Coating system

Abstract

To provide a coating system that preferably discharge a resin containing a hollow filler.SOLUTION: A coating system includes: a pressure-feeding pump 100 capable of feeding a viscous material with pressure; a leveling part 200 for leveling a flow rate of the viscous material that is fed by the pressure-feeding pump; a dispenser 300 feeding the viscous material that is leveled by the leveling part and having a structure of a rotary positive displacement-type uniaxial eccentric screw pump; and a coating valve 400 for coating the viscous material, which is fed from the dispenser, in a planar form.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a coating system. [Background technology]

[0002] Research and development is being conducted daily on systems for applying viscous materials. The technology related to the application system includes a dispensing unit including a discharge nozzle, a moving device that moves the dispensing unit to any position, a storage device that stores the dispensing unit after it has been removed from the moving device, and a temperature control device that adjusts the temperature of the highly viscous fluid in the dispensing unit, with the temperature control head of the temperature control device being installed in the storage device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-216148 Summary of the Invention [Problem to be solved by the invention]

[0004] The present inventors have been conducting extensive research into a coating system such as that disclosed in Patent Document 1, which is suitable for discharging a resin containing hollow fillers.

[0005] Therefore, an object of the present invention is to provide a coating system suitable for discharging a resin containing hollow fillers. [Means for solving the problem]

[0006] A coating system according to one aspect of the present invention that solves the above-described problems includes a pressure pump, a leveling unit, a dispenser, and a coating valve. The pressure pump is configured to be able to pump a viscous material. The leveling unit is configured to level the flow rate of the viscous material dispensed by the pressure pump. The dispenser dispenses the viscous material leveled by the leveling unit and has a rotary positive displacement uniaxial eccentric screw pump structure. The coating valve is configured to apply the viscous material dispensed from the dispenser in a planar manner. [Effects of the Invention]

[0007] According to the application system of the present invention, it is possible to suitably apply a resin containing hollow fillers. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a perspective view schematically illustrating a coating system according to an embodiment of the present invention. [Figure 2] FIG. 2 is a diagram schematically illustrating the inside of a leveling unit. [Figure 3] FIG. 2 is a diagram showing the inside of a coating valve that constitutes the coating system. [Figure 4] 1 is an exploded perspective view illustrating stacking of a battery pack including a cushioning material containing a viscous material formed by an application system. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The embodiments shown here are merely examples for embodying the technical concept of the present invention and are not intended to limit the present invention. Furthermore, all other embodiments, examples, and operational techniques that can be conceived by those skilled in the art without departing from the spirit of the present invention are included within the scope and spirit of the present invention, as well as within the scope of the claims and their equivalents.

[0010] Furthermore, for the convenience of illustration and ease of understanding, the drawings attached to this specification may be represented schematically with the scale, aspect ratio, shape, etc. appropriately changed from the actual product, but these are merely examples and do not limit the interpretation of the present invention.

[0011] In the following description, ordinal numbers such as "first" and "second" are used, but unless otherwise specified, they are used for convenience and do not stipulate any order.

[0012] FIG. 1 is a perspective view that schematically shows a coating system 1 according to one embodiment of the present invention. FIG. 2 is a view that schematically shows the interior of a leveling unit 200 that constitutes the coating system 1. FIG. 3 is a view that shows the interior of a coating valve 400 that constitutes the coating system 1. FIG. 4 is an exploded perspective view that shows the stacking of a battery pack B that includes a buffer material b2 that is formed by the coating system 1 and that contains a viscous material. The coating system 1 can be used to form the buffer material b2 of a battery pack B that is mounted on an automobile or the like. The buffer material b2 that is formed by the coating system 1 and that contains a viscous material can be disposed as a component of the battery pack B between adjacent electric cells b1 (cells) in the stacking direction or between a module case and an electric cell b1 (cell) (see FIG. 4).

[0013] As shown in FIG. 1, the coating system 1 according to this embodiment includes a pressure pump 100, a leveling unit 200, a dispenser 300, and a coating valve 400. The viscous material applied by the coating system 1 includes a resin and a hollow filler. The viscous material has a specific gravity of less than 1.00. This will be described in detail below.

[0014] The viscous material is a photocurable composition prepared by combining components (A) to (G) and optional components, with component (A) described below as an essential component. Here, component (A) corresponds to the "hollow filler," and the composition of components (B) to (F) and optional components corresponds to the "resin."

[0015] Component (A) is a hollow filler, which refers to a hollow body having a hollow portion and is a particle formed from an inorganic or organic material. In particular, by including component (A), the cured product obtained by curing the photocurable composition according to the present invention generates a small reaction force even when compressed over a wide range of compression ratios (especially high compression ratios). Furthermore, by combining component (A) with a resin, not only can a cured product generating such a small reaction force be obtained, but the photocurable composition can also be rapidly cured by photocuring.

[0016] Component (A) is formed from glass or a synthetic resin. While the synthetic resin is not particularly limited, it is preferably a thermoplastic resin, and more preferably a polymer (homopolymer) of at least one monomer selected from the group consisting of vinylidene chloride, acrylonitrile, methacrylonitrile, acrylic acid esters (acrylates), and methacrylic acid esters (methacrylates), or a copolymer of two or more monomers selected from the above. These organic resins may be used alone or in combination of two or more. From the viewpoint of the toughness (strength) of component (A), the synthetic resin constituting component (A) is preferably a polymer (polyacrylonitrile resin) or copolymer containing acrylonitrile as a structural unit, more preferably a copolymer containing acrylonitrile as a structural unit, and particularly preferably an acrylonitrile-methacrylonitrile-methyl methacrylate copolymer. That is, component (A) is preferably composed of an acrylonitrile-methacrylonitrile-methyl methacrylate copolymer.

[0017] Component (A) is preferably surface-treated to improve compatibility with the resin. Here, the term "component (A)" includes the surface treatment. The type of surface treatment is not particularly limited, but the component may be surface-treated with a silane coupling agent, fatty acid, or the like, or may have an inorganic filler, such as calcium carbonate powder, attached to its surface. It is particularly preferred that component (A) be a hollow filler with calcium carbonate powder attached to its surface. These types of surface treatment may be used alone or in combination.

[0018] The shape of component (A) is not particularly limited, but is essentially spherical. A spherical shape is preferred, not only because it reduces the reaction force of the cured product during compression but also because it facilitates uniform dispersion throughout the composition. Here, "spherical" refers to a shape with an aspect ratio of 1.0 to 2.0, preferably 1.0 to 1.5, but does not necessarily mean a perfect sphere. In the case of spherical fillers, the aspect ratio refers to the ratio of the major axis to the minor axis. The average particle size of component (A) is not particularly limited, but is preferably 5 to 300 μm, more preferably 10 to 200 μm, even more preferably 50 to 150 μm, particularly preferably 60 to 130 μm, and most preferably 70 to 100 μm. The average particle size of component (A) can be determined using a particle size distribution analyzer employing analytical techniques such as laser diffraction. By having the average particle size of component (A) within the above range, a cured product with low reaction force can be obtained over an even wider range of compression ratios (compression range).

[0019] The true specific gravity of component (A) is not particularly limited, but is, for example, 0.03 to 0.50 g / cm 3 It is preferable that the concentration is 0.05 to 0.40 g / cm 3 It is more preferable that the concentration is 0.07 to 0.30 g / cm 3It is particularly preferred that the true specific gravity of component (A) is determined in accordance with JIS Z 8807:2012. When the true specific gravity of component (A) is within the above range, a cured product with low repulsion can be obtained over an even wider range of compression ratios (compression range). By adding component (A), the specific gravity of the photocurable composition before curing can be made less than 1.00.

[0020] The component (A) may be either a synthetic product or a commercially available product. Examples of commercially available products of the component (A) include EMC-40B, EMC-80B, and EMC-120α (manufactured by Nippon Phillite Co., Ltd.).

[0021] The content of component (A) is not particularly limited, but is preferably 3 to 80 parts by mass, more preferably 5 to 50 parts by mass, particularly preferably 8 to 30 parts by mass, and most preferably 10 to 20 parts by mass, per 100 parts by mass of the total mass of the photocurable composition. The content of component (A) is also not particularly limited, but is preferably 3 to 70 parts by mass, more preferably 5 to 60 parts by mass, particularly preferably 10 to 50 parts by mass, and most preferably 20 to 30 parts by mass, per 100 parts by mass of the combined total of components (B) and (C), described below. The above component (A) may be used alone, or two or more types may be used in combination. When two or more types are used in combination, the content of component (A) refers to the combined amount.

[0022] Component (B) is a urethane (meth)acrylate. Monofunctional urethane (meth)acrylates having one (meth)acryloyl group in the molecule are particularly preferred. By combining components (A) and (B), the reaction force generated in the cured product can be reduced even when the cured product is compressed over a wide range of compression ratios (compression range).

[0023] Here, the urethane (meth)acrylate of component (B) is an ester compound having a urethane bond formed by reacting an isocyanate group with a hydroxy group, and a (meth)acryloyl group. That is, the urethane (meth)acrylate is a (meth)acrylic acid ester having a urethane bond. The number of urethane bonds in component (B) may be one or more per molecule, and the number of (meth)acryloyl groups per molecule is one or more, most preferably one per molecule. The (meth)acryloyl group may be contained in the compound in the form of a (meth)acryloyloxy group. When a monofunctional urethane (meth)acrylate is used, the reaction force of the cured product of the photocurable composition is not high. Furthermore, from the viewpoint of reducing the compression set of the resulting cured product, the (meth)acryloyl group contained in component (B) is preferably an acryloyl group. Here, the "low compression set" of a certain material refers to the material having a high recovery force when compressed for a long period of time. Because of these properties, the photocurable composition (and its cured product) according to the present invention can be used, for example, as a buffer material. Since the reactivity of acryloyl groups is higher than that of methacryloyl groups, it is believed that when the (meth)acryloyl groups contained in component (B) are acryloyl groups, the compression set will be small, as described above. To improve the desired effects, the monofunctional urethane (meth)acrylate used as component (B) is preferably a monofunctional urethane (meth)acrylate oligomer. In this specification, the term "oligomer" refers to a polymer in which two to several tens of monomer units (including monomer units other than (meth)acrylate monomers) are repeated, and which has a weight-average molecular weight of 1,000 (1,000) or more.

[0024] The (B) component may contain a structure other than a urethane bond and a (meth)acryloyl group, such as a polyester skeleton, a polycaprolactone skeleton, a polycarbonate skeleton, or a polyether skeleton. One or more of these skeletons may be present in a single molecule, or two or more may be present in combination. Among these, from the viewpoint of further enhancing the desired effects, the (B) component preferably has a polyether skeleton. In this specification, the term "polyether skeleton" refers to a skeleton having an alkylene oxide, such as polyethylene oxide, polypropylene oxide, or polybutylene oxide, as a repeating unit. From the viewpoint of further enhancing the desired effects, the (B) component is preferably a monofunctional urethane (meth)acrylate oligomer having a polyether skeleton (polyether-based monofunctional urethane (meth)acrylate oligomer), and more preferably a monofunctional urethane acrylate oligomer having a polyether skeleton.

[0025] The method for producing component (B) is not particularly limited, but examples thereof include a method of reacting a polyol compound having a hydroxyl group with a (meth)acrylate having an isocyanate group, or a method of reacting a polyol compound having a hydroxyl group, a polyisocyanate compound, and a (meth)acrylate having a hydroxyl group, etc. These reactions are preferably carried out in the presence of a catalyst.

[0026] The polyol compound having a hydroxyl group is not particularly limited, but examples thereof include polyester polyols, polycarbonate polyols, polyether polyols such as polyethylene oxide, polypropylene oxide, and polybutylene glycol. The number of repeating units of alkylene oxide contained in the polyether polyol is not particularly limited, but is, for example, 3 to 500, more preferably 5 to 100, and particularly preferably 10 to 50.

[0027] The (meth)acrylate having an isocyanate group is not particularly limited, but examples thereof include 2-isocyanatoethyl (meth)acrylate and 2-(2-(meth)acryloyloxyethyloxy)ethyl isocyanate.

[0028] The polyisocyanate compound is not particularly limited, and examples thereof include aromatic polyisocyanates such as 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 1,3-xylylene diisocyanate, 1,4-xylylene diisocyanate, tetramethylxylylene diisocyanate, diphenylmethane diisocyanate, naphthalene-1,5-disocyanate, and triphenylmethane triisocyanate; isophorone diisocyanate, bis( Examples of suitable polyisocyanates include alicyclic polyisocyanates such as 4-isocyanatocyclohexyl)methane, 1,3-bis(isocyanatomethyl)cyclohexane, 1,4-bis(isocyanatomethyl)cyclohexane, norbornane diisocyanate, and bicycloheptane triisocyanate; and linear or branched aliphatic polyisocyanates such as hexamethylene diisocyanate, 1,3,6-hexamethylene triisocyanate, and 1,6,11-undeca triisocyanate. Among these, from the viewpoint of obtaining a flexible cured product, it is preferable that the polyisocyanate compound be selected from linear or branched aliphatic polyisocyanates and alicyclic polyisocyanates. These compounds may be used alone or in combination.

[0029] The (meth)acrylate having a hydroxyl group is not particularly limited, but examples thereof include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxycyclohexyl (meth)acrylate, 1,6-hexanediol mono(meth)acrylate, neopentyl glycol mono(meth)acrylate, (poly)ethylene glycol mono(meth)acrylate, (poly)propylene glycol mono(meth)acrylate, and pentaerythritol tri(meth)acrylate. Among these, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, and 4-hydroxycyclohexyl (meth)acrylate are preferred from the viewpoint of obtaining a cured product with excellent flexibility. These may be used alone or in combination.

[0030] Examples of catalysts used in the synthesis of component (B) include lead oleate, antimony trichloride, triphenylaluminum, trioctylaluminum, tetrabutyltin, dibutyltin dilaurate, copper naphthenate, zinc naphthenate, zinc octylate, zinc octenate, zirconium naphthenate, cobalt naphthenate, tetra-n-butyl-1,3-diacetyloxydistannoxane, triethylamine, 1,4-diaza[2,2,2]bicyclooctane, and N-ethylmorpholine. Among these, dibutyltin dilaurate, zinc naphthenate, zinc octylate, and zinc octenate are preferred because they cure rapidly even with a small cumulative dose of irradiated light and produce a cured product with low elasticity. The amount of these catalysts added is preferably 0.0001 to 10 parts by mass per 100 parts by mass of the total mass of the reactants. The reaction temperature is usually 10 to 100°C, and it is particularly preferred to carry out the reaction at 30 to 90°C.

[0031] The weight-average molecular weight of component (B) is not particularly limited. Because photocuring allows for rapid production of a cured product that exhibits low repulsion over a wide range of compression ratios (compression range), the weight-average molecular weight of component (B) is preferably, for example, 1,000 to 300,000 (1,000 to 300,000), more preferably 3,000 to 50,000 (3,000 to 50,000), and particularly preferably 5,000 to 40,000 (5,000 to 40,000). Unless otherwise specified, the weight-average molecular weight used herein is a value calculated using size exclusion chromatography (SEC) in terms of standard polystyrene.

[0032] The content of component (B) is not particularly limited, but is preferably 20 to 90 parts by mass, more preferably 30 to 85 parts by mass, even more preferably 40 to 80 parts by mass, particularly preferably 50 to 75 parts by mass, and most preferably 60 to 70 parts by mass, per 100 parts by mass of the total of component (B) and component (C), described below. By keeping the content within the above range, a photocurable composition can be obtained that can more quickly produce a cured product upon photocuring and that exhibits low repulsion over a wide range of compression ratios (compression range). The component (B) may be used alone, or two or more types may be used in combination. When two or more types are used in combination, the content of component (B) refers to the total amount.

[0033] Component (C) is a monofunctional (meth)acrylic monomer, excluding component (B). Addition of component (C) improves photocurability. A cured product with low repulsion can be obtained over a wide range of compression ratios (compression ranges). Here, a monofunctional (meth)acrylic monomer is a compound having one (meth)acryloyl group. The (meth)acryloyl group may be contained in the monomer in the form of a (meth)acryloyloxy group. Compounds having one or more urethane bonds and one (meth)acryloyl group per molecule (but ester compounds) are included in the above-mentioned component (B), but are not included in component (C).

[0034] Furthermore, for the purpose of improving photocurability, the (meth)acryloyl group contained in component (C) is preferably an acryloyl group, which also has the advantage of increasing the reaction rate and reducing the compression set of the resulting cured product.

[0035] The monofunctional (meth)acrylic monomer as component (C) is preferably a monofunctional (meth)acrylate monomer (i.e., an ester compound having one (meth)acryloyloxy group, a (meth)acrylic acid ester) in order to improve the desired effect.

[0036] Component (C) may contain a structure other than a (meth)acryloyl group. From the viewpoint of further improving the intended effects, it is preferable that component (C) has a polyether skeleton as such a structure. The definition of "polyether skeleton" is as described in the section on component (B) above. The number of repeating units of alkylene oxide constituting the polyether skeleton is not particularly limited, but is, for example, 2 to 300, preferably 2 to 100, more preferably 2 to 30, and particularly preferably 2 to 10. Furthermore, the number of carbon atoms constituting the alkylene oxide is not particularly limited, but the number of carbon atoms in one repeating unit is preferably 2 to 10, more preferably 2 to 5, particularly preferably 2 to 4, and most preferably 2. That is, the polyether skeleton contained in component (C) is preferably a polyethylene oxide skeleton.

[0037] The molecular weight of component (C) is not particularly limited, but from the viewpoint of improving the curability of the photocurable composition, it is preferably less than 1,000, more preferably 500 or less, and particularly preferably 300 or less. Furthermore, from the viewpoint of excellent compatibility with component (B), the molecular weight of the compound of component (C) is preferably greater than 100, more preferably 130 or more. Herein, the molecular weight of a compound (low molecular weight compound) can be measured by a known method such as gas chromatography-mass spectrometry (GC-MS). Furthermore, if it is not possible to measure by this method, the molecular weight can be determined by identifying the structure of the compound by a method such as NMR, and then performing calculations based on this structure.

[0038] The component (C) is not particularly limited, and examples thereof include methoxydiethylene glycol mono(meth)acrylate, methoxytriethylene glycol mono(meth)acrylate, methoxytetraethylene glycol mono(meth)acrylate, methoxypentaethylene glycol mono(meth)acrylate, methoxyhexaethylene glycol mono(meth)acrylate, methoxyheptaethylene glycol mono(meth)acrylate, methoxyhectaethylene glycol mono(meth)acrylate, methoxyoctaethylene glycol mono(meth)acrylate, methoxynonaethylene glycol mono(meth)acrylate, methoxydecaethylene glycol mono(meth)acrylate, methoxytripropylene glycol mono(meth)acrylate, methoxytetrapropylene glycol mono(meth)acrylate, methoxypentapropylene glycol mono(meth)acrylate, methoxyhexapropylene glycol mono(meth)acrylate, methoxyheptapropylene glycol mono(meth)acrylate, methoxyhectapropylene glycol mono(meth)acrylate, Methoxyoctapropylene glycol mono(meth)acrylate, methoxynonapropylene glycol mono(meth)acrylate, methoxydecapropylene glycol mono(meth)acrylate, methoxytributylene glycol mono(meth)acrylate, methoxytetrabutylene glycol mono(meth)acrylate, methoxypentabtylene glycol mono(meth)acrylate, methoxyhexabtylene glycol mono(meth)acrylate, methoxyheptabtylene glycol mono(meth)acrylate, methoxyhectabtylene glycol Lithium mono(meth)acrylate, methoxyoctabutylene glycol mono(meth)acrylate, methoxynonabutylene glycol mono(meth)acrylate, methoxydecabutylene glycol mono(meth)acrylate, ethoxydiethylene glycol mono(meth)acrylate, ethoxytriethylene glycol mono(meth)acrylate, ethoxytetraethylene glycol mono(meth)acrylate, ethoxypentaethylene glycol mono(meth)acrylate, ethoxyhexaethylene glycol mono(meth)acrylate,Ethoxyheptaethylene glycol mono(meth)acrylate, ethoxyhexaethylene glycol mono(meth)acrylate, ethoxyoctaethylene glycol mono(meth)acrylate, ethoxynonaethylene glycol mono(meth)acrylate, ethoxydecaethylene glycol mono(meth)acrylate, ethoxytripropylene glycol mono(meth)acrylate, ethoxytetrapropylene glycol mono(meth)acrylate, ethoxypentapropylene glycol mono(meth)acrylate, ethoxyhexapropylene glycol mono(meth)acrylate, ethoxyheptapropylene glycol mono(meth)acrylate, ethoxyhexapropylene glycol mono(meth)acrylate, ethoxyoctapropylene glycol butylene glycol mono(meth)acrylate, ethoxynonapropylene glycol mono(meth)acrylate, ethoxydecapropylene glycol mono(meth)acrylate, ethoxytributylene glycol mono(meth)acrylate, ethoxytetrabutylene glycol mono(meth)acrylate, ethoxypentabtylene glycol mono(meth)acrylate, ethoxyhexabtylene glycol mono(meth)acrylate, ethoxyheptabtylene glycol mono(meth)acrylate, ethoxyhexabtylene glycol mono(meth)acrylate, ethoxyoctabtylene glycol mono(meth)acrylate, ethoxynonabtylene glycol mono(meth)acrylate, ethoxydecabutylene glycol mono(meth)acrylate, and the like. Among these, ethoxydiethylene glycol mono(meth)acrylate, ethoxytriethylene glycol mono(meth)acrylate, ethoxytetraethylene glycol mono(meth)acrylate, ethoxypentaethylene glycol mono(meth)acrylate, ethoxyhexaethylene glycol mono(meth)acrylate, ethoxyheptaethylene glycol mono(meth)acrylate, ethoxyhexaethylene glycol mono(meth)acrylate, ethoxyoctaethylene glycol mono(meth)acrylate, ethoxynonaethylene glycol mono(meth)acrylate, ethoxydecaethylene glycol mono(meth)acrylate, ethoxytripropylene glycol mono(meth)acrylate,Ethoxytetrapropylene glycol mono(meth)acrylate, ethoxypentapropylene glycol mono(meth)acrylate, ethoxyhexapropylene glycol mono(meth)acrylate, ethoxyheptapropylene glycol mono(meth)acrylate, ethoxyhexapropylene glycol mono(meth)acrylate, ethoxyoctapropylene glycol mono(meth)acrylate, ethoxynonapropylene glycol mono(meth)acrylate, ethoxydecapropylene glycol mono(meth)acrylate, ethoxytributylene glycol Cholesterol mono(meth)acrylate, ethoxytetrabutylene glycol mono(meth)acrylate, ethoxypentabtylene glycol mono(meth)acrylate, ethoxyhexabtylene glycol mono(meth)acrylate, ethoxyheptabtylene glycol mono(meth)acrylate, ethoxyhexabtylene glycol mono(meth)acrylate, ethoxyoctabtylene glycol mono(meth)acrylate, ethoxynonabtylene glycol mono(meth)acrylate, and ethoxydecabutylene glycol mono(meth)acrylate are preferred. These can be used alone or in combination of two or more.

[0039] The content of component (C) is not particularly limited, but is preferably in the range of 10 to 80 parts by weight, more preferably 20 to 70 parts by weight, even more preferably 25 to 60 parts by weight, and particularly preferably 30 to 50 parts by weight, per 100 parts by weight of the combined total of components (B) and (C). By keeping the content within the above range, a photocurable composition can be obtained that can more quickly produce a cured product upon photocuring and that exhibits low repulsion over a wide range of compression ratios (compression ranges). The total content of components (B) and (C) is not particularly limited, but is preferably 30 to 90 parts by weight, more preferably 40 to 80 parts by weight, and particularly preferably 50 to 70 parts by weight, per 100 parts by weight of the combined total of the photocurable composition. The monofunctional (meth)acrylate monomer for component (C) may be used alone or in combination of two or more types. When two or more types are used in combination, the content of component (C) refers to the combined amount.

[0040] Component (D) is a photoradical polymerization initiator. Component (D) can be a compound that generates radical species upon irradiation with active energy rays such as visible light, ultraviolet light, or an electron beam. Examples of such photoradical polymerization initiators include acetophenone-based photoradical polymerization initiators, benzoin-based photoradical polymerization initiators, benzophenone-based photoradical polymerization initiators, thioxanthone-based photoradical polymerization initiators, acylphosphine oxide-based photoradical polymerization initiators, and titanocene-based photoradical polymerization initiators. Among these, component (D) is preferably an acetophenone-based photoradical polymerization initiator and / or an acylphosphine oxide-based photoradical polymerization initiator, and more preferably an acetophenone-based photoradical polymerization initiator, because it allows for a photocurable composition that cures quickly even with a small cumulative light dose. These can be used alone or in combination of two or more.

[0041] Examples of acetophenone-based photoradical polymerization initiators include, but are not limited to, diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, benzyl dimethyl ketal, 4-(2-hydroxyethoxy)phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-methyl-2-morpholino(4-thiomethylphenyl)propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)butanone, and 2-hydroxy-2-methyl-1-[4-(1-methylvinyl)phenyl]propanone oligomer. Commercially available acetophenone-based photoradical polymerization initiators include Omnirad (registered trademark, the same applies hereinafter) 184, Omnirad 1173, Omnirad 2959, Omnirad 127 (manufactured by IGM Resins B.V.), and ESACURE (registered trademark) KIP-150 (manufactured by IGM Resins B.V.).

[0042] Examples of acylphosphine oxide-based photoradical polymerization initiators include, but are not limited to, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, etc. Commercially available acylphosphine oxide-based photoradical polymerization initiators include OmniradTPO, Omnirad819, and Omnirad819DW (manufactured by IGM Resins B.V.).

[0043] The content of component (D) is not particularly limited, but is preferably 0.1 to 15 parts by mass, more preferably 0.3 to 7.0 parts by mass, particularly preferably 0.5 to 5.0 parts by mass, and most preferably 1.0 to 3.0 parts by mass, per 100 parts by mass of the combined total of components (B) and (C). By using an amount within the above range, a photocurable composition can be obtained that can produce a cured product with low repulsion over a wider range of compression ratios (compression range). The photoradical polymerization initiator as component (D) may be used alone or in combination of two or more types. When two or more types are used in combination, the content of component (D) refers to the total amount.

[0044] Component (E) is a plasticizer that does not have a reactive group such as a (meth)acryloyl group. In particular, the use of a plasticizer that does not have a (meth)acryloyl group has the effect of reducing the reaction force generated in the resulting cured product over a wide range of compression ratios (compression ranges). By combining component (E) with component (A), a photocurable composition can be obtained that produces a cured product with low reaction force over a wide range of compression ratios (compression ranges).

[0045] The plasticizer as component (E) preferably has a polyether skeleton to improve the desired effect. The definition of "polyether skeleton" is as described in the section on component (B) above. The number of carbon atoms constituting the alkylene oxide is not particularly limited, but the number of carbon atoms in one repeating unit is preferably 2 to 10, more preferably 2 to 5, particularly preferably 2 to 4, and most preferably 3. In other words, the polyether skeleton contained in component (E) is preferably a polypropylene oxide skeleton. The number of repeating units of the alkylene oxide constituting the polyether skeleton is not particularly limited, but is, for example, 3 to 300, more preferably 5 to 100, particularly preferably 10 to 60, and most preferably 20 to 50.

[0046] The number average molecular weight of component (E) is not particularly limited, but is, for example, 200 to 30,000, preferably 350 to 10,000, particularly preferably 500 to 5,000, and most preferably 1,000 to 3,000. Unless otherwise specified, the number average molecular weight used herein is a value calculated using size exclusion chromatography (SEC) in terms of standard polystyrene. By keeping the number average molecular weight within the above range, a photocurable composition can be obtained that can more quickly produce a cured product upon photocuring and that exhibits low repulsion over a wide range of compression ratios (compression range).

[0047] Examples of plasticizers that can be used as component (E) include polyols and condensates thereof, such as glycerin, diglycerin, triglycerin, ethylene glycol, propylene glycol, and polyethylene glycol.

[0048] The plasticizer used as component (E) may be either a synthetic product or a commercially available product. Examples of commercially available products for component (E) include, but are not limited to, PEG#300, PEG#400, PEG#600, PEG#1000, PEG#1500, PEG#15400, PEG#2000, PEG#4000, PEG#6000, PEG#1100, PEG#2000, and Uniol® D-700, D-1000, D1200, D2000, D4000, PB-500, PB-700, PB-1000, and PB-2000 (manufactured by NOF Corporation).

[0049] The content of component (E) is not particularly limited, but is preferably 20 to 200 parts by mass, more preferably 25 to 150 parts by mass, particularly preferably 30 to 100 parts by mass, and most preferably 35 to 70 parts by mass, per 100 parts by mass of the combined total of components (B) and (C). By using an amount within the above range, a photocurable composition can be obtained that can more quickly produce a cured product upon photocuring and that exhibits low repulsion over a wide range of compression ratios (compression ranges). The plasticizer used as component (E) may be a single type, or two or more types may be used in combination. When two or more types are used in combination, the content of component (E) refers to the total amount.

[0050] Component (F) is a polyfunctional (meth)acrylic monomer having two or more functional (meth)acryloyl groups in one molecule, excluding component (B). By combining component (F) with component (A), a photocurable composition can be obtained that rapidly cures upon photocuring and exhibits low repulsion over a wide range of compression ratios (compression ranges). Here, the polyfunctional (meth)acrylic monomer is a compound having two or more (meth)acryloyl groups. The (meth)acryloyl groups may be contained in the monomer in the form of (meth)acryloyloxy groups.

[0051] The number of (meth)acryloyl groups contained in the polyfunctional (meth)acrylic monomer as component (F) is not particularly limited as long as it is two or more, but since a photocurable composition with a fast curing rate can be obtained even with a small cumulative light dose, it is preferably three or more (trifunctional or more), more preferably four or more (tetrafunctional or more), and particularly preferably five or more (pentafunctional or more). Meanwhile, the upper limit of the number of (meth)acryloyl groups is not particularly limited, but is, for example, eight or less (octafunctional or less). Furthermore, for the purposes of improving photocurability and reducing the compression set of the resulting cured product, it is preferable that the (meth)acryloyl groups contained in component (F) are acryloyl groups.

[0052] In order to improve the desired effects, the polyfunctional (meth)acrylic monomer as component (F) is preferably a polyfunctional (meth)acrylate monomer (i.e., an ester compound having two or more (meth)acryloyloxy groups, or a (meth)acrylic acid ester). The preferred number of (meth)acryloyl groups contained in the polyfunctional (meth)acrylate monomer is the same as above.

[0053] The molecular weight of component (F) is not particularly limited, but from the viewpoint of improving the curability of the photocurable composition, it is preferably less than 1000, and more preferably not more than 600. Furthermore, from the viewpoint of excellent compatibility with component (A), the molecular weight of the compound of component (F) is preferably more than 200, and more preferably 300 or more.

[0054] On the other hand, from the viewpoint of photocurability, the component (F) is preferably a polyfunctional (meth)acrylic monomer having no hydroxyl groups, more preferably a polyfunctional (meth)acrylate monomer having no hydroxyl groups, and particularly preferably a polyfunctional acrylate monomer having no hydroxyl groups.

[0055] The component (F) is not particularly limited, but examples thereof include tetrafunctional (meth)acrylate monomers such as ditrimethylolpropane tetra(meth)acrylate and pentaerythritol tetra(meth)acrylate; pentafunctional (meth)acrylate monomers such as alkyl-modified dipentaerythritol penta(meth)acrylate; and hexafunctional (meth)acrylate monomers such as dipentaerythritol hexa(meth)acrylate. Of these, alkyl-modified dipentaerythritol penta(meth)acrylate and dipentaerythritol hexa(meth)acrylate are preferred. These monomers can be used alone or in combination of two or more.

[0056] The content of component (F) is not particularly limited, but is preferably in the range of 0.1 to 15 parts by mass, more preferably 0.2 to 5 parts by mass, and particularly preferably 0.3 to 3 parts by mass, per 100 parts by mass of the combined total of components (B) and (C). By using an amount within the above range, a photocurable composition can be obtained that can more quickly produce a cured product upon photocuring and that exhibits low repulsion over a wide range of compression ratios (compression ranges). The polyfunctional (meth)acrylic monomer as component (F) may be used alone, or two or more types may be used in combination. When two or more types are used in combination, the content of component (F) refers to the total amount.

[0057] Component (G) is an inorganic filler, excluding component (A). Component (G) is not particularly limited, but examples include glass powder, fumed silica powder, alumina powder, talc powder, mica powder, ceramic powder, silicone rubber powder, calcium carbonate powder, aluminum hydroxide powder, aluminum nitride powder, carbon powder, kaolin clay powder, dried clay mineral powder, and dried diatomaceous earth powder. Of these, fumed silica powder and talc powder are preferred for the purpose of obtaining a photocurable composition that will yield a cured product with low repulsion over a wide range of compression ratios (compression ranges). These can be used alone or in combination of two or more. Component (G) does not include those used for the surface treatment of component (A).

[0058] For the purpose of obtaining a photocurable composition that can produce a cured product with low repulsion over a wide range of compression ratios (compression range), the fumed silica powder is preferably hydrophobized with at least one surface treatment agent selected from the group consisting of organochlorosilanes, dimethylsilicones, and hexamethyldisilazanes. Specific examples of silica include Aerosil (registered trademark) R974, R972, R972V, R972CF, R805, R812, R812S, R816, R8200, RY200, RX200, RY200S, and R202 (manufactured by Nippon Aerosil). These can be used alone or in combination of two or more.

[0059] The content of component (G) is not particularly limited, but is preferably in the range of 0.01 to 100 parts by mass, more preferably 0.1 to 50 parts by mass, particularly preferably 0.5 to 20 parts by mass, and particularly preferably 3 to 10 parts by mass, per 100 parts by mass of the combined total of components (B) and (C). By using an amount within the above range, a photocurable composition can be obtained that will give a cured product with low repulsion over an even wider range of compression ratios (compression range). The inorganic filler as component (G) may be used alone, or two or more types may be used in combination. When two or more types are used in combination, the content of component (G) refers to the total amount.

[0060] <Optional ingredients> The composition may further contain additives such as a thermoplastic resin (excluding component (A)), elastomer, tackifier, surfactant, organic peroxide, polythiol, silane coupling agent, storage stabilizer, antioxidant, light stabilizer, rust inhibitor, pigment, dye, and flame retardant, as long as the object of the present invention is not impaired.

[0061] The specific gravity of the photocurable composition containing components (A) to (G) is preferably less than 1.00, which provides a shock-absorbing performance with a repulsive force of 1 to 300 kPa when compressed by 10% and a repulsive force of 1 to 500 kPa when compressed by 50%.

[0062] <Curing method> The photocurable composition according to the present invention can be cured by irradiation with active energy rays such as ultraviolet light or visible light. The term "active energy rays" as used herein refers to light in a broad sense, including various active energy rays such as radioactive rays such as α-rays and β-rays, electromagnetic waves such as γ-rays and X-rays, electron beams (EB), ultraviolet rays with a wavelength of about 100 to 400 nm, and visible light with a wavelength of about 400 to 800 nm.

[0063] The light source used to cure the photocurable composition is not particularly limited, and examples thereof include low-pressure mercury lamps, medium-pressure mercury lamps, high-pressure mercury lamps, ultra-high-pressure mercury lamps, black light lamps, microwave-excited mercury lamps, metal halide lamps, sodium lamps, halogen lamps, xenon lamps, LEDs, fluorescent lamps, sunlight, and electron beam irradiators. Specific examples of irradiators include, but are not limited to, belt conveyor irradiators and spot irradiators. The lower limit of the cumulative light dose is not particularly limited, but is preferably 0.5 kJ / m or more, and more preferably 1.0 kJ / m or more. As described above, the photocurable composition according to the present invention can be sufficiently cured even with a small cumulative light dose, and the resulting cured product has excellent properties. The upper limit of the cumulative light dose is also not particularly limited, but is preferably 50 kJ / m or less, and more preferably 30 kJ / m or less.

[0064] (Compression pump) The pressure pump 100 is configured to be able to pump a viscous material, and includes a tank 10, a piston 20, and an air cylinder 30.

[0065] As shown in FIG. 1, the tank 10 has a storage space 11 for storing the viscous material. The tank 10 is a cylindrical member made of plastic or metal, such as polyethylene, polypropylene, ethylene vinyl acetate copolymer, polyethylene terephthalate, or polyamide, and has an open top so that the viscous material can be stored. However, the specific shape of the tank 10 is not limited to a cylinder as long as it can store the viscous material, and it may also be configured as a polygonal prism, such as a square prism, in addition to the above. Furthermore, the shape of the tank 10 does not have to be a cylinder or polygonal prism as long as it can be stably installed on the ground.

[0066] The piston 20 is slidably inserted into the tank 10. The piston 20 includes a main body 21, a pressing surface 22, a suction passage 23, and an outer peripheral portion 24, as shown in FIG.

[0067] The main body 21 is formed in a substantially cylindrical shape, has a suction passage 23 formed in the approximate center, and has a pressing surface 22 formed below it. The main body 21 can be made of, for example, a metal plate.

[0068] The pressing surface 22 is provided on the lower part of the main body 21 and configured as a portion for pressing the viscous material. In this embodiment, the pressing surface 22 is formed in a substantially circular plate shape, but the specific shape is not limited to a circular plate as long as it can press the viscous material.

[0069] The suction passage 23 is configured as a portion through which the viscous material in the tank 10 flows by the pressure of the pressing surface 22. The suction passage 23 is a substantially cylindrical cavity provided inside the main body 21, but the specific shape does not have to be cylindrical as long as the viscous material can flow through it.

[0070] The outer peripheral portion 24 is provided on the outer periphery of the main body portion 21. A groove for attaching a sealing member such as rubber can be provided in the outer peripheral portion 24. This can prevent the viscous material from leaking out from the outer periphery of the piston 20 when the viscous material is being pressed by the piston 20.

[0071] The air cylinder 30 is provided to use air pressure to move the piston 20 up and down between the opening and bottom of the tank 10. The air cylinder 30 causes the viscous material in the tank 10 to flow inside the piston 20. The pressure pump 100 causes the viscous material to flow through the pipe P to the leveling section 200. The viscous material flows through the pipe P at a pressure of 1.0 to 2.0 MPa.

[0072] (Leveling Department) The leveling unit 200 is configured to level the flow rate of the viscous material delivered by the pressure pump 100, and includes a storage unit 210, a shaft 220, and a pushing unit 230, as shown in FIG. 2. The storage unit 210 is configured to form a semi-closed space connectable to a flow path, with an inlet 211 connected to a pipe P and an outlet 212 connected to the dispenser 300 via a pipe (not shown). The storage unit 210 is configured to rotatably accommodate the shaft 220 and the pushing unit 230. When installed, the storage unit 210 forms a vertically long storage space. The shaft 220 is installed to extend vertically in the internal space of the storage unit 210, and is configured to be rotatable integrally with the pushing unit 230.

[0073] The pushing unit 230 is configured to push the piston with the force of a spring so that the flow rate of the viscous material flowing in from the inlet 211 is sufficient and the flow rate of the viscous material flowing out from the outlet 212 is backed up. In this embodiment, the pushing unit 230 is configured to include a helical spring. The leveling unit 200 is known under the trade name "wave absorber."

[0074] (Dispenser) Dispenser 300 is provided downstream of leveling unit 200 and is configured to deliver the viscous material leveled by leveling unit 200. Dispenser 300 has the structure of a rotary positive displacement uniaxial eccentric screw pump such as the Mohno Dispenser (registered trademark), and its main components are configured by a combination of a rotor equivalent to a male screw and a stator equivalent to a female screw. When the rotor is inserted into the stator of the dispenser, a gap called a cavity is formed between the stator and rotor, and when the rotor rotates within the stator, the cavity moves toward the discharge side while generating a suction force.

[0075] As the rotor rotates, the fluid sucked into the cavity is continuously transported to the discharge side in each sealed space and discharged to the outside. Since the cross-sectional area of ​​the cavity is constant regardless of the rotor position, the amount of fluid discharged is constant. This allows the amount of fluid discharged per unit time to be proportional to the rotor speed, making it possible to transfer a fixed amount of fluid without pulsation. In addition, by reversing the direction of rotation of the rotor, the flow of fluid can be reversed and it is possible to switch between discharge and suction.

[0076] (application valve) The application valve 400 is configured to apply the viscous material dispensed from the dispenser 300 in a planar manner, and as shown in Figure 3, it includes a flow path 410, a buffer chamber 420, a passage 430, a buffer chamber 440, an opening / closing valve 450, and a slit nozzle 460.

[0077] The flow path 410 is formed so that the dimension of the cross section perpendicular to the flow path is sufficiently large compared to the passage 430 described later. The dimension of the perpendicular cross section of the flow path 410 is not particularly limited, but is, for example, on the order of several tens of mm.

[0078] The buffer chamber 420 is provided at the end of the flow path 410 and is configured to be longer in width than the passage 430 and longer in depth than the passage 430 .

[0079] The passage 430 is configured to extend along the height direction so as to intersect with the direction in which the flow path 410 extends. The passage 430 is configured to have smaller dimensions in the width direction and depth direction than the flow path 410 and the buffer chamber 420 as described above, so that it generates a sufficiently large fluid resistance against the flow velocity of the viscous material.

[0080] The buffer chamber 440 is provided downstream of the passage 430, and is configured so that its width and depth dimensions are larger than those of the passage 430. The buffer chamber 440 is configured to accommodate an open / close valve 450 inside.

[0081] The on-off valve 450 is configured to be rotatable by a motor or the like in the internal space of the buffer chamber 440. A linear passage 451 is formed in the on-off valve 450, and the passage 430 and the slit nozzle 460 are configured to be connected or disconnected depending on the rotation of the on-off valve 450. This allows the viscous material from the dispenser 300 to flow through the slit nozzle 460 or not to flow through it.

[0082] The slit nozzle 460 discharges the viscous material flowing from the flow path 410 so as to stretch it in the width direction.

[0083] The viscous material from pressure pump 100 has its flow rate leveled in leveling section 200, and is then passed through dispenser 300 with almost no pulsation before being circulated to application valve 400. In application valve 400, the viscous material is filled in buffer chamber 420, then passes through passage 430 and is filled into buffer chamber 440, and after the pressure is equalized, is discharged from slit nozzle 460 evenly throughout the nozzle.

[0084] As described above, in this embodiment, the application system 1 includes the pressure pump 100 capable of pumping a viscous material, the leveling unit 200, the dispenser 300, and the application valve 400. The leveling unit 200 is configured to level the flow rate of the viscous material delivered by the pressure pump 100. The dispenser 300 delivers the viscous material leveled by the leveling unit 200 and has a rotary positive displacement uniaxial eccentric screw pump structure. The application valve 400 is configured to apply the viscous material delivered from the dispenser 300 in a planar manner. This configuration prevents the (cushion-absorbing) function of the resin cushioning material b2 used in the automobile battery pack B from being impaired.

[0085] The viscous material is configured to contain resin and hollow filler. By discharging such a viscous material through the application system 1, the (buffering) function of the resin used in the battery pack B as the buffer material b2 can be prevented from being impaired.

[0086] Furthermore, a pipe P capable of circulating the viscous material is provided from the pressure pump 100 to the leveling unit 200, and the pipe P is configured to circulate the viscous material at a pressure of 1.0 to 2.0 MPa. This configuration prevents the specific gravity of the resin from increasing, and prevents or suppresses the loss of the (cushioning) function of the cushioning material b2.

[0087] The specific gravity of the viscous material is set to be less than 1.00, which can prevent or suppress the loss of the (buffering) function of the resin as the buffer material b2.

[0088] The present invention is not limited to the above-described embodiment, and various modifications are possible within the scope of the claims. In the above, two pressure-feed pumps 100 are provided in the coating system, but the number of pressure-feed pumps may be other than two. [Explanation of symbols]

[0089] 1 application system, 100 pressure pump, 200 Leveling Department, 300 dispensers, 400 dispensing valve, B Battery pack, b2 Buffer material.

Claims

1. a pump capable of pumping a viscous material; a leveling unit that levels the flow rate of the viscous material delivered by the pressure delivery pump; a dispenser that delivers the viscous material leveled by the leveling unit and has a rotary positive displacement uniaxial eccentric screw pump structure; and a coating valve that coats the viscous material dispensed from the dispenser onto a surface.

2. The application system of claim 1 , wherein the viscous material includes a resin and a hollow filler.

3. a pipe through which the viscous material can flow from the pressure pump to the leveling unit; 3. The coating system according to claim 1, wherein the viscous material flows through the pipe at a pressure of 1.0 to 2.0 MPa.

4. The application system of claim 1 , wherein the viscous material has a specific gravity of less than 1.

00.

5. A buffer material disposed between adjacent cells constituting a battery pack, the buffer material comprising a viscous material applied by the application system according to claim 1.

6. A battery pack in which a buffer material containing the viscous material formed by the application system of claim 1 is disposed between adjacent cells.

Images