EP2061824A1

EP2061824A1 - Polyurethane derivates and corresponding uses and methods for producing watermarks

Info

Publication number: EP2061824A1
Application number: EP07786055A
Authority: EP
Inventors: Josep Rocas Sorolla
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-07-17
Filing date: 2007-07-13
Publication date: 2009-05-27
Also published as: WO2008009388A1; WO2008009388A8; ES2265300B1; ES2265300A1

Abstract

Polyurethane derivates and corresponding uses and methods for producing watermarks. The invention relates to compounds and/or compositions for producing watermarks on paper, having general formula (I), where, for example, R and R' are polyethyleneglycol, X, X' and X' are a diisocyanate, A is a polyester with a single branch, consisting in a functional carboxylic acid group, m and n are 0 or 1, and B is a diol. The molecular weight of the compound is greater than 550, and the NCO value is equal to 0. The invention also relates to methods for producing watermarks and to uses of compounds having general formula (I) and compositions containing them to produce watermarks on cellulosic sheet materials.

Description

POLYURETHANE DERIVATES AND CORRESPONDING USES AND METHODS

FOR PRODUCING WATERMARKS

DESCRIPTION

Field of the invention

The invention relates to compounds and/or compositions for producing watermarks in cellulosic sheet materials, in particular the invention relates to compounds having the general formula (I)

R— X— (A— X)_m-(-B— X-)_n-R' (I)

and compositions containing them. The invention also relates to methods for producing watermarks on cellulosic sheet materials and to uses of compounds having the general formula (I) and compositions containing them for producing watermarks on cellulosic sheet materials.

State of the art

Various compositions and methods for producing watermarks are known. However, it is usually necessary to use compositions containing substances that are more or less toxic and/or difficult to handle. In addition, they are methods that are suitable for manufacturing large batches, and therefore they are expensive to apply to the production of small or medium size batches.

Document ES 2.115.002 describes printing inks based on polyurethane resins that have a high molecular weight. These resins have some dense portions in urethane links and other scarce portions in urethane links and they are particularly designed for use on plastic bags and packaging containers.

Document US 6.933.329 describes some inks for ink jet printing systems that comprise some polyurethanes with molecular weights between 4791 and 7530. Document US 5.973.062 describes the chemical combination between some colouring agents and some polyurethanes for producing inks for rotogravure printing.

At any event, it must be taken into account that the requirements that an ink must fulfil and the requirements that a composition for producing a watermark must fulfil are completely different, as will be discussed later.

Disclosure of the invention

The aim of the invention is to overcome these drawbacks. This purpose is achieved by means of a compound having the general formula

R— X-(-A— X'-)_m-(-B-X"-)_n-R' (I)

where

R and R' are monoethyleneglycol, polyethyleneglycol having a molecular weight less than 1500, polyethyleneglycol monoether having a molecular weight less than 1500, primary or secondary monoamine with a molecular weight less than or equivalent to 2000, or mixtures thereof,

X, X' y X" are an aliphatic diisocyanate with a molecular weight less than 1000, preferably less than 500,

A is an aliphatic linear polyester with a molecular weight less or equal than 1000, an aliphatic polyester with single branching, consisting of a functional carboxylic acid group or a -SO₃H group, with a molecular weight less or equal than 1000, an aliphatic linear polyester with a molecular weight less or equal than 1000, an aliphatic polyester with single branching, consisting in a functional carboxylic acid group or a -SO₃H group, with a molecular weight less or equal than 1000, an aliphatic linear polycaprolactone with a molecular weight less or equal than 1000, or an aliphatic polycaprolactone with a single branching, consisting of a functional carboxylic acid group or a -SO₃H group, with a molecular weight less or equal than 1000,

m is 0 or 1

B is an aliphatic diol with a molecular weight less than 1000 and with a single branching, consisting in a functional carboxylic acid group or a -SO₃H group,

n is 0 or 1 ,

where the molecular weight of said compound is between 550 and 4000, preferably excluding that it has a molecular weight of 1000,

and where the NCO value is equivalent to 0.

In fact, the compounds having general formula (I) allow a combination of properties to be obtained, which makes them particularly suitable for use in the production of watermarks. They are non-reactive oligourethanes, since they do not have any free NCO groups. These compounds have a low viscosity (owing to their reduced molecular weight, the few or non-existent side branching and the virtually nonexistent cross-linking), a high penetration level in a cellulosic sheet material, a low sideways migration and a good solidity with respect to water and organic solvents (thanks to the oligourethane affinity to cellulosic material and, in the case where a functional carboxylic acid group or -SO₃H lateral group is present, thanks to their reactive nature with the cellulosic material), they are soluble or can disperse in aqueous solutions and/or in organic solvents, they are easy to handle, etc. Moreover, they have numerous ether groups or -CH₂- which means that they have a low refraction index, in fact their refraction index is between 1.5 and 1.6. Preferably they have an index value close to 1.54 (for example, between 1.52 and 1.56), which requires limiting the amount of functional polar groups, and therefore a compromise solution must be reached between the attachment capacity to the cellulosic material, the refraction index and the viscosity. All this provides a series of advantages, such as the fact that a highly transparent watermark is obtained, with well defined contours, that are hardly affected if a drop of water or an organic solvent drops on them (in other words, the watermark is fixed well to the cellulosic material) and the machinery and the tools used to produce the watermark can be cleaned easily afterwards. These compounds are also very simple and versatile.

In general, it is advantageous that the compound contains a (and preferably only one) functional carboxylic acid group or a -SO₃H group, or, in general, a functional anionic type group. This way, the solidity of the watermark can be improved without compromising the capacity to penetrate the cellulosic material. It is particularly advantageous that the functional group be carboxylic acid owing to its weak acidity, which favours the conversion of carboxylate (which is its initial format, when applied) into carboxylic on the substrate, which, in the presence of water and solvents, has a solider structure than the carboxylate.

Preferably the primary or secondary monoamines comprise a solubilising group that advantageously is a polyethyleneglycol, a carboxylic acid or a sulfonic acid.

Advantageously the molecular weight of compound (I) is between 550 and 2500, and preferably between 550 and 1500.

Advantageously, if the molecular weight of R and R' is greater than 1000, then m and n are equal to 0.

A preferable alternative is that compound (I) is linear. Generally, the viscosity is a very important parameter when producing watermarks. If viscosity is too low it can lead to problems of insufficient solidity, and excessive sideways migration, etc. On the other hand, if viscosity is too high it can create problems of poor penetrability. Generally, a linear compound will have a lower viscosity than a branched compound. For its part, branching will affect viscosity to a greater or lesser degree according to the properties thereof: the presence of lateral polar groups (such as for example -OH type) will consequently form hydrogen bridge type links, etc. (forming a certain degree of cross-linking), which affects viscosity to a greater degree; the presence of other lateral ionic or polar groups can also considerably affect viscosity such as, for example, carboxylic acid or -SO₃H groups. Therefore, another preferable alternative is that the compound be linear with the sole exception of having a lateral group comprising the said carboxylic acid or -SO₃H groups.

A preferible alternative is that the polyethyleneglycol monoether be polyethylene monomethlyether with a molecular weight less than 1500.

Another advantageous alternative is when R and R' are linear and crystalline or semicrystalline polyethyleneglycols, such as for example PEG 400, as a compound is obtained that has a suitable viscosity and a refraction index close to that of the cellulosic material.

Preferably the amine is monoethanolamine, diethanolamine, polyoxyalkylenemonoamine, metoxypropylamine, 2-aminoethanesulfonic acid

(taurine), 3-aminopropanesulfonic acid (homotaurine), or aminoacetic acid (glycine).

Particularly, the polyoxyalkylenemonoamine is preferably a primary monoamine linked to a polyether, where the polyether is made from a mixture of ethylene oxide

(EO) and propylene oxide (PO). These compounds are sold by Huntsman Corporation under the general name of Jeffamine®. Preferably the molar ratio between PO and EO is 9/1 and the molecular weight is 600 (sold under the name of

XTJ-505 (M-600)), or the molar ratio between PO and EO is 3/19 and the molecular weight is 1000 (sold under the name of XTJ-506 (M-1000)), or the molar ratio between PO and EO is 29/6 and the molecular weight is 2000 (sold under the name of XTJ-507 (M-2005)), or the molar ratio between PO and EO is 10/31 and the molecular weight is 2000 (sold under the name Jeffamine® M-2070)).

Preferably X, X' and X" are hexamethylene diisocyanate, isoforon diisocyanate (IPDI), dicyclohexylmethyl diisocyanate, tetramethylxylylene diisocyanate, xylylene diisocyanate, or trimethylhexamethylene diisocyanate.

Advantageously the polyester is made from an aliphatic linear diol from the group made up of ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, neopentylglycol 2,2-

(bishydroxymethyl)propionic acid, and an aliphatic linear diacid. It is particularly advantageous that the diol be butanediol and that the diacid be adipic acid.

Preferably the polyester is crystalline or semicrystalline as in this case a watermark is obtained that has a more solid structure in the presence of water and organic solvents.

Advantageously the polyester is made from an aliphatic linear diol from the group made up of ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, and neopentylglycol.

Preferably the polycaprolactone is made from a gamma-caprolactone and using as the chain initiator an aliphatic linear from the group containing ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, neopentylglycol, and 2,2-(bishydroxymethyl)propionic acid. It is particularly interesting that the polycaprolactone be made from 2,2-(bishydroxymethyl)propionic acid as chain initiator. An example of these polycaprolactones is the product sold under the name of HC 1 100® by Solvay Caprolactones (which is a division of Solvay S. A.), which is a caprolactone polyester that includes a diol in the chain and which has a free lateral acid group. It has a molecular weight of 1000, an OH value of 100 mg KOH/g, an acid value less than 60 mg KOH/g and a melting point between 4O⁰C and 45⁰C.

A preferable alternative is that A be a compound from the group containing hexanediol adipate, butanediol adipate, neopentylglycol adipate, 2- methylpropanodiol adipate, diethyleneglycol adipate, and mixture of these.

Advantageously B is 2,2-(bishydroxymethyl)propionic acid.

A preferable embodiment of compound (I) is when n is 0 if m=1 and A is branched, consisting in a functional carboxylic acid group or a -SO₃H group. It is particularly advantageous that the functional group be carboxylic acid. Another preferable embodiment of compound (I) is when n is 1 if m= 0 or if m=1 and A is linear. In fact, in this case group B can provide the branching with the functional carboxylic acid group or the -SO₃H group.

Another preferable alternative of compound (I) is when m is 0 and n is 0.

Advantageously compound (I) comprises a colouring agent. In fact, a preferable embodiment of the invention is obtained when a colouring agent is included, so that the resulting watermark is coloured. The colouring agent can be included so that it is chemically linked to the compound (so that the compound, overall, comprises the colouring agent), or it can be included in the composition used to make the watermark, as a further component thereof. At any event it is advantageous that it has some group that is suitable for reacting with the cellulosic substrate and with some functional polyurethane group, such as for example a reactive halogen group. Some examples of these colouring agents are the Drimaren colouring agents sold by the Pigments and Additives division, of the Clariant Group. In the event that the colouring agent is chemically linked to compound (I), it is advantageous that it be linked to the compound by means of a urethane bond formed by an -OH group of the colouring agent and an NCO group of the compound. Some examples of the colouring agents of this type are the Reactint® colouring agents, sold by Milliken Chemical, which is a division of Milliken & Company. It may also be interesting to combine colouring agents of both types, depending of the colour to be obtained.

Preferably the compound contains the colouring agent is a proportion less than or equivalent to 0.5% by weight, preferably less than or equivalent to 0.4% by weight with respect to the total weight of the compound, both in the event that the colouring agent is chemically linked to the compound and in the event that both are dissolved and/or dispersed in a composition. It has been observed that using higher percentages deteriorates the quality of the transparency of the watermark, because the refraction index of the colouring agent (particularly red and blue) is higher than the refraction index of the cellulosic material. A preferable embodiment of the invention is obtained when a composition is prepared and used that comprises at least a first compound having the general formula (I) according to the invention, where R, R', X₁ X', X", A, m, B, and n have the general meaning indicated above, and a solvent, preferably water, ethanol, isopropanol or metoxypropanol. In fact, in order to produce and use compound (I) appropriately it is advisable to dilute it and/or disperse it in a solvent. On the one hand, this makes it easier to produce and, on the other hand, it makes its application and penetration into the cellulosic material easier.

Preferably the composition comprises at least a second compound having general formula (I), where the second compound has a different molecular weight to the first compound. This way it is possible to adjust the viscosity of the composition. So, for example, when the synthesis is done in two stages the viscosity and attachment to the substrate (cellulose) can be adjusted; in other words, a balance is achieved between a low viscosity and a good fixation. Normally, the mixture is made between a product that has adheres or fixes well to cellulosic (but is quite viscose depending on the type of paper, particularly thick, dense paper) and another one that is more fluid and which even gives more transparency (because it is less functionalized, does not have carboxylic groups or has less of them, and has an even lower refraction index)

The composition can comprise a cosolvent which, preferably is an alcohol, preferably ethanol, isopropanol or metoxypropanol. Alternatively it can be an advantage if the cosolvente is N-methylpyrrolidone. Another interesting alternative is obtained when the main solvent is an alcohol and it has water as its cosolvent, in small proportions. This way, with a small amount of water, a composition can be obtained that is suitable for using with water sensitive cellulosic materials (for example, owing to wrinkling problems). It must be taken into account that it is very normal to use alcohols that contain small amounts of water (such as for example, ethanol). Generally, it is an advantage that the composition has a water content less than 15% by weight with respect to the overall weight of the compound having general formula (I) in the event that it has to be used with a cellulosic material that is affected by water.

In the event that the compound is dispersed in an aqueous solution, preferably the particle size of the dispersion is less than 10 nanometers, to obtain a good penetration.

It is particularly advantageous that the composition be a mixture of a first compound having general formula (I) with a branch consisting of a functional carboxylic acid group or a -SO₃H group and at least one second compound having general formula (I) with no branch consisting of a functional carboxylic acid group or a -SO₃H group, where said second compound has m and n equal to 0.

Preferably, in the composition the concentration of compounds having general formula (I) is between 50-70% by weight with respect to the overall weight of the composition having general formula (I). These concentrations are the most suitable for use in the production of watermarks. Concentrations less than 50% make the watermark transparency insufficient because the pores of the cellulosic material are not filled sufficiently with the compound having general formula (I). It is also It is also advantageous that the concentration of compounds having general formula (I) be between 70-90% by weight with respect to the overall weight of the composition having general formula (I), and it is preferably 80%. In fact, these concentrations are more suitable in terms of production, transport and distribution. Higher concentrations make the composition too viscose to be handled during the production method.

Preferably the composition comprises, in addition, a volatile amine that forms a salt with said carboxylic acid or -SO₃H, and very preferably said volatile amine is ammonium or triethylamine. The salt obtained in this way is water soluble or dispersible and soluble in organic solvents (for example, an alcohol) if an appropriate amount is used. Once applied to the cellulosic material, and once the solvent has evaporated, the volatile amine is removed and the compound acidifies itself. Therefore, the compound in its acid format attaches better to the cellulosic material and it is harder to redissolve.

The invention also relates to the use of a compound having general formula (I) according to the invention, where R, R', X, X', X", A, m, B, and n have the general meaning indicated above, for producing watermarks on a cellulosic sheet material.

The invention also relates to the use of a composition according to the invention, for the production of a watermark on a cellulosic sheet material.

Generally, in this specification and claims, when it is indicated that A and B (or the compound on the whole) are linear or have a single branch consisting of a functional carboxylic acid group of a -SO₃H group, it must be understood in the sense that A and B do not have other branches capable of producing cross-linking. Generally, the branches capable of producing cross-linking are known by a person skilled in the art. In the event cross-linking occurs, viscosity is increased considerable, which acquires too high a value. There, A and B can include other branches, preferably of the alkylic type but also branches that include some additional functional group providing that cross-linking does not occur because of said additional functional group. Particularly, A and B can have -CH₃ lateral groups.

The invention also relates to a method for the production of a watermark on a cellulosic sheet material characterized in that it comprises a stage of applying a compound having general formula (I) according to the invention, or a composition according to the invention, to the cellulosic sheet material using flexography or an intaglio printing process. In fact, conventionally the watermark is produced during the paper manufacturing method. To do this rollers with relief drawings are used, generally arranged at a point before the continuous web of wet paper enters the dryers. This way, the web's cellulosic fibres move horizontally (in the direction of the actual paper) so that the paper is thinner and, consequently, more transparent in the area bearing the motif or watermark. Therefore, the rolls with relief drawings "deform" the wet paper so that this deformation remains permanently on the paper after drying. Another conventional method for producing motifs or watermarks, and which is also carried out when producing the paper, consists in using a tight band around a roller, which bears a relief drawing or the configuration of a watermark. This relief drawing comes into contact with the wet paper, which still has a certain degree of plasticity, which allows it to be compressed. The area of compressed paper has a smaller amount of trapped air and, therefore, a lower light refraction, which increases the paper's transparency. Consequently, watermarks are currently produced during the paper manufacturing process and they are white and black (in other words, generally, in one colour according to the colour of the paper) because they only deal with transparency, shading and opacity.

This invention provides for the production of watermarks on papers (generally, cellulosic sheet materials) that have already been produced, in a subsequent stage corresponding to the printing phase. Also, this invention provides for the production of watermarks in colours. In fact, the compounds and compositions according to the invention can be used as inks for flexography and/or intaglio printing (also known as rotogravure printing). These printing techniques use liquid inks (with a low viscosity) that essentially consist of a solvent and a series of additives (colouring agents, resins, pigments, waxes or plastifying agents, etc.). The liquid inks are applied to the cellulosic support material and the solvent evaporates. When using the compounds and compositions according to the invention, these penetrate inside the cellulosic material reducing its refraction, therefore managing to produce a watermark.

Detailed description of some embodiments of the invention

Example 1

150.00 grams of CAPA HC1 100 (Solvay) were heated to 100⁰C with a constant flow of N₂ for ¹/4 hour to remove the water. This was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until a NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed. Therefore, this example was as follows:

R=R'=PEG 300 X=X'=IPDI A=CAPA HC1100 m=1 n=0

CAPA^® HC 1100 is a commercial name of a polycaprolactone polyester diol with a pendant carboxylic functional group commercialised by Solvay. It has a molecular weight of 1000 and a typical OH value of 110 mg KOH/g.

Example 2

150.00 grams of CAPA HC1 100 (Solvay) together with 4.00 grams of Reactint Blue X3LV (Milliken) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was maintained at this temperature until a NCO of approximately 5.44 was obtained.

Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 3

150.00 grams of CAPA HC1 100 (Solvay) together with 4.00 grams of Reactint Red X65 (Milliken) were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 4 150.00 grams of CAPA HC1 100 (Solvay) together with 4.00 grams of Reactint Yellow X15 (Milliken) were heated to 100⁰C with a constant flow of N₂ during 14 hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 5

15OmOO grams of CAPA HC1 100 (Solvay) were heated to 100⁰C with a constant flow of N₂ during ^ΛΛ hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0, 4.00 grams of Drimaren Blau HF-RL (Clariant) were added. Then 14 hour later the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 6

150.00 grams of CAPA HC1100 (Solvay) were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to O₁ 4.00 grams of Drimaren Rot HF-G (Clariant). Then !4 hour later the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 7 150.00 grams of CAPA HC1100 (Solvay) ) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 80⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0, 4.00 grams of Drimaren GeIb HF-R (Clariant). Then V₂ hour later the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 76.67 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 8

150.00 grams of butanodiol adipate with molecular weight 1000, 9.91 grams of 2,2- (bishydroxymethyl)propionic acid (DMPA) and 9.91 grams of N-methylpyrrolidone (NMP) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 74.65 grams of IPDI. It was kept at this temperature until an NCO of approximately 4.01 was obtained. Then 168.48 additional grams of IPDI were added followed by 521 ,94 grams of PEG 300. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 7.10 grams of triethylamine were added. Then 223.81 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

This example was as follows:

R=R'=PEG 300 X=X'=IPDI

A=polyester formed from butanodiol adipate m=1

B=DMPA n=1

Example 9

150.00 grams of polypropyleneglycol (PPG) of molecular weight 1000, 20.12 grams of DMPA and 20.12 grams of NMP were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 100.00 grams of IPDI. It was kept at this temperature until an NCO of approximately 4.66 was obtained. Then 90.00 grams of PEG 300 were added. When the NCO was equal to 0 the reaction was cooled to 6O⁰C and 14.42 grams of triethylamine were added. Then 73.51 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 10

300.00 grams of PEG 600 were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed

Example 11

300.00 grams of PEG 600 together with 4.00 grams of Reactint Blue X3LV (Milliken) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed

Example 12

300.00 grams of PEG 600 together with 4.00 grams of Reactint Red X65 (Milliken) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed

Example 13

300.00 grams of PEG 600 together with 4.00 grams of Reactint Yellow X15 (Milliken) were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed

Example 14

300.00 grams of PEG 600 were heated to 100⁰C with a constant flow of N₂ during Y₂ hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 4.00 grams of Drimaren Blau HF-RL (Clariant) were added. Then Vi hour later the reaction was cooled to 6O⁰C and 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 15

300.00 grams of PEG 600 together with 4.00 grams of Reactint Blue X3LV (Milliken) were heated to 100⁰C with a constant flow of N₂ during !4 hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 4.00 grams of Drimaren Rot HF-G (Clariant) were added. Then Vz hour later the reaction was cooled to 6O⁰C and 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 16

300.00 grams of PEG 600 together with 4.00 grams of Reactint Blue X3LV (Milliken) were heated to 100⁰C with a constant flow of N₂ during !4 hour to extract the water. It was then cooled to 8O⁰C to add 55.57 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. Then 4.00 grams of Drimaren GeIb HF-R (Clariant) were added. Then 14 hour later the reaction was cooled to 6O⁰C and 88.89 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed. Ejemplo 17

300.00 grams of PEG 300 were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 111.14 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. The reaction was cooled to 6O⁰C and 102.78 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 18

300.00 grams of PEG 400 were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 83.86 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. The reaction was cooled to 6O⁰C and 95.84 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 19

300.00 grams of PEG 1000 were heated to 100⁰C with a constant flow of N₂ during V₂ hour to extract the water. It was then cooled to 8O⁰C to add 33.34 grams of IPDI.

It was kept at this temperature until an NCO of approximately 0 was obtained. The reaction was cooled to 6O⁰C and 83.33 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 20

300.00 grams of PEG 1500 were heated to 100⁰C with a constant flow of N₂ during

V₂ hour to extract the water. It was then cooled to 8O⁰C to add 22.23 grams of IPDI.

It was kept at this temperature until an NCO of approximately 0 was obtained. The reaction was cooled to 6O⁰C and 83.33 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed. Example 21

300.00 grams of PEG 800 were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 41.675 grams of IPDI. It was kept at this temperature until an NCO of approximately 0 was obtained. The reaction was cooled to 6O⁰C and 83.33 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 22 100.00 grams of Hoopol 523 (Synthesia) (butanediol polyadipate with a molecular weight of 1000), 14.19 grams of PEG 300 and 13.41 grams of DMPA were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 63.87 grams of IPDI. It was kept at this temperature until an NCO of approximately 1.75 was obtained. The reaction was cooled to 6O⁰C and 47.87 grams of metoxypropanol were added. Then 9.61 grams of triethylamine were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 23 100.00 grams of Hoopol 523 (Synthesia), 30.00 grams of PEG 300 and 26.83 grams of DMPA were heated to 100⁰C with a constant flow of N₂ during ^ΛA hour to extract the water. It was then cooled to 8O⁰C to add 133.37 grams of IPDI. It was kept at this temperature until an NCO of approximately 4.66 was obtained. The reaction was cooled to 60⁰C and 72.55 grams of metoxypropanol were added. Then 19.23 grams of triethylamine were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 24

150.00 grams of CAPA HC1100 (Solvay) were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of isoforon diisocyanate (IPDI). It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 82.91 additional grams of IPDI were added followed by 313.78 grams of polyethyleneglycol (PEG) 300. When the NCO was equal to O₁ the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 153.34 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

In this case, the composition obtained is substantially a mixture of the compositions in Examples 1 and 17 above.

In fact, this example is a specific case of a particularly advantageous embodiment of the invention, both from the point of view of the composition and from the point of view of the production method used. In fact, very good results are obtained with compositions that contain a mixture of one component that has a lateral carboxylic acid group, forming a salt with the triethylamine and one component without any lateral carboxylic acid group.

Example 25

150.00 grams of CAPA HC1100 (Solvay) together with 4.00 grams of Reactint Blue X3LV (Milliken) were heated to 100⁰C with a constant flow of N₂ during Vz hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 82.91 additional grams of IPDI were added followed by 313.78 grams of PEG 300. When the NCO was equal to 0, the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 153.34 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 26

150.00 grams of CAPA HC1100 (Solvay) together with 4.00 grams of Reactint Red X65 (Milliken) were heated to 100⁰C with a constant flow of N₂ during Vi hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 82.91 additional grams of IPDI were added followed by 313.78 grams of PEG 300. When the NCO was equal to 0, the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 153.34 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 27

150.00 grams of CAPA HC1100 (Solvay) together with 4.00 grams of Reactint Yellow X15 (Milliken) were heated to 100⁰C with a constant flow of N₂ during Vz hour to extract the water. It was then cooled to 8O⁰C to add 66.69 grams of IPDI. It was kept at this temperature until an NCO of approximately 5.44 was obtained. Then 82.91 additional grams of IPDI were added followed by 313.78 grams of PEG 300. When the NCO was equal to 0, the reaction was cooled to 6O⁰C and 12.34 grams of triethylamine were added. Then 153.34 grams of metoxypropanol were added. The reactor was cooled to room temperature and the reaction was considered to have been completed.

Example 28

294.6 grams (0.472 moles) of diethyleneglycol polyadipate (Glypol 3020 by Condensia) with a molecular weight of 620 were loaded into the reactor under a constant flow of dry nitrogen, followed by 210 g (0.944 moles) of IPDI. It was left to react at 60 ⁰C cooling it to maintain the temperature and not let it go beyond 60 ⁰C₁ until NCO=8.4% (assessed using the dibutylamine method). Then 295.4 grams of PEG 300 were added and the reaction was left to continue at the same temperature. When the NCO reached 0.03 %, the reaction was cooled to 4O⁰C and 200 grams of metoxypropanol were added. The reactor was cooled to room temperature and it was unloaded. This is one of the particularly preferable solutions of the invention. Alternatively, the colouring agents can be added at the end, with the metoxypropanol, at 0.2 % in the case of yellow, (2 g in the 200 g of metoxypropanol for the 800 g of material), and at 0.1 % in the case of red and blue (1 g in the 200 g of metoxypropanol for the 800 g of material), the colours being Reactint Blue X3LV, Reactint Red X65, and Reactint Yellow X15, all by Milliken.

The compounds according to the invention can also be used for the production of watermark using the offset system. In other words, the invention also relates to a method for producing a watermark on a cellulosic sheet material characterized in that it comprises a stage of applying a compound having general formula (I) according to the invention, or a composition according to the invention, where R, R', X, X', X", A, m, B, and n have the general meaning indicated above, to the cellulosic sheet material using offset.

In fact, the properties of a material suitable for use in flexography must be different to the properties of a material that is suitable for use in offset. To be used in offset, the products must be hydrophobic and soluble in organic, non-polar solvents. However, a suitable choice of R, R', X, X¹, X" A, B, m and n enables products suitable for use in offset to be obtained. In this respect, it is particularly advantageous that m and n be 0. Preferably the products will have a low molecular weight (between 550 and 1500). Moreover, the composition will have to use non- polar solvents, such as for example alkylobenzenes, to be suitable for use in offset.

Claims

1.- Compound having general formula

_R_χ.(._A— X^>-)_m-(-B— X"-)n-R' (I)

Where

X₁ X' y X" are an aliphatic diisocyanate with a molecular weight less than 1000, preferably less than 500,

m is 0 or 1

B is an aliphatic diol with a molecular weight less than 1000 and with a single branching, consisting in a functional carboxylic acid group or a -SO₃H group, n is 0 or 1 ,

where the molecular weight of said compound is between 550 and 4000,

and where the NCO value is equivalent to 0.

2.- Compound according to claim 1 , characterized in that its molecular weight is between 550 and 2500, and preferably between 550 and 1500.

3.- Compound according to one of the claims 1 or 2, characterized in that it is linear.

4.- Compound according to any of the claims 1 to 3, characterized in that said polyethyleneglycol monoether is polyethylene monomethlyether with a molecular weight less than 1500.

5.- Compound according to any of the claims 1 to 4, characterized in that said amine is monoethanolamine, diethanolamine, polyoxyalkylenemonoamine, metoxypropylamine, 2-aminoethanesulfonic acid, 3-aminopropanesulfonic acid, or aminoacetic acid.

6.- Compound according to any of the claims 1 to 5, characterized in that X, X' and X" are hexamethylene diisocyanate, isoforon diisocyanate, dicyclohexylmethyl diisocyanate, tetramethylxylylene diisocyanate, xylylene diisocyanate, or trimethylhexamethylene diisocyanate

7.- Compound according to any of the claims 1 to 6, characterized in that said polyester is made from an aliphatic linear diol from the group made up of ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, neopentylglycol 2,2-(bishydroxymethyl)propionic acid, and an aliphatic linear diacid.

8.- Compound according to claim 7, characterized in that said diol is butanediol and said diacid is adipic acid.

9.- Compound according to any of the claims 1 to 8, characterized in that said polyester is made from an aliphatic linear diol from the group made up of ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, and neopentylglycol.

10.- Compound according to any of the claims 1 to 9, characterized in that said polycaprolactone is made up of a gamma-caprolactone and using as the chain initiator an aliphatic linear from the group containing ethyleneglycol, hexanediol, butanediol, propyleneglycol, diethyleneglycol, methylpropylglycol, neopentylglycol, and 2,2-(bishydroxymethyl)propionic acid

11- Compound according to any of the claims 1 to 6, characterized in that A compound from the group containing hexanediol adipate, butanediol adipate, neopentylglycol adipate, 2-methylpropanodiol adipate, diethyleneglycol adipate, and mixture of these

12.- Compound according to any of the claims 1 to 11 , characterized in that said polycaprolactone is made up of 2,2-(bishydroxymethyl)propionic acid as the chain initiator.

13.- Compound according to any of the claims 1 to 12, characterized in that B is 2,2- (bishydroxymethyl)propionic acid.

14.- Compound according to any of the claims 1 to 13, characterized in that n is 0 if m=1 and A is branched, consisting in a functional carboxylic acid group or a -SO₃H group.

15.- Compound according to any of the claims 1 to 13, characterized in that n is 1 if m= 0 or if m=1 and A is linear.

16.- Compound according to any of the claims 1 to 13, characterized in that m is 0 and n is 0.

17.- Compound according to any of the claims 1 to 16, characterized in that it comprises a colouring agent, where said colouring agent is linked to said compound by an -OH group of the colouring agent and an NCO group of the compound thereby replacing one of said R, A, B or R', and where the molecular weight of said compound is between 550 and 1500.

18.- Compound according to claim 17, characterized in that said colouring agent is linked to said compound by an -OH group of the colouring agent and an NCO group of the compound.

19.- Compound according to one of the claims 17 or 18, characterized in that said compound contains said colouring agent in a proportion that is less than or equal to 0.5% by weight, preferably less than or equal to 0.4% by weight with respect to the overall weight of the compound.

20.- Composition comprising at least a first compound having general formula (I) according to any of the claims 1 to 19, where R, R¹, X, X', X", A, m, B, and n have the general meaning indicated above, and a solvent preferably water, ethanol, isopropanol or metoxypropanol.

21.- Composition according to claim 20, characterized in that it comprises at least a second compound having general formula (I), where said second compound has a different molecular weight to said first compound.

22.- Composition according to one of the claims 20 or 21 , characterized in that it comprises a cosolvent.

23.- Composition according to claim 22, characterized in that said cosolvent is an alcohol.

24.- Composition according to claim 23, characterized in that said alcohol is ethanol, isopropanol or metoxypropanol.

25.- Composition according to claim 22, characterized in that said cosolvent is N- methylpyrrolidone.

26.- Composition according to any of the claims 20 to 25, characterized in that it has a water content less than 15% by weight with respect to the overall weight of the compound having general formula (I).

27.- Composition according to any of the claims 20 to 26, characterized in that it comprises a colouring agent.

28.- Composition according to claim 27, characterized in that it contains said colouring agent in a proportion that is less than or equal to 0.5% by weight, preferably less than or equal to 0.4% by weight with respect to the overall weight of the compound having general formula (I).

29.- Composition according to any of the claims 20 to 28, characterized in that it is a mixture of a first compound having general formula (I) with a branch consisting of a functional carboxylic acid group or a-SO₃H group and at least one second compound having general formula (I) with no branch consisting of a functional carboxylic group or -SO₃H group, where said second compound has m and n equal to O.

30.- Composition according to any of the claims 20 to 29, characterized in that the concentration of compounds having general formula (I) is between 50-70% by weight with respect to the total weight of the composition having general formula (I).

31.- Composition according to any of the claims 20 to 29, characterized in that the concentration of compounds having general formula (I) is between 70-90% by weight with respect to the overall weight of the composition having general formula (I)₁ and preferably it is 80%.

32.- Composition according to any of the claims 20 to 31 , characterized in that it comprises, in addition, a volatile amine that forms a salt with said carboxylic acid or -SO₃H, preferably ammonium or triethylamine.

33.- Method for producing a watermark in a cellulosic sheet material, characterized in that it comprises a stage of applying a compound having general formula (I) according to any of the claims 1 to 19, where R, R', X, X', X", A, m, B, and n have the general meaning indicated above, to said cellulosic sheet material by means of flexography.

34.- Method for producing a watermark on a cellulosic sheet material, characterized in that it comprises a stage of applying a composition according to any of the claims 20 to 32 to said cellulosic sheet material by means of flexography.

35.- Method for producing a watermark on a cellulosic sheet material, characterized in that it comprises a stage of applying a compound having general formula (I) according to any of the claims 1 to 19, where R, R', X, X', X", A, m, B, and n have the general meaning indicated above, to said cellulosic sheet material by means of intaglio printing.

36.- Method for producing a watermark on a cellulosic sheet material, characterized in that it comprises a stage of applying a compound having general formula (I) according to any of the claims 1 to 18, where R, R¹, X, X', X", A, m, B₁ and n have the general meaning indicated above, to said cellulosic sheet material by means of offset.

37.- Method for producing a watermark on cellulosic sheet material, characterized in that it comprises a stage of applying a composition according to any of the claims 19 to 31 to said cellulosic sheet material by means of offset.

38.- Use of a composition according to any of the claims 20 to 32, for producing a watermark on a cellulosic sheet material.

39.- Use of a composition according to any of the claims 19 to 31 , for producing a watermark on a cellulosic sheet material.