JPH0745606B2 - Polyvinyl chloride resin tile - Google Patents

Description

TECHNICAL FIELD The present invention relates to a polyvinyl chloride resin tile, and more specifically, to a product obtained by reacting heavy calcium carbonate with a resin acid and a petroleum resin. The present invention relates to a vinyl chloride resin tile that has improved workability, quality, environmental hygiene, etc. of tiles compared to conventional products by blending surface-treated heavy calcium carbonate into a polyvinyl chloride resin tile. .

"Prior art and problems" The main component of polyvinyl chloride resin tile is polyvinyl chloride resin, which is combined with a plasticizer and a binder, contains heavy calcium carbonate as an extender, and is white. Precipitated calcium carbonate may be used as a gloss smoothing agent and a surface strength improver.

In order to provide sufficient strength, vinyl chloride as a main component needs to be at least 25% by weight, and generally 30% by weight or more is used. Such tiles are called homogeneous vinyl tiles, and JIS standards are defined, but since vinyl chloride is expensive, it is treated as a high-grade product.

Thus, conventionally, a large amount of tiles called vinyl asbestos tiles having a vinyl chloride content of 22% by weight or less, generally 10 to 15% by weight, which are called semi-hard or soft vinyl asbestos tiles, have been produced. Although this is a low-grade product, it had the excellent advantage of being inexpensive, but there are many extender pigments due to the decrease in vinyl chloride resin. Was supplemented with asbestos.

However, since asbestos is a fine fibrous inorganic substance, industrial hygiene and environmental problems such as the occurrence of silicosis caused by dust have become a major social issue, and the tile industry has voluntarily restricted asbestos from using it. . Therefore, there is a strong demand for the development of a reinforcing filler that replaces asbestos. Currently, tiles in this field (hereinafter referred to as "non-astyle") are used as an alternative to asbestos.
Surface-treated precipitated calcium carbonate as disclosed in 59-220555, fibrous organic matter, acicular minerals, etc. are used, but they are not sufficient in terms of quality, price, etc. compared to asbestos, The advent of even better fillers is desired.

The physical properties and composition desired for non-astyle will be explained below.Physical properties that pose a problem with PVC tile include length change due to water absorption, thermal expansion, dents, loss on heating, chemical resistance, etc. In many cases, destruction is caused by mistakenly dropping it during construction at (0 to 8 ° C) or applying uneven force such as holding the edge of a square tile. There is a strong demand.
Further, in addition to the problem of strength, the problem of the manufacturing process is large. That is, since a manufacturing method is adopted in which necessary components are kneaded, rolled, taken out into a continuous sheet, and cut into rated dimensions to form tiles, adhesiveness to the roll is required.
As mentioned above, Non-Astyle has a small amount of vinyl chloride resin and uses a large amount of an extender pigment, which is called heavy calcium carbonate, as the extender, and thus is less sticky. If the temperature of the roll during kneading and sheeting is increased, the tackiness is improved as much as possible, but if the roll temperature is increased, the smoothness of the tile surface deteriorates. Therefore, it is necessary that the workability of the tile composition is as good as possible at a temperature as low as possible and the adhesion to the roll is good. Therefore, from the viewpoint of vinyl chloride resin, a copolymer with vinyl acetate is used without using a straight vinyl chloride polymer in order to improve the adhesiveness and workability, but the cost and various physical properties are better if vinyl acetate is not used. Desirable for.

Next, the calcium carbonate used as a filler for non-style is described. Heavy calcium carbonate used as a filler is produced at low cost by physically crushing natural limestone and classifying it.

On the other hand, precipitated calcium carbonate is made by reacting CaO obtained by firing natural limestone at high temperature with water to convert it into Ca (OH) ₂ and then reacting it with CO ₂ to chemically precipitate CaCO _3. It has a narrow particle size distribution width, and the average particle size can be adjusted. Therefore, it has a crystal form with a uniform particle size and is well activated. This precipitated calcium carbonate, which has been subjected to a surface treatment, is used as a homogeneous type,
Since the strength of this type of tile is sufficiently guaranteed by the vinyl chloride polymer as the main component, it is used only for improving white gloss, surface smoothness and workability, as described above.

As mentioned above, PVC resin tiles
It is roughly divided into two types, one is a homogeneous type, the other one is a non-style two major series, JIS standardized, the main component is the straight polymer of PVC,
The latter is a vinyl chloride-vinyl acetate copolymer, heavy calcium carbonate is commonly used as a bulking agent, precipitated calcium carbonate is used as a smooth white brightening agent in the former, and a binder is non-style.

The present inventors have conducted research to improve the adhesion to the non-astyle roll, the adhesiveness, and the strength, and the results thereof have already been applied for a patent (JP-A-60-85915,
60-155780, 61-34290). Further, as described above, there is JP-A-59-22055, but all of them are not sufficiently satisfactory in terms of quality and cost.

"Means for Solving Problems" There is also a method of using surface-treated precipitated calcium carbonate as a substitute for conventional asbestos for non-astyle as described in JP-A-59-220555. Manufacturing cost is higher than high quality calcium carbonate. Therefore, it is preferable that the surface-treated heavy calcium carbonate has physical properties more than that of the precipitated calcium carbonate.

The present inventors have paid attention to this point, and as a result of earnest research, surface-treated heavy calcium carbonate for polyvinyl chloride-based resin tiles exhibiting physical properties superior to those of conventional surface-treated precipitated calcium carbonate and surface-treated heavy calcium carbonate. Was successfully developed.

That is, the present invention is a product obtained by reacting a resin acid with a petroleum resin in a polyvinyl chloride resin tile having a vinyl chloride resin content of 22% by weight magnetization and containing no asbestos as a filler. The present invention is directed to a polyvinyl chloride resin tile containing 2 to 20% by weight of treated heavy calcium carbonate.

Conventionally, surface treatment agents used for this kind of calcium carbonate are mainly natural resin acids such as diterpenic acid and abietic acid, petroleum resins, fatty acids, and salts thereof.
It is a reaction product of an ester or an unsaturated carboxylic acid such as maleic acid. And these are used individually or in combination of 2 or more types. On the other hand, when the surface treatment is performed on the heavy calcium carbonate, the dry treatment is the cheapest. In the case of dry treatment, a method is employed in which a surface treatment agent in a solid state is heated in a mixed state with heavy calcium carbonate, and the surface treatment agent is melted and adsorbed on the surface of the heavy calcium carbonate powder. Therefore, the melting point of the surface treatment agent is very important. On the other hand, from the viewpoint of use, how much the tile compound composition adheres to each roll during the manufacturing process is very important in terms of work, and this is because of the surface treatment agent for the heavy calcium carbonate to be compounded. It has a great relationship with the melting point. Taking these things into consideration, it is necessary to consider how to set the melting point of the surface treatment agent from both dry processing conditions and tile manufacturing conditions (roll temperature). However, even if these surface-treating agents are used alone or in combination of two or more kinds, it is not possible to obtain a melting point that achieves both of these purposes. That is, when used alone, the range of the semi-molten state is narrow, and even if two or more surface treatment agents having different melting points are simply used in combination, a uniform semi-molten state cannot be obtained. Cannot be satisfied at the same time.

The present inventors have found that the reaction product of a resin acid and a petroleum resin, which is produced by reacting a resin acid and a petroleum resin by heating, is in a semi-molten state in a wide temperature range and achieves the intended purpose. It was

In the present invention, the resin acid and the petroleum resin have a weight ratio of 1/100.
-100 to 100/1 is preferable, and more preferably 1/10 to 10/1. Further, when the heavy calcium carbonate surface-treated with this reaction product is blended with vinyl chloride, a physical strength comparable to asbestos can be obtained. This is considered to be due to the good compatibility between the treating agent and the vinyl chloride resin. The average particle size of the heavy calcium carbonate used in the present invention is preferably in the range of 0.5 to 50 μ. As a method for measuring the average particle size, calculation is performed using a conversion formula from the measured values of the air permeation method and the centrifugal light transmission method. In case of air permeation type specific surface area measurement method, average particle size =
Convert the average particle size from the formula 6 / (specific surface area x specific gravity),
In addition, from the centrifugal type light transmitting particle distribution, the particle size of 50% by weight in the particle size distribution is taken as the average particle size. If the average particle size is smaller than 0.5 μm, each particle will aggregate,
Even if it is mixed with PVC tile, the desired physical properties cannot be obtained. Also 50μ
If it is larger than m, the surface area of the particles becomes small, and it is impossible to adsorb the minimum amount of surface treatment required to maintain the physical properties required for PVC tile. Therefore, the desired physical properties cannot be obtained.

Regarding the temperature and mixing time during dry treatment, the softening point of the reaction product decreases when the resin acid and the petroleum resin are reacted at a high ratio of the resin acid, but the temperature of the system to be mixed is 80%. If it is below ℃, even if the treatment agent is adsorbed on the surface of the heavy calcium carbonate, if it is added to the PVC tile,
The desired physical properties cannot be obtained. In particular, the adhesiveness to each roll in the manufacturing process of the tile composition is poor. Therefore, it is necessary to keep the temperature of the mixing system at 80 ° C. or higher during the dry treatment. Further, the mixing time is preferably 3 minutes or more, and if the mixing time is less than 3 minutes, it is difficult to obtain surface-treated heavy calcium carbonate which imparts predetermined physical properties to the PVC tile.

In the present invention, the main component of vinyl chloride resin is 22% by weight.
Hereinafter, the surface-treated heavy calcium carbonate is blended in an amount of 2 to 20% by weight. If the surface-treated heavy calcium carbonate is less than 2% by weight, sufficient strength is not imparted, while if it exceeds 20% by weight, the cost is increased and the strength of the product tile tends to be lowered.

The tile composition thus obtained, to which the surface-treated ground calcium carbonate was added, was put into, for example, a Banbury mixer,
Kneading at a high temperature of ~ 180 ° C, pouring the kneaded product into a mixing roll made of two rotating bodies with appropriate gaps that rotate in opposite directions to each other, and with the thickness of the ring on the surface of the rotating body also serving as one layer of kneading. It is formed into a band, and the ring is cut at one place, taken out in a linear band, applied to a calender roll, thinned to form a sheet, cooled and cut into a predetermined size to obtain a tile product of a fixed shape.

The viscosity of the kneaded material is increased by the surface-treated heavy calcium carbonate during the tile manufacturing process, and therefore the kneaded material adheres well to the mixing roll and is more susceptible to kneading. Surface treatment The surface treatment agent is adsorbed on the surface of the calcium carbonate particles as a surface layer, and the dispersibility is high. Therefore, it is well dispersed in the polymer and in the polymer is in a state of being strongly dispersed and bonded to the polymer. , Gives great elasticity to the whole polymer, and therefore exhibits excellent reinforcing properties.

Also, since the dispersibility is high, it does not hinder the viscosity of the polymer,
Therefore, there is an effect that the adhesive can be replaced or the amount of the adhesive can be reduced. There is also an advantage that the temperature of the process can be lowered. Further, the conventional asbestos type has oil absorbency in asbestos, and the plasticity of DOP, DHP and the like is adsorbed by asbestos and inhibits the plasticizing effect, but since the present invention does not use asbestos, The amount can be reduced.

Since the surface-treated heavy calcium carbonate is well dispersed, in addition to the above-mentioned adhesive effect and reinforcing effect, it is also excellent in white gloss and smoothness as conventionally known.

JP-A-60-85915 and JP-A-60-155 proposed by the present applicant
As described in 780, surface-treated precipitated calcium carbonate is also effective as an alternative to asbestos in asbestos tiles. However, surface-treated ground calcium carbonate has a lower oil absorption than surface-treated precipitated calcium carbonate,
It has the advantages of good distribution and generally low manufacturing costs. If the amount of oil absorption is low, the amount of plasticizer will be excessive for the same amount of plasticizer, and this amount will soften the tile and consequently improve the strength of the tile. Also, heavy calcium carbonate is
Since the surface is more inactive than the precipitated calcium carbonate, there is almost no secondary agglomeration between particles, so it shows better dispersibility than the precipitated calcium carbonate, and this good dispersibility results in tile strength. Improve. Considering the manufacturing cost, precipitated calcium carbonate ignites limestone to decompose it into CaO and CO ₁ and digests CaO with H ₂ O to produce Ca (OH).
_2, and making CaCO ₃ by the CO ₂ is reacted to the Ca (OH) _2. On the other hand, since heavy calcium carbonate is finely divided by mechanical pulverization, there is a large cost difference. Even if it is wet crushed and dried, it is cheaper than precipitated calcium carbonate. Therefore, when surface-treated heavy calcium carbonate is used as an alternative to asbestos for the asbestos tile, the same or more effects than the precipitated calcium carbonate are obtained, which is a great cost advantage. Further, the surface treatment of heavy calcium carbonate having a large specific surface area, that is, a small particle size gives better results in tackiness, strength and the like than the surface treatment of heavy calcium carbonate having a small specific surface area.

"Examples" Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

Example 1 Using a Hensiel mixer, 10 kg of ground calcium carbonate having a specific surface area of 25000 cm ² / g adjusted using a micron grinder and a vibration mill, and 300 g of a reaction product obtained by reacting a resin acid and a petroleum resin in a ratio of 3: 7 are mixed. Used for mixed treatment. This sample was tested with the following formulation. The results are shown in Table 1.

The method for producing the sample tile and the test method are as follows.

Composition: 100 parts by weight of polyvinyl chloride resin (Kaneka MB-1008) Surface-treated heavy calcium carbonate 60 Heavy calcium carbonate 600 DHP 35 Binder 4 (Stabilizers, colorants, etc. are omitted.) Sample tile Preparation method: The above-mentioned compound was kneaded with a small test roll for 5 minutes at 100 to 150 ° C., adjusted to a thickness of 2 mm, and taken out as a tile piece of 30 × 30 cm ² .

Test method: Strength test: In a thermostatic chamber adjusted to 3 ° C, drop 50 g of iron balls from a height of 1.5 m on the test tile pieces placed horizontally on the floor to determine the cracking state.

Roll tackiness: Adhesion of the compound to the roll (winding property) is judged when kneading with a mixing roll.

Cohesiveness: Judged by the time required for the compound to be uniformly mixed when kneaded.

Thermal stability: The tile sheet is heated in a gear oven at 180 ° C for 50 minutes and judged by the presence or absence of discoloration.

Comparative Example 1 A test was conducted in the same manner as in Example 1 except that the reaction product of the resin acid and the petroleum resin was replaced with the resin acid. The results are shown in Table 1.

Comparative Example 2 A test was conducted in the same manner as in Example 1 except that the reaction product of the resin acid and the petroleum resin was replaced with petroleum resin. The results are shown in Table 1.

[Operation / Effect] As described above, the present invention contains the heavy calcium carbonate surface-treated with the reaction product of the resin acid and the petroleum resin, and thus the dry treatment of the heavy calcium carbonate and the tile production are performed. Satisfies the required physical properties, dry processing temperature,
Since the semi-molten state can be adjusted by changing the reaction ratio between the resin acid and the petroleum resin even if the temperature of the roll during the tile production is changed, it is possible to respond promptly. The reaction between the resin acid and the petroleum resin in the present invention is considered to be that hydrogen at the terminal of the petroleum resin reacts with the carboxyl group of the resin acid and is bonded.

Since the surface-treated heavy calcium carbonate acts as a reinforcing agent, the resin tile of the present invention can provide a new type tile having strength equal to or higher than that of the asbestos-containing tile. Moreover, the surface-treated heavy calcium carbonate has excellent caking properties in the manufacturing process, can be manufactured at low temperature, and can replace expensive caking agents or reduce the amount of caking agents used. Therefore, not only the cost can be reduced compared to the asbestos type, but also the environmental health problems caused by asbestos can be solved. Further, the cost can be greatly reduced as compared with the precipitated calcium carbonate.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location E04F 15/10 104 7416-2E (56) References JP-A-59-220555 (JP, A) JP-A-54 -112955 (JP, A) JP-A-61-34290 (JP, A) JP-A-47-34743 (JP, A) JP-B-43-18463 (JP, B1)

Claims (5)

[Claims] 1. A polyvinyl chloride resin tile having a vinyl chloride resin content of 22% by weight or less and containing no asbestos as a filler, the surface of which is obtained by reacting a resin acid with a petroleum resin. A polyvinyl chloride resin tile containing 2 to 20% by weight of treated heavy calcium carbonate. 2. The average particle size of ground calcium carbonate is 0.5 to 50.
The resin tile according to claim 1, which has a thickness of μm. 3. A product of a resin acid and a petroleum resin is obtained by reacting a resin acid / petroleum resin in a weight ratio of 100/1 to 1/100, and the softening point of the product. Is in the range of 50 to 200 ° C. The resin tile according to claim 1. 4. The resin tile according to claim 1, wherein the product of resin acid and petroleum resin is used in an amount of 0.1 to 10% by weight based on ground calcium carbonate. 5. A patent for which surface treatment is carried out by using a mixing and dispersing machine such as a Henschel mixer and keeping the temperature in the mixer at 80 ° C. or higher to mix the heavy calcium carbonate with the product for 3 minutes or longer. The resin tile according to claim 1.