JP2958642B1 - Method for producing vinyl chloride regenerated resin - Google Patents

Abstract

An object of the present invention is to provide a method for producing a vinyl chloride-based regenerated resin from a raw material of a vinyl chloride product having a different melting temperature range without increasing a heating temperature or elongating a heating time. A first group of resin material pieces mainly composed of hard vinyl chloride resin is charged into a first cylinder (17) of a main injection part (12) of an extruder (11), and a second cylinder (3) of a sub injection part (13) is provided.
A second group of resin material pieces mainly composed of a soft vinyl chloride resin is charged into the inside of the resin material 2. The material pieces charged in the respective cylinders 17 and 32 are kneaded and melted separately, merged and kneaded, and extruded from the die 16 as a vinyl chloride-based regenerated resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method for producing a vinyl chloride-based regenerated resin by melting and kneading a vinyl chloride-based resin product.

[0002]

2. Description of the Related Art Vinyl chloride resins can be used to produce products of various hardnesses from soft to hard by applying a plasticizer, and are widely used in various products because of their low cost and suitable for mass production. Such a vinyl chloride resin is generally mixed with a powdery vinyl chloride resin raw material (this is referred to as a raw material resin), as a secondary material, with a plasticizer, a stabilizer, a bulking agent, a pigment, etc., and then kneaded to form a pellet or powder. Shaped resin (hereinafter referred to as vinyl chloride resin)
Again into the molding machine, and calendar processing according to the application,
A molded product is obtained by extrusion, injection molding, or the like. Products molded in this way are roughly classified into hard and soft vinyl chloride resin products depending on the degree of polymerization of the raw resin and the mixing ratio of the plasticizer. by the way,
In recent years, reuse of synthetic resins has been required from the viewpoint of preventing environmental pollution, and vinyl chloride resin products are no exception.
Therefore, a used vinyl chloride resin product is melted again by an extruder or the like to obtain a vinyl chloride regenerated resin, which is used to produce a so-called reprocessed product made of vinyl chloride again.

[0003]

However, as described above, a wide range of products from soft to hard can be produced by applying a plasticizer to the vinyl chloride resin, so that the vinyl chloride resin is used as a raw material of a recycled vinyl chloride product. If a product (hereinafter referred to as a raw vinyl chloride product) is used without any separation, the following problems occur.

[0004] If the soft and hard raw vinyl chloride product is thin, it is cut as it is, and if it is thick, it is pulverized or cut into small pieces and melted in, for example, an extruder. Then, since the soft raw material vinyl chloride product contains a large amount of a plasticizer, the flowability in the device tends to be good and to be dissolved quickly. On the other hand, hard raw vinyl chloride products tend to be difficult to dissolve due to the small amount of plasticizer. Therefore, if the soft raw vinyl chloride product is melted first in a state where both raw vinyl chloride products are mixed, the hard raw vinyl chloride product will be in a state as if floating in the dissolved soft raw vinyl chloride product. As a result, the hard raw vinyl chloride product was not easily dissolved, and depending on the conditions, the dissolving ability was sometimes inferior to that of the hard raw vinyl chloride product alone.

In this case, by increasing the kneading time, that is, by lengthening the heating time, the hard raw vinyl chloride product can be finally dissolved, but the prolonged heating deteriorates the resin. And the resin is decomposed to cause dechlorination, which is not desirable. It is also conceivable to increase the heating temperature, but similarly, it causes deterioration and decomposition of the resin. Furthermore, if the hard raw vinyl chloride product is mixed with the soft raw vinyl chloride product in the form of powder or very small pellets as in the above-mentioned raw resin, it can be easily dissolved. It must be in the form of powder or pellets, which is very troublesome and not cost-effective.

The present invention has been made by paying attention to such problems existing in the prior art. It is an object of the present invention to provide a production method for producing a vinyl chloride-based regenerated resin from raw vinyl chloride products having different melting temperatures without increasing the heating temperature or the heating time.

[0007]

In order to achieve the above object, according to the first aspect of the present invention, a resin material mainly composed of a vinyl chloride resin divided into a plurality of groups which melts in different temperature zones. While heating the pieces in separate heating chambers for each group, they are kneaded and melted by a kneading device, and the molten materials of each group are combined and kneaded under heating by a kneading device to obtain substantially uniform chloride. The gist of the present invention is to manufacture a vinyl-based recycled resin. According to the second aspect of the present invention, a first group of resin material pieces mainly composed of a hard vinyl chloride resin is introduced into a first heating chamber, kneaded and melted by a kneading device under heating, and soft A second group of resin material pieces mainly composed of a vinyl resin is introduced into a second heating chamber, kneaded and melted by a kneading device under heating, and the two melted materials are combined to form a kneading device. The gist of the present invention is to produce a substantially homogeneous vinyl chloride regenerated resin by kneading under heating.

Here, the raw vinyl chloride product includes both a product newly manufactured based on a raw resin and a product which has already been recycled. As a raw material PVC product,
Firstly, molded products obtained by calendering, extruding, injection molding, etc., a vinyl chloride resin obtained by mixing a plasticizer, a stabilizer, a bulking agent, a pigment, etc. as a secondary material in a raw material resin are listed. Can be As raw material resin for vinyl chloride resin, not only vinyl chloride polymer but also other comonomers (styrene, methyl acrylate, acrylonitrile, vinylidene chloride, maleic anhydride, isobutylene, 2-chloroacetate, vinyl acetate, etc.) Polymers are also included. The degree of polymerization of the raw resin varies, and the degree of polymerization is low (about 700 to 900), medium degree (1000 to 1).
Each polymer having a high degree of polymerization (about 500) and a high degree of polymerization (about 2000 to 3000) is widely distributed depending on the use of the product. Further, as a plastic modifier having good compatibility with vinyl chloride, A
BS (acrylonitrile-butadiene-styrene terpolymer), MBS (methylmethclair-butadiene-styrene terpolymer), chlorinated polyethylene, and the like may be added.

Examples of the plasticizer as an auxiliary material include adipate esters such as dioctyl adipate (DOA), and phthalate esters such as didecyl phthalate (DDP), dioctyl phthalate (DOP) and dibutyl phthalate (DBP). , Tricresyl phosphate (T
Examples thereof include phosphate esters such as CP), epoxidized vegetable oils, and nitrile-based synthetic rubbers. As a stabilizer as an auxiliary material, for example, a lead salt (lead white, dibasic phosphorous acid, etc.), metal soap (soap with a metal such as lead, cadmium, zinc, etc. and stearic acid, uraric acid, etc.), organic Examples include tin stabilizers, epoxy stabilizers, and organic phosphite compounds. Examples of the extender as an auxiliary material include calcium carbonate, clay, and silica. In addition, a lubricant and a pigment, and in some cases, a flame retardant, a foaming agent, and a fungicide are mixed as auxiliary materials.

The starting vinyl chloride product contains such materials, but the thermoplasticity thereof is affected by the degree of polymerization of vinyl chloride and the blending ratio of the plasticizer. Particularly, the mixing ratio of the plasticizer greatly affects the plasticity. Vinyl chloride has thermoplasticity, and the intermolecular force is reduced by heating, and fluidity appears. Therefore, as the degree of polymerization increases, the intermolecular force tends to increase and the fluidity tends to deteriorate. On the other hand, the plasticizer has a function of weakening the intermolecular force, and the addition of the plasticizer increases the fluidity. Also,
As the blending ratio of the plasticizer increases, the flow temperature decreases. On the other hand, if the addition ratio of the plasticizer increases, the product itself becomes soft and flexible. If the plasticizer is heated to a temperature higher than the flowing temperature of the vinyl chloride resin without adding a plasticizer, there is a risk of thermal decomposition. Therefore, it is necessary to add a plasticizer also in this regard.

Due to the nature of such a plasticizer, several methods are conceivable for separating the raw vinyl chloride product into a plurality of groups which are melted in different temperature zones. As a first sorting method, a melting temperature is measured in advance for each raw vinyl chloride product, and the product is separated into a plurality of groups according to the melting temperature. As a second sorting method, a first group of resin material pieces mainly composed of a hard vinyl chloride resin and a second group resin mainly composed of a soft vinyl chloride resin for soft products and hard products which are generally roughly classified. This is a method of measuring the melting temperature of each group by separating the material into material pieces. The first fractionation method is effective when a plurality of types of raw material vinyl chloride products are obtained in large quantities, and the temperature range in which melting is performed can be determined quite limited. The second fractionation method distinguishes between a soft product and a hard product, which are generally classified by the amount of a plasticizer in a vinyl chloride resin product, and it is not necessary to measure the melting temperature range of each product. The temperature zone where the melting is performed is wider than in the first sorting method.

[0012] As described above, when the first and second resin material pieces are separately separated and melted, if the polyvinyl chloride resin products having a plurality of compositions whose melting temperatures are very close to each other, they are deliberately separated. It is not necessary. It is possible to melt together with a certain temperature zone that has a certain temperature range. Conversely, if a vinyl chloride resin product whose melting temperature is significantly higher than other resins is mixed in the same group, it must be heated for a long time or at a high temperature to melt the resin product. Resin degradation and decomposition occur. Therefore, when vinyl chloride resin products having a plurality of compositions are included in the same group, it is necessary to put together products having similar dissolution temperatures. Conversely, if the above-mentioned problems occur if the melting temperatures are different and they are melted together, the vinyl chloride resin products need to be separately melted as a separate group. As described above, since the dissolution temperature has a negative correlation with the mixing ratio of the plasticizer, those having similar mixing ratios of the plasticizer may be grouped into one group. At this time, those having a high plasticizer compounding ratio (soft vinyl chloride resin) are easily combined into one group even if the plasticizer compounding ratio is considerably different, and those having a low plasticizer compounding ratio (hard vinyl chloride resin) Unless the blending ratio of the plasticizer is close, it tends to be difficult to form a group. The relationship between the plasticizer and the hardness is important. The less the plasticizer, the higher the hardness of the vinyl chloride resin product becomes, and the more the plasticizer is included, the more gradually the product becomes flexible. However, flexibility is not only a matter of pure hardness, but also depends on the shape of the product, the degree of polymerization of vinyl chloride, and the like.

In general, a plasticizer containing 0 to less than 10% by weight of a plasticizer is defined as a hard vinyl chloride resin.
Those having less than 30% by weight are semi-rigid vinyl chloride resins, and those having 30% by weight or more are soft vinyl chloride resins. However, whether the material is soft or hard is not always based on this general definition because a relative element is large and a shape element is added. For example, even if the amount of the plasticizer to be the above-mentioned soft vinyl chloride resin is included, the plasticizer contains 30% by weight or more of the plasticizer when viewed from the very large amount of the plasticizer, and the bulky shape If it is a product, it may be called a hard or semi-hard vinyl chloride resin. The drawing between hard and semi-hard and between semi-hard and soft is delicate, and the numerical value of the amount of the plasticizer added is not absolute. Further, depending on the degree of polymerization of the raw resin, the amount of the plasticizer may be at least classified as a soft vinyl chloride resin, or conversely, the amount of the plasticizer may be classified as a hard or semi-hard vinyl chloride resin at most. is there. What is important in the present invention is that, in the raw material vinyl chloride product, a group of a predetermined range of plasticizer addition amount that melts in a predetermined temperature range and a group of a predetermined range of plasticizer addition amount that melts in a predetermined temperature range different from that. It is divided into.

Generally, products included in the soft vinyl chloride resin include, for example, films and sheets. Examples of films, sheets and the like include food packaging films, greenhouse sheets, agricultural sheets, vehicle sheet materials, hose tubes, foam sheets for building materials, flooring, bags, footwear, gloves, and the like. In addition, as the hard thermoplastic resin material, various industrial products such as water pipes, industrial board materials, building materials such as arcades, measuring cases for food, containers for foods such as seasoned laver, containers for non-foods such as shampoo, lightweight trays, and the like. And the like. Depending on the amount of the plasticizer added, these may be classified as soft vinyl chloride resins or semi-rigid vinyl chloride resins. It is not absolute because it is sometimes classified as a vinyl resin.

[0015]

According to the first aspect of the present invention, the resin material pieces are separately dissolved and then mixed for each group, so that any one of the resin material pieces having a high melting temperature does not remain without melting and is homogeneous. In addition to obtaining a regenerated resin, deterioration of the vinyl chloride-based regenerated resin can be suppressed as much as possible. According to the second aspect of the present invention, the hard vinyl chloride resin and the soft vinyl chloride resin are separately dissolved and then mixed, so that the hard vinyl chloride resin does not remain undissolved and is homogeneously recycled resin. And the deterioration of the vinyl chloride regenerated resin can be suppressed as much as possible.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. The extruder 11 for producing the mixed thermoplastic resin of the present invention includes a main injection section 12 and a sub-injection section 13. In the main injection section 12, a first cylinder body 17 as a first heating chamber is a hollow tubular body having a circular cross section.
A die 16 for extrusion molding is attached to the tip of the. At the base of the first cylinder body 17, a hopper 22 for guiding the raw material into the first cylinder body 17 is mounted. A plurality of band heaters 18a to 18j for heating the first cylinder body 17 are provided on the outer periphery of the first cylinder body 17.
Is installed. A temperature sensor 19 composed of a thermocouple is disposed adjacent to each of the band heaters 18a to 18j. A screw 20 as a kneading device is provided in the first cylinder body 17. A screw groove 21 is spirally formed on the outer periphery of the screw 20. The distal end of the screw 20 is a conical screw head 23, and the proximal end of the screw 20 is connected to a hydraulic motor 25 via a screw drive shaft (not shown).

The sub-injection unit 13 is disposed at an angle of about 30 degrees with respect to the main injection unit 12. The second cylinder body 32 as a second heating chamber is a hollow tubular body having a circular cross section, and the tip of the second cylinder body 32 is communicated with the vicinity of the center of the side of the first cylinder body 17. ing. Although the angle between the two cylinder bodies 17 and 32 in the present embodiment is about 30 degrees, this angle can be changed.

At the base of the cylinder body 32, a hopper 33 for guiding the raw material into the cylinder body 32 is mounted.
A plurality of band heaters 35a to 35d for heating the cylinder body 32 are mounted on the outer periphery of the cylinder body 32. A temperature sensor 36 composed of a thermocouple is disposed adjacent to each of the band heaters 35a to 35d. A screw 37 as a kneading device is provided in the cylinder main body 32. A screw groove 38 is spirally formed on the outer periphery of the screw 37. The proximal end of the screw 37 is connected to a hydraulic motor 39 via a screw drive shaft (not shown).

A first kneading portion 41 for kneading the first group of resin material pieces is provided behind the connecting portion between the first cylinder body 17 and the second cylinder body 32 in the first cylinder body 17. ing. The second cylinder main body 32 is a second kneading section 42 for kneading the second group of resin material pieces. The first kneading unit 41 in the first cylinder body 17
A third kneading section 43 for kneading the molten resin kneaded and joined at the first and second kneading sections 41 and 42 is provided in front of the first kneading section. The molten resin kneaded in the third kneading section 43 is pushed out of the die 16 by the pushing force of the screw 20. In the present embodiment, a plurality of extrusion passages 16 a having a circular cross section are formed in the die 16.

The operation of producing a mixed resin using such an extruder 11 and molding a recycled tube product will be described. First, the first and second cylinder bodies 17,
32 band heaters 18a to 18j, 35a to 35d
Is heated at a predetermined temperature. At the same time, hydraulic motors 25, 3
9 is driven to rotate each screw 20, 37. Then, two groups of resin material pieces A and B mainly composed of a vinyl chloride resin that melts in different temperature zones are prepared, and are charged from the hoppers 22 and 33. First group of resin material pieces A
Are kneaded in the first kneading section 41, and the second group of resin material pieces B are kneaded in the second kneading section 42. The resin material pieces A and B are melted in the first and second kneading units 41 and 42 heated by the band heaters 18a to 18j and 35a to 35d, and are kneaded by the screws 20 and 37 so as to be substantially uniform. Carried forward. The molten resin kneaded in a single group is further joined in the third kneading section 43 of the first cylinder body 17 and kneaded by the screw 20. Then, it is pushed out of the die 16 into a tube shape. The extruded tubular resin is cooled, cut into pellets, and obtained as a reworked product.

[0021]

EXAMPLES Two types of resin material pieces A selected from samples 1 to 5 were used as a first group of resin material pieces A and a second group of resin material pieces B, respectively. The inner diameters of the first cylinder body 17 and the second cylinder body 32 in this embodiment are each 100 mm.
The length P of the first kneading section 41 was designed to be 800 mm, the length Q of the second kneading section 42 was set to 800 mm, and the length P of the third kneading section 43 was designed to be 900 mm. In addition, each screw 2
For 0 and 37, those having a diameter of 90 mm were used, and the screw speed was 5 to 20 rpm. The maximum extrusion capacity of the extruder in this example was 150 kg / hr. Under such conditions, the band heaters 18a to 18j, 35a to
The work was performed while the first and second cylinder bodies 17 and 32 were sufficiently heated in advance by 35d, while adjusting the screw speed and the amount of injection into the first cylinder body 17 and the second cylinder body 32.

In the present embodiment, the band heaters 18a to 18a
The temperature setting of 18j, 35a to 35d was set lower as the content of the plasticizer was higher (the lower the hardness), and was set higher as the content of the plasticizer was lower (the higher the hardness). Further, the temperature was set so that the temperature gradually increased from the charging position (the positions of the hoppers 22 and 33) toward the junction. After the merging, the temperature was gradually lowered toward the die 16. In the third kneading section 43, the temperature was set in accordance with the mixing ratio of the molten resin sent from the first and second kneading sections 41 and 42. For example, the band heaters 18a to 18d in the first kneading unit 41 heat at 190 ° C. immediately before the merging point (the position of the band heater 18d),
In the band heaters 35a to 35d in the kneading section 42 of FIG.
It is assumed that heating is performed at 0 degree C. At this time, if the first group of resin material pieces A and the second group of resin material pieces B are sent out at an equal blending ratio, the heating temperature at the junction (the position of the band heater 18e) will be the same. The temperature was set to an intermediate temperature, that is, 170 ° C., and thereafter the temperature was gradually lowered toward the die 16.

In this embodiment, when the mixing ratio of the molten resin fed from the first and second kneading units 41 and 42 is not uniform, the temperature at the junction is set according to the mixing ratio. For example, in the above example, if 25% by weight from the first kneading section 41 and 75% by weight from the second kneading section 42 join, 190 × 0.25 + 150 × 0.75 = 160 (degrees C ).

[0024]

[Table 1]

Table 1 shows samples 1 to 5 and comparative samples 1 to 4.
Is shown. For each of the first to third material pieces prepared as the raw material vinyl chloride product of each sample, a single used product having a uniform mixing ratio of the plasticizer with a clear source was used. The first material piece is obtained by crushing a used hose into a 4 to 6 mm square, and contains 65 to 74% by weight (about 70% by weight on average) of a plasticizer. The hardness obtained by the spring type hardness test was adopted. Hardness about 70H
s (JISA). The second piece of material uses a used agricultural sheet as it is and is 26 to 28% by weight (about 27% on average).
(% By weight) of a plasticizer. As the hardness, a hardness obtained by a spring hardness test was also employed. The hardness is about 80 Hs (JISA). However, since the plasticizer has evaporated for the same new hose and used for agricultural sheets, the exact amount of plasticizer cannot be obtained.
Since the evaporation amount differs depending on the part, the above value has a wide value. The third piece of material is 4-6 mm of used pipe.
It is one that has been pulverized to a corner and does not contain a plasticizer. Hardness is about 100 Hs (JISA).

Samples 1 to 5 are obtained by adding the raw resin to these first to third material pieces as they are or to adjust the ratio of the plasticizer. The comparative samples 1 to 4 are the first
A plurality of 2 or 3 material pieces selected from the third to third material pieces are mixed together. Each of the samples 1 to 5 and the comparative samples 1 to 4 was individually dissolved to obtain a regenerated resin. The results are as follows: ：: good in strength and appearance, ：: relatively good in strength and appearance, Δ: slightly poor in strength and appearance,
X: Inferior in both strength and appearance. As shown in Table 1, the strength and appearance of the recycled resins obtained in Samples 1 to 5 were all good. Therefore, a used vinyl chloride resin having the same (or very close) plasticizer content can be processed in the same manner as a vinyl chloride resin using a raw resin (that is, a non-recycled resin).

On the other hand, in Comparative Samples 1 to 4, the strength and appearance of Comparative Sample 1 were relatively good, and Comparative Samples 2 to 4 were inferior in both strength and appearance. Therefore, it is not possible to knead together raw vinyl chloride products that melt in basically different temperature zones. Here, it is considered that the reason why the comparative sample 1 was relatively good is due to the properties of the plasticizer. As shown in the graph of Table 2, the softening efficiency by the plasticizer tends to be inferior for a soft vinyl chloride resin having a higher plasticizer compounding ratio. The plasticizer exhibits a hardness of 100 Hs (JISA) at 0% by weight as mentioned in the example of the pipe.
That is, it has the hardness of very hard glass. However, although the sheet for agricultural use may be thin, the content of the plasticizer is usually about 30% by weight, and the content is sufficiently flexible at a hardness of about 80 Hs (JISA). In addition, since the hose is thicker than the agricultural sheet, a slightly softer hardness of about 70 Hs (JISA) is required.
A content of about 0% by weight is required.

[0028]

[Table 2]

That is, the plasticizer need not be so large until a certain degree of softness is obtained, but once softened, a large amount of plasticizer is required for softening. Therefore, if there are two types of used vinyl chloride resins and the hardness is high, the difference in the mixing ratio of the plasticizer tends to be difficult to melt at least together. On the other hand, if the two kinds of used vinyl chloride resins are soft vinyl chloride resins, even if there is a considerable difference in the content of the plasticizer, there is no great difference in the hardness, so that it is possible to melt them together. The graph of Table 3 shows the hardness and the range of the hardness that can be melted together at that hardness. For example, a vinyl chloride resin product has a hardness of 100 Hs
In the case of (JISA), the strength and appearance of the recycled resin are basically good even when treated as the same group up to a hardness of ± 4 (+4, that is, up to 96 Hs (JISA) because there is no +4). Also,
With a hardness of 70 Hs (JISA), the strength and appearance of the recycled resin are basically good even when treated as the same group up to a hardness of ± 12. This graph shows the tendency in a general vinyl chloride resin product, and almost similar results were obtained although there was some variation depending on the mixing ratio of the components.

[0030]

[Table 3]

<Example 1> As shown in Table 4, a sample 3 was used as a first group of resin material pieces A, and a second group of resin material pieces B was used.
Was used as Sample 1. The mixing ratio was 50% each. Band heaters 18a to 18d for melting the resin material pieces of the first kneading section 41, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the resin material pieces of the third kneading section 43 Band heater 1 for melting
Tables 5 to 7 show the settings of 8f to 18j. <Example 2> As shown in Table 4, sample 4 was used as the first group of resin material pieces A, and sample 1 was used as the second group of resin material pieces B.
Was used. The mixing ratio was 50% each. Band heaters 18a to 18d for melting the resin material pieces of the first kneading section 41, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the resin material pieces of the third kneading section 43 Band heaters 18f to 18j for melting
Are as shown in Tables 5 to 7.

<Example 3> As shown in Table 4, a sample 5 was used as a first group of resin material pieces A, and a second group of resin material pieces B was used.
Was used as Sample 1. The mixing ratio was 50% each. Band heaters 18a to 18d for melting the resin material pieces of the first kneading section 41, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the resin material pieces of the third kneading section 43 Band heater 1 for melting
Tables 5 to 7 show the settings of 8f to 18j. <Example 4> As shown in Table 4, sample 5 was used as the first group of resin material pieces A and sample 2 was used as the second group of resin material pieces B.
Was used. The mixing ratio was 50% each. Band heaters 18a to 18d for melting the resin material pieces of the first kneading section 41, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the resin material pieces of the third kneading section 43 Band heaters 18f to 18j for melting
Are as shown in Tables 5 to 7.

<Example 5> As shown in Table 4, a sample 4 was used as a first group of resin material pieces A, and a second group of resin material pieces B was used.
Was used as Sample 2. The mixing ratio was 50% each. Band heaters 18a to 18d for melting the resin material pieces of the first kneading section 41, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the resin material pieces of the third kneading section 43 Band heater 1 for melting
Tables 5 to 7 show the settings of 8f to 18j. <Example 6> As shown in Table 4, sample 4 was used as the first group of resin material pieces A and sample 2 was used as the second group of resin material pieces B.
Was used. The mixing ratio is 25% for the first group of resin material pieces A,
The resin material piece B of the second group was 75%. First kneading unit 4
Band heater 18a for melting one resin material piece
Tables 18 to 18d, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the band heaters 18f to 18j for melting the resin material pieces of the third kneading section 43 are shown in Tables 5 to 7. It is as follows. <Example 7> As shown in Table 4, sample 4 was used as the first group of resin material pieces A, and sample 1 was used as the second group of resin material pieces B.
Was used. The mixing ratio is 25% for the first group of resin material pieces A,
The resin material piece B of the second group was 75%. First kneading unit 4
Band heater 18a for melting one resin material piece
Tables 18 to 18d, 35a to 35d for melting the resin material pieces of the second kneading section 42, and the band heaters 18f to 18j for melting the resin material pieces of the third kneading section 43 are shown in Tables 5 to 7. It is as follows.

[0034]

[Table 4]

[0035]

[Table 5]

[0036]

[Table 6]

[0037]

[Table 7]

Further, as another example of the above embodiment, the following configuration is also possible. -In each of the above-described embodiments, the example is described using the extruder 11, but the present invention can be applied to other injection molding machines and calendar processing machines. Further, instead of the die 16 of the extruder 11, a die for molding another molded product may be used. In the above embodiment, the extruder 11 is a single screw 2
Although 0 and 37 are used, screws having two or more axes may be used. Since the resin feeding speed increases as the number of screws increases, the setting in the above embodiment is changed.

The first group of resin material pieces A and the second group of resin material pieces B need not necessarily be a single used vinyl chloride resin. As described above, the content of the plasticizer is given a certain range that does not cause a problem even if the plasticizers are melted together. Further, it is also possible to mix a raw resin or a plasticizer into the first group of resin material pieces A and the second group of resin material pieces B composed of used vinyl chloride resin. This makes it possible to obtain a desired recycled resin product by adjusting the mixing ratio of the plasticizer. In the above embodiment, the first group of resin material pieces A and the second group of resin material pieces B composed of used vinyl chloride-based resin contain a small amount of used resin products having significantly different plasticizer contents. You can do it. For example, it does not mean that a used resin product that the user does not want to mix is mistakenly mixed during the sorting operation of the used vinyl chloride resin product. It is sufficient if this amount is extremely small and the strength and appearance of the recycled resin product can be ignored. -The temperature setting of each heater is an example, and is not limited to the above embodiment. In addition, the present invention can be freely implemented without departing from the gist of the present invention.

[0040]

[Brief description of the drawings]

FIG. 1 is a plan view of an extruder according to an embodiment of the present invention.

[Explanation of symbols]

11 extruder, 17 first cylinder body, 32 second
, A first kneading section, 42 ... a second kneading section, 43 ... a third kneading section.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B29B 17/00 B29B 7/42

Claims (2)

(57) [Claims] 1. A resin material piece mainly composed of a vinyl chloride resin which is separated into a plurality of groups which are melted in different temperature zones, and are kneaded by a kneading apparatus while being heated for each group in a separate heating chamber. A method of producing a vinyl chloride-based regenerated resin in which the molten materials of the respective groups are combined and kneaded under heating in a kneading apparatus to produce a substantially homogeneous vinyl chloride-based regenerated resin. 2. A first resin comprising a hard vinyl chloride resin as a main component.
The group of resin material pieces are introduced into the first heating chamber, kneaded and melted by a kneading device under heating, and the second group of resin material pieces mainly composed of soft vinyl chloride resin are added to the second heating chamber. Into a kneader, and knead and melt the mixture in a kneading machine under heating. The two melted materials are combined, and the two materials are kneaded in a kneading machine under heating to produce a substantially homogeneous vinyl chloride regenerated resin. Method for producing recycled resin.