Abstract: Provided are a cement mortar additive for extrusion molding, a cement mortar for extrusion molding, and an extrusion-molded product. The disclosed cement mortar additive for extrusion molding includes hydrogelated cellulose ether.

Abstract: Provided are a cement mortar additive for extrusion molding, a cement mortar for extrusion molding, and an extrusion-molded product. The disclosed cement mortar additive for extrusion molding includes hydrogelated cellulose ether.

Abstract: The present invention relates to a method of manufacturing ultra-low viscosity hydroxyalkyl cellulose through a partial neutralization method, and the method includes: reacting cellulose with an alkalizing agent to obtain alkalized cellulose; reacting the alkalized cellulose with an etherifying agent to obtain hydroxyalkyl cellulose; performing first neutralization of the hydroxyalkyl cellulose; decomposing the hydroxyalkyl cellulose by using hydrogen peroxide; and performing second neutralization of the hydroxyalkyl cellulose. Through the aforementioned method, ultra-low viscosity hydroxyalkyl cellulose can be manufactured while preventing a process problem, such as swelling, which may occur through the decomposition of an acid treatment.

Abstract: The present invention relates to a method of manufacturing ultra-low viscosity hydroxyalkyl cellulose through a partial neutralization method, and the method includes: reacting cellulose with an alkalizing agent to obtain alkalized cellulose; reacting the alkalized cellulose with an etherifying agent to obtain hydroxyalkyl cellulose; performing first neutralization of the hydroxyalkyl cellulose; decomposing the hydroxyalkyl cellulose by using hydrogen peroxide; and performing second neutralization of the hydroxyalkyl cellulose. Through the aforementioned method, ultra-low viscosity hydroxyalkyl cellulose can be manufactured while preventing a process problem, such as swelling, which may occur through the decomposition of an acid treatment.

Abstract: A focus control device for a beam projector allows the focus of a lens assembly to be finely and easily controlled. The focus control device includes: a control member rotatably mounted on the beam projector for controlling the focus of a lens assembly; a rotary eccentric member provided in the control member, the rotary eccentric member having a control axis eccentric to the rotary axis of the control member, and being rotated while depicting an elliptical trace in response to the rotation of the control member; a focus guide member provided in the rotary eccentric member, the focus guide member allowing the lens assembly to be moved rectilinearly in the direction of an optical axis in response to the rotation of the control member; and an actuating member provided in the lens assembly and coupled to the focus guide member, the actuating member moving the lens assembly in the direction of the optical axis in response to the movement of the focus guide member.

Abstract: A focus control device for a beam projector allows the focus of a lens assembly to be finely and easily controlled. The focus control device includes: a control member rotatably mounted on the beam projector for controlling the focus of a lens assembly; a rotary eccentric member provided in the control member, the rotary eccentric member having a control axis eccentric to the rotary axis of the control member, and being rotated while depicting an elliptical trace in response to the rotation of the control member; a focus guide member provided in the rotary eccentric member, the focus guide member allowing the lens assembly to be moved rectilinearly in the direction of an optical axis in response to the rotation of the control member; and an actuating member provided in the lens assembly and coupled to the focus guide member, the actuating member moving the lens assembly in the direction of the optical axis in response to the movement of the focus guide member.