Provided is a method of making a collection of polymer beads comprising (a1) forming a first collection of monomer droplets in an aqueous medium in a container, wherein the first collection of monomer droplets has volume-average diameter DAV1 and has uniformity coefficient less than 1.3; (a2) forming a second collection of monomer droplets in the aqueous medium in the container, wherein the second collection of monomer droplets has volume-average diameter DAV2 and has uniformity coefficient less than 1.3, wherein DAV1 and DAV2 differ by 10 μm or more; wherein either step (a1) and step (a2) are performed simultaneously; or step (a2) is performed after step (a1), while the first collection of monomer droplets remains in the container; or a combination thereof; and (b) after steps (a1) and (a2), polymerizing the monomer droplets by suspension polymerization to form the polymer beads.

A curable composition includes a hygroscopic salt comprising a metal-organic framework comprising a cluster comprising zirconium and a positively charged organic ligand and an anion, to an encapsulation part having excellent anti-moisture and optical properties.

A curable composition includes a hygroscopic salt comprising a metal-organic framework comprising a cluster comprising zirconium and a positively charged organic ligand and an anion, to an encapsulation part having excellent anti-moisture and optical properties.

A curable composition includes a hygroscopic salt comprising a metal-organic framework comprising a cluster comprising zirconium and a positively charged organic ligand and an anion, to an encapsulation part having excellent anti-moisture and optical properties.

Provided is a polymerization initiator, which has an excellent curing rate and is an alternative to a polymerization initiator system using a benzoyl peroxide-aromatic amine compound, a curable composition containing the polymerization initiator, a dental material and dental filler material containing the composition, and a kit for preparing the curable composition. The polymerization initiator contains one or more compounds (A) selected from the group consisting of a pyrazolidinedione compound and/or pyrazolidine(di)thione compound (A1), a salt (A2) of the compound (A1), and a malonate compound (A3).

Provided is a polymerization initiator, which has an excellent curing rate and is an alternative to a polymerization initiator system using a benzoyl peroxide-aromatic amine compound, a curable composition containing the polymerization initiator, a dental material and dental filler material containing the composition, and a kit for preparing the curable composition. The polymerization initiator contains one or more compounds (A) selected from the group consisting of a pyrazolidinedione compound and/or pyrazolidine(di)thione compound (A1), a salt (A2) of the compound (A1), and a malonate compound (A3).

A method for setting polymerization condition includes a physical property acquiring step of, when heating a composition including a polymerization-reactive compound and a polymerization catalyst and/or a polymerization initiator and retaining heat at a predetermined temperature, acquiring a physical property value a derived from a functional group before heating of the polymerization-reactive compound and a physical property value b derived from a remaining functional group after maintaining a temperature for a predetermined time; a remaining functional group ratio calculating step of calculating a remaining functional group ratio from the physical property value a and the physical property value b; a reaction rate coefficient calculating step of calculating a reaction rate coefficient from the remaining functional group ratio on the basis of a reaction rate equation; and a polymerization temperature calculating step of calculating a polymerization temperature on the basis of the reaction rate coefficient and conditions below.

Crosslinker-accelerator system for the thermal crosslinking of polyacrylates having functional groups capable of entering into linking reactions with epoxide groups, comprising at least one substance having at least one epoxide group as crosslinker and at least one substance of the formula
R.sup.1.sub.2NCR.sup.2R.sup.3CR.sup.4R.sup.5(CR.sup.6R.sup.7).sub.nX
in which the R.sup.1 independently represent hydrogen, a substituted or unsubstituted alkyl or cycloalkyl radical or together with the nitrogen atom form a 5-7-membered ring;
R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 independently represent hydrogen or an alkyl radical having 1 to 8 carbon atoms or form a 5-7-membered cycloalkylene group;
n=0; and
X represents OH, OR, SH, SR and PR.sub.2, in which R independently represents C.sub.1-C.sub.18 alkyl radical, C.sub.2-C.sub.18 alkenyl radical or C.sub.2-C.sub.18 alkynyl radical, an aryl group or an aliphatic or aromatic heterocycle, as accelerator.

Crosslinker-accelerator system for the thermal crosslinking of polyacrylates having functional groups capable of entering into linking reactions with epoxide groups, comprising at least one substance having at least one epoxide group as crosslinker and at least one substance of the formula
R.sup.1.sub.2NCR.sup.2R.sup.3CR.sup.4R.sup.5(CR.sup.6R.sup.7).sub.nX
in which the R.sup.1 independently represent hydrogen, a substituted or unsubstituted alkyl or cycloalkyl radical or together with the nitrogen atom form a 5-7-membered ring;
R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 independently represent hydrogen or an alkyl radical having 1 to 8 carbon atoms or form a 5-7-membered cycloalkylene group;
n=0; and
X represents OH, OR, SH, SR and PR.sub.2, in which R independently represents C.sub.1-C.sub.18 alkyl radical, C.sub.2-C.sub.18 alkenyl radical or C.sub.2-C.sub.18 alkynyl radical, an aryl group or an aliphatic or aromatic heterocycle, as accelerator.

An active energy ray-curable inkjet ink containing polymerizable compounds and a polymerization initiator, wherein the polymerizable compounds include at least 5 types of polyfunctional polymerizable compounds having molecular weights within a range from 150 to 500, and include substantially no monofunctional polymerizable compounds.