DE102007061859A1 - Process for producing a reinforced adhesive tape - Google Patents

Abstract

The present invention relates to a method for producing a reinforced adhesive tape, in which a reinforcement is connected to a carrier tape and a pressure-sensitive adhesive is applied to the carrier tape, characterized in that a hardenable material in liquid or viscous form is applied to the carrier tape to form the reinforcement , as well as adhesive tapes that can be produced by this method.

Description

The The present patent application relates to a method for the production a reinforced adhesive tape, in which a reinforcement with connected to a carrier tape and the carrier tape coated on at least one side with a pressure-sensitive adhesive, as well an adhesive tape which can be produced by such a method.

Adhesive tapes with introduced reinforcements are known from the prior art. For example, describes the CH 686673 A5 an adhesive tape that has both a longitudinal and a transverse reinforcement. A disadvantage of such adhesive tapes that during manufacture can be used only on prefabricated reinforcements.

It is therefore an object of the present invention, a method for To provide the possibility opened, the reinforcement of reinforced adhesive tapes as variable as possible.

These Task is characterized by a method of the type mentioned by solved that for producing a reinforced adhesive tape the reinforcement in liquid or viscous form from a hardenable material on the carrier tape of the adhesive tape is applied. This allows the reinforcement very much variable design.

object The present invention is therefore a process for the preparation a reinforced adhesive tape, in which a reinforcement with connected to a carrier tape and the carrier tape coated on at least one side with a pressure-sensitive adhesive, thereby in that, to form the reinforcement, a hardenable Material in liquid or viscous form on the carrier tape is applied.

Of the Invention is based on the knowledge that the application of a Reinforcement in liquid, pasty or viscous Form on the one hand opens up the possibility of reinforcements of very variable geometry to apply to the carrier tape and at the same time a firm bond between carrier tape and to achieve reinforcement. At the same time, the reinforcement can be made of different ones Materials are built.

One Another object of the present invention is an adhesive tape, that can be produced by the process according to the invention is.

The produced in the process according to the invention Reinforcement is made of a hardenable material. among them For the purposes of the present invention, for example, mixtures of monomers, oligomers and / or prepolymers to understand the by means of a nozzle, by means of an applicator head or the like Devices are applied to the carrier tape and cured there. The curing process can all known in polymerization reactions Ways are done, such as evaporation of a solvent, radical or ionic polymerization, polycondensation or polyaddition. It can the curable material catalysts be added, which accelerate the curing process, For example, photoinitiators, whereby the reinforcement after the Application by means of irradiation with a suitable radiation source is hardened.

To a further variant of the invention The process is the curable material in liquid or viscous form as a melt or in a softened state on the Applied carrier tape. In addition polymer melts come in particular in question. The material of the reinforcement is in this variant of the Heated process beyond the softening point, that is, until the material is more pasty, more viscous or liquid form. Under viscous form becomes in the sense of the present invention understood that the material has a flow behavior which the application over Nozzles or the above-described application techniques allowed. This is the case, for example, with a honey-like consistency.

The Temperature in which the curable material in liquid or viscous form is applied to the carrier tape can be adjusted so that this temperature is about the softening point the material of the carrier tape corresponds, if these Temperature is sufficient, the curable material in To bring liquid, pasty or viscous form. In this case, melts when applying the reinforcement on the carrier tape the surface of the carrier tape slightly, causing after cooling and curing carrier tape and reinforcement welded together at the contact surface are. This is a particularly strong cohesion between Arming and carrier tape achieved.

A further advantage of the method according to the invention is that, by applying the reinforcement in liquid, pasty or viscous form to the carrier tape, the reinforcement may optionally flow slightly apart after application, before it has completely hardened. As a result, the contact area between the carrier tape and the reinforcement is increased in comparison to fabric-reinforced adhesive tapes, resulting in a stronger bond between the reinforcement and the carrier tape. This is also exemplary in the 3 and 4 shown.

The Material of the carrier tape may under the present Invention selected from a variety of polymeric materials become. Examples include polyolefins, such as polyethylene including HDPE, high density polyethylene, polyethylene low density, linear low density polyethylene and linear Very low density polyethylene, polypropylene and polybutylene, Polyurethanes, vinyl copolymers, such as poly (vinyl chloride) and poly (vinyl acetate), in particular plasticized poly (vinyl chloride); olefinic copolymers, such as ethylene / methacrylate copolymers, ethylene / vinyl acetate copolymers, Acrylonitrile-butadiene-styrene copolymers and ethylene-propylene copolymers; acrylic polymers and copolymers and combinations of these materials. Co-extrudates, blends and blends of plastics or plastics and elastomeric materials such as polypropylene / polyethylene, polyurethane / polyolefin, Polyurethane / polycarbonate and polyurethane / polyester can also be used.

The Thickness of the carrier tape varies according to the field of application. For manual applications, d. H. for purposes of daily use, is a thickness of the carrier tape from 10 to 250 μm, in particular from 30 to 150 μm prefers.

To Another preferred embodiment is the carrier tape designed so that there is a severing of the tape without application a tool allows. This can be done at least one longitudinal side of the adhesive tape notches provided be. These indentations are advantageously triangular or semicircular educated. To cut the tape at any To enable location, the notches are in low Spaced apart, preferably without gaps immediately adjacent.

The Material of the carrier tape may further pretreatment be subjected. For this purpose, the carrier tape one or both sides for example, a corona pretreatment, a plasma pretreatment or other pretreatment procedures. Prefers at least the side on which the reinforcement is applied is subjected to such a pretreatment.

in the It is within the scope of the process according to the invention preferred when the reinforcement in a first step on the carrier tape is applied and in a second step, the pressure-sensitive adhesive is applied. The advantage here is that by the direct Applying the reinforcement to the support between the support and reinforcing a more stable composite is formed. Furthermore, will in the subsequent coating step with pressure-sensitive adhesive coating both the carrier tape and the reinforcement with the adhesive, whereby an adhesive tape with very good adhesion properties available is. These adhesive tapes produced according to the invention For this reason, they also have advantages in terms of adhesion properties compared to conventional fabric reinforcement Adhesive tapes, as in the latter usually the scrim or tissue is placed in the pressure sensitive adhesive and therefore often not completely wetted with pressure-sensitive adhesive is.

It is also possible, the opposite of the reinforcement Side of the carrier tape to be coated with the pressure-sensitive adhesive, or both sides of the carrier tape.

The Reinforcement can in the inventive method applied in any form on the carrier tape become. The reinforcement can be straight, for example parallel to the longitudinal edges of the adhesive tape and / or vertically to this; however, it is equally possible to use reinforcements in Apply waveform on the carrier tape. At the reinforcements in waveform, reinforcements which have a helix structure or are particularly preferred Possess double helical structure, especially if this on a carrier tape be applied, which has elastic properties. By the helical reinforcement can be the extensibility of the carrier tape be limited because when stretched in the longitudinal direction, ie in the direction of the course of the helical reinforcement, the carrier tape with manual stretching usually only so far can be stretched until the helical reinforcement almost completely stretched. Upon reaching this stretch behaves the elongated helical reinforcement like a longitudinal one Reinforcement and practically prevents the further manual Elongation, or increases for further longitudinal expansion required force considerably. It is under a manual Stretching the effect of a tensile force of about 40 N to a 2.5 cm wide tape understood in the longitudinal direction.

It is also possible with the aid of the invention Procedure the carrier tape on both sides with a reinforcement equip. This is initially on a page applied a reinforcement of a curable material, the carrier tape turned by 180 ° and from the opposite Side also provided with a reinforcement produced in this way. It However, it is also possible, one of the two sides of the carrier tape in a manner known per se with a prefabricated reinforcement, like a fleece, a scrim, a net or a fabric. This can be an additional gain of Adhesive tape can be achieved.

According to a further embodiment of the method according to the invention, a further, preferred on the carrier tape or in the adhesive tape incorporated reinforcement, which may be located on the same side of the carrier tape as the applied with the method described above reinforcement. For this purpose, for example, a nonwoven, a fabric, a scrim can be introduced into the adhesive tape in a manner known per se. As a result, an additional reinforcement of the adhesive tape can be achieved.

It is also possible with the aid of the invention Procedure adhesive tapes with a longitudinal direction diagonal running, net-like or lattice-like reinforcement to provide. Such adhesive tapes can be prefabricated Producing grid reinforcements only in a very costly way, because the common grid-shaped reinforcements in the Usually on castors only with grid orientation parallel to the longitudinal direction are available. In addition, the grid shape almost by means of the method according to the invention can be varied as desired, because not available pre-assembled Grid reinforcements must be resorted to.

It is by means of the method according to the invention possible that when crossing reinforcing types such as Lattices or the like, the crossing points are interconnected. For this purpose, the method is controlled so that the crossing points arise, before the reinforcement has hardened. The not yet cured Reinforcement flows into one another at the crossing points and becomes then to a coherent composite hardened.

As well The crossing points can not be connected be in which the curing of the curable material before the crossing points are created.

For the reinforcement can in the context of the invention Method are used a material which either elastic Features taped tapes with reinforced To generate reset properties. Should with the help of inventive method elastic tapes with an increased resilience are produced, so are preferred elastic polymers as reinforcement on the carrier tape applied. In addition, especially plasticized polyvinyl chloride, Thermoplastic elastomers (TPE), ethylene-vinyl acetate or mixtures ethylene vinyl acetate with HDPE, LDPE or LLDPE or other elastomers into consideration.

As well may be a carrier tape, which is made of practically non-stretchable Materials are provided with a reinforcement to make tapes, which also have virtually no elasticity and additional mechanical reinforcements included. As materials the virtually no stretchy reinforcements come polymers, such as Polyester or polyamide, in particular nylon, perlon or aramid, Polypropylene, LD polyethylene in question.

Of the On the carrier tape arranged pressure-sensitive adhesive can each for the production of adhesive tapes be suitable pressure-sensitive adhesive, in particular, this is selected from the group consisting from acrylates, rubber, synthetic rubber, polyurethanes and silicones.

The Adhesives based on acrylates can be made from an aqueous Matrix or be coated from a solvent, it can be z. B. be copolymers of isooctyl acrylate and acrylic acid. As a synthetic rubber z. As polyisoprenes, polybutadiene, styrene-isoprene-styrene and styrene-butadiene-styrene block copolymers and other elastomers in question. The silicone-based used according to the invention Pressure sensitive adhesives include z. B. siloxanes and silanols. PSAs can be used as solids or as a solution or in Form of dispersions are present.

The Thickness of the adhesive layer can range from 5 μm to 1000 μm vary. Preferably, a layer thickness used from 20 microns to 250 microns.

Advantageous is the adhesive coating with a basis weight of 10 to 200 g / m 2, preferably from 30 to 150 g / m 2, on the carrier tape applied.

The on at least one side applied pressure-sensitive adhesive coating can be full surface. But it is also possible that only a partial coating is present. For example, the Coating with adhesive strip or punctiform be upset. This reduces the consumption of adhesive become. But it is essential that one to the reliable Fixing the tape with sufficient surface area with Pressure-sensitive adhesive is coated.

To an embodiment of the invention Method is the curable material on the carrier tape inflamed or extruded. This can be known per se Way with heated nozzles or extruders with accordingly shaped applicator head are performed.

A another embodiment of the invention Method provides that the curable material with at least one movable in relation to the carrier tape Application head or nozzle is applied. This is one Flexible design and geometry of the applied reinforcement possible.

The Nozzles or the gun can on a movable Guide be attached, which is above the carrier tape is positioned. The carrier tape can from already prefabricated rolls are unwound or large rolls, the finished adhesive tape only after completion in the usual width of for example 2.5 cm is cut.

The Carrier tape can now below the gun or the Nozzles transported longitudinally over rollers with the nozzles, or the applicator head in the transverse direction be controlled so that an order of reinforcement in the X and Y direction is possible. It is also conceivable, the carrier tape to leave stationary and the nozzles, or the Application head by means of a movable in the X and Y direction essay over to move the carrier tape.

It is also provided, several guns or nozzles independently movable or stationary use and movable guns or nozzles simultaneously use. Which can be used to over individual nozzles or guns one longitudinally in the tape direction Apply running reinforcement and at the same time with a second Group of nozzles or applicators a transversely Apply this running reinforcement.

Of the Application head can have several openings to order the curable Reinforcing exhibit. These openings can be the same or differently shaped openings and / or diameters exhibit. The application head can be designed to be heatable.

It It is also envisaged that several nozzles will be used which are also differently shaped openings or diameter.

The Reinforcement can in the inventive method basically applied with any cross section become. The reinforcement can do this via a nozzle or applicator head with, for example, square, rectangular, triangular, oval or circular cross-section on the carrier tape be applied. It can also different Nozzles are used, creating a carrier tape is obtained, which is different sized or different having shaped reinforcements.

The Reinforcement indicates the desired application conditions adapted filament thickness. As filaments are used in the sense of present invention, the individual strands of reinforcement referred to via nozzles, applicator head or the like be applied to the carrier tape. This will be the filament thickness depending on the tensile strength of the hardenable Material and the required load capacity of provided with this reinforcement Adhesive tape selected. Typical filament diameters are between 30 and 500 μm, preferably between 50 and 300 μm, more preferably 100 to 200 microns.

A further variant of the method according to the invention provides that the carrier tape used in the process and the curable material has similar properties especially with regard to their elasticity. This can be done by choosing the materials of Carrier tape and curable material on the same or similar polymers is used. For this For example, in the use of polymer blends in each case a matching component be provided. Thus, when using a carrier tape of ethylene vinyl acetate a reinforcement can be applied, consisting of a mixture of ethylene vinyl acetate and HDPE exists.

To The process of the invention, the reinforcement be applied in the form of filaments on the carrier tape. These filaments can have different diameters or Have cross-sectional areas. It is also possible to reinforce a carrier tape with a reinforcement, in which the reinforcement consists of filaments made of different Material are constructed.

The Carrier tape can also be reinforced with a longitudinal reinforcement and provided in the transverse direction, in which, for example, the Filaments in the longitudinal direction of an elastic behavior of the reinforced carrier tape cause, whereas the filaments show in the transverse direction almost inelastic behavior and the carrier tape Consequently, it is practically not stretchable in the transverse direction. With help of the method according to the invention can so tapes with anisotropic mechanical properties be made in a relatively simple manner.

A another embodiment of the invention Procedure provides that before coating the already with the reinforcement provided carrier tape on the reinforcement facing side of the carrier tape a film substantially is applied over the entire surface. In this way it is possible Reinforced tapes produce an internal one Reinforcing exhibit. The glue is then added either applied on one of the two sides or on both sides.

One Another object of the present invention is an adhesive tape, that can be produced by the process according to the invention is.

Brief Description:

Preferred embodiments of the present invention will now be described with reference to FIGS 1 to 7 described in detail. It shows the

1 a section of an adhesive tape in plan view, in which by means of the method according to the invention filaments in the form of a helical reinforcement 2 in the x-direction on the carrier tape 1 is applied.

The 2 describes an alternative embodiment with x-directional filaments 3 and these crossing sinusoidal filaments in the transverse direction 4 , The filaments are fused together at their crossing points.

The 3 provides a method according to the invention with a reinforcement 2 equipped carrier tape 1 in cross section; For reasons of simplification, the adhesive layer was applied to that of the reinforcement 2 facing side of the carrier tape 1 is not shown. The reinforcement 2 is in this embodiment of a viscous melt through a nozzle with a round cross-section on the carrier tape 1 applied. Upon contact of the not yet cured filaments of the reinforcement 2 with the surface of the carrier tape 1 occurs in this embodiment, a slight deformation of the circular cross-section of the filaments, since the material of the filaments is still in the viscous state at this moment. This creates an enlarged contact surface between the reinforcement 2 and the carrier tape 1 , resulting in improved adhesion properties of the reinforcement 2 on the carrier tape 1 leads.

4 represents another method according to the invention with a reinforcement 2 equipped carrier tape 1 in cross section; For reasons of simplification, the adhesive layer was applied to that of the reinforcement 2 facing side of the carrier tape 1 is not shown. In this case, a carrier tape 1 with a reinforcement 2 provided, which via round nozzles as a melt in liquid form on the carrier tape 1 was applied. Due to the low viscosity of the molten material of the reinforcement 2 at the time of contact with the carrier tape 1 it comes at the interface between the filaments of the reinforcement 2 and the surface of the carrier tape 1 to a deformation of the filaments with originally circular cross-section. These flow at the contact surface to the carrier tape 1 apart, which forms a shoulder in the region of the transition to the original round cross-section. Furthermore, the circular cross section flattens before hardening of the filaments, whereby the mushroom-shaped cross-section of the filaments of the reinforcement 2 arises. So produced tapes are characterized by a good cohesion between reinforcement and carrier tape.

5 shows an inventively prepared adhesive tape in plan view with a square grid-shaped reinforcement. The angle of orientation α of the reinforcement with respect to the longitudinal direction of the carrier tape is in this case 45 °.

6 shows a further inventively prepared adhesive tape in plan view with a square grid-shaped reinforcement. The angle of orientation α of the reinforcement with respect to the longitudinal direction of the carrier strip is in this case significantly less than 45 °.

7 shows a further inventively prepared adhesive tape in plan view with a rectangular grid-shaped reinforcement. The side lengths of a single grid element a and b are different in size in this case.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - CH 686673 A5 [0002]

Claims (14)

A method for producing a reinforced adhesive tape, in which a reinforcement is connected to a carrier tape and the carrier tape is coated at least on one side with a pressure-sensitive adhesive, characterized in that for forming the reinforcement, a curable material in liquid or viscous form is applied to the carrier tape. Method according to claim 1, characterized in that that the curable material on the carrier tape is inflated or extruded. Method according to claim 1 or 2, characterized that the curable material with at least one in relation to the carrier tape movable applicator or nozzle is applied. Method according to one of the preceding claims, characterized in that a carrier tape and a curable Material that has similar properties, in particular, have a similar elasticity. Method according to one of the preceding claims, characterized in that the reinforcement via a nozzle is applied with a nearly circular cross-section. Method according to one of the preceding claims, characterized in that the reinforcement in the form of filaments is applied. Method according to Claim 6, characterized that at least partially filaments with different diameters be brought to the carrier tape. Method according to one of claims 6 or 7, characterized in that at least partially filaments made of different materials on the carrier tape become. Method according to one of claims 6 to 8, characterized in that the filaments in the longitudinal direction and / or applied in the transverse direction of the carrier tape. Method according to one of claims 6 to 9, characterized in that the filaments on the carrier tape be applied in waveform. Method according to one of the preceding claims, characterized in that the carrier tape before application the reinforcement is subjected to a corona or plasma treatment. Method according to one of the preceding claims, characterized in that on the armor facing side the carrier tape a film substantially full surface is applied. Method according to one of the preceding claims, characterized in that the pressure-sensitive adhesive on the armor facing side of the carrier tape is applied. Adhesive tape, manufacturable by a method of Claims 1 to 13.