The present application discloses an allyl-type flame-retardant prepolymer, a resin composition, a composite resin, a prepreg, and a laminate. The allyl-type flame-retardant prepolymer provided in the present application is prepared by pre-polymerization of an allyl-type benzoxazine compound and an allyl-type phosphorous compound in a mass part ratio of 100:(20 to 80).

A method for preparing a cellulose dispersion includes oxidizing cellulose; preparing cellulose nanofibers by defibrating the oxidized cellulose; and adding a water-soluble polymer and inorganic particles to the dispersion containing the cellulose nanofibers.

[Object] To shorten the work time in the step of forming a water-insoluble resin layer having a recessed and projecting shape on a to-be-transferred body. [Solving Means] A transfer sheet (10) for forming a recessed and projecting shape includes: a water-soluble resin layer (20) that is formed of a water-soluble resin whose dissolving time in distilled water at 25 C. is 0.2 s/m or more and 1.0 s/m or less and includes recesses and projections on a first surface thereof; and a water-insoluble resin layer (30) that is stacked on the first surface.

A method for the construction of an improved tank base. A tank base is constructed for protection against accidental spills and/or leaks associated with a tank battery. The improved tank base comprises at least one part of a suitable substrate, which allows for the adhesion of an elastomer such as polyurea. Polyurea is preferably applied using a spray device which yields an average coverage of about 50-80 mils, and most preferably 60 mils. If more than one substrate is used, one or more substrates can be bound together with a fastening system. Once pressure is applied in the form of weight, the fastening system can be removed, resulting in an improved tank base having at least one seam and impervious to the fluid of the tank battery.

A method for the construction of an improved tank base. A tank base is constructed for protection against accidental spills and/or leaks associated with a tank battery. The improved tank base comprises at least one part of a suitable substrate, which allows for the adhesion of an elastomer such as polyurea. Polyurea is preferably applied using a spray device which yields an average coverage of about 50-80 mils, and most preferably 60 mils. If more than one substrate is used, one or more substrates can be bound together with a fastening system. Once pressure is applied in the form of weight, the fastening system can be removed, resulting in an improved tank base having at least one seam and impervious to the fluid of the tank battery.