Title of Invention	"PRINTING INK OR VARNISH FOR FOOD PACKAGING OR DEVICES WHICH COME IN CONTACT OF FOOD"
Abstract	In order to provide a printing ink or a printing varnish for food packaging or contact devices which can come into contact with food, comprising a binding agent with a resin component and a solvent component, which can be used in a simple manner, it is suggested that the solvent component of the varnish be a saturated solvent for resin with one or more components, wherein the solvent or the components of the solvent are a food or a food additive.

Title of Invention

"PRINTING INK OR VARNISH FOR FOOD PACKAGING OR DEVICES WHICH COME IN CONTACT OF FOOD"

Abstract

In order to provide a printing ink or a printing varnish for food packaging or contact devices which can come into contact with food, comprising a binding agent with a resin component and a solvent component, which can be used in a simple manner, it is suggested that the solvent component of the varnish be a saturated solvent for resin with one or more components, wherein the solvent or the components of the solvent are a food or a food additive.

Full Text	Printing Ink or Printing Varnish for Food Packaging or for Contact Devices which can come into Contact with Food The invention relates to a printing ink or a printing varnish for food packaging or for contact devices which can come into contact with food, comprising a binding agent with a resin component and a solvent component. In the case of food packaging, a difference is made, as a rule, between primary packaging and secondary packaging. In the case of primary packaging, an outer side of the packaging is normally printed on and the food which is accommodated in the packaging touches an inner side of the packaging located opposite the oute.r side. In the case of secondary packaging, the food is accommodated in an additional wrapping which is positioned in a packaging printed, irn particular, on the outer side. Examples for contact devices, which can come into contact with food and can, in particular, come into direct contact, are liners in food packaging or bases for foodstuffs, such as trays. Printing ink/printing varnish components can, in principle, pass through the packaging to the food, in particular, in the case of primary packaging. In EP 0 886 671 Bl, an offset printimg ink is described which comprises a colophony modified phenolic resin and/or a maleic resin and/or a modified hydrocarbon resin and/or a colophony resin ester. This offset printing ink has as solvent for the resin/resins one or more water-insoluble fatty acid esters of polyvalent alcohols with high steric spatial requirements and/or of ethinols, wherein the esters have steric measurements of the diameter of 2.0 to 7.0 nm and of the volume of 1.0 to 21.0 nm3. This offset printing ink is described low-migration, low-odor and low-swelling. In the article "Spinat - und nur Spinat!" (Spinach - and only Spinach) of Klaus-Peter Nicolay in Druckmarkt 40, February 2006, pages 30 - 32, low-migration printing inks with the designation MGA of the ink manufacturer Huber are described. These dry non-oxidatively and are absorbed slowly. An inline varnishing with dispersion varnish is required. In the Technical Information 10.1.15/11.2006/Packaging Printing/Offset Printing "MGA-CORONA® 5045" of the huber group, low-migration, organoleptically neutral sheet-fed offset inks are likewise described for the production of food packaging. These printing inks exclusively contain components with a minimum migration potential in order to prevent any undesired interaction of the printing ink with packaged foodstuffs as far as possible. These printing inks dry non-oxidatively and are absorbed relatively slowly; an inline varnishing with dispersion varnish is required. Printing stocks with a low suction capacity require the use of special dispersion varnishes. Dispensing with any inline varnishing results in a lay-up in the stack and the required abrasion resistance will not be achieved. A printing ink on the basis of soy oil is known from US 5,178,672. An edible ink for an ink jet printer is mentioned in US 2004/0086603. An offset printing ink is known from DE 102 09 013 Al which comprises color pigments and a binding agent for the color pigments, wherein the binding agent comprises at least one epoxidized organic component. The object underlying the invention is to provide a printing ink and a printing varnish for food packaging of the type specified at the outset which can be used in a simple manner. This object is accomplished in accordance with the invention, in the printing ink'specified at the outset or the printing varnish specified at the outset, in that the solvent component of the binding agent is a saturated one or more component solvent for resin, wherein the solvent or the components of the solvent are a food or a food additive. The binding agent consists of a resin component (with one or more resins) and a solvent component for dissolving the resin. In the case of printing inks, a binding agent for the pigments which is prepared for the production of printing inks is also designated as varnish. In accordance with the invention, the solvent component of the binding agent is a saturated solvent for the resin with a single component or multiple components, wherein the solvent (when it has one component) or the components of the solvent (when the solvent has several components) are a food or a food additive. As a result of the use of the saturated solvent component of the printing ink or of the printing varnish, the chemical drying and, in particular, oxidative drying of the printing ink/the printing varnish is prevented during/after the printing. No breakdown products result (due to oxidative splitting of multiple bonds) which can migrate to the packaged goods which are accommodated in a packaging which is printed on accordingly. Such breakdown products can, in principle, also transfer into a gaseous phase and cause an odor impairment and swelling. In the case of the solution according to the invention, they are prevented as far as possible. When the solvent component consists of an authorized food (of one component or several components) or of an authorized food additive of one component or several components, a migration of solvent-components into the food is not harmful. When the food or the food additive is selected so as to be organoleptically neutral, there is no deterioration in the quality of the food which is accommodated in the food packaging printed with the corresponding printing ink or the corresponding printing varnish. A food is defined according to Sec. 2 para. 2 of the German Laws on Food and Feed as a food within the meaning of Article 2 of the Regulation (EC) No. 178/2002. According to this Regulation, foods are all substances or products which are intended to be or are reasonably expected to be ingested by humans in a processed, partially processed or unprocessed state. According to Sec. 2, para. 3 of the German Laws on Food and Feed, food additives are substances with or without nutritional value which are, as a rule, not eaten themselves as food nor used as a characteristic ingredient of food and which are added to food for technological reasons during production or processing, whereby they themselves or their breakdown or reaction products will or can become a component of the food directly or indirectly. As a result of the solution according to the invention, printing inks/printing varnishes are provided which are easy to process. Varnishing over is not absolutely necessary. A harmful contamination of food does not take place since the contaminating product is itself a food or authorized food additive. A migration is, therefore, also allowed to a certain extent. As a result, the printing ink/the printing varnish can dry by way of absorption. The printing inks/printing varnishes according to the invention are realized, for example, as offset printing inks/printing varnishes and, in particular, as sheet-fed offset printing inks/printing varnishes. In particular, no cross-linking of the chemical components takes plac. in the case of th printing ink according to the invention and the printing varnish according to the invention. No double bonds, which lead to filming over, are then required in the solvent and/or the resin. In the case of known printing inks which dry oxidatively, resin and/or solvent oil film over on account of double bonds whilst absorbing atmospheric oxygen, initiated by metal components, such as, for example, cobalt salts and/or manganese salts. As described in DE 102 09 013 Al, the formation of a film can also be achieved by using at least one epoxidized component instead of via oxidative drying, wherein the unlocking of the at least one epoxidized component causes the formation of a film and, therefore, the cross-linking. In the case of the solution according to the invention, the formation of a film (cross-linking) does not take place. Accordingly, no metallic ions need be used as drying agents. It has proven to be favorable when the solvent (when it has one component) or the components of the solvent are formed by carbon compounds with middle chain fatty acids. For example, MCT oils (MCT - middle chain triglyceride) are used. As a result, a solvent may be provided which is liquid at the customary conditions for printing inks/printing varnishes. In particular, a carbon chain of the solvent or of the components of the solvent comprises between 6 and 12 carbon atoms. It has proven to be favorable when the solvent components of the varnish comprise monoglycerides (monoacyl glycerols) and/or diglycerides (diacyl glycerols) and/or triglycerides (triacyl glycerols). The corresponding substances are allowed as foodstuffs. In this respect, they can form the solvent as one component or form the solvent in a mixture. Corresponding fatty acids (acryl residues) of these solvent components comprise, in particular, fatty acids (acryl residues) which have a carbon chain length of between 6 and 12. It is also possible for the solvent component alone or in combination to comprise acetylated or esterified monoglycerides and/or acetylated or esterified diglycerides and/or acetylated or esterified triglycerides. For example, corresponding emulsifiers are used as solvent components. Possible solvent components are, for example, monoglycerides and diglycerides of fatty acids esterified with edible acids, such as acetic acid ester (E 472a), lactic acid ester (E 472b), citric acid ester (E 472c), tartaric acid ester (E 472d) etc. C2 to C24 aliphatic, straight chain monocarboxylic acids (consisting of natural fats and of a synthetic origin) and their monoglycerol, diglycerol and triglycerol esters are authorized as additives without any restriction in accordance with the EC Directive 2002/72/EC relating to plastic materials. The printing of a food packaging or a contact device with a corresponding printing ink or a corresponding printing varnish conforms to the requirements as contained in Article 3 of the EC Regulation No. 1935/2004 for Food Contact Materials. It is advantageous, in particular, when the solvent component of the binding agent is essentially free from multiple bonds and, in particular, free from double bonds. As a result, oxidative breakdown products are essentially prevented. As a result, on, the other hand, the proportion of the printing ink/printing varnish from breakdown production which is capable of migration is kept small. In addition, a printing ink which is low-odor and low-swelling and a printing varnish which is low-swelling are obtained as a result. The extent of the swelling is dependent on the size of the molecules of the solvent used. In particular, the solvent (when it has one component) has or the components of the solvent have an iodine number smaller than 10 and, preferably, smaller than 1 in order to kept oxidative breakdown products low. The iodine value smaller than 0.4 is particularly preferred. It has, in addition, proven to be favorable when the molecules of the solvent or of the components of the solvent have a molecular weight of less than 1.000 daltons. This will result in an improved printability of the corresponding printing ink/printing varnish. It may be favorable when the solvent component of the binding agent is a mixture of several substances (which are each a food or authorized food additive). As a result, properties of the printing ink/the printing varnish may be set by selecting the components of the mixture accordingly. It has proven to be favorable when the weight content of the binding agent in the case of a printing ink is between 50 % and 80 %. This will result in a good printability with a good printing result. In the case of a printing varnish, the proportion of binding agent can be higher. A printing ink comprises pigments. The weight content of the pigments can be up to 35 %. It may be provided for the printing ink/the printing varnish to comprise one or more alkyd resins. Pigments may be wetted as a result of the alkyd resin. They may be distributed in the binding agent better and a high gloss is obtained as a result of printing. (In this case, the alkyd resin is considered to be a component separate from the binding agent; the corresponding weight specifications relate to the fact that the binding agent contains no alkyd resin. The alkyd resin can, however, also be allocated to the binding agent). The weight content of the alkyd resin is, in particular, below 15 %. It is, for example, below 10 %. It may be provided for the printing ink/the printing varnish to comprise auxiliary printing agents, such as, for example, an abrasion protection paste. It is favorable when the weight content of the solvent component is at the most 45 %. The solvent component is, in particular, less than 45 % in the case of inks which are not brightened. It may, for example, be below 40 %. The printing ink according to the invention/the printing varnish according to the invention favorably dries by way of ink absorption without any varnishing over being necessary. The solvent component is, in particular, liquid. A printing ink according to the invention or a printing varnish according to the invention is, advantageously, not cross-linked, i.e., there is also no formation of a film on account of cross-linking. As a result, no "cross-linking component" with a double bond or with at least one epoxidized component has to be provided. In particular, a printing ink according to the invention or a printing varnish according to the invention has no epoxidized components. Epoxidized components could, in principle, migrate into food. When no epoxidized components are' used, the production can be simplified since no cooling is necessary during the production of the binding agent. In the case of printing inks with epoxidized components, Cooling may be necessary prior to the epoxide being added on account of the reactivity of the epoxide. The printing ink according to the invention or the printing varnish according to the invention are, in addition, free from metallic ions acting as drying agents. Metallic ions are used as drying agents in the case of printing inks known from the state of the art. The printing ink according to the invention or the printing varnish according to the invention are advantageously free from mineral oils. Mineral oils are undesirable in conjunction with foodstuffs. A printing ink according to the invention or a printing varnish according to the invention may be used in an advantageous manner for a food packaging or a contact device which can come into contact and, in particular, direct contact with food. The printing ink/the printing varnish according to the invention is, in particular, an offset printing ink/printing varnish which may be used for offset printing and, in particular, for sheet-fed offset printing. In one concrete embodiment of a printing ink, a binding agent or an initial binding agent is produced first of all. For this purpose, the resin component in the solvent component is dissolved during heating. A typical temperature is, in this respect, in the order of magnitude of 200°C. The dissolving is brought about during stirring. A protective gas atmosphere with an inert gas can, in addition, also be provided. Pigments are weighed into the binding agent or initial binding agent produced. Where applicable, alkyd resin will be added. A preliminary dispersion takes place in a dissolver due to mechanical action, for example, with stirring disks. The fine dispersion takes place subsequently, for example, in a triple roller mill. Additional solvent can, where applicable, be added subsequently to the initial binding agent in order to adjust the rheology of the printing ink. This added solvent can be considered to be a component of the binding agent. In a first concrete embodiment, a printing ink blue was produced. An initial binding agent with the following composition was produced: (Table Removed) With this initial binding agent, the printing ink was then produced with the following composition: (Table Removed) The solvent content in this printing ink as produced is 40.3 % by weight. A printing ink red was produced as follows: First of all, an initial binding agent was produced with the following composition: (Table Removed) With this initial binding agent the printing ink was then produced with the following composition: (Table Removed) The solvent content in this printing ink is 37.6 % by weight. Ink absorption,test were carried out with the printing inks produced. Tn this respect, a printed sample proof was covered with a counter strip and manually guided through a roller gap. A force of 300 N acts on the strip of paper. The roller dome is turned each time through approximately 72° every 30 seconds. If the ink on the sample proof is absorbed, less ink transfers to the counter strip with increasing time. The sample proofs of these printing inks were compared with the printing ink "MGA-CORONA® 5045" of the huber group mentioned at the outset as well as with the printing ink "Oko Speed 210" of Epple Druckfarben AG. These tests have shown that the printing inks according to the invention are absorbed quickly. The printing ink "Oko Speed 210" has ink absorption properties which are classified as very quick. The printing inks according to the invention are absorbed even more quickly than "Oko Speed 210". The tested printing inks "MGA- CORONA® 5045", on the other hand, display practically no ink absorption. In the case of a printing varnish, the binding agent is, as a rule, produced in the same way as in the case of a printing ink. A printing varnish can be considered to be a printing ink without any pigment content. Additives are, where applicable, mixed into the binding agent of the printing varnish. For test purposes, an additional printing ink was produced under the designation E-29099 with the following composition: (Table Removed) Printing inks with the basic colors of yellow, magenta, cyan and black were produced individually and these four printing ink varieties were then mixed together in equal quantities for the test procedures. A test print was generated with the printing ink mixed together in this way (with the shade of brown) and a migration test was carried out on this test print. The test print was stored for ten days at a temperature of 40°C. Modified polyvenylene oxide under the trade name "TENAX" was used as a simulator for a dry food during long-term storage at room temperature. This simulation is specified in the EC Regulation "Basic Rules for Migration Testing" 97/48/EC. The transfer of tricapryl glyceride and other triglycerides with C8, C10 and C12 fatty acid patterns from the (blended) printing ink E-29099 to the food simulator could be detected by a screening analysis by means of GC-FID or GC-MC. The overall migration corresponds to a limit value of 10 mg/dm2 in accordance with EC Directive 2002/72/EC relating to plastic materials. The overall migration resulted in 60 ppm or less. Patent Claims 1. Printing ink or printing varnish for food packaging or contact devices able to come into contact with foods, comprising a binding agent with a resin component and a solvent component, characterized in that the solvent component of the binding agent is a saturated one or more component sotoent for resin, wherein the solvent or the components of the solvent are a food or a food additive. 2. Printing ink or printing varnish as defined in claim 1, characterized in that the solvent or the components of the solvent are formed by carbon compounds with middle chain fatty acids. 3. Printing ink or printing varnish as defined in claim 2, characterized in that a carbon chain of a fatty acid comprises between six and twelve carbon atoms. 4. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent comprises monoglycerides and/or diglycerides and/or triglycerides. 5. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent comprises acetylated or esterified monoglycerides and/or acetylated or esterified diglycerides and/or acetylated or esterified triglycerides. 6. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent is essentially free from multiple bonds. 7. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent or the components of the solvent have an iodine number smaller than 10. 8. Printing ink or printing varnish as defined in claim 7, characterized in that the solvent or the components of the solvent have an iodine number smaller than 1. 9. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the molecules of the solvent or of the components of the solvent have a molecular weight of less than 1.000 daltons. 10. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent is a mixture of several substances. 11. Printing ink as defined in any one of the preceding claims, characterized in that the weight content of the binding agent is between 50 % and 80 %. 12. Printing ink as defined in any one of the preceding claims, characterized by a proportion of pigments. 13. Printing ink as defined in claim 12, characterized in that the weight content of the pigments is up to 35 %. 14. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the printing ink or the printing varnish comprises one or more alkyd resins. 15. Printing ink or printing varnish as defined in claim 14, characterized in that the weight content of alkyd resin is below 15 %. 16. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the printing ink or the printing varnish comprises auxiliary printing agents. 17. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the weight content of the solvent component of the printing ink or of the printing varnish is at the most 45 %. 18. Printing ink or printing varnish as defined in any one of the preceding claims, which is dried by way of ink absorption. 19. Printing ink or printing varnish as defined in any one of,the preceding claims, characterized in that the solvent component is liquid. 20. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that no cross-linking of chemical components takes place. 21. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of epoxidized components. 22. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of metallic ions acting as drying agents. 23. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of mineral oils. 24. Use of the printing ink or the printing varnish according to any one of the preceding claims for a food packaging or a contact device able to come into contact with food. 25. Use of the printing ink or the printing varnish according to any one of the preceding claims for offset printing.

Full Text

Printing Ink or Printing Varnish for Food Packaging
or for Contact Devices which can come
into Contact with Food
The invention relates to a printing ink or a printing varnish for food packaging or for contact devices which can come into contact with food, comprising a binding agent with a resin component and a solvent component.
In the case of food packaging, a difference is made, as a rule, between primary packaging and secondary packaging. In the case of primary packaging, an outer side of the packaging is normally printed on and the food which is accommodated in the packaging touches an inner side of the packaging located opposite the oute.r side. In the case of secondary packaging, the food is accommodated in an additional wrapping which is positioned in a packaging printed, irn particular, on the outer side.
Examples for contact devices, which can come into contact with food and can, in particular, come into direct contact, are liners in food packaging or bases for foodstuffs, such as trays.
Printing ink/printing varnish components can, in principle, pass through the packaging to the food, in particular, in the case of primary packaging.
In EP 0 886 671 Bl, an offset printimg ink is described which comprises a colophony modified phenolic resin and/or a maleic resin and/or a modified hydrocarbon resin and/or a colophony resin ester. This offset printing ink has as solvent for the resin/resins one or more water-insoluble fatty acid esters of polyvalent alcohols with high steric spatial requirements and/or of ethinols, wherein the esters have steric measurements of the diameter of 2.0 to 7.0 nm and of the volume of 1.0 to 21.0 nm3. This offset printing ink is described low-migration, low-odor and low-swelling.
In the article "Spinat - und nur Spinat!" (Spinach - and only Spinach) of Klaus-Peter Nicolay in Druckmarkt 40, February 2006, pages 30 - 32, low-migration printing inks with the designation MGA of the ink manufacturer Huber are described. These dry non-oxidatively and are absorbed slowly. An inline varnishing with dispersion varnish is required.
In the Technical Information 10.1.15/11.2006/Packaging Printing/Offset Printing "MGA-CORONA® 5045" of the huber group, low-migration, organoleptically neutral sheet-fed offset inks are likewise described for the production of food packaging. These printing inks exclusively contain components with a minimum migration potential in order to prevent any undesired interaction of the printing ink with packaged foodstuffs as far as possible. These printing inks dry non-oxidatively and are absorbed relatively slowly; an inline varnishing with dispersion varnish is required. Printing stocks with a low suction capacity require the use of special dispersion varnishes. Dispensing with any inline varnishing results in a lay-up in the stack and the required abrasion resistance will not be achieved.
A printing ink on the basis of soy oil is known from US 5,178,672.
An edible ink for an ink jet printer is mentioned in US 2004/0086603.
An offset printing ink is known from DE 102 09 013 Al which comprises color pigments and a binding agent for the color pigments, wherein the binding agent comprises at least one epoxidized organic component.
The object underlying the invention is to provide a printing ink and a printing varnish for food packaging of the type specified at the outset which can be used in a simple manner.
This object is accomplished in accordance with the invention, in the printing ink'specified at the outset or the printing varnish specified at the outset, in that the solvent component of the binding agent is a saturated one or more component solvent for resin, wherein the solvent or the components of the solvent are a food or a food additive.
The binding agent consists of a resin component (with one or more resins) and a solvent component for dissolving the resin. In the case of printing inks, a binding agent for the pigments which is prepared for the production of printing inks is also designated as varnish.
In accordance with the invention, the solvent component of the binding agent is a saturated solvent for the resin with a single component or multiple components, wherein the solvent (when it has one component) or the components of the solvent (when the solvent has several components) are a food or a food additive. As a result of the use of the saturated solvent component of the printing ink or of the printing varnish, the chemical drying and, in particular, oxidative drying of the printing ink/the printing varnish is prevented during/after the printing. No breakdown products result (due to oxidative splitting of multiple bonds) which can migrate to the packaged goods which are accommodated in a packaging which is printed on accordingly. Such breakdown products can, in principle, also transfer into a gaseous phase and cause an odor impairment and swelling. In the case of the solution according to the invention, they are prevented as far as possible.
When the solvent component consists of an authorized food (of one component or several components) or of an authorized food additive of one component or several components, a migration of solvent-components into the food is not harmful. When the food or the food additive is selected so as to be
organoleptically neutral, there is no deterioration in the quality of the food which is accommodated in the food packaging printed with the corresponding printing ink or the corresponding printing varnish.
A food is defined according to Sec. 2 para. 2 of the German Laws on Food and Feed as a food within the meaning of Article 2 of the Regulation (EC) No. 178/2002. According to this Regulation, foods are all substances or products which are intended to be or are reasonably expected to be ingested by humans in a processed, partially processed or unprocessed state.
According to Sec. 2, para. 3 of the German Laws on Food and Feed, food additives are substances with or without nutritional value which are, as a rule, not eaten themselves as food nor used as a characteristic ingredient of food and which are added to food for technological reasons during production or processing, whereby they themselves or their breakdown or reaction products will or can become a component of the food directly or indirectly.
As a result of the solution according to the invention, printing inks/printing varnishes are provided which are easy to process. Varnishing over is not absolutely necessary. A harmful contamination of food does not take place since the contaminating product is itself a food or authorized food additive. A migration is, therefore, also allowed to a certain extent. As a result, the printing ink/the printing varnish can dry by way of absorption.
The printing inks/printing varnishes according to the invention are realized, for example, as offset printing inks/printing varnishes and, in particular, as sheet-fed offset printing inks/printing varnishes.
In particular, no cross-linking of the chemical components takes plac. in the case of th printing ink according to the invention and the printing varnish
according to the invention. No double bonds, which lead to filming over, are then required in the solvent and/or the resin. In the case of known printing inks which dry oxidatively, resin and/or solvent oil film over on account of double bonds whilst absorbing atmospheric oxygen, initiated by metal components, such as, for example, cobalt salts and/or manganese salts. As described in DE 102 09 013 Al, the formation of a film can also be achieved by using at least one epoxidized component instead of via oxidative drying, wherein the unlocking of the at least one epoxidized component causes the formation of a film and, therefore, the cross-linking.
In the case of the solution according to the invention, the formation of a film (cross-linking) does not take place. Accordingly, no metallic ions need be used as drying agents.
It has proven to be favorable when the solvent (when it has one component) or the components of the solvent are formed by carbon compounds with middle chain fatty acids. For example, MCT oils (MCT - middle chain triglyceride) are used. As a result, a solvent may be provided which is liquid at the customary conditions for printing inks/printing varnishes.
In particular, a carbon chain of the solvent or of the components of the solvent comprises between 6 and 12 carbon atoms.
It has proven to be favorable when the solvent components of the varnish comprise monoglycerides (monoacyl glycerols) and/or diglycerides (diacyl glycerols) and/or triglycerides (triacyl glycerols). The corresponding substances are allowed as foodstuffs. In this respect, they can form the solvent as one component or form the solvent in a mixture. Corresponding fatty acids (acryl residues) of these solvent components comprise, in
particular, fatty acids (acryl residues) which have a carbon chain length of between 6 and 12.
It is also possible for the solvent component alone or in combination to comprise acetylated or esterified monoglycerides and/or acetylated or esterified diglycerides and/or acetylated or esterified triglycerides. For example, corresponding emulsifiers are used as solvent components. Possible solvent components are, for example, monoglycerides and diglycerides of fatty acids esterified with edible acids, such as acetic acid ester (E 472a), lactic acid ester (E 472b), citric acid ester (E 472c), tartaric acid ester (E 472d) etc.
C2 to C24 aliphatic, straight chain monocarboxylic acids (consisting of natural fats and of a synthetic origin) and their monoglycerol, diglycerol and triglycerol esters are authorized as additives without any restriction in accordance with the EC Directive 2002/72/EC relating to plastic materials. The printing of a food packaging or a contact device with a corresponding printing ink or a corresponding printing varnish conforms to the requirements as contained in Article 3 of the EC Regulation No. 1935/2004 for Food Contact Materials.
It is advantageous, in particular, when the solvent component of the binding agent is essentially free from multiple bonds and, in particular, free from double bonds. As a result, oxidative breakdown products are essentially prevented. As a result, on, the other hand, the proportion of the printing ink/printing varnish from breakdown production which is capable of migration is kept small. In addition, a printing ink which is low-odor and low-swelling and a printing varnish which is low-swelling are obtained as a result. The extent of the swelling is dependent on the size of the molecules of the solvent used.
In particular, the solvent (when it has one component) has or the components of the solvent have an iodine number smaller than 10 and, preferably, smaller than 1 in order to kept oxidative breakdown products low. The iodine value smaller than 0.4 is particularly preferred.
It has, in addition, proven to be favorable when the molecules of the solvent or of the components of the solvent have a molecular weight of less than 1.000 daltons. This will result in an improved printability of the corresponding printing ink/printing varnish.
It may be favorable when the solvent component of the binding agent is a mixture of several substances (which are each a food or authorized food additive). As a result, properties of the printing ink/the printing varnish may be set by selecting the components of the mixture accordingly.
It has proven to be favorable when the weight content of the binding agent in the case of a printing ink is between 50 % and 80 %. This will result in a good printability with a good printing result. In the case of a printing varnish, the proportion of binding agent can be higher.
A printing ink comprises pigments. The weight content of the pigments can be up to 35 %.
It may be provided for the printing ink/the printing varnish to comprise one or more alkyd resins. Pigments may be wetted as a result of the alkyd resin. They may be distributed in the binding agent better and a high gloss is obtained as a result of printing. (In this case, the alkyd resin is considered to be a component separate from the binding agent; the corresponding weight
specifications relate to the fact that the binding agent contains no alkyd resin. The alkyd resin can, however, also be allocated to the binding agent).
The weight content of the alkyd resin is, in particular, below 15 %. It is, for example, below 10 %.
It may be provided for the printing ink/the printing varnish to comprise auxiliary printing agents, such as, for example, an abrasion protection paste.
It is favorable when the weight content of the solvent component is at the most 45 %. The solvent component is, in particular, less than 45 % in the case of inks which are not brightened. It may, for example, be below 40 %.
The printing ink according to the invention/the printing varnish according to the invention favorably dries by way of ink absorption without any varnishing over being necessary.
The solvent component is, in particular, liquid.
A printing ink according to the invention or a printing varnish according to the invention is, advantageously, not cross-linked, i.e., there is also no formation of a film on account of cross-linking. As a result, no "cross-linking component" with a double bond or with at least one epoxidized component has to be provided.
In particular, a printing ink according to the invention or a printing varnish according to the invention has no epoxidized components. Epoxidized components could, in principle, migrate into food. When no epoxidized components are' used, the production can be simplified since no cooling is
necessary during the production of the binding agent. In the case of printing inks with epoxidized components, Cooling may be necessary prior to the epoxide being added on account of the reactivity of the epoxide.
The printing ink according to the invention or the printing varnish according to the invention are, in addition, free from metallic ions acting as drying agents. Metallic ions are used as drying agents in the case of printing inks known from the state of the art.
The printing ink according to the invention or the printing varnish according to the invention are advantageously free from mineral oils. Mineral oils are undesirable in conjunction with foodstuffs.
A printing ink according to the invention or a printing varnish according to the invention may be used in an advantageous manner for a food packaging or a contact device which can come into contact and, in particular, direct contact with food.
The printing ink/the printing varnish according to the invention is, in particular, an offset printing ink/printing varnish which may be used for offset printing and, in particular, for sheet-fed offset printing.
In one concrete embodiment of a printing ink, a binding agent or an initial binding agent is produced first of all. For this purpose, the resin component in the solvent component is dissolved during heating. A typical temperature is, in this respect, in the order of magnitude of 200°C. The dissolving is brought about during stirring. A protective gas atmosphere with an inert gas can, in addition, also be provided.
Pigments are weighed into the binding agent or initial binding agent produced. Where applicable, alkyd resin will be added. A preliminary dispersion takes place in a dissolver due to mechanical action, for example, with stirring disks. The fine dispersion takes place subsequently, for example, in a triple roller mill.
Additional solvent can, where applicable, be added subsequently to the initial binding agent in order to adjust the rheology of the printing ink. This added solvent can be considered to be a component of the binding agent.
In a first concrete embodiment, a printing ink blue was produced.
An initial binding agent with the following composition was produced:
(Table Removed)
With this initial binding agent, the printing ink was then produced with the following composition:
(Table Removed)
The solvent content in this printing ink as produced is 40.3 % by weight.
A printing ink red was produced as follows:
First of all, an initial binding agent was produced with the following composition:
(Table Removed)
With this initial binding agent the printing ink was then produced with the following composition:
(Table Removed)
The solvent content in this printing ink is 37.6 % by weight.
Ink absorption,test were carried out with the printing inks produced. Tn this respect, a printed sample proof was covered with a counter strip and manually
guided through a roller gap. A force of 300 N acts on the strip of paper. The roller dome is turned each time through approximately 72° every 30 seconds. If the ink on the sample proof is absorbed, less ink transfers to the counter strip with increasing time. The sample proofs of these printing inks were compared with the printing ink "MGA-CORONA® 5045" of the huber group mentioned at the outset as well as with the printing ink "Oko Speed 210" of Epple Druckfarben AG. These tests have shown that the printing inks according to the invention are absorbed quickly. The printing ink "Oko Speed 210" has ink absorption properties which are classified as very quick. The printing inks according to the invention are absorbed even more quickly than "Oko Speed 210". The tested printing inks "MGA- CORONA® 5045", on the other hand, display practically no ink absorption.
In the case of a printing varnish, the binding agent is, as a rule, produced in the same way as in the case of a printing ink. A printing varnish can be considered to be a printing ink without any pigment content. Additives are, where applicable, mixed into the binding agent of the printing varnish.
For test purposes, an additional printing ink was produced under the designation E-29099 with the following composition:
(Table Removed)
Printing inks with the basic colors of yellow, magenta, cyan and black were produced individually and these four printing ink varieties were then mixed together in equal quantities for the test procedures.
A test print was generated with the printing ink mixed together in this way (with the shade of brown) and a migration test was carried out on this test print. The test print was stored for ten days at a temperature of 40°C. Modified polyvenylene oxide under the trade name "TENAX" was used as a simulator for a dry food during long-term storage at room temperature. This simulation is specified in the EC Regulation "Basic Rules for Migration Testing" 97/48/EC.
The transfer of tricapryl glyceride and other triglycerides with C8, C10 and C12 fatty acid patterns from the (blended) printing ink E-29099 to the food
simulator could be detected by a screening analysis by means of GC-FID or GC-MC.
The overall migration corresponds to a limit value of 10 mg/dm2 in accordance with EC Directive 2002/72/EC relating to plastic materials.
The overall migration resulted in 60 ppm or less.

Patent Claims
1. Printing ink or printing varnish for food packaging or contact devices
able to come into contact with foods, comprising a binding agent with
a resin component and a solvent component,
characterized in that the solvent component of the binding agent is a saturated one or more component sotoent for resin, wherein the solvent or the components of the solvent are a food or a food additive.
2. Printing ink or printing varnish as defined in claim 1, characterized in that the solvent or the components of the solvent are formed by carbon compounds with middle chain fatty acids.
3. Printing ink or printing varnish as defined in claim 2, characterized in that a carbon chain of a fatty acid comprises between six and twelve carbon atoms.
4. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent comprises monoglycerides and/or diglycerides and/or triglycerides.
5. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent comprises acetylated or esterified monoglycerides and/or acetylated or esterified diglycerides and/or acetylated or esterified triglycerides.
6. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent is essentially free from multiple bonds.
7. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent or the components of the solvent have an iodine number smaller than 10.
8. Printing ink or printing varnish as defined in claim 7, characterized in that the solvent or the components of the solvent have an iodine number smaller than 1.
9. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the molecules of the solvent or of the components of the solvent have a molecular weight of less than 1.000 daltons.
10. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the solvent component of the binding agent is a mixture of several substances.
11. Printing ink as defined in any one of the preceding claims, characterized in that the weight content of the binding agent is between 50 % and 80 %.
12. Printing ink as defined in any one of the preceding claims,
characterized by a proportion of pigments.
13. Printing ink as defined in claim 12, characterized in that the weight content of the pigments is up to 35 %.
14. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the printing ink or the printing varnish comprises one or more alkyd resins.
15. Printing ink or printing varnish as defined in claim 14, characterized in that the weight content of alkyd resin is below 15 %.
16. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the printing ink or the printing varnish comprises auxiliary printing agents.
17. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that the weight content of the solvent component of the printing ink or of the printing varnish is at the most 45 %.
18. Printing ink or printing varnish as defined in any one of the preceding claims, which is dried by way of ink absorption.
19. Printing ink or printing varnish as defined in any one of,the preceding claims, characterized in that the solvent component is liquid.
20. Printing ink or printing varnish as defined in any one of the preceding claims, characterized in that no cross-linking of chemical components takes place.
21. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of epoxidized components.
22. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of metallic ions acting as drying agents.
23. Printing ink or printing varnish as defined in any one of the preceding claims, characterized by the absence of mineral oils.
24. Use of the printing ink or the printing varnish according to any one of the preceding claims for a food packaging or a contact device able to come into contact with food.
25. Use of the printing ink or the printing varnish according to any one of the preceding claims for offset printing.

Documents:

http://ipindiaonline.gov.in/patentsearch/GrantedSearch/viewdoc.aspx?id=TYLSd7/NPEOvZRCRItu+nQ==&loc=+mN2fYxnTC4l0fUd8W4CAA==

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Patent Number

270759

Indian Patent Application Number

5277/DELNP/2009

PG Journal Number

04/2016

Publication Date

22-Jan-2016

Grant Date

18-Jan-2016

Date of Filing

17-Aug-2009

Name of Patentee

EPPLE DRUCKFARBEN AG

Applicant Address

GUTENBERGSTRASSE 5, 86356 NEUSAESS-AUGSBURG, GERMANY.

Inventors:

#	Inventor's Name	Inventor's Address
1	EPPLE, CARL	HALLSTRASSE 12 86150 AUGSBURG GERMANY.
2	EISELE-KOHLER, ARTUR	RITTER-VON-STEINER-STRASSE 5 86161 AUGSBURG, GERMANY.

PCT International Classification Number

C09D 11/00

PCT International Application Number

PCT/EP2008/052630

PCT International Filing date

2008-03-04

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	10 2007 012264.2	2007-03-06	Germany