Abstract: This invention provides a modified liquid epoxy resin having a low viscosity and a high performance, which is obtained by reacting a mixture of a bisphenol and a phenol aralkyl resin with an epiholohydrin. The bisphenol is preferable to be bisphenol F and is further preferable to have a bifunctional form purity as detected by gel permeation chromatography at UV 254 nm of not less than 95% by area in view of the fluidity. Moreover, the mixture of bisphenol and the phenol aralkyl resin is preferable to have a ratio of the phenol aralkyl resin of 10-70% by mass.

Abstract: A phenolic compound which can be obtained by reacting the compound of the formula (1): wherein R1 groups are each independently present and represent a hydrogen atom etc. with the formula (6): wherein R4 groups are each independently present and represent a hydrogen atom etc.; and k represents the number of R4 groups and is an integer of 0 to 4 and an epoxy resin which can be obtained by reacting the phenolic compound with an epihalohydrin are excellent in solvent solubility and also of which cured product has an excellent thermal conductance.

Abstract: A phenol aralkyl type phenolic resin represented by the general formula (1), wherein the total content of the compounds represented by formulae (2) to (4) is 58 to 92% as determined by GPC and the contents of the compounds represented by formulae (2) to (4) as determined by HPLC satisfy the following relationship: 0.60?(2a+b)/(2a+2b+2c)?0.90 wherein a is the content of the compound of formula (2); b is the content of the compound of formula (3); and c is the content of the compound of formula (4).

Abstract: This invention provides a modified liquid epoxy resin having a low viscosity and a high performance, which is obtained by reacting a mixture of a bisphenol and a phenol aralkyl resin with an epiholohydrin. The bisphenol is preferable to be bisphenol F and is further preferable to have a bifunctional form purity as detected by gel permeation chromatography at UV 254 nm of not less than 95% by area in view of the fluidity. Moreover, the mixture of bisphenol and the phenol aralkyl resin is preferable to have a ratio of the phenol aralkyl resin of 10-70% by mass.

Abstract: A phenol aralkyl type phenolic resin represented by the general formula (1), wherein the total content of the compounds represented by formulae (2) to (4) is 58 to 92% as determined by GPC and the contents of the compounds represented by formulae (2) to (4) as determined by HPLC satisfy the following relationship: 0.60?(2a+b)/(2a+2b+2c)?0.90 wherein a is the content of the compound of formula (2); b is the content of the compound of formula (3); and c is the content of the compound of formula (4).

Abstract: An object of the present invention is to provide a multifunctional epoxy resin that is in a liquid state and that has a multifunctional structure. The multifunctional epoxy resin can be used as a reactive diluent and also used for a wide range of applications such as a molding material, a casting material, a laminating material, a paint, an adhesive, and a resist. The epoxy resin of the present invention is produced by glycidylation of dipentaerythritol represented by formula (1): wherein, in the number of moles of a hexafunctional compound (HG) and the number of moles of a pentafunctional compound (LG) in the epoxy resin, the ratio of the number of moles of (HG) to the total number of moles of (HG) and (LG), namely HG/(HG+LG), is in the range of 0.05 to 0.9.

Abstract: An object of the present invention is to provide an epoxy resin exhibiting superior heat resistance, dielectric properties, water resistance, and workability, a resin composition containing the epoxy resin, and a prepreg and a laminated plate. The epoxy resin of the invention is expressed by the following formula. (In the formula, R represents a hydrocarbon group having a carbon number of 1 to 4. m Represents an integer of 1 to 4 and when m is 2 to 4, R's may be the same or different. n Represents a positive number of 1 to 6 on average.) The epoxy resin composition of the invention contains the epoxy resin of the invention and a curing agent.

Abstract: It is an object of the present invention, with respect to a phenol aralkyl type epoxy resin, to suppress any crystal precipitation, improve the quality manageability and operation efficiency at composition production and enhance the properties, including heat resistance, thereof. It is also intended to provide a resin composition that even when stored in the form of a varnish for a prolonged period of time, is resistant to crystal precipitation, excelling in storage stability and operation efficiency, and that gives a hardening product of low dielectric constant and low dielectric tangent excelling in heat resistance, water resistance and flame retardance. There is provided an epoxy resin characterized by comprising a phenol aralkyl type epoxy resin in which a content (an area % measured by gel permeation chromatography) of a bifunctional compound is 20% or less, and provided a resin composition obtained therefrom.