KR102196892B1 - Thin foam tape and method of manufacturing for the same - Google Patents

Abstract

The present specification provides a thin film foam tape and a method of manufacturing the same.

Description

Thin film foam tape and its manufacturing method {THIN FOAM TAPE AND METHOD OF MANUFACTURING FOR THE SAME}

The present specification provides a thin film foam tape and a method of manufacturing the same.

Foam tapes are widely used for bonding between parts of electronic products and for bonding interior products or automobile interior/exterior materials to kitchen furniture sinks or furniture for interior interiors. When such a foam tape is applied to electronic products, it is used as a cushioning material for protecting parts in various electronic products from impact or as a bonding material for bonding between parts.

In recent years, according to the trend of thinning of electronic devices, demand for a thin film foam tape having high elasticity and durability despite being a thin film is increasing. Furthermore, in the case of a conventional polyurethane-based foam tape, a problem of poor weatherability and a problem of poor adhesion in the case of a polyethylene-based foam tape have been found. Therefore, it is possible to supplement the shortcomings of the existing foam tape, and there is a need for research on a new material, a combination of materials, and a manufacturing method that can be manufactured thin.

Korean Patent Publication: KR 10-2016-0035704 A

The present specification is to provide a thin film foam tape and a method of manufacturing the same.

However, the problem to be solved by the present invention is not limited to the above-mentioned problems, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

An exemplary embodiment of the present invention, an acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres, and having a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less.

An exemplary embodiment of the present invention provides a method of manufacturing the thin film foam tape.

An exemplary embodiment of the present invention, an acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres; preparing a foam-forming composition comprising; A mixing step of melt-kneading the foam-forming composition through twin-screw extrusion; Coating the melt-kneaded foam-forming composition on a substrate by extrusion; And forming a thin film foam tape through electron beam crosslinking of the coated foam forming composition, wherein the thin film foam tape has a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less. to provide.

The thin film foam tape according to an exemplary embodiment of the present invention has an advantage of having high elastic restoring force and durability despite being a thin film.

The thin film foam tape according to an exemplary embodiment of the present invention has an advantage of having excellent thermal stability.

Since the thin film foam tape according to an exemplary embodiment of the present invention has a low density, it is possible to reduce weight when applied to electronic products, etc., and excellent adhesion can be realized due to the acrylic hot melt resin.

The thin film foam tape according to an exemplary embodiment of the present invention may realize excellent tensile strength and high elongation at break due to the low-density polyolefin elastomer.

1 schematically shows a method of manufacturing a thin film foam tape according to an exemplary embodiment of the present invention.

In the present specification, when a member is said to be located "on" another member, this includes not only the case where the member is in contact with the other member, but also the case where another member exists between the two members.

In the present specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components unless otherwise stated.

In the present specification, the unit "parts by weight" may mean a ratio of weight between each component.

In the present specification, "monomer" may refer to a unit for forming a polymer, and may refer to a prepolymer composed of the same repeating unit.

In the present specification, the "monomer polymerization unit" may mean a form in which the monomer forms a backbone, for example, a main chain or a side chain of the polymer through a polymerization reaction.

In the present specification, "Glass Transition Temperature (Tg)" refers to a heating rate in a temperature range of -70° C. to 150° C. using a DSC (Differential Scanning Calorimeter, Q-1000, TA Instrument) It may be a value determined as the midpoint of the DSC curve by measuring by increasing the temperature at 10°C/min.

In the present specification, the "weight average molecular weight" may be measured as a value in terms of polystyrene measured by GPC (Gel Permeation Chromatography).

In the present specification, the thickness of the member may be an average value of measurement values of 10 arbitrary points obtained by observing the cross section of the member with an electron microscope (SEM, TEM, STEM). When the thickness of the member is very thin, the photograph observed at high magnification can be enlarged and measured, and when enlarged, the central part of the interlayer interface line divided in width direction can be measured as a boundary line.

The present inventors have developed a method of manufacturing a foam tape in which an acrylic hot melt resin and a polyolefin elastomer, which are materials not used in the manufacture of existing foam tapes, are applied together because of poor compatibility, and through this, a thin film foam tape having excellent physical properties is manufactured. It was discovered that it was possible to develop the present invention.

Hereinafter, the present specification will be described in more detail.

An exemplary embodiment of the present invention, an acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres, and having a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less.

The thin film foam tape according to an exemplary embodiment of the present invention is uniformly mixed with an acrylic hot-melt resin, a low-density polyolefin elastomer, and a hollow microsphere, can exhibit a homogeneous performance, and has high tensile strength and durability despite a low density, At the same time, it has the advantage of having excellent adhesion.

According to an exemplary embodiment of the present invention, the thin film foam tape is an acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And it may be an extruded thin film foam tape manufactured by twin-screw extrusion of hollow microspheres. A specific method of manufacturing the thin film foam tape will be described later.

According to an exemplary embodiment of the present invention, the acrylic hot-melt resin may be an acrylic copolymer. Specifically, the acrylic copolymer may mean a heat melting type acrylic resin generally known in the art. Further, when the acrylic hot-melt resin is heated, it may be melted and appropriately dispersed in a composition containing the same.

According to an exemplary embodiment of the present invention, the acrylic hot-melt resin may include at least one of an alkyl group-containing (meth)acrylate monomer polymerization unit, a cycloalkyl group-containing (meth)acrylate monomer polymerization unit, and a polar functional group-containing monomer polymerization unit. have.

In the present specification, (meth)acrylate may mean acrylate or methacrylate.

In addition, the acrylic hot-melt resin may be prepared by polymerizing at least one of an alkyl group-containing (meth)acrylate monomer, a cycloalkyl group-containing (meth)acrylate monomer, and a polar functional group-containing monomer.

According to an exemplary embodiment of the present invention, the alkyl group-containing (meth)acrylate monomer may be one in which the above-described alkyl group is bonded to the (meth)acrylate monomer.

In the present specification, "alkyl group" may mean including a carbon chain structure in which an unsaturated bond does not exist in the functional group, and may mean including a straight or branched carbon chain structure having 1 to 20 carbon atoms. have.

According to an exemplary embodiment of the present invention, the alkyl group-containing (meth)acrylate monomer is methacrylate, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth) )Acrylate, n-butyl (meth)acrylate, t-butyl (meth)acrylate, sec-butyl (meth)acrylate, pentyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2- It may contain at least one of ethylbutyl (meth)acrylate, n-octyl (meth)acrylate, and isooctyl (meth)acrylate.

According to an exemplary embodiment of the present invention, the cycloalkyl group-containing (meth)acrylate monomer may be one in which the aforementioned cycloalkyl group is bonded to the (meth)acrylate monomer.

In the present specification, "cycloalkyl group" may include a carbocyclic structure in which an unsaturated bond does not exist in the functional group, and means including a monocyclic ring or a polycyclic ring having 2 to 20 carbon atoms. can do.

According to an exemplary embodiment of the present invention, the cycloalkyl group-containing (meth)acrylate monomer is cyclohexyl acrylate (CHA), cyclohexyl methacrylate (CHMA), isobornyl acrylate (IBOA), isobornyl methacrylate (IBOMA), isobornylmethyl (meth)acrylate, and 3,3,5-trimethylcyclohexylacrylate (TMCHA, 3,3,5-trimethylcyclohexylacrylate) may contain at least one of.

According to an exemplary embodiment of the present invention, the polar functional group-containing monomer may be a polar functional group-bonded monomer.

According to an exemplary embodiment of the present invention, the polar functional group-containing monomer may include at least one of a hydroxy group-containing monomer, a carboxyl group-containing monomer, and a nitrogen-containing monomer.

According to an exemplary embodiment of the present invention, the hydroxy group-containing monomer is 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 6-hydroxy It may contain at least one of hydroxyhexyl (meth)acrylate, 8-hydroxyoctyl (meth)acrylate, 2-hydroxyethylene glycol (meth)acrylate, and 2-hydroxypropylene glycol (meth)acrylate. .

According to an exemplary embodiment of the present invention, the carboxy group-containing monomer is acrylic acid, methacrylic acid, 2-carboxyethyl acrylic acid, 3-carboxypropyl acrylic acid, 2-(meth)acryloyloxy acetic acid, and 3-(meth)acrylo. It may contain at least one of monooxy propyl acid, 4-(meth)acryloyloxy butyl acid and acrylic acid duplex.

According to an exemplary embodiment of the present invention, the nitrogen-containing monomer is 2-isocyanatoethyl (meth)acrylate, 3-isocyanatopropyl (meth)acrylate, 4-isocyanatobutyl (meth) It may contain at least one of acrylate and (meth)acrylamide.

According to an exemplary embodiment of the present invention, the glass transition temperature of the acrylic hot melt resin is -90°C or more and -20°C or less, -90°C or more and -30°C or less, -80°C or more -20°C or less, or -80°C or more. It may be below -30 ℃.

According to an exemplary embodiment of the present invention, the weight average molecular weight of the acrylic hot-melt resin is 50,000 g/mol or more and 700,000 g/mol or less, 50,000 g/mol or more and 600,000 g/mol or less, 100,000 g/mol or more and 700,000 g/mol or less , Or 100,000 g/mol or more and 600,000 g/mol or less.

When the glass transition temperature and/or the weight average molecular weight of the acrylic hot melt resin is within the above range, the thin film foam tape may effectively implement adhesive strength.

According to an exemplary embodiment of the present invention, the low-density polyolefin elastomer has a density of 0.9 g/cm 3 or less, specifically 0.7 g/cm 3 It may be more than 0.9 g/cm 3, 0.7 g/cm 3 or more and 0.85 g/cm 3 or less, 0.8 g/cm 3 or more and 0.9 g/cm 3 or less, or 0.85 g/cm 3 or more and 0.9 g/cm 3 or less.

The density of the low-density polyolefin elastomer may mean the mass relative to the volume of the low-density polyolefin elastomer, and may be measured according to the ASTM D1505 standard.

When the density of the low-density polyolefin elastomer exceeds 0.9 g/cm 3, there is a problem in that the elastic force of the thin film foam tape is lowered, so that stress absorption and restoring force are lowered. In addition, when the density of the low-density polyolefin elastomer is less than the above range, the durability of the thin-film foam tape decreases, and the strength of the foam tape may be reduced.

According to an exemplary embodiment of the present invention, the glass transition temperature of the low-density polyolefin elastomer may be -30°C or less, and specifically -100°C or more -30°C or less, -100°C or more -40°C or less, -100°C or more- 50°C or less, -70°C to -30°C, -70°C to -40°C, -70°C to -50°C, -60°C to -30°C, -60°C to -40°C, or It may be -60 ℃ or more and -50 ℃ or less.

When the glass transition temperature of the low-density polyolefin elastomer is within the above range, the thin film foam tape may have adequate impact resistance and at the same time realize flexible physical properties. Furthermore, when the glass transition temperature of the low-density polyolefin elastomer is within the above range, the thin film foam tape may implement an appropriate adhesive strength.

According to an exemplary embodiment of the present invention, the low-density polyolefin elastomer may be a block copolymer that does not contain a diene structure. Through this, since the low-density polyolefin elastomer can prevent deterioration due to the diene structure at a high temperature, there is an advantage of ensuring the durability of the thin film foam tape.

The thin film foam tape according to an exemplary embodiment of the present invention has the advantage of implementing excellent adhesion by including the acrylic hot melt resin, and at the same time implementing excellent tensile strength by including a low density polyolefin elastomer.

According to an exemplary embodiment of the present invention, a weight ratio of the acrylic hot-melt resin and the low-density polyolefin elastomer may be 4:6 to 9:1. Specifically, the weight ratio of the acrylic hot-melt resin and the low-density polyolefin elastomer may be 4:6 to 9:2, or 5:5 to 9:3.

When the weight ratio of the acrylic hot-melt resin and the low-density polyolefin elastomer is within the above range, generation of gas due to deterioration during melt-kneading and extrusion can be prevented, thereby minimizing deterioration of physical properties of the thin film foam tape. Further, when the weight ratio of the acrylic hot-melt resin and the low-density polyolefin elastomer is within the above range, there is an advantage in that the adhesive force and the tensile force of the thin film foam tape can be simultaneously adjusted to an appropriate level.

According to an exemplary embodiment of the present invention, the tensile strength of the thin film foam tape may be 8 kgf/cm 2 or more. Specifically, the tensile strength of the thin film foam tape is 8 kgf/cm 2 or more and 20 kgf/cm 2 or less, 9 kgf/cm 2 or more and 20 kgf/cm 2 or less, 10 kgf/cm 2 or more and 20 kgf/cm 2 or less, or 10 kgf/cm 2 or more It may be less than 15 kgf/㎠.

According to an exemplary embodiment of the present invention, the elongation at break of the thin film foam tape may be 800% or more. Specifically, the elongation at break of the thin film foam tape may be 800% or more and 1000% or less.

According to an exemplary embodiment of the present invention, the peel force of the thin film foam tape to the glass substrate may be 8 N/2.5 cm or more and 20 N/2.5 cm or less. Specifically, the peeling force of the thin film foam tape to the glass substrate is 10 N/2.5 cm or more and 20 N/2.5 cm or less, 10 N/2.5 cm or more and 17 N/2.5 cm or less, or 12 N/2.5 cm or more and 15 N May be less than /2.5cm.

According to an exemplary embodiment of the present invention, the surface energy of the thin film foam tape may be 34 mN/m or more and 40 mN/m or less. Specifically, the surface energy of the thin film foam tape may be 34 mN/m or more and 38 mN/m or less, 34 mN/m or more and 37 mN/m or less, or 35 mN/m or more and 37 mN/m or less.
According to an exemplary embodiment of the present invention, the low-density polyolefin elastomer may have a melting temperature of 50° C. or more and 125° C. or less.

According to an exemplary embodiment of the present invention, the thickness of the thin film foam tape may be 50 μm or more and 120 μm or less.

The thin film foam tape has an advantage that can be implemented as a thin film within the above range, even though it includes both an acrylic hot-melt resin and a polyolefin-based material. Furthermore, even if it is a thin film as in the above range, there is an advantage of implementing excellent tensile strength and durability.

According to an exemplary embodiment of the present invention, the degree of crosslinking of the thin film foam tape may be 60% or more, or 70% or more. Specifically, the crosslinking degree of the thin film foam tape may be 60% or more and 99% or less, 70% or more and 99% or less, 80% or more and 99% or less, 90% or more and 99% or less, or 95% or more and 99% or less.

In the present invention, the measurement of "crosslinking degree" may be a value measured by the xylene extraction method according to ASTM D2765.

When the crosslinking degree of the thin film foam tape is within the above range, the thin film foam tape can implement high thermal stability, thereby preventing meltdown even at a high temperature of about 200° C., thereby maintaining its shape.

According to an exemplary embodiment of the present invention, the hollow microspheres may have a hollow structure surrounded by a shell made of polymer or glass. Specifically, the hollow microspheres may be composed of a shell portion of an acrylic resin, a vinylidene chloride resin, and/or a styrene resin.

According to an exemplary embodiment of the present invention, the average diameter of the hollow microspheres may be 5 μm or more and 70 μm or less. Within the above range, the hollow microspheres may be uniformly dispersed within the thin film foam tape, and the thickness of the thin film foam tape may be easily controlled.

According to an exemplary embodiment of the present invention, the density of the hollow microspheres may be 0.01 g/cm 3 or more and 0.1 g/cm 3 or less, and when within the density range, the elastic properties of the thin film foam tape may be better implemented.

According to an exemplary embodiment of the present invention, in consideration of the foaming or bursting effect of the hollow microspheres, a foamable gas may be collected in the hollow portion. In this case, the type of gas to be used is not particularly limited, but the boiling point thereof is preferably relatively low, and specifically, may be butane, isobutane, pentane or isopentane.

According to an exemplary embodiment of the present invention, the hollow microspheres may be applied to the Expancel series manufactured by Akzo Nobel and the MSH series manufactured by Matsumoto, but are not limited thereto.

According to an exemplary embodiment of the present invention, the hollow microspheres may be included in the foamed or ruptured state in the thin film foam tape. Specifically, the foaming of the hollow microspheres means that the polymer material constituting the shell is not ruptured and is inflated within a certain range, and the rupture of the hollow microspheres means that the polymer material constituting the shell is partially or totally ruptured. This means that the sphere is inflated. The hollow microspheres may be foamed or ruptured in a mixing step through twin-screw extrusion in a method of manufacturing a thin film foam tape to be described later.

As the hollow microspheres exist in the foamed or ruptured state as described above in the thin-film foam tape, the thin-film foam tape is entirely composed of a foam structure, and excellent elasticity and hardness can be realized. In particular, since the hollow microspheres exist in a burst or foamed state, the flexibility and stress relaxation properties of the thin film foam tape can be remarkably increased.

According to an exemplary embodiment of the present invention, the content of the hollow microspheres may be 1 part by weight or more and 10 parts by weight or less based on the total weight of the acrylic hot-melt resin and the low-density polyolefin elastomer.

When the content of the hollow microspheres is within the above range, the surface of the thin film foam tape is uniformly formed, and at the same time, the flexibility and stress relaxation performance of the thin film foam tape can be effectively implemented.

An exemplary embodiment of the present invention provides a method of manufacturing the thin film foam tape.

Specifically, an exemplary embodiment of the present invention, an acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres; preparing a foam-forming composition comprising; A mixing step of melt-kneading the foam-forming composition through twin-screw extrusion; Coating the melt-kneaded foam-forming composition on a substrate by extrusion; And forming a thin film foam tape through electron beam crosslinking of the coated foam forming composition, wherein the thin film foam tape has a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less. to provide.

In the manufacturing method according to an exemplary embodiment of the present invention, the acrylic hot melt resin, the low density polyolefin elastomer, and the hollow microspheres are as described above.

According to an exemplary embodiment of the present invention, the foam-forming composition may be a solvent-free type. The foam-forming composition is a solvent-free type, and a separate drying process may be omitted, and the risk due to a volatile solvent during the process may be minimized.

In the mixing step, an acrylic hot-melt resin having poor compatibility with each other and a low-density polyolefin elastomer are melt-kneaded through twin-screw extrusion so that the respective advantages can be realized in a thin-film foam tape.

Further, through the mixing step, the foaming of the hollow microspheres is induced, thereby improving the flexibility and stress relaxation properties of the thin film foam tape.

According to an exemplary embodiment of the present invention, the mixing step may be melt-kneading at a temperature of 100°C or more and 200°C or less. Specifically, the mixing step may be melt-kneading at a temperature of 100°C or more and 170°C or less, or 120°C or more and 170°C or less.

In the above temperature range, the acrylic hot-melt resin and the low-density polyolefin elastomer may be uniformly kneaded in a twin screw extruder.

According to an exemplary embodiment of the present invention, the mixing step may be performed for a time of 1 minute or more and 10 minutes or less.

According to an exemplary embodiment of the present invention, the coating step may be to coat the melt-kneaded foam-forming composition on a substrate by extrusion. At this time, the substrate may be a release liner.

According to an exemplary embodiment of the present invention, the coating step may be to coat the melt-kneaded foam-forming composition on a substrate with a thickness of 50 μm or more and 120 μm or less using a T-die.

1 schematically shows a method of manufacturing a thin film foam tape according to an exemplary embodiment of the present invention. Specifically, FIG. 1 shows that a foam-forming composition is melt-kneaded through a twin-screw extruder, and then coated on a release liner, and then a thin film foam tape is manufactured through electron beam crosslinking. However, the present invention is not limited to the manufacturing method of FIG. 1.

The method of manufacturing a thin film foam tape according to the present invention can produce a foam tape obtained by mixing an acrylic hot melt resin and a polyolefin elastomer, which could not be produced before due to the problem of kneading between an acrylic hot melt resin and a polyolefin elastomer. There is an advantage that can be formed. Furthermore, the thin-film foam tape prepared as described above has the advantage of simultaneously realizing high adhesion performance of acrylic hot-melt resin and increasing modulus according to polyolefin elastomer, and increase in viscoelasticity ratio according to temperature due to excellent kneading property of acrylic hot-melt resin and polyolefin elastomer. There is this.

Hereinafter, examples will be described in detail to illustrate the present invention in detail. However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention is not construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely describe the present invention to those of ordinary skill in the art.

[ Example One]

100 parts by weight of a low-density polyethylene elastomer (DOW Chemical; Infuse 9507) having a density of 0.866 g/cm 3, 100 parts by weight of an acrylic hot melt resin prepared using 2-ethylhexyl acrylate and acrylic acid, and hollow microspheres (Matsumoto; MSH) 320) 5 parts by weight, 0.3 parts by weight of antioxidant (Iganox 1010), and 0.03 parts by weight of carbon black (Mitsubishi; MA600) as a colorant were added to a twin-screw extruder, melt-kneaded at 150°C, and T-die After forming a film on a release liner with a thickness of 100 μm through the film, electron beam crosslinking was performed at a dose of 80 kGy to prepare a thin film foam tape.

[ Example 2]

A thin film foam tape was prepared in the same manner as in Example 1, except that the content of the acrylic hot melt resin was adjusted to 300 parts by weight and the content of the hollow microspheres was adjusted to 10 parts by weight.

[ Comparative example One]

Low-density polyethylene elastomer with a density of 0.866 g/cm 3 (DOW Chemical; Infuse 9507) 100 parts by weight, hollow microspheres (Matsumoto; MSH 320) 2.5 parts by weight, antioxidant (Iganox 1010) 0.3 parts by weight and carbon black (Mitsubishi G.; MA600) A foam-forming composition containing 0.03 parts by weight was put into a twin-screw extruder, melt-kneaded at 150° C., and formed on a release liner with a thickness of 100 μm through a T-die, and then crosslinked with an electron beam at a dose of 80 kGy. Thus, a thin foam tape was prepared.

[ Comparative example 2]

100 parts by weight of an acrylic hot-melt resin prepared using 2-ethylhexyl acrylate and acrylic acid, 2.5 parts by weight of hollow microspheres (Matsumoto; MSH 320), 0.3 parts by weight of antioxidant (Iganox 1010), and carbon black (Mitsubishi G.; MA600) A foam-forming composition containing 0.03 parts by weight was put into a twin-screw extruder, melt-kneaded at 150° C., and formed on a release liner with a thickness of 100 μm through a T-die, and then crosslinked with an electron beam at a dose of 80 kGy. Thus, a thin foam tape was prepared.

[ Comparative example 3]

A thin film foam tape was prepared in the same manner as in Example 1, except that a low-density polyethylene elastomer (LG Chemical Co.; LC100) having a density of 0.903 g/cm 3 was used.

[ Experimental example 1]-Measurement of crosslinking degree

The crosslinking degree (gel fraction) of the thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3 was measured according to ASTM D2765. Specifically, the pulverized sample of 30 to 60 mesh was put into a 120 mesh wire mesh bag and extracted by boiling at 1 atmosphere (0.1 MPa) and 110° C. for 12 hours using xylene contained in a round flask connected to a condenser. . After extraction, the amount (mg) of the sample remaining in the wire mesh bag was measured, and the degree of crosslinking (gel fraction; %) was calculated using this, and the results are shown in Table 1 below.

[ Experimental example 2] - Peeling force Measure

After backing the thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3 to a 50 µm-thick polyethylene terephthalate (PET) film, a 2.5 cm × 11 cm tape strip polished glass Tensile tester (Instron) to be attached to the substrate, stored for 24 hours in an atmosphere of 25°C and 25 RH%, and pulled at a rate of 300 mm/min and a peeling angle of 90° in an atmosphere of 25°C and 25 RH% It was mounted and measured, and the results are shown in Table 1 below. .

[ Experimental example 3]-Tensile strength and fracture Elongation Measure

The tensile strength and elongation at break of the thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3 were measured according to ASTM D638 standards at 25°C and 50 RH% atmosphere. Specifically, the sample was cut into a "dog bone" shape with a width of 13 mm in the middle part, and the end of the sample was clamped with an Instron tensile tester and pulled at a crosshead speed of 50 cm per minute to be tensioned. The strength (kgf/cm2) and elongation at break (%) were measured and shown in Table 1 below.

[ Experimental example 4]-Measurement of recovery rate

The thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3 were prepared with a length of 50 mm and a width of 10 mm, and the prepared specimen was 100% at a speed of 20 mm/s in the longitudinal direction. After stretching, it was held for 5 seconds and left at 60° C. for 30 seconds, and the length was measured. At this time, using the length (L0) of the specimen before stretching, the length (a1) that has been stretched after stretching at a speed of 20mm/s in the longitudinal direction, and the length (a2) that has been stretched after standing at 60°C for 30 seconds The recovery rate was calculated according to, and the results are shown in Table 1 below.

[General Formula 1]

Recovery rate (%) = (a1-a2)/a1 × 100

[ Experimental example 5]-Surface energy measurement

The surface energy of the thin film foam tapes according to Examples 1, 2, and Comparative Examples 1 to 3 was based on the Owens-Wendt-Rabel-Kaelble method, and a drop shape analyzer (Drop Shape Analyzer, manufactured by KRUSS DSA100) It was measured using. Specifically, in an atmosphere of 25° C. and 50 RH%, deionized water and methylene iodide were dropped on the surface of the sample 10 times to obtain the average value of the contact angle, and the numerical value was substituted for the Owens-Wendt-Rabel-Kaelble method The values obtained by calculating the surface energy are shown in Table 1 below.

[ Experimental example 6]- Viscoelastic ratio Measure

The viscoelastic ratio of the thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3 was obtained by evaluating the extrusion flowability of the thin film foam tape using DMA (dynamic mechanical behavior analysis). Specifically, by measuring the storage modulus (STORAGE MODULUS, G') and loss modulus (LOSS MODULUS, G``) at 150, which is the processing temperature of the thin film foam tape, the viscoelastic ratio (G``/G', phase angle) is measured. ) Was calculated and shown in Table 1 below.

Table 1 below shows the physical properties of the thin film foam tapes according to Example 1, Example 2, and Comparative Examples 1 to 3.

Degree of crosslinking
(%) Peeling force
(N/2.5cm) The tensile strength
(kgf/㎠) Elongation at break
(%) Restoration rate
(%) Surface energy
(mN/m) Viscoelastic ratio
(@150℃) Example 1 95 12 10.6 920 99 35.2 47.8 Example 2 96 15 10.5 880 96 36.8 45.1 Comparative Example 1 95 2 10.9 1000 98 32.2 48.0 Comparative Example 2 95 10 2.1 200 72 40.1 37.4 Comparative Example 3 95 8 11.2 900 70 34.9 44.2

According to Table 1, it can be seen that Comparative Example 3, in which the density of the acrylic hot melt resin exceeds 0.9 g/cm 3, has a very low recovery rate. On the other hand, in the case of Examples 1 and 2, it can be seen that since it has a very good recovery rate, it has high elasticity and elasticity. Further, it can be seen that Comparative Example 1 not including the acrylic hot-melt resin exhibited very low peel strength, and Comparative Example 2 not containing the low-density polyethylene elastomer exhibited very low tensile strength.

In the case of Comparative Example 2 using only acrylic hot-melt resin, the viscoelastic ratio was low, so the processing efficiency was not good when manufacturing the thin film foam tape, and the adhesion to the adherend was relatively poor due to high surface energy. On the contrary, in Examples 1 and 2, the viscoelastic ratio was high, so that the thin-film foam tape could be easily manufactured as a thin film, and the adhesion to the adherend was excellent because it had a relatively low surface energy.

Claims (12)

Acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres,
It has a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less,
Thin film foam tape having a thickness of 50 μm or more and 120 μm or less. The method according to claim 1,
The weight ratio of the acrylic hot-melt resin and the low-density polyolefin elastomer is 4:6 to 9:1 of the thin film foam tape. The method according to claim 1,
The thin film foam tape has a tensile strength of 8 kgf/cm2 or more. The method according to claim 1,
The thin film foam tape that the elongation at break of the thin film foam tape is 800% or more. The method according to claim 1,
The thin film foam tape has a peeling force of the thin film foam tape on the glass substrate of 8 N/2.5 cm or more and 20 N/2.5 cm or less. The method according to claim 1,
The surface energy of the thin film foam tape is 34 mN/m or more and 40 mN/m or less. The method according to claim 1,
The low-density polyolefin elastomer is a thin film foam tape having a melting temperature of 50° C. or more and 125° C. or less. delete Acrylic hot melt resin; A low density polyolefin elastomer of 0.9 g/cm 3 or less; And hollow microspheres; preparing a foam-forming composition comprising;
A mixing step of melt-kneading the foam-forming composition through twin-screw extrusion;
A coating step of extruding the melt-kneaded foam-forming composition to coat a substrate with a thickness of 50 μm or more and 120 μm or less; And
Including; forming a thin film foam tape through electron beam crosslinking of the coated foam-forming composition,
The thin film foam tape has a density of 0.3 g/cm 3 or more and 0.8 g/cm 3 or less. The method of claim 9,
The foam-forming composition is a method of manufacturing a thin film foam tape that is a solvent-free type. The method of claim 9,
The mixing step is a method of manufacturing a thin film foam tape by melt-kneading at a temperature of 100°C or more and 200°C or less. The method of claim 9,
The coating step is a method of manufacturing a thin film foam tape by coating the melt-kneaded foam-forming composition on a substrate using a T-die.

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