MXPA97009166A - Anti-abrasion ink additives and printing inks containing such additives - Google Patents

Abstract

An improved anti-abrasion/slip ink additive is disclosed comprising a mixture of sintered polytetrafluoroethylene and pharmaceutical grade petrolatum. As an alternative, additional material, such as phenolic resins and oils can be added to the mixture. The additives permit the less costly manufacture of printing inks, most particularly heat set inks and results in print which has improved rub, slip and anti-mar characteristics.

Description

ANTI-ABRASIVE INK ADDITIVES AND PRINTING INKS CONTAINING SUCH ADDITIVES BACKGROUND OF THE INVENTION This invention relates to anti-abrasive additives for printing inks. Such additives are chemicals mixed or dispersed in ink formulations in order to impart to such inks properties of tensile strength and anti-abrasive after. that printing with the ink formulation has occurred. These products are often referred to as additives for slip ink, anti-spoiling, or anti-abrasive. Printing on paper using ink containing these additives, for example, will then be protected against abrasion while maintaining sliding properties, defined below, when the ink, and paper or other material are subjected to a variety of staining forces , blurring and -deterioration. Such forces occur during the use, transportation or handling of the paper. The present invention is more useful for thermoset, continuous foil and UV coatable printing inks. Description of the prior art It has been known that the printing ink must be provided with strength properties, so that after printing on paper or other substrates, the printing ink is not erased when the surface of the substrate is subjected to the forces normal abrasives found in the use and handling. Thermoset inks, for example, have been made with special additives, designed to provide these properties. The printing ink, as modified by the manufacturer, will possess improved resistance to spoilage after it is used for printing. The spoiling of the print denigrates the readability that the printed message is intended to convey to the reader. The treated ink, after the addition of these special additives, will often also have improved slip properties. Sliding properties allow others. Printed pages slide easily over the ink on the printed page without causing the ink to be erased. Anti-abrasive additives are added in the printing ink formulations during manufacture when mixed, or ground, in the ink formulation with the pigment used to make the ink, are added as a part of the final ink mixture, or induced in the ink. other times. Such additives, for example, are often dispersed in the precursor ink solvents or resins. The antiabrasive ink additives in commercial use today are usually in the form of a wax, solid or powder type. Hard waxes have proved difficult to mix or disperse satisfactorily in ink systems as additives. It has often been necessary to melt the wax additive by electric or other heating, as part of the final printing ink manufacture. The anti-abrasive or anti-wear qualities imparted by common commercial waxes are highly influenced by the melting temperature of a particular wax. Many waxes added to the inks, often result in only a small reduction of effacement, not its complete elimination, the heat and movement imparted by the friction wear constant in practice sometimes results in the particles of the printed film of ink often continued to scatter in unprinted areas. In view of these and other difficulties, the anti-abrasive ink additives have not achieved their full market potential. The introduction of hard anti-abrasive waxes in the inks in order to solve the wear problem, however, has introduced other problems. Often, the more wax additive that is added to improve the. Resistance to wear, is more significant the decrease in desirable brightness of the printed ink compared to the brightness when printed, at a lower level, which is particularly unsatisfactory for the quality of magazines or printed matter. It is very important for a publicist to minimize this reduction in brightness of the printed ink due to. the abrasion forces. Consequently, in most applications a compromise must be made between the desired level of anti-abrasive properties and the amount of gloss reduction.

Because many anti-abrasive waxes are in solid or powder form, they are often difficult to disperse in formulations, which are essentially liquid systems. Ink manufacturers have long searched for more uniform and easy-to-handle products. for use as anti-abrasive additives, for the ease of manufacturing single ink. An additive that requires heating, such as anti-abrasive additive products, also represents manufacturing costs and additional problems, which ink manufacturers prefer to avoid. In addition, there is an increased cost factor associated with an ink containing relatively expensive anti-spoilage additives. In the case of newspapers and some news magazines, cost is an important factor and, therefore, many new inks do not ordinarily use anti-abrasive additives, and cheap magazine inks do not ordinarily use anti-abrasive additives, and expensive magazine inks use only limited varieties and in small quantities. Polyethylene waxes have been used as anti-abrasive additives in the ink industry. These waxes are added, usually incorporated by the ink manufacturer as dispersions of the wax in resins, generally of the same type of characteristics of the ink formulations in which they are to be incorporated. Waxes prepared with certain types of polytetrafluoroethylene are known, especially focused for thermoset inks, where the temperature of the drying apparatus does not cause them to be spoken or founded in an important way. Particular classes of polytetrafluoroethylene-based waxes have also been added directly to the in-process inks using shear forces. The incorporation of many commercial waxes presents similar problems of conventional handling as they are found with the dispersion of other types of solid or semi-solid materials. When added to the ink systems, these types of waxes can agglomerate into lumps. When they disperse directly, the "non-uniform wetting" of the product has been reported resulting in pieces or globules whose core is still wax. Such agglomeration can be reduced in many cases by adding the wax to the system slowly, with agitation. However, such slow dissolution often influences the efficiency of specific ink manufacturing operations. Some waxes have proven difficult to incorporate into ink manufacturing processes because they often require formulations comprising other chemicals and ingredients, prolonged periods of agitation and aging are necessary before the correct viscosity and dispersion can be achieved. Ink manufacturers have continuously searched for simple, fast and effective ways to mix anti-abrasive additives in ink systems. Because this desire and research continues, some commercial products are used by manufacturers as pourable liquid "concentrates". These additives, in the form. Liquid for inks and other compositions, usually involves taking the wax sold by an ani-abrasive wax manufacturer and preparing, by the ink manufacturer, in its ink manufacturing operation a pre-mixed liquid mixture of the wax anti-abrasive and the used ink vehicle to be incorporated into the ink formulation. Commercially available anti-wear wax additives include Protech 120, sold by Carrol Scientific, Inc., which is described as an 83% active compound containing a form of DuPont virgin Teflon® and a blend of synthetic wax with a petroleum distillate vehicle. Another company, Lawter International, sells an additive product for hard-wear anti-wear wax, designated Lawter SA-1021, which comprises a phenolic resin, some type of polytetrafluoroethylene, and petroleum oil. Commercial wax additives containing polytetrafluoroethylene have also been sold in the past which may also have contained small amounts of some type of polyalphaolefins. It is also believed that an additive product for commercial ink from Sun's Chenical Compañy's past, which is no longer available for sale, used a combination of non-sintered PTFE with large and varied particle size in combination with other ingredients that include low-grade petrolatum. In addition, it is also believed that such products were withdrawn from the market because they did not satisfy the market. A number of prior art patents disclose the use of ink additives of the general type described in U.S. Patent No. 5,024,700 discloses the use of triethanolamine as an ink additive, which among other properties, is disclosed to impart improved strength to the wear for oil-based and resin-based ink compositions. The product is claimed to be particularly useful for applications in the printing of newspapers in this regard: U.S. Patent No. 5,035,836 shows a strong ink using a polymer-based binder and a solid electrically conductive lubricant. use of polytetrafluoroethylene in non-ink applications, see for example US Pat. No. 5,159,019 which teaches the use of polytetrafluoroethylene in a resin mixture to impart resistance to injection molded plastic materials. shows the use of polytetrafluoroethylene to improve the abrasion resistance of elastomers of a type that is in dynamic contact with metals.

U.S. Patent No. 5,158,606 describes a printing ink composition with a high degree of erasure resistance comprising: a) a dispersion of a pigment in a carrier it contains. an oil and b) polymer latex emulsified in said dispersion. The subsequent patent discloses that when the cost is not, it is an extreme concern, a wax of polytetrafluoroethylene with petrolatum can be added to the oil ink / latex polymer composition. U.S. Patent No. 3,843,570 describes a porous material comprising polytetrafluoroethylene obtained by polymerizing a monomer capable of forming a resin and discloses that the material is suitable with inks. OBJECTIVES OF THE INVENTION It is an object of this invention to provide an anti-abrasive ink additive with improved resistance to spoilage and anti-wear properties compared to existing additives. Accordingly, it is a further object of the present invention to substantially solve or alleviate the problems created by most anti-abrasive additives for hard wax type ink. It is therefore a more specific objective of the present invention to provide an additive for slip, anti-spoilage and anti-abrasive ink. (defined as an anti-abrasive additive) which is useful for increasing the performance properties of inks in an efficient and improved manner. The additive maintains good gloss degradation properties in the ink formulation in which it is used. Along with the obvious advantages and cost savings that can be realized in transporting such an anti-abrasive additive, such a product has the additional advantage of being largely free of resins and solvents. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT In one embodiment, the anti-abrasive ink composition of this invention is a mixture comprising: a) from 40 to 70 parts by weight of polytetrafluoroethylene and b) from 30 to 60 parts by weight of one or more pharmaceutical grade petrolatums. The combination of pblitetrafluoroethylene with pharmaceutical grade petrolatum in the above-described definition leads to a unique, cost-effective additive having synergistic properties that impart good slip, abrasion resistance, low cloudiness and resistance to spoilage when dispersed in the ink. The parts by weight are in relation to the two ingredients together. The mixture may contain additional ingredients including resins and oils. It is more preferred that an anti-abrasive composition containing additional ingredients have, by weight, the complete composition of 50-60, or more of the two specific materials described above. Polytetrafluoroethylene (PTFE) is a tetrafluoroethylene polymer. The substance is essentially a very long molecular chain of repeating units [-CF2-CF2-] n. When formed it has a milky white color, and can be molded into powder by metallurgical techniques, which involve mixing with a diluent that is subsequently removed. PTFE is usually produced as a white thermoplastic powder that has a melting point of about 327 ° C (621 ° F). This material as it is manufactured, is characterized by its quality of being chemically inert, high service temperature, excellent electrical properties - - a low coefficient of friction. PTFE was originally 'invented by scientists employed by E.l. DuPont de Nemours. And Company, Inc. (DuPont) and is still sold by DuPont- under the Teflon® brand. DuPont currently provides the product in various grades of purity and reprocessing and in various particle sizes and grindings. Polytetrafluoroethylene is often industrially produced by the polymerization of tetrafluoroethylene monomers dispersed in an aqueous phase either in the form of an emulsion or suspension in the presence of an emulsifying or dispersing agent, using free radical generators as a catalyst. that this process can be carried out at the beginning of the polymerisation with ionizing radiation instead of using free radical generators in the presence of the agent either emulsifying or dispersing.The PTFE retains without useful properties up to 350 ° -450 ° C and It is essentially non-flammable at these temperatures PTFE is highly resistant to oxidation and the action of chemicals, including strong acids, alkaline agents and oxidants, and is resistant to nuclear radiation and UV, ozone and weather. The PTFE has been and is. used in packaging, seals, flexible hoses, coatings, rocket and spacecraft, chemical process equipment, coatings for coaxial coils, separators, insulators, coatings for wire and tapes in the fields' .. electric and electronic, bearings, seals, rings: piston, felt, packaging and supports. The tetrahalo-substituted ethylenes, more specifically PTFE, are used as starting materials in the preparation of homo-polymeric substances and copolymers. PTFE finds a wide variety of uses in commercial applications in addition to those discussed above. For example, the polymer is best known as a thin coating for kitchen utensils such as satins and frying pans, thereby eliminating the problem of food and burnt remains of food adhering to the surface of the kitchen utensil. . The various uses of polytetrafluoroethylene are estimated from the physical properties of the polymer, such that it is not flammable, as well as being highly resistant to oxidation and the action of chemicals including strong acids, alkalis and oxidants. Preferred PTFE forms useful for the present invention include high molecular weight types, (as high as 40 million), which have been sintered and pre-milled and are in powder form. As a preferred component, PTFE has also been subjected to a certain degree of irradiation. The PTFE particularly found useful for this invention can be obtained as a special product from a variety of companies, including .. DuPont, Royce Company, Imperial Chemicals International, Ltd. (ICI), Hoescht (Germany), Cray Valley, Ltd., - North America Fluorpolymer, Shamroc / MP Company, Ausimont, Daikin, and PTK International Limited together with numerous others ... The PTFE used for this invention must be sintered during or after its manufacture . This sintering involves the agglomeration of PTFE at temperatures slightly below or slightly above its melting point. It is believed that such sintering that "increases the density and strength of PTFE as an ink additive." While heat and pressure are essential for sintering, the decrease in PTFE surface area is probably the most important factor to achieve The desired results of this invention Some preferred types of polytetrafluoroethylene powder for this invention are preformed under pressure in a desired form, and then sintered at atmospheric pressure in an oven at a temperature in the range of 700 ° F to 750 ° F. Other types of useful PTFE powders can be preformed under pressure and sintered under pressure, typically at a temperature in the range of about 600 ° F to 750 ° F. Accordingly, U.S. Patent No. 3,766,031, as of the date of patent, none of these sintered materials could easily be processed into fine particles, for example, a polytetrafluoroethylene This is described in the patent which can only be reduced by high-impact spraying at a size range of 100 to 2 f mesh (149 to 74 microns), and this can be carried out only with the associated use of refrigerants, such as dioxide. liquid carbon or liquid nitrogen. Many types of PTFE powder useful for this invention are often referred to as "granular" because they are of a small particle size and have a granular texture in which the particles are not smooth and uniform. In the present invention, sintered PTFE in powder form is preferred. The irradiation of PTFE powder is usually preferred to facilitate microminiaturization of PTFE in a powder form useful for the use of this invention; however, the irradiation of unsintered PTFE can also produce PTFE of particle size discussed above - see U.S. Patent No. 4,036,718, which shows non-sintered PTFE of small size in microns. It is also believed that proprietary, non-irradiated processes are now employed by suppliers that produce commercially available small particle size PTFE useful for this invention. The term "irradiation" when used with PTFE is defined for purposes of this invention as exposure to wavelengths shorter than those of visible light. This includes treatment with alpha rays, beta rays, gamma rays, X-rays, electron beams, ultraviolet (UV) rays, neutron beams, proton beams, and the like. Particularly preferred for this invention are the virgin irradiated sintered grades and similar reprimed grades, the specific types of useful irradiated sintered PTFE include virgin granular products.The microminiatization of the sintered PTFE to a particle size of about 2 to 20 microns is preferred. For this invention, sintered PTFE having a particle size of about 2 to 10 microns is more preferred, being 2 to 5 microns (less than 1% of the particles being greater than 10 microns) being the most preferred. one millionth (10 ~ 6) of a meter or 10,000 Angstroms The icrominiaturization can be carried out by a variety of techniques, including grinding and grinding.The average and average particle size can be determined by well-known mesh and sieve tests in the technique, as well as, by the "use of other more accurate tests when working with PTFE finely divided. See, for example, the tests described in US Pat. No. 3, 983,200 (ratio of air sediment using Stokes law) and US Patent No. 4,036,718 (optical test). Sintered PTFE - out of specification and recycled or reprocessed, as well as virgin PTFE can be used to make products useful in this invention. Mixtures of various types of PTFE .. 'are also useful. A more preferred PTFE for this invention could be an irradiated and sintered granular product which has been microminiaturized to an average particle size of about 2.5 microns. PTFE of this type is commercially available from some of the. above mentioned suppliers. The second critical element for producing the additives of this invention is pharmaceutical grade petrolatum. This is also sometimes referred to as laboratory-grade petrolatum. Petrolatum is a mass of ointment-like consistency obtained from crude oil and is chemically related to white mineral oil. In contrast to white mineral oil, which consists mainly of hydrocarbons that are liquid at ordinary temperatures, petrolatum is often a mixture of solid and liquid hydrocarbons. The majority of manufactured petrolatums are largely recessed waxes and are low grade with a high oil content. Petrolatum is generally obtained from crude oils based on paraffin and mixed base. The manufacturing method varies with the type of petrolatum used, the desired petrolatum grade and the general program of the individual refinery. The "refining" procedure, however, is almost always in accordance with the following: Crude oil is first subjected to a fractional distillation to obtain a distillation residue of a predetermined viscosity, taking care not to fractionate the residue by excess hot; otherwise, the crude petrolatum obtained in the following operation may be unsuitable for the production of finished petrolatum from the structural point of view. The residue is released from the asphalt by treatment with a solvent, such as propane, prior to the operation of desiccation. The distilled and de-asphalted residue is then dessicated to give crude petrolatum and lubricating oil. Decerification is usually carried out by dissolving the residue in special solvent, such as a combination of toluene and methyl ethyl ketone, freezing to obtain crystallization and then filtered, usually by means of a rotary vacuum filter. The product obtained by this process is then carefully distilled to remove all traces of the desiccant solvent and as such. It is known as crude petrolatum. The melting point, oil content and other properties of crude petrolatum can be controlled by the temperature at which the filtration takes place, the solvent ratio used, and the geographical origin of crude oil. Because the crude petrolatum is only one, and possibly the least important of the two products obtained by the de-oiling operation, the refining stage is very sensitive to obtain the pharmaceutical grade petrolatum. The refinery must not only produce a crude petrolatum which finally gives the North American Pharmacy (USP) useful for this invention, but must at the same time be sure that the lubricating oil obtained will meet its own specifications. manufacturing. Several crude oils require specific conditions of racified distillation and decerification; , and this can further complicate the refinery process. The crude petrolatum is then purified to meet the requirements of the North American patent and the PFA by high pressure / high temperature hydrogenation. The specifications for pharmaceutical grade petrolatum require the following: 1. Color - yellowish to slightly amber 2. Specific gravity - 0.815 to - 0.880 to 60 ° C 3. Melting point - 38 ° to 60 ° C 4. Consistency - 100 -275 5. Residue of ignition - 0.10 max. 6. Organic acids - none 7. Fixed oils, greases and rosins - none To help select the appropriate grade of petrolatum for a given purpose and establish specifications, the American Society for Testing Materials (ASTM acronyms in English) has developed , many test methods. These methods are widely accepted as standards throughout the industry. The tests include ,. A. Melting point (two types) - ASTM D938 is used to determine the freezing point of petrolatum. The freezing point is the temperature at which the material solidifies when it freezes. The melting point of USP (ASTM D-127) is used to determine the melting point of petrolatum precipitation. The melting point is determined to be the temperature at which the first drop of petrolatum falls from a thermometer when heated under specific conditions. _. B. Consistency (Penetration) - ASTM D 937 determines the consistency (hardness or softness) of petrolatum; the lower the numerical value, the greater the hardness of the petrolatum.

C. Viscosity - ASTM D'445 and ASTM D 2161 are methods for the measurement of kinematic viscosity in centistokes and the conversion to Saybolt viscosity in Universal seconds.

Saybolt (SUS of the abbreviations in English), respectively. Both methods measure the mobility of molten petrolatum, usually @ 210 ° F or 100 ° C. - ' D. Discharge Point - ASTM D 92 is the procedure for determining the points of discharge and ignition of petrolatum products through the Cleveland Open Cup tester. Pharmaceutical grade petrolatums can find application in numerous applications. As such, its degree of purity is regulated by FDA requirements as specified in 21 CFR 172.880. The test procedure is detailed in the previous Federal Code of Rules. Particularly preferred petrolatums for this invention are Protopet from Witco Chemical Company, Perfecta grades and Fonoline. Particularly useful in the formulation of the present invention are the oils made by several companies, including Witco's Protopet line as the most exemplary material. The Protopet line from Witco particularly combines a less oily consistency, is odorless and is in accordance with the pharmacopoeia requirements of Europe and the United States. Witco Protopet ÍS has the following specifications and typical properties: PROTOPET SPECIFICATIONS ÍS PROPERTIES TEST METHOD FOR INTERVAL DETERMINATE Specific gravity @ 60 ° C / 25 ° C LATM 128 0.815 / 0.880 Melting point, ° C ASTM D -127 '54.4 / 60.00 Consistency ASTM D937 - .. 180/210 Residue of ignition USP 23 Pasa Alkalinity USP 23 '. Passes USP 23"'Acid, Passes Fixed oils, fats and rosins USP 23 Pasa Color USP 23 Passes Color Lovibond, Cell 2", and IP 17 1.5 / 2.0 Reason of smell, average panel LATM 093 - 1.0 Max.

TYPICAL PROPERTIES FOR WHITE PROTOPET ÍS PROPERTIES TEST METHOD TYPICAL VALUE Freezing point, ° F ASTM D938 115/128 Viscosity @ 100 ° C, SUS ASTM D445 60/75 Discharge point, COC, ° F ASTM D92 420 min Protopet IS is a USP petrolatum that meets the requirements of USP 23 and FDA with respect to 21 CFR 172.880. A preferred embodiment of the present invention contains approximately 50% of each of the two chemicals mentioned, without additional additives other than PTFE and laboratory-grade petrolatum. Additional chemicals that may be optionally added to form another inventive composition include narrow-cut petroleum oils, and soluble hydrocarbons or phenolic resins. An inventive composition containing chemicals in addition to the two basic ingredients mentioned above has also proved useful. Such a composition contains from about 30-60% of the defined PTFE, from about 25-35% pharmaceutical grade petrolatum, from about 5-15% petroleum oil and gives about 5-15% of a hydrocarbon or phenolic resin. The percentages are parts by weight taking into account the four ingredients in the final composition. A preferred type of petroleum oil is Magie oils, "oil-for-ink" solvents which are narrow-cut oils made and sold by Magie Brothers Inc., a Pennzoil Division.The commercial products designated Magie Oil 47. and 470 are Particularly preferred are oils designated Amprint 231 from Total Petroleum and a similar line of petroleum products sold by Exxon Corp. Hydrocarbon resins supplied by Neville Chemical Company, Pittsburgh, Pennsylvania, designated Nevchem 110 and Nevchem 140, are representative of a wide variety of hydrocarbon resins useful in this invention. Also useful are resins sold by Arizana Chemical, Panama City, Florida under the Betabrene and Betalite brands including Betabrene 255, and Resinall Corporation, North Carolina, particularly products of the Resinall brand designated resinall 737, 747, 771 and 74S.- Phenolic resins are sold by Arizona Chemical under the trademark Beckatite including Beckatite 112, 115, 6004 and 6006. The composition of this invention can be prepared with a wide variety of industrial mixing apparatuses, including mills and blade mixers. Other types of similarly useful apparatus are well known in the art.

The initial chemicals can be added together in any order, with the addition of petrolatum added first and then PTFE added as the preferred method. The mixture is then incorporated, sheared or stirred for a period of time necessary to achieve satisfactory dispersion, which may be in some cases no longer than a few minutes to several hours. In many embodiments, the resulting blend product will have the consistency of uniform light cream and is pumpable; often the mixture will have a creamy white color too, and will not feel gritty to the touch. While "pourable" and "pumpable" are terms that resist precise definitions, a definition of "work" is given in this application as follows: (a) "pourable" generally means that the product exhibits viscosity of 15,000 cps or less at 25 ° C, as measured with a Brookfield RVT Micrometer @ 50 rpm using a # 4 spindle examples of products that are pourable include honey, molasses, and liquid washer (b) "Pumpable" products exhibit 15,000 cps or lower viscosity at the pumping shear rate, pumpable products could include pourable products, pumpable substances can be non-pourable (up to 75,000 cps) under static condition, but fall at 15,000 cps or less under shear due to their slimming response Examples of pumpable products include: building pastes and grouts, mayonnaise-like substances and soft shoe shine, while not descending to the theory to, it is believed that the additive formulation of the two ink defined above components creates a synergism when the specific petrolatum acts both as an initiate and a carrier for the sintered PTFE. When used in the designated ratios the petrolatum "sets" and decondenses the PTFE, thereby creating a tough barrier when using "ink formulations such as for UV-curable inks for fed sheet." Inventive compositions can be prepared using machinery currently used to prepare the existing formulations.While the relative amounts may vary, in general, the anti-abrasive composition will preferably cover from 0.1 to 10% by weight of the ink to be treated. the most preferred levels of use- with 0.25% to 7% of the blend composition for the ink system, the percentage being based on the ink system that will be affected.All types of inks can benefit from the ink additive. the inventiveness, being the termoxijas inks of high quality the most benefited.The use of the composition 'd the invention is a bit similar for the use of aditi currently commercial, and in general should not require arrangements or special devices when such compositions are incorporated into the ink systems. The anti-abrasive composition can be easily mixed into the ink system using conventional mixing equipment, such as medium and high speed dispersion apparatuses, and similar mixing apparatuses. Substantially less time and shear will be required to obtain the effective dispersion of the inventive additives compared to many commercial products today. The additives are particularly useful in inks of. quality for magazine covers and color ad inserts commonly contained in magazines such as Natio al Geographics and Cosmopolitan. The product of this invention, particularly those that are pumpable, can be easily dispersed in most liquids. The product can be added directly into a masterbatch 4e ink using an appropriate mixer. The printing ink compositions using the present invention can be prepared by conventional techniques, for example, by preparing a dispersion of the pigment in the ink vehicle and adding the additive. A preferred process for preparing the ink compositions of the present invention is as follows: a) dispersing the pigment in a vehicle, forming an ink formulation, and then b) dispersing the additive of the inventive in the ink formulation, and then mixing the ink formulation for a short period of time. An offset printing ink composition can be made as follows: a) Prepare a dispersion of 5-30 percent by weight of ink pigment in 70-90 percent by weight of an ink vehicle; and b) adding a load of 2-5 percent by weight, based on the weight of the composition-of ink, of the polytetrafluoroethylene / petrolatum additive of the invention, incorporated in the previous dispersion, comprising said additive of 40-60 percent in weight. weight of polytetrafluoroethylene being the rest petrolatum. The anti-abrasive compositions of the inventive provide substantially improved anti-abrasive properties, including improved smudging and slip, to a wide variety of printing inks as compared to current additives. Because the additives are pumpable, elaborate heating and mixing apparatuses are often not required, and the additives are a more economical result to use. The use of polyalphaolefin also decreases the cost of the additive, and allows the decreased use of polyalphaolefin in some inks, whose properties can result in a lower cost product. The . Following examples are illustrations designed to assist those skilled in the art in ink formulation and additive technique in practicing the present invention, but are not intended to limit the broad scope of the invention. Various modifications and changes can be made without departing from the essence and spirit of the invention. The various chemicals used in the examples are commercial materials, except for the compositions of the inventive. . EXAMPLES Example 1 A number of ink formulations were prepared using the compositions of the present invention. Composition A was a mixture of 50% granular PTFE of an average particle size of about 5 microns (which had been irradiated) and 50% of laboratory petrolatum. The test results of a commercial wax anti-abrasive additive containing PTFE in dispersion available from Lawter International, designated Lawter Standard by Sun Printing Ink Company, were used for comparison. The tests were also run without any additives. The ink formulation used, prior to the addition of the additive, was a zero grinding thermoset ink obtained from Sun Chemical. The additives were dispersed in the basic ink formulation using a Cowles mill at 2000 RPM for 15 minutes. The ink was printed on cover material, dried using a Sinvater dryer and "rubbed or weathered" using a Sutherland wear test. The Sutherland test involved 50 strokes with a weight of 1.82 kg covered with a paper substrate using a mechanical device known as the Sutherland wear tester. The gloss was measured using a gloss meter. The additive charge used was 7% by weight. The results are reported in Table I. Densities were taken using a McBeth densimeter before the ink films were evaluated. The brightness degradation determinations were removed as follows: TABLE '' I ' Discussion of results: The above results show significantly less before and after effect on gloss using the additive of the inventive compared to a commercial standard. These results show that the brightness of the standard grades proves to be more under pressure than the sample made according to the invention. Example 2 The following tests were run to measure the amount of "smudging" or deterioration of the ink formulation, with various additives found. A test of resistance to damage / wear was carried out. The test of damage / wear is one of the most critical measurements of performance in the test of printing inks. The results simulate the printed package, regardless of whether it is a magazine cover, cardboard package (such as cereal boxes) or can labeling, etc. and transports its stock from manufacturing to shipping / receiving (such movement within the truck or conveyor rubs them against each other) in the self-service warehouse (which requires handling between the shelves) and finally to the consumer who chooses the products of according to your appearance. - • The test provides smearing of a clean substrate (paper material) in. ufi "printed material normally using a weight of 1.82 kg The weight was placed to impart strokes, which is a back and forth movement, to cover the paper material and impart 50 strokes. The results are shown in Table 2. The results were determined through visual inspection and compared with the standard one. The visualization was based on the visual observation of the amount of ink transferred to the paper substrate.The types of resistance were graded as follows: Wear resistance / deterioration Excellent (almost without emborning) 5 Good 4 Average 3 Below average '• - 2 Poor 1 TABLE II Discussion of results: The additives of the invention deployed almost without smearing and excellent results compared to the standard. The inventive inventive samples in fact had little or no blurring. The standard had a highly visible blurring. Example 4 A number of 'tests for sliding measurement were executed. This test was. to show the reason for the frictional force that resist the movement of the surface being tested to the normal force applied to the surface. The apparatus used was a sled or metal block harrow with a flat surface block of '5.08-10.16 cm (2-4") and a plane at an angle of 45 ° at a ratio of 1.5 ± 0.5 ° / S. weight was attached to a gauge or indicator to indicate the speed at which the weight slides on the substrate.The resistance to sliding carries a major problem of importance for an anti-abrasive additive, its test work together with the anti-abrasive test. If the slip is poor, for example, a scientist expects the additive to also have very poor smear resistance, it will also indicate static that can cause printing problems, if the slip resistance is below average, for example , it could cause the sheets of printing paper inserted in the magazine to adhere to each other, which is undesirable, and is unacceptable to a publicist.Table III shows that the additives of the invention have excellent slippage in Comparison with a standard product. The parameters of the test result were graded as follows: Resistance (angle 0 ') al- slip Excellent 15-17 Good '18 -20 Average 21-23 Below the average 24-26 Poor 27 onwards The cloudiness tests were also executed using state-of-the-art techniques. Cloudiness or cloudiness occurs when the additive in the finished formulation is printed in a printing press. When this happens, the print cylinder stains with a fine spray that transports to the other printing cylinders. Most ink manufacturers add a fibrous additive to compensate for this problem. As can be seen from Table III, the additives of. the inventive end with this problem. The test results were as follows: Cloudiness Excellent 0% Average. "1-5% Poor 6% onwards TABLE III The foregoing background, description and examples have been disclosed only to illustrate the invention and are not intended to be limiting. Because many modifications and simple changes to disclosed embodiments that incorporate the spirit and substance of the invention can occur to persons with skill in the art, the invention must be constructed to include everything within the scope of the appended claims, its obvious equivalents and variations of it.

Claims (21)

1. CLAIMS; An anti-abrasive additive for ink formulations, comprising: a) from about 40 to 70 parts by weight of sintered polytetrafluoroethylene; and b) from about 30 to 60 parts by weight of one or more pharmaceutical grade petrolatums.
2. 2. The additive according to claim 1, wherein the polytetrafluoroethylene has been irradiated.
3. 3. The additive according to claim 1, wherein the polytetrafluoroethylene. it has an average particle size of about 2 to 10 microns 4. The additive according to claim 3, wherein the polytetrafluoroethylene has an average particle size of about 2 to 5 microns. additive according to claim 2, wherein the polytetrafluoroethylene has an average particle size of about 2 to 5 microns 6. The additive according to claim 5, wherein the average particle size resulted from the microminium-turization of the The sintered and irradiated polytetrafluoroethylene 7. The additive according to claim 1, wherein the polytetrafluoroethylene is a virgin granular powder 8. The additive according to claim 1, wherein one or more of the pharmaceutical grade petrolatum meets FDA requirements of 21 CFR 172.880 9. The additive according to claim 8, wherein one or more of the pharmaceutical grade petrolatum has a gravity. ad specific 60 ° C / 25 ° C between 0.815 and 0.880. The additive according to claim 1, wherein one or more of the pharmaceutical grade petrols contains less than 2% oil. 11. The additive according to claim 1, wherein one or more of the pharmaceutical grade petrolatum is Witco Protopet IS. 12. An anti-abrasive additive for ink formulations, comprising: a) from about 30 to 60 parts by weight of sintered polytetrafluoroethylene powder; b) from about 25 to 45 parts by weight of one or more pharmaceutical grade petrolatums; and c) from about .5 to 15 parts by weight of one or more petroleum oils; and d) from about 5 to 1.5 parts by weight of one or more resins selected from the group consisting of hydrocarbon resins and phenolic resins. 13. The additive according to claim 12, wherein the polytetrafluoroethylene is a virgin sintered powder with a size of. average particle of approximately 2 to 5 microns. 14. The additive according. with claim 12, wherein the average particle size resulted from the microminiaturization performed by grinding the sintered polytetrafluoroethylene. 15. The additive according to claim 12, wherein the polytetrafluoroethylene is an irradiated and sintered powder. 16. The additive according to claim 12, wherein the polytetrafluoroethylene has been irradiated during the sintering. 17. The additive according to claim 12, wherein the polytetrafluoroethylene is a virgin granular powder. 18. The additive according to claim 12, wherein one or more of the pharmaceutical grade petr-olates meets the requirements of. FDA 21 CFR 172.880. 19. An anti-abrasive additive for ink formulations, comprising: a) from about 40 - to 70 parts by weight of irradiated and sintered polytetrafluoroethylene of an average particle size of about 2 to 10 microns; and b) from about 30 to 60 parts by weight of one or more pharmaceutical grade petrolatums. 20. An ink formulation containing from about 0.1% to 10% by weight of an anti-abrasive additive comprising: a) from about 40 to 70 parts by weight of sintered and irradiated polytetrafluoroethylene; and b) from about 30 to 60 parts by weight of one * 'or more pharmaceutical grade petrolatums. 21. An ink formulation containing from about 0.1% to 10% by weight of a pumpable anti-abrasive additive comprising: a) from about 30-5 to 60 parts by weight of sintered and irradiated polytetrafluoroethylene; and b) from about 25 to 45 parts by weight of one or more pharmaceutical grade liquid petrolatums; and c) from about 5 to 15 parts by weight of one or more petroleum oils; and d) from about 5 to 15 parts by weight of one or more resins selected from the group consisting of hydrocarbon resins and phenolic resins. r ^ átíí EXTRACT An additive for sliding / anti-abrasive ink comprising a mixture of polytetrafluoroethylene and pharmaceutical grade petrolatum is disclosed. They can be added to the mixture as an additional alternative material, such as phenolic resins and oils. The additives allow for the lower manufacturing cost of printing inks, more particularly the -thin-colored inks and results in printing having improved slip, anti-spoilage and wear characteristics. S