KR20070018979A - Optical brighteners for ink jet printing substrates - Google Patents

Abstract

The present invention

Fluorescent brightener of Formula 1 or mixtures thereof (a),

Cationic polymer (b),

Water (c) and

A composition for fluorescence brightening of a substrate suitable for inkjet printing, optionally comprising at least one pigment and / or at least one additional adjuvant (d), a method of using the composition and a substrate thus treated.

Formula 1

In Formula 1 above,

X ₁ , X ₂ , X ₃ and X ₄ are each independently of each other —NR ₁ R ₂ or —OR ₃ ,

R ₁ and R ₂ independently of one another are hydrogen, cyano, C ₁ -C ₄ alkyl group wherein the alkyl group is C ₁ -C ₄ alkoxy, hydroxy, carboxyl or salt thereof (-C0 ₂ M), cya Furnace, carboxamido, thiol, guanidine, substituted or unsubstituted phenyl, unsubstituted or C ₁ -C ₄ alkyl-substituted C ₅ -C ₈ cycloalkyl, halogen, heterocycle and sulfonic acid residues Is substituted or unsubstituted with one or two residues selected, and the carbon chain of an alkyl group having 2, 3 or 4 carbon atoms may be interrupted by oxygen) or a C ₅ -C ₇ cycloalkyl group, or

R ₁ and R ₂ together with the nitrogen atom connecting them form a 5- or 6-membered heterocyclic ring,

R ₃ is C ₁ -C ₄ alkyl,

M is ammonium mono-, di-, tri-, or tetra-substituted with H, Na, Li, K, Ca, Mg, ammonium, or C ₁ -C ₄ alkyl and / or C ₂ -C ₄ hydroxyalkyl.

Inkjet printing, substrate, fluorescent brightener, printability, whiteness.

Description

Optical brighteners for ink jet printing substrates

The present invention relates to a composition suitable for fluorescence brightening of a substrate suitable for inkjet printing.

In recent years, inkjet recording methods are rapidly being widely used in the printing field due to advantages such as low cost, relatively high speed, low noise and easy production of multicolor images on substrates such as paper and foil.

However, for example, plain paper used for ordinary photo printing is very poor in ink absorption, and when used as an inkjet substrate, the ink remains on the surface of the paper for a considerable time, causing stains and smears. . Dyes commonly used in inkjet printing belong to water soluble anionic direct dyes or disperse dyes, which are dispersed by anions. In order to fix these dyes to the substrate to obtain high resolution and good ink absorption, the substrates are typically treated with a cationic polymer that acts as a fixative for the anionic dye formulation.

Conventional Fluorescent Whitening Agents (FWAs) are generally derivatives of 4,4'-bis (triazinylaminostilbene) -2,2'-disulfonic acid, wherein the triazine ring is anilino or a substituent thereof. Monosulfonic acid or disulfonic acid groups), which exhibits somewhat poor whitening efficacy in the presence of cationic polymers, and the whitened substrates also have poor printability due to partial neutralization of the effect of the polymer in the presence of such anionic FWA. Do.

One attempt to solve this problem is described in US Pat. No. 4,620,197, which uses cationic FWA instead of conventional anionic FWA. However, these compounds are in principle less readily available and therefore more expensive than anionic homologues or commercially available products and are therefore not suitable for whitening substrates such as paper and foil.

A combination of FWA derived from 4,4'-bis (triazinylaminostilbene) -2,2'-disulfonic acid with pigments useful as fillers for seed pulp and coating is described in British Patent 2,284,829. However, in this case, preferably, conventional FWA-containing aniline substituents are incorporated in the water-insoluble urea-formaldehyde resin, resulting in a fluorescent pigment.

A method of increasing the whiteness of lignin-containing pulp, including the addition of conventional FWA to the pulp during pulp production, is described in EP899,373, but the negative effect of the addition of cationic starch, optionally present as an additive Is not considered or mentioned.

Surprisingly, by the present invention, by using a specific FWA derived from 4,4'-bis (triazinylaminostilbene) -2,2'-disulfonic acid but lacking the conventional aniline or aniline sulfonic acid substituents, Excellent whiteness can be achieved even in the presence of the polymeric polymer, so that the whitened substrate has been found to exhibit excellent inkjet recording properties.

As a result, the present invention

Fluorescent brightener of Formula 1 or mixtures thereof (a),

Cationic polymer (b),

Water (c) and

And optionally, one or more pigments and / or one or more additional adjuvants (d).

In Formula 1 above,

X ₁ , X ₂ , X ₃ and X ₄ are each independently of each other —NR ₁ R ₂ or —OR ₃ ,

R ₁ and R ₂ independently of one another are hydrogen, cyano, C ₁ -C ₄ alkyl group wherein the alkyl group is C ₁ -C ₄ alkoxy, hydroxy, carboxyl or salt thereof (-C0 ₂ M), cya Furnace, carboxamido, thiol, guanidine, substituted or unsubstituted phenyl, unsubstituted or C ₁ -C ₄ alkyl-substituted C ₅ -C ₈ cycloalkyl, halogen, heterocycle and sulfonic acid residues selected from the group consisting of Is substituted or unsubstituted with one or two moieties and the carbon chain of an alkyl group having 2, 3 or 4 carbon atoms may be interrupted by oxygen) or a C ₅ -C ₇ cycloalkyl group, or

R ₁ and R ₂ together with the nitrogen atom connecting them form a 5- or 6-membered heterocyclic ring,

R ₃ is C ₁ -C ₄ alkyl,

M is ammonium mono-, di-, tri-, or tetra-substituted with H, Na, Li, K, Ca, Mg, ammonium, or C ₁ -C ₄ alkyl and / or C ₂ -C ₄ hydroxyalkyl.

Preferably, in a compound of Formula 1 or a mixture of compounds of Formula 1, X ₁ , X ₂ , X ₃ and X ₄ are each independently —NH ₂ , —NHCN, —NHC ₁ -C ₄ alkyl, —NHC ₁ -C ₄ cyanoalkyl, -N (C ₁ -C ₄ alkyl) ₂ , -NHC ₂ -C ₄ hydroxyalkyl, -N (C ₂ -C ₄ hydroxyalkyl) ₂ , -N (C ₁ -C ₄ alkyl) (C ₂ -C ₄ hydroxyalkyl), -NH (C ₂ -C ₄ alkylene-C ₁ -C ₄ alkoxy), -N (C ₂ -C ₄ alkylene-C ₁ -C ₄ alkoxy ) ₂ , -NHC ₁ -C ₄ alkylphenyl, tetrahydrofurfurylamino, morpholino, piperidino, pyrrolidino, or cyclohexylamino or one or two alkyl groups having one or two carboxyl, carboxylate, carbonami a road and / or hydroxyl group, -OC ₁ -C ₁ -C ₄ alkyl, or a -NHC -N (C ₁ -C ₄ alkyl) ₂ moiety is substituted by _4-alkyl.

X ₁ and X ₃ are each independently —NH ₂ , —NHCH ₂ CH ₂ 0H, —N (CH ₂ CH ₂ 0H) ₂ or a morpholino residue,

X ₂ and X ₄ are each independently —NR ₁ R ₂ , wherein R ₁ and R ₂ are each independently hydrogen, cyano, methyl or ethyl groups, which are hydroxy, methoxy, carboxyl and salts thereof (— Or unsubstituted with one moiety selected from the group consisting of C0 ₂ M), or R ₁ and R ₂ together with the nitrogen atom form a complete morpholino ring),

Particular preference is given to compounds of the formula (1) or mixtures thereof, wherein M is hydrogen, sodium or ammonium.

X ₁ and X ₃ are both —NHCN, —NHCH ₂ CH ₂ 0H or —N (CH ₂ CH ₂ 0H) ₂ , and X ₂ and X ₄ are both —NHCH ₂ CH ₂ 0H, —N (CH ₂ In addition to compounds of formula (1) wherein CH ₂ 0H) ₂ or a morpholino residue and M is hydrogen or sodium, most particularly preferred compounds of formula (1) are X ₁ and X ₃ both -NH ₂ , X ₂ and X ₄ Are both —NR ₁ R ₂ wherein R ₁ is hydrogen, methyl, ethyl, 2-hydroxyethyl, —CH ₂ CO ₂ M, —CH ₂ CH ₂ CO ₂ M, or 2-methoxyethyl, R ₂ is hydrogen, methyl or 2-hydroxyethyl), or a compound of Formula 1 wherein X ₂ and X ₄ are both morpholino residues and M is sodium or ammonium.

Most particularly preferred mixtures of compounds of formula (1) are those in which both X ₁ and X ₃ are —NH ₂ together with two corresponding symmetrically substituted derivatives, ie the corresponding compounds of formula (1) in which X ₂ and X ₄ are identical; X ₂ is a morpholino residue, X ₄ is -NHCH ₂ CH ₂ 0CH ₃ , -NHCH ₂ CH ₂ OH, -N (CH ₂ CH ₂ 0H) ₂ or -NHCH ₂ C0 ₂ M, and M is sodium Asymmetric compounds.

The compound of formula 1 is a known compound or can be obtained by known methods.

Cationic polymers present as component (b) of the composition are preferably cationic starches, quaternized or unquaternized polyvinyl amines, polyallyl amines and poly-ethylene imines, dicyandiamide condensates, polyamide-polyamines. Resin and polyamide-epichlorohydrin resin, wherein cationic starch and most particularly poly-DADMAC (diallyl dimethyl ammonium chloride) are most preferred.

Preferably, the pigments present in the composition as fillers are inorganic pigments, which are, for example, natural or synthetic silica, clay, natural or precipitated calcium carbonate, calcium sulfite, pyrophyllite, kaolin, titanium oxide, aluminum hydroxide, Magnesium oxide, barium sulfate and talc, as well as mixtures thereof. Fillers may be added to the substrate to enhance certain properties (eg, smoothness, density or weight gain, porosity reduction and opacity increase).

In addition, the composition may contain binders, rheology and printability enhancing agents, fixatives, wet strength agents, antifoams and / or biocides as additional adjuvants. Examples of binders are polyvinyl alcohol, polyvinyl acetate, acrylic ester / styrene copolymers, carboxylated styrene / butadiene copolymers, polyvinyl pyrrolidone, oxidized starch, carboxymethyl cellulose and other water soluble cellulose derivatives, while For example, polyacrylamide and copolymers thereof may serve to improve rheology and printability.

The composition according to the invention can be applied to a substrate in a variety of ways. For example, fluorescent brighteners and cationic polymers can be applied as aqueous liquids by size press or film press.

Thus, a further aspect of the invention relates to a method of using a fluorescently whitened substrate, for example a foil suitable for inkjet printing, or a composition for producing paper, in particular, and a substrate obtained thereby, by means of a size press or film press application.

0.001 to 1% by weight, preferably 0.1 to 0.5% by weight of a fluorescent brightener of Formula 1 or a mixture thereof (a ₁ ) according to claim 1,

1 to 20%, preferably 2 to 15%, most preferably 7 to 12%, by weight of at least one cationic polymer (b ₁ ),

0-10% by weight of pigment and / or additional adjuvant (c ₁ ) and

A size press or film press liquid composition useful for fluorescent whitening a substrate suitable for inkjet printing, comprising an amount of water (d ₁ ) to be 100% by weight.

In addition, the composition may be applied to the substrate by coating using any type of coating device, such as a blade coater, roll coater, and the like, further aspects of the present invention

100 parts by weight of one or more inorganic pigments (a ₂ ),

0.01 to 1.2 parts by weight, preferably 0.1 to 0.8 parts by weight (based on the total weight of the pigment (a ₂ )) of the fluorescent brightener of Formula 1 or a mixture thereof (b ₂ ) according to claim 1,

0.1 to 10 parts by weight of one or more cationic polymers, in particular poly-DADMAC, quaternized or unquaternized polyvinyl amine, polyallyl amine, polyamide amine and polyethylene imine (c ₂ ) [total weight of pigment (a ₂ ) Based on and

A composition for fluorescent whitening of a substrate suitable for inkjet printing by coating the substrate with a coating paint having a solid content comprising 0 to 10 parts by weight of one or more adjuvants (d ₂ ) (based on the total weight of the pigment (a ₂ )). to be.

The coating paint is applied to the substrate as an aqueous composition containing 5 to 70% by weight, preferably 10 to 60% by weight, and 95 to 30% by weight, preferably 90 to 40% by weight of the solid composition described above.

The present invention therefore also relates to a method for producing a fluorescently whitened substrate suitable for inkjet printing by coating, for example a foil or in particular paper, and a substrate obtained thereby.

The following examples are intended to illustrate this without limiting the invention; Unless stated otherwise, parts and percentages are by weight.

Example

Table 1 below summarizes the fluorescent brighteners (FWA) of Formula 1 used for size presses and / or coating applications.

Formula 1

The compounds (101) to (117) may be known compounds or prepared by known procedures.

Size Press / Measure Size Press Application

0.22 g of a suitable FWA (see Table 1) in 100 g of an aqueous solution containing 8.0 g of cationic modified potato starch having a degree of substitution of 0.025, 0.1 g of hydrogenated starch hydrolyzate (polysorbate) and 1.8 g of a water-soluble acrylic copolymer as a solution. Add.

To simulate size press / meter size press application, the resulting solution is applied to one side of the substrate paper by a draw down rod so that the wet pick-up is 28%.

After drying and conditioning, the resulting sheets of ISO-fluorescence (F _ISO ) and whiteness (W _CIE ) are measured using a Datacolor Elrepho 3000 spectrophotometer.

The measurement results are summarized in Table 2 below.

Example number FWA number W _CIE ISO-fluorescence compare none 122.2 13.4 One (105) 142.3 19.2 2 (110) 134.1 16.0 3 (104) 146.0 20.2 4 (114) 137.2 17.0 5 (113) 136.6 16.8

Coating

28.5% solids consisting of 100 parts of silica (Gasil ^R M35), 30 parts polyvinyl alcohol (Mowiol ^R 4-98) based on the weight of the silica, and 2 parts poly-DADMAC based on the weight of the silica. A phosphorus aqueous coating paint is prepared and, based on the weight of silica, 0.4 parts of appropriate FWA (see Table 1) is added as a solution.

The final coating paint was applied to the medium sized substrate paper by an inlaid rod, and the paper was dried and conditioned to have a coating weight of 10 g / m 2, and the ISO-fluorescence (F _ISO ) and whiteness (W _CIE ) of the resulting sheet. ) Is measured using a Datacolor Elrepho 3000 spectrophotometer.

The measurement results are summarized in Table 3 below.

Example number FWA number W _CIE ISO-fluorescence compare none 74.5 0.0 6 (101) 115.9 12.3 7 (102) 115.1 12.1 8 (103) 114.0 11.9 9 (104) 113.7 11.4 10 (105) 113.4 11.5 11 (106) 113.0 11.6 12 (107) 113.0 11.4 13 (108) 112.9 11.7 14 (113) 112.8 11.4 15 (109) 112.8 11.4 16 (110) 112.7 11.4 17 (111) 111.2 11.2 18 A mixture of 105, 107, and 115 115.0 12.2 19 Mixture of 105, 114 and 116 113.4 11.7 20 A mixture of 103, 105 and 117 110.1 10.5

The paper obtained exhibits excellent printability and bleed fastness when used in an inkjet printer, in addition to clearly improving whiteness.

Claims (11)

Fluorescent brightener of Formula 1 or mixtures thereof (a), Cationic polymer (b), Water (c) and A composition for fluorescent brightening of a substrate suitable for inkjet printing, optionally comprising one or more pigments and / or one or more additional adjuvants (d). Formula 1

In Formula 1 above, X ₁ , X ₂ , X ₃ and X ₄ are each independently of each other —NR ₁ R ₂ or —OR ₃ , R ₁ and R ₂ independently of one another are hydrogen, cyano, C ₁ -C ₄ alkyl group wherein the alkyl group is C ₁ -C ₄ alkoxy, hydroxy, carboxyl or salt thereof (-C0 ₂ M), cya Furnace, carboxamido, thiol, guanidine, substituted or unsubstituted phenyl, unsubstituted or C ₁ -C ₄ alkyl-substituted C ₅ -C ₈ cycloalkyl, halogen, heterocycle and sulfonic acid residues selected from the group consisting of Is substituted or unsubstituted with one or two moieties and the carbon chain of an alkyl group having 2, 3 or 4 carbon atoms may be interrupted by oxygen) or a C ₅ -C ₇ cycloalkyl group, or R ₁ and R ₂ together with the nitrogen atom connecting them form a 5- or 6-membered heterocyclic ring, R ₃ is C ₁ -C ₄ alkyl, M is ammonium mono-, di-, tri-, or tetra-substituted with H, Na, Li, K, Ca, Mg, ammonium, or C ₁ -C ₄ alkyl and / or C ₂ -C ₄ hydroxyalkyl. The compound of claim ₁ , wherein X ₁ , X ₂ , X ₃ and X ₄ are each independently —NH ₂ , —NHCN, —NHC ₁ -C ₄ alkyl, —NHC ₁ -C ₄ cyanoalkyl, —N (C ₁ -C ₄ alkyl) ₂ , -NHC ₂ -C ₄ hydroxyalkyl, -N (C ₂ -C ₄ hydroxyalkyl) ₂ , -N (C ₁ -C ₄ alkyl) (C ₂ -C ₄ hydroxy Alkyl), -NH (C ₂ -C ₄ alkylene-C ₁ -C ₄ alkoxy), -N (C ₂ -C ₄ alkylene-C ₁ -C ₄ alkoxy) ₂ , -NHC ₁ -C ₄ alkylphenyl , Tetrahydrofurfurylamino, morpholino, piperidino, pyrrolidino, or cyclohexylamino, or one or two carboxyl, carbonate, carboxamido and / or hydroxyl groups of an alkyl group, -OC _1- the C ₄ alkyl substituted with -NHC ₁ -C ₄ alkyl or -N (C ₁ -C ₄ alkyl) ₂ moiety of the composition. The method according to claim 1 or 2, X ₁ and X ₃ are each independently —NH ₂ , —NHCH ₂ CH ₂ 0H, —N (CH ₂ CH ₂ 0H) ₂ or a morpholino residue, X ₂ and X ₄ are each independently —NR ₁ R ₂ , wherein R ₁ and R ₂ are each independently hydrogen, cyano, methyl or ethyl groups, which are hydroxy, methoxy, carboxyl and salts thereof (— Or unsubstituted with one moiety selected from the group consisting of C0 ₂ M), or R ₁ and R ₂ together with the nitrogen atom form a morpholino ring), Wherein M is hydrogen, sodium or ammonium. The component (b) according to any one of claims 1 to 3, wherein the component (b) which is a cationic polymer is cationic starch, quaternized or unquaternized polyvinyl amine, polyallyl amine, poly-ethylene imine, dicyandiamide A composition selected from the group consisting of condensates, polyamide-polyamine resins and polyamide-epichlorohydrin resins. The composition according to any one of claims 1 to 4, wherein the pigment which is a filler is an inorganic pigment. The composition according to any one of claims 1 to 5, which contains, as further auxiliaries, binders, rheology and printability improving agents, fixatives, wet strength agents, antifoaming agents and / or biocides. 0.001 to 1% by weight of a fluorescent brightener according to claim 1 or a mixture thereof (a ₁ ), 1-20% by weight of one or more cationic polymers (b ₁ ), 0-10% by weight of pigment and / or additional adjuvant (c ₁ ) and A size press or film press liquid composition useful for fluorescent whitening a substrate suitable for inkjet printing, comprising an amount of water (d ₁ ) to be 100% by weight. A method for fluorescent whitening a substrate suitable for ink jet printing by applying the composition according to claim 7 to the substrate by a size press or film press method. 100 parts by weight of one or more inorganic pigments (a ₂ ), 0.01 to 1.2 parts by weight of a fluorescent brightener of formula 1 or a mixture thereof (b ₂ ) according to claim 1 based on the total weight of pigment (a ₂ ), 0.1 to 10 parts by weight of at least one cationic polymer (c ₂ ), based on the total weight of pigment (a ₂ ); and A coating material for fluorescent whitening of a substrate suitable for inkjet printing, having a solid content comprising 0 to 10 parts by weight of one or more adjuvants (d ₂ ) (based on the total weight of the pigment (a ₂ )). A method for fluorescent whitening a substrate suitable for inkjet printing by coating the substrate with an aqueous composition comprising 30 to 95 weight percent water and 70 to 5 weight percent composition according to claim 9. A substrate which is fluorescently whitened according to the method of claim 8 or the method of claim 10.