MODIFIED POLYVINYL ACETAL RESIN, STORAGE BATTERY ELECTRODE COMPOSITION, PIGMENT COMPOSITION

Abstract

The present invention aims to provide a composition for a storage battery electrode and a pigment composition each containing a modified polyvinyl acetal resin that has excellent dispersing properties, adhesion, and stability over time and that is capable of preventing degradation caused by an electrolyte solution when used for an electrode of a storage battery, enabling the production of a high-power storage battery. Provided is a modified polyvinyl acetal resin including a chlorine atom-containing structural unit.

Claims

1. A modified polyvinyl acetal resin comprising a chlorine atom-containing structural unit.

2. The modified polyvinyl acetal resin according to claim 1, containing the chlorine atom-containing structural unit in an amount of 0.1 mol % or more.

3. The modified polyvinyl acetal resin according to claim 1, containing the chlorine atom-containing structural unit in an amount of 35 mol % or less.

4. The modified polyvinyl acetal resin according to claim 1, wherein the chlorine atom-containing structural unit is a structure having a chlorine atom bonded via an acetal bond.

5. The modified polyvinyl acetal resin according to claim 1, wherein the chlorine atom-containing structural unit has a structure represented by the following formula (3): ##STR00004## wherein R.sup.6 represents a chlorine atom-containing hydrocarbon group.

6. The modified polyvinyl acetal resin according to claim 4, wherein the chlorine atom-containing structural unit has a structure represented by the following formula (1): ##STR00005## wherein R.sup.1 represents a chlorine atom or a chloroalkyl group, and R.sup.2 and R.sup.3 each independently represent a hydrogen atom or a chlorine atom.

7. The modified polyvinyl acetal resin according to claim 6, wherein in the formula (1), R.sup.1 is a chlorine atom, —CH.sub.2Cl, or —CH.sub.2CH.sub.2Cl.

8. The modified polyvinyl acetal resin according to claim 5, wherein in the formula (3), R.sup.6 is a chlorophenyl group or a chloroalkyl phenyl group.

9. The modified polyvinyl acetal resin according to claim 1, wherein the chlorine atom-containing structural unit has a structure represented by the following formula (2): ##STR00006## wherein R.sup.4 represents a single bond or an alkylene group, and R.sup.5 represents a hydrogen atom, a chlorine atom, or a chloroalkyl group.

10. The modified polyvinyl acetal resin according to claim 1, having a degree of polymerization of 200 to 4,000.

11. The modified polyvinyl acetal resin according to claim 1, having a hydroxy group content of 20 to 70 mol %.

12. The modified polyvinyl acetal resin according to claim 1, having a degree of non-chlorination acetalization of 20 to 75 mol %.

13. The modified polyvinyl acetal resin according to claim 1, having a chlorine atom content A measured by combustion ion chromatography of 0.1 to 15% by weight.

14. A composition for a storage battery electrode, the composition comprising: the modified polyvinyl acetal resin according to claim 1; an organic solvent; and an active material.

15. A pigment composition comprising: the modified polyvinyl acetal resin according to claim 1; an organic solvent; and a pigment.

16. A composition for a storage battery electrode, the composition comprising: the modified polyvinyl acetal resin according to claim 1; a polyvinylidene fluoride resin; an organic solvent; and an active material.

Description

DESCRIPTION OF EMBODIMENTS

[0129] The present invention is more specifically described in the following with reference to, but not limited to, examples.

Production Example 1

(Preparation of Chlorine-Modified Polyvinyl Acetal Resin)

[0130] An amount of 120 g of a polyvinyl alcohol (a) having a degree of saponification of 98.6 mol % and a degree of polymerization of 300 was added to 1,400 g of pure water and stirred at a temperature of 90° C. for about two hours for dissolution. This solution was cooled to 40° C. To the solution were then added 100 g of hydrochloric acid having a concentration of 35% by weight, 50 g of n-butyraldehyde, and 28 g of chloroacetaldehyde dimethyl acetal. Acetalization reaction was performed with the solution temperature maintained at 50° C. to precipitate a reaction product. The liquid temperature was then maintained at 50° C. for six hours to complete the reaction, followed by neutralization, washing with water, and drying by conventional methods to give powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit. The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0131] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 2

[0132] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that 45 g of n-butyraldehyde and 57 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0133] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0134] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 3

[0135] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that 55 g of n-butyraldehyde and 30 g of chloral hydrate were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0136] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0137] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═Cl, R.sup.3═Cl).

Production Example 4

[0138] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that 57 g of n-butyraldehyde and 15 g of 3-chloropropionaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0139] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0140] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═CH.sub.2Cl, R.sup.2═H, R.sup.3═H).

Production Example 5

[0141] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that 58 g of n-butyraldehyde and 12 g of 4-chlorobutyraldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0142] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0143] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1 ═CH.sub.2CH.sub.2Cl, R.sup.2═H, R.sup.3═H).

Production Example 6

[0144] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (b) having a degree of saponification of 98.6 mol % and a degree of polymerization of 800 was used instead of the polyvinyl alcohol (a), and that 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0145] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0146] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 7

[0147] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (c) having a degree of saponification of 88.8 mol % and a degree of polymerization of 800 was used instead of the polyvinyl alcohol (a), and that 35 g of n-butyraldehyde and 25 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0148] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0149] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 8

[0150] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 44 g of n-butyraldehyde, 12 g of acetaldehyde, and 27 g of chloroacetaldehyde dimethyl acetal were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0151] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, the acetoacetal group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0152] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 9

(Synthesis of Modified Polyvinyl Alcohol (d))

[0153] A flask equipped with a stirrer, a thermometer, a dropping funnel, and a reflux condenser was charged with 1,000 parts by weight of vinyl acetate, 90 parts by weight of vinyl chloride, and 300 parts by weight of methanol. The system was purged with nitrogen and then the temperature was increased to 60° C. To this system was added 1.1 parts by weight of 2,2-azobisisobutyronitrile to start polymerization. After five hours from the start of the polymerization, the polymerization was terminated. The solid concentration in the system when the polymerization was terminated was 53% by weight, and the polymerization yield relative to all the monomers was 65% by weight. After the unreacted monomers were removed under reduced pressure, a 45% by weight solution of the copolymer in methanol was obtained. The obtained copolymer was found to contain 92.4 mol % of a vinyl acetate unit and 7.6 mol % of a vinyl chloride unit by quantification of the unreacted monomers.

[0154] While 100 parts by weight of the solution of the copolymer in methanol was stirred at 40° C., 25 parts by weight of a 3% NaOH solution in methanol was added and sufficiently mixed. The mixture was then left to stand. After 30 minutes, the solidified polymer was pulverized with a pulverizer, washed with methanol, and dried to give polymer powder (hereinafter referred to as a modified polyvinyl alcohol (d)).

[0155] The modified polyvinyl alcohol (d) had a degree of saponification of 98.5 mol %, an amount of a chlorine-modified side-chain-bond unit of 7.6 mol %, and a degree of polymerization of 800.

[0156] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that the modified polyvinyl alcohol (d) was used instead of the polyvinyl alcohol (a), and that 53 g of n-butyraldehyde was added.

[0157] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0158] The chlorine atom-containing structural unit was a structural unit represented by the formula (2) (R.sup.4=single bond, R.sup.5═H).

Production Example 10

[0159] A solution of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit (resin content: 5% by weight) was obtained as in Production Example 1 except that a modified polyvinyl alcohol (e) including a chlorine atom-containing structural unit and having a degree of saponification of 98.5 mol %, an amount of a chlorine-modified side-chain-bond unit of 3.9 mol %, and a degree of polymerization of 800 was used instead of the polyvinyl alcohol (a), and that 64 g of n-butyraldehyde was added.

[0160] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0161] The chlorine atom-containing structural unit was a structural unit represented by the formula (2) (R.sup.4═CH.sub.2, R.sup.5 ═H).

Production Example 11

[0162] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 5 g of n-butyraldehyde, 18 g of acetaldehyde, and 52 g of chloroacetaldehyde dimethyl acetal were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0163] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, the acetoacetal group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0164] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 12

[0165] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (f) having a degree of saponification of 98.6 mol % and a degree of polymerization of 1,800 was used instead of the polyvinyl alcohol (a), and that 48 g of n-butyraldehyde and 26 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0166] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0167] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 13

[0168] Power of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (g) having a degree of saponification of 99.5 mol % and a degree of polymerization of 1,800 was used instead of the polyvinyl alcohol (a), and that 24 g of n-butyraldehyde and 20 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0169] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0170] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.2═Cl, R.sup.2═H, R.sup.3═H).

Production Example 14

[0171] Powder of a chlorine-modified polyvinyl acetal resin including chlorine atom-containing structural units was obtained as in Production Example 1 except that a modified polyvinyl alcohol (h) including a chlorine atom-containing structural unit and having a degree of saponification of 98.6 mol %, an amount of a chlorine-modified side-chain-bond unit of 5.4 mol %, and a degree of polymerization of 1,800 was used instead of the polyvinyl alcohol (a), and that 45 g of n-butyraldehyde and 14 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0172] The obtained polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0173] The chlorine atom-containing structural units were a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H) and a structural unit represented by the formula (2) (R.sup.4=single bond, R.sup.5═H).

Production Example 15

[0174] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 12 except that 80 g of n-butyraldehyde and 5 g of chloroacetaldehyde dimethyl acetal were added instead of 48 g of n-butyraldehyde and 26 g of chloroacetaldehyde dimethyl acetal.

[0175] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0176] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 16

[0177] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (i) having a degree of saponification of 98.2 mol % and a degree of polymerization of 2,700 was used instead of the polyvinyl alcohol (a), and that 47 g of n-butyraldehyde and 1 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0178] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0179] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 17

[0180] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a modified polyvinyl alcohol (j) including a chlorine atom-containing structural unit and having a degree of saponification of 98.3 mol %, an amount of a chlorine-modified side-chain-bond unit of 0.8 mol %, and a degree of polymerization of 2,700 was used instead of the polyvinyl alcohol (a), and that 62 g of n-butyraldehyde was added.

[0181] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0182] The chlorine atom-containing structural unit was a structural unit represented by the formula (2) (R.sup.4=single bond, R.sup.5═H).

Production Example 18

[0183] Power of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a polyvinyl alcohol (k) having a degree of saponification of 98.7 mol % and a degree of polymerization of 4,000 was used instead of the polyvinyl alcohol (a), and that 60 g of n-butyraldehyde and 6 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0184] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0185] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 19

[0186] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 61 g of n-butyraldehyde and 0.1 g of chloroacetaldehyde dimethyl acetal were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0187] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0188] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2 ═H, R.sup.3═H).

Production Example 20

[0189] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 31 g of n-butyraldehyde and 60 g of chloroacetaldehyde dimethyl acetal were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0190] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0191] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 21

[0192] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that a modified polyvinyl alcohol (1) including a chlorine atom-containing structural unit and having a degree of saponification of 98.5 mol %, an amount of a chlorine-modified side-chain-bond unit of 0.06 mol %, and a degree of polymerization of 800 was used instead of the polyvinyl alcohol (a), and that 63 g of n-butyraldehyde was added.

[0193] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0194] The chlorine atom-containing structural unit was a structural unit represented by the formula (2) (R.sup.4=single bond, R.sup.5═H).

Production Example 22

[0195] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 53 g of n-butyraldehyde and 15 g of 4-chlorobenzaldehyde were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0196] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0197] The chlorine atom-containing structural unit was a structural unit represented by the formula (3) (R.sup.6=4-chlorophenyl).

Production Example 23

[0198] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 6 except that 53 g of n-butyraldehyde and 10 g of 3-chlorobenzaldehyde were added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0199] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0200] The chlorine atom-containing structural unit was a structural unit represented by the formula (3) (R.sup.6=3-chlorophenyl).

Production Example 24

[0201] Powder of a chlorine-modified polyvinyl acetal resin including a chlorine atom-containing structural unit was obtained as in Production Example 1 except that 30 g of n-butyraldehyde and 90 g of chloroacetaldehyde dimethyl acetal were added instead of 50 g of n-butyraldehyde and 28 g of chloroacetaldehyde dimethyl acetal.

[0202] The obtained chlorine-modified polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, the butyral group content, and the amount of the chlorine-modified acetal-bond unit. Table 1 shows the results.

[0203] The chlorine atom-containing structural unit was a structural unit represented by the formula (1) (R.sup.1═Cl, R.sup.2═H, R.sup.3═H).

Production Example 25

[0204] A polyvinyl acetal resin powder was obtained as in Production Example 6 except that 66 g of n-butyraldehyde was added instead of 51 g of n-butyraldehyde and 33 g of chloroacetaldehyde dimethyl acetal.

[0205] The obtained polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, and the butyral group content. Table 1 shows the results.

Production Example 26

[0206] A polyvinyl acetal resin powder was obtained as in Production Example 12 except that 66 g of n-butyraldehyde was added instead of 48 g of n-butyraldehyde and 26 g of chloroacetaldehyde dimethyl acetal.

[0207] The obtained polyvinyl acetal resin was dissolved in DMSO-d.sub.6 (dimethyl sulfoxide) and subjected to .sup.1H-NMR (nuclear magnetic resonance spectroscopy) to measure the hydroxy group content, the acetyl group content, and the butyral group content. Table 1 shows the results.

Production Example 27

[0208] A polyvinyl acetal resin powder was obtained by adding NaCl to a commercially available polyvinyl acetal resin (hydroxy group content: 32.9 mol %, acetyl group content: 1.8 mol %, butyral group content: 65.3 mol %) to 5% by weight.

Example 1

(Preparation of Composition for Storage Battery Electrode)

[0209] To 20 parts by weight of a resin solution containing the chlorine-modified polyvinyl acetal resin of Production Example 1 (polyvinyl acetal resin: 3 parts by weight) were added 55 parts by weight of lithium cobalt oxide (produced by Nippon Chemical Industrial Co., Ltd., CELLSEED C-5H) as an active material, 5 parts by weight of acetylene black (produced by Denka Company Limited., DENKA BLACK) as a conductivity-imparting agent, and 25 parts by weight of N-methylpyrrolidone. They were then mixed using Thinky Mixer produced by Thinky Corporation to give a composition for a storage battery electrode.

Examples 2 to 24 and Comparative Examples 1 to 3

(Preparation of Composition for Storage Battery Electrode)

[0210] A composition for a storage battery electrode was obtained as in Example 1 except that a chlorine-modified polyvinyl acetal resin of a type and in an amount shown in Table 2 was used.

Example 25

(Preparation of Composition for Storage Battery Electrode)

[0211] An amount of 15 g of the chlorine-modified polyvinyl acetal resin obtained in Production Example 2 was dissolved in 85 g of N-methylpyrrolidone to give a polyvinyl acetal resin solution.

[0212] Separately, 5 g of a polyvinylidene fluoride resin (weight average molecular weight 600,000) was dissolved in 95 g of N-methylpyrrolidone to give a polyvinylidene fluoride resin solution.

[0213] To 10 parts by weight of the obtained polyvinyl acetal resin solution (polyvinyl acetal resin: 1.5 parts by weight) was added 30 parts by weight of the polyvinylidene fluoride resin solution (polyvinylidene fluoride resin: 1.5 parts by weight). Further, 55 parts by weight of lithium cobalt oxide (produced by Nippon Chemical Industrial Co., Ltd., CELLSEED C-5H) as an active material, 5 parts by weight of acetylene black (produced by Denka Company Limited., DENKA BLACK) as a conductivity-imparting agent, and 5 parts by weight of N-methylpyrrolidone were added. They were then mixed using Thinky Mixer produced by Thinky Corporation to give a composition for a storage battery electrode.

Example 26

[0214] A polyvinyl acetal resin solution and a polyvinylidene fluoride resin solution were prepared and a composition for a storage battery electrode was obtained as in Example 25 except that the chlorine-modified polyvinyl acetal resin obtained in Production Example 13 was used instead of the chlorine-modified polyvinyl acetal resin obtained in Production Example 2.

Example 27

[0215] A polyvinyl acetal resin solution and a polyvinylidene fluoride resin solution were prepared and a composition for a storage battery electrode was obtained as in Example 25 except that the chlorine-modified polyvinyl acetal resin obtained in Production Example 18 was used instead of the chlorine-modified polyvinyl acetal resin obtained in Production Example 2.

Example 28

[0216] A polyvinyl acetal resin solution and a polyvinylidene fluoride resin solution were prepared and a composition for a storage battery electrode was obtained as in Example 26 except that a polyvinylidene fluoride resin (weight average molecular weight 1,000,000) was used instead of the polyvinylidene fluoride resin (weight average molecular weight 600,000).

Example 29

[0217] A composition for a storage battery electrode was obtained as in Example 1 except that the chlorine-modified polyvinyl acetal resin obtained in Production Example 12 was used, and that 13.3 parts by weight of the polyvinyl acetal resin solution (polyvinyl acetal resin: 2 parts by weight) was added instead of 20 parts by weight of the polyvinyl acetal resin solution (polyvinyl acetal resin: 3 parts by weight) when the composition for a storage battery electrode was prepared.

Example 30

[0218] A composition for a storage battery electrode was obtained as in Example 1 except that the chlorine-modified polyvinyl acetal resin obtained in Production Example 12 was used, that 26.7 parts by weight of the polyvinyl acetal resin solution (polyvinyl acetal resin: 4 parts by weight) was added instead of 20 parts by weight of the polyvinyl acetal resin solution (polyvinyl acetal resin: 3 parts by weight) when the composition for a storage battery electrode was prepared, and that 10 parts by weight of N-methylpyrrolidone was added instead of 25 parts by weight of N-methylpyrrolidone.

Comparative Example 4

[0219] An amount of 10 g of a polyvinylidene fluoride resin (weight average molecular weight 600,000) was dissolved in 90 g of N-methylpyrrolidone to give a polyvinylidene fluoride resin solution.

[0220] To 30 parts by weight of the obtained polyvinylidene fluoride resin solution (polyvinylidene fluoride resin: 3 parts by weight) were added 55 parts by weight of lithium cobalt oxide (produced by Nippon Chemical Industrial Co., Ltd., CELLSEED C-5H) as an active material, 5 parts by weight of acetylene black (produced by Denka Company Limited., DENKA BLACK) as a conductivity-imparting agent, and 5 parts by weight of N-methylpyrrolidone. They were then mixed using Thinky Mixer produced by Thinky Corporation to give a composition for a storage battery electrode.

Examples 31 to 46 and Comparative Examples 5 to 7

(Preparation of Pigment Composition)

[0221] An amount of 2.25 g of one of the (modified) polyvinyl acetal resins obtained in Production Examples 1 to 11, 19 to 23, and 25 to 27 as shown in Table 3, 22.5 g of a pigment, and 147.75 g of an organic solvent were mixed and stirred using a stirring device for one hour to prepare a pigment dispersion.

[0222] The pigment used was Pigment Green 7 (produced by Resino Color Industry Co., Ltd., phthalocyanine green, average particle size 80 μm). The organic solvent used was benzyl alcohol.

<Evaluation>

[0223] The following evaluations were performed on the (modified) polyvinyl acetal resins obtained in the production examples and the compositions for a storage battery electrode and the pigment compositions obtained in the examples and the comparative examples. Tables 2 and 3 show the results.

(1) Measurement of Chlorine Atom Contents (Chlorine Atom Contents A and B) of Resin

[0224] The obtained polyvinyl acetal resin was subjected to combustion ion chromatography to measure the chlorine atom content A in conformity with JIS K 0127(2013). The sample combustion device used was AQF-100 (produced by Mitsubishi Chemical Analytech Co., Ltd.). The ion chromatograph used was ICS-1500 (produced by Dionex Corporation), and the ion exchange column used was Dionex IonPac AS12A (produced by Thermo Fisher Scientific K.K.).

[0225] Separately, a chlorine atom content was calculated from the chlorine-modified unit content obtained by .sup.1H-NMR, and used as the chlorine atom content B.

[0226] Further, from the chlorine atom content A and the chlorine atom content B, the chlorine atom content difference C was calculated using the following formula (4).

Chlorine atom content difference C=Chlorine atom content A−Chlorine atom content B  (4)

(2) Evaluation of Composition for Storage Battery Electrode

(2-1) Adhesion (Peeling Force)

[0227] The obtained composition for a storage battery electrode was evaluated for the adhesion to aluminum foil.

[0228] The composition for an electrode was applied to aluminum foil (thickness: 20 μm) to a dried thickness of 20 μm, and dried to prepare a specimen having a sheet-like electrode formed on the aluminum foil.

[0229] The specimen was cut to a size of 1 cm in length and 2 cm in width. Using AUTOGRAPH (“AGS-J” produced by Shimadzu Corporation), the electrode sheet was pulled up with the specimen being fixed, and the peeling force (N) needed for completely peeling the electrode sheet from the aluminum foil was measured. The adhesion was then evaluated based on the following criteria.

∘ (Good): A peeling force of 8.0 N or greater
Δ (Fair): A peeling force of less than 8.0 and greater than 6.0 N
x (Poor): A peeling force of 6.0 N or less

(2-2) Dispersing Properties (Surface Roughness)

[0230] The surface roughness Ra of the specimen obtained in “(2-1) Adhesion” was measured in conformity with JIS B 0601(1994). The electrode surface roughness was evaluated in accordance with the following criteria. Typically, the higher the dispersibility of the active material, the lower the surface roughness.

∘ (Good): A Ra of less than 3.0 μm
Δ (Fair): A Ra of 3.0 μm or greater and less than 4.0 μm
x (Poor): A Ra of 4.0 μm or greater

(2-3) Resistance Against Electrolyte Solution (Solubility in Solvent)

(Preparation of Electrode Sheet)

[0231] The compositions for a storage battery electrode obtained in the examples and the comparative examples were each applied to a release-treated polyalkylene terephthalate (PET) film to a dried film thickness of 20 μm and dried to prepare an electrode sheet.

[0232] The electrode sheet was cut into a 2-cm square electrode sheet specimen.

(Elution Evaluation)

[0233] The obtained specimen was accurately weighed, and the weight of the resin contained in the specimen was calculated from the weight ratio between the components contained in the sheet. Then, the specimen was placed in a mesh bag, and the sum of the weight of the mesh bag and the weight of the specimen was accurately measured.

[0234] The mesh bag containing the specimen was immersed in a solvent mixture (diethyl carbonate:alkylene carbonate=1:1), which is a solvent of an electrolyte solution, and left to stand at 60° C. for five hours. After the standing, the mesh bag was taken out and dried under the conditions of 150° C. and eight hours to completely vaporize the solvent.

[0235] The mesh bag was taken out from the dryer, left to stand at room temperature for one hour, and weighed. The amount of the eluted resin was calculated based on the weight change before and after the test, and the resin elution rate was calculated based on the ratio between the amount of the eluted resin and the weight of the resin calculated in advance. The obtained elution rate was evaluated in accordance with the following criteria.

∘ (Good): An elution rate of less than 1.0%
Δ (Fair): An elution rate of 1.0% or greater and less than 2.0%
x (Poor): An elution rate of 2.0% or greater

(2-4) Measurement of Electrode Resistance

[0236] The electrode resistance of the specimen obtained in “(2-1) Adhesion” was measured using an electrode resistance meter (produced by Hioki E.E. Corp.) and evaluated in accordance with the following criteria.

∘∘ (Excellent): An electrode resistance of less than 400 Ω/sq
∘ (Good): An electrode resistance of 400 Ω/sq or greater and less than 700 Ω/sq
Δ (Fair): An electrode resistance of 700 Ω/sq or greater and less than 1,000 Ω/sq
x (Poor): An electrode resistance of 1,000 Ω/sq or greater

(3) Evaluation of Battery Performance

(Preparation of Coin Cell)

[0237] The compositions for a storage battery electrode obtained in Examples 2, 3, 9, 11 to 13, 16, 18, 22, and 25 to 30 and Comparative Examples 1 to 4 were each applied to aluminum foil (thickness 20 μm) and dried to give a positive electrode sheet having a dried thickness of 80 μm. A piece (φ11 mm) was punched out from this positive electrode sheet to give a positive electrode layer. Separately, a piece (φ11 mm) was punched out from a metal lithium foil having a thickness of 100 μm to give a negative electrode layer. A solvent mixture (EC:DEC:EMC=3:4:3) containing 1 mol/L of LiPF.sub.6 was used an electrolyte solution. A positive electrode collector, the positive electrode layer, a porous PP membrane separator (thickness 25 μm), the negative electrode layer, and a negative electrode current collector were sequentially stacked. They are compressed using a crimper to prepare a sealed coin cell.

(Charge/Discharge Cycle Evaluation)

[0238] The obtained coin cell was subjected to a charge/discharge cycle evaluation using a charge/discharge test device (produced by Hokuto Denko Corp.) in a voltage range from 3.0 to 4.2 V at a temperature of 25° C. The ratio of capacity at the 300th cycle relative to the discharge capacity at the first cycle was calculated as the capacity retention (%).

[0239] The coin cell of Comparative Example 3 contained large amounts of Na ions and Cl ions, which adversely affect the battery performance, and thus showed a great decrease in capacity before 10 cycles after the start of the evaluation. The coin cell of Comparative Example 3 was thus evaluated “Not measurable.”

(4) Evaluation of Pigment Composition

(4-1) Dispersing Properties

[0240] The obtained pigment composition was diluted 100-fold. The average particle size (D50) was measured using a particle size distribution analyzer (produced by Shimadzu Corporation, SALD-7100) and evaluated in accordance with the following criteria.

∘∘ (Excellent): An average particle size of less than 300 μm
∘ (Good): An average particle size of 300 μm or greater and less than 350 μm
Δ (Fair): An average particle size of 350 μm or greater and less than 400 μm
x (Poor): An average particle size of 400 μm or greater, or coagulation

(4-2) Stability Over Time (Viscosity Increase Over Time)

[0241] The initial viscosity (Pa.Math.s) of the obtained pigment composition was measured using a cone and plate viscometer Gemini (produced by Bohlin Instruments) at 25° C. and a shear rate of 20 s.sup.−1.

[0242] The viscosity (Pa.Math.s) of the obtained pigment composition 30 days after the measurement of the initial viscosity was measured in the same manner. The viscosity change rate (%) was determined and evaluated in accordance with the following criteria.

∘ (Good): A viscosity change rate of less than 10%
Δ (Fair): A viscosity change rate of 10% or greater and less than 15%
x (Poor): A viscosity change rate of 15% or greater

TABLE-US-00001 TABLE 1 Chlorination-modified Degree side-chain-bond unit of Chlorination-modified acetal-bond unit Con- PVA poly- R.sup.1 R.sup.2 R.sup.3 R.sup.5 tent type mer- struc- struc- struc- R.sup.6 Content R.sup.4 struc- (mol used ization ture ture ture structure (mol %) structure ture %) Production Example 1 (a) 300 Cl H H — 12.4 — — 0 Production Example 2 (a) 300 Cl H H — 26.2 — — 0 Production Example 3 (a) 300 Cl Cl Cl — 4.1 — — 0 Production Example 4 (a) 300 CH.sub.2Cl H H — 6.3 — — 0 Production Example 5 (a) 300 CH.sub.2CH.sub.2Cl H H — 4.5 — — 0 Production Example 6 (b) 800 Cl H H — 17.8 — — 0 Production Example 7 (c) 800 Cl H H — 14.1 — — 0 Production Example 8 (b) 800 Cl H H — 14.7 — — 0 Production Example 9 (d) 800 — — — — 0 Single bond H 7.6 Production Example 10 (e) 800 — — — — 0 CH.sub.2 H 3.9 Production Example 11 (b) 800 Cl H H — 27.3 — — 0 Production Example 12 (f) 1800 Cl H H — 14.7 — — 0 Production Example 13 (g) 1800 Cl H H — 10.4 — — 0 Production Example 14 (h) 1800 Cl H H — 7.2 Single bond H 5.4 Production Example 15 (f) 1800 Cl H H — 2.4 — — 0 Production Example 16 (i) 2700 Cl H H — 0.3 — — 0 Production Example 17 (j) 2700 — — — — 0 Single bond H 0.8 Production Example 18 (k) 4000 Cl H H — 5.2 — — 0 Production Example 19 (b) 800 Cl H H — 0.05 — — 0 Production Example 20 (b) 800 Cl H H — 32.8 — — 0 Production Example 21 (l) 800 — — — — 0 Single bond H 0.06 Production Example 22 (b) 800 — — — 4-Chlorophenyl 5.8 — — 0 Production Example 23 (b) 800 — — — 3-Chlorophenyl 3.5 — — 0 Production Example 24 (a) 300 Cl H H — 49.3 — — 0 Production Example 25 (b) 800 — — — 0 — — 0 Production Example 26 (f) 1800 — — — 0 — — 0 Production Example 27 — 800 — — — 0 — — 0 Chlo- rine Degree Hy- Chlo- Chlo- atom Chlo- Aceto- of non- Degree droxy rine rine content rination- acetal chlori- of group atom atom differ- modified Butyral group nation acetali- Acetyl con- content content ence unit group content acetali- zation group tent A B C content content (mol zation (mol content (mol (% by (% by (% by (mol %) (mol %) %) (mol %) %) (mol %) %) weight) weight) weight) Production Example 1 12.4 49.8 0 49.8 62.2 1.4 36.4 3.6 3.6 0.0 Production Example 2 26.2 43.4 0 43.4 69.6 1.2 29.2 7.4 7.3 0.1 Production Example 3 4.1 54.3 0 54.3 58.4 1.2 40.4 3.5 3.5 0.0 Production Example 4 6.3 56.6 0 56.6 62.9 1.5 35.6 1.9 1.8 0.1 Production Example 5 4.5 57.1 0 57.1 61.6 1.6 36.8 1.3 1.3 0.0 Production Example 6 17.8 50.3 0 50.3 68.1 1.3 30.6 5.1 5.0 0.1 Production Example 7 14. 35.9 0 35.9 50.0 11.2 38.8 4.2 4.0 0.2 Production Example 8 14.7 43.1 16.6 59.7 74.4 1.7 23.9 4.2 4.1 0.1 Production Example 9 7.6 51.3 0 51.3 51.3 1.5 39.6 4.5 4.5 0.0 Production Example 10 3.9 62.4 0 62.4 62.4 1.6 32.1 2.2 2.2 0.0 Production Example 11 27.3 4.2 26.5 30.7 58.0 1.2 40.8 8.6 8.5 0.1 Production Example 12 14.7 47.3 0 47.3 62.0 1.4 36.6 4.3 4.2 0.1 Production Example 13 10.4 23.4 0 23.4 33.8 0.5 65.7 3.6 3.5 0.1 Production Example 14 12.6 43.8 0 43.8 51.0 1.4 42.2 5.6 5.4 0.2 Production Example 15 2.4 72.5 0 72.5 74.9 1.3 23.8 0.7 0.7 0.0 Production Example 16 0.3 46.9 0 46.9 47.2 1.8 51.0 0.1 0.1 0.0 Production Example 17 0.8 61.3 0 61.3 61.3 1.7 36.2 0.5 0.5 0.0 Production Example 18 5.2 59.4 0 59.4 64.6 1.3 34.1 1.6 1.5 0.1 Production Example 19 0.05 60.2 0 60.2 60.3 1.4 38.4 0.01 0.01 0.0 Production Example 20 32.8 30. 0 30.1 62.9 1.4 35.7 9.6 9.3 0.3 Production Example 21 0.06 62.2 0 62.2 62.2 1.5 36.2 0.03 0.03 0.0 Production Example 22 5.8 51.2 0 51.2 57.0 1.3 41.7 1.6 1.6 0.0 Production Example 23 3.5 51.9 0 51.9 55.4 1.4 43.2 1.0 1.0 0.0 Production Example 24 49.3 28.9 0 28.9 78.2 1.2 20.6 13.1 13.0 0.1 Production Example 25 0 64.7 0 64.7 64.7 1.6 33.7 0 0 0.0 Production Example 26 0 64.3 0 64.3 64.3 1.6 34.1 0 0 0.0 Production Example 27 0 65.3 0 65.3 65.3 1.8 32.9 5.0 0 5.0

TABLE-US-00002 TABLE 2 Evaluation of battery perform- Evaluation of composition for storage battery electrode ance Composition for storage battery electrode Dispersing Charge/ Polyvinyl acetal PVDF properties Resistance against discharge Addition Weight Addition Adhesion Surface electrolyte solution Electrode cycle amount average amount Peeling roughness Elution resistance Capacity (parts by molecular (parts by force Rat- Ra Rat- rate Resistivity retention Type weight) weight weight) (N) ing (μm) ing (%) Rating (Q/sq) Rating (%) Example 1 Production 3 — — 7.3 Δ 1.6 ◯ 0.8 ◯ 392 ◯◯ — Example 1 Example 2 Production 3 — — 8.0 ◯ 1.3 ◯ 0.7 ◯ 288 ◯◯ 92 Example 2 Example 3 Production 3 — — 7.4 Δ 1.9 ◯ 0.7 ◯ 454 ◯ 90 Example 3 Example 4 Production 3 — — 6.9 Δ 1.7 ◯ 0.8 ◯ 573 ◯ — Example 4 Example 5 Production 3 — — 6.8 Δ 1.6 ◯ 0.9 ◯ 601 ◯ — Example 5 Example 6 Production 3 — — 8.9 ◯ 1.7 ◯ 0.8 ◯ 349 ◯◯ — Example 6 Example 7 Production 3 — — 9.1 ◯ 1.9 ◯ 1.3 Δ 458 ◯ — Example 7 Example 8 Production 3 — — 8.6 ◯ 1.7 ◯ 1.6 Δ 397 ◯◯ — Example 8 Example 9 Production 3 — — 8.6 ◯ 2.0 ◯ 0.7 ◯ 544 ◯ 91 Example 9 Example 10 Production 3 — — 8.5 ◯ 2.1 ◯ 1.1 Δ 667 ◯ — Example 10 Example 11 Production 3 — — 9.0 ◯ 1.5 ◯ 0.7 ◯ 248 ◯◯ 94 Example 11 Example 12 Production 3 — — 10.1 ◯ 2.2 ◯ 0.8 ◯ 353 ◯◯ 93 Example 12 Example 13 Production 3 — — 11.3 ◯ 2.3 ◯ 0.5 ◯ 409 ◯ 96 Example 13 Example 14 Production 3 — — 10.8 ◯ 2.2 ◯ 0.9 ◯ 346 ◯◯ — Example 14 Example 15 Production 3 — — 10.5 ◯ 2.5 ◯ 1.9 Δ 590 ◯ — Example 15 Example 16 Production 3 — — 11.9 ◯ 2.8 ◯ 0.9 ◯ 672 ◯ 91 Example 16 Example 17 Production 3 — — 11.7 ◯ 2.9 ◯ 1.2 Δ 693 ◯ — Example 17 Example 18 Production 3 — — 13.1 ◯ 3.9 Δ 0.9 ◯ 518 ◯ 87 Example 18 Example 19 Production 3 — — 8.2 ◯ 2.0 ◯ 1.4 Δ 829 Δ — Example 19 Example 20 Production 3 — — 8.8 ◯ 1.8 ◯ 0.7 ◯ 310 ◯◯ — Example 20 Example 21 Production 3 — — 8.1 ◯ 2.2 ◯ 1.4 Δ 857 Δ — Example 21 Example 22 Production 3 — — 9.2 ◯ 1.6 ◯ 0.9 ◯ 483 ◯ 94 Example 22 Example 23 Production 3 — — 9.5 ◯ 1.5 ◯ 0.7 ◯ 549 ◯ — Example 23 Example 24 Production 3 — — 6.1 Δ 1.7 ◯ 0.6 ◯ 455 ◯◯ — Example 24 Example 25 Production 1.5 600000 1.5 11.4 ◯ 1.4 ◯ 0.5 ◯ 277 ◯◯ 94 Example 2 Example 26 Production 1.5 600000 1.5 14.8 ◯ 2.5 ◯ 0.4 ◯ 281 ◯◯ 97 Example 13 Example 27 Production 1.5 600000 1.5 15.3 ◯ 3.9 Δ 0.6 ◯ 483 ◯ 90 Example 18 Example 28 Production 1.5 1000000 1.5 16.6 ◯ 2.7 ◯ 0.3 ◯ 240 ◯◯ 97 Example 2 Example 29 Production 2 — — 8.3 ◯ 2.5 ◯ 0.8 ◯ 276 ◯◯ 93 Example 12 Example 30 Production 4 — — 14.5 ◯ 2.0 ◯ 0.9 ◯ 491 ◯ 94 Example 12 Comparative Production 3 — — 7.8 Δ 2.5 ◯ 2.3 X 1107 X 67 Example 1 Example 25 Comparative Production 3 — — 9.0 ◯ 3.1 Δ 2.0 X 1035 X 71 Example 2 Example 26 Comparative Production 3 — — 5.5 X 3.2 Δ 2.2 X 1324 X Not Example 3 Example 27 measur- able Comparative — — 600000 3 5.7 X 4.8 X 0.2 ◯ 451 ◯ 94 Example 4

TABLE-US-00003 TABLE 3 Evaluation of pigment composition Dispersing Viscosity increase properties over time Average Viscosity particle change Formulation size rate Resin type (μm) Rating (%) Rating Example 31 Production Example 1 259 ◯◯ 6.2 ◯ Example 32 Production Example 2 235 ◯◯ 5.1 ◯ Example 33 Production Example 3 312 ◯ 8.8 ◯ Example 34 Production Example 4 288 ◯◯ 7.5 ◯ Example 35 Production Example 5 274 ◯◯ 9.5 ◯ Example 36 Production Example 6 332 ◯ 6.4 ◯ Example 37 Production Example 7 339 ◯ 8 ◯ Example 38 Production Example 8 335 ◯ 7 ◯ Example 39 Production Example 9 346 ◯ 9.3 ◯ Example 40 Production Example 10 366 Δ 10.3 Δ Example 41 Production Example 11 331 ◯ 5.9 ◯ Example 42 Production Example 19 390 Δ 13.7 Δ Example 43 Production Example 20 320 ◯ 5.7 ◯ Example 44 Production Example 21 394 Δ 14.1 Δ Example 45 Production Example 22 260 ◯◯ 6.1 ◯ Example 46 Production Example 23 281 ◯◯ 6.9 ◯ Comparative Example 5 Production Example 25 420 X 16.2 X Comparative Example 6 Production Example 26 632 X 14.1 Δ Comparative Example 7 Production Example 27 464 X 19.3 X

INDUSTRIAL APPLICABILITY

[0243] The present invention can provide a modified polyvinyl acetal resin having excellent dispersing properties, adhesion, and stability over time and capable of preventing degradation caused by an electrolyte solution when used for an electrode of a storage battery, enabling the production of a high-power storage battery. The present invention also can provide a composition for a storage battery electrode and a pigment composition each containing the modified polyvinyl acetal resin.