DE10059397A1 - Ink composition for e.g. marker pens, fine-liners, and needle points, comprises an antidrying additive comprising esters of alcohols with carboxylic acids, alkyl alcohols having at least 10C atoms and/or polyethers and their copolymers. - Google Patents

Abstract

Ink composition (I) comprises an antidrying additive comprising esters of mono, di- or trivalent alcohols with carboxylic acids, linear and/or branched alkyl alcohols having at least 10C atoms and/or polyethers and their copolymers whereby (D) has a dynamic viscosity of 8-600 mPas (40 deg C) and only a partial solubility in the solvent or solvent mixture and does not crystallize out. Ink composition (I) comprises (wt.%): (A) an organic solvent (59-93.5) having a boiling point of 60-180 deg C and/or water (B) resin (3-6); (C) dye and/or pigment (4-15); (D) an antidrying additive (0.5-20) comprising esters of mono, di- or trivalent alcohols with carboxylic acids, linear and/or branched alkyl alcohols having at least 10C atoms and/or polyethers and their copolymers whereby (D) has a dynamic viscosity of 8-600 mPas (40 deg C) and only a partial solubility in the solvent or solvent mixture and does not crystallize out. Independent claims are also included for the following: (1) a writing instrument containing the ink composition (I); and (2) the use of esters of mono-, di- or trivalent alcohols with carboxylic acids, linear and/or branched alkyl alcohols having at least 10C atoms and/or polyethers and their copolymers as an antidrying agent, comprises: (i) an organic solvent (59-93.5); (ii) a resin (3-6); and (iii) a dye and/or a dye pigment (4-15).

Description

The invention relates to an ink composition based on volatile solvents, especially for Schreibge is suitable and against drying out of an exposed Writing tip or outlet opening of a writing instrument Additives includes.

It is known that the writing tips or exit openings of fineliner, needle point or rollerball devices as well Marking pens with a porous fiber tip and the like (follow generally referred to as "writing instruments") quickly dry up Can, if not with a sealing cap be stored. In particular inks, inks, printing inks, Marking fluids and the like (hereinafter generally referred to as "Ink Compositions" means the volatile Contain solvent, dry in the capillary outlet as the volatile components on the open vaporizing capillary openings. This will  on the one hand the outlet openings through dispersed solids (e.g. color pigments or resins) clogged more quickly, and others on the one hand, the surface tension and viscosity of the inks become composition increased. This leads to shouting again ben the unimpeded flow of the ink composition from the capillary outlet openings of the writing tip is disturbed what the quality of the recorded line (e.g. edge sharpness) decreases. Only by continuing the re-running writing process can be done with the emerging inks create acceptable records again. in the Extreme case of a very long storage without protective and thinning Anti-slip closure, the ink composition can be such dry up that a re-letter no longer at all is possible.

A number of methods have therefore been developed to do this Evaporation of solvent from an open, unprotected and to prevent unused writing tip.

For example, the ink composition can be made less volatile Solvents (i.e. high boiling point and low vapor pressure) add, which makes even more volatile after evaporation Components of the composition still rewrite is possible. The use of low volatile solvents in ink compositions, however, has the disadvantage that these poor on non-absorbent writing pads (e.g. foils) dry. In addition, with increasing exposure time the Desired quality of the recorded line when writing to it can no longer be reached because of evaporation of volatile fractions together the viscosity of the inks has changed.

Another method to prevent dehydration exposed nibs is to close the inks add crystallizing solids to the composition  Verdun the surface of the writing tip or outlet can form a protective layer that inhibits

For example, EP-B-0 359 805 discloses the use of solids crystallizing in a certain way as an antiblock additive in usual marking liquids for writing instruments capillary outlet. These solids are in the Solvent or solvent mixture soluble, have one Melting point ≧ 30 ° C and a molecular weight of 1000 daltons and are able from the solvent or solvent mixture at the capillary outlet opening with the formation of growing To crystallize crystallites, provided the solvent or Solvent mixture no dye or pigment, none usual additive and also contains no high boilers or as pure Mix is present. By forming the crystalline border layer is the open shelf life of the with the invention used anti-blocking additive to transfer marking liquids increased by at least a factor of 2. As examples of such feast substances are inorganic salts, organic acids and their Derivatives, amino acids and their derivatives, iso-, poly- or heterocyclic compounds and their derivatives, urea and their derivatives or sulfur compounds called.

The use of the above crystallizing solids has the disadvantage, however, that the ratio between solid and dye or resin, both for gluing the capillaries Exit openings can lead to each other within narrow limits must be matched to a blooming crystal at the same time to avoid lit formation, best possible open storage to achieve and create a soft boundary layer that holds as many liquid molecules as possible in the crystal composite and immediately tears open when you write to me. Furthermore, such Also crystallize solids in the recorded line. This leads to the fact that on smooth writing pads (e.g. Overhead transparencies) black lines appear matte and gray and colored lines do not have the usual brilliance.  

Also in US-A-4,525,216 is an ink composition described, which comprises an anti-drying additive, that is deposited on the surface of a writing tip and there forms a thin solid film if only a small amount of solvent near the tip surface evaporated. This additive is selected from the group of certain glycerides, alkyl amide alcohols and sorbitan fatty acid esters is soluble in the solvent of the ink composition and preferably solid or semi-solid at normal temperatures.

There is a disadvantage of such film-forming substances in that the film only partially changes when rewritten difficult to break open. The mechanism to prevent the Drying out of an exposed writing tip is furthermore susceptible to malfunction, because only then can an optimal protective effect be achieved when the film is completely closed.

The object of the present invention is therefore the above to avoid listed disadvantages of the prior art and to provide an improved ink composition that also after a long tip of a writing tip or exit opening of writing instruments does not dry out when re-writing process is easy to write off and a line of high quality (Gloss, edge sharpness) on any surface.

This object is achieved by an ink composition based on its final composition

• a) 59-93.5 wt .-% organic solvent with a Boiling point in the range of 60 ° C to 180 ° C and / or what ser,
• b) 3-6% by weight of resin,
• c) 4-15% by weight of dye and / or color pigment,
• d) 0.5-20% by weight of additive which acts against drying out of an exposed writing tip or outlet opening of a writing instrument and is selected from
  • Esters of mono-, di- and trihydric alcohols with carboxylic acids,
  • - Linear and / or branched alkyl alcohols with at least 10 carbon atoms and / or
  • Polyethers and their copolymers,

wherein the additive (d) has a dynamic viscosity (40 ° C), in Range from 8 to 600 mP.s an only partial solubility in the Has solvent or solvent mixture and not from it crystallized.

According to the invention, the ink composition comprises, based on their final composition, 59 to 93.5% by weight, preferably 65 up to 90 wt .-% and in particular 70 to 85 wt .-% organic Solvent (a) and / or water, with a mass fraction of 75 to 80% by weight is most preferred.

According to the invention, the organic solvent has a boiling point in the range from 60 ° C. to 180 ° C., preferably in the range from 70 ° C to 170 ° C and in particular in the range from 90 ° C to 120 ° C, a range of 95 ° C to 100 ° C is most preferred.

The organic solvents (a) mentioned are solution commonly used in ink compositions medium. These are, for example: methanol, ethanol, 1-propanol, 2-propanol (isopropyl alcohol), 1-butanol, 2-butanol, 2-methyl-2- propanol (tert-butyl alcohol), 2-methyl-1-propanol (isobutylal alcohol), dimethylformamide, dimethylacetamide, ethyl methyl ketone, Diacetone alcohol, tetrahydrofuran, dioxane, toluene, xylene, tri chloroethane and tetrachlorethylene. 1-propanol, 1-butanol, diaceto alcohol or mixtures thereof are most preferred.

According to the invention, the ink composition further comprises based on their final composition, 3 to 6 wt .-%, preferably 3.5 to 5.5% by weight and in particular 4.0 to 4.8% by weight of resin (b), with a mass fraction of 4.4 to 4.8% by weight most  is preferred. Each can be in ink compositions usual synthetic resin (synthetic resin), natural resin or their modified forms are used, which in the solvent or Solvent mixture is soluble or dispersible.

Acrylic resins, styrene copolymers (e.g. Suprapal® AP 20, Suprapal® AP 30, BASF), ketone resins (e.g. Bremar® 7080, Kraemer), maleinate resins (e.g. Erkamar® 3300, Kraemer), Polyvinyl butyral resins (e.g. Mowital® B 30 T, Clariant) and Shellac used as a natural resin.

According to the invention, the ink composition further comprises based on their final composition, 4 to 15 wt .-%, preferred example 6 to 13 wt .-% and in particular 8 to 11 wt .-% dye and / or color pigment (c), a range from 9 to 10% by weight is most preferred. Any of these can occur Ink compositions customary inorganic or organic Dyes and / or pigments synthetic or natural Origin are used. This is not only in the solution medium or solvent mixture soluble dyes but also Color pigments meant in the ink composition in dispersed form. Suitable dyes or colors Pigments include: Solvent Brown 52 & Solvent Violet 9 (e.g. Morfast Black 108, Morton), Solvent Black 48 (e.g. Morfast Black 101, Morton), Solvent Yellow 79 (e.g. Savinyl Yellow 2GLS, Clariant), Solvent Orange 25 (e.g. Sepisol Fast Orange GRL, BIMA), Solvent Red 109 (e.g. Neozapon Rot 346, BASF), Solvent Blue 70 (e.g. Neopen Blau 807, BASF), Basic Violet 11: 1 (e.g. Basonyl Red 560, BASF), Solvent Blue 44 (e.g. Savinyl Blue GLS, Clariant), Basic Blue 7 (Basonyl Blue 636, BASF), solvent Red 127 (Savinyl Pink 6BLS, Clariant), Pigment Yellow 17 (e.g. Renol Yellow GG-HW, Clariant), Pigment Red 112 (e.g. Renol Red FGR- HW, Clariant), Pigment Violet 23 (e.g. Renol Violett RL-HW, Clariant), Pigment Blue 15: 3 (e.g. Renol Blau B2G-HW, Clariant), Pigment Green 7 (e.g. Renol Grün GG-HW, Clariant) and pigment Black 7 (e.g. Renol Schwarz R-HW, Clariant).  

The ink composition further contains, based on its end composition, an anti-drying additive (d) in an amount of 0.5 to 20% by weight, preferably 5 to 15% by weight and especially 7 to 13% by weight, with a range of 9 to 11% by weight is most preferred.

The additive that works against drying out is also referred to below as "Cap-off additive" or referred to as an "additive".

According to the invention, the anti-drying additive has a dynamic viscosity (40 ° C) in the range of 8 to 600 mPa.s, only a partial solubility in the solvent or Solvent mixture, which makes it when using these additives does not lead to crystallite formation on the surface of a open, unused nib or exit opening A writing instrument comes when volatile components evaporate the ink composition there.

In general, the following can be used as cap-off additives:

• - Esters of mono-, di- and trihydric alcohols with Carboxylic acids;
• - linear and / or branched alkyl alcohols with at least 10 Carbon atoms and / or
• - Polyethers and their copolymers.

Preferred cap-off additives are:

• - Esters of linear and / or branched alkyl alcohols with 8 to 17 carbon atoms with carboxylic acids,
• Esters of mono- or diglycerol with fatty acids,
• - linear or branched alkyl alcohols with 11 to 17 carbons atoms of matter, as well
• - polyethylene oxides, polypropylene oxides and / or ethylene oxide / Propylene oxide copolymers.

In particular, the esters have linear and / or branched ones Alkyl alcohols with 8 to 17 carbon atoms with carboxylic acids as well as the esters of mono- or diglycerol with fatty acids Solubility in ethanol at 25 ° C in the range of 4 to 13% by weight and have an oily, honey-like or waxy at 20 ° C Consistency.

Particularly preferred cap-off additives: myristyl myristate, My ristyl lactate, (e.g. Ceraphyl® 50, ISP), adipic acid up to 2- ethylhexyl ester (dioctyl adipate; e.g. Rilanit® DOA, Henkel), mixed triglyceride of fatty acids with 10 to 18 carbon atoms (currently, for example, under the trade name Softisan® 134 from Condea Chemie GmbH, Witten, available), mixed ester of Diglycerins with caprylic, capric, isostearic and adipic acids (e.g. Softisan® 649, Condea), mixed triglyceride with caprylic, Capric and stearic acid (e.g. Softisan® 378, Condea) and Ethylene oxide / propylene oxide block copolymers.

Among the ethylene oxide / propylene oxide block copolymers are those most preferred which is either a central polypropylene oxide block with a molecular weight of 850 to 3250 g / mol at a Total molar mass from 1000 to 4600 g / mol or a central one Polyethylene oxide block with a molecular weight of 400 to 600 g / mol have a total molar mass of 3100 to 3650 g / mol. at such connections are currently among the Trade names Pluronic® PE and Pluronic® RPE 2520 and RPE 3110 (BASF AG, Ludwigshafen) available.

Are the cap-off additives mentioned in the invention Ink composition used, it is believed that it Loss of solvent a soft, highly viscous barrier layer on the Surface of the writing tip or exit opening of a Form writing instrument or a printing device, whereby increased open lay time, improved writability and quality of the recorded line is achieved. by virtue of their limited solubility in the solvent or solvent mixture  the additives mentioned show the tendency to turn on the surface of a writing tip or outlet, ins especially when solvents evaporate. By the relatively high viscosity of the cap-off additives an effective barrier layer is formed, the mobility of Solvent molecules in this and through this layer strong reduced. However, the additives mentioned do not lead to any Crystallite formation still to form a solid film. Thereby the rewrite is improved because the barrier layer can break open with very little pressure and the afterflow of underlying "original" ink composition can be practically trouble-free.

The ink composition according to the invention can already be used in addition to the mentioned components other, usually used in inks te additives include. These include, for example, Disper yaws, binders, pH regulators, anti-corrosion agents, Preservatives, fungicides, surfactants, defoamers, shine medium and other additional aids.

The ink composition of the present invention can be produced be by the individual components in any order ge, preferably solvent or water being introduced, be mixed together. The pigment is usually called Pigment concentrate added. It is preferred to start with one Dissolver made a rough predispersion by using the over most of the solvent or water is used. The predispersed mixture is then in a bead mill finely dispersed and the remaining solvent or water added. It continues to disperse until again has a homogeneous distribution.

The ink composition according to the invention can be used in writing utensils such as marking pens with a correspondingly porous fiber tip and in Fineliner, needle point, rollerball equipment and overhead pens be used.  

Writing implements containing the ink composition of the invention included, write on absorbent (e.g. paper) and not absorbent surfaces (e.g. plastic film, glass, metal), whereby glossy drying, smudge-proof lines with high edge sharpness be generated.

The following examples illustrate the present invention.

Examples

Ink compositions according to the invention were produced which basically had the following basic recipe:

example 1 (Ink, black)

In accordance with the basic recipe above, a base ink was first produced in which Bremar 7080 resin and Morfast Black 108 dye were used and had the following composition:

Various inks were added using this base ink compositions produced, the (100 - x) wt .-% of this ink and as a cap-off additive Softisan® 649 in a concentration of x% by weight, the concentrations of Softisan® 649 0, 2, 5, 7.5 and 10 wt .-% were.

These ink compositions were made in terms of writing quality lity of the recorded line and the mass loss in Dependence on the open time (after 1 h, 3 h, 24 h, 72 h and 168 h) of the writing instrument.

Fig. 1 shows the writing quality after various open times (after 1 h, 3 h, 24 h, 72 h and 168 h) for the ink compositions prepared from the basic ink (black), in which Softisan® 649 is used as a cap-off additive has been. The writing quality of the recorded line was rated on a relative scale from "+3" to "-3", where "+3" is an even, saturated line, "0" a pale but still acceptable line and "-3" not means more line to be created. It can be seen from FIG. 1 that the addition of the Softisan® 649 cap-off additive achieves a significantly improved writing quality even after the writing tip has been open for a long time. For comparison, the writing quality of the ink compositions described was also tested with the writing instrument's cap closed. The minimum concentration of Softisan® 649, which was required to reach a still acceptable line after an exposure time of 1 h, was about 2% by weight. In order to obtain acceptable lines after longer exposure times of up to 72 h, Softisan® 649 must be used in a minimum concentration of 5% by weight.

Fig. 2 shows the mass loss of the base ink (black) of the ink compositions produced, in which Softisan® 649 was used as a cap-off additive, as a function of the open time of the writing instrument. It can be seen from this that by adding Softisan® 649 in a concentration of 2% by weight, the mass loss of the ink composition can be significantly reduced compared to ink compositions in which no Softisan® 649 was present. Even with a minimum concentration of Softisan® 649 of 2% by weight, the mass loss after an exposure time of 1 hour could be significantly reduced compared to an ink composition without a cap-off additive.

Example 2 (Ink, blue)

A basic ink was produced according to the basic recipe above, in which Bremar 7080 resin and Savinyl Blau GLS and Savinyl Rosa 6BLS dyes were used and had the following composition:

Various inks were added using this base ink compositions produced, the (100 - x) wt .-% of this ink and as a cap-off additive Softisan® 649 in a concentration of x% by weight, the concentrations of Softisan® 649 0, 2, 5, 7.5 and 10 wt .-% were.

As already mentioned above, these ink compositions were regarding the writing quality of the recorded line as well of the mass loss depending on the open time of the Nib tested.

Fig. 3 shows the writing quality after various open times (after 1 h, 3 h, 24 h, 72 h and 168 h) for the ink compositions prepared, in which Softisan® 649 was used as a cap-off additive. The minimum concentration required to achieve a uniform, full line after an open period of 24 hours was about 2% by weight. As a comparison, the writing quality of the above-mentioned ink compositions was again tested even when the writing instrument's cap was closed.

FIG. 4 shows the mass loss of the ink compositions produced from the basic ink (blue), in which Softisan® 649 was used as a cap-off additive, as a function of the exposure time. It can be seen from FIG. 4 that a minimum concentration of Softisan 649 of 2% by weight of the masses significantly reduces the ink composition after an exposure time of 30 minutes compared to ink compositions in which Softisan® 649 was not present has been.

Test Methods

For checking the writing quality of the recorded line after various periods of exposure, writing instruments were used Fiber storage and fiber tip in line width F (fine) used that filled with the ink compositions mentioned were. The filled writing utensils were closed with Cap stored for about 1 hour, then on an overhead project scoreboard with 3 lines each about 15 cm long and then stored horizontally without a cap. After test intervals of The writing utensils became 1 h, 3 h, 24 h, 72 h and 168 h again written with 3 lines on overhead projector film and thereby judged the line quality. Before examining each subsequent intervals, the writing utensils were through Storage with closed cap or exchange in the exit condition, written again and then without cap stored horizontally. As already described, the Assessment of the writing quality of the recorded line based on a scale from "+3" to "-3" with the corresponding Ab gradations in between.

To contribute to the mass loss of said ink compositions exposed writing tip due to evaporation depending writing utensils were used to check the open time Fiber storage and fiber tip in line width F (fine) with each filled 2.8 g of the ink compositions mentioned. The Writing utensils were stored for approx. 1 h with the cap closed, then on copier paper with 3 lines each about 15 cm long written on and then without cap on an analytical balance (Resolution 0.0001 g) stored horizontally  (Resolution 0.0001 g) stored horizontally Initial mass of the unlocked writing instrument was measured. After test intervals of 0.5 h, 1 h, 1.5 h, 2.5 h, 3.5 h and 6 h the mass of the unlocked writing instrument became again measured. The mass loss was calculated as a percentage the total mass of the ink composition filled.

Both checking the writing quality of the recorded line as well as checking the mass loss of the inks at a temperature of approx. 23 ° C and at a relative Humidity of about 60% carried out.

Claims (14)

1. Ink composition based on its final composition

• a) 59-93.5% by weight of organic solvent with a boiling point in the range from 60 ° C. to 180 ° C. and / or water,
• b) 3-6% by weight of resin,
• c) 4-15% by weight of dye and / or color pigment,
• d) 0.5-20% by weight of an additive which acts against drying out of an exposed writing tip or outlet opening of a writing instrument and is selected from

• Esters of mono-, di- and trihydric alcohols with carboxylic acids,
• - Linear and / or branched alkyl alcohols with at least 10 carbon atoms and / or
• Polyethers and their copolymers,

the additive (d) has a dynamic viscosity (40 ° C.) in the range from 8 to 600 mPa.s, only a partial solubility in the solvent or solvent mixture and does not crystallize therefrom. 2. Ink composition according to claim 1, characterized in net that the carboxylic acid ester is an ester of linear and / or branched alkyl alcohols with 8 to 17 carbons atoms with carboxylic acids and / or an ester of mono- or diglycerin with fatty acids. 3. Ink composition according to claim 2, characterized records that the ester of linear and / or branched Alkyl alcohols with 8 to 17 carbon atoms with carboxylic acid ren and / or the ester of mono- or diglycerol with fat Acids solubility in ethanol at 25 ° C in the range of Has 4 to 13 wt .-%.   4. Ink composition according to claim 3, characterized in net that the carboxylic acid ester myristyl myristate, myristyl lactate, adipic acid bis-2-ethylhexyl ester, a mixed Triglyceride of fatty acids with 10 to 18 carbon atoms, a mixed ester of diglycerol with caprylic, capric, Isostearic and adipic acid and / or a mixed one Triglyceride with caprylic, capric and stearic acid. 5. Ink composition according to one of the preceding an sayings, characterized in that the linear or branched alkyl alcohol has 11 to 17 carbon atoms has. 6. Ink composition according to claim 5, characterized in net that the linear or branched alkyl alcohol Myris is alcohol. 7. Ink composition according to one of the preceding an sayings, characterized in that the polyether or the Polyether copolymer polyethylene oxide, polypropylene oxide and / or an ethylene oxide / propylene oxide copolymer. 8. Ink composition according to claim 7, characterized in net that the ethylene oxide / propylene oxide copolymer Is ethylene oxide / propylene oxide block copolymer. 9. Ink composition according to one of the preceding an sayings, characterized in that the ethylene oxide / Propylene oxide block copolymer a central polypropy lenoxide block with a molecular weight of 850 to 3250 g / mol and has a total molar mass of 1000 to 4600 g / mol. 10. Ink composition according to one of the preceding An sayings, characterized in that the ethylene oxide / propylene oxide block copolymer a central polyethylene oxide block  with a molecular weight of 400 to 600 g / mol and has a total molar mass of 3100 to 3650 g / mol. 11. Use of esters of mono-, di- and trihydric alcohols with carboxylic acids, of linear and / or branched alkyl alcohols with at least 10 carbon atoms and / or of polyethers and their copolymers, as against drying out of an exposed writing tip or from the opening of a writing instrument acting additive in an ink composition based on its final composition

• a) 59-93.5% by weight of organic solvent with a boiling point in the range from 60 ° C. to 180 ° C. and / or water,
• b) 3-6% by weight of resin and
• c) comprises 4-15% by weight of dye and / or color pigment,

wherein the additive mentioned has a dynamic viscosity (40 ° C.) in the range from 8 to 600 mP.s, only partial solubility in the solvent or solvent mixture and does not crystallize therefrom. 12. Writing implement, characterized in that there is an ink contains composition according to any one of claims 1 to 10. 13. Writing implement according to claim 12, characterized in that it is a marker, a fineliner, needle point, roller ball device or an overhead pen. 14. Use of the ink composition according to any one of the An say 1 to 10 in a marker pen, a fineliner, Needlepoint, rollerball or an overhead pen.