JPS60226442A - Cement admixture - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides mortar tf1" for undercoating concrete, etc.
Concerning cement admixtures for forming.

<Prior art> The surface (base) of concrete structures is often uneven and does not look good, so mortar is often applied to make the surface smooth and beautiful.

Since the work of applying Molcle is complicated, an admixture for undercoat for construction was proposed in Japanese Patent Publication No. 52-29351 to completely improve this problem. This base coating admixture is mainly composed of foamed polystyrene powder with crushed grooves on the surface, and a small amount of binder, caking, and water-retaining powder. Mixed with basecoat mole
A record is created.

When the mortar is applied to the base, as it dries, the styrofoam powder in the mortar rises to the surface of the mortar, making the surface uneven. Even if the pricking work is omitted, the topcoat vvi
- It can be easily applied to the undercoated surface, improving mortar application work.

<Problems to be Solved by the Invention> In order for the undercoating molcle to adhere well to the base, it is required that the molcle does not dry until the hydration reaction of the cement is completed. It is desirable that the material has high water retention. The above-mentioned admixture retains water and has water retention properties mainly through the crushed grooves on the surface of the expanded polystyrene powder, but the crushed grooves do not retain enough water due to the surface tension of the water. They tend to be difficult to retain and lack water retention, and therefore, there are cases where the adhesion to the substrate is reduced, and measures to prevent moisture drying have often been taken. In addition, since the admixture is mainly made of expanded polystyrene powder, the strength of the molcle itself is low, and
It has poor heat resistance and fire resistance, and also has the disadvantage that the trowel does not slip easily when applying mortar, resulting in poor workability.

<Means for solving the problems> The present invention has been made in view of the above problems, and includes:
The object of the present invention is to provide a cement admixture that has good water retention properties, good adhesion to the base material, and workability, and can also improve the strength of the mortar itself and impart flame retardancy. The main materials are crushed pieces of foamed resin containing at least foamed polyvinyl chloride, and crushed pieces of a synthetic resin sheet with water-retaining paper pasted on the back side, and short fibers,
It is characterized by containing a small amount of thickener and adhesive.

<Function> Since the admixture of the present invention contains as a main material crushed pieces of a synthetic resin sheet with water-absorbing paper with good water-retaining properties pasted on the back side, the admixture of the present invention prevents the cement from drying during mortar drying. Since it can effectively prevent mortar from drying until the aqueous phase reaction is completed, why not use mortar as a base? 11 It can be applied easily. Moreover, since the paper part containing moisture is attached to a synthetic resin layer that does not expand or contract even when drying, the thin pieces of the synthetic resin sheet in the mortar will not shift during drying, and the mortar will not be easily coated. It does not reduce sexiness.

Further, since the synthetic resin sheet is crushed into flakes without the use of any special crushing means, the trowel can easily slide during mortar application work, and the workability is excellent. In addition, as crushed pieces of foamed vinyl chloride are necessary to form crushed pieces of foamed resin that stand out on the surface of the mortar after drying and form an uneven surface, it contributes to the formation of unevenness on the surface of the mortar and is flame retardant. can be applied and the strength of the mortar can be improved. Furthermore, by adding small amounts of short fibers, thickeners, and adhesives in addition to the above-mentioned main materials, cracking of the molcle can be prevented, and workability and applicability can be improved.

<Example> Examples of the present invention will be described in detail below.

The admixture of the present invention consists of crushed pieces of a foamed resin containing at least foamed polyvinyl chloride, crushed pieces of a synthetic resin sheet with water-containing paper attached to the back surface, and metal raw material.

The crushed pieces of foamed resin are blended to form irregularities on the surface of the mortar when it dries, so that the top coat mortar can be applied well.The material used for this is foamed polystyrene, foamed polyethylene, foamed polyurethane, etc. You can freely choose from. However, foamed polyvinyl chloride having self-extinguishing properties is necessarily added to these to improve the strength of the molcle and impart flame retardance. As a foam material other than foamed polyvinyl chloride, foamed polystyrene is preferred from the viewpoint of weight reduction and cost, but it is needless to say that the material is not limited to this.

The size of the crushed pieces of foamed resin is preferably 2 to 4 in order to suitably apply the top coat. Also,
Its shape is not particularly limited, and there is no need to form grooves for moisture retention on its surface.

The other main material, the shredded synthetic resin sheet, is a decorative sheet that is usually used by pasting it on walls or floors, and the synthetic resin sheet with water-containing paper pasted on the back side is crushed. The sheet to be used can be made of steel or scrap, which is advantageous in terms of cost. tfN, the form of the resin is:
Regardless of whether it is foamed or not, its material is not specified, but flame-retardant vinyl chloride is suitable. The size of the crushed pieces is preferably about 2 to 6 tm because they are easy to crush and the paper portion is difficult to peel off from the coating resin.

Since the paper part of the crushed pieces has good water retention, the cement in the mortar effectively prevents drying of the mortar until it is completely cured after 6 tons of hydration, and the dryout C.
It is possible to prevent the occurrence of peeling of the base material and the molcle due to poor adhesion. In addition, since the paper part has a synthetic resin layer attached to it, it will not expand or contract due to drying of moisture, and there is no need to worry about misalignment during the hardening of the cement, which will reduce the adhesion of mortar. There is no.

Furthermore, since the crushed pieces are usually in the form of flakes, the trowel can easily slide during mortar application work, resulting in excellent workability.

In addition to the main ingredients mentioned above, small amounts of short fibers, thickeners, and adhesives are blended.

The short fibers serve as a binder and are made of a material that is not affected by alkalinity, such as polyester fiber, rayon fiber, or cotton, and have a length of 10 to 20 U+. Furthermore, that shape! ! It is not limited to the IVi thread form, but may be in the form of a single fiber.

Thickeners are added to impart appropriate viscosity to mortar and improve workability, and adhesives are added as an auxiliary agent to further improve the adhesion of mortar.

Next, specific examples will be listed and explained.

Ill For one bag of cement (40 to 9), mix one bag of admixtures of Example 1.2 of the present invention and comparative examples (65 to 701) and water C (approximately 251) of the composition shown in Table 1, and apply the undercoat. I created the entire Molcle for use.

Table 1 Notes 1. In addition, each bag of admixture contains approximately 25P of Polyester I short fibers, approximately 80P each of thickener and adhesive.

(2) Water Retention Test Using the mortar No. 111 above, water retention was investigated using a water retention testing device specified in JISA6904 (Setsukou Plasque).

The suction force was 50 m of mercury, the water ratio of the molcle at suction times of 2 minutes and 10 minutes was determined, and the water retention rate was calculated using the following formula. The results are shown in Table 2.

Table 2 From Table 2, Examples 1 and 2 of the present invention have the following characteristics compared to the comparative example:
It can be seen that the water retention property is nearly 1.5 times better.

(31 Mortar Strength Test The above Il+ morkle was placed on a slate board +Ocmφ×
After applying it to a disk shape with a thickness of 5 cm and drying and hardening, a tensile test jig of lOc+wO was glued to the top surface using an epoxy adhesive, and the jig was pulled to obtain a tensile strength of 57 cd).
and the fracture site was investigated. The results are shown in Table 5.

Table 6 Although the upper surface of the slate did not peel off in either the example or the comparative example, Table 6 shows that the strength of the example of the present invention was approximately 1.4 times higher than that of the comparative example. I understand.

<Effects of the Invention> As described above, since the admixture of the present invention has extremely excellent water retention, it can greatly improve the adhesion between the mortar and the base, and also improve the strength of the mortar. Furthermore, it is possible to improve coating workability and impart flame retardancy.

As described above, the present invention has excellent performance that cannot be found in other admixtures, and its utility value as an admixture for forming a molcle for undercoating is significant.

Claims (1)

[Claims] 1. Crushed pieces of foamed resin containing at least foamed polyvinyl chloride and crushed pieces of a synthetic resin sheet with a hydrous gold paper pasted on the back are used as raw materials, and short fibers, a thickening agent, A cement admixture characterized by containing a small amount of adhesive.