摘要:
A process for preparing a polyacrylate-based shaped article, a polyacrylate being polymerized by a conventional method, wherein the polyacrylate comprises copolymerized comonomers having thermally crosslinkable groups and comonomers having attached photoinitiators, and the polyacrylate is crosslinked thermally in a first step and by irradiation with UV light in a second step.
摘要:
A process for preparing a polyacrylate-based shaped article, a polyacrylate being polymerized by a conventional method, wherein the polyacrylate comprises copolymerized comonomers having thermally crosslinkable groups and comonomers having attached photoinitiators, and the polyacrylate is crosslinked thermally in a first step and by irradiation with UV light in a second step.
摘要:
A method of producing an adhesive tape having at least one carrier layer and two outer adhesive layers, wherein the carrier layer is from 300 μm to 5000 μm thick and is composed of a photoinitiator-free homogeneously thermally crosslinked polymer based on acrylate and/or methacrylate, in which at least one trimerized isocyanate crosslinker is added in the melt to a polyacrylate copolymer having primary hydroxyl groups and based on acrylic esters and/or methacrylic ester, a layer of the polyacrylate together with the crosslinker is conveyed to a coating unit, where pressure-sensitive adhesive layers are laminated onto both sides of the not-yet fully-crosslinked polyacrylate layer, and the crosslinking of the polyacrylate leads to a homogeneously crosslinked carrier layer.
摘要:
The invention describes a double-sided, carrierless self-adhesive tape which can be used in particular for achieving very durable adhesive bonding of a variety of articles. This double-sided, carrierless self-adhesive tape is composed of a homogeneously crosslinked pressure-sensitive acrylate hotmelt composition of single-layer construction, which may have been lined with release materials such as siliconized release papers or release films. The double-sided, carrierless pressure-sensitive adhesive tape is characterized in that it is composed of a photoinitiator-free, thermally homogeneously crosslinked acrylate hotmelt which is crosslinked predominantly by way of urethane units. It is notable in particular for the fact that it is homogeneously chemically crosslinked through the layer and, in contrast to acrylate layers crosslinked by radiation (UV/EBC), does not exhibit any profile of crosslinking through the layer. It can be used in particular as an adhesive transfer tape for the permanent attachment of articles to a variety of substrates.
摘要:
A process for producing an adhesive tape with single- or double-sided crosslinked pressure-sensitive acrylate hotmelt adhesive layer, wherein a crosslinker is added in the melt to a polyacrylate copolymer (“polyacrylate”) based on acrylic and/or methacrylic esters, the polyacrylate with crosslinker is conveyed to a coating unit, where it is applied to a web-form layer and following application is homogeneously crosslinked, where the crosslinker is a thermal crosslinker and some of the acrylic and/or methacrylic esters contain primary hydroxyl groups and addition takes place preferably in an extruder.
摘要:
The invention describes a double-sided pressure-sensitive adhesive tape of the kind which can be used in particular for achieving very durable bonds at high temperatures. These adhesive tapes, especially adhesive assembly tapes for the permanent fixing of articles to substrates, are preferably of multilayer construction. The inventive double-sided pressure-sensitive adhesive tapes are characterized in that the viscoelastic carrier layer is composed of a photoinitiator-free, thermally homogeneously crosslinked acrylate hotmelt. They are further characterized in that these homogeneously thermally crosslinked acrylate hotmelts have crosslinking sites by way of urethane units. This viscoelastic carrier layer is covered on both sides in each case by adhesive layers, preferably pressure-sensitive adhesive layers. These layers are connected by chemical reaction to the viscoelastic carrier layer. The operation for producing the adhesive tapes constitutes the corona pretreatment of the adhesive layers following their coating onto release material, the two-dimensional application and shaping of the acrylate hotmelt for thermal crosslinking, a thermal crosslinker having been added to the hotmelt prior to coating, the lamination of the layers together, and the afterreaction on the product in bale form, preferably without introduction of additional heat for crosslinking. This method ensures particularly effective anchoring even of different materials, which is particularly positive for the technical adhesive properties of the adhesive assembly tape.
摘要:
A process for producing an adhesive tape with single- or double-sided crosslinked pressure-sensitive acrylate hotmelt adhesive layer, wherein a crosslinker is added in the melt to a polyacrylate copolymer (“polyacrylate”) based on acrylic and/or methacrylic esters, the polyacrylate with crosslinker is conveyed to a coating unit, where it is applied to a web-form layer and following application is homogeneously crosslinked, where the crosslinker is a thermal crosslinker and some of the acrylic and/or methacrylic esters contain primary hydroxyl groups and addition takes place preferably in an extruder.
摘要:
A pressure-sensitive adhesive comprising organic fillers, obtainable by a process in which a thermal crosslinker is added in the melt to a polyacrylate copolymer (“polyacrylate”) based on acrylic esters and/or methacrylic esters, at least a fraction of which contains primary hydroxyl groups, at least one organic filler has been or is added to the polyacrylate, the polyacrylate provided with the crosslinker and the filler is conveyed to a coating unit, where it is applied to a web-form coat of a further material and, following application, is homogeneously crosslinked, a process as outlined above, and adhesive tapes furnished with the pressure-sensitive adhesive.
摘要:
Process for UV-initiated thermal crosslinking within a hotmelt process for the preparation of polyacrylate hotmelt adhesives, in which a polymer is produced from an acrylate-based comonomer mixture that includes monomers which carry at least one functional group capable of reacting with a photochemically generated base, with or without the addition of a catalyst, and then coating this polymer onto a backing, irradiating within the coating process or thereafter, and finally subjecting the polymer to thermal treatment, with crosslinking occurring between the polymer and the photochemically generated base. Structural crosslinking of the sheetlike pressure-sensitive adhesive can be produced if irradiation takes place through a mask.
摘要:
The invention relates to an oriented pressure-sensitive adhesive and to a process for preparing it.The pressure-sensitive adhesive comprises an acrylate-based UV-crosslinked polymer which is synthesized in a mass fraction of at least 50% from at least one acrylic monomer according to the general formula (I) in which R1 is hydrogen (H) or a methyl group (CH3) and R2 is hydrogen (H) or a branched or unbranched, saturated C1 to C30 hydrocarbon radical, which may optionally be substituted by a functional group, the pressure-sensitive adhesive, in the form of a film applied as a melt (hotmelt), having a preferential direction which is characterized in the free film by a shrinkback of at least 3% relative to an original stretching of the film in the preferential direction. The orientation is generated after polymerization by means of a suitable coating process and is subsequently “frozen in” by UV crosslinking. The pressure-sensitive adhesive is outstandingly suitable for use as an adhesive layer on single-sided or double-sided adhesive tapes.