DE1052891B - Process for decorating objects with ceramic colors - Google Patents

Description

Method of decorating objects with ceramic paints The Invention relates to the application of ceramic decorations, in particular the decoration of objects with ceramic colors using the screen printing technique using multiple prints.

The application of ceramic decorations, e.g. B. of glass colors that consist of inorganic pigments and finely ground glass on ceramic bodies (Glass, porcelain, etc.) and metal objects using the screen printing or stenciling technique has been used for a long time. This method of decorating glass objects is becoming almost universal in the beverage and milk bottle industry these days and to a considerable extent in the furnishing of water glasses and similar objects used. In practice, one is generally used today as a screen printing ink Dispersion of the enamels in an oily vehicle containing a volatile solvent. This type of carrier has been used successfully for years for the manufacture of screen printing inks used, but if a multicolored ornament is to be achieved each must Print except for the last to be dried to the volatile solvent remove and fix the print before applying the next print can without smearing. After printing, the ornament will be then branded on the object.

After a recently introduced change in screen printing technology one uses a carrier that is solid at normal temperatures, but for something elevated temperature is liquid during application. The use of such Carrier has the advantage that the hot carrier immediately upon contact with the cold object becomes solid and thus between successive prints no drying has to take place. If, however, one prints for all single prints when printing multiple times If such a high-melting carrier is used, there is a risk that through the heat developed during the subsequent printing of the previously applied layers to be damaged. With the method according to the invention these difficulties become apparent completely eliminated or substantially reduced in size.

The invention relates to the development of a method of decorating of ceramic objects or glass. It also aims to improve application ceramic decorations using the screen printing or stenciling technique, in which more than one print is applied and the removal of the solvent off an imprint by using dryers to make this before applying the solidifying the next print becomes completely unnecessary. Other advantages and Purpose information emerges from the following description.

These objects are achieved according to the invention by on a base body, in particular made of ceramic, glass, porcelain or the like, one or applies several prints of a ceramic color mass, which consists of a dispersion of a ceramic paint in a carrier of the type described below and which, upon contact with the base body, form a firmly adhering coating solidified, and - without intermediate drying or firing of the print (s) - applies the last imprint using another ceramic color compound, which consists of the dispersion of a ceramic paint in a carrier, which is a contains volatile solvent and then burns in the printed decoration.

The color mass or masses used to apply all of the color mass or masses used with the exception of the last coating or print is applied to the object using the known screen printing or stenciling technique. These masses are dispersions of ceramic colors, such as finely ground mixtures of inorganic pigments and glass, in a carrier which (a) 30 to 80% of a substance which melts at 49 to 110 ° C, e.g. B. a wax, a wax mixture or a mixture of a wax or waxes with a wax-like substance, (b) 1 to 10% ethyl cellulose, (c) 14 to 68% rosin, a rosin derivative or mixtures of such substances, (d ) 0.5 to 10% of an organic phosphate, such as lecithin or phosphorous tail oil, and (e) 0 to 1% pyrogallic acid. Dispersions of finely ground ceramic paints in such a carrier in a ratio of about 2 to 6 parts by weight of ceramic paint per part by weight of carrier represent coating compounds that are solid, essentially non-volatile at ordinary or normal temperature and are made by stenciling according to the screen printing technique at a temperature in the range of 49 to 110 ° C can be easily and effectively applied to the object to be decorated. At these temperatures the masses are pastes or paints, and when applied to a body of ordinary temperature they solidify almost immediately to form firm, adherent coatings that do not need to be dried or baked before the next print is applied. The body to which such a hot mass is applied does not need to be at room temperature, but its temperature should be at least about 8 ° C. below the melting temperature of the mass applied. In practice, however, the article is usually around room temperature.

In terms of the mass for applying the first, ie all prints with the exception of the last, not all supports which melt in the range from 49 to 110 ° C. are suitable. In order to be suitable, a carrier must produce a screen paste or paint which can be processed at about 49 to 110 ° C., ie it must not thicken or gel for a long time at the application temperature, its viscosity must not change significantly at such temperatures change, it must not clog the stencil and should have suitable flow and leveling properties. This means that the carrier should be essentially non-volatile at the working temperature, but should volatilize quickly enough on firing to prevent the color from running off. Furthermore, when applied to the cold object, the carrier must immediately solidify to form a firm, smooth, tough, adherent coating which is resistant to normal abrasion and impact and which upon firing gives a low carbonaceous residue. The stickiness of the carrier must be sufficient to bind the print to the object, but must not be so great that on the underside of a subsequent stencil, e.g. B. in liver storage of color prints, a previous print sticks. The support should give prints that are neither too hard nor too soft; Prints that are too hard break easily when handling the object, prints that are too soft are easily scratched, stained and destroyed. It has been found that a carrier, as described above, must contain certain components or types of components in certain amounts in order to meet these requirements.

The final stage of the application of the ornament is carried out according to the Invention using a dispersion of a ceramic paint in a carrier, which at normal temperature is not solid, but paste-like or liquid. Such carriers are e.g. B. the hitherto usually used for the application of ceramic colors used carrier. In contrast to the high-melting points described above Carriers or masses are referred to below as "air-drying" carriers, and when ceramic paints are dispersed in them, the resulting mixtures will referred to as "air-drying masses", since by removing the solvent, d. H. "Dry" in air, in a dryer or in an oven.

The final coating with the dispersed in an air drying vehicle Ceramic paint can be done by various methods including spraying and Brushed on, applied, preferably brought by the screen printing technique on. Suitable for applying this last imprint using the screen printing technique Air drying carriers usually contain in addition to a volatile solvent Binding agents, additives increasing the viscosity and dispersing agents. Preferred however, air-drying carriers of the following composition: (f) 50 to 80% of one volatile solvents, generally of the terpene or petroleum type, such as terpene ethers, Terpene alcohol and the aromatic and paraffinic hydrocarbon solvents, (g) 15 to 35% rosin or rosin derivatives or mixtures of such substances, which serve as a binder, (h) 0.5 to 7% ethyl cellulose, which acts as a viscosity-increasing agent Additive and hardener is used, and (i) 0.5 to 10% of an organic phosphate, such as lecithin or phosphorous tall oil, which serves as a wetting agent. These wetting agents are the most effective in amounts of about 4 to 10% in the case of lecithin and 0.5 to 7% in the case of phosphorous Tall oil, the latter being preferred. Other substances can also be used be present in smaller proportions.

Table I gives the composition of five preferred high-melt type supports that are particularly useful for applying all but the last coating, while Table II gives the composition of six preferred air-drying supports for screen printing the final coating. Table II Air drying carrier Preparation PGHI f Polymerized abietic acid ......... 7.98 15.00 - - 10.03 10.10 Hydrogenated rosin ............ 13.60 6.58 20.10 21.11 11.03 11.10 Ethyl cellulose ....................... 2.28 2.28 3.30 2.39 3.21 0.86 Diet hyloxalate ....................... 3.28 3.28 3.50 3.66 3.67 3.70 DL-Malic Acid .................. ..... 0.18 0.18 0.20 0.18 0.18 0.18 Terposol No. 3 ... .. ................. 12.98 12.98 - - 48.44 - Spruce oil ........................... - - 30.00 31.23 16.11 73.31 Petroleum solvents .................. 51; 96 51.96 35.60 - - - Boric acid ............................ - - 0.40 0.37 - - 10% solution of 85% ortho- phosphoric acid in spruce oil ........ 1.73 1.73 - - 6.62 - Diesel oil ... .. ........................ - - - 36.82 - - Phosphorized tall oil ................ - - - - 0.76 0.75 Lecithin ............................ 6.01 6.01 6.90 4.24 - - Terposol No. 3 used in some of the above formulations is a commercially available terpene solvent which is described as a terpene ether obtained by reacting a terpene hydrocarbon with methanol. The petroleum solvent used in some of the above compositions is a commercially available aromatic hydrocarbon type solvent.

The air-drying supports of Table II can be made by making a mixture of the ingredients with the exception of the spruce oil solution of phosphoric acid and the lecithin or phosphorous tall oil to a moderately high temperature, e.g. B. about 90 ° C, heated to homogeneity. The mixture is then cooled down a little, z. B. to about 41 ° C, sets the remaining ingredients and stirs the whole Approach to homogeneity. Screen printing inks are made using such carriers made by mixing 2 to 6 parts of glass enamel with 1 part of carrier and the Mixture passes through a roller grinder or other device, as is customary Used to disperse ceramic pigments in carriers to ensure uniformity To produce color.

The refractory supports of Table I can be made by phosphorating a mixture of the ingredients with the exception of the lecithin Tall oil and pyrogallic acid to homogeneity at elevated temperature, e.g. B. about 130 ° C, heated. Then you add the remaining ingredients and stir the entire batch at approximately the same temperature until homogeneous. Screen printing inks or pastes are prepared using these carriers by adding 2 to 6 parts of glass enamel mixed with 1 part of carrier and the mixture through a roller grinder Od. Like. Conducts to produce a uniform mass. The mixture is during this processing is usually kept at a temperature of about 80 to 110 ° C. The paste or paint can then be used directly or poured into a shallow pan by allowing them to solidify and then slicing them into pieces for shipping or storage breaks.

The following examples explain the use of various the above-described carrier for the application of ceramic decorations according to the invention on glass objects. In all cases the colors are using 2 to 6 parts of glass paint produced per part of carrier. Example 1 One by dispersion a glass color in the high-melting base D of Table I made is applied to glass objects using a stencil using the screen printing technique. The glass objects are at room temperature, while the color during the application is kept at 49 to 110 ° C. In the same way you bring one second imprint, which is not superimposed on the first, using a glass paint made with Air Drying Support F of Table II. At the second time Imprint, both the glass object and the color are at room temperature. The printed object is then fused in the usual manner the coating is fired with the glass at the necessary temperature. When applying the second print no difficulties arise; it will be an excellent one Ornament received.

Example 2 The procedure according to Example 1 is repeated with the exception that the second imprint is superimposed on the first imprint and becomes the second imprint a paint is used which is obtained using the air drying backing J of Table II is prepared. Excellent decoration is obtained; when applying the second print does not damage the first. Similar results are obtained when the color for the second or superimposed overprint is below Using the air drying carrier H, I or K of Table II is made.

Example 3 The general procedure of Example 1 is repeated with the exception that three prints are made on the object. To the Production of the color for the first two prints, the second on the first is applied, the high melting point carrier B is used. To manufacture the Color for the last imprint, which is superimposed on the first two imprints, the air-drying carrier G is used. When applying the second and third imprint, no damage to any imprint occurs, and after After baking the prints, an excellent coating is obtained. The same Results @verden received when you go to manufacture the color the air-drying carrier I c-used for the last print.

Example 4 Example 1 is repeated except that the color for the first print using the high melting point carrier A and the Color for the second imprint superimposed on the first using of the air-drying carrier G is made. An excellent one is obtained after stoving Ornament. Essentially the same results are obtained using the The high-melting-point carrier C is used to produce the color for the first imprint.

The ceramic masses referred to as colors in the examples are generally made by applying the ceramic paint, e.g. B. a finely ground Mixture of inorganic pigment and glass, either in the refractory or the air-drying carrier in the proportion of about 2 to 6 parts by weight per part Suspended or dispersed carrier, usually in a weight ratio of about 4: 1 is used.

The wax used in the high melting point carrier, wax mixture or mixture of wax and wax-like: material should be at a temperature in Melt range from 49 to 110 ° C and about 30 to 80, preferably 40 to 60% of the wearer. Examples of suitable waxes and wax-like substances, which are used either alone - in the case of certain waxes - or in a mixture can in order to melt a material in the required temperature range received are paraffin, carnauba wax, spermaceti, beeswax, cana wax (cf. Table I), microwax, palmitic acid, stearic acid and solid soaps.

The ethyl cellulose content of the high-melting point carrier should not be less than about 1% still more than about 10%, is preferably 1 to 5 and in the preferred air-drying carriers about 0.5 to 7%. The ethyl cellulose is used to increase the viscosity or as a thickener and also as a hardener. In each Carrier type can use ethyl cellulose of low, medium and high viscosity but it is generally preferred to use a medium cellulose Viscosity.

The rosin or rosin derivative is said to be in the high melting point Carrier in an amount of 14 to 68, preferably 35 to 55% can be included in the preferred air-drying carrier in an amount of 15 to 35%. These substances serve as hardeners in both types of carrier and support the adhesion of the print on the object. You also make the ethyl cellulose with the wax component of the high-melting point carrier is easier to mix. Examples of these substances are Rosin and abietic acid, rosin and abietic acid esters, such as methylabietate, polymerized rosin and polymerized abietic acid, hydrogenated rosin and hydrogenated abietic acid and the metal salts of rosin and abietic acid, z. B. zinc, titanium and calcium salts. The hydrogenated rosin is particularly preferred.

The high-melting carrier must contain 0.5 to 10% of an organic phosphate, such as soy lecithin, heat treated or "cooked" lecithin, and phosphorous Contain tall oil. One or both of these phosphate substances serving as wetting agents is also included in the preferred air-drying carriers in one Amount from 0.5 to 10%. In both types of carriers, lecithin is preferably used in one Amount of 4 to 10% used, while the phosphorous tall oil is preferably used in an amount of 0.5 to 7.0% is used. The phosphorous tall oil is preferred.

The pyrogallic acid is not an essential part of the high melting point Carrier. It seems, however - z. B. in concentrations of 0.01 to 10/0 - in In some cases, it may be desirable to prevent the hot carrier or the Color to prevent. Furthermore, it is in the case of the preferred air drying carriers it is often desirable, though not essential, to have small amounts of other ingredients are present as the formulations of Table II show. For example for those other substances, the presence of which may be desirable, to prevent the screen printing inks from gelling during manufacture or storage, and the concentrations in to which they are generally used are diethyloxalate (1 to 5%), DL-malic acid (0.1 to 1o4), boric acid (0.4 to 0.6%) and a 10% solution of 85% orthophosphoric acid in spruce oil (1 to 10%).

The inventive use of a high-melting carrier for Application of all prints with the exception of the last and an air-drying carrier for applying the last pressure is unique of its kind and produces pronounced and significant advantages over methods in which one of the two types of carrier is used solely to apply all prints. An important advantage lies in that the dryers common to all air-drying multiple prints no longer need to be used. Another important benefit is that the method according to the invention, the fixed clamping of the object in an automatic decorating machine for all color prints, thus making the concealment the multicolor printing simplifies and the need to put one of the to attach previously customary fitting ribs is omitted. By the method according to the invention Furthermore, stencil and color no longer need for the last print on the heightened Temperature to be maintained, what when using high melting point masses for everyone Prints would be necessary. Further, the amount of carbonaceous material that is in the Heat treatment zone has to be burned down compared to all hot prints. Finally, there is less chance of damaging previous prints, if the last imprint is applied at room temperature instead of at elevated temperature. If only two prints are applied, the method according to the invention the first print is not damaged by a subsequent hot print.

Unless otherwise stated, percentages relate to the Total weight of the carrier or the coating mass.

Claims (6)

PATENT CLAIMS: 1. Method of decorating objects Ceramic, glass and the like with ceramic colors by multiple screen printing, characterized in that that on the object whose temperature is at least 8 ° C below the melting temperature must lie with the color to be applied, all prints with the exception of last using a non-volatile and solid at room temperature 49 to 110 ° C melting paint applied in a known manner will, then as the last imprint a liquid at room temperature, per se known air-drying paint that contains a volatile solvent and Only when it is volatilized does it solidify, is applied and finally the imprints to be burned in. 2. The method according to claim 1, characterized by the use a high-melting color mass as a dispersion of a finely divided ceramic Color in a carrier that (a) melts 30 to 80% of one in the range of 49 to 110 ° C Wax, wax mixture or mixture of wax and a wax-like material, (b) 14 to 68% rosin or abietic acid, rosin or abietic acid ester, polymerized rosin or polymerized abietic acid, hydrogenated rosin or hydrogenated abietic acid, or metal salts of rosin or abietic acid, (c) 1 to 10% ethyl cellulose, (d) 0.5 to 10%. an organic phosphate of Contains class lecithin and phosphorous tall oil and (e) 0 to 10 / ü pyrogallic acid. 3. The method according to claim 2, characterized by the use of a carrier for the high-melting color mass from component (a) in an amount of 40 up to 60%, the component (b) in an amount of 35 to 55%, the component (c) in an amount of 1 to 5%, the Be component (d) in an amount of 0.5 to 7%. and the component (e) in an amount of 0 to 10 / a. 4. The method according to claim 1 to 3, characterized by the use of an air-drying paint mass as Dispersion of a finely divided ceramic paint in a carrier which (f) 50 to 80% of a volatile solvent, (g) 15 to 35% rosin or abietic acid, Rosin or abietic acid ester, polymerized rosin or polymerized Abietic acid, hydrogenated rosin or hydrogenated abietic acid, or metal salts of rosin or abietic acid, (h) 0.5 to 7% ethyl cellulose, and (i) 0.5 to Contains 10% of an organic phosphate of the class lecithin and phosphorous tall oil. 5. The method according to claim 1 to 4, characterized by the use of a high-melting point and / or air-drying paint that contains 2 to 6 parts by weight of ceramic paint each Contains carrier part. 6. The method according to claim 1 to 5, characterized in that that the color compositions are applied to an object that is at room temperature will. References considered: British Patent No. 616,827.