DE10009754A1 - Printing ink containing olefin polymer produced using metallocene catalyst and additives, useful in offset, intaglio of flexographic printing, has high resistance to abrasion - Google Patents

Abstract

Use, for preparing printing ink, of a mixture of (1) a homo- or co-polymer of 2-18C alpha -olefins produced using a metallocene catalyst (A) or a 'decomposition wax' prepared from long-chain polyolefins, also produced using (A), and (2) one or more of 12 specified additives. The specified additives are: poly(tetrafluoroethylene) (PTFE) of number-average molecular weight (Mn) 30-2000 kD; thermoplastic PTFE of Mn 0.5-10 MD and particle size 1-100 micron; amide waxes, prepared by reacting ammonia or ethylene diamine with (un)saturated fatty acids; montan waxes, including acid or ester waxes with carbon chain length 22-36C; natural plant waxes; reaction products of sorbitol with unsaturated and/or saturated fatty acids and/or montanic acid; synthetic hydrocarbons; paraffin and microcrystalline waxes from crude oil refining; polar polyolefin waxes, prepared by oxidation of ethylene or propylene (co)polymer waxes or by grafting with maleic anhydride; polyamides of particle size 1-100 micron; polyolefins (e.g. polyethylene, polypropylene or their copolymers) of high or low density, with Mn 10-1000 kD and particle size 1-100 micron or agents that reduce the surface tension of liquids (wetting agents).

Description

The present invention relates to the use of means Metallocene catalysts produced polyolefin waxes in combination with PTFE, Amide waxes, montan waxes, natural plant waxes, sorbitol esters, synthetic hydrocarbon waxes, micro and macro crystalline paraffins, polar polyolefin waxes as an additive component in printing inks.

In printing inks, waxes have the task of abrasion, scouring and Increase scratch resistance of printed matter. The waxes are usually in the form of solvent dispersions or pastes or in solid form micronized form used. Micronization occurs either through Grinding on suitable mills or spraying from the melt, in each case if necessary with subsequent classification. The necessary average particle sizes are usually below 10 µm.

To date, waxes of various types have been found for this application Manufacturing process use. It is common - in addition to the thermal degradation of high molecular weight polyolefins or radical ethylene polymerization high pressures and temperatures - the production of waxes by ethylene or propylene homo- or copolymerization with Ziegler-Natta catalysts a titanium compound as a catalytically active species, such as in DE-A-15 20 914 discloses.

EP-A-0 890 619 discloses that in particular the use of Metallocene catalyst systems in the manufacture of polyolefin waxes Materials leads to improved abrasion protection effects when used in printing inks cause.  

The use of pure using metallocene catalysis Polyolefin waxes in printing inks cover the basic requirements for one improved abrasion protection compared to the original printing ink. In addition, there are applications that look for specially improved Abrasion protection or high surface gliding effect or good overprintability request e.g. B. when printing abrasive, matt-coated papers or in Packaging printing area.

Surprisingly, it has now been found that polyolefin waxes are produced using of metallocene catalysts, in combination with additives this increased Meet the requirements profile in a special way.

The present invention relates to the use of mixtures of

• a) polyolefin waxes from C ₂ -C ₁₈ -α-olefins, produced using metallocene catalysts, with one or more further additives, selected from the group consisting of
• b) polytetrafluoroethylene,
• c) amide waxes,
• d) Montan waxes including acid and ester waxes with a carbon chain length of the carboxylic acid from C ₂₂ to C ₃₆
• e) natural plant waxes,
• f) reaction products of sorbitol (sorbitol) with saturated and / or unsaturated fatty acids and / or montanic acids
• g) synthetic hydrocarbons,
• h) paraffins and microcrystalline waxes, which are used in petroleum refining attack,
• i) polar polyolefin waxes, producible by oxidation of ethylene or Propylene homopolymer and copolymer waxes or their grafting with Maleic anhydride

for the production of printing inks.  

Polyolefin waxes a) are homopolymers of ethylene, propylene, Copolymers of ethylene and propylene, or copolymers of ethylene or Propylene with one or more 1-olefins in question. As 1-olefins linear or branched olefins with 4-18 C-atoms, preferably 4-6 C-atoms, used. The 1-olefins can also carry an aromatic substitution. Examples of suitable 1-olefins in addition to ethylene and propylene are 1-butene, 1-hexene, 1-octene or 1-octadecene, also styrene. Are particularly preferred Homopolymers of ethylene or propylene or copolymers of ethylene with Propylene or 1-butene. If they are copolymers, they exist preferably 70-99.9, in particular 80-99% by weight of ethylene.

Such polyolefin waxes with a dropping point between 70 and 165 ° C., in particular between 100 and 160 ° C., a melt viscosity at 140 ° C. (polyethylene waxes) or at 170 ° C. (polypropylene waxes) between 10 and 10,000 mPas, in particular between 50, are particularly preferred and 5000 mPas, and a density at 20 ° C between 0.85 and 0.96 g / cm ³ . Preferred polyolefin waxes have a molecular weight distribution M _w / M _n <5.

In preferred embodiments, additive b) is Polytetrafluoroethylene with a molecular weight between 30,000 and 2,000,000 g / mol, in particular between 100,000 and 1,000,000 g / mol.

In preferred embodiments, additive c) is Amide waxes, producible by reacting ammonia or ethylenediamine with saturated and / or unsaturated fatty acids. The fatty acids are for example, stearic acid, tallow fatty acid, palmitic acid or erucic acid.

Additive d) is montan waxes including acid and ester waxes with a carbon chain length of the carboxylic acid from C ₂₂ to C ₃₆ . The ester waxes are preferably reaction products of montanic acids with mono- or polyhydric alcohols having 2 to 6 carbon atoms, such as, for example, ethanediol, butane-1,3-diol or propane-1,2,3-triol.

In a preferred embodiment, additive e) is Carnauba wax.

In preferred embodiments, additive f) is Reaction products of sorbitol (sorbitol) with saturated and / or unsaturated Fatty acids and / or montanic acids. The fatty acids are Examples include stearic acid, tallow fatty acid, palmitic acid or erucic acid.

In preferred embodiments, additive g) is fishing Tropsch waxes.

Additive h) is paraffins and microcrystalline waxes, which incurred in oil refining. The dropping points of such paraffins are located preferably between 48 and 65 ° C, that of such microcrystalline waxes preferably between 75 and 95 ° C.

In preferred embodiments, additive i) is polar polyolefin waxes, which can be prepared by oxidation of ethylene or propylene homopolymer and copolymer waxes or their grafting with maleic anhydride. Polyolefin waxes with a dropping point between 90 and 165 ° C., in particular between 100 and 160 ° C., a melt viscosity at 140 ° C. (polyethylene waxes) or at 170 ° C. (polypropylene waxes) between 10 and 10,000 mPas, in particular between, are particularly preferred for this purpose 50 and 5000 mPas and a density at 20 ° C between 0.85 and 0.96 g / cm ³ .

The mixing ratio of component a) to components b) to i) can in Range can be varied from 1 to 99 wt .-% a) to 1 to 99 wt .-% b) to i). Becomes If a mixture of several of the components b) to i) is used, the Quantity specification for the sum of the quantities of these components.

In a preferred embodiment, the waxes are in micronized form used for the purpose of the invention.  

The metallocene catalysts for the preparation of the polyolefin waxes are chiral or nonchiral transition metal compounds of the formula M ¹ L _x . The transition metal compound M ¹ L _x contains at least one metal central atom M ¹ to which at least one π ligand, e.g. B. a cyclopentadienyl ligand is bound. In addition, substituents such. B. halogen, alkyl, alkoxy or aryl groups to the metal central atom M ¹ . M ¹ is preferably an element of III., IV., V. or VI. Main group of the periodic table of the elements, such as Ti, Zr or Hf. Cyclopentadienyl ligand is understood to mean unsubstituted cyclopentadienyl radicals and substituted cyclopentadienyl radicals such as methylcyclopentadienyl, indenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl, tetrahydroindenyl or octa-tetra-hydrofluoryl or octa-tetra-hydrofluoryl or octa. The it ligands can be bridged or unbridged, whereby single and multiple bridging - also via ring systems - are possible. The term metallocene also includes compounds with more than one metallocene fragment, so-called multinuclear metallocenes. These can have any substitution pattern and bridging variant. The individual metallocene fragments of such multinuclear metallocenes can be of the same type or different from one another. Examples of such multinuclear metallocenes are e.g. B. described in EP-A-0 632 063.

Examples of general structural formulas of metallocenes, as well as for their Activation with a cocatalyst are u. a. in EP-A-0 571 882.

The polyolefin waxes from metallocene catalysis are as follows Component 1 called, the additives b) to i) are component 2. The proportion of Component 2 in the mixture with component 1 can be between 1 to 99% amount, preferably between 5 to 50%. Mixtures can be made by grinding the two components together or by previous Mixing the components in the molten phase and subsequent Spraying or grinding.  

Examples

Table 1

Physical properties of the tested polyolefin waxes

On the basis of wax 1 and 2 and comparative wax 1, the following were: Mixtures made:

Table 2

Mixtures of polyolefin waxes with additives

The powdery starting materials were used to prepare the mixtures first premixed and then on a fluid bed counter jet mill Hosokawa Alpine AG to an average particle size below 10 microns crushed. The particle size is measured with the Laser diffraction method in a Malvern device. You can use the waxes the printing ink as a dry powder or preferably as a dispersion in Add binder solution or solvent.

Examples of ink production 1) Offset color

The mixtures M1, M2, M3, M4, M9 and M10 were incorporated in an offset ink (Novaboard® Cyan 4 C 86, BASF Drucksyseme GmbH) at 1.5% by weight with intensive stirring with a dissolver and subsequent homogenization on a three-roller . A test print (Prüfbau multi-purpose test printing machine System Dr. Dürner) was made on Phoenomatt® 115 g / m ² paper (Scheufelen GmbH + Co KG) and the abrasion behavior was examined on a scrubber tester (scrubbing tester Prüfbau Quartant) with a scouring load of 48 g / cm ² , scrubbing speed 15 cm / sec. The intensity of the color transferred to the test sheet after 50, 100 or 200 abrasion cycles (stroke) (color difference according to DIN 6174, measurement with Hunterlab D 25-2, Hunter) and the damage to the printed image were assessed.

Table 3

Result of the test in an offset color when incorporated as micropowder

The waxes according to the invention bring about a smaller color difference and thus improved abrasion resistance.

2) gravure ink

The mixtures M3, M4, M5, M6, M7 and M5 were incorporated at 1% by weight with intensive stirring with a dissolver into an illustration gravure ink (type RR Grav rot, Siegwerk Farbenfabrik). A test print (gravure test printer LTG 20, Einlehner testing machine construction) was made on Allgäu 60 g / m ² paper (G. Haindl'sche Papierfabriken KG) and tested according to the example of offset ink.

Table 4

Result of the test in a gravure ink when incorporated as micropowder

The waxes according to the invention bring about a smaller color difference and thus improved abrasion resistance. Surprisingly, there has also been one Lower sliding friction with addition of sorbitan esters shown.

3) Flexographic printing ink

The mixtures M3, M4, M5, M6, M7, M8, M11 and M12 were incorporated at 1% by weight into an aqueous flexographic printing ink with intensive stirring using a dissolver. The flexographic printing ink is composed of 35% by weight of Synthacryl® SW 175, 20% by weight of Hostapermblau® B2 G, 45% by weight of water. The ink was made with a wire doctor blade with a wet film thickness of 6 µm on Allgäu 80 g / m ² paper (G. Haindl'sche Papierfabriken KG) and tested according to the example of offset ink.

Table 5

Result of the test in a flexographic printing ink when incorporated as micropowder

The waxes according to the invention bring about a smaller color difference and thus improved abrasion resistance. Surprisingly, there has also been one Lower sliding friction with addition of sorbitan esters shown.

Claims (8)

1. Use of mixtures of

• a) polyolefin waxes from C ₂ -C ₁₈ -α-olefins, produced using metallocene catalysts, with one or more further additives selected from the group consisting of
• b) polytetrafluoroethylene,
• c) amide waxes,
• d) montan waxes including acid and ester waxes with a carbon chain length of the carboxylic acid from C ₂₂ to C ₃₆ ,
• e) natural plant waxes,
• f) reaction products of sorbitol (sorbitol) with saturated and / or unsaturated fatty acids and / or montanic acids,
• g) synthetic hydrocarbons,
• h) paraffins and microcrystalline waxes, which are obtained from petroleum refining
• i) polar polyolefin waxes, producible by oxidation of ethylene or propylene homopolymer and copolymer waxes or their grafting with maleic anhydride

for the production of printing inks. 2. Use according to claim 1, wherein component a) is an ethylene homo- or Is copolymer wax. 3. Use according to claim 1, wherein component a) is a propylene homo- or Is copolymer wax. 4. Use according to one or more of claims 1 to 3, wherein the Polyolefin waxes of component a) a molecular weight distribution Mw / Mn <5 exhibit. 5. Use according to one or more of claims 1 to 4, wherein the Polyolefin waxes have a melt viscosity of 5 to 100,000 mPas.   6. Use according to one or more of claims 1 to 5, wherein the Polyolefin waxes have a dropping point of 70 to 165 ° C. 7. Use according to one or more of claims 1 to 6, wherein the Proportion of the additive (s) 1-99% by weight based on the Total mass of the mixture is. 8. Use according to one or more of claims 1 to 7, wherein the Waxes can be used in micronized form.