DE880801C - Process for the production of tablet-shaped objects from rubber milk - Google Patents

Description

Process for making tabular articles from rubber milk the Invention relates to the manufacture of sheet-like articles from latex.

Such panel-like objects have already been proposed by depositing latex on solid forms of the desired shape.

However, such shapes are expensive to manufacture. Also is in the case of mass production, a large number of the same shapes are required. According to this older process, the deposited objects are usually exposed the molds dried or vulcanized. So it's not just institutions here required for dipping the molds into the latex, it also has to be Means are provided to guide the molds to drying or vulcanizing equipment and to be able to remove them again.

It has also been suggested that endless metal belts should be used or the like to deposit a sheet made of latex. However, this can only be done from one side of the hinge a practically applicable latex layer can be obtained. In addition, the so seasoned must Latex layer can be separated from the conveyor belt before being converted into the desired items appropriate shape can be cut. Sheets of latex deposited in this way tend to curl very easily. Furthermore, due to its elasticity, there is also the Danger of them stretching during the cutting process. It is therefore after this Procedure, especially in the case the processing of very thin latex, difficult to obtain panels of uniform shape and outline.

It has also been proposed to use rubber or latex cloths to be coated or impregnated. This is where the rubber or latex penetrates so strongly into the cloth that it can practically no longer be separated from it.

According to an older process, the latex articles become hers Vulcanization usually exposed to hot air. Such completely in hot Objects vulcanized in air feel relatively rough. After a Another known method is to make the latex articles by dipping them in boiling Water vulcanized.

In the case of such treatment with hot water, however, appears easily dissolved or leached some of the accelerator contained in the latex to become. This results in a somewhat mushy structure, only a minor one Durability and rapid aging of the vulcanized latex.

According to the invention, the proposal is made to apply latex layers one or both side surfaces of a cuttable metal foil, for example an aluminum foil, which is responsible for the latex not only during the deposition the latex layer or layers, but also during vulcanization as well as during cutting the latex layer or layers into the desired articles Outline serves as a carrier. The metal foil thus forms a carrier through which one Stretching of the latex layers is prevented during the cutting process. After this the latex layers together with the metal foil in the desired size and shape have been cut, they are cut from the resulting metal foil blanks, on which they have previously been deposited, separately.

The metal foil used to support the latex layers can optionally be used on one or both surfaces with one or more sheets of paper or the like. be covered. Furthermore, if necessary, a corresponding one can first be applied to the metal foil Acid or an alkali can be applied this way the latex on the film to be able to coagulate.

According to a further feature of the invention, the latex articles first precured by hot air or gas, so that the contained in the latex Accelerator can no longer be released from it, whereupon the so pre-vulcanized Objects are vulcanized in hot or boiling water. It has shown that with such a combined application of hot air and boiling The objects obtained in this way neither have the roughness of just in water objects vulcanized in hot air still have the softness of just hot water vulcanized objects, but rather feel somewhat velvety.

The articles made in this way are also of high quality Quality and also have excellent wear and aging properties.

Other objects and features of the invention will appear from the following Description of an embodiment illustrated in the drawing, namely, Fig. I shows a schematic representation of the method of production of latex articles, Fig. 2 is a pictorial representation of one of the desired Dimensions having cut piece of the used according to the invention flexible metal foil with applied latex layers; the individual latex layers are shown as partially withdrawn from the mold, Fig. 3 shows a section the line 3-3 of Fig. 2 showing the nature of the latex layers at the edges Fig. 4 shows a schematic representation of a modification form the device for carrying out the method, FIGS. 5 and 6, cross-sections through two different versions of the according to one of the methods according to FIG flexible metal foil coated with latex, Fig. 7 is a plan view one after the other Process made tabular latex article, Figure 8 is a schematic Representation of a modification of the device for depositing a latex layer onto a metal foil strip, FIG. 9 shows a section through part of a foil strip, on which a latex layer has been applied with the device according to Fig. 5, 10 is a diagrammatic representation of a device for simultaneous generation several rubber strips or threads of relatively great length, Fig. II a section one covered on both sides with rubber and partially cut into several strips Blackboard; the end sections of the rubber layers shown as peeled off from the film strip are not cut up, Fig. I2 is a schematic plan view of that part the device according to Fig. Io, which serves the rubber layers with their metal foil to cut up the rubber strips produced in this way from the strips of metal foil to separate and wind the rubber threads on several bobbins, Fig. 13 is a side view the cutting or separating knife in its working relationship with a support roller during of cutting up the metal foil and the layers applied to it, Fig. I4 is an end view of FIG. I3, FIG. 15 is a side view of a schematic Representation of a modification of the device for winding the won Strip of a layer with only one coil, FIG. 16 shows a plan view of FIG. 15.

According to Fig. I is a roll R of an impermeable cuttable metal foil, preferably aluminum foil on a rotatable support 5 corresponding arranged in order to be able to unwind the metal foil 6 therefrom. For handling the Metal foil 6 from the roll R serves a pair of conveyor rollers 7, which are expedient by a device known per se (not shown) with a constant Speed are driven and the film 6 at a uniform speed to a lidless container T which is a bath of liquid latex, for example an aqueous rubber dispersion contains. The side walls of the container T carry a suitable roller-shaped guide G, under which the advancing metal foil 6 is passed through. The film 6 moving through the latex bath is Covered with a latex layer on both sides when they emerge from the bathroom be. After the advancing, now designated 8 SIetallfolie on has been coated with latex in this way, it is passed through a drying oven g, in which the latex layers applied to the tape are dried. from the drying oven g reaches the metal foil 8 provided with a coating with their previously dried layers with the interposition of one, preferably with the same peripheral speed as the conveyor rollers 7 driven roller 10 in a vulcanizing device II, in which the latex layers of the tape are partially to be vulcanized. One with the same peripheral speed as the conveyor rollers 7 and the guide rollers Io driven roller I2 guides the coated metal foil 8 to a pair of revolving conveyor rollers 13, which are also with the same Peripheral speed as the rollers explained above are driven.

The conveyor rollers 13 lead the coated metal foil 8 over a Guide roller 14 to a container 15 with hot water, in which the vulcanization the latex is completed. To cover the bedeclite film with a consistent To be able to move speed through the hot water are in the container 15 corresponding guide rollers I6, 19 are provided. If necessary, the Container 15 also have two additional guide rollers I7, 18 arranged. The coated metal foil 8 passes over from the hot water of the container 15 a guide roller 20 between a pair of driven in any desired manner Felt rollers 21 and 22. The felt rollers 2I and 22 are not only used to convey the coated metal foil 8, but rather also the ones facing them Surfaces of respective containers 23 and 24 with a powder agent such as talc, to pollinate. This is done in such a way that the felt rollers 21, 22 from the containers 23, 24 are continuously supplied from small amounts of talc. After their pollination the coated metal foil 8 is wound up again into a roll 25. Since the Latex layers of the covered metal foil 8 have been vulcanized beforehand, For example, the roll 25 can be stored for as long as desired until it is used. However, it can also be used directly in various table-shaped objects, such as tablecloths, Rubber sheets or the like, are further processed.

The latex layers of the coated metal foil 8 are in the device II precured by being exposed to for a period of 15 minutes be exposed to hot air or hot gas with a temperature of up to II50 C. This prevents the latex from being stolen. After that the latex layers exposed to the action of hot and expediently boiling water until the vulcanization process has ended.

In the manufacture of individual objects from the coated metal foil 8 this is unwound again from the roll 25 and into individual pieces of the desired Shape cut up; the metal foil 6 and its layers become the desired ones Pattern cut out. Here, the film 6 serves as a flexible, easily cutable one Carrier for the latex layers, designated 26 and 27 in FIG. 2, adhering to it, in order to achieve in this way that the layers 26 and 27 easily into the desired Shape can be cut without the risk of curling or warping consists. After cutting the coated metal foil 8 into the desired Pieces are peeled off the latex layers 26, 27 from the carrier film. Through this two objects can be achieved at the same time in one work sequence.

As can be seen from Fig. 3, the latex layers 26 and 26 run 27 at the edges of the foil. This results in a separation of the two the layers deposited on the metal foil are made much easier by tearing them off.

In FIG. 4, a modification of the method according to FIG of the invention for making latex tabular articles. In this embodiment a roll R of aluminum foil is in a container 3I immersed, which is a bath of liquid latex, for example an aqueous rubber dispersion, contains. The role R can optionally also be only partially immersed in the bath be. The only requirement is that the metal foil is actually used when it is being processed rising from the bathroom. The roller R is preferably mounted on a carrier 32, which is rotatable in corresponding rails 33 on the end walls of the container 3I. Following the procedure shown here, the metal foil is rolled at a uniform speed unwound from roll R and emerges from the latex bath in the form of one on top of both Sides with tape 34 each covered with a uniform latex layer.

The belt 34 moves appropriately after emerging from the bath vertically upwards through a chimney-shaped heater 35, the walls of which in some usual way heat is added to this way the surface of the rising covered leaf into a uniformly rising column at hotter Enveloping air or hot gas and thus the latex layers of the coated tape to dry and to partially vulcanize. The length of the chimney-like Heater 35 is expedient to choose so that the latex layers of the coated Belt 34 when leaving its vertical conveying path already dry and partially are vulcanized. After exiting the heater 35, the coated tape becomes 34 passed to reverse its direction of movement via guide rollers 36, from where it descends at a steady rate into a container 37 of hot and preferably moving boiling water, in which the vulcanization of the latex layers is carried out to the end. The movement of the belt 34 through the container 37 is regulated by the guide rollers 38. After the last guide roller 38 emerges the coated tape 34 back up from the hot water by stretching it over the Guide rollers 39 after a pair of revolving dusting rollers 40 and 41 emotional. The surfaces of the dusting rollers 40 and 4I received from the containers 42 and 43 corresponding amounts of talc or a similar powdering agent. Through this is a uniform dusting of the rollers 40, 41 facing surfaces of the coated Volume 34 reached. After leaving the pollination rollers 40, 41, the covered tape 34 on a guide roller 44, from where it is either driven by a motor M wound up into a roll 45 or processed directly into individual latex articles will.

As already explained in connection with the roller 25 according to FIG is, the roll 45 can be stored until it is further processed.

The covered band 34 is simply used again for further processing unwound from roll 45 and cut into the desired pieces and shapes such as the tablecloths 46 shown in Fig. 7, cut up. Those shown in FIG Tablecloths 46 each have an incised slot 47 at their ends. the Slots 47 are used to accommodate the matching corners of the table top which the ceiling in question is to be opened. In the manufacture of such tablecloths is proceeded according to the invention in such a way that the coated tape 34, which to both sides are covered with a layer of latex, initially at the same time Cutting the incised slots 47 into individual pieces of the FIG. 7 is cut in the form shown, whereupon the individual layers become both Pages of the tape 34 can be pulled off this. That way you can two items of tablecloths produced at the same time in a single work sequence will; are the resulting foil blanks when peeling off the layers, because they are no longer applicable for any further work processes, to be thrown for waste.

Nevertheless, according to the method described above, by depositing of latex layers 48 and 49 on a supported sheet of foil, for example on the metal foil 6 of Figs. 1, 2 and 3 or the tape 34 of Fig. 5, excellent Let latex panels reach, a coating could also be placed on the band 34 (FIG. 6) 50 made of porous paper, for example with the properties of blotting paper, can be applied. As has been shown, when a metal foil is used, together with another one Covering of porous paper on the bare surface of the film a thinner latex layer 51 from when the latex layer 52 corresponds, which is on the free surface of the porous Paper is deposited. By employing a form of the nature shown in FIG can thus on the opposite sides of a moving bendable one Tape or carrier deposited two layers of latex of different thicknesses at the same time will.

According to the modified method illustrated in FIG the flexible tape to be treated with a latex layer only on one side overdrawn. According to this method, a metal foil 53 or a foil is made and tape composed of a paper layer unwinding from a roll R with its lower surface on the latex tape 55 of a corresponding container 56 lying under the guide roller 54 passed through. If the slide 53 of the Roll R unwound at a precisely determined speed, so does not need Guide roller 54 to be arranged, as in this case the surface tension of the bath would suffice to cover the underside of the film with the latex surface keep in touch to apply the latex. Through this coming into contact with the bath, the foil strip 53, now designated so-called, is on its underside coated with a latex layer 57. After applying the latex layer to the Tape 53 this is dried in one of the devices according to FIGS and vulcanized. This can now be done with a vulcanized latex layer provided band 58 after its pollination to a later further treatment Roll to be wound up. If necessary, however, it can also be done immediately afterwards corresponding individual pieces are cut up in any pattern, whereupon just close the latex layer from the individual cut foil blanks separate is.

As can be seen from the foregoing description, the latex layers mechanical, d. H. by immersing the film in a latex bath, followed by Drying to be applied.

If necessary, however, they could also be done by allowing the latex to clot can be obtained on the slide. In this case, the foil is before its immersion in the latex bath in a known manner with acid or alkali. Furthermore, the liquid latex can also be in the unvulcanized or vulcanized state be used.

If vulcanized latex is used, it needs to be applied to the foil deposited latex layer only needs to be dried, whereas another one Vulcanization of the layer is not required.

The thickness of the layer can basically be changed by changing the number the successive dipping and drying processes, the violence of Gerinuvorganges or the nature of the absorption material applied to the film or regulated by any combination of the above change options will.

For the production of elastic threads, the covered band can after its passage between the pollination rollers 21 and 22 (Fig. I) or 40 and 41 (Fig. 4) inserted between the guide rollers 125, 126 and thence between the conveyor rollers I27 will. In FIG. 10, the covered metal foil is again designated by 8.

The film strip passes from the conveyor rollers 127 between the cutting roller 128 and the back-up roll I29. As can be seen most clearly from FIGS is, the cutting roller 128 consists of several seated on a drive shaft I3I Round knives 130 which are seated on a drive shaft 131. The width of the generated Threads become more adjacent due to the distance between the cutting edges Knife I30 determined. The knife edges of the cutter roll come with the surface the support roller 129 seated on the drive shaft I32 in contact. The surrounding area the support roller 129 is therefore to be covered with a substance that the cutting edges the knife does not dull and the covered foil tape is still strong enough holds against the knife. Such a coating could be, for example, rubber des correct degree of elasticity are used.

The over-drawn metal foil 8 arrives after leaving the cutting roller 128 between the driven rollers I33, which are useful in relation to the conveyor rollers 127 are driven at such a speed that the covered film during the Cutting process is under a bias. The rubber deposited on the film is made a little stronger before the cutting process, as shown. This is because of this achieves that the coated metal foil 8 passed through a chamber I34 containing a refrigerant such as solid carbon dioxide. However, the invention is not limited to cooling the covered tape prior to the cutting operation. After the tape has been cut, the individual rubber threads must be removed from the associated Strips of the carrier film are separated.

For this purpose, the strips of aluminum foil are used to transfer them into a waste bin (not shown) between a pair of conveyor rollers I35 passed through. The ones created by cutting the top rubber layer Rubber threads Sa come into contact with the peripheral surface of a large roller I36, from where they get between the conveyor rollers I37.

The roller I36 and the conveyor rollers I37 are advantageous with a to drive slightly greater speed than the conveyor rollers 133, so that the Rubber threads are subjected to a bias, while the strips of aluminum foil stay relaxed. This allows a separation of the rubber threads from the Reach strips of foil. In a similar way, they arrive by cutting threads 8i formed of the lower rubber layer on the periphery of a large roller 138 passing between a pair of conveyor rollers 139, which have the same effect as the Roller I39 and the conveyor rollers I37 have, in this way, to move the individual rubber threads, in which the lower rubber layer has been cut from the film strips to separate. Each of the upper rubber threads wound on a special reel 140.

The coils I40 expediently run at the same speed like the conveyor rollers 137 um.

This ensures that the threads do not during their winding up to be under tension. Similarly, those from the lower layer are made formed threads on also at the same speed as the conveyor rollers I39 powered special bobbins 141 wound. As can be seen from the drawings appropriate pollination containers I42, I43 with perforated floors are provided, around the various threads before they are wound onto the individual bobbins a powder agent such as talc or soapstone.

Under certain circumstances, fragments of the aluminum foil can go through of the conveyor rollers I37 and I39 adhere to the rubber threads 8a and 8, respectively. Such fragments could be removed by letting the threads through so long a bath 150 of hydrochloric acid or sulfuric acid is moved through it until the individual Foil parts are decomposed. Then the threads are in a bath 151 made of ammonium hydroxide or the like to immerse in this way the after leaving the bath I50 to neutralize acid adhering to the threads. After their neutralization are to dry the threads, to dust them and, as described above, on bobbins to wind up.

As can be seen from the drawing, either or both can Ends of the covered tape or film strip are left uncut, in order to thereby have a sufficiently wide width on the foil strip for its comfortable handling To form an edge on which the individual rubber strips, without becoming tangled, are held in their initial mutual position to one another. To achieve Such uncut spur gears on the covered film strip is a cutting roller I2g when the spur gears of the foil strip pass between it and the support roller I29 to temporarily stand out from this. If the individual rubber threads 8a and 8i are initially fastened for their winding onto the individual bobbins, like this each thread is immediately prior to its attachment to the associated bobbin of to tear off or cut off the uncut edge part of the tape.

In this way, the individual threads can be used without the risk of tangling are kept in their proper mutual relationship to one another.

The modification of the invention shown in FIGS. 15 and 16 differs from the embodiment just described in that the rubber threads 8a and 89 all together on a single coil I45 or I46 be wound up. With such a winding up of all rubber threads one each Layer on a single spool the individual threads avoiding the danger of tangles through the uncut end edges of the rubber layer in question held in their correct mutual position to each other.

Although the foil tape according to FIGS. 15 and 16 than on both of its Areas shown covered with rubber could also be just one area be provided with such a rubber layer. All you need is that in that Container T contained bath to be kept at the correct level, so that only the lower surface of the tape comes into contact with the latex of the bath.

In the event that thicker rubber threads are to be produced than this can usually be achieved in a dipping process, so the covered Slide 8 passed through a second latex bath contained in a second container will. The provided with this additional coating film 8 is then in the treated in the manner described above.

Although in the illustrated embodiments the rubber layers vulcanized before cutting, they could also be immediately after the drying process, i.e. before vulcanization, are cut up. The carrier film or the base paper carrying the rubber layer can also be exposed first a coagulant, such as. B. acetic acid, are subjected.

PITENTAN APPROACH: I. Method of making tabular articles made of rubber milk, characterized in that a cuttable metal foil (R) passed through a latex bath, whereupon the one on one or both sides Deposited coating dried on the foil, tulkanisieft, the foil together with the latex coating thereon in the shape of the desired article, e.g. B. Threads or strands, cut and the coating is stripped from the film.

Claims (1)

2. The method according to claim I, characterized in that the end edge the metal foil and the latex uncut for ease of handling remains when the metal foil and the latex for the purpose of making threads or braids be cut up. 3. The method according to claim I or 2, characterized in that - the metal foil from a roll completely or partially immersed in a latex bath is deducted. 4. The method according to any one of the preceding claims, characterized in, that the latex deposited on the metal foil is partially in hot air or gas and is partially vulcanized in water. 5. The method according to any one of the preceding claims for production of cut rubber threads, characterized in that the elasticity of the The latex is temporarily reduced, for example by quenching, before it is cut will. 6. The method according to any one of the preceding claims, characterized in, that the latex has to be dry-cleaned after separation from the metal foil adhered particles of the metal foil is subjected. 7. The method according to any one of the preceding claims, characterized in, that the separation of the latex from the metal foil by stretching the latex without significant Stretching the metal foil is facilitated. 8. The method according to any one of the preceding claims, characterized in, that on the metal foil an acid or an alkali is applied to the later applied latex to coagulate. Referenced Documents: British Patent No. 443,809.