Swelling tape for filling gap

Abstract

A swelling tape for filling a gap and a method of filling a gap are provided. The swelling tape can be applied within the gap having a fluid to realize a 3D shape thereby filling the gap, and be used to fix a subject forming the gap as necessary.

Claims

1. A swelling tape for filling a gap, comprising: a substrate layer that deforms along a longitudinal direction when coming in contact with a fluid; and a pressure-sensitive adhesive layer formed on one surface of the substrate layer in a direction parallel to a longitudinal direction of the substrate layer, wherein the substrate layer is a layer selected from the group consisting of: a cast layer of a composition consisting essentially of 30 parts by weight to 99 parts by weight of an energy ray-polymerizable acrylate compound and 1 part by weight to 70 parts by weight of a radical-polymerizable diluents; a cast layer of a composition comprising a polyol and an isocyanate compound; a layer comprising thermoplastic polyurethane; and a layer comprising a cellulose acetate resin or a cellulose alkylate resin, wherein the substrate layer forms a three-dimensional structure when coming in contact with a fluid, wherein the three-dimensional structure includes a shape protruding along the vertical direction and wherein a plurality of the shapes are included in the three-dimensional structure, and wherein the substrate layer has a strain of at least 10% in a longitudinal direction according to Equation 1:
Strain in Longitudinal direction=(L.sub.2?L.sub.1)/L.sub.1?100,[Equation1] wherein L.sub.1 is an initial length of the substrate layer before the substrate layer comes in contact with the fluid; and L.sub.2 is a length of the substrate layer, which is measured after the substrate layer comes in contact with the fluid at room temperature or 60? C. for 24 hours.

2. The swelling tape of claim 1, wherein the pressure-sensitive adhesive layer has a peel strength of 100 gf/25 mm or more at room temperature, which is measured at a peel rate of 5 mm/sec and a peel angle of 180? to a glass plate or any one subject that forms a gap.

3. The swelling tape of claim 1, wherein the pressure-sensitive adhesive layer includes an acrylic pressure-sensitive adhesive, a urethane pressure-sensitive adhesive, an epoxy pressure-sensitive adhesive, a silicon pressure-sensitive adhesive, or a rubber pressure-sensitive adhesive.

4. A method of filling a gap, which is formed by a first substrate and a second substrate spaced apart from the first substrate, comprising: attaching a pressure-sensitive adhesive layer of the swelling tape according to claim 1 to the first substrate or the second substrate; and deforming the substrate layer in a longitudinal direction by bringing the substrate layer of the swelling tape in contact with a fluid.

5. The method of claim 4, wherein one of the first and second substrates is an electrode assembly and the other is a can receiving the assembly.

6. The swelling tape of claim 1, wherein the substrate layer is the cast layer of the composition comprising the polyol and the isocyanate compound, and wherein the polyol includes an alkylene glycol, a dialkylene glycol, a benzenediol, a benzenetriol, a dialcohol amine, a trialcohol amine, arabitol, mannitol, isomalt, glycerol, xylitol, sorbitol, maltitol, erythritol, ribitol, dulcitol, lactitol, threitol, iditol or polyglycitol.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The above and other objects, features and advantages of the present invention will become more apparent to those of ordinary skill in the art by describing in detail exemplary embodiments thereof with reference to the attached drawings, in which:

(2) FIG. 1 is a schematic diagram showing a process of forming the swelling tape into a 3D shape;

(3) FIG. 2 is a schematic diagram showing the swelling tape; and

(4) FIG. 3 is a schematic diagram showing a process of forming the swelling tape into a 3D shape in a process of manufacturing a battery.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

(5) Hereinafter, exemplary embodiments of the present invention will be described in detail. However, the present invention is not limited to the embodiments disclosed below, but can be realized in various forms. The following embodiments are described in order to enable those of ordinary skill in the art to embody and practice the present invention.

(6) Although the terms first, second, etc. may be used to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of exemplary embodiments. The term and/or includes any and all combinations of one or more of the associated listed items.

(7) It will be understood that when an element is referred to as being connected or coupled to another element, it can be directly connected or coupled to the other element or intervening elements may be present. In contrast, when an element is referred to as being directly connected or directly coupled to another element, there are no intervening elements present.

(8) The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of exemplary embodiments. The singular forms a, an and the are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms comprises, comprising, includes and/or including, when used herein, specify the presence of stated features, integers, steps, operations, elements, components and/or groups thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.

(9) With reference to the appended drawings, exemplary embodiments of the present invention will be described in detail below. To aid in understanding the present invention, like numbers refer to like elements throughout the description of the figures, and the description of the same elements will be not reiterated.

(10) Hereinafter, the swelling tape will be described in further detail with reference to Examples and Comparative Examples, but the categories of the swelling tape will not be limited to the following Examples.

(11) As described below, physical properties in Examples and Comparative Examples were evaluated by the following methods.

(12) 1. Measurement of Strain of Substrate Layer in Longitudinal Direction

(13) A substrate layer was cut to be 10 mm wide and 50 mm long to prepare a specimen. The prepared specimen was impregnated in a carbonate-based electrolyte, and then was maintained at room temperature for 1 day in a sealed state. Then, the specimen was removed from the electrolyte; a height of the specimen was measured; and then a strain of the substrate layer in a longitudinal direction was measured based on the following Equation A:
Strain in Longitudinal direction=(L.sub.2?L.sub.1)/L.sub.1?100[Equation A]

(14) In Equation A, L.sub.1 is an initial length of the substrate layer in a longitudinal direction before the substrate layer is impregnated in an electrolyte, that is, 50 mm; and L.sub.2 is a length of the substrate layer in a longitudinal direction after the substrate layer is impregnated in an electrolyte.

(15) 2. Measurement of Peel Strength of Swelling Tape

(16) A swelling tape was cut to be 25 mm wide and 200 mm long to prepare a specimen. The specimen was attached via a pressure-sensitive adhesive layer to a glass plate using a 2-kg rubber roller, and then stored at room temperature for 2 hours. Then, a peel strength was measured while a swelling tape was peeled with a peel rate of 5 mm/sec and a peel angle of 180? using a tensile tester.

(17) 3. Evaluation of Probability of Realizing a 3D Shape by Swelling Tape

(18) The batteries manufactured in Examples and Comparative Examples were stored at room temperature for 1 day, and then were disassembled to remove electrode assemblies. Probability of realization of 3D shapes was evaluated by evaluating conditions of swelling tapes that were attached to the electrode assemblies according to the following criteria:

(19) <Evaluation Criteria of Probability of Realizing 3D Shape>

(20) ?: A 3D shape of a swelling tape is observed.

(21) ?: A 3D shape of a swelling tape is not observed.

(22) x: A 3D shape of a swelling tape is not observed and the tape is peeled from an electrode assembly.

(23) 4. Evaluation of Ability of Swelling Tape to Fill Gap (Ability to Prevent Movement of Electrode Assembly)

(24) An ability of a swelling tape to fill a gap may be measured using a method of evaluating a property of preventing a movement of an electrode assembly. For example, the above-described method includes a method of evaluating a residual vibration and a method of evaluating a residual impact. The method of evaluating the residual vibration is performed according to a vibration test of UN38.3 standard and it is judged that a terminal is disconnected by a movement when a power of a battery is not sensed after evaluation. For the way of evaluating the residual impact, a terminal is judged to be disconnected by a movement when a power of a battery is not sensed a fixed time after a battery is added to an octagonal cylinder and then is spun. The abilities of the swelling tapes to fill gaps, which were evaluated as described above, were evaluated according to the following criteria:

(25) <Evaluation Criteria of Ability to Fill Gap>

(26) ?: A power of a battery is measured after evaluations of a residual vibration and a residual impact.

(27) ?: A power of a battery is measured after evaluations of a residual vibration and a residual impact, but the resistivity is increased 10% or more.

(28) x: A power of a battery is not measured after evaluations of a residual vibration and a residual impact.

Preparative Example 1. Manufacture of Urethane-Based Substrate Layer

(29) A film having a thickness of approximately 40 ?m was formed with a composition including butanediol polyol and methylene diphenyl diisocyanate with an equivalent ratio of approximately 1:1 of the hydroxyl group of the polyol and the isocyanate group of the diisocyante, using T-die, and then cured to manufacture a substrate. A strain of the manufactured substrate in a longitudinal direction was approximately 100%.

Preparative Example 2. Manufacture of Urethane Acrylic-Based Substrate Layer

(30) After mixing 40 parts by weight urethane acrylate and 70 parts by weight isobornyl acrylate (IBOA) as a diluent, 0.5 parts by weight of a photoinitiator (Irgacure-184, 1-hydroxyl cyclohexyl phenylketone) was further added, mixed, and defoamed to prepare a composition. The prepared composition was coated on a polyester release film to have a thickness of approximately 40 ?m using a bar coater. The polyester release film was covered on the coating layer in order to prevent contact of oxygen and then the composition was cured by irradiation with light of the UV-A region at a radiation intensity of 800 mJ/cm.sup.2 using a metal halide lamp to manufacture a substrate layer. A strain of the manufactured substrate layer in a longitudinal direction was approximately 43%.

Preparative Example 3. Manufacture of Epoxy Acrylic-Based Substrate Layer

(31) After mixing 60 parts by weight epoxy acrylate, 38 parts by weight IBOA, and 2 parts by weight acrylic acid, 1.2 parts by weight of a photoinitiator (Irgacure-184, 1-hydroxyl cyclohexyl phenylketone) was further added, mixed, and defoamed to prepare a composition. The prepared composition was coated on a polyester release film to have a thickness of approximately 40 ?m using a bar coater. The polyester release film was covered on the coating layer in order to prevent contact of oxygen and then the composition was cured by irradiation with light of the UV-A region at a radiation intensity of 800 mJ/cm.sup.2 using a metal halide lamp to manufacture a substrate layer. A strain of the manufactured substrate layer in a longitudinal direction was approximately 11%.

Preparative Example 4. Manufacture of Cellulose-Based Substrate Layer

(32) A raw material including a cellulose acetate propionate compound having a number average molecular weight (Mn) of 70,000 as measured by GPC was molded as a substrate layer having a thickness of approximately 40 ?m using T-die. A strain of the manufactured substrate layer in a longitudinal direction was approximately 20%.

Example 1. Manufacture of Swelling Tape

(33) A swelling tape was manufactured by forming a pressure-sensitive adhesive layer having a thickness of 15 ?m and a peel strength of 1,900 gf/25 mm with respect to a glass plate as an acrylic-based pressure-sensitive adhesive layer including an acrylic adhesive resin, which is crosslinked with an isocyanate crosslinking agent, on one surface of the urethane-based substrate layer (thickness of 40 ?m) manufactured in Preparative Example 1.

(34) Manufacture of Electrode Assembly and Battery

(35) A swelling tape was attached to cover approximately 50% of the outer circumferential surface of a jelly roll-shaped electrode assembly (cross-sectional diameter of 17.2 mm) in which the electrode assembly includes a negative electrode, a positive electrode and a separator, and then the electrode assembly was inserted into a cylindrical can (cross-sectional diameter of 17.5 mm) Subsequently, a carbonate-based electrolyte was injected into the can, which was then sealed to complete a battery.

Examples 2 to 4 and Comparative Examples 1 and 2

(36) Swelling tapes and batteries were manufactured in the same manner as in Example 1, except that substrate layers were changed as shown in the following Table 1, and the pressure-sensitive adhesive layer based on the same composites as in Example 1 was used; but peel strengths of the pressure-sensitive adhesive layers to a glass were changed as shown in the following Table 1 when the swelling tapes were manufactured.

(37) TABLE-US-00001 TABLE 1 Comparative Examples Examples 1 2 3 4 1 2 Substrate Kinds Preparative Preparative Preparative Preparative PP PET layer Example 1 Example 2 Example 3 Example 4 Strain 100 43 11 20 0 0 Pressure- Composition Acrylic Acrylic Acrylic Acrylic Acrylic Acrylic sensitive Peel 1900 900 150 2000 1500 60 adhesive strength layer Strain: Strain of Substrate layer in Longitudinal direction (Unit: %) Peel strength: Peel strength to Glass Plate (Unit: gf/25 mm) PP: Polypropylene Substrate layer with Strain of 0% in Longitudinal direction (Thickness: 40 ?m) PET: Polyethylene Terephthalate Substrate layer with Strain of 0% in Longitudinal direction (Thickness: 25 ?m)

(38) Physical Properties measured for the above Examples and Comparative Examples are summarized and listed in the following Table 2.

(39) TABLE-US-00002 TABLE 2 Comparative Examples Examples 1 2 3 4 1 2 Probability of realization of ? ? ? ? ? ? 3D shape Ability to Fill Gap (Ability ? ? ? ? X X to Prevent Movement)

(40) The swelling tape can be, for example, applied within a gap having a fluid to realize a 3D shape thereby filling the gap and be used to fix a subject forming a gap as necessary.

(41) While the invention has been shown and described with reference to certain exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the scope of the invention as defined by the appended claims.