JPS62187150A - Mortar undercoating material for construction - 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 (Field of Industrial Application) The present invention provides a mortar base material for construction, which is formed by adding a shrinkage reducing agent for cement and a mortar additive consisting of rubber latex or a synthetic resin emulsion to a mortar mixture. Regarding.

(Prior art) Conventionally, as a base material for mortar construction of wooden buildings, a construction mortar base material in which a cement mortar coating layer is formed on a wooden plate-like substrate has been devised, and it has been used as a labor-saving component in the wet method 1 method. It is widely used.

This base material is a base material that can be used by omitting lath base material boarding, felt covering, lath wire meshing, and applying an undercoat and only applying a topcoat, and can sufficiently save labor in construction.

Furthermore, if a cement mortar coating layer containing foamed synthetic resin particles is formed on a wooden plate-like substrate, the thickness of the cement mortar coating layer itself can be increased, which is superior in terms of weight reduction and workability. It is also used as a base material that is close to dry.

(Problem to be Solved by the Invention) However, in such a base material, even after it is installed between structural members, due to drying shrinkage of the applied top coat cement mortar layer over time, the structural member cannot be used as a fulcrum. A new problem has arisen in that cracks occur not only at the butt joints between base materials but also along the structural members.

Furthermore, as a result of the formation of a coating interface between the top coat cement mortar coating layer and the base material, external impact forces tend to concentrate on this interface, resulting in a peeling phenomenon at the interface.

On the other hand, even if the above-mentioned peeling phenomenon does not occur, the finishing material is applied directly to the base material, which has the advantage of increasing the overall strength of the exterior wall material. Another drawback was that the effect of preventing cracks could not be expected to be very high.

In order to solve these problems with base materials, warpage and deflection can be prevented by making the plate-like base material itself thicker, by placing it horizontally between structural members, or by reducing the spacing between structural members. In addition, external wall finishing materials such as cement mortar that are coated on the base material have been selected to have minimal drying shrinkage.

However, in both cases, labor and material costs are required, and at the same time, there are problems in that the expected effects are not obtained.

(Means and effects for solving the problems) Therefore, the present invention provides a mortar mixture that is applied to a plate-shaped Omurakami plate and includes a shrinkage reducing agent for cement and a rubber latex or synthetic resin emulsion for mixing with cement. This method solves the above-mentioned problems by adding an admixture to form a mortar base material.

Hereinafter, the architectural mortar base material of the present invention will be explained in detail.

First, as the base material used in the present invention, as shown in the figure, a waterproof adhesive layer 2 is provided on a plate-like base material l, and the upper surface of this waterproof adhesive layer 2 is made of a lightweight aggregate 31 and a hydraulic substance 32. Mortar mixture 3 is applied. As the plate-like base material l, a wood substrate such as plywood, hardboard, particle board, or an inorganic board material having a size of about 4 to 12 cm is usually used.

The waterproof adhesive layer 2 is formed to prevent rainwater and excess water from curing the mortar from entering from the outer surface and to improve adhesion to the mortar mixture, and is usually used in coating film waterproofing methods. Resins with high adhesive properties, such as synthetic resins such as acrylic styrene and ethylene vinyl acetate, butyl rubber,
A synthetic rubber resin such as SBRlMBR is used. This waterproof adhesive layer 2 is formed to a desired thickness using a coating device such as a roll coater.

Further, as the lightweight aggregate 31, fine aggregates such as synthetic resin foam particles and pearlite are used, and these lightweight aggregates 31 are mixed with a hydraulic substance 32 made of cement or the like, water, and mortar additives to form a mortar mixture. 3, and the mortar mixture 3 is coated onto the plate-like base material 1 to a desired thickness using a roll coater or the like.

Then apply exterior cement mortar to the top surface.

Incidentally, the above-mentioned base material can be manufactured by the method disclosed in Japanese Patent Application No. 102729/1983, which is already pending by the applicant.

Aggregate 31. The mortar additive 4 added to the mortar mixture 3 consisting of a hydraulic substance 32 and water is composed of a shrinkage reducing agent 5 and a synthetic rubber latex 6 or a synthetic resin emulsion 7.

The shrinkage reducing agent 5 used is one that acts to reduce the surface tension inside the mortar during drying shrinkage, and is usually one or more compounds represented by the general formula RO(AO)nH. Consists of a mixture.

In the above formula, R is an alkyl group having 1 to 4 carbon atoms, A is one or two alkylene groups having 2 to 3 carbon atoms, and n is 1.
~lO, and polyoxyethylene alkylphenol ether and lower alcohol alkylene oxide adducts are preferred. Further, as the synthetic rubber latex 6, butyl rubber, SBR5MBR, etc. are used, and as the synthetic resin emulsion 7, resins such as acrylic styrene type and ethylene vinyl acetate type are used.

On the other hand, the shrinkage reducing agent 5 and the synthetic rubber latex 6 or
The mixing ratio of the synthetic resin emulsion 7 is in the range of 50 to 100 parts by weight of the shrinkage reducing agent to 100 parts (non-volatile content) of the synthetic rubber latex or synthetic resin emulsion.

When producing the mortar additive 4 comprising the shrinkage reducing agent 5 and the synthetic rubber latex 6 or synthetic resin emulsion 7, a predetermined amount of the rubber latex or resin emulsion can be easily adjusted by stirring and mixing.

The amount of these mortar additives 4 added to the mortar mixture 3 consisting of cement, synthetic resin foam particles, and water formed on the wood plate-like base material l depends on the thickness of the mortar mixture 3, but is usually 100% of the mortar mixture 3. It is added within the range of 5 to 15 parts by weight.

At the time of addition, a uniform mixture layer can be obtained by stirring and mixing the cement, foamed synthetic resin particles, and water in a mortar mixer in a predetermined amount, then adding the mortar additive, and further stirring and mixing.

Next, the mortar mixture containing additives for mortar obtained by the above stirring and mixing is applied to a predetermined thickness by a roll coater or the like on a plate-shaped base plate, and cement mortar as an exterior material is applied to the top surface to a desired thickness. Coat.

Incidentally, if the amount added is less than the above range, the effect of reducing shrinkage of cement mortar will not be sufficient.

If the amount exceeds the above range, the adhesion between the mortar mixture layer and cement mortar will be poor, resulting in problems such as poor plastering workability and peeling of the cement mortar.

In the above explanation, a shrinkage reducing agent and additives consisting of synthetic rubber latex or synthetic resin emulsion were added to a mortar mixture as an undercoat consisting of cement, foamed synthetic resin particles, and water. It is also a time to add.

(Effects of the invention) As described above, the architectural mortar base material of the present invention has the following properties:
Since a mortar additive consisting of synthetic rubber latex or synthetic resin emulsion and shrinkage reducing agent is added, an extremely strong cement layer is formed, and plastering properties are also good, and cracks do not occur in the cement mortar. It is an extremely effective mortar base material for construction, both technically and economically, with a high prevention effect.

(Example) Next, one embodiment of the present invention will be described.

Example 1 3 parts of expanded polystyrene particles and Portland cement were placed on plywood with a thickness of 6 mm that had been treated with antiseptic and insect repellent treatment.
For a mortar mixture consisting of 100 parts of MBR synthetic rubber latex and 20 parts of water, an additive for mortar consisting of 100 parts of an ethylene oxide adduct of a lower alcohol (trade name: Tetraguard S3 (manufactured by Nippon Cement Co., Ltd.) J). 20 parts were added and mixed by stirring, and the resulting mixture was coated with a roll coater to a thickness of about 6 cm and dried. Next, 12 mm of exterior cement mortar having a normal composition (Portland cement 1:sand 3) was applied with a trowel, and an exterior finish with good coating properties and almost no cracking was obtained.

[Brief explanation of drawings]

The figure is a schematic cross-sectional view of a mortar base material for construction. l...Plate base material, 2...Waterproof adhesive layer. 3...Mortar mixture, 31...Lightweight aggregate. 32...Hydraulic substance, 4...Additive for mortar. 5... Shrinkage reducing agent, 6... Synthetic rubber latex. 7...Synthetic resin emulsion.

Claims (1)

[Claims] (1) In a mortar base material in which a mortar mixture is applied on a plate-like base material, the mortar mixture has RO(AO)n
A mortar base material for construction, to which a cement shrinkage reducing agent consisting of one type or a mixture of two or more compounds represented by the general formula H and a mortar additive consisting of rubber latex or a synthetic resin emulsion are added.