A water-absorbent copolymer may include a vinyl alcohol constituent unit x and a constituent unit z other than the vinyl alcohol constituent unit x and a vinyl ester constituent unit y, wherein a ratio of a content of an average sequence of the constituent unit z to a content of the constituent unit z is 50.0 mol % or less.

The present invention provides a conductive paste which leaves less fine undissolved matter when dissolved in an organic solvent and thus can be easily filtrated, which has excellent printability, and which can exhibit excellent surface smoothness after printing. Provided is a conductive paste used for forming an electrode of a multilayer ceramic capacitor, the conductive paste containing: a polyvinyl acetal resin; an organic solvent; and a conductive powder, the polyvinyl acetal resin having a wave number A (cm.sup.−1) of a peak within a range of 3,100 to 3,700 cm.sup.−1 in an IR absorption spectrum measured using an infrared spectrophotometer; and a hydroxy group content (mol %), the wavenumber A of the peak and the hydroxy group content satisfying relations of the following formulas (1) and (2):

[(3,470−A)/Hydroxy group content]≤5.0  (1)

(3,470−A)≤150  (2)

wherein A is a wavenumber which is lower than 3,470 cm.sup.−1 and at which a transmittance a (%) satisfying [100−(100−X)/2] is exhibited, where X (%) is s minimum transmittance of the peak within the wavenumber range of 3,100 to 3,700 cm.sup.−1.

The present invention provides a conductive paste which leaves less fine undissolved matter when dissolved in an organic solvent and thus can be easily filtrated, which has excellent printability, and which can exhibit excellent surface smoothness after printing. Provided is a conductive paste used for forming an electrode of a multilayer ceramic capacitor, the conductive paste containing: a polyvinyl acetal resin; an organic solvent; and a conductive powder, the polyvinyl acetal resin having a wave number A (cm.sup.−1) of a peak within a range of 3,100 to 3,700 cm.sup.−1 in an IR absorption spectrum measured using an infrared spectrophotometer; and a hydroxy group content (mol %), the wavenumber A of the peak and the hydroxy group content satisfying relations of the following formulas (1) and (2):

[(3,470−A)/Hydroxy group content]≤5.0  (1)

(3,470−A)≤150  (2)

wherein A is a wavenumber which is lower than 3,470 cm.sup.−1 and at which a transmittance a (%) satisfying [100−(100−X)/2] is exhibited, where X (%) is s minimum transmittance of the peak within the wavenumber range of 3,100 to 3,700 cm.sup.−1.

The present invention provides a slurry composition in which magnetic material powder has excellent dispersibility and excellent dispersion stability and which enables production of a sheet having high surface smoothness and high adhesiveness to substrates. Provided is a slurry composition containing: a polyvinyl acetal resin; magnetic material powder; and a Na ion, the slurry composition having a Na ion content of 1,000 to 3,000 μg/g relative to the polyvinyl acetal resin.

The present invention provides a slurry composition in which magnetic material powder has excellent dispersibility and excellent dispersion stability and which enables production of a sheet having high surface smoothness and high adhesiveness to substrates. Provided is a slurry composition containing: a polyvinyl acetal resin; magnetic material powder; and a Na ion, the slurry composition having a Na ion content of 1,000 to 3,000 μg/g relative to the polyvinyl acetal resin.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

The present invention provides an epoxy resin composition that is provided with flexibility to combine impact resistance and mechanical strength, while maintaining epoxy resin-specific high elastic modulus, that reduces an increase in viscosity due to mixing, and that is excellent in heat resistance, storage stability, and solvent resistance. Provided is an epoxy resin composition containing: a modified polyvinyl acetal resin having a constitutional unit with an acid-modified group; a reactive diluent; and an epoxy resin, the epoxy resin composition having a sea-island phase separated structure after being cured.

A method is provided for generating aldehyde-functionalized polymers such as GPAM, wherein progress of the aldehyde-functionalized polymer formation is monitored by measuring viscosity using an online viscometer. A method is also provided for enhancing paper strength, said method comprising generating an aldehyde-functionalized polymer, such as GPAM, according to the present disclosure, and combining said aldehyde-functionalized polymer with a fiber slurry or applying it to a paper sheet.

A method is provided for generating aldehyde-functionalized polymers such as GPAM, wherein progress of the aldehyde-functionalized polymer formation is monitored by measuring viscosity using an online viscometer. A method is also provided for enhancing paper strength, said method comprising generating an aldehyde-functionalized polymer, such as GPAM, according to the present disclosure, and combining said aldehyde-functionalized polymer with a fiber slurry or applying it to a paper sheet.

A method is provided for generating aldehyde-functionalized polymers such as GPAM, wherein progress of the aldehyde-functionalized polymer formation is monitored by measuring viscosity using an online viscometer. A method is also provided for enhancing paper strength, said method comprising generating an aldehyde-functionalized polymer, such as GPAM, according to the present disclosure, and combining said aldehyde-functionalized polymer with a fiber slurry or applying it to a paper sheet.