JP2006324056A - Insulating material and battery case using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an insulating material with superior corrosion resistance against the highly corrosive battery content materials, and a battery case using this insulating material. <P>SOLUTION: The insulating material for electrode attachment is used for a battery case made of the polyethylene terephthalate resin. In the battery case, a polyester resin coating aluminum plate-formed lid material is attached to an opening of a can body by the double winding fixing method, and the insulating material made of the polyethylene terephthalate resin for electrode attachment is fitted to a pierced hole provided by drilling the center of the lid material through the use of an adhesive made by blending the materials (A) with (B). In the material (A), the polyester resin comprises dicarboxylic acid component containing terephthalic acid as a main component, and glycol component with the glass transition temperature ranging from 30 to 110°C. In the material (B), the curing agent consists of at least one kind of resin among phenol resin, amino resin and polyisocyanate resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an insulator excellent in electrolytic solution corrosion resistance and a battery container using the same. The present invention relates to a battery container.

As shown in Patent Document 1 and Patent Document 2, a battery container used for a battery, an electrolytic capacitor, or the like is formed by punching a metal plate such as an aluminum plate into a disc-like blank, and by using a processing method such as draw forming, Furthermore, a canopy is stacked on the opening of the upper portion of the can body portion and wound and sealed. And in order to take out an electrode out of a battery container, the insulator which consists of a synthetic resin etc. which electrically insulates is provided.
Such insulators are often made of urethane rubber, polypropylene resin, or the like that is molded in accordance with the shape of the through-hole, and are attached to a metal plate such as an aluminum plate by an adhesive. .
In addition, an electrolytic solution mainly composed of highly corrosive propylene carbonate salt is encapsulated as the battery contents. For such highly corrosive contents, the urethane rubber or polypropylene resin is used. The formed insulator has insufficient corrosion resistance, and the leakage of the content liquid was often observed.
In addition, a polyester resin-coated aluminum plate has been used as a container material having excellent corrosion resistance.
However, the polyester resin film coated on the surface of the lid member to which the insulator is attached has a problem that the adhesiveness with the insulator is not sufficient.
Japanese Patent No. 3427216 JP 2002-343310 A

The present invention has been made in view of the above-described problems, and an object thereof is to provide an insulator having excellent corrosion resistance against highly corrosive battery contents.
Another object of the present invention is to provide a battery container in which an insulator is firmly attached to a lid member using an adhesive having excellent adhesion to the insulator even when a polyester resin-coated aluminum plate is used as a container material. And

The insulator according to claim 1 of the present invention is an insulator for attaching an electrode used for a battery container, and is made of polyethylene terephthalate resin.
The battery container according to claim 2 of the present invention is a battery container in which a lid member formed with a polyester resin-coated aluminum plate is attached to an opening of a can body part by double wrapping the lid. An insulator made of polyethylene terephthalate resin for electrode attachment is provided in the through hole provided by drilling the central part of the member, with an adhesive formed by blending the following (A) resin and (B) curing agent. It is attached.
(A) A polyester resin comprising a dicarboxylic acid component mainly composed of terephthalic acid and a glycol component, and having a glass transition temperature in the range of 30 to 110 ° C. (B) consisting of at least one of a phenol resin, an amino resin, and a polyisocyanate resin. Curing agent The battery container according to claim 3 is a battery container in which a lid member formed with a polyester resin-coated aluminum plate is double-tightened and attached to an opening of a can body portion, and the lid member An insulator made of polyethylene terephthalate resin for electrode attachment is attached to a through hole provided by perforating the central portion of the electrode through an adhesive comprising the following (A) resin and (B) curing agent. It is characterized by being.
(A) It consists of a dicarboxylic acid component of 80-100 mol% terephthalic acid and a glycol component, has a glass transition temperature in the range of 30 to 110 ° C., and consists of a polyester resin (B) polyisocyanate resin having a number average molecular weight of 8000 to 30000. Curing Agent The battery container according to claim 4 is characterized in that, in claim 2 or 3, the adhesive has a weight ratio of (A) :( B) in the range of 90:10 to 99: 1. And

Since the insulator of the present invention is made of polyethylene terephthalate resin, it has excellent corrosion resistance against electrolytes mainly composed of highly corrosive propylene carbonate salt as the battery contents, and leakage resistance of the contents Improves.
The battery container according to the present invention uses an insulator made of polyethylene terephthalate resin and bonds the insulator to a lid member made of a polyester resin-coated aluminum plate using an adhesive having a specific composition. It can be firmly bonded to the through-hole and has excellent leakage resistance of the battery contents.

FIG. 1 is a perspective view showing an exploded configuration diagram of a battery container according to the present invention. In FIG. 1, a lid member 1 formed of a polyester resin-coated aluminum plate is attached to an opening flange 2f of a can body 2 by double-tightening a flange 2f. A through-hole 3 is provided in the center of the lid member 1 and an insulator 4 made of polyethylene terephthalate resin for attaching the electrode 5a is attached via an adhesive.
FIG. 1 shows an embodiment in which openings are provided at both ends of the can body 2, and an example in which an electrode 5 b and an insulator 4 are also provided in the lower lid.

(Cover member used for battery container)
First, the lid member of the battery container to which the insulator of the present invention is attached will be described. The lid member is composed of an aluminum plate, a surface treatment layer, and a resin film as a base material.

(Aluminum plate)
Examples of the aluminum plate that serves as a base material for the lid member include various aluminum materials such as alloys in the 3000s, 5000s, and 6000s described in JIS 4000. Among them, those in the 3000s are preferably used.
The thickness of the aluminum plate is generally preferably in the range of 0.1 to 1.0 mm from the viewpoint of strength and formability.

(Surface treatment layer)
The aluminum plate is preferably subjected to a surface treatment on the surface in order to improve processing adhesion to the coating resin. As such surface treatment, an aluminum plate can be cold-rolled, and chromium phosphate treatment or other organic / inorganic surface treatment can be performed by dipping or spraying. A coating type surface treatment can also be used.
When a treatment film is formed on the aluminum plate by chromic acid phosphate treatment, from the viewpoint of processing adhesion of the resin film to be laminated, the chromium content is preferably 5 to 40 mg / m ² as total chromium, and 15 to 30 mg / m. A range of ² is more preferred.

When surface treatment such as chromium phosphate treatment is not performed, adhesion after processing of the resin film is lowered, and peeling may occur after molding and washing. Even when the amount of the total chromium containing the metal and the oxide is less than 5 mg / m ² , the processing adhesion of the resin film is lowered, and peeling may occur, which is not preferable. Moreover, when the amount of total chromium exceeds 40 mg / m < ² >, it is unpreferable from an economical viewpoint, the viewpoint of the adhesive fall by cohesive failure generation, etc.
On the other hand, when the chromic acid phosphate treatment is performed on the side where the resin film is not laminated, the total chromium amount is 8 mg / m ² or less.
If the total amount of chromium on the outer surface exceeds 8 mg / m ² , color unevenness occurs or the metallic luster color tone is lost. This is because the metallic luster is important as the appearance color of the can.

As an example of the formation method of the surface treatment layer 11, the formation of the chromic acid chromic acid treatment film is performed by means known per se, for example, an aluminum plate is degreased with caustic soda and slightly etched, and then CrO ₃ : 4 g / L, H ₃ PO ₄ : 12 g / L, F: 0.65 g / L, and the rest is performed by chemical treatment immersed in a treatment solution such as water.

(Laminated resin film)
In the lid member of the present invention, a resin film is formed on a surface-treated aluminum plate. Examples of the resin film include a polyester film. As the polyester film, a copolymer polyethylene terephthalate biaxially stretched film having a melting point of 210 to 252 ° C. mainly composed of ethylene terephthalate units and containing a small amount of other ester units is suitable. is there. This resin film is obtained by forming a copolymer polyester mainly composed of ethylene terephthalate units into a film by a T-die method or an inflation film forming method, and sequentially or simultaneously biaxially stretching the film at a stretching temperature. The film is manufactured by heat setting and then laminated to an aluminum plate.
The polyethylene terephthalate film suitably used as the polyester film of the present invention is 70 mol% or more of the dibasic acid component in the copolyester, particularly 75 mol% or more is composed of the terephthalic acid component, and 70 mol% or more of the diol component, Particularly, 75 mol% or more is composed of ethylene glycol, and 1 to 30 mol%, particularly 5 to 25 mol% of the dibasic acid component and / or diol component is a dibasic acid component other than terephthalic acid and / or a diol other than ethylene glycol. It preferably consists of components.
Dibasic acids other than terephthalic acid include aromatic dicarboxylic acids such as isophthalic acid, phthalic acid, and naphthalenedicarboxylic acid: alicyclic dicarboxylic acids such as siloxane hexanedicarboxylic acid; succinic acid, adipic acid, sebacic acid, dodecanedioic acid Aliphatic dicarboxylic acids such as: one or a combination of two or more thereof, and diol components other than ethylene glycol include propylene glycol, 1,4-butanediol, diethylene glycol, 1,6-hexylene glycol, cyclohexane 1 type, or 2 or more types, such as dimethanol and the ethylene oxide adduct of bisphenol A, are mentioned.
The combination of these comonomers must be such that the melting point of the copolyester is within the above range.
The copolyester used should have a molecular weight sufficient to form a film, for which purpose an intrinsic viscosity (IV) of 0.55 to 1.9 dl / g, in particular 0.65 to 1.4 dl / g. Those in the range of g are desirable.
It is important that the copolyester film is biaxially stretched. The degree of biaxial stretching can also be confirmed by polarized fluorescence method, birefringence method, density gradient tube method density and the like.

(Film thickness)
The thickness of the polyester film is desirably 8 to 50 μm, particularly 12 to 40 μm, in view of the balance between the barrier property of the corrosive component and workability. For this biaxially stretched polyester film, a film compounding agent known per se, for example, an anti-blocking agent such as amorphous silica, a pigment such as carbon black (black), various antistatic agents, a lubricant, etc., according to a known formulation. Can be blended.

(laminate)
In laminating, the time for the film to be laminated to pass through the crystallization temperature range is made as short as possible, and preferably this temperature range is passed within 10 seconds, particularly within 5 seconds. Therefore, only the aluminum material is heated at the time of lamination, and the resin-coated aluminum plate is forcibly cooled immediately after the film lamination. For cooling, direct contact with cold air or cold water or pressure contact of a cooled cooling roller is used. When the film is laminated, the degree of crystal orientation can be relaxed by heating the film to a temperature close to the melting point and performing rapid cooling after lamination.

(Adhesion primer)
An adhesive primer can be interposed between the polyester film and the aluminum plate, but those exhibiting excellent adhesion to both the aluminum plate and the film are preferred.
A typical primer excellent in adhesion and corrosion resistance is a phenol-epoxy primer comprising a resol type phenol aldehyde resin derived from various phenols and formaldehyde, and a bisphenol type epoxy resin. A primer containing a resin and an epoxy resin in a weight ratio of 50:50 to 5:95, particularly 40:60 to 10:90. In general, the adhesive primer layer is preferably provided in a thickness of 0.3 to 5 μm.

(Manufacture of resin-coated aluminum plate)
Hereinafter, a method for producing a resin-coated aluminum plate will be described. The resin film is laminated on the aluminum plate by laminating the biaxially stretched polyester film and the aluminum plate under the condition that only the surface layer portion in contact with the aluminum plate of the film is melted. For example, the aluminum plate is preheated to a temperature equal to or higher than the melting point of the biaxially stretched polyester film, and the resin-coated aluminum plate is rapidly cooled immediately after lamination.
Further, the biaxially stretched polyester film and the aluminum plate can be laminated by pressure bonding through an adhesive primer layer provided on any of them.

(Manufacture of lid members)
The lid member is manufactured as follows. First, a resin-coated aluminum plate is punched into a rectangular plate by pressing to form a desired lid shape, and a concave portion and a through hole are formed in the central portion using a mold to form a lid member.

(Insulator)
FIG. 2 shows a plan view of the insulator of the present invention (FIG. 2 (a)) and an AA sectional view (FIG. 2 (b)). The insulator 4 of the present invention includes a ring 4a having a donut shape, a cavity portion 4b penetrating in the thickness direction for mounting the electrode 5a, and an annular recess 4c for fitting the inner edge of the through hole 3 provided in the lid member. Have In the present embodiment, the annular recess 4c is provided along the inner diameter at a substantially central portion in the thickness direction of the inner diameter portion of the ring 4a, and has a structure in which a groove is formed in the outer diameter direction of the ring 4a.

The insulator of the present invention is made of polyethylene terephthalate resin. The reason is that the result that the corrosion resistance with respect to the electrolyte etc. which have as a main component the highly corrosive propylene carbonate salt enclosed as the battery content was excellent was obtained. Table 1 shows the results of investigating the corrosion resistance of the insulator of the present invention.
In addition, as the material of the insulator, polybutylene terephthalate resin can be used alone or in combination with polyethylene terephthalate resin.

（プロピレンカーボネート塩を主成分とする電解液に対する耐腐食性の評価）

なお、８００時間浸漬の結果も５００時間での評価と同様であった。
本発明の絶縁体厚みは、蓋部材素材の厚みよりも厚ければ、特に規定するものではないが、０．３〜３．０ｍｍのものが好適である。リング４ａの外径や内径も蓋部材の大きさや電極のサイズなどにより決定されるので、本発明において特に規定するものではない。

(Evaluation of corrosion resistance against electrolytes based on propylene carbonate salt)

In addition, the result of 800-hour immersion was the same as the evaluation in 500 hours.
The thickness of the insulator of the present invention is not particularly limited as long as it is thicker than the thickness of the cover member material, but a thickness of 0.3 to 3.0 mm is suitable. Since the outer diameter and inner diameter of the ring 4a are also determined by the size of the lid member, the size of the electrode, etc., they are not particularly defined in the present invention.

(Insulator manufacturing method)
A lid member in which a through hole has been formed in advance is mounted in a mold, and a melted polyethylene terephthalate resin is molded into the through hole formed in the lid member by an insert injection method and is mounted so as to be integrated with the lid member. .

(adhesive)
In the present invention, by applying an adhesive composed of at least one curing agent of the following (A) polyester resin + (B) phenol resin, amino resin, polyisocyanate resin to at least one surface of the lid member in advance, Adhesiveness between the lid member having the polyester resin on the surface and the insulator is improved.
(A) Polyester resin In the adhesive used in the present invention, as the polyester resin, the dicarboxylic acid component is composed of 80 to 100 mol% of terephthalic acid and 20 to 0 mol% of dicarboxylic acid other than terephthalic acid, and propylene glycol 60 as the glycol component. It is important to use a polyester resin having a number average molecular weight of 8000 to 30000 consisting of ˜90 mol% and 40 to 10 mol% of glycol other than propylene glycol.
In the dicarboxylic acid component, if the amount of terephthalic acid is less than the above range, adhesive properties such as flexibility and whitening resistance are lowered.
Moreover, when there is less propylene glycol as a glycol component than the said range, solvent-resistant solubility will fall, and when more than the said range, adhesive characteristics, such as workability, will fall.
Examples of carboxylic acid components other than the terephthalic acid component include isophthalic acid, naphthalenedicarboxylic acid, p-β-oxyethoxybenzoic acid, biphenyl-4,4′-dicarboxylic acid, diphenoxyethane-4,4′-dicarboxylic acid, 5 -Sodium sulfoisophthalic acid, hexahydroterephthalic acid, adipic acid, sebacic acid, trimellitic acid, pyromellitic acid, etc. can be mentioned, but it is more elution resistant to use aromatic dicarboxylic acid than aliphatic carboxylic acid It is preferable from the point.

  On the other hand, as alcohol components other than propylene glycol, 1,4-butanediol, ethylene glycol, neopentyl alcohol, 1,6-hexylene glycol, diethylene glycol, triethylene glycol, cyclohexane dimethanol, ethylene oxide adduct of bisphenol A And alcohol components such as glycerol, trimethylolpropane, pentaerythritol, dipentaerythritol and sorbitan.

The polyester resin preferably has a glass transition point (Tg) of 30 ° C. or higher, particularly 50 to 110 ° C. If the glass transition point (Tg) is lower than the above range, the heat-and-moisture resistance may be lowered, and the barrier property against corrosive components may be lowered.
As described above, the number average molecular weight is preferably 8000 to 30,000, particularly preferably 10,000 to 20,000.
If the number average molecular weight is smaller than the above range, the adhesiveness, moist heat resistance, processability and the like are reduced as compared with the case where the number average molecular weight is within the above range. Compared with the case where it exists, adhesive viscosity becomes remarkably high and it becomes inferior to workability. The polyester resin is produced by an ordinary method for producing a high molecular weight polyester by an ester curing method or a direct esterification method.

(B) Curing agent (curing agent used for adhesive)
The phenol resin used as the curing agent is a resin derived from phenol and formaldehyde or a functional derivative thereof, but in the present invention, phenols mainly composed of carboxylic acid and / or metacresol as phenols, particularly resol type. It is particularly preferable to use the phenol resin. Although it does not specifically limit as phenols other than a carboxylic acid and metacresol, Monocyclic monohydric phenols can be used suitably, For example, 3, such as m-ethylphenol, 3, 5- xylenol, m-methoxyphenol, etc. Functional phenols: o-cresol, p-cresol, p-tertbutylphenol, p-ethylphenol, 2,3-xylenol, 2,5-xylenol, p-tert-amylphenol, p-nonylphenol, p-phenylphenol And bifunctional phenols such as p-cyclohexylphenol; monofunctional phenols such as 2,4-xylenol and 2,6-xylenol.
Examples of the amino resin used as the curing agent include a benzoguanamine resin and a melamine resin. These may be used alone, or may be used by blending a benzoguanamine resin and a melamine resin. The amino resin has a basic nitrogen atom concentration of 5 to 20 gram atom, particularly 8 to 17 gram atom per 100 gram of resin, and a concentration of methylol group and etherified methylol group of 0.5 to 1.9 mmol. Particularly preferred are those in the range of 0.7 to 1.7 mmol.
The following polyisocyanates can be used as the polyisocyanate resin curing agent. Examples of polyisocyanates that can be used include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylene-1,4-diisocyanate, xylene-1,3-diisocyanate, 4,4′-diphenylmethane diisocyanate, 2 , 4′-diphenylmethane diisocyanate, 4,4′-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4′-diisocyanate, 2,2′-diphenylpropane-4,4′-diisocyanate, 3,3′-dimethyldiphenylmethane 4,4′-diisocyanate, 4,4′-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4 diisocyanate, naphthylene-1,5-diisocyanate, 3,3′-diisocyanate Aromatic diisocyanates such as methoxydiphenyl-4,4′-diisocyanate, aromatic polyisocyanates such as polyphenylene, polymethylene polyisocyanate, crude tolylene diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (HDI), decamethylene diisocyanate, lysine diisocyanate Aliphatic diisocyanates such as isophorone diisocyanate (IPDI), hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, hydrogenated diphenylmethane diisocyanate, diisocyanates such as alicyclic diisocyanates such as tetramethylxylene diisocyanate, and biuret bodies of the isocyanate, uretdione Modified product, carbodiimide modified product, isocyanurate Examples include modified products, uretonimine modified products, adducts with polyols, and mixed modified products thereof.

Moreover, it can also use in the form of urethane precursors, such as a prepolymer which consists of said polyisocyanate, and active hydrogen-containing compounds, such as a polyol and a polyamine, a modified body, a derivative | guide_body, a mixture.
Suitable curing agents are aliphatic and / or alicyclic isocyanates, and in particular, trimers (isocyanurate forms) of hexamethylene diisocyanate (HDI) and isophorone diisocyanate (IPDI) can be suitably used.

  In the present invention, it is preferable to block the terminal NCO group of the isocyanate curing agent component. Blocking agents include phenolic compounds such as phenol, cresol, ethylphenol, butylphenol, 2-hydroxypyridine, butyl cellosolve, propylene glycol monomethyl ether, benzyl alcohol, methanol, ethanol, n-butanol, isobutanol, 2-ethylhexanol, etc. Alcohol compounds, dimethyl malonate, diethyl malonate, methyl acetoacetate, ethyl acetoacetate, ethyl acetylaceton and other active methylene compounds, mercaptan compounds such as butyl mercaptan and dodecyl mercaptan, acid amides such as acetanilide and acetate amide Compounds, lactam compounds such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, imidazoles such as imidazole and 2-methylimidazole Compounds, urea compounds such as urea, thiourea, ethylene urea, formamide oxime, acetaldoxime, acetone oxime, oxime compounds such as methyl ethyl ketoxime, methyl isobutyl ketoxime, cyclohexanone oxime, diphenylaniline, aniline, carbazole, ethylene Examples include amine compounds such as imine and polyethyleneimine. These can be used alone or in admixture of two or more. Among these, methyl ethyl ketone oxime can be preferably used.

  Such a reaction between the blocking agent and the isocyanate curing agent component can be performed, for example, at 20 to 200 ° C., using a known inert solvent or catalyst, if necessary. The blocking agent is preferably used in a molar amount of 0.7 to 1.5 times the terminal isocyanate group.

(Mixing ratio)
In the adhesive used in the present invention, the blending ratio of the polyester resin (A) and the curing agent (B) is such that the polyester resin (A) and the curing agent (B) are A: B = 90: 10 to 99: 1. It is preferable to use what is blended in. When the curing agent component (B) is less than the above range, it is not possible to form an adhesive having excellent corrosion resistance, and when the curing agent component (B) is more than the above range, It is not possible to form an adhesive excellent in adhesiveness and workability.

  In the adhesive used in the present invention, the solvent is preferably contained in an amount of 150 to 550 parts by weight per 100 parts by weight of the resin component. If the amount of the solvent is less than the above range, adhesion workability is lowered, and it is difficult to form an adhesive layer having excellent adhesion and corrosion resistance. On the other hand, if the amount of the solvent is larger than the above range, it is difficult to form an adhesive layer having a sufficient thickness, and a large amount of solvent is required.

  As the solvent, any solvent known per se can be used as long as it can dissolve the above-described resin component. Although the following can be used suitably, of course, it is not limited to this example. Isopropyl alcohol (IPA), isobutyl acetate, n-butanol, ethylene glycol monoisopropyl ether (GIP), methoxypropyl acetate, cyclohexanone, Solvesso 100, DBE (dibasic acid ester), diethylene glycol monobutyl ether (BDG), butyl diglycol acetate A variety of solvents having different boiling points are used.

  The adhesive used in the present invention can be applied to the resin-coated aluminum plate or the molded lid member by any means such as spray coating, brush coating, dip coating, or roller coating. The thickness of the coating can generally be in the range of 1 to 20 μm, especially 3 to 15 μm on a dry matter basis. The baking conditions after the application are generally appropriately selected from a temperature of 150 to 300 ° C. and a baking time of 0.2 to 30 minutes.

Hereinafter, the adhesive of the present invention will be described in detail with reference to Examples and Comparative Examples.
[Production of polyester resin]
A stainless steel autoclave equipped with a stirrer, a thermometer and a partial reflux condenser is appropriately charged with raw materials such as polybasic acids, polybasic acid esters, polyhydric alcohols, and catalysts, and heated to a reaction temperature of 210 to 210. Various polyester resins were synthesized by adjusting in a range of 250 ° C., reduced pressure of 2 mmHg or less, and reaction time of 3 to 6 hours. Table 2 shows the resin composition, number average molecular weight (Mn), and glass transition temperature (Tg) of the obtained polyester resin. The composition of the polyester resin was determined by NMR (nuclear magnetic resonance absorption). The number average molecular weight (Mn) of the polyester resin was determined by GPC (gel permeation chromatography). Chloroform was used as a developing solvent at this time, and Mn in terms of styrene was determined from a calibration curve using a styrene standard sample. The glass transition temperature (Tg) of the polyester resin was determined by differential thermal analysis (DSC) using a differential scanning calorimeter. The measurement conditions at this time were a heating rate of 10 ° C./min and a measurement temperature range of 20 to 300 ° C.

[Adhesion test]
The lid member on which the insulator is mounted by the insert injection method is fixed to an inspection jig in which a sealed portion is formed by fixing a curled portion of the lid member. Air is fed into the sealed portion, and the air pressure is gradually increased from 0.1 MPa. The expansion and deformation of the lid member proceed, and the air pressure is checked when the adhesive state cannot be maintained between the insulator and the lid member and air leakage occurs. If no air leakage occurs even when the pressure is increased to a predetermined pressure, it is determined that the adhesiveness is good.

Example 1
100 mol% of terephthalic acid as dicarboxylic acid component, 60 mol% of propylene glycol as glycol component, 30 mol% of ethylene glycol, 10 mol% of CHDM (cyclohexanedimethanol), and 0.2 mol% of trimethylolpropane per glycol component IPDI (isophorone diisocyanate) blocked with MEK oxime by dissolving a polyester resin having a number average molecular weight (Mn) of 13,000 and a Tg of 61 ° C. in a 1/1/1 mixed solvent of cyclohexanone / solvesso 100 / methoxypropyl acetate Trimer (isocyanurate) and acid value titanium were added and mixed well to prepare a polyester resin.
The compounding ratio of the polyester resin and the block IPDI trimer was 90:10, and the acid value titanium was compounded by 40 parts by weight per resin component. The resulting paint had a solids content of 42% by weight and a # 4 Ford Cup viscosity of 63 seconds.
The polyester resin was applied to a polyester resin-coated aluminum plate having a thickness of 0.50 mm and baked under the conditions of 200 ° C. for 8 minutes. Thereafter, the resin-coated aluminum plate was punched into a rectangular plate with a press and formed into a desired lid shape, and a concave portion and a through hole were formed in the central portion using a mold to obtain a lid member. Further, the lid member was mounted in a mold, and a polyethylene terephthalate resin melted in a through-hole formed in the lid member was molded by an insert injection method and mounted so as to be integrated with the lid member.
The results of Example 1 are shown in Table 2 together with the polyester composition and the curing agent resin.

(Examples 2 to 7)
Evaluation was carried out in the same manner as in Example 1 by using the adhesives of Examples 2 to 7 whose detailed compositions are shown in Table 2 and bonding the insulators. In Example 5, HDI (hexamethylene diisocyanate) trimer (isocyanurate body) blocked with MEK oxime was used as a curing agent.
Examples 6 and 7 are examples in which another curing agent was used instead of the polyisocyanate curing agent. In Example 6, m-cresol phenol resin having Mn 700 and Mw (weight average molecular weight) 1350 was used as a curing agent. The number of formaldehyde added was 2.5 per phenol nucleus, and the methylol group used was completely butyl etherified.
In Example 7, a mixture of a benzoguanamine resin (Mycote 106 manufactured by Mitsui Cytec Co., Ltd.) and a melamine resin (Cymel 325 manufactured by Mitsui Cytec Co., Ltd.) whose compositions are shown in Table 2 was used as a curing agent.
Table 2 shows the details of the results. The insulators using the adhesives of Examples 1 to 7 had good adhesion.

(Comparative Example 1)
In the same manner as in Example 1, the adhesive performance of Comparative Example 1 whose detailed composition is shown in Table 2 was used and adhered to an insulator to evaluate the adhesive performance. In Comparative Example 1, the same polyester resin as in Example 1 was used, but this was a case where the curing agent of the present invention (B) was not used, resulting in poor adhesion.

According to the present invention, since an insulator made of polyethylene terephthalate resin is used, the battery contents have excellent corrosion resistance even with respect to an electrolytic solution mainly composed of highly corrosive propylene carbonate salt, and the contents. Improves leakage resistance.
The battery container according to the present invention uses an insulator made of polyethylene terephthalate resin and bonds the insulator to a lid member made of a polyester resin-coated aluminum plate using an adhesive having a specific composition. It can be firmly bonded to the through-hole of the member and has excellent leakage resistance of the battery contents.

It is a perspective view which shows the decomposition | disassembly block diagram of the battery container of this invention. The top view (a) of the insulator of this invention and its AA sectional drawing (b) are shown.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Lid member 2 Can body part 2f Flange 3 Through-hole 4 Insulator 4a Ring 4b Cavity part 4c Annular recessed part 5a Electrode 5b Electrode

Claims (4)

An insulator for electrode attachment used for a battery container, which is made of polyethylene terephthalate resin. A battery container in which a lid member formed of a polyester resin-coated aluminum plate is double-tightened and attached to an opening of a can body portion, and a through-hole provided by drilling a central portion of the lid member A battery container in which an insulator made of polyethylene terephthalate resin for electrode attachment is attached via an adhesive obtained by blending (B) a curing agent with the following (A) resin.
(A) A polyester resin comprising a dicarboxylic acid component mainly composed of terephthalic acid and a glycol component, and having a glass transition temperature in the range of 30 to 110 ° C. (B) consisting of at least one of a phenol resin, an amino resin, and a polyisocyanate resin. Hardener A battery container in which a lid member formed of a polyester resin-coated aluminum plate is double-tightened and attached to an opening of a can body portion, and a through-hole provided by drilling a central portion of the lid member A battery container in which an insulator made of polyethylene terephthalate resin for electrode attachment is attached via an adhesive obtained by blending (B) a curing agent with the following (A) resin.
(A) It consists of a dicarboxylic acid component of 80-100 mol% terephthalic acid and a glycol component, has a glass transition temperature in the range of 30 to 110 ° C., and consists of a polyester resin (B) polyisocyanate resin having a number average molecular weight of 8000 to 30000. Hardener The battery container according to claim 2 or 3, wherein the adhesive has a weight ratio of (A) :( B) in the range of 90:10 to 99: 1.

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