (300 ml). The reaction mixture was heated to 100°C to allow all the water to distill. The reaction temperature was then increased to 140°C to melt the resulting residues with stirring for 4 hours. The temperature was then increased to 160°C and the molten mixture was then stirred for 16 hours and the reaction water was distilled. The resulting resinous material was cooled <100°C before adding fresh water (300 ml). Petition 870250079624, dated 05 / 09 / 2025, pages 669 / 725 33 / 67 The mixture was then cooled to room temperature with vigorous stirring to disperse the product before filtration. The isolated solids were washed with fresh water (150 ml) before drying in a vacuum oven to give the final product as a yellow powder with a yield of 64.5% (131.4 g, 0.68 mol).

[0077] Analytical data: HPLC purity: 99.7%; LCMS (+ve ion): m / z 198.1 Synthesis of the Central Unit of the Fluorescent Whitening Agent (3a)

[0078] A mixture of citric acid (200 g, 1.05 mol) and cysteine ​​(127.2 g, 1.05 mol) was dissolved in water (325 ml). The reaction mixture was heated to 100°C to allow all the water to be distilled. The reaction temperature was then increased to 140°C to melt the resulting residues, the molten mixture was then stirred for 16 hours and the reaction water was allowed to distill. The resulting resinous material was cooled to <100°C before the addition of fresh water (325 ml). The mixture was then cooled to room temperature, with vigorous stirring, to disperse the product before filtration. The isolated solids were washed with fresh water (150 ml) before being dried in a vacuum oven to obtain the final product as a yellow powder with a yield of 61% (154.7 g, 0.64 mol).

[0079] Analytical data: HPLC purity: 99.8%; LCMS (+ve ion): m / z 242.2;1H NMR (DMSO-d6, 400 = MHz, d): 6.59 (s, 1H), 6.52 (s, 1H), 5.46 (d, 1H), 3.92 (t, 1H), 3.60 ppm (d, 1H);13C{1H} NMR (DMSO-d6, 75 MHz, d): 169.2, 165.6, 160.7, 150.2, 142.7, 114.8, 97.9, 62.6 ppm. Synthesis of the Central Unit of the Fluorescent Whitening Agent (4a)

[0080] A mixture of citric acid (200 g, 1.05 mol) and benzylamine (127.2 g, 1.05 mol) was dissolved in water (325 ml). The reaction mixture was heated under reflux for 16 hours. The reaction mixture was then dried under vacuum and ground to provide the final product as a yellow powder with near quantitative yield and good purity. Esterification of the Central Unit of the Fluorescent Whitening Agent (1a) with Ethanol

[0081] A mixture of FWA 1a (5 g, 0.026 mol) and p-toluenesulfonic acid (0.04 g, 0.002 mol) was suspended in industrial methylated spirits (IMS, also Petition 870250079624, dated 05 / 09 / 2025, pp. 670 / 725 34 / 67 called Industrial Denatured Alcohol, IDA, 15 ml) and heated to reflux before stirring for 24 hours. The reaction was then allowed to boil dry to remove water from the reaction. Fresh IMS (15 ml) was then added to the reaction and reflux continued for another 24 hours. The reaction mixture was then cooled and the solvent removed under reduced pressure to give the target ester a near-quantitative yield as a beige powder.

[0082] Analytical data: HPLC purity: 95.8%; LCMS (+ve ion): m / z 226.2 Esterification of Fluorescent Brightening Agent Core Units with Low Boiling Point Alcohols (<100°C)

[0083] A prepared FWA core mixture (1 eq.) was suspended in alcohol (3 vols.) and heated under reflux before stirring for 24 hours. The reaction was then allowed to boil dry to remove water from the reaction. Fresh alcohol (3 vols.) was then added to the reaction and reflux continued for another 24 hours. The reaction mixture was then cooled and the solvent removed at reduced pressure to give the target ester a near-quantitative yield. Esterification of the Central Unit of the Fluorescent Whitening Agent with High Boiling Point Alcohols (>100°C)

[0084] A prepared FWA core mixture (1 eq.) was suspended in alcohol (1.1 eq. per carboxylic acid group) with p-toluenesulfonic acid (0.08 eq.). The resulting mixture was then heated to >100°C, with 130°C being the preferred reaction temperature, and the reaction water distilled over 16 hours. Excess alcohol was then removed under reduced pressure or azeotropic distillation, as appropriate. For alcohols with high boiling points, the desired esters were purified by column chromatography or acetone precipitation. Amidation of FWA Central 1a ethyl ester with ethylenediamine

[0085] A prepared sample of the ethyl ester of central FWA 1a (2.25 g, 0.01 mol) was suspended in industrial methylated alcohol (IMS, 15 ml) before adding ethylenediamine (1.17 g, 0.02 mol) to give an instant orange color. The resulting mixture was heated under reflux and stirred for 16 hours. The reaction was then cooled before removing the excess alcohol under reduced pressure to Petition 870250079624, dated 05 / 09 / 2025, pp. 671 / 725 35 / 67 to give the desired amide as a beige powder with a yield of 82% (1.91 g, 0.008 mol).

[0086] Analytical data: HPLC purity: 95.6%; LCMS (+ve ion): m / z 240.2 Amidation of Functionalized Fluorescent Whitening Agents

[0087] A prepared sample of the desired central FWA ethyl ester (1 eq.) was suspended in IMS (5 vols.) before adding the target amine (2 eq. per carboxylic acid group) at room temperature. The resulting mixture was heated under reflux and stirred for 16 hours. The reaction was then cooled before removing excess alcohol under reduced pressure to give the desired amide.

[0088] Vehicles

[0089] In concentrated and granular detergent compositions, the compositions are normally supplied to an end user for use as a diluted or dissolved solution. In such a solution, the pH to which a fluorescent whitening agent is exposed before use may be particularly high, which can give rise to storage problems, particularly with regard to storage stability. There is therefore a need for improved delivery compositions compatible with environmentally acceptable fluorescent whitening agents, particularly those agents defined according to the present invention.

[0090] Similarly, fluorescent bleaching agents can be incorporated into detergent compositions for washing fabrics. However, mere incorporation does not guarantee that the fluorescent bleaching agent will be able to be absorbed by a fabric being washed. One of the functions of a detergent composition is to absorb into the surfaces of fabric materials and adhere preferentially so that oils and other residues are removed. This is typically achieved using surfactants. Surfactants can be classified as anionic, non-ionic, and cationic. There is therefore a need for a formulation of a detergent composition for washing fabrics that incorporates a fluorescent bleaching agent so that the fluorescent bleaching agent can remain absorbed into the surface of a fabric material after a washing process. Petition 870250079624, dated 05 / 09 / 2025, pages 672 / 725 36 / 67 particularly when the washing process is followed by a rinsing process. There is therefore a need for a detergent composition for washing fabrics capable of providing environmentally acceptable fluorescent bleaching agents during a washing process, where they remain in-situ in the material after that process.

[0091] In particular, there is a need for delivery compositions that allow environmentally acceptable fluorescent bleaching agents, specifically those structures defined according to the present invention, which provide delayed release of the fluorescent bleaching agent at a specific point in the washing process. Specifically, at a point in a washing process where the fluorescent bleaching agent has the highest probability of adsorption onto a fabric. Alternatively, rapid release of the fluorescent bleaching agent or optical brightener may also be advantageous in certain circumstances, as it would allow the fluorescent bleaching agent to adsorb onto a fabric before significant concentrations of the surfactant, for example, are present in a washing method, so as to compete with the fluorescent bleaching agent for adsorption onto a fabric.

[0092] In one embodiment of the invention, detergent compositions for washing fabrics are provided. The detergent compositions for washing fabrics can be in several different forms, such as compositions for hand washing, machine washing, colorless clothes, and colored clothes.

[0093] Compositions that provide an oxidizing agent are widely used and can also give rise to stability problems for environmentally acceptable fluorescent bleaching agents, such as the structures defined in the present application. There is therefore a need for delivery compositions that mitigate or improve the problems caused by oxidizing agents present in fabric washing detergent compositions.

[0094] The aforementioned problems are particularly relevant for environmentally acceptable fluorescent bleaching agents due to Petition 870250079624, dated 05 / 09 / 2025, pages 673 / 725 37 / 67 chemical complexity of such molecules, to the fact that these molecules are present in small quantities and therefore inherently have a high surface area to volume ratio in a composition, and that compounds tailored to environmentally acceptable compositions generally have labile groups intended to be degraded to improve biodegradability.

[0095] Notably, chemical groups designed to improve biodegradability are typically more labile in the presence of an oxidizing agent or under high pH conditions, or combinations thereof.

[0096] Furthermore, fluorescent brightening agents used in detergent compositions are preferably present at low levels, for example, levels as low as 0.01%. It is important to emphasize that high concentrations, such as those caused by individual granules, are unfavorable as they can lead to uneven distribution. This is particularly exacerbated by sedimentation of a granular mixture, for example, during transport. There is therefore a need for delivery compositions that allow for uniform distribution throughout the composition, along with any other relevant detergent ingredients in the overall detergent composition, particularly a detergent composition for washing fabrics and, even more particularly, a detergent composition for washing granular and solid fabrics.

[0097] Consequently, in another embodiment of the present invention, a solid support composition of a fluorescent brightening agent composition comprising a support and a fluorescent brightening agent is provided, according to the above.

[0098] In such an embodiment, the fluorescent brightening agent or optical brightener may be absorbed by the vehicle structure. Furthermore, the fluorescent brightening agent or optical brightener may be present in the vehicle composition at less than 34% by weight.

[0099] In another embodiment, the fluorescent whitening agent or optical brightener may be present in the carrier composition between 1% and 34% by weight. In a preferred embodiment, the fluorescent whitening agent or brightener Petition 870250079624, dated 05 / 09 / 2025, pages 674 / 725 Optical 38 / 67 may be present in 15 to 30% by weight. Advantageously, this appears to result in less dust and less absorption of any liquid from the granule, particularly when the fluorescent brightening agent is supplied as a liquid.

[00100] The fluorescent brightening agents according to the present invention may be supplied in solid or liquid form. The fluorescent brightening agents may be particularly in liquid or low-melting-point form, making them difficult to handle and incorporate into products in which they may be present as adjuvants. Examples of such products may include detergents, such as fabric washing detergents, cosmetics, such as sunscreens, paper manufacturing, such as paper finishing, and a variety of other applications in which fluorescent brightening agents are incorporated. In these applications, the fluorescent brightening agents may be present in small amounts, typically less than 1% by weight, sometimes as low as 0.01% by weight.

[00101] In these applications, handling and incorporating these materials is more difficult. To overcome this challenge, it is advantageous to increase the weight and volume of the fluorescent bleaching agent by incorporating it into a vehicle. However, it is important that, particularly when the tissue bleaching agent is a liquid or a low-melting-point solid, it is fully incorporated into the vehicle. In particular, in embodiments of the invention, when this incorporation level is 34% by weight or less, the fluorescent bleaching agent or optical brightener can be advantageously incorporated into the interstices of a porous structure.

[00102] In embodiments of the present invention, the vehicle may be selected from one or more sodium carbonates, potassium carbonate, calcium carbonate, magnesium carbonate, cellulose, carboxymethylcellulose, polyvinyl alcohol of 100,000 or more repeating units, sodium silicate, polyvinylpyrrolidone of 50,000 or more repeating units, or a zeolite. In particular, these materials are compatible with detergent compositions. Petition 870250079624, dated 05 / 09 / 2025, pages 675 / 725 39 / 67

[00103] In preferred embodiments of the present invention, the vehicle may be a water-soluble inorganic salt. These salts have been found to disperse the fluorescent brightening agent more rapidly, particularly when incorporated into an aqueous medium.

[00104] In the present invention, the vehicle composition can be prepared by drying the fluorescent brightening agent and the support from a solution, as this allows a homogeneous mixture to be produced before the support composition is prepared in solid form by drying.

[00105] In the present invention, drying of the composition is preferably achieved by spray drying. Spray drying has been found to allow fluorescent brightening agents of relatively low solubility to be effectively combined with soluble components in the form of a carrier, in a substantially homogeneous manner. This is particularly useful when the fluorescent brightening agent is a liquid or a low-melting-point solid, as a homogeneous mixture with a solubilized carrier can be produced for spray drying, providing a dry, low-dust granule.

[00106] In the present invention, the vehicle composition can be prepared by drying the composition using a fluidized bed. The advantageous drying method is effective where fluorescent brightening agents are sensitive to high drying temperatures. This is particularly relevant because the fluorescent brightening agents according to the invention are readily biodegradable and generally have labile groups, such as esters, which makes them temperature-sensitive compared to conventional fluorescent brightening agents.

[00107] In the present invention, where the vehicle composition comprises an insoluble vehicle and a solid or low-solubility fluorescent brightening agent, it can be prepared by co-granulation of the vehicle and the fluorescent brightening agent with a binder. This process avoids high temperatures and is therefore advantageous due to the aforementioned problems regarding the stability of fluorescent brightening agents. The binder Petition 870250079624, dated 05 / 09 / 2025, pages 676 / 725 40 / 67 can be selected from sodium silicate or an organic polymer. In most preferred embodiments, the binder can be an organic polymer, in particular a polyvinyl alcohol or a polyvinyl alcohol copolymer. The polar nature of these polymers provides more homogeneous compositions than polymers with low polarities or hydrophilicities.

[00108] Polycarboxylic acid can also be an example of a suitable binder material, especially when there is an amine or amide functionality in the fluorescent brightening agent, as it provides better solubilization of the fluorescent brightening agent during the preparation of the vehicle composition.

[00109] Clearly, there is a synergistic effect between proteolytic enzymes and fluorescent bleaching agents and, therefore, in some other embodiments of the present invention, the vehicle composition may also include a proteolytic enzyme. This is particularly the case when the fluorescent bleaching agent comprises an amide functionality. Furthermore, there is a synergistic effect between lipolytic enzymes and fluorescent bleaching agents and, therefore, the vehicle composition may also include a lipolytic enzyme. This is particularly the case when the fluorescent bleaching agent comprises an ester functionality.

[00110] The fluorescent brightening agent or optical brightener may be a liquid at room temperature.

[00111] The fluorescent whitening agent or optical brightener may have a solubility of less than 1 g per liter in water at room temperature.

[00112] The vehicle may be in the form of a polymer sheet, which may form a sachet or pouch for a detergent composition.

[00113] Detergents

[00114] According to another aspect of the present invention, a detergent composition is provided comprising said fluorescent whitening agent or optical brightener.

[00115] The detergent composition may include a key surfactant, for example, an anionic, cationic, zwitterionic or non-ionic surfactant. Petition 870250079624, dated 05 / 09 / 2025, pages 677 / 725 41 / 67

[00116] In preferred embodiments, the detergent composition comprises nonionic surfactants.

[00117] Advantageously, nonionic surfactants have been found to provide a preferred base detergent composition for the deposition of fluorescent whitening agents or optical brighteners of the present invention.

[00118] In embodiments of the present invention, where the determining surfactant is a non-ionic surfactant, it may be selected from one or more rhamnolipids or sophorolipids. Commercial examples of such surfactants include, but are not limited to, BioLoop 56L, BioLoop 56L-PG, BioLoop 68L, BioLoop 68L-PG, BioLoop 84L and BioLoop 84L-PG.

[00119] In the present invention, the fluorescent whitening agents or optical brighteners preferably have an amide functionality.

[00120] It has been found that these fluorescent whitening agents or optical brighteners provide better adsorption on surfaces being cleaned by the detergent composition. Without wishing to be bound by theory, it is understood that some degree of positive charge on the amide may interact with negatively charged surfaces. It is conventionally understood that this is the case when items are being washed.

[00121] It has been found that the present invention can provide improved FWA or optical brightener deposition when used in relevant detergent compositions. It is assumed that the FWA or optical brightener co-adsorbs with the cationic surfactant on the surfaces being washed.

[00122] In compositions that use a positively charged surfactant, such as a cationic or zwitterionic surfactant, FWA or optical brightener preferably has Y as OH or OM, M being Na or K.

[00123] These FWAs or optical brighteners have been found to provide better deposition, possibly due to the combination of the negatively charged FWA or optical brightener and the positively charged surfactant. Petition 870250079624, dated 05 / 09 / 2025, pp. 678 / 725 42 / 67 which together provide better surface adsorption. This is particularly beneficial for detergent compositions, such as fabric softeners.

[00124] In the present invention, the pH of the detergent composition is preferably in the range of pH 8 to 10. A pH in this range is particularly beneficial for the adsorption of ionizable FWA or optical brightener.

[00125] In the present invention, the detergent composition is preferably a laundry detergent composition, including fabric softeners, bleaching agents, pre-treatment agents, as well as conventional solid, liquid, gel, and bag detergent compositions, as well as light and heavy 'white' and 'colored' detergent compositions.

[00126] In the present invention, the detergent composition may preferably be a fabric washing detergent composition selected from one or more laundry detergents, fabric softeners, bleaches, or laundry aids (such as a bleaching agent).

[00127] In the present invention, the detergent composition preferably comprises a proteolytic enzyme and the FWA or optical brightener comprises an amide linkage.

[00128] The detergent composition of the present invention may also include a lipolytic enzyme, especially in embodiments in the FWA or optical brightener comprising an ester linkage.

[00129] The detergent composition of the present invention may be in the physical form of a powder (granules), liquid, gel, sachet, tablet or solid sheet.

[00130] Preferably, the physical form is solid. This is particularly the case for FWA or optical brightener, where m is 3 or more and L is a polymer. Such embodiments provide an FWA or optical brightener in a solid form that is compatible with other solids and is not subject to hydrolysis in the undiluted state. When the solid is diluted, as during washing, components of the detergent composition, such as enzymes or pH agents, may Petition 870250079624, dated 05 / 09 / 2025, pp. 679 / 725 43 / 67 trigger hydrolysis, which releases FWA or optical brightener into the washing composition.

[00131] Included within the scope of the invention are detergent compositions selected from one or more laundry detergents, fabric softeners, bleaches or laundry aids (such as a whitening agent).

[00132] The present invention, therefore, further provides a solid composition of a fluorescent whitening agent or optical brightener comprising a vehicle and a fluorescent whitening agent or optical brightener as described above.

[00133] The compounds according to the present invention may be capable of providing a fluorescent brightening effect or optical glow, in addition to being readily, ultimately, or inherently biodegradable. All compounds may have a common renewable building block, which makes their production environmentally friendly. Furthermore, the compounds may have one or more of the following characteristics: being substantive to the fabric, such as natural materials, including cotton and cellulose; being compatible with synthetic fabric materials; providing peak fluorescent output in the blue (450 and 495 nm) or green (495-570 nm) portions of the visible spectrum; providing high fluorescence in solid form and in solution; providing high fluorescence when absorbed into a fabric and solution; and / or providing greater absorption into cotton than 2,2'-stilbenedisulfonic acid.

[00134] Other applications of fluorescent brightening agents, as defined in the present invention:

[00135] Fabrics

[00136] FWA or optical brightener of the present invention can be used in the manufacture of fabrics.

[00137] The FWA or optical brightener of the present invention can be used in cotton finishing processes. Preferably in the treatment of grey fabric (loom state) into finished fabric.

[00138] FWA or optical brightener of the present invention can be used in melt-spun synthetic fibers. Petition 870250079624, dated 05 / 09 / 2025, pages 680 / 725 44 / 67

[00139] Paper

[00140] FWA or optical brightener of the present invention can be used in papermaking. Preferably during wet manufacturing processes.

[00141] FWA or optical brightener of the present invention can be used in paper finishing.

[00142] The FWA or optical brightener of the present invention can be used to treat cellulose fiber before papermaking.

[00143] Cosmetics

[00144] FWA or optical brightener of the present invention can be used in conjunction with emollient to provide cosmetic compositions.

[00145] FWA or optical brightener of the present invention can be used to produce sunscreen compositions.

[00146] The advantage of FWA cosmetics or optical brighteners is that they provide an increase in the apparent brightness, shine or color intensity of cosmetics and do so in an environmentally acceptable format. Examples

[00147] Example 1 - Evaluation of fluorescent bleaching agents

[00148] The fluorescent whitening and optical brightening agents of the present invention were evaluated for chemical and UV stability, quantum yield, fluorescence / whitening effect, biodegradability, and substantivity on cellulose compared to commercial references.

[00149] Relative quantum yield

[00150] A solution of FWA was prepared in 0.1M sodium carbonate. The solution was diluted until a UV absorbance of 0.1 was measured (Agilent™ Cary UV-vis), this was then further diluted to provide a range of UV absorbance readings. These solutions were then used to measure the fluorescence response (Agilent™ Cary Eclipse fluorescence spectrometer). The integrated area of ​​the fluorescence measurement was plotted against the UV absorbance readings. This was compared with the gradient measurement for a quinine sulfate in 0.1M sulfuric acid standard to calculate the quantum yield. Petition 870250079624, dated 05 / 09 / 2025, pages 681 / 725 45 / 67 relative. The results are provided below in Tables 1 and 2. Table 1: Relative quantum yield of the reference FWA or optical brightener. Structure Maximum emission (nm) Relative quantum yield OH 1 ϊ η i HN : SO3Na YY¥ HO J ,·: N.< NL > NNY OH . / : / ÂJ SOsNa HN. NNN ' ó XY 1 HH 1 η OH Reference 2 (DAS-2) CAS 16470-24-9 430.9 33% NaO3S^\ SO3Na Reference 4 (DSBP) CAS 27344-41-8 429.8 78% Table 2: Relative quantum yield of FWA or examples of optical brighteners Structure Maximum emission (nm) Relative quantum yield O^OH jX O^N^s OH 417.0 72% Petition 870250079624, dated 05 / 09 / 2025, pp. 682 / 725 46 / 67 jX O^N^s 0= / s__ / 0 / O^° 419.8 77% Hr o 418.9 45% / oo $ / % o 417.8 71% H 0 , ,N, V nh2 H2N^y^NH2 NH Xi °^X? Petition 870250079624, dated 05 / 09 / 2025, pp. 683 / 725 47 / 67

[00151] The relative quantum yields of the compounds according to the invention can easily be considered comparable to or superior to the standards of the prior art. Fluorescence / whiteness effect measured in cellulose powder:

[00152] Color measurement was performed using a Lovibond® LC100 spectrocolorimeter. The surface color of the powder was quantified using a series of L*, a*, and b* values ​​from the CIELAB color model defined by the International Commission on Illumination (Commission Internationale de l'Eclairage). L* is a measure of the amount of white or black in a sample; higher L* values ​​indicate a lighter color sample. A measure of the amount of red or green in a sample was determined by a* values. A measure of the amount of blue or yellow in a sample was determined by b* values; lower (more negative) b* values ​​indicate more blue in a sample. Color can also be measured using a different model, CIE L*C*h*, where C* represents chromaticity and h* represents the hue angle. The powder from each substantivity test was measured relative to washed cellulose and defined the starting point for the next UV stability test.The results are presented below in Table 3. Table 3: Results, for example, compounds Sample L* a* (-ve green +ve red) b* (-ve blue +ve yellow) C* h* (0 = red 90 = yellow 180 = green 270 = blue) Blank 94.8 0.6 2.2 2.3 75.4 ω 1 97.6 0.2 2.3 2.3 83.9 Petition 870250079624, dated 05 / 09 / 2025, pages 684 / 725 48 / 67 OOO O^N^S Os / γO 7O / O 98.4 0.1 2.2 2.2 86.6 / oo $ / % Rp o 97.7 0.4 1.8 1.9 77.4 HV nh2 O^N^s hRnh; 97.7 0.2 2.5 2.5 84.6 CM wo 99.6 -0.3 0.9 1 109.6 M 0 °γΝγ\<Η2 98.4 0.1 1.6 1.6 87.7 O 0 Η2Ν^Υ^ΝΗ2 O^NH XI 98.8 0.2 1.1 1.1 80.8

[00153] All compounds exhibit a substantial change to a blue hue (h* = 270) compared to white, demonstrating effectiveness in terms of substantivity and optical effect. UV stability (i.e., resistance to light)

[00154] The cellulose powder prepared above was exposed to UV rays in a UV box under a 4W lamp (365 nm) for a period of 3 months. The samples were then visually inspected, photos were taken, and measurements were taken. Petition 870250079624, dated 05 / 09 / 2025, pages 685 / 725 49 / 67 colors were re-evaluated to monitor the loss of whiteness and changes from blue to yellow or darker shades. The results are presented below in Table 4. Table 4: Results, for example, compounds after UV exposure. Sample L* a* (-ve green +ve red) b* (-ve blue +ve yellow) C* h* (0 = red 90 = yellow 180 = green 270 = blue) O^OH O^N^s Oγ OH 99.6 0.2 2.6 2.7 85.6 / O ooso 97.4 0.7 4 4 80.1 o C> p 95.6 0.6 2.4 2.4 75 H O. ,NY nh2 O^N^s θ-Ζ HN^NH2 97.6 0.2 3.2 3.2 85.8 Petition 870250079624, dated 05 / 09 / 2025, pages 686 / 725 50 / 67 HY nh2 97.4 0.4 2.3 2.3 79.3 u 0 °γΝγ^ΝΗ2

[00155] The FWAs of the present invention are stable under UV under the test conditions. Chemical stability

[00156] FWA or optical brightener was weighed at 0.0100 - 0.0200 g in a 100 mL volumetric flask and made up to volume using deionized water. The solution was sonicated for 5 minutes to ensure the creation of a uniform dispersion. The solution was divided into five 10 mL samples. Sample 1 was a blank with 0.2 mL of DI water added. For sample 2, 0.1 mL of 1M sodium hydroxide solution and 0.1 mL of DI water were added; for sample 3, 0.1 mL of 1M sodium bicarbonate solution and 0.1 mL of DI water were added; for sample 4, 0.1 mL of 1M sodium hydroxide solution and 0.1 mL of 0.75M hydrogen peroxide were added; for sample 5, 0.1 mL of 1M sodium carbonate solution and 0.1 mL of 0.75M hydrogen peroxide were added. All samples were heated to 40°C for 48 hours and then analyzed by HPLC. The blank sample is used to identify the retention time of the FWA or optical brightener and the maximum response.Any hydrolysis and oxidation of the FWA or optical brightener would result in the appearance of new compound(s) in the chromatogram. Petition 870250079624, dated 05 / 09 / 2025, pp. 687 / 725 51 / 67 different retention times, along with a reduction in the response of the FWA or optical brightener. The other samples are reported as FWA or % optical brightener response versus white. Conditions 3 (carbonate) and 5 (carbonate and hydrogen peroxide) are the most relevant for laundry applications (e.g., heavy-duty laundry detergent). The results are shown below in Table 5. Table 5: Chemical stability of compounds from the examples Structures Condition 3 (% response vs. blank) Condition 5 (% response vs. blank) Comment O^OH O^N^s ° Λ OH 100 99.8 Excellent stability o^nh20^Nys nh2 86 86.7 Good stability, limited partial saponification of one of the amide groups.

[00157] Monitoring the chemical stability of the FWAs presented in Table 5 confirms the excellent stability of the non-functionalized structures and the structures functionalized with amines in the presence of high pH and oxidants. These results demonstrate a high degree of compatibility with laundry applications.

[00158] The fluorescent bleaching agents of the present invention were evaluated for biodegradability and substantivity in cellulose in comparison with commercial references. Substantivity to cellulose: Petition 870250079624, dated 05 / 09 / 2025, pages 688 / 725 52 / 67

[00159] A buffer solution was prepared by weighing 0.10 g of SDS, 1.0 g of glycerol, 8.4 g of sodium carbonate, 1.7 g of sodium bicarbonate, and 0.4 g of ethylenediaminetetraacetic acid (EDTA) into a 50 mL beaker and transferring it to a 2000 mL beaker. The 50 mL beaker was rinsed in the 2000 mL beaker using tap water and made up to approximately 1 L using tap water while stirring until completely dissolved. This solution was transferred to a 2 L volumetric flask and made up to volume with tap water.

[00160] The FWA was weighed to 0.0100 - 0.0200 g in a 100 mL volumetric flask and made up to volume using buffer solution. The solution was sonicated for 5 minutes to ensure the creation of a uniform dispersion.

[00161] In a 250 mL beaker, 10 g of Thermo Scientific™ 50 μm microcrystalline cellulose powder and 50±1 g of FWA solution were added and their exact weight was recorded. The cellulose / FWA paste was stirred for 20 minutes before being filtered in a filtration unit with a polypropylene filter cloth. The filtrate (mother liquor) was collected. The cellulose was rinsed three times with 50 mL of tap water, the cellulose was re-entrained by simple stirring before being filtered. Combined filtrates (mother liquor and rinses 1 to 3) were collected and weighed. The cellulose cake was removed from the filtration unit and dried in a vacuum oven at 35°C for subsequent visual, fluorescence, and lightfastness testing.

[00162] To measure the amount of FWA retained in the cellulose, the initial sample and the combined filtrates were run by HPLC. Using the peak areas for the FWA and input-output weights, the amount of FWA retained can be calculated. The results are presented below in Tables 6 and 7.

[00163] Substantivity can be defined by the following criteria: poor (<25%), moderate (25-50%), good (50-85%) and excellent (>85%). Petition 870250079624, dated 05 / 09 / 2025, pages 689 / 725 53 / 67 Table 6: Substantivity of the compounds in cellulose of the reference compounds No. Structures Substantivity (% in cellulose) Substantivity (excellent, good, moderate, poor) 1 Π Η r? so,n. rrNYVJ Λ AXV ύ r .VA so* ηβά OHU Reference 1 (DAS-1) CAS 16090-02-1 98% Excellent 2 OH ,^\_^,SO3Na Γ ¥ h 1 HN SO3Na AA ffl HO. X / LJ N.^NL > n'n fi OH SO3N3 HN ·- NNN η ih |l Ί SO3Na OH Referência 2 (DAS-2) CAS 16470-24-9 98% Excelente 3 OH Al h NH SOjNa NNN % Λ |ΤγΑγ A Ah ΑΛΛΆ HN^ HU OH Referência 3 (FB28) CAS 4193-55-9 98% Excellent 4 N 8O3S ΘΟβΝθ Reference 4 (DSBP) CAS 27344-41-8 93% Excellent Petition 870250079624, dated 05 / 09 / 2025, pp. 690 / 725 54 / 67 Table 7: Substantivity of compounds in cellulose from the examples Structures Substantivity (% in cellulose) Substantivity (excellent, good, moderate, poor) O ° ' - 97% Excellent / o X os ° 75% Good 0^y 77% Good HO / N . y nh2 52% Good M 0 VA« fil 0H °ô 61% Good H r0H °yN^0H 0H0 Xs 34% Moderate Petition 870250079624, dated 05 / 09 / 2025, pp. 691 / 725 55 / 67 CM 27% Moderate

[00164] The compounds presented in Table 7 exhibit performance levels (with respect to substantivity) that approach comparability with the industry standards presented in Table 6, in addition to being non-toxic. Furthermore, these compounds are biodegradable, non-bioaccumulative, and can be produced from sustainable materials. Substantivity in the fabric:

[00165] 10L of tap water were added to the washing machine at 35°C. Fabric clocks (10 cm x 10 cm, supplier: CFT, Center for Testmaterial BV) were added to the water, along with 20 g of ECE-2 ISO 105 C-08 dye transfer test detergent and 0.1 g of FWA. The washing machine was run for 9 minutes and then allowed to drain completely.

[00166] 5L of cold water were added to rinse the fabric and the washing machine ran for 3 minutes before being drained, and then the fabric was subjected to a second rinse with 5L of cold water in a 3-minute run. After rinsing, the fabric samples were dried for 3 minutes before being fully air-dried.

[00167] The surface color of the samples was measured in duplicate using a Lovibond® LC100 spectrocolorimeter. The average values ​​for surface color are given below in Table 8. Table 8: Substantivity of compounds in tissue, for example, compounds Structures h* (0 = red 90 = yellow 180 = green 270 = blue) PCN01 (polyester / cotton 65 / 35, fabric, CN17 (cotton, cretonne, CN11 (cotton, cretonne, Petition 870250079624, dated 05 / 09 / 2025, pages 692 / 725 56 / 67 180 g / m2) bleached, mercerized, 155 g / m2) bleached, 155 g / m2) Blank 165.9 128.8 152.3 OH, ,OH JX OH 192.4 209.9 188.3 0..,.0 / . XI O;ÍN S0 Λ ,__yO / 0^° 195,5 160,9 195,2 ,ο,χχΐ XX O^N^s °x 228,3 176,5 182,9 / oos / % o 175,1 188,8 158,6 OI TZ / OI < T \ z / / SJ o ° 194.4 197.3 217.1 HV nh2 JX ° L_JS 217.8 230.6 202.2 Petition 870250079624, dated 05 / 09 / 2025, pp. 693 / 725 57 / 67 O 0 H2X'X Ox / NH ​​​​XI 0 o 198.5 198.3 214.0

[00168] All compounds show a substantial change to a blue hue (h* = 270) compared to white, demonstrating effectiveness in terms of substantivity and optical effect.

[00169] Example 2 - Biodegradability assessment using Biowin™

[00170] The chemical structures of the present invention are biodegradable.

[00171] For the purposes of this invention:

[00172] An inherently biodegradable fluorescent brightening agent is defined as > 20% but < 60% biodegradability in water, as measured by OECD test 301A-F.

[00173] A readily biodegradable fluorescent bleaching agent is defined as the ability of a product to biodegrade rapidly and completely in water (>70% removal of dissolved organic carbon, >60% theoretical carbon dioxide, or >60% theoretical oxygen demand, depending on OECD test methods 301A-F) within a 10-day window in 28 days.

[00174] The Biowin™ software was used to provide biodegradability predictions. This biodegradability prediction method is available as part of the Estimation Program Interface (EPI) software package provided by the United States Environmental Protection Agency (EPA). Environ. Sci. Technol., 1994, 28, 459-465, shows an example of the group contribution method for predicting the probability and rate of aerobic biodegradation. This is the type of method used by Biowin™.

[00175] The Biowin 3 and Biowin 5 models are of particular relevance to the present invention. The predicted biodegradability of some of the compounds according to the present invention was evaluated using these models. If the result of Biowin 3 (final research model) is >= 2.75 (i.e., weeks) Petition 870250079624, dated 05 / 09 / 2025, pages 694 / 725 If the probability of the Biowin 5 (MITI linear model) is >= 0.5, the prediction is YES (readily biodegradable). If this condition is not met, the prediction is NO (not readily biodegradable). The results are presented below in Tables 9 and 10: Table 9: Biowin's predicted biodegradability score for reference compounds Reference structures Biowin 3 Biowin 5 Interpretation of Biowin 3 & 5 prediction. D η r? SO3Na ^ rNrN.r A γ SOsNa HNr·- OHU Reference 1 (DAS-1) CAS 16090-02-1 0.0223 -2.1266 Very poor based on Biowin criteria. Experimentally confirmed as neither easily nor inherently biodegradable, see ECHA (https: / / echa.europa.eu / registrationdossier / - / registereddossier / 14744 / 5 / 3 / 1) OH ^\,5O3N3 1 lí hi HN SO3Na XX ΐ T HO Jx à / Y Jl N ,; N k > NN γ OH SOjNa HN^. 1 H h Ί H '' SO: OH Reference 2 (DAS-2) CAS 16470-24-9 0.8228 -1.3985 Very poor, meets Biowin 3 and Biowin 5 criteria for immediate biodegradability by a large margin. Experimentally confirmed as neither readily nor inherently biodegradable, see ECHA (https: / / echa.europa.eu / registrationdossier / - / registereddossier / 16029 / 5 / 3 / 2) Petition 870250079624, dated 05 / 09 / 2025, pp. 695 / 725 59 / 67 OH SO3Na kOrNYNYNy 1 1 HI HO. AX N.^N k > N^N OH L / k Jk JL 0 SO3Na HN / . NN 3 lí H OH Reference 3 (FB28) CAS 4193-55-9 0.5999 -1.3547 Very poor, meets Biowin 3 and Biowin 5 criteria for immediate biodegradability by a large margin. Experimentally confirmed as neither easily nor inherently biodegradable, see ECHA (https: / / echa.europa.eu / registrationdossier / - / registereddossier / 15216 / 5 / 3 / 2) NaO3S.^ SO3Na Reference 4 (DSBP) CAS 27344-41-8 2.3375 -0.6302 Poor to average, fails Biowin 3 and Biowin 5 criteria for immediate biodegradability. However, scores significantly better than above other references. Experimentally confirmed as moderately removed from water (0% DOC removal in 28 days with OECD method 301A and 43.7% DOC removal with OECD method 302B), see ECHA (https: / / echa.europa.eu / registration- Petition 870250079624, dated 05 / 09 / 2025, pp. 696 / 725 60 / 67 dossier / - / registereddossier / 13511 / 5 / 3 / 2) Table 10: Biowin's predicted biodegradability score for structures within this invention. Biowin 3 Structures Biowin 5 Interpretation of Biowin 3 & 5 prediction. O^OH O^N^SO / OH 3.3411 0.5280 Easily biodegradable according to Biowin criteria ' b 2.5380 0.2877 Expected to be moderately biodegradable according to Biowin criteria: Biowin 3 score is within the range of 2.25-2.75 (weeks to months), Biowin 5 score is significantly better than either of the references. xo ξ o W $ oo / 2.4062 0.6475 Expected to be biodegradable according to Biowin criteria: Biowin 3 score is within the range of 2.25-2.75 (weeks to months), Biowin 5 score is above the limit. ΟγO^o^O. xl Q^N^JS 2,6063 0,5448 Expected to be biodegradable according to Biowin criteria: Biowin score 3 is within the range of 2.25-2.75 (weeks to months), Biowin score 5 is above the limit. Petition 870250079624, dated 05 / 09 / 2025, pp. 697 / 725 61 / 67 H V nh2 °O 2.5864 0.4374 Expected to be biodegradable according to Biowin criteria: Biowin score 3 is within the range of 2.25-2.75 (weeks to months), Biowin score 5 is close to the limit and significantly higher than either of the references. oo Vo xa 2.9871 0.5125 Easily biodegradable according to Biowin criteria. H r0H °Ti 0H Γιΐ 0H 2.6948 0.8230 Easily biodegradable according to Biowin criteria. J Qv bo 2.8303 0.7135 Easily biodegradable according to Biowin criteria. o °w ω 2.5078 0.2767 It is expected to be biodegradable according to Biowin criteria: Biowin 3 score is within the range of 2.25-2.75 (weeks to months), Biowin 5 score is close to the limit and significantly higher than either of the references. Petition 870250079624, dated 05 / 09 / 2025, pp. 698 / 725 62 / 67 CN °Z / Ζί O 2.4458 0.2984 Expected to be biodegradable according to Biowin criteria: Biowin 3 score is within the range of 2.25-2.75 (weeks to months), Biowin 5 score is close to the limit and significantly higher than either of the benchmarks. O 0 H2N^XnH2 O^NH ° O 2.3275 0.3383 Expected to be biodegradable Biowin 3 score is within the range of 2.25-2.75 (weeks to months), Biowin 5 score is close to the limit and significantly higher than either of the benchmarks. [moderate to good]

[00176] Example 3 - Thermogravimetric analysis (TGA)

[00177] The samples were analyzed using thermogravimetric analysis with Mettler Toledo TGA\DSC3+ on a temperature ramp from room temperature up to 800°C under airflow. Table 11: Thermogravimetric analysis of reference compounds Structure Stability (less than 2% mass loss) up to temperature (°C) Mass loss at 150 °C OH ^\,SO3Na 1 Ϊ H 1 HN SO3Na p X ÍTl HO. Z Z. .^.ZsZ N,.N L. > NN ZZ Z 0H ^mZmZmZZ SOsNa HN - NNN η z SO3Na OH Reference 2 (DAS-2) 79.5 7.5% Petition 870250079624, dated 05 / 09 / 2025, pp. 699 / 725 63 / 67 CAS 16470-24-9 NaO3S..^. XX SO3Na Reference 4 (DSBP) CAS 27344-41-8 78.8 7.1% Table 12: Thermogravimetric analysis of compounds from the examples Structure Stability (less than 2% mass loss) up to temperature (°C) Mass loss at 150 °C Ο^,ΟΗ Xi O^N^s OH 250.0 0.1 °y°'^ Χι O^N^s °Λ __ / O / O^° 129.9 3.8% ObvX b 155.2 1.9% Petition 870250079624, dated 05 / 09 / 2025, pp. 700 / 725 64 / 67 ° 107.3 6.6% CXI XX / CM < X \

[00178] Part of the mass loss at low temperature can be attributed to the loss of residual moisture. Even so, most of the compounds of the present invention can be considered stable up to 110°C. They also exhibit comparable mass loss at 150°C relative to reference standards, therefore at least a similar degree of thermostability.

[00179] The thermal stability of the fluorescent whitening and optical brightening agents of the invention is important because, in the case of laundry powder detergent, the ingredient may be introduced before the water removal phase in a fluidized bed dryer, where temperatures can reach 50-110°C.

[00180] Example 4 - Detergency Petition 870250079624, dated 05 / 09 / 2025, pp. 701 / 725 65 / 67

[00181] Representative detergent compositions of the present invention are described in Tables 13, 14, 15 and 16. Table 13: Representative compositions of powdered soap for conventional and compact compositions All values ​​are % by weight. Ingredients Conventional Compact Anionic and non-ionic 8-15 10-30 Surfactants Builders 20-50 20-40 Co-builders 1-5 1-7 Bleaching agents 10-25 10-20 Bleach activators 1-3 2-8 Anti-redeposition agents 1 1 Corrosion inhibitors 2-6 2-6 Bleach stabilizers 0-1 0-1 Foam regulators 0.1-1 0.1-2.0 Enzymes 0.3-1.0 0.5-2.0 FWA or optical brightener 0.1-0.5 0.1-0.5 Minor, water equilibrium at 100% Apparent density, g / L 500-650 600-900 Table 14: Representative detergent tablet compositions for zeolite and phosphate-based compositions All values ​​are % by weight. Ingredients Zeolite base, % Phosphate base, % Surfactants 13-18 15-18 Bleaching agents 13-15 12-16 TAED 3-7 4-7 Zeolite 1 15-30 Sodium triphosphate 25-45 Petition 870250079624, dated 05 / 09 / 2025, pages 702 / 725 66 / 67 Layered silicate 0-9 0-9 Sodium polycarboxylate 2-3 2 Disintegrants 5-17 0-12 Enzymes 2-4 2-3 FWA or optical brightener 0.1-0.5 0.1-0.5 Minor, water equilibrium at 100% Table 15: Representative compositions of powdered soap for homogeneous and structured compositions All values ​​are % by weight. Structured Homogeneous Ingredient Anionic surfactants 7-18 10-25 Non-ionic surfactants 15-30 6-10 Soaps 10-25 4-8 Builders 0-5 15-30 Solubilizers 0-12 0-5 Alcohols 5-12 0-5 Enzymes 0-2.5 0-1.5 FWA or optical brightener 0.05-1.0 0.05-1.0 Smaller amounts, water balance to 100% Table 16: Representative compositions of fabric bleaching detergents for solid and liquid forms All values ​​are % by weight. Ingredient Powder Liquid Anionic surfactants 5-15 2-10 Non-ionic surfactants 0-1 3-5 Builders 60-75 Bleach 3-15 3-4 Petition 870250079624, dated 05 / 09 / 2025, pages 703 / 725 67 / 67 Filler 5-20 FWA or optical brightener 0.2-1.0 0.1-1.0 Enzymes 0-1 Minor, water balance to 100% Petition 870250079624, dated 05 / 09 / 2025, pages 704 / 725< / z>

Claims

1 / 10 Claims 1. USE of compounds of formula (I) as fluorescent bleaching agents or optical brighteners in a laundry application, characterized in that the compounds of formula (I) have the structure: 0 NYx A (I) wherein: A is CHR1R2(CH2)n wherein R1 is H, CH2OH or CO2, R2 is H or CH2OH and wherein n is 1 or 2, or wherein A is an optionally substituted aromatic or heteroaromatic ring fused with N and X wherein N and X are respectively bonded to adjacent carbon atoms in the ring; X is O, S or NH; Y is Z or X'L; o or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, wherein M is selected from an alkali metal or an alkaline earth metal;R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units, or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; R4 is independently selected from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl, or dicarbamoylmethyl; alternatively, NR42 represents a heterocyclic ring (such as morpholine); and Petition 870250079624, dated 05 / 09 / 2025, page 716 / 725 2 / 10 wherein Y is X'L; X' is O, S or NH; and L represents a bonding portion connecting m repeating units of formula (I) having X' as defined above in place of Y; 2. USE of the compounds of formula (II) as fluorescent brighteners or optical brighteners in a laundry application, characterized in that the compounds of formula (II) have the structure: wherein Y is Z or X'L; Z is OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, M represents an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alcoholic polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; R4 is selected independently from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl;Alternatively, NR42 represents a heterocyclic ring (such as morpholine); and R is H, CHR5R6, R5, R6, an alkyl sulfonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) where each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2 Petition 870250079624, dated 05 / 09 / 2025, p. 717 / 725 3 / 10 hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl or cyano, optionally where R5 and R6 are the same or different, en is 1 or 2; where when Y is X'L; X' is O, S or NH; and L represents a linker portion connecting m repeating units of a variant of formula (II) in which X', as defined above, is present in place of Y; 3. USE of compounds of formula (I) according to claim 1 or of compounds of formula (II) according to claim 2, characterized in that: a. where R3 represents a linear or branched alkyl, R3 is preferably selected from methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl or 2-ethylhexyl; b. where R3 represents an alkyl alcohol, R3 is selected from methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, dodecanol or stearyl or oleyl alcohol; c. where R3 represents an aryl, R3 is phenyl; d. where R3 represents an alkaryl, R3 is selected from benzyl or ethylphenyl; e. where R3 represents a linear or branched alkyl alcohol, R3 is selected from 4-hydroxybutyl; f. where R3 represents a linear or branched alcohol polyol, R3 is a diol or triol, optionally 2,3-dihydroxypropyl, or 2-hydroxy-1-(hydroxymethyl)ethyl; g.where R3 represents a hydroxyalkylamine, R3 is selected from triethanolamine, N-methyldiethanolamine or triisopropanolamine; h. where R3 represents a polyhydric alcohol, R3 is glycerol; Petition 870250079624, dated 05 / 09 / 2025, page 718 / 725 4 / 10 i. where R3 represents a sugar, R3 is selected from dextrose, fructose, galactose, glucose, lactose, maltose or sucrose; j. where R3 represents a linear or branched alkyl ether, R3 is selected from 2-(2-hydroxyethoxy)ethyl, 2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 2-[2-(2-hydroxy-1-methylethoxy)-1-methylethyl, 3-(3-hydroxypropoxy)propyl, 3-[3-(3-hydroxypropoxy)propoxy]propyl, 4-(4-hydroxybutoxy)butyl, 4-[4-(4-hydroxybutoxy)butoxy]butyl, 2-(2-methoxyethoxy)ethyl, or 2-[2-(2-methoxyethoxy)ethoxy]ethyl; and / or k. where R3 represents a polyester or polyoxyalkylene chain having from 2 to 1000 repeating units, the chain is a homopolymer or a copolymer.

4. USE of fluorescent brightening agent or optical brightening compounds, according to any one of claims 1 to 3, characterized in that: a. the ligand L is derived from an alcohol and X' is the oxygen of the precursor alcohol; or b. the ligand L is derived from an amine and X' is the nitrogen of the precursor amine.

5. USE of fluorescent brightening agent or optical brightening compounds, according to any one of claims 1 to 4, characterized in that it is a dimeric or oligomeric compound wherein m is 2 or more, optionally 3 to 20, optionally 3.

6. USE of a fluorescent brightening agent or optical brightening compounds, according to any one of claims 1 to 5, characterized in that the binder L consists of any of the C4 to C12 ethylenes, propylenes or alkylenes, a polyester chain with 0 to 1000 repeating units being a homopolymer or copolymer, or a polyoxyalkylene chain with 0 to about 1000 repeating units being a homopolymer or copolymer, triethanolamine, glycerol or sugar. Petition 870250079624, dated 05 / 09 / 2025, p. 719 / 725 5 / 10 7. USE of fluorescent brightening agent or optical brightening compounds, according to any one of claims 1 to 6, characterized in that the compounds are formulated for use as fluorescent brightening agents or optical brighteners.

8. USE of fluorescent brightening agent or optical brightening compounds, according to claim 7, characterized in that the compounds comprise part of a fluorescent brightening or optical brightening formulation, wherein the formulation further comprises at least one auxiliary compound, optionally selected from one or more surfactant(s), detergent(s), bleach(s), carrier compound(s), stabilizer(s) and / or dispersant(s).

9. A fluorescent bleaching or optical brightening formulation for laundry, characterized in that it comprises a fluorescent bleaching agent or an optical brightening compound of formula (I) and at least one detergent, bleach, carrier compound, stabilizer and / or dispersant; wherein the compound of formula (I) has the structure: 0 Vx A (I) wherein: A is CHR1R2(CH2)n wherein R1 is H, CH2OH or CO2, R2 is H or CH2OH and wheren is 1 or 2, or wherein A is an optionally substituted aromatic or heteroaromatic ring fused with N and X where N and X are respectively bonded to adjacent carbon atoms in the ring; X is O, S or NH; Y is Z or X'L; or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, where Petition 870250079624, dated 05 / 09 / 2025, p.720 / 725 6 / 10 M is selected from an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; R4 is independently selected from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; Alternatively, NR42 represents a heterocyclic ring (like morpholine); and wherein Y is X'L; X' is O, S, or NH; and L represents a linking moiety connecting m repeating units of formula (I) having X' as defined above in place of Y.

10. Fluorescent bleaching or optical brightening formulation for laundry, characterized in that it comprises a fluorescent bleaching agent or an optical brightening compound of formula (II) and at least one detergent, bleach, carrier compound, stabilizer and / or dispersant; wherein the compound of formula (II) has the structure: where Y is Z or X'L; Z is OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, Petition 870250079624, dated 05 / 09 / 2025, p. 721 / 725 7 / 10 M represents an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alcoholic polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units, or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5;R4 is selected independently from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; alternatively, NR42 represents a heterocyclic ring (such as morpholine); and R is H, CHR5R6, R5, R6, an alkyl sulfonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) wherein each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl or cyano, optionally wherein R5 and R6 are the same or different, and en is 1 or 2; wherein when Y is X'L; X' is O, S or NH; and L represents a ligand moiety connecting m repeating units of a variant of formula (II) in which X', as defined above, is present in place of Y; 11. METHOD for providing fluorescent brightening or optical brightening to a laundry substrate, characterized in that it comprises contacting the laundry substrate with a fluorescent brightening agent or optical brightening compound of formula (I) or a fluorescent brightening or optical brightening formulation, as defined in claim 9, under conditions effective to permit chemical and / or physical bonding of the fluorescent brightening agent or optical brightener on or within the substrate; wherein the compound of formula (I) has the structure: Y\ / >o χι 0 <?x A (I) em que: A é CHR1R2(CH2)n em que R1 é H, CH2OH ou COZ, R2 é H ou CH2OH e em que n é 1 ou 2, ou em que A é um anel aromático ou heteroaromático opcionalmente substituído fundido com N e X em que N e X estão respectivamente ligados a átomos de carbono adjacentes no anel; X é O, S ou N-H; Y é Z ou X'L;o or each Z is independently OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, wherein M is selected from an alkali metal or an alkaline earth metal; R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alkyl polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; R4 is selected independently from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; alternatively, NR42 represents a heterocyclic ring (such as morpholine); and wherein Y is X'L; X' is O, S or NH;and L represents a linking portion that connects m repeating units of formula (I) having X' as defined above in place of Y.; 12. METHOD for providing fluorescent brightening or optical brightening to a laundry substrate, characterized in that it comprises contacting the laundry substrate with a fluorescent brightening agent or optical brightening compound of formula (II) or a fluorescent brightening or optical brightening formulation, as defined in claim 10, under conditions effective to allow chemical and / or physical bonding of the fluorescent brightening agent or optical brightener on or within the substrate; wherein the compound of formula (II) has the structure: wherein Y is Z or X'L; Z is OH, OM, OR3, O(CH2)qSO3M, NH2, NHOH, NHR4 or NR42, M represents an alkali metal or an alkaline earth metal;R3 represents a linear or branched alkyl, an aryl, an alkaryl, an aralkyl, a linear or branched alkyl alcohol, a linear or branched alcoholic polyol, a hydroxyalkylamine, a polyhydric alcohol, a sugar, a linear or branched alkyl ether, a polyester with 2 to 1000 repeating units or a polyoxyalkylene chain with 2 to 1000 repeating units; q is from 1 to 5; Petition 870250079624, dated 05 / 09 / 2025, page. 724 / 725 10 / 10 R4 is independently selected from methyl, ethyl, propyl, C4 to C12 alkyl, benzyl, 2-hydroxyethyl, 1-hydroxy-2-propanyl, 1,3-dihydroxy-2-propanyl, 2,3-dihydroxypropyl, cyanomethyl, 2-aminoethyl or dicarbamoylmethyl; alternatively, NR42 represents a heterocyclic ring (such as morpholine);and R is H, CHR5R6, R5, R6, an alkyl sulfonate, a polyether, CH2COZ or CH(COZ)((CH)nCOZ) where each Z may be the same or different, R5 and R6 independently represent hydrogen, alkyl (such as methyl, ethyl, propyl, isopropyl), vinyl, phenyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1,2-dihydroxyethyl, aminomethyl, (dimethylamino)methyl, 5-aminopentyl or cyano, optionally where R5 and R6 are the same or different, en is 1 or 2; where Y is X'L; X' is O, S or NH; and L represents a ligand moiety connecting m repeating units of a variant of formula (II) in which X', as defined above, is present in place of Y Petition 870250079624, dated 05 / 09 / 2025, p. 725 / 725;