An object of the present invention is to provide a golf ball exhibiting good shot feeling and excellent resilience. The present invention provides a golf ball comprising a spherical core and one or more cover layers disposed outside the spherical core, wherein at least one layer of the cover layers contains: (A) a base resin containing (a-1) an ionomer resin and having a material hardness of 59 or more in Shore D hardness; and (B) a polyrotaxane having a cyclodextrin with at least a part of hydroxyl groups of the cyclodextrin being modified with a caprolactone chain having a carboxyl group at a terminal of the caprolactone chain, a linear molecule piercing through a cyclic structure of the cyclodextrin, and blocking groups located at both terminals of the linear molecule to prevent disassociation of the cyclodextrin.

An object of the present invention is to provide a golf ball showing improved controllability on approach shots for less than 40 yards, in particular, on approach shots around the green (about 10 yards to 20 yards) and improved controllability on approach shots from the rough, and showing excellent shot feeling. The present invention provides a golf ball comprising a golf ball body and a paint film covering the golf ball body, wherein a loss tangent tans has a peak temperature of 50 C. or less and a peak height of less than 0.8, obtained by measuring dynamic viscoelasticity of the paint film under the following conditions:

<Measuring Conditions> Measuring mode: tensile mode Measuring temperature range: from 100 C. to 150 C. Temperature rising rate: 4 C./min Oscillation frequency: 10 Hz Measuring strain: 0.1.

To provide a urethane resin for sliding members which has high abrasion resistance and is considered that crosslinking points are uniformly dispersed so that molecular motion is suitably possible. Particularly, to provide the urethane resin can be advantageously used as a polishing pad.

There is provided the urethane resin for polishing is obtained by polymerizing a polymerizable composition comprising (A) a polyrotaxane having a composite molecular structure formed by an axial molecule and a plurality of cyclic molecules clathrating the axial molecule and side chains having an active hydrogen group introduced into at least some of the cyclic molecules and (B) a polyiso(thio)cyanate compound.

The invention provides a polymerizable composition and a hydrogel obtained or obtainable from the polymerizable composition. The polymerizable composition comprises cucurbituril and a first monomer having a guest for the cucurbituril, wherein the total monomer concentration, C.sub.mon, within the polymerizable composition is at least 0.5 M. The composition may be an aqueous composition.

A new synthetic pathway for hyperbranched polyacrylates and polymethacrylates including the steps of preparing an inimer and polymerizing the inimer to form hyperbranched polymers or copolymers.

An object of the present invention is to provide a golf ball having excellent abrasion resistance and spin performance on driver shots. The present invention provides a golf ball having a spherical core and a cover covering the spherical core, wherein the cover contains a polyurethane, wherein the polyurethane comprises, as a constituent component, (A) a polyisocyanate component and (B) a polyol component containing (b1) a polyrotaxane, and wherein (b1) the polyrotaxane has a cyclodextrin, a linear molecule piercing through the cyclic structure of the cyclodextrin, and a blocking group located at both terminals of the linear molecule to prevent disassociation of the cyclodextrin, and at least a part of hydroxyl groups of the cyclodextrin is modified with a caprolactone chain via OC.sub.3H.sub.6O group.

Provided is a self-restoring macromolecular material that not only has excellent stress relaxation but that can also be easily restored to its original state, even when damaged or severed. Also provided is a method for producing the self-restoring macromolecular material. The self-restoring macromolecular material contains a crosslinked structure that is formed by crosslinking a polymer containing at least a polyrotaxane molecule. The polyrotaxane molecule is formed so as to include a cyclic molecule 21 and a linear molecule that passes through an opening 21a of the cyclic molecule. The crosslinked structure 1 is crosslinked via a reversible bond between the cyclic molecule of the polyrotaxane molecule and a polymer molecule other than the polyrotaxane molecule.

The present invention relates to a photopolymer composition comprising: a polymer matrix or a precursor thereof including a reaction product of a polyol including a polyrotaxane compound and a compound containing at least one isocyanate group; a photoreactive monomer; and a photoinitiator. The present invention also relates to a hologram recording medium produced from the photopolymer composition, an optical element comprising the hologram recording medium, and a holographic recording method using the photopolymer composition.

The present invention provides a method for producing an aqueous dispersion of pseudopolyrotaxane that enables the production, by an industrially advantageous method for an aqueous dispersion of pseudopolyrotaxane in which the inclusion amount of a cyclodextrin does not increase with time and which can provide a crosslinked polyrotaxane having sufficient stretchability and breaking strength. The present invention relates to a method for producing an aqueous dispersion of pseudopolyrotaxane containing pseudopolyrotaxane particles in which a polyethylene glycol is included in a cavity of a cyclodextrin molecule in a skewered manner, the method including: an inclusion step of mixing a polyethylene glycol and a cyclodextrin in an aqueous medium to include the polyethylene glycol in a cavity of a cyclodextrin molecule, wherein in the inclusion step, a basic compound is added.

Provided is a photochromic curable composition which forms a cured body that develops excellent photochromic properties. The photochromic curable composition (A) includes: a polyrotaxane monomer wherein, in a polyrotaxane compound having a composite molecular structure composed of an axial molecule and a plurality of cyclic molecules threaded onto the axial molecule, and side chains having OH groups introduced into the cyclic molecules, 1 mol % or more to less than 100 mol % of OH groups in the side chains are modified with a compound having a radical-polymerizable group, (B) a photochromic compound, and (C) a polymerizable monomer other than the (A) polyrotaxane monomer.