JPS6325037B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is solid at room temperature, butyl rubber 40 ~
79% by weight, carbonaceous filler 4-30% by weight, silica filler 4-30% by weight, non-reactive phenol condensate and/or resin 4-20% by weight, thermoplastic aliphatic hydrocarbon resin 4-20% by weight. Weight% and lubricant 0.03-4% by weight
The present invention relates to a corrosion-resistant tape comprising a support coated with an extrudable adhesive comprising: The corrosion-resistant tape of the present invention is applied to a support, such as a tape, by extruding the adhesive through a wide slit nozzle, and is particularly preferably produced by coextrusion with the support. Adhesives of great industrial importance are applied to a support, which can be a tape or any other material to which an adhesive layer is applied. Generally it is necessary to obtain a uniform layer. This is a difficult task that is influenced to a large extent by the physical state of the adhesive during application to the support. Generally speaking, solutions in solvents were believed to produce favorable physical conditions for applying a uniform, sticky layer of adhesive material on a support. The technique of applying adhesive to a substrate from a solvent solution is referred to as solution coating. Solution coating has become a highly developed method. Solution coating methods have been developed despite significant drawbacks associated with the volatile organic solvents used in this type of process. Many commonly used solvents are flammable, form explosive mixtures with air, or
or toxic to humans. After applying the adhesive layer, the solvent usually has to be removed from the layer. In high-speed, high-volume production processes, it is not possible to leave the coated support alone and wait for the solvent to evaporate. Additional costs are typically incurred to facilitate solvent removal with hot air, infrared radiation, or other accelerated evaporation methods. Economic and environmental protection needs often require recovery of solvents, and the equipment and manpower to meet these requirements imposes another cost burden on this process. Because of the aforementioned drawbacks, significant efforts have been made to find alternatives to solution coating. Research has primarily focused on two approaches: replacing the solvent with water or applying the adhesive in the molten state, generally without water or solvent. When the solvent is replaced by water, the adhesive is usually in a physical state such as a suspension, emulsion, or dispersion. These aqueous systems overcome the problems of flammability, explosion hazards and toxicity hazards. However, as with solvents, it is necessary to remove the water. Unfortunately, water evaporates more slowly than normal solvents, requiring longer, more expensive, and time-consuming drying steps. Aqueous systems furthermore have the disadvantage of a limited ability to wet the desired supports, especially synthetic resin supports, which are of most industrial importance, and to form a uniform layer. Hot melt adhesives, ie adhesives that are applied to a substrate in the molten state, do not have the hazards of solvents and the drying requirements of solvent-based and aqueous systems, unlike solutions, suspensions, emulsions or dispersions. Hot melt adhesives generally have a temperature of about 120 to 200°C, preferably about 135°C.
Applied at a temperature of ~185°C. This creates drawbacks that do not normally occur in solvent-based or aqueous systems. Prolonged heating of the adhesive material during the hot melting process can lead to decomposition of the adhesive components, clogging of application equipment, and uneconomical work interruptions. Furthermore, these rather high application temperatures tend to deform the plastic sheet normally used as a support, so that the sheet does not retain its true dimensions. Additionally, due to their thermoplastic nature, conventional hot melt adhesives are sensitive to subsequent temperature effects or stresses, which can significantly impair the performance of the adhesive. Although significant efforts have been made to perfect aqueous and hot melt application systems, methods of applying adhesives from solvent solutions have proven to have significant drawbacks. That a complete solution has not yet been found is evidenced by the fact that solvent solutions are still an important element in the adhesive application industry. Accordingly, there is a need to have improved adhesive compositions and improved methods of applying them to articles and substrates. The corrosion-resistant tape of the present invention is based on the discovery of an adhesive composition that is solid at room temperature and can be extruded in the solid state. Such adhesive compositions include (a) about 40-79% butyl rubber, (b) about 4-30% carbonaceous filler, (c)
Silica filler approx. 4-30%, (d) Zinc oxide approx. 2-8
%, (e) about 2-10% oil, (f) about 4-20% non-reactive phenol condensate, (g) about 4-20% thermoplastic aliphatic hydrocarbon resin, and (h) about 0.3 lubricant. ~4% (each percentage is by weight). The corrosion-resistant tape of the present invention can also be applied, for example, by passing it through a wide slit nozzle at room temperature or higher.
It is produced by a method in which the composition is applied in the solid state to a support by extrusion onto a previously processed thermoplastic support. It is also possible to coextrude the support and a suitably formulated adhesive at slightly elevated temperatures. For example, a modification of the conventional inflation method may be used, in which the support and the adhesive used in the present invention are extruded through a two-layer wide slit nozzle, or, preferably, the adhesive is simultaneously extruded into the interior of the tubular film through a two-layer annular nozzle. can be used. Other aspects of the invention include advantageous embodiments of the invention detailed below. The adhesive composition used in the present invention is in a solid state. Advantageously, the adhesive composition contains almost no components that boil below 100°C at 760 mmHg;
Some ingredients may contain residuals or traces of liquids that boil below 100°C. If the composition contains more than a trace or residual amount of liquid, it is either insufficient to convert the composition into a substantially solid state, or it significantly interferes with extrusion of the composition. A variety of rubbers, fillers, oils, phenolic condensates or resins, aliphatic hydrocarbon resins, and lubricants may be used in the practice of this invention. Thus, for example, the availability of different rubber materials makes it possible to adapt the properties of the adhesive used in the invention to the particular application and/or support material. Similarly, various carbon fillers, silica fillers, zinc oxide fillers, oils,
The availability of phenolic resins, aliphatic hydrocarbon resins, and lubricants allows a variety of choices to be made to tailor or adapt compositions to specific applications. However, particularly advantageous results are obtained with the following advantageous components. (a) Rubber component The rubber compounded in the adhesive used in the present invention is butyl rubber, and particularly advantageous butyl rubber is about
It is a copolymer of 95-98% by weight of isobutylene and 2-5% by weight of isoprene with a degree of unsaturation of 1.5-2.0% by mole. Non-rubber materials included in the rubber mixture include:
polyterpene resins (such as those sold under the trademark "Piccolyte"), coumaron-indene resins (sold as "Neville" resin), modified rosins, rosin esters,
These include pentaerythritol esters, ester rubbers (eg, commercially available as "Vinsol" resin), and the like. Adhesive resins of this type are well known to those skilled in the art of pressure sensitive adhesives. These, in accordance with recognized principles, generally have an affinity for the support, with a view to obtaining a homogeneous blend which has dry tack to the material to which the support is to be bonded by means of an adhesive. Mixed with rubber. Rubbers, including blends of rubbers and rubbery mixtures of rubber and non-rubber materials, are tacky, unvulcanized solid rubbers that are activated by curing agents during or after application of the adhesive layer to the substrate. Or a vulcanizing agent may be present. Advantageously, the rubber itself has a Mooney viscosity of about 50 to about 80 at +100°C. Although the composition may contain any amount of rubber in the range of about 40-79%, when using the preferred butyl rubber copolymers described above, the optimum percentage of rubber is
It is 57.48%. (b) Carbonaceous Filler Component A preferred carbonaceous filler is carbon black, which may be an acetylene black, channel black, thermal black or furnace black having a surface area of about 30 to 150 ^{m 2} /g. Generally, commercially available carbon blacks have small particle sizes that are well suited for the practice of this invention. However, if the carbon black is supplied in the form of pellets which do not readily redisintegrate when mixed with rubber, for example in a Banbury mixer, it is necessary to crush the pellets before mixing them with the rubber. Particular preference is given to using activated acetylene or furnace carbon blacks. Although any amount of carbon black may be used ranging from about 4 to 30%, the optimum amount is 9.345% when using the preferred carbon black. (c) Silica Filler Component Silica may be naturally occurring or synthetic in the form of a fine powder with a surface area in the range of about 20 to 200 m ² /g. It has a molecular composition corresponding to the formula _SiO2 , and whether _SiO2 is present alone or in a mixture with other materials that does not significantly impair its functionality or the performance of the adhesive composition, The composition contains approximately equal substances. However, preference is given to amorphous synthetic silica powders or precipitates produced by precipitation or pyrogenic methods. For example, such powders are produced by evaporating silicon oxide at 2000°C or reducing dioxide at 1700°C to produce silicon monoxide. This silicon monoxide is oxidized in situ using a conventional method to obtain fine amorphous silica. In another known method, silicon tetrachloride is combusted in hydrogen and the finely divided product is collected on a cold surface. More than 99% of the products produced are
It is characterized by an extremely fine grain size that passes through 325 mesh nodes. Particular preference is given to using activated silica.
Any amount of silica can be used ranging from about 4 to 30%, but if activated silica is used, the optimum amount is
It is 9.345%. (d) Zinc oxide component Very fine zinc oxide is advantageous. More than 99% should pass through a 10000 mesh/ ^cm2 sieve.
It is particularly advantageous to use activated zinc oxide having an average particle size of about 25 to 100 microns, especially about 50 microns. Any amount of zinc oxide in the range of about 2-8% may be used, but when using the preferred active zinc oxide, the optimum amount is about 3.738%. (e) Oil Component The oil may be any light oil, natural or synthetic, having a viscosity of about 70 to 90 centistokes at +20°C. Light paraffinic mineral oils with a content of aromatics not exceeding about 10% are particularly advantageous. (f) Phenolic condensation component The phenolic condensation component used in the present invention is 1
It is a condensation product of substituted or unsubstituted phenolic compounds, including monohydric or polyhydric phenols, and aldehyde compounds reactive with the phenolic compounds, including formaldehyde, other aldehydes, and aldehyde donors or precursors. It can be prepared from any phenolic compound and any aldehyde compound or any mixture of such compounds, with or without another modifier, as long as the criteria described below are met. The phenol-aldehyde condensate should be in the form of a viscous liquid condensate or a resinous solid having a softening point of up to about 120 DEG C. by the ball and ring process. This material should be non-reactive. That is, it does not substantially react with other components of the composition under the conditions of manufacturing the adhesive composition and the conditions of application to the support. Generally, any degree of reaction that significantly impairs the extrudability or adhesion of the composition is considered substantial.
The resin used is therefore of the thermoplastic type. For this reason, the condensate or resin has a methylol content of not more than about 1%, for example about 0.3-1%. This type of condensate has no latent thermosetting properties. Unmodified and modified phenol-aldehyde condensates are known which can improve the tack retention, reduce the apparent viscosity or increase the adhesion and cohesive properties of adhesives. Generally these are oil-soluble thermoplastic phenolic resins. Known modified phenolic resins conventionally used for this type of purpose include, for example, phenol-modified coumaron indene resins, furfural-phenolic resins and terpene-modified phenolic resins, such as acidic condensation of phenols with terpene hydrocarbons or alcohols, followed by It is produced by catalytically converting a substituted phenol into a resin with formaldehyde. All phenol-aldehyde components may be viscous liquid condensates or resinous solids or materials of intermediate consistency, such as those referred to as semi-solids.
Mixtures of the aforementioned can be used. However, the most advantageous substance is an oil-soluble condensate of phenol and formaldehyde, which is solid at room temperature (20 °C), has a softening point of about 80-120 °C, about 0.3
It is a thermoplastic resin-like material with a methylol content of ~1.0%. The composition may contain any amount of phenol-aldehyde condensate or mixture of condensates ranging from about 4 to 20%, but when using the preferred phenol-aldehyde resins described above, the optimum amount is 9.813%. %
It is. (g) Thermoplastic aliphatic hydrocarbon resin component This component is approximately +70 to ++ by the ball and ring method.
It can be any resinous, primarily aliphatic oligomer or polymer with a softening point of 110°C. This generally involves the homopolymerization or copolymerization of unsaturated hydrocarbons having, for example, about 2 to 8 carbon atoms (including mixtures of unsaturated hydrocarbons having an average number of carbon atoms per molecule in this range). It is produced by a known contact method. The most preferred resins are aliphatic hydrocarbon resins consisting of one or more polymerized olefins, primarily (more than 50%) C ₅ olefins alone or in mixtures with other olefins that can be polymerized therewith, and having a molecular weight of about 1500. It is. Any amount of thermoplastic aliphatic hydrocarbon resin can be used ranging from about 4 to 20%. but,
When using advantageous resins containing mainly C ₅ olefins and having a molecular weight of about 1500, the optimal amount is
It is considered to be 7.009%. (h) Lubricant Component The lubricant can be any lubricant that is compatible with the remaining components of the mixture. With respect to this material, "lubricant" herein indicates that it is preferable to use a material that can function as a lubricant when the mixture is extruded in the solid state. Known lubricants which are solid at room temperature are, for example, metal stearates, such as calcium and zinc salts; fatty acid amides and esters, such as ethylene bisstearamide; fatty acids, such as stearic acid and hydrocarbon waxes. Increasing the amount of this type of lubricant serves to reduce the melt viscosity if it is too high. Lubricants with a melting point of about 200°C are preferred, stearic acid being the best. Any amount of lubricant ranging from about 0.3 to 4% may be used, but about 0.467% is optimal when using the preferred stearic acid. The composition is a generally tacky, homogeneous mixture that flows smoothly enough to form a flat, uniform film when extruded through a wide slit nozzle. The mixture consists essentially of the above-mentioned components and may contain significant amounts of additional substances, but no additional substances should be present which would impair the above-mentioned properties of the composition. All amounts and percentages indicated herein are by weight, and weight percentages of components (a) through (h) are by weight.
Based on the total weight of (a) to (h). If additional substances are present, they may be included in the above criteria depending on whether they are present as substitutes for components (a) to (h) or in addition to components (a) to (h). However, it does not have to be included. Examples are described below in which the resulting compositions are characterized as having a melt index of about 3 to 23, moderate to excellent cohesiveness, and acceptable to excellent extrusion performance. The composition as a whole therefore has a melt index in the range of about 3 to 23, preferably about 5 to 20, particularly preferably about 10 to 20. The standard technique for measuring melt index is
Described in ASTM standard D1238-70, which measures the flow rate (melt index) with an extrusion plastometer at 190°C using a piston load of approximately 3.04 kg/cm ² (approximately 43.251 b/in ² ). It is something to do. The melt index is expressed as the number of grams extruded per minute after discarding the first two cuts taken 5 minutes after the start of extrusion and 1 minute thereafter. The compositions of the invention are prepared in any suitable mixing equipment, especially rubber kneading equipment, such as a Banbury mixer. By adding the ingredients in stages during thorough kneading at temperatures ranging from approximately 90 to 200°C.
It is particularly advantageous to mix the components. For example, most or all of the rubber and silica can be thoroughly mixed and kneaded before adding the zinc oxide.
In a preferred operation described below, at least one part of the carbonaceous filler, the phenolic condensate and the hydrocarbon resin is added before adding the zinc oxide. Advantageously, the addition of the oil is part of or follows the final addition of the phenolic condensate and/or hydrocarbon resin. Therefore, in an advantageous method, the entire amount of rubber is first introduced into a punched dispersion kneader. The dispersion kneader is first heated to a temperature of about 90-110°C. The rubber is kneaded and ground under these conditions for about 2-3 minutes. next,
Half of the silica is added at a temperature of about 130°C and the mixture is subsequently kneaded for about 3-5 minutes. At a temperature of about 130-140°C, the remaining silica is added and the mixture is subsequently mixed for about 3-5 minutes. to the mixture at about 160-170℃,
Carbon black and two types of resin (phenol)
About half of each of the formaldehyde condensate and the thermoplastic hydrocarbon resin are blended, and the mixture is then mixed for about 3 to 5 minutes. The remaining carbon black is added along with the entire amount of zinc oxide, the mixer contents are brought to a maximum temperature of about 180 DEG-200 DEG C., and the mixture is tempered at this temperature for about 5-10 minutes. The remainder of the two resins and the entire amount of mineral oil are added at about 180-200°C and the mixture is tempered for about 3-5 minutes. Cool the mixture to about 160-170°C, add stearic acid and stir for an additional 3-5 minutes. The finished adhesive or binder is removed from the equipment, placed in a suitably processable form, and allowed to cool. Because of the inherent tackiness of the adhesive or binder composition, it is recommended that it be in a specially processable form that can be advantageously handled and processed. For example, this objective is achieved by removing the binder or adhesive composition from the production vessel or kneader by a suitable conveying mechanism, such as a feed screw, and conveying it to the extruder. The extruder forms the binder into ropes or strips which, upon exiting the extruder, are surrounded by a separating layer. This layer may be a thin film of polyethylene, for example. The rope or strip with the separating layer is then wound up, for example onto a roll. Alternatively, the binder can be granulated and stored in granule form until use. The ropes, strips or granules of adhesive or binder produced by the method described above are fed to an extruder to coat or impregnate a tape or other support. By way of example, the adhesive composition can be applied by extrusion coating, for example onto a pretreated substrate, for example a thermoplastic substrate, by means of an extruder with a wide slit nozzle. A two-layer wide slit nozzle can also be used to co-extrude the thermoplastic support and adhesive composition. A particularly advantageous method is to use a two-layer annular nozzle and extrude the thermoplastic resin support through the annular nozzle by the inflation method. A nozzle of this type with two concentric orifices can extrude the thermoplastic tubular body through one orifice and the adhesive through the other orifice, thereby allowing the substrate and one surface thereof to be extruded. At the same time, an adhesive layer that adheres to the material can be formed. According to the accepted principles of coextrusion, two materials that are extruded at the same time are extruded at the same temperature range;
They are blended so that their extrusion viscosities are fairly close and they stick to each other. Therefore, when used in the coextrusion process of the present invention, the melt index of the composition is adjusted so that the melt index is in the range of about 3 to 23 at the temperature at which the coextrusion is carried out, and the adhesive is It is advantageous for the extrusion viscosity of the mixture to be fairly close to that of the melt from which the support film is extruded. These adjustments are made by respectively increasing or decreasing the molecular weight, viscosity, and relative amounts of the components according to established principles of extrusion mixture formulation. The support coated with the adhesive as the anticorrosion tape of the invention is a thin, flexible support, such as a strip of paper, cellophane, plastic, cloth, or the like. The tapes of the present invention obtained by coating these supports with adhesives can be used to seal cracks, bond plywood, seal containers such as tanks, fasten medical bandages, protect or insulate electrical wires, etc. used for purposes. A particularly advantageous application is as a corrosion protection on metal pipes for conveying gases such as oil or natural gas. The support coated with the adhesive according to the invention adheres directly to the working surface. The bonding agent of the present invention is a pressure sensitive adhesive that adheres to a wide range of materials by simply placing the adhesive on a working surface and applying pressure. The adhesive compositions used in the present invention have one or more, usually some, and advantageously all of the following advantages. The main, essential advantage of the composition is its extrudability. This depends, in part, on the type and amount of filler used. A homogeneous adhesive can be produced from the composition according to the invention. This makes it possible to produce a roll of adhesive tape that has excellent adhesive properties and is easily unwound without leaving any adhesive on the back side. The present invention has balanced stability, adhesion and processability, is highly resistant to plastic deformation stimulated by mechanical or thermal factors, and has excellent extrusion and adhesion performance. It is possible to produce a corrosion-resistant tape having the following properties. For example, in accordance with the present invention, a plasticized polymeric film, such as a vinyl chloride or vinyl chloride-vinyl acetate film, is coated thereon and is permanently balanced with the film support to provide a stable Dry tack pressure sensitive adhesive tapes can be produced that yield tape structures. Further, according to the present invention,
It has extremely low gas permeability, excellent light resistance, oxidation resistance and ozone resistance, and good permanent bending resistance.
Corrosion-resistant tapes with excellent mechanical properties, such as rebound resilience, can be produced. The adhesive composition is
When intimately and homogeneously mixed, a special structure apparently develops between the filler particles, resembling cross-linking or having network-like properties, which favors the extrusion performance. It is clear that optimum extrusion performance is obtained when using the advantageous manufacturing method described above. Next, the present invention will be explained in detail based on examples.
All "parts" in the examples represent "parts by weight" unless otherwise specified. Example 1 (Production method of adhesive) As shown in column 1 of Table 1 below, butyl rubber 40
parts, activated zinc oxide 6 parts, activated silica 13 parts, acetylene black 20 parts, mineral oil 9 parts, hydrocarbon resin 4 parts
1, 4 parts of stearic acid and 4 parts of phenolic resin, all corresponding to particularly preferred forms of these compounds as described above, are mixed by means of the preferred kneading operation described above. The resulting composition, with a melt index of about 23, exhibits above average extrusion performance, but only mild cohesive performance. Example 2 (Preparation of Adhesive) The same ingredients used in Example 1 were mixed according to the procedure of Example 1 in the proportions shown in Table 1, column 2. The resulting adhesive has a melt index of about 15, exhibits excellent extrudability, has very good molding properties and adhesion properties, and is particularly suitable for the production of adhesive tapes. Example 3 Adhesive Preparation An additional adhesive was prepared using the ingredients and procedures of Example 1 in the proportions shown in Table 1, column 3. This adhesive has a melt index of about 7 and exhibits good extrudability and good molding properties. Example 4 (Preparation of Adhesive) Using the ingredients and procedures of Example 1, using the proportions shown in Table 1, column 4, an adhesive having a melt index of about 6 and properties similar to the product of Example 3 was prepared. A composition was produced. Example 5 Adhesive Preparation Using the materials and procedures of Example 1 and the proportions shown in Table 1, column 5, an adhesive having a melt index of about 3 was prepared. It has acceptable extrudability but excellent flocculation performance.

[Table] Example 6 Method for producing corrosion-resistant tape A corrosion-resistant tape was obtained by coextruding the adhesive and polyethylene resin obtained in Example 2 using a two-layer annular nozzle by an ordinary inflation method. Similar corrosion-resistant tapes were obtained using the adhesives described in Examples 1, 3, 4, and 5. The actual adhesion etc. using the corrosion-resistant tape of the present invention will be described below. Use the adhesive obtained in Example 2 to make an adhesive tape,
A peel strength (peel resistance) test was conducted according to the method described in German Industrial Standard (DIN) 30672. Method After removing sweat compounds from the surface of the tube, the tube surface and the adjacent coating are primed with a primer consisting of the adhesive obtained in Example 2. After the specified evacuation time,
Example 2: Connect this tube to a polyethylene sheet with a thickness of 0.3 mm
With adhesive tape coated with 0.2mm of the adhesive obtained in
Wrap the tape so that the surface overlaps by 50%, and add an additional 0.5mm thickness for mechanical protection.
It was wrapped with a roll sheet and fixed with adhesive tape.
The system was subjected to temperatures up to 50° C. and adapted to the polyethylene coating. Test 1 Test of corrosion protection band and base material as supplied Tested in accordance with DIN 30672 Chapter 5, Sections 5 and 4. The results are shown in Table 2 in comparison with standard values. 2 Testing of tube coatings Tests of tube coatings are carried out in accordance with DIN 30672 Chapter 5, 5, 5, Requirement B, and the results are listed in Table 3 in comparison with the required values. Results As is clear from the results in Tables 2 and 3, it can be said that the adhesive of the present invention has strong adhesive strength that satisfies the DIN30672 standard.

【table】

【table】

[Table] *Contained in Vaseline Having fully explained the present invention and its various advantageous embodiments above, some features will be explained in more detail below. The following description generally concerns the function of each component in the adhesive mixture used in the present invention and the physical relationships between the individual components. The substrate of the entire mixture is the rubber, in particular the butyl rubber, which has an unsaturation degree of 1.5 to 2.0 mol % and a Mooney viscosity of 50 to 80 at +100 DEG C. The butyl rubber is almost non-reactive in the total mixture, due to its very low degree of unsaturation. Only rubbers that are as resistant to aging as possible should be used, such as in the case of butyl rubber. Natural rubber and other synthetic rubbers can be used, butyl rubber being preferred. Carbon black and silicon dioxide fulfill the same function in the overall mixture. Firstly, they enhance cohesiveness, and secondly, carbon black has a coloring effect. Silicon dioxide is produced by precipitation method or pyrolysis method, 20 to 200
It is active silicon dioxide which has a surface area of m ² /g and exists in an amorphous state. Carbon black is about 30
Advantageously, it is an activated acetylene carbon black or a furnace carbon black with a surface area of ˜150 m ² /g. The zinc oxide is rubber,
It is particularly useful for preventing undesirable decomposition reactions of butyl rubber. The mineral oils mentioned primarily have the function of softeners and thus at the same time increase the inherent tack and serve to increase the tackiness of the mixture. the resin,
That is, the phenol-formaldehyde condensate and the thermoplastic aliphatic hydrocarbon resin serve to create the inherent tackiness of the entire mixture. Said fatty acids, especially stearic acid, serve as a lubricant during the production and processing of the entire mixture. The following applies to each of the three types of solid fillers mentioned above; the term "active" refers to the reactivity with which the filler is capable of participating in the solid state in reactions that, in the case of the present invention, primarily increase cohesiveness. It means having the center on its surface. The surface area was determined by the "BET" method (nitrogen absorption according to the Brunnauer, Emmet and Teller method). This method is described in “Ullmanns Enzyklopadie der technischen Hemie”.
Chemie) Volume 2/1 (Urban and Schwarzenberg, Millenchen, Berlin), 1961, pages 754 et seq., especially pages 758. Zinc oxide showed sieve fineness (more than 99% by weight passed through a 10000 mesh/cm ² sieve). The sieve fineness of the other two solid fillers is not critical. This is because secondary particles, ie aggregates, are present. According to the invention, the carbon black may be used in the form of a crowbar if desired. The carbon black is hydrophobic. The other Type 2 fillers mentioned above, namely silicon dioxide and zinc oxide, are hydrophilic. The following description relates to phenol-formaldehyde condensates. This product is a so-called "novolac" type resin, i.e. a non-curing resin formed when phenol and formaldehyde are heated in a ratio of 2:1 to 1.6 in the presence of an acid (tartaric acid, hydrochloric acid, dilute sulfuric acid, acid salts). It is an alcohol-soluble and toluene-soluble phenolic resin that can be permanently melted. The Mooney viscosity was measured using a Mooney viscometer (apparatus and method described in "Ullmans Encyclopedia der Technicsien Chemie", Vol. 9,
Urban and Schwarzenberg, Milunchen, Berlin, 1957, p. 408). The Furnes carbon black was made by the Furnes method (apparatus and method described in "Ullmans Encyclopedia der Technissien Chemie", vol. 14, Urban and Schwarzenberg, Milunchen, Berlin, 1963, 799).
page). The definition of the melt index is given in "Ullmans Encyclopedia der Technicien Chemie", vol. 14 (Urban and Schwarzberg, Milunchen, Berlin), 1963, p. 156. The punched dispersion kneader for the production of adhesives operates on the Banbury mixer principle. The dispersion kneader used in the present invention is operated by compressed air and has punches that prevent the mixture material from escaping upwardly from the mixing chamber. The wings are placed on the horizontal plane. The mixing of the materials in the kneader is extremely intensive. This is because the material is consolidated between the blades and in particular between the tank wall and the blade. Having thus described the invention and various advantageous embodiments thereof, those skilled in the art may make modifications not specifically described that fall within the scope of the invention.

Claims (1)

[Scope of Claims] 1. Mainly: (a) 40-79% butyl rubber (b) 4-30% carbonaceous filler having a surface area of about 30-150 m ² /g (c) about 20-200 m ² /g Silica with a surface area of 4
~30% (d) 2-8% zinc oxide, of which 99% or more passes through nodes of 10 000 mesh/cm ² , (e) 2-10% oil having a viscosity of approximately 70-90 centistokes at 20°C (f) 4-20% (g) of a non-reactive condensate of phenolic and aldehyde compounds having the consistency of a liquid concentrate to a resinous solid at 20°C, the resinous solid having a softening point up to about 120°C. 4 to 20% of a thermoplastic aliphatic hydrocarbon resin having a softening point of about 70 to 110°C (h) 0.3 to 4.0% of a lubricant solid at 20°C, the percentage of components (a) to (h) being: 1. A corrosion-resistant tape comprising a support coated with an adhesive in an amount of % by weight based on the total amount of components (a) to (h) in the adhesive. 2. The adhesive is (a) butyl rubber consisting of a copolymer of 95 to 98% by weight of isobutylene and 2 to 5% by weight of isoprene, with a degree of unsaturation of 1.5 to 2.0 mol % and a Mooney viscosity of 50 to 80 at 100° C. 57.480 % by weight (b) Activated acetylene black or furnace black having a surface area of approximately 30 to 150 m ² /g.
9.345% by weight (c) 9.345% by weight of active silicon dioxide with a surface area of 20 to 200 m ² /g, produced by precipitation or pyrolysis; (d) 9.345% by weight of active silicon dioxide with a mean particle size of about 50 mμ and not less than 99% by weight;
3.738% by weight of active zinc oxide passing through a sieve of 10000 mesh/cm ² (e) Aromatic content up to 10% by weight and +20°C
Mineral oil with a viscosity of 70 to 90 centistokes
2.803% by weight (f) Non-reactive and non-thermally reactive phenol formaldehyde condensate with a methylol content of about 0.3-1.0% by weight or the corresponding phenolic resin with a softening point of about 80-120°C 9.813% by weight (g ) mainly contains an olefin having 5 carbon atoms,
The corrosion-resistant tape according to claim 1, which is an adhesive comprising: 7.009% by weight of a thermoplastic aliphatic hydrocarbon resin having a molecular weight of about 1500 and a softening point of 70-110°C (h) 0.467% by weight of stearic acid. 3. The corrosion-resistant tape according to claim 1, wherein the coating on the support is carried out by an inflation method in which the support and adhesive are simultaneously extruded through a two-layer annular nozzle.