JPH0674629B2 - Mortar base tape or sheet - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an improvement of a mortar base tape or sheet.

Structure of Conventional Example and Its Problems As a mortar base tape or sheet, it is known that an asphalt composition is applied from the back surface of a non-woven fabric and the composition is impregnated to a thickness of about half of the non-woven fabric. Is used as an adhesive to the base, and the upper half of the asphalt composition not impregnated is used for impregnation and fixing of coating mortar.

However, in this mortar base tape or sheet, since the asphalt composition is used as the adhesive, it is difficult to adhere to the base in cold regions, and cracking easily occurs. On the other hand, in warm regions, the workability is deteriorated due to the stickiness of the asphalt composition and surrounding pollution is likely to occur.

By the way, if a pressure-sensitive adhesive such as an unvulcanized butyl rubber composition is used as an adhesive, the above disadvantages can be eliminated. However, in mortar coating, there is a problem that cracking is likely to occur due to curing shrinkage at the time of curing, and in the above mortar base tape or sheet, simply replacing the asphalt composition with an adhesive rubber composition results in the above. The problem cannot be resolved.

OBJECT OF THE INVENTION It is an object of the present invention to prevent the occurrence of cracks during the curing of the mortar and strengthen the adhesion with the mortar by utilizing the elasticity of the adhesive rubber composition.

Structure of the Invention That is, the mortar base tape or sheet according to the present invention is characterized in that the adhesive rubber composition is coated from the back surface of the nonwoven fabric, and the composition is partially penetrated to the nonwoven fabric surface. Is.

Description of Embodiments The present invention will be described below with reference to the drawings.

In FIG. 1, 1 is a nonwoven fabric. No. 2 is an adhesive rubber composition which is applied from the back side of the non-woven fabric and is partially permeated to the non-woven fabric surface as shown by 20, ... in FIG. 2 (top view of FIG. 11). 3 is a separate tape.

FIG. 3 shows the use state of the tape of the present invention. The tape of the present invention is adhesively fixed to the mortar base plate 4 in the adhesive rubber composition layer 21, and the mortar 5 is applied on the surface of the tape. Mortar is impregnated in the rubber composition non-penetrating portions 10, ....

After applying the mortar, the applied layer is dried and hardened over time from the surface side, accompanied by hardening shrinkage. Thus, this state can be approximated to a state in which the upper half first undergoes curing shrinkage, and then the lower half undergoes curing shrinkage.When the upper half is cured, the lower half becomes uncured and soft. Therefore, there is almost no risk of cracking due to curing shrinkage of the upper half. However, when the lower half portion is cured and contracted, the upper half portion is already hardened, so that stress is generated, and if this stress becomes large, cracking cannot be avoided.

Now, in FIG. 3, the upper half A is already hardened, its thickness is t ₁ , Young's modulus is E _1, and in this state, the lower half B of the thickness t ₂ is hardened with the shrinkage α. If the Young's modulus after contraction is E ₂ , the compressive stress δ acting on the already hardened upper half A
Is Is.

Thus, the Young's modulus E ₂ (length direction) in the lower half B is equivalent to the Young's modulus of the structure in which the cured mortar and the adhesive rubber composition are combined in series, and the adhesive rubber Equivalent Young's modulus E ₂
Is approximately B'Eo with respect to the Young's modulus Eo of the adhesive rubber composition. Since the adhesive rubber composition is an elastic body having a low Young's modulus, E _{2 in} the first equation can be remarkably reduced, and the compressive stress δ acting on the upper half can be extremely reduced. Therefore, cracking of the upper half mortar cured product can be well prevented.

In the above, if the ratio B'of the adhesive rubber composition impregnated into the nonwoven fabric in the volume of the nonwoven fabric is increased, the above-mentioned equivalent Young's modulus E ₂ can be reduced by that much, and cracking of the upper half mortar cured product can be prevented. This is advantageous, but the rate at which the non-woven fabric can be impregnated with mortar (10 in FIG. 3) is small, which is disadvantageous in fixing mortar. Therefore, the above B '
Is suitable for 10-80% of the surface area.

In the present invention, the non-woven fabric may be organic or inorganic, and depending on the application, may be made of durable polyester, polypropylene, or polyethylene, and if necessary, in order to improve water absorption. What was impregnated with a surfactant may be used, or it may be pressed or embossed.

In the present invention, as the adhesive rubber composition, those containing butyl rubber, isoprene-isobutylene copolymer rubber, chloroprene rubber, styrene butadiene rubber, synthetic rubber such as EPT rubber, butyl recycled rubber and natural rubber as the main components are used. . In addition, polyethylene, polypropylene and EVA are added to the above rubbers to prevent dripping and to further increase the adhesiveness.
A thermoplastic resin, an inorganic filler such as heavy carbon, titanium white, and sulfur, and a synthetic asphalt such as natural asphalt or blown asphalt may be appropriately mixed. Further, an organic rubber chemical such as a rubber anti-aging agent, a tackifying resin, a softening agent and the like may be appropriately added.

The mortar base tape or sheet according to the present invention can be manufactured, for example, as follows.

The unvulcanized butyl rubber composition that has been sufficiently kneaded in advance with a Banbury mixer or the like is supplied to a calendar roll, and this is applied to the nonwoven fabric fed from the feeding roll, and this is applied to the release paper fed from the roll on the roll. In addition, in this case, in order to permeate the rubber composition into the non-woven fabric to the non-woven fabric surface in a dotted manner, the rubber composition is pressure-bonded by using a coating roll having a roll-shaped dotted pattern to be permeated. Alternatively, after applying the rubber composition, an embossing roll may be used as a roll to be bonded to the release paper. Alternatively, an embossing roll may be separately installed between the coating roll and the laminating roll. Alternatively, the above rubber composition alone or a tape-shaped one having a woven cloth made of organic and inorganic materials such as garment cloth and the like as a central base material may be pasted with a non-woven fabric by a roll while heating to be infiltrated. . As another method, a non-woven fabric having a thin and thin pattern is selected, and an adhesive rubber composition is applied from the back surface of the non-woven fabric, or after the application, the whole is uniformly pressed to form a thin portion. May be permeated only.

Next, examples of the present invention will be described.

Example 1 The composition of the butyl rubber composition used is as follows.

Butyl rubber 100 parts by weight Butyl recycled rubber 10 〃 SBR 20 〃 Tatsuki fire 20 〃 Carbon black 15 〃 Stearic acid 1 〃 Zinc oxide 3 〃 Asphalt 5 〃 DOP 2 〃 Anti-aging agent 0.3 〃 Heavy coal 80 〃 Heavy coal Knead thoroughly for about 30 minutes, supply this mixture to a calendar roll heated to 50 to 120 ° C, and use an embossing roll with a convex surface of 1 m / m height of 50% on the coating roll to make a polyester nonwoven fabric of 1 m / m thickness. The butyl rubber composition was applied to a thickness of 2 m / m, and the butyl rubber composition was permeated to 50% of the total area of the nonwoven fabric surface.

Example 2 A tape having the butyl rubber composition of Example 1 above in the form of a sheet having a thickness of 1.5 m / m was laminated on an embossing roll having a convex surface of 40% heated at 50 ° to 60 ° C. and a polyester having a thickness of 1 m / m. Laminated with non-woven fabric.

EFFECT OF THE INVENTION The mortar base tapes obtained in Examples 1 and 2 above were each adhered and fixed on the base plate of wood plywood, and then mortar was applied and dried and cured, and no crack was generated. .

Also, the adhesive strength of the mortar base tape to the base plate and the mortar itself was measured by a 180-degree peel test (temperature: 0 ℃ to 50 ℃).
℃), it was about 5.0kg / 20mm width for the plywood and about 100.0kg / 20mm width for the mortar, both of which have caused cohesive failure phenomenon, and mortar peeling and interface peeling from the plywood occurred. I didn't.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a mortar base tape according to the present invention, FIG. 2 is a top view of FIG. 1, and FIG. 3 is an explanatory view showing a usage state of the tape of the present invention. In the figure, 1 is a nonwoven fabric and 2 is an adhesive butyl rubber composition.

Claims (1)

[Claims] 1. A mortar base tape or sheet comprising an adhesive rubber composition coated on the back surface of a non-woven fabric, the composition being partially penetrated to the surface of the non-woven fabric.