KR20070004837A - Microsphere containing electron beam cured pressure-sensitive adhesive tapes and methods of making and using same - Google Patents

Abstract

The present invention provides pressure sensitive adhesive tape including at least one electron beam cured (EB-cured), rubber-based pressure sensitive adhesive (PSA) core including microspheres. The core layer is coated on at least one side, and in one embodiment, on both sides, with a skin layer including an EB-cured rubber-based PSA that is substantially free of microspheres. The core layer may comprise a lamination seam, a second core layer or a non-woven support layer. ® KIPO & WIPO 2007

Description

MICROSPHERE CONTAINING ELECTRON BEAM CURED PRESSURE-SENSITIVE ADHESIVE TAPES AND METHODS OF MAKING AND USING SAME}

The present invention relates to microsphere-containing pressure-sensitive adhesive tapes, more particularly microsphere-containing electron beam cured rubber-based pressure-sensitive adhesive tapes and methods of making and using the same.

Various double-sided foam pressure sensitive adhesive (PSA) tapes have been used in a variety of articles for structural bonding, spot welding, tack welding and replacement of rivets and mounting of objects to substrates. Such applications include, for example, coupling of body side moldings to automobiles and other vehicles, coupling of fiberglass body panels to motorhomes, coupling of plexiglass inspection windows to appliance showcases, and the like. The foam layer of these PSA tapes typically has a polymer matrix based on polyethylene, polyurethane, polyvinyl chloride or polychloroprene. Many of these tapes exhibit poor registration around curved substrates and / or poor adhesion to surfaces such as painted or thermoplastic polyolefin (TPO) surfaces. In some cases, it is necessary to apply a primer to the surface before placing the object in order to obtain proper adhesion. In such applications, the adhesive tape is generally not intended to be removable. However, especially in applications such as automobiles or other outdoor applications, adhesive tapes may be exposed to sunlight, water, organic materials (such as gasoline) and solvents (such as alcohols) used in windshield cleaning or antifreeze. These components may undesirably cause desorption of the object mounted on the substrate or surface.

Thus, for use in such applications, there is a need for foamed PSA tapes that provide a strong, permanent and consistent adhesion of the object to the desired substrate and which can withstand the various forces and components exposed during its use.

Summary of the Invention

The present invention provides a pressure sensitive adhesive tape comprising at least one electron beam cured (EB-cured) rubber-based pressure sensitive adhesive (PSA) core comprising microspheres. The core layer is covered with at least one face, in one embodiment, with a skin layer comprising two sides of an EB-cured rubber-based PSA, which is substantially free of microspheres. The core layer may comprise a laminated seam, a second core layer or a nonwoven support layer. The invention also relates to a method of mounting an object to a substrate using a PSA tape comprising at least one EB-cured rubber-based PSA core comprising microspheres. The core layer is covered with at least one face, in one embodiment, with a skin layer comprising two sides of an EB-cured rubber-based PSA, which is substantially free of microspheres.

The pressure sensitive adhesive tape of the present invention exhibits high conformity due to the low elastic memory properties of the core layer. The tape also exhibits fracture strain, high cleavage peel and tensile adhesion and good gasoline and moisture resistance.

In one embodiment, the present invention comprises an electron beam cured (EB-cured) rubber-based PSA core comprising non-hard polymeric microspheres and having first and second major faces, and adhered to the first major faces and microscopically. A pressure-sensitive tape comprising an EB-cured rubber-based PSA sheath layer substantially free of spheres. In one embodiment, the tape further comprises an EB-cured rubber-based second PSA skin layer having a first major face and a second major face, wherein the first major face of the second EB-cured rubber-based PSA skin layer is It is bonded to the second major face of the EB-cured rubber-based PSA core. In another embodiment, the tape further comprises a second EB-cured rubber-based PSA core bonded to the second major face of the second EB-cured rubber-based PSA sheath layer and comprising non-hard polymeric microspheres, And a third EB-cured rubber-based PSA sheath layer adhered to the second core. In another aspect, the present invention further provides a PSA tape comprising a nonwoven polymeric support layer between a first major face of a second EB-cured rubber-based PSA sheath layer and a second major face of an EB-cured foamed rubber-based PSA core. It is about.

In another aspect, the invention also provides an EB-cured rubber-based PSA core comprising microspheres and having a first and a second major face; An EB-cured rubber-based PSA skin layer adhered to the first major face and substantially free of microspheres; A second EB-cured rubber-based PSA core comprising microspheres and having first and second major faces; And a second EB-cured rubber-based PSA sheath layer substantially free of microspheres and adhered to the first major face of the second EB-cured rubber-based PSA core, wherein the PSA tape comprises 2 main face is bonded to the second main face of the second core to form a laminated seam).

In yet another aspect, the present invention provides a method for producing a rubber composition comprising: a first EB-curable rubber-based PSA core comprising microspheres and having first and second major faces; A first EB-curable rubber-based PSA sheath layer adhered to the first major face of the first EB-curable rubber-based PSA core; A second EB-curable rubber-based PSA core comprising microspheres and having first and second major faces, wherein the first major face of the second EB-curable rubber-based PSA core is a second of the first EB-curable rubber-based PSA core Adhered to the main face and a laminated seam is formed between the first EB-curable rubber-based PSA core and the second EB-curable rubber-based PSA core); And a second EB-curable rubber-based PSA skin layer adhered to the first major face of the second EB-curable rubber-based PSA core, wherein both the first and second EB-curable rubber-based PSA skin layers substantially comprise microspheres. And double-sided adhesive tape).

In yet another aspect, the present invention provides a method for producing a rubber composition comprising: a first EB-curable rubber-based PSA core comprising microspheres and having first and second major faces; An EB-curable rubber-based PSA skin layer adhered to the first major face of the first EB-curable rubber-based PSA core, which is substantially free of microspheres; And a second EB-curable rubber-based PSA core having microspheres and having first and second major faces, wherein the first major face of the second EB-curable rubber-based PSA core is the first EB-curable rubber-based PSA core. Two-sided adhesive tape bonded to the two main faces and having a laminated seam formed between the first EB-curable rubber-based PSA core and the second EB-curable rubber-based PSA core.

In another aspect, the present invention relates to a method of making and using an adhesive tape. For example, in one aspect, the present invention provides an object and a substrate to which the object is to be bonded, providing an EB-curable rubber-based PSA tape, adhering the object to one side of the PSA tape and a PSA tape A method of mounting an object to a substrate, the method comprising adhering the other side of the substrate to a substrate. If desired for various applications, additional core layers or skin layers may be added to the PSA tape.

1 is a schematic cross-sectional view of an adhesive tape having a core and one skin layer according to one aspect of the invention.

2 is a schematic cross-sectional view of an adhesive tape having a core and two skin layers according to another aspect of the present invention.

3 is a schematic cross-sectional view of an adhesive tape having two core layers (one of which has one skin layer) and a nonwoven polymer support layer separating the core layers, according to another aspect of the present invention.

4 is a schematic cross-sectional view of an adhesive tape having two core layers (one of which has one skin layer) and a separator layer substantially free of microspheres according to another aspect of the present invention; .

5 is a schematic cross-sectional view of an adhesive tape having two core layers (each having a skin layer) and a separator layer substantially free of microspheres in accordance with another aspect of the present invention.

6 is a schematic cross-sectional view of an adhesive tape having a laminated seam between two core layers, two skin layers, and core layers in accordance with another aspect of the present invention.

7 is a schematic cross-sectional view of an adhesive tape having two core layers, two skin layers, and a nonwoven polymeric support layer between the core layers, according to another aspect of the present invention.

8 is a schematic cross-sectional view of an adhesive tape having a laminated seam between two core layers, one skin layer, and core layers in accordance with another aspect of the present invention.

It is to be understood that the components shown in the drawings are not necessarily drawn to scale for simplicity and clarity of illustration. Also, where considered appropriate, reference numerals are repeated among the figures to indicate corresponding components.

In addition, it should be understood that the process steps and structures described below may not form a complete process flow for producing the final PSA tape. The present invention can be practiced in combination with manufacturing and use techniques commonly used in the art, and includes as many steps as are necessary to understand the invention from among the commonly performed process steps.

As used in the specification and claims, the term “lamination shim” is defined as the junction formed when two cured pressure sensitive adhesives are laminated together.

As described above, the present invention relates to a rubber-based pressure-sensitive adhesive tape that contains microspheres and is electron beam cured. The tape includes a core layer and one or more skin layers. The tape generally has a thickness of about 5 to about 100 mils, or about 10 to about 80 mils, or about 15 to about 70 mils.

Core layer

The core layer can be monolayer or multilayer. The core comprises an electron beam cured rubber-based pressure sensitive adhesive and microspheres. The core may comprise a laminated shim, a second core layer or a nonwoven support layer. In one embodiment, the thickness of the core is about 5 to about 100 mils, or about 10 to about 80 mils, or about 15 to about 70 mils.

The pressure sensitive adhesive core includes one or more electron beam cured rubber-based adhesives and one or more microspheres. In one embodiment, the EB-cured rubber-based pressure sensitive adhesive constitutes about 35 to about 70 volume percent, or about 40 to about 65 volume percent, or about 50 to about 60 volume percent of the core layer and the remainder comprises microspheres. It consists of a filler containing. Throughout this section and the specification and claims, limitations in the scope and ratio may be combined. Thus, for example, about 30 to about 60 volume percent, although not specifically described in the above disclosure, is considered to be within the scope of the disclosure.

Rubber-based PSA polymer matrices useful in the present invention can be formulated as a solvent, hot melt or emulsion. The adhesive is in one embodiment a hot melt and in another embodiment a solvent type adhesive. In one embodiment, the PSA matrix used is based on diblock and triblock polymers and mixtures thereof. Other resin modified elastomers can be used. In one embodiment, the EB-curable rubber-based core polymer has a net effective glass transition temperature (Tg) of about 15 to about 70 ° C. below the use temperature. In another embodiment, the rubber-based core polymer has a net effective glass transition temperature (Tg) of about 30 to about 60 ° C. below the use temperature. Rubber-based materials suitable for use as electron beam cured rubber-based PSAs in the present invention are described, for example, in US Pat. No. 3,239,478 to Harlan, US Pat. No. 4,152,231 to Clair et al., Corp. US Patent No. 3,676,202 to Korpman, US Patent No. 3,783,072 to Coffman, US Patent No. 3,932,328 to Coffman, US Patent No. 4,028,292 to Coffman, Rice If described in US Pat. No. 4,820,746 to US Pat. No. 5,856,387 to Sasaki et al., All of these patents are incorporated herein by reference for teachings relating to rubber-based PSA materials.

In one embodiment, the EB-curable rubber-based core polymer is a block copolymer having or containing small amounts of tetrablock structure A-B-A-D, triblock structure A-B-A, and optionally diblock structure A-B as a minor component. In such block structures, A is non-rubber, glassy or crystalline at service temperatures, for example from about -20 to about 50 ° C. B and D, which may be identical, each represent a block that is rubbery or elastomeric at the temperature of use. At elevated temperatures, the A, B and D blocks are sufficiently fluid to coextrude the EB-curable rubber-based polymer.

In one embodiment, EB-curable rubber-based pressure sensitive adhesives useful in the present invention include styrene-butadiene-styrene, styrene-isoprene-styrene, styrene-butadiene, and styrene-isoprene block copolymers such as Shell Chemical Company. At least one of KRATON® manufactured and marketed by Chemical Company.

Block copolymers that may be used include thermoplastic block copolymers having A and B blocks that have a linear, radial or star shape and are generally formed as what is called an ABA block copolymer. In one embodiment, the A block is a monoalkenyl arene, mainly polystyrene, having a molecular weight of about 4,000 to about 50,000, and in one embodiment of about 7,000 to about 30,000. Other suitable A blocks can be formed from alpha-methyl styrene, tert-butyl styrene and other ring alkylated styrenes, and mixtures thereof. A block is about 10 to about 50%, in one embodiment about 10 to about 30%. B is an elastomeric conjugated diene (eg butadiene or isoprene) having an average molecular weight of about 5,000 to about 500,000, in one embodiment, about 50,000 to 200,000. In one embodiment, the ABA triblock and AB diblock copolymers comprise predominantly block copolymer elastomers of adhesive and the proportion of diblock copolymer is less than about 95% of the block copolymer, in one embodiment, about 85% Less than one, and in one embodiment less than about 75%. Other conventional diene elastomers may be used in small amounts, but not to the extent that will significantly affect the adhesion properties.

In one embodiment, the core is formed of selected thermoplastic elastomers. Advantageous thermoplastic elastomers herein refer to the triblock structure ABA, wherein A represents a block that is non-rubber, glassy or crystalline but fluid at high temperature or room temperature and B is rubbery or elastomeric at effective or room temperature. And all block copolymers having or containing). In addition to the ABA triblock structures, other possible structures are the radial structure (AB) _x A (where x is greater than 1), the diblock structure AB and combinations of these structures. The elastomer may comprise about 60 to 95 weight percent rubbery segments and about 5 to about 40 weight percent non-rubber segments.

In one embodiment, the cores are SBS, SIS, SI, S (IS) _x and SEBS block aerials sold by Shell Chemical Company under the trade names KRATON® D1102, D1107, D1111, D1112, D1117, D1125 and D4141 and KRATON® G1650. Thermoplastic elastomers such as coalescing and mixtures thereof. These elastomers have hardness, Shore A values of about 32 to 75 and styrene / rubber ratios of 14/86 to 29/71.

Specific examples of ABA type copolymers of styrene and isoprene are KRATON® 1107 and KRATON® 1117 (source: Shell Chemical Company). ABA type copolymers of styrene-butadiene are available from Shell Chemical Company under the trade names KRATON® 1101 and KRATON® 1102. Other commercially available copolymer adhesives include random copolymers of ethylene and vinyl acetate with a melt flow index of 2500 and a vinyl acetate content of 14% by weight (ESCORENE® MVO-2514; commercially available from Exxon Chemical); Styrene butadiene umblock synthetic rubber with a styrene content of 30% by weight (FINAPRENE® 411; commercially available from Fina Chemical Company); Random copolymers of ethylene and vinyl acetate with a melt flow index of 148 and a vinyl acetate content of 18.5% by weight (ELVAX® 420; commercially available from DuPont); And a random copolymer of ethylene and vinyl acetate (ELVAX® 40W) with a melt flow index of 57 and a vinyl acetate content of 40% by weight.

Tackifying additives useful in the present invention include rosin or rosin derivatives, polyterpenes, hydrocarbon resins and the like. Commercially available useful tackifiers include rosin esters such as those sold under FORAL 85 (Hercules, Inc.) and trade names PICCOLYTE A-115 (Hercules, Inc.) and ZONAREZ B-100 (commercially available from Arizona). Terpene resins such as those sold commercially. Other commercially available tackifiers include REGALITE R91, REGALITE R101, REGALITE RS100 and REGALITE RS 260, REGALREZ 1018, REGALREZ 3102, REGALREZ 6108 and REGALREZ 5095, ZONATAC LITE Series (e.g. ZONATAC 105 Lite), ESCOREZ 5300 Series, FORALAX and FORALAX 105 and Herculin D.

Crosslinkers can be added to the adhesive composition of the present invention. In one embodiment, the crosslinker comprises polythiol. Useful polythiols include pentaerythritol tetrathioglycolate (PETTG), dipentaerythritol tetra (3-mercaptopropionate), pentaerythritol tetra (3-mercaptopropionate) (PETMP), trimethylol Ethane trimer captopropionate (TMETMP), trimethylolpropanetrithioglycolate (TMPTG), glycol dimercaptoacetate; 2,2, dimercaptodiether, polyethyleneglycol dimercaptoacetate, polyethyleneglycol (3-mercaptopropionate), trimethyloltri (3-mercaptopropionate), trimethylolpropane tree (3-mercaptoprop Cionate) (TMPTMP) and the like. Trimethyloltri (3-mercaptopropionate) is particularly useful. The concentrated polythiol may be about 10% by weight or less, or about 0.3 to about 3% by weight, or 0.5 to about 2% by weight, based on the total weight of the rubber.

In one embodiment, in the electron beam (EB) used as an energy source to cure the rubber-based PSA, the energy level of the EB is about 1 to about 100 kiloGray (kGy), and in one embodiment, about 10 to about 50 kGy. Alternative energy sources such as ultraviolet light can be used with EB radiation. UV irradiation may require the use of photoinitiators.

As described above, the core layer also includes one or more microspheres. In general, the microspheres can be solid, hollow or porous and can be hard or non-hard. Microspheres can be made of any suitable material, including glass, ceramic, polymer, and carbon materials. The microspheres of the core layer are generally about 10 to about 300 microns in size. In one embodiment, the microspheres are present in an amount of about 30 to about 65 volume percent, or about 35 to about 60 volume percent, or about 40 to about 60 volume percent of the core layer.

Polymeric microspheres can be made of any suitable polymeric material. Mixtures of low density microspheres can be used. Polymeric microspheres can be tacky or non-tacky. In one embodiment, the polymeric material of the microspheres can be selected to crosslink with the PSA polymer matrix during EB curing.

Polymeric microspheres can be made of hard or elastomeric materials. Suitable hard polymer materials include thermosetting polymers (such as phenolic polymers) or thermoplastic polymers (such as polyvinylidene chloride acrylonitrile copolymers (PVDC copolymers)). In one embodiment, the thermoplastic polymer microspheres are grafted to the polymer matrix when crosslinked when the polymer matrix is cured using EB radiation. Properties such as tensile strength can be improved by crosslinking microspheres and grafting to the polymer matrix.

Elastomeric microspheres are described in US Pat. Nos. 3,691,140 to Silver, US Pat. Mall US et al., US Pat. No. 4,810,763. These patents are incorporated herein by reference for their teachings relating to polymeric microspheres. Injectable low density microspheres are described in US Pat. Nos. 4,735,837, 4,049,483, 4,645,783, 4,624,893, 4,636,432, 4,598,112, and Japanese Patent No. 61258854. These references are incorporated herein by reference for the disclosure of the microspheres. Incorporation of the elastomeric microspheres in the core layer improves the low temperature performance of the foam tapes of the invention, for example, at 20 to 30 ° C., especially in the cold slam test, General Motors Testing GM 9023P.

The non-rigid polymeric microspheres may be expandable microspheres such as EXPANCEL® expandable microspheres (Casco Products, a subsidiary of AKZO NOBEL, Expancel Inc., Duluth, GA, USA). EXPANCEL® microspheres are small spherical plastic particles. Another example of a suitable expandable polymeric microsphere on the market is that Pierce Stevens (Buffalo, NY) is sold under the trade names "F30D", "F80SD" and "F100D". Expandable microspheres generally consist of a polymer shell that encapsulates a gas or vaporizable liquid. When the gas inside the shell is heated or the liquid vaporizes, its pressure is increased and the thermoplastic shell is softened, dramatically increasing the volume of the microspheres. When fully inflated, the volume of the microspheres can increase by more than 40 times its initial volume. In other embodiments, other known non-hard polymeric microspheres can be used in the core. The density of such polymeric microspheres can be from about 30 to about 70 kg / m ³ (about 0.03 to about 0.07 g / cm ³ ) for the expanded microspheres. The density of such polymeric microspheres before expansion can be about 1000 to about 1300 kg / m ³ (about 1 to about 1.3 g / cm ³ ). The expansion temperature of such polymeric microspheres may be about 60 to about 200 ° C, and in one embodiment, about 80 to about 190 ° C.

In one embodiment, the microspheres are hollow. Such microspheres of a wide range of densities and breaking strengths are generally available. In some embodiments, ceramic hollow microspheres are useful because they exhibit high crush strength and tend to be cheaper than glass, polymer or carbon hollow microspheres.

Uncoated hollow phenolic microspheres are commercially available from Eastech Chemical, Philadelphia, Pennsylvania under the trade name PHENOSET. PHENOSET BJO-0840 microspheres are characterized by particle size distribution curves having an aspect at a density of 0.10 to 0.15 g / cm ³ and about 70 microns. PHENOSET BJP-0930 microspheres are characterized by a particle size distribution curve with a maximum density of 0.104 g / cm ³ and an aspect at about 90 microns.

In one embodiment, the microspheres are fully inflated. In one embodiment, the microspheres are fully inflated prior to extruding or coating the PSA tape core containing the microspheres. In one embodiment, the microspheres are expanded by a heating step of mixing the EB-curable PSA components. In one embodiment, the microspheres are expanded by a heating step of mixing while dissolving the EB-curable PSA components in a solvent. Useful solvents are discussed below. In one embodiment, the solvent comprises about 20 to about 90% of the solution in which the PSA component is dissolved. In another embodiment, the solvent comprises more than 20% and up to about 80% of the solution.

In one embodiment, the microspheres are hard and can be made, for example, of free or phenolic or styrenic polymers. In this embodiment, the microspheres are expanded prior to addition to the rubber-based polymer composition for the core.

In one embodiment, the core comprises, for example, hard microspheres made of glass or ceramic with a density of about 0.2 to about 1.0 g / cm ³ and the load of the microspheres does not exceed about 45%, which is the load This high core layer tends to exhibit reduced elongation. In embodiments using hard polymeric microspheres having a density of less than about 0.2 g / cm ³ , such as hollow phenolic microspheres, the load can be as high as about 60 volume percent. If non-hard polymeric microspheres are used, loads as high as about 60% by volume can be used.

In one embodiment, the core comprises a filler such as fumed silica. Fillers such as fumed silica reduce the elongation of the core and increase the tensile strength. Thus, the amount of fumed silica is chosen to provide the best balance of high elongation and high tensile strength. In one embodiment, the filler is present in an amount up to about 10% by weight of the core. In some embodiments, a load greater than about 10% can result in a core that is too rigid or inadequately matched in some applications. In one embodiment, the volume load is about 3 to about 5 weight percent, with a good combination of tensile strength and elongation in this range.

In some embodiments, the density is greater than about 1 g / cm ³ and the size or average diameter is less than about 10 microns, in one embodiment, from about 0.1 to about 5 microns to reduce elongation of the core layer and increase tensile strength. Another filler, such as small hard, high density solid microspheres, can be used as or as a substitute for filler such as fumed silica. In one embodiment, the small hard, high density solid microspheres can be present in an amount up to about 5% by weight. In one embodiment, the small hard high density solid microspheres are present in an amount of about 1 to about 2 weight percent.

The load of the various fillers mentioned above depends on the precise properties sought and the amount of remaining filler present in the core layer. For example, in one embodiment, relatively high loads of solid fillers, such as fumed silica or small hard high density microspheres, can be used when the load of low density microspheres is low. Similarly, low loads can be used when the amount of microspheres is high.

In other embodiments, a number of other fillers, such as calcium carbonate, kaolin, and the like, may be incorporated into the core layer as needed.

In one embodiment, the core layer does not comprise hard microspheres.

Outer layer

As described above, the core layer has one or more skin layers on its surface. The sheath layer can be monolayer or multilayer. Typically, the skin layer is one monolayer. In one embodiment, the thickness of the skin layer is about 10 to about 250 g / m ² , which corresponds to a thickness of about 10 to about 250 microns (0.25 mm) (assuming the PSA density is about 1 g / cm ³ ). The outer layer is substantially free of microspheres (eg, less than 5% or less than 1% by volume) or free of microspheres. In one embodiment, the skin layer is an unfilled layer of EB-cured rubber-based polymer. In one embodiment, the skin layer can be filled with a pigment.

The electron beam cured rubber-based polymer of the skin layer can be all of those described above for the core. The particular rubber-based polymer selected for use in the skin layer may be the same or different from the rubber-based polymer used in the core.

tape

The PSA tapes of the present invention can be made by any suitable method. For example, in one embodiment, a mixture of rubbery polymer matrix, microspheres, optional fillers and solvents may be coated on the back film to the desired thickness. Next, the solvent is dried and removed before curing. The skin layer can be coated over the dried core layer. In contrast, the skin layer may first be coated on the back film, and then the core layer may be coated over the dried skin layer.

In another embodiment, the core and skin layers can be extruded, such as sheets, and then cured the sheets. Calendering processes can also be used when laminating together the extruded various aspects of the tape.

In one embodiment, the core is prepared by first preparing an adhesive composition containing the polymer matrix, the solvent for the polymer matrix and the required filler. The composition is introduced into the extruder and moved through the extruder by a rotating screw. While in the extruder, the solvent is removed by vacuum evaporation in one or more solvent removal apparatuses. Subsequently, the solvent free composition is extruded from the extruder. As used herein, “solvent free” means that the composition contains less than about 2 volume percent solvent.

Exemplary solvents include ethyl acetate, isopropanol, ethanol, hexane, heptane and toluene. The purpose of the solvent is to reduce the viscosity of the composition so that it can be easily handled in large quantities, for example, to easily pour from one container to another. In one embodiment, the amount of solvent is an amount sufficient to reduce the viscosity to less than about 100 Pascal-seconds (Pas). For most compositions, the amount of solvent that provides about 40 to about 80% solids content is sufficient for this purpose. In one embodiment, a composition comprising greater than about 80% solids may undesirably have a high viscosity. In another embodiment, a composition comprising less than about 40% solids may contain excess solvent, ie, more than enough solvent to reduce the viscosity to an easily operable level and excess solvent removed in the process. Should be. The particular viscosity desired depends on how the composition is introduced into the extruder and the type of solvent removal system used. One solvent removal system is disclosed in US Pat. No. 5,100,728, which is incorporated herein by reference for the teachings related to solvent removal.

In another embodiment, the adhesive composition of the core and skin layer is prepared without adding a solvent. The core and skin layers are coextruded onto the carrier film or release liner.

In another embodiment where the adhesive tape comprises two skin layers, the skin layers need not be identical in composition. It may be advantageous to use different adhesive compositions because the skin layer generally does not adhere to similar materials in the applications contemplated by the present invention. However, it is often convenient to use the same adhesive for manufacture. Suitable EB-cured rubber-based pressure sensitive adhesives have been described above.

In one embodiment, the substrate or the object or both to which the EB-cured PSA tape is to be bonded comprises the surface of at least one thermoplastic material, metal, glass, thermosetting resin or paint. In one embodiment, the thermoplastic material is a thermoplastic polyolefin (TPO). In one embodiment, the surface is not primed. In one embodiment, the TPO is not primed. In one aspect, the substrate is a vehicle. In one aspect, the vehicle is a motor vehicle. In one embodiment, the object is a vehicle body side molding.

The EB-cured PSA tapes disclosed herein can be used to cover the outer surface of substrates such as automobiles, motorcycles, bicycles, ships (e.g. ships, yachts, boats, and personal vessels), aircraft, and other types of land, marine, and aviation vehicles. It is particularly useful for joining parts such as side moldings, emblems, pin-striping and other objects. The EB-cured PSA tapes disclosed herein are particularly suitable for petroleum-based materials such as gasoline, lubricants, water-based materials such as detergents, windshield washes, rain, brine and mixtures thereof, such as " Road contaminants ") are resistant to the components encountered in the use of the substrate. In addition, the EB-cured PSA tapes disclosed herein are resistant to physical forces, which have improved peel strength to prevent removal by physical forces such as impacts, jams, breaks or other forces that would otherwise cause the object to be removed from the substrate. .

1 is a schematic cross-sectional view of an adhesive tape 10 according to one aspect of the present invention. The tape 10 includes an EB-cured rubber-based PSA core 12 and an EB-cured rubber-based PSA skin layer 14. According to the invention, the core 12 comprises microspheres and the sheath layer 14 is substantially free of microspheres.

2 is a schematic cross-sectional view of an adhesive tape 20 according to another aspect of the present invention. Tape 20 comprises an EB-cured rubber-based PSA core 12 and a pair of EB-cured rubber-based PSA sheath layers 14a and 14b adhered to the first and second major faces of the core 12. Include. According to the present invention, the core 12 comprises microspheres, and the skin layers 14a and 14b are substantially free of microspheres.

3 is a schematic cross-sectional view of an adhesive tape 30 according to another aspect of the present invention. Tape 30 includes an EB-cured rubber-based PSA core 12a, an EB-cured rubber-based PSA sheath layer 14, a second EB-cured rubber-based PSA core 12b, and a first core 12a and a second. A support layer 16 between the cores 12b. According to the present invention, both the first core 12a and the second core 12b both comprise microspheres and the skin layer 14 is substantially free of microspheres. The support layer 16 may be, for example, a woven or nonwoven polymer sheet. Such support layer 16 has a thickness of about 25 to about 500 microns (about 1 to about 20 mils), in one embodiment, about 50 to about 250 microns, and in another embodiment, about 60 to about 100 microns, in one embodiment. , About 75 microns (about 3 mils). An example of a useful backing layer is a 0.3 mil nonwoven fabric under the tradename Cerex.

4 is a schematic cross-sectional view of an adhesive tape 40 according to another aspect of the present invention. Tape 40 is a first EB-cured rubber-based PSA core 12a, a pair of EB-cured rubber-based PSA sheath layers 14a, 14b bonded to the first and second major faces of the first core 12a. ) And a second EB-cured rubber-based PSA core 12b adhered to the opposite side of the sheath layer 14b. According to the present invention, both the first core 12a and the second core 12b both comprise microspheres, and the first skin layer 14a and the second skin layer 14b are substantially free of microspheres. Do not.

5 is a schematic cross-sectional view of an adhesive tape 50 according to another aspect of the present invention. Tape 50 is a first EB-cured rubber-based PSA core 12a, a pair of EB-cured rubber-based PSA sheath layers 14a, 14b adhered to the first and second major faces of the first core 12a. ), A second EB-cured rubber-based PSA core 12b adhered to the opposite side of the envelope layer 14b, and a third envelope layer 14c adhered to the second major surface of the second core 12b. It includes. According to the invention, both the first core 12a and the second core 12b both comprise microspheres, the first skin layer 14a, the second skin layer 14b and the third skin layer 14c. Each contains substantially no microspheres.

6 is a schematic cross-sectional view of an adhesive tape 60 according to another embodiment of the present invention. Tape 60 includes a first EB-cured rubber-based PSA core 12a, a first EB-cured rubber-based PSA sheath layer 14a and a second EB adhered to a first major face of the first core 12a. A hardened rubber-based PSA core 12b, the first main face of which is bonded to the second main face of the first core 12a, and a second glue of the second main face of the second core 12b 2 EB-cured rubber-based skin layer 14b. The laminated shim 18 is defined at the interface between the first core 12a and the second core 12b. According to the invention, both the first core 12a and the second core 12b both comprise microspheres, and both the first skin layer 14a and the second skin layer 14b are substantially microspheres. do not include.

7 is a schematic cross-sectional view of an adhesive tape 70 according to another aspect of the present invention. Tape 70 includes a first EB-cured rubber-based PSA core 12a, a first EB-cured rubber-based PSA sheath layer 14a and a second EB adhered to a first major face of the first core 12a. A hardened rubber-based PSA core 12b (the first major face thereof is bonded to the second major face of the first core 12a), the second bonded to the second major face of the second core 12b An EB-cured rubber-based skin layer 14b, and a support layer 16 between the first core 12a and the second core 12b. The support layer 16 is substantially the same as described above for the support layer 16 shown in FIG. 3. According to the invention, both the first core 12a and the second core 12b both comprise microspheres, and both the first skin layer 14a and the second skin layer 14b are substantially microspheres. do not include.

FIG. 8 is a schematic cross-sectional view of an adhesive tape 80 according to another aspect of the invention, similar to the adhesive tape shown in FIG. 1 except that the core includes a laminated shim. Tape 80 includes a first EB-cured rubber-based PSA core 12a, an EB-cured rubber-based PSA skin layer 14 adhered to the first major face of the first core 12a, and a second EB- A cured rubber-based PSA core 12b, the first major face of which is bonded to the second major face of the first core 12a. The laminated shim 18 is defined at the interface between the first core 12a and the second core 12b. According to the present invention, both the first core 12a and the second core 12b both comprise microspheres and the skin layer 14 is substantially free of microspheres.

The following examples relate to examples of compositions and methods for making the electron beam cured pressure sensitive adhesive tapes.

Example 1

EB-curable rubber-based PSA cores consisted of 95.8% by weight of rubber-based adhesive solution (dry weight), 0.9% by weight of trimethylolpropane tris (3-mercaptopropionate) (TMPTMP) as a crosslinking agent and (32% by volume) hollow non-hard polymer A mixture of 3.9% by weight of sex microspheres is prepared by mixing as a 50% by weight solution of solids in toluene. The mixture is stirred at 190 ° C. for approximately one and a half hours with a sigma bladder mixer. The adhesive solution is about 19.3% by weight of styrene-butadiene-styrene linear copolymer containing about 31% styrene, about 16.1% by weight styrene-butadiene copolymer, about 25.8% by weight alphapinene tackifier, about 32.3% rosin ester tackifier % By weight and about 6.4% by weight of the compatible aromatic liquid resin. Solvent is stripped by vacuum.

An EB-curable rubber-based PSA is prepared for the skin layer which is the same as the EB-curable rubber-based PSA for the core layer, except that no microspheres are added to the solution. Solvent is stripped by vacuum.

The adhesive tape is made by coextrusion of a 50 micron skin layer (film weight about 50 g / m ² ) and a 0.8 mm core over the release liner. When the adhesive tape came out of the extruder, electron beams of 275kv and 50kGR were irradiated on both sides to form a structure such as the structure shown in FIG. The second release liner is attached to the adhesive tape. (Note that in actual use, the release liner may or may not be attached at this point depending on whether the adhesive tape should be laminated to another tape or other layer.)

Example 2

90.8 wt% (dry weight) of the adhesive used in Example 1, 3.8 wt% of hollow non-hard polymeric microspheres, BJO 0930 hollow phenolic microspheres (source: Eastech Chemical, Inc., Philadelphia, PA) 1.8 An EB-curable rubber-based PSA composition was prepared substantially the same as in Example 1, including wt% and 3.6 wt% of Cab-O-Sil® fumed silica (Source: Cabot Corp., Boston, Mass.). Solvent is stripped by vacuum.

An EB-curable rubber-based PSA is prepared for the skin layer which is the same as the EB-curable rubber-based PSA for the core layer, except that no microspheres are added to the solution. Solvent is stripped by vacuum.

The adhesive tape is made by coextrusion of a 50 micron skin layer (film weight about 50 g / m ² ) and a 0.8 mm core over the release liner. As the adhesive tape emerges from the extruder, the electron beams of 275kv and 50kGR are irradiated on both sides.

Peel strength is measured after one side of the tape is laminated to 0.127 mm Mylar. The core alone proved to have a peel strength of 5300 N / m for stainless steel substrates and a peel strength of 2960 N / m for TPO substrates. The outer layer shows a peel strength of 9400 N / m for stainless steel and 3130 N / m for TPO substrates.

The sample is believed to be blended with at least about 3% TMPTMP for electron beam curing to improve high temperature performance without adversely affecting the peel strength demonstrated above.

The adhesive tapes prepared in Examples 1 and 2 correspond to the tapes shown in FIG. 1. The tape shown in FIG. 1 lacks a release liner.

Example 3

The double-sided adhesive tape as shown in FIG. 2 was prepared by using the EB-curable rubber-based PSA composition prepared in Example 2 so that a core layer and two skin layers were placed on the release liner, one skin layer on each major side of the core layer. Prepared by coextrusion. Double-sided EB-curable rubber-based PSAs irradiate electron beams of 275kv and 50kGR on both sides as the tape exits the extruder. The second release liner is attached to the adhesive tape. The tape shown in FIG. 2 lacks a release liner.

Example 4

A laminated adhesive tape as shown in FIG. 3 was produced as follows. EB-curable rubber-based PSA tapes are prepared substantially the same as described in Example 1, including extrusion and EB curing. The second major face of the core layer is left unapplied. The second core is prepared by preparing the core as described in Example 1 and extruding and EB-curing the second core. The second major face of the second core is left uncoated. Next, a 3 mil nonwoven PET support layer is provided. The laminated adhesive tape was attached to one side of the 3 mil nonwoven PET backing layer of the first core to one side of the 3 mil nonwoven PET support layer and the second uncoated main side of the second core to the other side of the support layer. It is produced by forming the laminated adhesive tape shown. The tape shown in FIG. 3 lacks a release liner.

Example 5

An adhesive tape as shown in FIG. 4 is prepared as follows. EB-curable rubber-based PSA tapes were prepared substantially the same as described in Example 1, including extrusion and EB curing, and the second major face of the core layer was left unapplied. The second EB-curable rubber-based PSA tape was prepared as described in Example 1, including extrusion and EB curing, and the skin layer was left uncoated. The uncoated skin layer of the second tape is then laminated to the uncoated core of the first tape to form a structure as shown in FIG. The tape shown in FIG. 4 lacks a release liner.

Note that the structure shown in FIG. 4 can be produced by coextrusion of all four layers. However, it is speculated that higher strength EB curing will be required to properly cure the inner layer of such coextruded material.

Example 6

The double-sided laminated adhesive tape as shown in FIG. 5 was coextruded using the EB-curable rubber-based PSA composition prepared in Example 2 so that the core layer and two skin layers were placed with one skin layer on each major side of the core layer. To make it. Double-sided EB-curable rubber-based PSAs irradiate electron beams of 275kv and 50kGr on both sides as the tape exits the extruder. One of the outer layers is left uncoated. A second adhesive tape is prepared substantially the same as described in Example 1, with the core side left unapplied. The uncoated outer layer side of the first adhesive tape is then laminated to the uncoated core side of the second adhesive tape to form the same structure as shown in FIG. The tape shown in FIG. 5 lacks a release liner.

Note that the structure shown in FIG. 5 can be produced by coextrusion of all four layers. However, in order to properly cure the inner layer of such co-extruded, it is assumed that higher strength EB curing is required.

Example 7

A double-sided laminated adhesive tape as shown in Fig. 6 was prepared as follows. Two adhesive tapes are made substantially the same as in Example 1, with the outer side adjacent to the release liner of each tape and the second major face of the cores left unapplied. The uncoated second major surfaces of the cores are then laminated together to form a structure as shown in FIG. The tape shown in FIG. 6 lacks a release liner.

Note that the structure shown in FIG. 6 can be produced by coextrusion of all four layers. However, in order to properly cure the inner layer of such co-extruded, it is assumed that higher strength EB curing is required.

Example 8

A double-sided laminated adhesive tape as shown in Fig. 7 was prepared as follows. Two adhesive tapes are prepared substantially the same as in Example 1, with the outer side adjoining the release liner for both tapes and the second major side of the cores left unapplied. Next, a 3 mil nonwoven PET support layer is provided. The double sided laminated adhesive tape is made by attaching the uncoated second major surface of the cores to each side of the 3 mil nonwoven PET support layer to form a laminated adhesive tape as shown in FIG. The tape shown in FIG. 7 lacks a release liner.

Example 9

EB-curable rubber-based PSA cores consisted of 95.8% by weight of rubber-based adhesive solution (dry weight), 0.9% by weight of trimethylolpropane tris (3-mercaptopropionate) (TMPTMP) as a crosslinking agent and (32% by volume) hollow non-hard polymer A mixture of 3.9% by weight of sex microspheres is prepared by mixing as a 50% by weight solution of solids in toluene. The components are stirred at 190 ° C. for approximately an hour and a half with a sigma blade mixer. The adhesive solution is about 19.3% by weight of styrene-butadiene-styrene linear copolymer containing about 31% styrene, about 16.1% by weight styrene-butadiene copolymer, about 25.8% by weight alphapinene tackifier, about 32.3% rosin ester tackifier % By weight and about 6.4% by weight of the compatible aromatic liquid resin. Solvent is stripped by vacuum.

An EB-curable rubber-based PSA is prepared for the skin layer which is the same as the EB-curable rubber-based PSA for the core layer, except that no microspheres are added to the solution. The solvent is stripped by vacuum.

The adhesive tape is made by coating the sheath layer with a coating weight of about 50 g / m ² on the release liner. The core is coated over the skin layer with a thickness of about 0.8 mm. When the adhesive tape exits the extruder, 275kv and 50kGr electron beams are irradiated on both sides to form a structure such as the structure shown in FIG. The release liner is attached to the exposed side of the adhesive tape. (Note that in actual use, the release liner may or may not be attached at this point depending on whether the adhesive tape should be laminated to another tape or other layer.)

Example 10

90.8 wt% (dry weight) of the adhesive used in Example 1, 3.8 wt% of hollow non-hard polymeric microspheres, BJO 0930 hollow phenolic microspheres (source: Eastech Chemical, Inc., Philadelphia, PA) 1.8 An EB-curable rubber-based PSA composition was prepared substantially the same as in Example 1, including wt% and 3.6 wt% of Cab-O-Sil® fumed silica (Source: Cabot Corp., Boston, Mass.). Solvent is stripped by vacuum.

An EB-curable rubber-based PSA is prepared for the skin layer which is the same as the EB-curable rubber-based PSA for the core layer, except that no microspheres are added to the solution. Solvent is stripped by vacuum.

The adhesive tape is made by coating a 50 micron skin layer (about 50 g / m ² ) over the release liner. A 0.8 mm core is then coated over the skin layer. The second sheath layer is coated over the core layer and the adhesive tape is irradiated with electron beams of 275 kv and 50 kGr. The release liner is attached to the exposed side of the adhesive tape.

The sample is believed to be blended with at least about 3% TMPTMP for electron beam curing to improve high temperature performance without adversely affecting the peel strength demonstrated above.

The adhesive tapes prepared in Examples 1 and 2 correspond to the tapes shown in FIG. 1. The tape shown in FIG. 1 lacks a release liner.

Example 11

A laminated adhesive tape as shown in FIG. 3 was produced as follows. EB-curable rubber-based PSA tapes were prepared substantially the same as described in Example 9, including EB curing. Prepared as described in Example 1 by coating the second core over the release liner. Next, a 3 mil nonwoven PET support layer is provided. The laminated adhesive tape adheres the first core of the first tape to one side of the 3 mil nonwoven PET support layer and the second core of the second tape to the other side of the support layer to form a laminated adhesive tape as shown in FIG. 3. It manufactures by making it. The tape shown in FIG. 3 lacks a release liner.

Example 12

An adhesive tape as shown in FIG. 4 is prepared as follows. EB-curable rubber-based PSA tapes were prepared substantially the same as described in Example 9, including EB curing. A second EB-curable rubber-based PSA tape was prepared substantially the same as described in Example 9, including EB curing. The release liner is removed from the skin layer and the exposed skin layer is laminated to the core layer of the first tape. The release liner is attached to the core layer of the second tape to facilitate handling. The tape shown in FIG. 4 lacks a release liner.

Example 13

A double-sided laminated adhesive tape as shown in Fig. 6 was prepared as follows. Two adhesive tapes were prepared substantially the same as in Example 9, and the exposed core layers of the two tapes were laminated together. The tape shown in FIG. 6 lacks a release liner.

Example 14

The laminated adhesive tape as shown in FIG. 8 is prepared by laminating a tape prepared substantially as described in Example 9 with a tape prepared by coating a core layer over a release liner. The exposed core layer of tapes are laminated together.

Note that the structure shown in FIG. 7 can be produced by coextrusion of all four layers. However, it is presumed that higher strength EB hardening is required to properly harden the inner layer of such coextruded material.

Example 15

SBS block copolymer KRAYTON® D1102 38.8 wt%, SIS block copolymer KRAYTON® D1107 9.7 wt%, rosin ester resin FORAL 85 38.8 wt%, PICCOLYTE A-115 4.8 wt%, HERCULIN D tackifier 4.8 wt%, carbon black EB-curable rubber-based PSA cores are prepared by mixing together 1% by weight and 1.9% by weight TMPTMP as tackifier. An EB-curable rubber-based PSA is prepared for the skin layer, the same as the EB-curable rubber-based PSA for the core layer, except that no microspheres are added to the composition.

The adhesive tape is made by coextrusion of a 50 micron skin layer and a 0.8 mm core layer over the release liner. The adhesive tape is irradiated with electron beams of 275kv and 50kGr on both sides as the tape exits the extruder to form the structure shown in FIG. The second release liner is attached to the adhesive tape.

The double-sided adhesive tape shown in FIG. 2 was prepared using the core and skin layers described in Example 15. Similarly, the adhesive article of FIGS. 3-8 can be prepared using the core and skin layer compositions described in Example 15.

While the present invention has been described in connection with its preferred embodiments, it should be understood that various modifications thereof will be apparent to those skilled in the art upon reading this specification. Therefore, it is to be understood that the invention disclosed herein includes modifications falling within the scope of the appended claims.

Claims (33)

An electron beam cured rubber-based pressure-sensitive adhesive core comprising non-hard polymeric microspheres and having a first major face and a second major face, and A pressure-sensitive adhesive tape comprising an electron beam cured rubber-based pressure-sensitive adhesive envelope layer adhered to the first major face, which is substantially free of microspheres. 2. The second electron beam cured rubber-based pressure-sensitive adhesive of claim 1, wherein the second electron beam-cured rubber-based pressure-sensitive adhesive has a first major surface and a second major surface and the first major surface is bonded to the second major surface of the electron beam cured rubber-based pressure sensitive adhesive core. A pressure sensitive adhesive tape further comprising a skin layer. The pressure-sensitive adhesive tape of claim 1, wherein the microspheres are fully inflated. The pressure sensitive adhesive tape of claim 3 wherein the microspheres are present in an amount of from about 30 to about 60 volume percent of the pressure sensitive adhesive core. The pressure sensitive adhesive tape of claim 1, wherein the electron beam cured rubber-based pressure sensitive adhesive has improved adhesion to the thermoplastic polyolefin surface. The pressure-sensitive adhesive tape of claim 5, wherein the thermoplastic polyolefin is not primed. 3. The pressure sensitive adhesive of claim 2, further comprising a second electron beam cured rubber-based pressure sensitive adhesive core comprising non-hard polymeric microspheres adhered to the second electron beam cured rubber-based pressure-sensitive adhesive envelope layer. tape. The pressure-sensitive adhesive tape of claim 7, further comprising a third electron beam cured rubber-based pressure-sensitive adhesive envelope layer adhered to the second core. The nonwoven polymeric support layer of claim 2, further comprising a nonwoven polymeric support layer between the first major face of the second electron beam cured rubber-based pressure sensitive adhesive sheath layer and the second major face of the electron beam cured and foamed rubber-based pressure sensitive adhesive core. Pressure-sensitive adhesive tape. The pressure-sensitive adhesive tape of claim 1, further comprising a target object having a first outer surface and a second outer surface and attached to the first outer surface of the adhesive tape. The pressure-sensitive adhesive tape of claim 10, wherein the second outer surface of the adhesive tape is bonded to the substrate. The pressure-sensitive adhesive tape of claim 1, wherein the electron beam cured rubber-based pressure-sensitive adhesive core comprises a laminated seam. Same as the pressure-sensitive adhesive tape claimed in claim 1, A second electron beam cured rubber-based pressure-sensitive adhesive core comprising a non-polymeric polymeric microsphere and having a first major face and a second major face, and A pressure-sensitive adhesive tape further comprising a second electron beam-cured rubber-based pressure-sensitive adhesive sheath layer adhered to the first major face of the second electron beam-cured rubber-based pressure-sensitive adhesive core, A pressure sensitive adhesive tape wherein the second electron beam cured rubber-based pressure sensitive adhesive envelope layer is substantially free of microspheres and the second major face of the first core is bonded to the second major face of the second core to form a laminated seam. . The pressure-sensitive adhesive tape of claim 13, wherein one of the first and second electron beam cured rubber-based pressure-sensitive adhesive envelope layers is adhered to the object. 15. The method of claim 13, wherein one of the first and second electron beam cured rubber-based pressure-sensitive adhesive jacket layers is adhered to the substrate and the other of the first and second electron beam cured rubber-based pressure-sensitive adhesive jacket layers is bonded to the substrate. Pressure-sensitive adhesive tape adhered to the mounted object. The pressure-sensitive adhesive tape of claim 15, wherein the substrate to which the tape is bonded comprises at least one surface of a thermoplastic material, metal, glass, thermosetting material, or paint. The pressure-sensitive adhesive tape of claim 15, wherein the substrate is a vehicle. The pressure-sensitive adhesive tape according to claim 15, wherein the object is a vehicle body side molding. The nonwoven polymeric support layer of claim 13, further comprising a nonwoven polymeric support layer between the second major face of the second electron beam cured rubber-based pressure-sensitive adhesive envelope layer and the second major face of the electron beam cured foamed rubber-based pressure sensitive adhesive core. Pressure-sensitive adhesive tape. A first electron beam curable rubber-based pressure sensitive adhesive core comprising microspheres and having a first major face and a second major face, A first electron beam curable rubber-based pressure-sensitive adhesive outer skin layer adhered to the first main surface of the first electron beam curable rubber-based pressure-sensitive adhesive core, A second electron beam curable rubber-based pressure-sensitive adhesive comprising microspheres and having a first main face and a second main face, the first main face being bonded to the second main face of the first electron beam curable rubber-based pressure-sensitive adhesive core Cores, wherein the laminated seam is formed between the first electron beam curable rubber-based pressure sensitive adhesive core and the second electron beam curable rubber-based pressure sensitive adhesive core; and A second electron beam curable rubber-based pressure-sensitive outer skin layer adhered to the first main surface of the second electron beam curable rubber-based pressure-sensitive adhesive core (wherein the first and second electron beam curable rubber-based pressure-sensitive adhesive outer layers are microspheres. Substantially free of pressure sensitive adhesive tape). A first electron beam curable rubber-based pressure sensitive adhesive core comprising microspheres and having a first major face and a second major face, An electron beam curable rubber-based pressure-sensitive adhesive outer skin layer adhered to the first main surface of the first electron beam curable rubber-based pressure-sensitive adhesive core and substantially free of microspheres; A second electron beam curable rubber-based pressure-sensitive adhesive core comprising microspheres and having a first main face and a second main face, the first main face being bonded to a second main face of the first electron beam curable rubber-based pressure-sensitive adhesive core Wherein the laminated seam is formed between the first electron beam curable rubber-based pressure-sensitive adhesive core and the second electron beam curable rubber-based pressure-sensitive adhesive core. Providing an electron beam curable rubber-based pressure-sensitive adhesive core comprising expanded polymeric microspheres and having a first major face and a second major face, Applying an electron beam curable rubber-based pressure-sensitive adhesive envelope layer substantially free of microspheres to the first major face; and A method for producing a pressure-sensitive adhesive tape comprising curing an electron beam curable rubber-based pressure-sensitive adhesive core and an electron beam curable rubber-based pressure-sensitive adhesive skin layer by irradiating the electron beam to the core and the skin layer. 23. The method of claim 22, further comprising applying a second electron beam curable rubber-based pressure-sensitive adhesive skin layer substantially free of microspheres to the second major face and curing the second electron beam curable rubber-based pressure-sensitive adhesive skin layer. Further comprising, Method for producing a pressure-sensitive adhesive tape. 23. The method of claim 22, wherein the expanded polymeric microspheres are non-hard. Providing a target and a substrate to which the target should be bonded, Providing a first electron beam curable rubber-based pressure-sensitive adhesive core comprising expanded polymeric microspheres and having a first major face and a second major face, Applying a first electron beam curable rubber-based pressure-sensitive adhesive envelope layer substantially free of microspheres to the first major face, Curing the first electron beam curable rubber-based pressure-sensitive adhesive core and the first electron beam curable rubber-based pressure-sensitive adhesive skin layer by irradiating the electron beam to the core and the skin layer to form a pressure-sensitive adhesive tape, Adhering the object to one side of the pressure-sensitive adhesive tape; and Adhering the other side of the pressure-sensitive adhesive tape to the substrate, wherein the object is mounted on the substrate. 27. The method of claim 25, further comprising applying a second electron beam curable rubber-based pressure-sensitive adhesive skin layer substantially free of microspheres to the second major face and curing the second electron beam curable rubber-based pressure-sensitive adhesive skin layer. Further comprising a, the method of mounting the object on the substrate. 27. The method of claim 25, further comprising: providing a second electron beam curable rubber-based pressure sensitive adhesive core comprising expanded polymeric microspheres and having a first major face and a second major face, Applying a second electron beam curable rubber-based pressure-sensitive adhesive envelope layer to the first major face of the second electron beam curable rubber-based pressure-sensitive adhesive core, Curing the second electron beam curable rubber-based pressure-sensitive adhesive core and the second electron beam curable rubber-based pressure-sensitive adhesive skin layer by irradiating the electron beam to the second core and the second skin layer, and A composite pressure-sensitive adhesive having a second core of the second electron beam curable rubber-based pressure-sensitive adhesive core attached to the second main surface of the first electron beam-curable rubber-based pressure-sensitive adhesive core, having a laminated seam between each of the second major surfaces. Further comprising forming a tape. 27. The method of claim 25, wherein the substrate to which the pressure-sensitive adhesive tape is bonded comprises at least one surface of a thermoplastic material, metal, glass, thermosetting material or paint. 29. The method of claim 28, wherein the thermoplastic material is a thermoplastic polyolefin. The method of claim 28, wherein the object is not primed with the surface. 27. The method of claim 25, wherein the substrate is a vehicle. The method of mounting a target object on a substrate according to claim 25, wherein the target object is a vehicle body side molding. Providing the object, Providing a substrate, Providing a first electron beam curable rubber-based pressure sensitive adhesive core comprising microspheres and having a first major face and a second major face, Applying a first electron beam curable rubber-based pressure-sensitive adhesive envelope layer substantially free of microspheres to the first major face, Curing the first electron beam curable rubber-based pressure-sensitive adhesive core and the first electron beam curable rubber-based pressure-sensitive adhesive skin layer by irradiating the electron beam to the core and the skin layer, Providing a second electron beam curable rubber-based pressure sensitive adhesive core comprising microspheres and having a first major face and a second major face, Applying a second electron beam curable rubber-based pressure-sensitive adhesive envelope layer substantially free of microspheres to the first major face of the second electron beam curable rubber-based pressure-sensitive adhesive core, Curing both the second electron beam curable rubber-based pressure sensitive adhesive core and the second electron beam curable rubber-based pressure sensitive adhesive skin layer by irradiating the electron beam to the second core and the second skin layer, Attaching a second major face of the second electron beam curable rubber-based pressure sensitive adhesive core to a second major face of the first electron beam curable rubber-based pressure sensitive adhesive core to form a pressure-sensitive adhesive tape having a laminated seam between each second major face. Forming step, Adhering the object to one side of the pressure-sensitive adhesive tape; and Adhering the other side of the pressure-sensitive adhesive tape to the substrate, wherein the object is mounted on the substrate.

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