Classifications

• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K3/00—Materials not provided for elsewhere
  • C09K3/10—Materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K3/1006—Materials in mouldable or extrudable form for sealing or packing joints or covers characterised by the chemical nature of one of its constituents
  • C09K3/1021—Polyurethanes or derivatives thereof
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/30—Low-molecular-weight compounds
  • C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
  • C08G18/3225—Polyamines
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/30—Low-molecular-weight compounds
  • C08G18/32—Polyhydroxy compounds; Polyamines; Hydroxyamines
  • C08G18/3225—Polyamines
  • C08G18/3234—Polyamines cycloaliphatic
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/30—Low-molecular-weight compounds
  • C08G18/38—Low-molecular-weight compounds having heteroatoms other than oxygen
  • C08G18/3819—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen
  • C08G18/3823—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen containing -N-C=O groups
  • C08G18/3825—Low-molecular-weight compounds having heteroatoms other than oxygen having nitrogen containing -N-C=O groups containing amide groups
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G18/00—Polymeric products of isocyanates or isothiocyanates
  • C08G18/06—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen
  • C08G18/28—Polymeric products of isocyanates or isothiocyanates with compounds having active hydrogen characterised by the compounds used containing active hydrogen
  • C08G18/40—High-molecular-weight compounds
  • C08G18/60—Polyamides or polyester-amides
  • C08G18/603—Polyamides
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09J—ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES
  • C09J175/00—Adhesives based on polyureas or polyurethanes; Adhesives based on derivatives of such polymers
  • C09J175/02—Polyureas
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2190/00—Compositions for sealing or packing joints
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G2390/00—Containers
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L23/00—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
  • C08L23/02—Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
  • C08L23/18—Homopolymers or copolymers of hydrocarbons having four or more carbon atoms
  • C08L23/20—Homopolymers or copolymers of hydrocarbons having four or more carbon atoms having four to nine carbon atoms
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
  • C08L2666/00—Composition of polymers characterized by a further compound in the blend, being organic macromolecular compounds, natural resins, waxes or and bituminous materials, non-macromolecular organic substances, inorganic substances or characterized by their function in the composition
  • C08L2666/02—Organic macromolecular compounds, natural resins, waxes or and bituminous materials
  • C08L2666/26—Natural polymers, natural resins or derivatives thereof according to C08L1/00 - C08L5/00, C08L89/00, C08L93/00, C08L97/00 or C08L99/00
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K2200/02—Inorganic compounds
  • C09K2200/0217—Salts
  • C09K2200/023—Sulfur-containing compounds
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K2200/02—Inorganic compounds
  • C09K2200/0239—Oxides, hydroxides, carbonates
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
  • C09K2200/00—Chemical nature of materials in mouldable or extrudable form for sealing or packing joints or covers
  • C09K2200/02—Inorganic compounds
  • C09K2200/0243—Silica-rich compounds, e.g. silicates, cement, glass

Definitions

• the subject of the present invention is a sealing compound which comprises
• the present invention relates, furthermore, to processes for preparing the sealing compound, to processes for producing closures, especially for the pressure-tight sealing of packaging containers, using this sealing compound, and to such closures.
• Sealing compounds of the type specified at the outset are already known from EP-B-542 766. According to EP-B-542 766, these sealing compounds are employed in producing closures for food packaging containers. The use of the sealing compounds to produce pressure-tight containers, on the other hand, is not described in EP-B-542 766.
• EP-B-546 051 proposed applying, to an already applied sealing compound, an adhesive which ensures both the sealing of the containers without an additional clamping ring and the trouble-free opening of the containers.
• the present invention is based, accordingly, on the object of providing a sealing compound which allows the production of pressure-tight containers, the containers being intended to meet the corresponding standards (for example German Hazardous Goods Ordinance Rail and Hazardous Goods Ordinance Road, Appendix A5) in relation to pressure tightness without the use of an additional clamping ring and without the additional application of an adhesive to the sealing compound.
• the sealing compound should show little or no migration of the constituents of the sealing compound into the packaged product.
• the sealing compound should also meet the other requirements commonly set, for example in relation to chemical resistance and elasticity.
• the sealing compound should be able to be applied and cured on the existing plant.
• the sealing compound of the type specified at the outset which is characterized in that it comprises G) from 1 to 40% by weight of at least one adhesive, the sum of the proportions by weight of all components (A) to (G) employed in the sealing compound being in each case 100% by weight.
• Further subjects of the present invention are processes for preparing the sealing compound, processes for producing closures, especially for the pressure-tight sealing of packaging containers, using this sealing compound, and such closures .
• Compounds suitable as component (A) of the sealing compound are all those having on average at least two isocyanate groups per molecule.
• the isocyanates in this case can be monomers or oligomers and also prepolymers having at least 2 NCO groups per molecule.
• the prepolymers can have been prepared, for example, by the reaction of a diisocyanate with a chain extender.
• (A) are not free but are present in blocked form. It is preferred to employ blocked isocyanates which at room temperature are liquid or are present as a solution or dispersion. It must also be ensured that, in the case of food packaging, the migration rate of the structural components of the isocyanate compound, for example blocking agent, into the product is as low as possible.
• blocking agents of component (A) are, in particular, compounds unobjectionable from the standpoint of foodstuffs law, for example amino acids, cyclized amino acids and sugars, and also, for example, malonic acid and malonic esters.
• Other possible blocking agents are oximes, for example acetoxime, diethyl ketoxime, acetophenone oxime, cyclohexanone oxime, cyclopentanone oxime, formaldoxime, acetaldoxime, and also phenols and caprolactams . When these blocking agents are employed, however, it should be ensured that no problems occur as a result of migration of residues of blocking agent into the product.
• Isocyanates suitable as the isocyanate component are, in particular, all those which, in the form in which they have been fully reacted with one of the above-mentioned blocking agents, are preferably liquid and lead to systems which preferably have Shore A hardnesses (DIN 53 505) of between 20 and 80.
• the isocyanate component should not be readily volatile at room temperature.
• isocyanates examples include di- and/or trimerized 2,4- and 2,6-tolylene diisocyanate, di- and/or trimerized hexamethylene diisocyanate, alone or in a mixture with small amounts of monomeric tolylene or hexamethylene diisocyanate, respectively.
• chain-extended diisocyanates especially chainextended tolylene or hexamethylene diisocyanate.
• Chain extenders employed are diols and/or triols and/or polyols and also mixtures of diols with tri- and/or polyols. It is preferred to employ di- and/or trimerized tolylene diisocyanate or tolylene diisocyanate which has been chain-extended with a diol and/or triol .
• Component (A) is employed in the sealing compound in an amount of from 20 to 95% by weight, preferably from 25 to
• Compounds (component (B) ) suitable for crosslinking the blocked isocyanates which are employed in an amount of from 1.5 to 30% by weight, preferably from 2 to 20% by weight, based in each case on the overall weight of the sealing compound, are di- and/or polyamines, especially diamines which are liquid at room temperature, particularly preferably liquid cycloaliphatic diamines, for example 4,4- diamino-3 , 3-dimethyldicyclohexylmethane, 4 , 4-diaminodicyclo- hexylmethane, polyoxypropylenetriamine having a mean molecular weight MW of from 400 to 450, and also liquid polyaminoamides such as, for example, the commercial product "Versamid 100" from the company Schering AG, and liquid polyaminoamides prepared by condensation of di- and trimeric fatty acids with aliphatic amines, and also amines having a low melting point.
• the amino groups of the amino compounds employed are generally primary and
• the isocyanate component (A) and the amine component (B) are therefore employed in the sealing compounds according to the invention preferably in amounts such that the proportion of component (A) to component (B) is between 7 : 1 and 15 : 1, particularly preferably between 10 : 1 and 14 : 1.
• the sealing compound may also, if desired, include at least one further organic polymer, preferably at least one further plastic and/or elastic and/or reactive organic liquid and/or pulverulent polymer.
• This component (C) is employed in the sealing compound in an amount of from 0 to 50% by weight, preferably from 1 to 35% by weight, based in each case on the overall weight of the sealing compound.
• Suitable modifiers are styrene- butadiene copolymers, styrene-butadiene-styrene rubber, relatively high molecular mass polyethylene homo- and copolymers, relatively high molecular mass ethylene-vinyl acetate copolymers, relatively high molecular mass vinyl acetate-ethylene copolymers, polystyrene, polyvinyl alcohols, polyamides, acrylate polymers, nitrile rubbers, polyurethane precondensates, epoxy resins, polyesters, sugars, etc.
• the sealing compound also contains from 0 to 60% by weight, preferably from 0 to 30% by weight, based in each case on the overall weight of the sealing compound, of pigments and/or fillers, such as, for example, titanium dioxide, synthetic iron oxides, organic pigments, for example phthalocyanines, tartrazines, ultramarine blue, Pigment Yellow 83, Pigment Orange 43, Pigment Orange 5, Pigment Red 4, and also magnesium silicates and aluminum silicates, amorphous and pyrogenic silica, barium sulfate, carbon black, talc, kaolin and chalk (component (D) ) .
• pigments and/or fillers such as, for example, titanium dioxide, synthetic iron oxides, organic pigments, for example phthalocyanines, tartrazines, ultramarine blue, Pigment Yellow 83, Pigment Orange 43, Pigment Orange 5, Pigment Red 4, and also magnesium silicates and aluminum silicates, amorphous and pyrogenic silica, barium sulfate, carbon black, tal
• the sealing compound may also comprise from 0 to 50% by weight, preferably from 0 to 20% by weight, based in each case on the overall weight of the sealing compound, of one or more reactive diluents (component (E) ) .
• suitable compounds are preferably polyfunctional amines, especially cycloaliphatic diamines, for example cyclohexylpropylenediamine etc.
• polyols for example propylene glycol and diethylene glycol and also reactive oils, for example vegetable oils containing OH groups, as reactive diluents.
• they have the disadvantage of a lower reactivity in comparison with polyamines.
• the sealing compound according to the invention may also comprise from 0 to 35% by weight, preferably from 1 to 20% by weight, based on the overall weight of the sealing compound, of other auxiliaries and additives (component (F) ) .
• auxiliaries and additives component (F)
• examples thereof are, in particular, low molecular mass plasticizers, for example phthalates, citrates, sebacates, octoates and the like, and also other customarily employed auxiliaries and additives, for example silicone oils .
• compositions employed as component F are waxes and silicas for obtaining specific flow properties
• thixotropic agents and, in the case of foamed sealing compounds, blowing agents, for example azodicarboxamides or sulfohydrazides .
• the sealing compound according to the invention contains less than 1% by weight, with particular preference essentially no lubricants, since the customarily employed lubricants reduce the tack of the sealing compound.
• the sealing compound is employed primarily for use in closures for pressure-tight containers of the type specified at the outset. Alternatively, it can be employed as a foamed sealing compound.
• the foaming of the sealing compounds brings about a reduction in the Shore A hardness (measured in accordance with DIN 53 505) , an increase in the flexibility, a more favorable weight/volume ratio, and the obtention of a better sealing function as a result of better deformability.
• the tack of the sealing compound is affected only slightly, in general, by the addition of foaming agents .
• the sealing compound contains from 1 to 40% by weight, preferably from 5 to 25% by weight, based in each case on the overall weight of the sealing compound, of at least one adhesive.
• Adhesives suitable in principle for use in the sealing compound according to the invention are all adhesives, especially all adhesives which at room temperature are liquid or highly viscous.
• component (G) can also be employed in the form of a liquid or highly viscous solution or dispersion. Also suitable in principle are so-called hotmelt adhesives.
• Component (G) is generally selected such that at least some of component (G) is located on the surface of the sealing compound, after the sealing compound has been applied, and ensures heightened adhesion or adhesion promotion of the sealing compound relative to the counterpart of the closure (for example metal or further sealing compound) .
• the sealing compound according to the invention it is possible, for example, to employ adhesives based on tall resins and/or colophony resins and the like.
• the adhesives preferably employed in the sealing compound according to the invention are low molecular mass, branched or, preferably, linear or substantially linear homo- and/or copolymers of aliphatic, ethylenically unsaturated hydrocarbons having 2 to 6 C atoms, for example polybutene and/or polyisobutylene or polyisobutene and/or ethylene-propylene copolymers and/or ethylene-vinyl acetate copolymers.
• the preparation of the sealing compound takes place by mixing the individual components, with or without first adding the insoluble components, for example pigments, to component (A) and - where necessary - carrying out dispersion using the dispersing equipment customary in the coating industry. In the case of the preparation of non- foamed sealing compounds, mixing or dispersing is usually carried out under vacuum.
• the sealing compound prepared in this way generally has Shore A hardnesses (DIN 53 505) of between 20 and 80, preferably between 25 and 70.
• the sealing compound according to the invention is usually applied in a coat thickness of from 0.2 to 20 mm, preferably from 1 to 10 mm.
• the above-described sealing compound is applied to the closures, preferably by means of the known "injection process".
• the sealing compound is injected or pressed at slightly elevated temperature, usually from about 30 to 70°C, in the uncured, pastelike state, from one or more nozzles, into the closure parts, which are set in rotation using a suction cup or the like at high rotational speed. Owing to the centrifugal forces, the sealing composition is transferred in the desired contour and form. After this inflow is complete, curing of the sealing compound takes place at temperatures between 150°C and 240°C for a drying time of from 1 to 5 min
• the closure which is to be coated with the sealing compound is understood as being all parts of the packaging material which are connected to the body of the packaging.
• the sealing compounds are applied in pressure-tight containers as are employed for the transportation and the storage of liquid products, for example paints and inks, or other chemicals (for example goods subject to labeling requirements, which in some circumstances may be environmentally hazardous) .
• the sealing compound according to the invention is suitable, for example, for application in the containers described in EP- B-546 051, with sealing being ensured without an additional clamping ring and without the additional application of an adhesive .
• closures may consist of metals, such as aluminum, black plate, tinplate and various ferrous alloys, to which a passivating layer based on nickel compounds, chromium compounds and tin compounds may have been applied.
• the sealing compound can be applied to coated closures, but in particular, owing to the good adhesion to metals, can also be applied to uncoated closures.
• Suitable coating compositions are the coating materials, customary in the packaging industry, based on epoxy-phenolic resin, acrylate resin or polyester, or organosols .
• these coating materials are known (cf. e.g. H. Kittel, Lehrbuch der Lacke und Be Anlagen für Schweizer [Textbook of Paints and Coatings] , Volume IV, Lack- und Be Anlagenmannssysteme, Formultechnik [Paint and coating systems, formulation] , Verlag W.A. Colomb in der H. Heenemann GmbH, Berlin- Oberschwandorf 1976) and therefore require no more detailed description here.
• the sealing compounds of Examples 1 to 5 and of Comparison Example 1 are prepared from the components indicated in Table 1 by mixing.
• the tack (manually) and the exudation behavior (manually and visually) of these sealing compounds are assessed.
• the results of these investigations are likewise shown in Table 1.
• Table 1 Composition of the sealing compounds in parts, and properties of the sealing compounds

Applications Claiming Priority (3)

Publications (1)

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• 1996
  • 1996-12-21 DE DE19653914A patent/DE19653914A1/de not_active Ceased
• 1997
  • 1997-12-18 EP EP97953848A patent/EP0948575A1/de not_active Withdrawn
  • 1997-12-18 CA CA002274061A patent/CA2274061A1/en not_active Abandoned
  • 1997-12-18 BR BR9713759-6A patent/BR9713759A/pt not_active Application Discontinuation
  • 1997-12-18 AU AU57596/98A patent/AU5759698A/en not_active Abandoned
  • 1997-12-18 WO PCT/EP1997/007108 patent/WO1998028379A1/de active Search and Examination

Non-Patent Citations (1)

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