JPS6131503A - Pavement material layer of urethane track and its 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] [Technical Field] The present invention relates to a paving material layer and a construction method for all-weather urethane tracks, and more specifically, the present invention relates to a paving material layer and a construction method for all-weather urethane tracks, and more specifically, the present invention relates to a paving material layer for all-weather urethane tracks and a construction method that does not cause problems such as peeling or blistering from the base material and has appropriate elasticity. The present invention relates to a paving material layer and a construction method for an improved all-weather urethane track that has high properties.

[Background technology]

When used as a base material such as cement concrete or asphalt concrete and then paved with urethane, it exhibits flexibility and elasticity, and this construction method is used for gymnasium floors and sports facilities such as tennis courts, track and field stadiums, and tracks. 'Among these uses, cement concrete is not used as the construction base for tracks in athletics stadiums, etc. due to problems such as joints and cracks, and asphalt concrete (hereinafter referred to as ``ASCON'') is mostly used. ing.

However, Ascon is sensitive to heat and water, and as a result, the urethane track tends to peel or bulge. Particularly in summer, when the air temperature is high, the surface temperature of the paved surface reaches as high as 60° C., which softens the ascon and reduces its strength, causing the ascon and the urethane to separate due to the tensile action of the urethane material. This peeling phenomenon is further aggravated when the ascon contains moisture from the base roadbed, as this evaporates and water vapor pressure acts on it. Conventional urethane pavement has many problems of this kind, and is a source of trouble for urethane tracks. If this peeling and blistering phenomenon is left untreated, the track itself will rise unevenly and the repulsive force will change, causing extremely dangerous accidents such as falls by athletes, and many stadiums do not repair these. The reality is that they are being chased by

On the other hand, although the urethane track material itself generally has elasticity, it has poor shock absorption properties, so it has the disadvantage of causing significant muscle fatigue. In order to improve shock absorption, methods have been proposed to reduce the hardness of urethane by making the crosslinking density of urethane sparser, or by adding unreacted liquid plasticizer or increasing the amount of cine. In addition, since the repulsion elasticity is significantly reduced, new problems such as insufficient repulsion force arise. As described above, existing construction methods have not taken effective measures to prevent urethane track peeling and blistering accidents, as well as to reduce muscle fatigue for athletes, and there has been a wide demand for immediate improvements. .

The inventors of the present invention have continued to conduct intensive research into ways to improve these drawbacks, and as a result, all the problems of the existing methods described above have been solved, and a urethane track with various excellent features as described below has been developed. The present invention was completed by discovering a paving material layer and its construction method.

[Purpose of the invention]

An object of the present invention is to provide a paving material layer for a urethane track that does not cause peeling or blistering from an ascon, and a method for constructing the same. Another object of the present invention is to provide a comfortable paving material layer for urethane tracks that causes less muscle fatigue and a method for constructing the same. Another object is to provide a track that is easy to record and a construction method thereof. Another object of the present invention is to provide a highly durable truck that does not undergo deterioration over many years, and a method for constructing the same. Another object is to provide a urethane track having a uniform thickness and a method for constructing the same. Furthermore, other objects and advantages will become apparent from the description below.

[Disclosure of the invention]

The above-mentioned purpose is to sequentially laminate a polymer cement paste layer containing a synthetic resin emulsion and Portland cement as main components, a primer layer, and a polyurethane layer containing foamed elastic rubber particles on the ascon surface, and the polyurethane layer is a part of the layer. is composed of urea bonds and three-dimensional cross-linking bonds, and a polymer cement paste layer, a primer layer, and a polyurethane layer are sequentially laminated on the paving material layer and ascon surface of the urethane track, and the polyurethane This is achieved by a urethane track construction method characterized by using a two-component curing liquid polyether urethane composition containing foamed elastic rubber particles as a layer.

The present invention will be explained in detail below.

Ascon, which is the base material for urethane trucks, is classified into coarse-grained, dense-grained, fine-grained, etc., depending on the type of aggregate such as crushed stone or sand, and the types of binding materials such as asphalt include straight asphalt and cutback asphalt. etc., but they are not particularly limited and may be appropriately selected and used depending on the purpose.

The commonly used Ascon is crushed stone of 150 to 45 Qmm.
After laying, a total of 7 pieces of coarse-grained ascon were applied to the base layer and dense-grained ascon was applied to the surface layer.
It is laid to a thickness of 0 to 90+n with a degree of compaction of 94% or more.

Polymer cement paste has a synthetic resin emulsion and Portland cement as its main components, and if necessary, silica sand or the like is mixed thereinto to form a paste. Then, when the surface of the ascon is covered with a polymer cement layer, the ascon's surface layer, which is vulnerable to heat, is strengthened and water that permeates and rises from the base is blocked. Additionally, the Portland cement mixed into the polymer cement paste helps improve durability, and the silica sand has the effect of correcting unevenness on the pavement surface.

As the synthetic resin emulsion, known latexes or emulsions are used, such as styrene-butadiene rubber (SBR) latex, natural rubber (NR) latex, chloroprene (CR) latex, acrylonitrile-butadiene rubber (NBR) latex, and vinyl acetate emulsion. , polyvinyl chloride emulsion, acrylic synthetic resin emulsion, epoxy synthetic resin emulsion, polyurethane emulsion, etc.
Styrene-butadiene rubber latex and acrylic synthetic resin emulsion are preferred. These may be used alone or in combination of two or more.

The blending amount of the synthetic resin emulsion and Portland cement varies depending on the use and purpose, but it is recommended that the amount of Portland cement be blended between 6 times and 15 times by weight based on the solid content of the synthetic resin emulsion. Common.

The water-based primer has the function of adhering not only to the polymer cement paste but also to the urethane material, in other words, to bond the polymer cement paste layer and the urethane layer, and a water-based primer is preferable. Examples of primers applicable to the present invention include emulsions or latexes of polyurethane, epoxy, acrylic ester copolymers, styrene-butadiene rubber, ethylene-vinyl acetate copolymers, polyamides, polyesters, etc. Preferably, and more preferably, epoxy resin is used. These primers may be used alone or in combination.

The liquid polyether urethane composition constituting the polyurethane layer includes (A) a polyether urethane prepolymer having free isocyanate groups obtained by addition-reacting a polyalkylene ether polyol having at least two hydroxyl groups and an aromatic polyisocyanate; (B) The main components are an aromatic diamine and a curing agent whose main components are the polyalkylene ether polyol.

The polyalkylene ether polyol of the present invention has two or more hydroxyl groups in one molecule and has an average molecular weight of 400 to 4,000, such as diols such as ethylene glycol and propylene glycol, or trimethylolpropane. , glycerin, triols such as hexanetriol, ethylene oxide, propylene oxide.

Examples include ring-opening addition polymerization of trimethylene oxide.

If the average molecular weight of this polyalkylene ether polyol is too small, the network of intermolecular crosslinks in the polyurethane track becomes too dense, making it difficult to obtain flexibility and elasticity as an elastic flooring material.On the other hand, if it is too large, the intermolecular crosslinks become too sparse. It tends to become too much and it is difficult to obtain sufficient strength.

The aromatic polyisocyanate in the present invention is one having two or more isocyanate groups in the molecule, such as 1,4-phenylene diisocyanate, 2,4-
Tolylene diisocyanate, 2゜6-tolylene diisocyanate, 1.5-naphthalene diisocyanate, 4.
4'-methylene-bis(phenylisocyanate)
, cumene-2,4-diisocyanate and these two
Examples include mixtures of more than one species.

The urethane prepolymer having three or more free isocyanate groups used in the two-component curing liquid polyether urethane composition has two or more isocyanate groups in a mixture with a polyol and diol having three or more hydroxyl groups. It is obtained by adding an aromatic polyisocyanate or an aromatic polyisocyanate having three or more diisocyanate groups to a diol. The ratio is 1 hydroxyl group of the polyalkylene ether polyol.
The amount of aromatic polyisocyanate is 1.2 to 2.
5 equivalents is preferred.

It is important that the above polyether type prepolymer contains a prepolymer having three or more free isocyanate groups, and a prepolymer having two free isocyanate groups alone is sufficiently cured (crosslinked). In addition, it is not possible to form the desired elastic polyurethane track.

It is also possible to use a mixture of a polyether-type urethane prepolymer having three or more free isocyanate groups and a polyether-type urethane prepolymer having two free isocyanate groups, but in this case, the mixing ratio of the former and the latter Preferably, the former is usually 30 to 80% by weight and the latter 20 to 70% by weight.

Furthermore, a prepolymer prepared by adding an aromatic polyisocyanate to a polyester polyol has poor alkali resistance. The curing agent mixed with the prepolymer derived from the above polyalkylene ether polyol is a mixture of aromatic diamine and the above polyalkylene ether polyol in an appropriate ratio. In particular, when polyalkylene ether polyol is used alone, both physical properties and durability are insufficient for use in trucks. It is important that the paving material layer of the urethane track of the present invention has not only urethane bonds but also urea bonds in its structure.

Preferred examples of the aromatic diamine include methylene bichloride orthochloroaniline, 2,2'-dichlorobenzidine, and the like. As the polyalkylene ether polyol used in combination with these, the polyalkylene ether polyol used for forming the prepolymer described above can be used.

The amount of aromatic diamine and polyalkylene ether polyol to be mixed is 0.7 to 1.0% of the active hydrogen atom per equivalent of free incyanate group in the prepolymer.
The ratio of 2 equivalents, i.e. (NH2+OH)/NGO=
A value of 0.7 to 1.2 is appropriate.

When the amount is less than 0.7 equivalents, the urethane tracks formed tend to foam and the smoothness decreases, and when it is more than 1 or 2 equivalents, the surface adhesion becomes significant and the physical properties deteriorate.

In addition, this two-component curing liquid polyether urethane composition may contain commonly used inorganic fillers such as titanium oxide, talc, and calcium carbonate, antioxidants (stabilizers), and Bengara, as necessary. Pigments or organometallic compound catalysts such as stannath octoate and dibutyltin silaureide can be used in combination.

As mentioned above, this urethane composition consists of a urethane prepolymer containing active isocyanate groups (Part A), a curing agent (Part B) consisting of an aromatic polyamine, a polyether polyol, and, if necessary, an inorganic filler and others. .

Part A and Part B are usually mixed in a weight ratio of 1:1 or 1:2 using an electric stirrer to react and cure. The foamed elastic rubber particles to be blended during this mixing include diene-based synthetic rubbers such as natural rubber, styrene-butadiene rubber, chloroprene rubber, butyl rubber, and nitrile-butadiene rubber, as well as ethylene vinyl acetate, vinyl chloride, polyurethane rubber, etc. Examples include granular rubber foams such as synthetic rubber, among which styrene-butadiene rubber and polyurethane rubber are preferred. These rubber particles are preferably granular rubber having a particle size in the range of 4 to 5 mesh.

The amount of these rubber particles added to the urethane composition is preferably 5 to 20 parts. The foamed elastic rubber particles contained in this polyurethane layer have a heat insulating effect, suppress heat conduction from the urethane surface to the ascon layer and thermal softening of the ascon, and counteract the tensile force caused by thermal expansion of the urethane track. In addition to preventing peeling and blistering accidents from the ascon, it also exhibits excellent effects such as absorbing impact from the track surface.

The paving material layer of the urethane track of the present invention having the above structure can be easily mixed and applied at room temperature.

The urethane track of the present invention is made of, for example, a crushed stone layer (thickness 15
0~300mm) with 30 pieces of coarse grain or dense grain ascon.
After coating the primer to a thickness of ~90 mm, a urethane composition containing the foamed elastic rubber particles of the present invention is applied as a urethane base layer (4 to 23 mm thick), and after curing, a urethane topping is applied, etc. It will be constructed by. The running track is usually finished with a thickness of 13 parts. Additionally, course line painting can be done if necessary after construction.

〔Effect of the invention〕

The urethane track according to the present invention obtained by the construction as described above has the following numerous advantages, and is a new and useful track that has comfortable elasticity and high durability that eliminates all the drawbacks of conventional tracks. .

1) It has rich shock absorption properties and reduces muscle fatigue in runners.

2) Excellent usability and easy running.

3) High kick repulsion force makes it easy to record.

4) Due to the heat insulation effect, there is little heat conduction to the underlying ascon, suppressing the softening and flashing phenomenon of the ascon, and preventing urethane track blistering accidents.

5) In order to suppress fluidity during track material construction, it does not flow unnecessarily even if there is a slope, and maintains a uniform thickness from 11 to 8 courses.

In addition, as a result of long-term tests (one year), the urethane track according to the present invention clearly has better physical properties and durability than the paving material layer of conventional urethane tracks, and has excellent shock absorption and recording performance. It was confirmed that no blistering or peeling accidents occurred from the Ascon base.

Regarding the latter, it is an accident that has a high occurrence rate, especially in countries like Japan, which have a lot of rainfall and high temperatures, so it would be extremely useful to solve this problem.

EXAMPLES The present invention will be described in more detail below with reference to Examples.

[Example 1] As component A of a two-component curing liquid polyether urethane composition, an excess of tolylene diisocyanate (
A branched polyether-type urethane prepolymer having a terminal isocyanate group content of 4.2% was obtained by reacting the prepolymer with 2,4-polymer/2,6-polymer (80/20) by a conventional method. -8 parts of methylenebisorthochloroaniline (0,6
Part 1-) 30 parts (0.3 equivalents) of polyoxypropylene glycol with an average molecular weight of 2,000, 30 parts of dibutyl phthalate, 2 parts of dibutyltin dilaurate, 10 parts of Bengara,
A formulation consisting of 2 parts of UV absorber and 118 parts of inorganic filler was prepared.

Both components A and B were stirred and mixed at a weight ratio of 1:2.

At this time, as the foamed elastic rubber particles, as shown in Table 1,
Foamed urethane rubber particles having a diameter of 3 fins were blended at a weight ratio of 10% to the urethane composition. Add 1 portion of Portland cement to the acrylic emulsion as a base treatment agent.
After applying the cement best blended in step 3, it was applied uniformly to a thickness of 11 mm on Ascon, which had been further coated with a urethane-based aqueous primer.

The urethane track was cured to the point where it could be walked on the next day. Subsequently, as topping 1, the liquid polyether urethane composition described above was applied to a thickness of 2 fl, and before it gelled, a urethane topping material (3 to 6 fi diameter) was uniformly and excessively sprinkled. The next day, the excess topping material was removed and a urethane track with a total thickness of 13 fi was completed.

As shown in the following table, this truck has excellent physical properties, durability, and motion suitability, and has high peel strength at 50°C, and no peeling accidents were observed even after one year.

[Example 2] As a two-component curing liquid polyether urethane composition,
The same urethane prepolymer as in Example 1 was used, and the curing agent component was 0 methylenebisorthochloroaniline.
．． The same formulation as in Example 1 was carried out except that the amount of polyoxypropylene glycol having an average molecular weight of 3 equivalents and an average molecular weight of 2,000 was changed to 0.6 equivalents. In addition, as a surface treatment agent, SBR latex, Boltland cement, and silica sand were used at a ratio of 1:3:1, respectively.
I used cement paste mixed with Subsequently, a 10% mixture of the urethane composition and foamed SBR rubber (2 to 3 diameter) was uniformly applied to a thickness of 10.5 m on the ascon coated with the epoxy water-based primer.

Continuing the same construction as in Example 1, a urethane track with a total thickness of 13 mm was completed.

This truck was also highly durable and comfortable to use. Furthermore, no peeling or blistering accidents occurred.

[Comparative Example 1] All procedures were the same as in Example 1 except that polyoxypropylene glycol having an average molecular weight of 2,000 was used alone as the curing component of the urethane composition without using aromatic diamine in combination. Construction was carried out.

This truck had extremely poor physical properties and durability, and could not be put to practical use. This indicates that the combination of aromatic diamine is essential.

FIG. 1 is a diagram showing the relationship between the equivalent percent of methylenebisorthochloroaniline in the methylenebisorthochloroaniline-polypropylene glycol 2,000 curing system and the elongation, tensile strength, and hardness of the cured product. elongation, -
〇- represents tensile strength, and -△- represents hardness. It can be seen from the figure that the physical properties are extremely poor when polyol is used alone.

[Comparative Example 2] A urethane track was constructed using the same method as in Example 2 except that the foamed SBR rubber particles were not mixed into the urethane composition.

This truck had a shock absorption value, feel of use, and insulation effect each reduced by 20% compared to the truck of Example 2.

As a result, athletes suffered from significant muscle fatigue during practice. Furthermore, the peel strength at 50°C decreased by 30%.

[Comparative Example 3] A urethane track was constructed using the same method as in Example 2, except that 20% of non-foamed SBR recycled rubber tire particles were mixed into the urethane composition.

The impact absorption value, usability, and heat insulation effect of this truck were each reduced by 10% compared to those of Example 2.

[Comparative Example 4] In Example 1, except that the base treatment was not performed,
All urethane tracks were constructed using the same method.

This truck had good physical properties, durability, shock absorption, and usability, but the peel strength at 50°C was Ikg/
It was extremely weak at less than 25m, and as a result, an accident occurred where the ascon was peeled off from the surface within 6 months after construction.

The results of each Example and Comparative Example are summarized in Table 1 below.

As shown in Table 1, the urethane track material made of the urethane composition specified in the present invention and foamed elastic rubber particles mixed therein is constructed on the ascon, which has been previously treated with a specific surface treatment. It is clear that all of the above problems have been solved, and the track is comfortable and records well without peeling or blistering.Also, when applying the liquid urethane composition to a sloped ascon surface, the fluidity is appropriate. As a result, it is clear that there is an advantage that it is possible to construct uniform thickness from 1 to 8 courses.

(Margin below)

[Brief explanation of the drawings] Figure 1 is a diagram showing the relationship between the equivalent percentage of methylenebisorthochloroaniline in the methylenebisorthochloroaniline-polypropylene glycol 2,000 curing system and the elongation, tensile strength, and hardness of the cured product. And = 9- is elongation, -
〇- represents tensile strength, and -8- represents hardness. Patent applicant Kanebo NSC Co., Ltd. Agent
Patent Attorney Yukihiko Nishifuji Figure 1

Claims (20)

[Claims] (1) A polymer cement paste layer containing a synthetic resin emulsion and portland cement as main components, a primer layer, and a polyurethane layer containing foamed elastic rubber particles are sequentially laminated on an asphalt concrete surface, and a portion of the polyurethane layer is A paving material layer for a urethane track characterized by being composed of urea bonds and three-dimensional crosslinks. (2) The paving material layer of the urethane track according to claim 1, wherein the asphalt concrete surface contains crushed stone, sand, and straight asphalt or cutback asphalt. (3) The paving material layer of a urethane track according to claim 1 or 2, wherein the synthetic resin emulsion is a styrene-butadiene rubber latex or an acrylic acid-based synthetic resin emulsion. (4) The paving material layer of a urethane track according to any one of claims 1 to 3, wherein the primer is an emulsion or latex of polyurethane, epoxy resin, or styrene-butadiene rubber. (5) The urethane track pavement according to any one of claims 1 to 4, wherein the foamed elastic rubber particles are foamed styrene-butadiene rubber or polyurethane rubber with an average particle size of 4 to 50 mesh. material layer. (6) Claim 1 in which the urea bond is formed from an aromatic diamine and an aromatic polyisocyanate.
A paving material layer for a urethane track according to any one of items 5 to 5. (7) The paving material layer of a urethane track according to claim 6, wherein the aromatic diamine is methylenebisorthochloroaniline or 2,2'-dichlorobenzidine. (8) The paving material layer of a urethane track according to any one of claims 1 to 7, wherein the three-dimensional crosslinking is formed from an aromatic polyisocyanate and a polyalkylene ether polyol. (9) The paving material layer of the urethane track according to any one of claims 1 to 8, wherein the polyurethane layer is formed from aromatic diamine, aromatic polyisocyanate, and polyalkylene ether polyol. . (10) The paving material layer of a urethane track according to claim 9, wherein the polyalkylene ether polyol has an average molecular weight of 400 to 4,000. (11) A polymer cement paste layer, a primer layer, and a polyurethane layer are sequentially laminated on an asphalt concrete surface, and a two-component curing liquid polyether urethane composition containing foamed elastic rubber particles is used as the polyurethane layer. A construction method for urethane tracks that is characterized by: (12) The method for constructing a urethane track according to claim 11, wherein the polymer cement paste layer is made of a synthetic resin emulsion and Portland cement. (13) The method for constructing a urethane track according to claim 12, wherein the synthetic resin emulsion is a styrene-butadiene rubber latex or an acrylic acid-based synthetic resin emulsion. (14) Claim 11 or 1, wherein the foamed elastic rubber particles are foamed styrene-butadiene rubber or polyurethane rubber with an average particle size of 4 to 50 mesh.
The construction method for the urethane track described in Section 2. (15) Two-component curing liquid polyether urethane composition has at least two hydroxyl groups and has an average molecular weight of 400 or more
It consists of a polyether urethane prepolymer having free isocyanate groups obtained by addition-reacting 4000 polyalkylene ether polyol and aromatic polyisocyanate, and a curing agent whose main components are aromatic diamine and the polyalkylene ether polyol. A method for constructing a urethane track according to any one of claims 11 to 14. (16) The method for constructing a urethane track according to claim 15, wherein the aromatic polyisocyanate is tolylene diisocyanate or methylene bisphenyl isocyanate. (17) The paving material layer of a urethane track according to claim 15, wherein the aromatic diamine is methylenebisorthochloroaniline or dichlorobenzidine. (18) Polyether urethane prepolymer is 30 to 8
Claim 15 which is a mixture of a polyether urethane prepolymer having 0% by weight of three or more free isocyanate groups and a polyetherurethane prepolymer having 20 to 70% by weight of two free isocyanate groups. Urethane track construction method described in section. (19) The polyether urethane prepolymer having 3 or more free isocyanate groups contains 1.2 to 1.2 to 1.2 to 1.2 to 1% of the hydroxyl group equivalent of the polyalkylene ether polyol and polyalkylene ether diol having 3 or more hydroxyl groups. The method for constructing a urethane track according to claim 18, wherein 2.5 equivalents are added. (20) Aromatic aroma in which the two-component curing liquid polyether urethane composition has active hydrogen atoms in an amount of 0.7 to 1.2 equivalents per equivalent of free isocyanate groups in the polyether urethane prepolymer having free isocyanate groups. The method for constructing a urethane track according to any one of claims 11 to 19, which is a mixture of a group diamine and a polyalkylene ether polyol.