JP3531657B2 - Molding sheet, method for producing the same, and molded article using the molding sheet - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding sheet, a method for producing the same, and a molded article using the molding sheet,
More specifically, it relates to a molding sheet using a plastic-containing waste material containing a specific thermoplastic resin in a specific content range, a method for producing the molding sheet, and a molded article using the molding sheet.

[0002]

2. Description of the Related Art Generally, automobile interior materials such as carpet materials, felt materials, insulator materials, cushion materials and the like contain thermoplastic resins such as polyolefin resins, polyester resins and polyamide resins. Often
It can be obtained by hot press molding, preheating-cold press molding, extrusion molding, injection molding, integral molding with a skin material, and the like.
However, plastic-containing waste materials such as defective molding materials, poor appearance materials, and trimming scraps are always generated in these manufacturing processes. Also, in recent years, with the promotion of recycling,
A large amount of waste material containing plastic is also recovered from scrapped vehicles.

As an effective utilization method of such waste material containing plastic, trimming waste of a molding core material board containing a high content of a thermoplastic resin is crushed or finely cut, and the core material board is formed by dry extrusion molding. Method of utilizing as a part of raw material, or crushing waste material, separating the crushed material into a fiber-rich portion and a synthetic resin-rich portion, the fiber-rich portion is used as a cushion material or an insulator material, and the resin-rich portion is used. Is used as a part of a dry extrusion molding sheet material.

[0004]

However, in practice, such plastic-containing waste materials are often attached to various skin materials, or waste materials having various compositions generated from various processes are separately managed. Difficult to do,
Further, it is very time-consuming to crush such various waste materials and separate them according to the desired composition. Therefore, in reality, it is often the case that such plastic-containing waste materials are simply discarded or incinerated. The current situation.

Therefore, the present inventor has promptly studied to effectively use such waste material containing plastic by a wet papermaking technique. As a result, a plastic-containing waste material having a solid content of 60% by weight or more of a thermoplastic resin having a melting point of 200 ° C. or less, such as a polyolefin-based resin, is subjected to a usual crushing treatment and mixed with a cellulose fiber, If necessary, add a thermoplastic resin with a melting point of 200 ° C or less to the slurry.
It was found that a sufficiently useful molding sheet can be obtained by wet papermaking the slurry.

[0006] However, as described above, the actual waste material containing plastic has the skin material stuck thereto, and other thermoplastic resin or thermosetting resin having a melting point of more than 200 ° C or other constituent materials are mixed. In general, such a plastic-containing waste material rarely contains a thermoplastic resin having a melting point of 200 ° C. or less at a high solid content of 60% by weight or more. In many cases, the content of the thermoplastic resin having a melting point of 200 ° C. or lower in such a plastic-containing waste material is usually about 20 to 50% by weight in terms of solid content.

In the case of such a plastic-containing waste material having a low melting point of a thermoplastic resin having a melting point of 200 ° C. or less, a sheet obtained even if it is used as a part of a raw material for wet papermaking after being subjected to a usual crushing treatment. However, there were problems such as a decrease in the strength of the product, a lack of the strength after molding, and a decrease in the shape-retaining property.

Therefore, the present inventor has found that the melting point is 200 ° C.
From the viewpoint of environmental protection or economic efficiency, it is effective to use the following plastic-containing waste materials having a low thermoplastic resin content without being discarded or incinerated as a molding sheet or a constituent material of a molded article. We decided that it was the most suitable for the current situation in Japan and decided to make further studies. That is, an object of the present invention is to put into practical use a plastic-containing waste material having a low content of the above-mentioned thermoplastic resin having a melting point of 200 ° C. or less as a molding sheet or a constituent material of a molded product.

[0009]

A molding sheet according to the present invention.
Is a thermoplastic resin having a melting point of 200 ° C. or less in solid content of 20
˜50% by weight and a fibrous component in the plastic-containing waste material having a median diameter of 25-250 μm and 150
A fine powder having a mesh standard sieve passage rate of 30% by weight or more is 10 to 50% by weight as a solid content, and a thermoplastic resin having a melting point of 200 ° C or less is 10 to 60% by weight as a solid content.
A papermaking sheet obtained from a slurry containing 10 to 30% by weight of solids as a solid content, wherein fine powder in the papermaking sheet is attached to the cellulose fibers by a cross-linking adsorption action. Fixed
The sheet is fixed with a polymer-type coagulant to be applied , and the papermaking sheet contains a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 40% by weight or more.

The manufacturing method of the molding sheet according to the present invention is as follows:
A thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 20 to 50
Fine powder obtained by finely pulverizing a plastic-containing waste material containing 50% by weight and a fibrous component so that the median diameter is 25 to 250 μm and the passing rate of the 150-mesh standard sieve is 30% by weight or more is 10 After obtaining a slurry containing 50 to 50% by weight, a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 10 to 60% by weight, and a cellulose fiber in a solid content of 10 to 30% by weight. A polymer-based flocculant which is obtained by adding a polymer-based flocculant to a slurry and fixing the above-mentioned fine powder to the above-mentioned cellulose fiber by a cross-linking adsorption action.
The sheet is made by wet-paper-making in the state of being fixed by fixing to obtain a sheet containing a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 40% by weight or more.

The molded article according to the present invention has a melting point of 200 ° C.
A fine powder having the following thermoplastic resin as solid content of 20 to 50% by weight and the plastic-containing waste material containing a fibrous component having a median diameter of 25 to 250 μm and a 150-mesh standard sieve passage rate of 30% by weight or more. 10 to 10 solids
50% by weight, a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 10 to 60% by weight, and a cellulose fiber in a solid content of 1%.
A papermaking sheet containing a thermoplastic resin having a melting point of 200 ° C. or less, obtained from a slurry containing 0 to 30% by weight, in a solid content of 40% by weight or more, wherein fine powder in the papermaking sheet. Is fixed to the above-mentioned cellulose fiber by a cross-linking adsorption action.
The sheet-shaped sheet is fixed with a polymer-type coagulant and is thermoformed.

The plastic-containing waste materials used in the present invention include carpet materials, felt materials, and insulators.
Materials, such as scrap materials and cushion materials, which are defective due to defective molding or appearance of automobile interior materials, trimming scraps, or scrap materials recovered from scrap cars, can be used, and the content of the thermoplastic resin having a melting point of 200 ° C. or less is 20 to 20 in solid content. Must be 50% by weight. If it is less than 20% by weight, the content of the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet will be insufficient, and as a result, sufficient moldability will not be obtained and the strength of the molded product will be insufficient. On the other hand, if it exceeds 50% by weight, the molding sheet
It is rather preferable to secure the moldability of the molded product and the strength of the molded product, but it is actually necessary to stably secure the required amount of the plastic-containing waste material containing a high amount of the thermoplastic resin having a melting point of 200 ° C. or less. It is difficult and dare to carry out this, because pretreatment such as separation and selection is required.

Further, the plastic-containing waste material used in the present invention must contain a fibrous component. If no fibrous component is contained, the sheet strength before thermoforming may decrease. The kind of the fibrous component may be any kind such as various synthetic fibers, natural fibers, chemical fibers, inorganic fibers or wood fibers, and the content is not particularly limited, but is preferably 5 to 60% by weight in solid content. The fibrous component may be contained as a constituent element of the skin material in the plastic-containing waste material, or as a reinforcing fiber such as a thermoplastic resin molded body or a thermosetting resin molded body in the molded core material. It may be contained.

Further, the plastic-containing waste material used in the present invention has a median diameter of 25 to 250 μm and
It must be pulverized so that the 0 mesh standard sieve passage rate is 30% by weight or more. Median diameter is 2
If it is larger than 50 μm, or if the 150 mesh standard sieve passage rate is less than 30% by weight, the molding sheet is used.
And the strength of the molded product becomes insufficient. Median diameter is 2
If the particle size is smaller than 5 μm, the cost of pulverization treatment is high and it is not suitable in terms of economical efficiency and processing capacity. Further, if it is too fine, the yield during wet papermaking tends to deteriorate.

In general, since fine pulverization treatment is likely to generate heat, when finely pulverizing a plastic-containing waste material containing 20 to 50% by weight of a solid content of a thermoplastic resin having a melting point of 200 ° C. or less used in the present invention, such a case is required. The crushed product is easily melted and fused due to the heat generation. Therefore, it is preferable to use a pulverization method that generates as little heat as possible, that is, a cutter mill or the like, or a wet pulverization method or various low-temperature pulverization methods. When a molding sheet is manufactured by blending a predetermined amount of fine powder of a plastic-containing waste material having a median diameter of 25 to 250 μm and a passing rate of 150 mesh standard sieve of 30% by weight or more, a bundle is formed by dry molding. It tends to occur and it is difficult to obtain a good molding sheet, and wet papermaking is preferable.

By the way, a paper making net used in an ordinary paper making machine has a mesh of about 50 to 150 mesh (opening is about 300 to 1).
00 μm), and the median diameter specified in the present invention is 2
5 to 250 μm, and the standard mesh size of 150 mesh is about 100 μm. The requirement that the passage rate is 30% by weight or more is much smaller than that of a normal papermaking mesh.
It will be finely pulverized so that the amount is at least wt%. Common sense is that pulverizing smaller than the mesh opening of the papermaking network makes it easier for such fine powder to pass through the papermaking network during wet papermaking, resulting in a decrease in yield. Since waste materials generally contain fibrous components such as synthetic fibers and chemical fibers, it is not preferable because it is easy to cause problems such as clogging of the paper making net due to finely pulverized products of such fibrous components.

However, a large number of investigations have made it contrary to the common sense of those skilled in the art that the plastic-containing waste material specified in the present invention has a median diameter of 25 to 250 μm and a passing rate of 150 mesh standard sieve of 30% by weight or more. Crush,
By blending cellulose fiber and a separate thermoplastic resin having a melting point of 200 ° C. or less in a specific blending ratio range and performing wet papermaking, the sheet strength before thermoforming, moldability and strength of the molded article after thermoforming can be improved. It was found that the plastic-containing waste material described above can be used as a constituent material of a molding sheet and a molding.

As the thermoplastic resin having a melting point of 200 ° C. or less used in the present invention, it is most preferable to select one kind or two or more kinds from polyolefin resins such as polyethylene resin and polypropylene resin.
Other resins such as polyurethane-based resins, polyvinyl chloride-based resins, and polyamide-based resins can be used as long as they are thermoplastic resins having a temperature of ℃ or less. The thermoplastic resin may have a fibrous shape, an emulsion shape, a granular shape, or the like. Cellulose used in the present invention
The fiber is appropriately selected from wood pulp, hemp pulp, cotton pulp, various used papers, and other wood fibers.

The median diameter of the plastic-containing waste material containing 20 to 50% by weight of the thermoplastic resin having a melting point of 200 ° C. or less in the slurry in the wet papermaking of the molding sheet of the present invention is 25 to 250 μm. And the content of fine powder having a 150-mesh standard sieve passage rate of 30% by weight or more is 10 to 50% by weight, preferably 20 to 45% by solid content.
Must be% by weight. If it is less than 10% by weight, the compounding amount is too small to sufficiently attain the purpose of effectively utilizing the plastic-containing waste material. If more than 50% by weight, before
As mentioned above, the moldability of the molding sheet and the strength of the molded product are
It is rather preferable to secure, but in practice
Plastic containing a high thermoplastic resin whose temperature is 200 ° C or less
It is difficult to stably secure the required amount of waste materials
In order to do this, pre-processing such as sorting and sorting
It is necessary and unsuitable.

The content of the separately blended thermoplastic resin having a melting point of 200 ° C. or less in the slurry used in the wet papermaking of the molding sheet of the present invention is 10 to 60% by weight, preferably 30 to 50% by solid content. % By weight. If it is less than 10% by weight, the content of the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet will be insufficient, and as a result, sufficient moldability will not be obtained and the strength of the molded product will be insufficient. If it exceeds 60% by weight, the thermoplastic resin added separately is extremely expensive and inferior in economical efficiency as compared with the plastic-containing waste material or cellulose fiber which is another component of the molding sheet of the present invention. become.

When the molding sheet of the present invention is wet-processed, the content of cellulose fibers in the slurry is 10 in terms of solid content.
~ 30% by weight. If it is less than 10% by weight, the papermaking property is deteriorated due to an insufficient amount of cellulose fibers in the slurry, and the strength before heat treatment of the obtained molding sheet is insufficient, resulting in deterioration of handling property. If it exceeds 30% by weight, the melting point in the slurry is 2 due to the excess of cellulose fibers.
It becomes difficult to secure the required amount of the thermoplastic resin of 00 ° C. or less, and to sufficiently mix the plastic-containing waste material specified in the present invention, and due to the excessive amount of cellulose fibers in the obtained molding sheet. However, it is not suitable because it causes deterioration of moldability and deterioration of shape retention of the molded product after molding.

Further, in the slurry, various inorganic fibers such as glass fibers or rock wool fibers for improving the strength of the molded product, papermaking yield improving agents such as fine powder of waste material containing plastic, and for coloring. Synthetic dyes or color pigments of
A drainage improver or the like for stabilizing the papermaking conditions may be contained. Needless to say, a dry or wet paper strengthening agent, a sizing agent, a water resistance agent, a water repellent agent, etc. may be added depending on the application.

In order to produce the molding sheet and molded product according to the present invention using the slurry thus obtained, ordinary papermaking methods and thermoforming methods may be used. That is, for papermaking, the slurry may be supplied onto a papermaking net such as a Fourdrinier, a cylinder or a slanted net, filtered, dehydrated, squeezed and dried. If necessary, two or more paper layers may be superposed by various combination nets, multi-tank nets or various laminators.

Further, a polymer-based coagulant is added to the slurry according to the present invention, and the fine powder in the slurry is converted into cellulose fibers.
If the paper is made in the fixed state, the paper can be made with almost no yield loss and deterioration of water drainage, and a more uniform slurry can be obtained. Therefore, the sheet strength before the thermoforming, the formability, and the molding after the thermoforming can be performed. It is more preferable in that the strength of the product can be further improved. As the polymer-based flocculant used at this time, as long as it exhibits the function of fixing the fine powder in the slurry to the cellulose fiber by a cross-linking adsorption action,
The type is not particularly limited, and any one of polyacrylamide type, polyacrylic acid soda type, polyamine type, polymethacrylic acid type, dicyandiamide type, polyethyleneimine type, chitosan type, cationized starch type, etc. is used. it can. Needless to say, the amount of such a polymer-type flocculant added should be appropriately determined depending on the type of the flocculant, but in the case of the present invention, the fine powder in the slurry is more preferably cellulose.
10 total solids in the slurry to settle on the fiber
The polymer-based coagulant is added in an amount of 0.0 in terms of solid content with respect to 0 part by weight.
It is preferable to add about 05 to 0.5 parts by weight. For thermoforming, conventional hot press molding, preheating-cold press molding, high frequency heat molding, etc. may be used alone or in combination with 2.
It suffices to apply a combination of two or more species.

The molding sheet of the present invention has a melting point of 200.
The thermoplastic resin having a temperature of ℃ or less must be contained in a solid content of 40% by weight or more. If it is less than 40% by weight, sufficient moldability cannot be obtained, and the strength of the obtained molded product becomes insufficient. Further, the molding sheet of the present invention has a solid content of 40% by weight.
The melting point of the thermoplastic resin to be contained above must be 200 ° C. or lower. The molded product of the present invention is obtained by melting the thermoplastic resin contained in the sheet by subjecting the molding sheet of the present invention to conventional heat molding such as preheating-cold press molding. It is obtained by fluidizing, shaping and re-solidifying.

At this time, it is necessary that the thermoforming temperature is not lower than the melting point of the above-mentioned thermoplastic resin, and it is preferable that the temperature is higher than the melting point by 20 to 40 ° C. or more, such as molding efficiency and shaping flexibility. Is often advantageous in terms of. However, since the molding sheet of the present invention contains a predetermined amount of cellulose fiber, the molding temperature is 220 to 250 ° C.
The degree is limited, and at higher temperatures than this, thermal degradation of the cellulose fibers is likely to occur. Therefore, the molding sheet of the present invention
The melting point of the thermoplastic resin to be contained in the resin in a solid content of 40% by weight or more was 200 ° C. or less.

[0027]

The plastic-containing waste material used in the molding sheet and molded product of the present invention contains a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 20 to 50% by weight and a fibrous component. The quality component and other components are not particularly limited,
Generally, polyamide-based or polyester-based synthetic fibers, urethane-based foam resins, natural fibers such as cotton or wool, and chemical fibers are often contained.
Therefore, in short, the molding sheet of the present invention before thermoforming is used.
The strength of the gut is mainly exerted by the cellulose fiber,
The moldability of the molding sheet and the strength of the molded product after thermoforming are mainly exhibited by the thermoplastic resin having a melting point of 200 ° C or lower.

In the present invention, the action of pulverizing the plastic-containing waste material containing 20 to 50% by weight of the solid content of the thermoplastic resin having a melting point of 200 ° C. or less is expected as follows. That is, with respect to the strength of the molding sheet before thermoforming, even if a considerably large amount of the waste material is blended in the papermaking raw material due to pulverization, the inter-cellulosic fibers caused by the waste material in the wet papermaking process The degree of inhibition of binding is reduced,
The sheet strength improving factor that the cellulosic fiber bonds in the obtained molding sheet are strengthened, and various fibrous components in the waste material lose their form as fibers due to pulverization, and a mere powdery material Therefore, it is considered that the sheet strength lowers as if the same situation as that of the high-filler paper is reached.

With respect to the strength of the molded product after thermoforming, the finely pulverized thermoplastic resin having a melting point of 200 ° C. or less contained in the waste material becomes fine, and the heat receiving efficiency at the time of thermoforming is increased and -The number of contact points with other components in the gut also increases, the moldability and strength development by melting and re-solidification are more effectively performed, and the strength improvement factor due to pulverization, most of the waste materials are Components other than the thermoplastic resin having a melting point of 200 ° C. or less, that is, the objects to be bonded by the melting / resolidifying function of the thermoplastic resin having a melting point of 200 ° C. or less are also finely pulverized during thermoforming. When thermoforming a molding sheet obtained by using the fine powder of such waste material, the fine powdery substances and the fine powdery substance and the molding sheet are used.
It is considered that the number of contact points with other constituents in the alloy increases, and that the thermoplastic resin having a melting point of 200 ° C. or less is not sufficiently supplied to such contact points, which is a factor of strength reduction.

In fact, in the present invention, as can be seen from Examples and Comparative Examples described later, both the strength of the molding sheet before thermoforming and the strength of the molded article after thermoforming are greatly improved. This is because the thermoplastic resin having a melting point of 200 ° C. or less has a solid content of 20.
Even if it is a plastic-containing waste material containing only up to 50% by weight, the waste material has a median diameter of 25 specified in the present invention.
To 250 μm and finely pulverized so that the 150 mesh standard sieve passage rate is 30% by weight or more, and compounded with cellulose fiber and another thermoplastic resin having a melting point of 200 ° C. or less in a specific compounding ratio range, and wet papermaking Then, by thermoforming the obtained sheet, a molding sheet before thermoforming and a molded article after thermoforming, out of two sets of contradictory factors for the strength before and after thermoforming described above. In each case, it is considered that the strength improving factor overcomes the strength lowering factor and acts more strongly.

Some further consideration will be added to this point. From the observation of the waste plastic material used in the present invention and the fine powder thereof, the median diameter of 25 to
The finely pulverized product is 250 μm and is finely pulverized so that the passing rate of the 150-mesh standard sieve is 30% by weight or more.
The former is mainly a crushed product of a thermoplastic resin having a melting point of 200 ° C. or lower, and the latter is mainly composed of a mixture of a fine powder composition passing through a 0 mesh standard sieve and a composition having a relatively larger size. It is presumed to be a crushed product of synthetic fiber, natural fiber or chemical fiber, which is another component in the plastic-containing waste material. Then, all or most of the thermoplastic resin having a melting point of 200 ° C. or less in the plastic-containing waste material used in the present invention is pulverized to a size not more than a size that passes through a 150-mesh standard sieve. In the molding slurry, the inhibition of cellulosic fiber-to-fiber bonding due to such waste material fine powder is suppressed to a minimum, the heat receiving efficiency of the thermoplastic resin from the waste material at the time of thermoforming is increased, and in the sheet. It is considered that the contact points with other constituents of the resin also increased and the moldability by melting and re-solidification and the function of expressing the strength of the molded product were maximized.

On the other hand, since all or most of the various fiber components in the waste material still have a relatively large size, that is, the form of the fiber is maintained, such fiber components are contained in the molding sheet before thermoforming. Contributes to maintaining and improving strength,
The contact point between such fiber components or the contact between the fiber components and other components in the sheet does not increase so much, and the moldability by melting and re-solidifying the thermoplastic resin having a melting point of 200 ° C. or less during thermoforming. It is considered that the strength development function of the molded product is fully utilized.

[0033]

EXAMPLES Next, the present invention will be described more specifically based on the following examples. The measurement of each item in this example was carried out by the following methods. Thickness and density: According to JIS P-8118. Bending strength: According to JIS A-5907. Median diameter and 150 mesh standard sieve passage rate:
Sieving was performed with a total of 7 stages of 14, 32, 60, 100, 150, 200, 325 mesh sieves, a sieve passage curve was drawn, and the value at which the passage rate was 50% was taken as the median diameter. Further, the 150-mesh standard sieve passage rate was obtained from the total of the 325-mesh passage amount, the 325-mesh sieve remaining amount, and the 200-mesh sieve remaining amount.

Example 1 About 30% by weight of polypropylene resin (melting point: about 160 ° C.)
In addition to this, a cutter mill is used for waste material of automobile trunk interior materials, which is composed of about 50% by weight of polyethylene terephthalate resin (melting point: about 250 ° C) and about 20% by weight of natural fiber (cotton and wool). Finely pulverized with a median diameter of 14
0 μm, and the passing rate of the 150 mesh standard sieve is 43
A fine powder was obtained, which was% by weight. The fine powder thus obtained is mixed with a kraft waste paper, mechanical wood fiber and fibrous polyethylene resin (melting point: about 130 ° C .; the same applies hereinafter) and disintegrated (compounding ratio is fine powder of waste material containing plastic as solid content). 35% by weight, recycled waste paper was 10% by weight in solid content, mechanical wood fiber was 10% by weight in solid content, and fibrous polyethylene resin was 45% by weight in solid content.

Next, the total solid content of the obtained slurry was 10
To 0 parts by weight, 3 parts by weight of a sulfuric acid band and 0.04 parts by weight of a polyacrylamide type coagulant in solid content were added,
Cross-linking adsorption of fine powder in slurry to cellulose fiber
In the state of being fixed with the polymer-type coagulant which is fixed by the above method, a square test paper machine was used to make paper using a 100 mesh hand making machine, and the sheet was pressed and dried to obtain a molding sheet A. The thickness, density and bending strength of the molding sheet A were measured, and the results were used to determine the content of each component in the slurry and the content of the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet. The rate is shown in Table 1. Next, 20 sheets of molding sheet A are used.
After preheating at 0 ° C for 1 minute, cold press (contact pressure 10k
g / cm ² , for 1 minute) to obtain a molded product A. Molded product A
The thickness, the density and the bending strength were measured, and the results are also shown in Table 1.

Example 2 The same as Example 1 except that the fine pulverization conditions of the plastic-containing waste material were changed to use a fine powder having a median diameter of 50 μm and a 150-mesh standard sieve passage rate of 64% by weight. Similarly, molding sheet B and molding B
Got Regarding the molding sheet B and the molded product B, the thickness,
The density and flexural strength were measured, and the content of each component in the slurry and the content of the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet are shown in Table 1.

Example 3 In Example 1, the mixing ratio in the mixing and disaggregation was as follows: waste material containing plastic was 45% by weight in solid content, waste kraft paper was 10% by weight in solid content, mechanical wood fiber was 10% by weight in solid content, fiber Polyethylene resin in solid content is 35
A molding sheet C and a molded product C were obtained in the same manner as in Example 1 except that the content was changed to wt%. The thickness, density and bending strength of the molding sheet C and the molded product C were measured, and the content of each component in the slurry and the melting point of the thermoplastic resin of 200 ° C. or less in the molding sheet were measured. It is shown in Table 1 together with the content rate.

Example 4 In Example 2, the blending ratio in mixing and disaggregation was as follows: waste material containing plastic was 45% by weight in solid content, waste kraft paper was 10% by weight in solid content, mechanical wood fiber was 10% by weight in solid content, fiber Polyethylene resin in solid content is 35
A molding sheet D and a molded product D were obtained in the same manner as in Example 1 except that the content was changed to wt%. The thickness, density and bending strength of the molding sheet D and the molded product D were measured, and the content of each component in the slurry and the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet were measured. It is shown in Table 1 together with the content rate.

Example 5 About 45% by weight of polypropylene resin (melting point: about 160 ° C.)
Waste material of automobile interior carpet material containing about 20% of natural fibers (cotton and wool) is pulverized by a pulverizer to have a median diameter of 230 μm and a passing rate of 150 mesh standard sieve of 42% by weight. A fine powder was obtained. The fine powder thus obtained is mixed with a kraft waste paper, mechanical wood fiber and powdered polypropylene resin (melting point: about 160 ° C .; the same applies hereinafter) in a disintegrator. 25% by weight, recycled kraft paper has a solid content of 12.5% by weight, mechanical wood fiber has a solid content of 12.5% by weight, and powdered polypropylene resin has a solid content of 50% by weight. did.

Then, 3 parts by weight of a sulfuric acid band and 0.04 parts by weight of a solid content of a polyacrylamide-based coagulant were added to 100 parts by weight of a solid content of the obtained slurry, and a fine powder in the slurry was added to a cellulose fiber. While firmly fixed to the sheet, a square test paper machine was used to make paper using a 100-mesh hand making machine, and the sheet was pressed and dried to obtain a molding sheet E. Next, the molding sheet E was preheated and cold pressed under the same conditions as in Example 1 to obtain a molded product E. The thickness, density, and bending strength of the molding sheet E and the molding E were measured, and the content of each component in the slurry and the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet were measured. Table 1 together with the content rate
It was shown to.

Comparative Example 1 In Example 1, the same waste material as the interior material of the automobile trunk used in Example 1 was crushed (rotary cutter).
And a pulverized product having a median diameter of 830 μm and a 150-mesh standard sieve passage rate of 13% by weight were used to obtain a molding sheet F and a molded product F in the same manner as in Example 1. . Regarding the molding sheet F and the molded product F,
The thickness, density and flexural strength were measured, and the results are shown in Table 1 together with the content of each component in the slurry and the content of the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet.

Comparative Example 2 In Example 1, a waste material of an automobile interior carpet material containing polyethylene terephthalate resin (melting point of about 250 ° C.) as a main component and containing no thermoplastic resin having a melting point of 200 ° C. or less was crushed. Example 1 except that the pulverized product was pulverized with a (rotary cutter) and had a median diameter of 740 μm and a 150-mesh standard sieve passage rate of 15% by weight.
A molding sheet G and a molded product G were obtained in the same manner as in. The thickness, density and bending strength of the molding sheet G and the molding G were measured, and the content of each component in the slurry and the melting point of the thermoplastic resin of 200 ° C. or less in the molding sheet were measured. It is shown in Table 1 together with the content rate.

Comparative Example 3 Polyamide resin (melting point: about 230 ° C.) used in Example 1
Was used as a main component, and a waste material of an automobile interior carpet material having a melting point of 200 ° C. or less and containing no thermoplastic resin was pulverized by a pulverizer (rotary cutter) to have a median diameter of 220 μm.
A molding sheet H and a molded product H were obtained in the same manner as in Example 1 except that fine powder having a 150 mesh standard sieve passage rate of 41% by weight was used. The thickness, density and flexural strength of the molding sheet H and the molded product H were measured, and the content of each component in the slurry and the thermoplastic resin having a melting point of 200 ° C. or less in the molding sheet were measured. Table 1 together with the content rate
It was shown to.

Comparative Example 4 In Comparative Example 1, the mixing ratio in the mixing disaggregation was 45% by weight of the plastic-containing waste material, 10% by weight of the waste kraft paper, and 10% by weight of the mechanical wood fiber. Fibrous polyethylene resin has a solid content of 3
A molding sheet I and a molded product I were obtained in the same manner as in Comparative Example 1 except that the content was adjusted to 5% by weight. The thickness, density and bending strength of the molding sheet I and the molded article I were measured, and the content of each component in the slurry and the molding sheet were measured.
It is shown in Table 1 together with the content of the thermoplastic resin having a melting point of 200 ° C. or less in the resin.

Comparative Example 5 In Comparative Example 2, the mixing ratio in the mixing disaggregation was 45% by weight for the plastic-containing waste material, 10% by weight for the solid waste kraft paper, and 10% by weight for the mechanical wood fiber. Fibrous polyethylene resin has a solid content of 3
A molding sheet J and a molded product J were obtained in the same manner as in Comparative Example 2 except that the content was 5% by weight. The thickness, density, and bending strength of the molding sheet J and the molding product J were measured, and the content of each component in the slurry and the molding sheet were measured.
It is shown in Table 1 together with the content of the thermoplastic resin having a melting point of 200 ° C. or less in the resin.

Comparative Example 6 In Example 1, the mixing ratio in the mixing and disaggregation was such that the plastic-containing waste material had a solid content of 65% by weight, the waste kraft paper had a solid content of 10% by weight, and the mechanical wood fiber had a solid content of 10% by weight. Fibrous polyethylene resin is 1 in solid content
A molding sheet K and a molded product K were obtained in the same manner as in Example 1 except that the content was adjusted to 5% by weight. The thickness, density and bending strength of the molding sheet K and the molded product K were measured, and the content of each component in the slurry and the molding sheet were measured.
It is shown in Table 1 together with the content of the thermoplastic resin having a melting point of 200 ° C. or less in the resin.

[0047]

[Table 1]

[0048]

EFFECTS OF THE INVENTION Examples 1 to 5 and Comparative Examples 1 to 6 described above.
As can be seen from the above, even if the present invention is a plastic-containing waste material that contains a thermoplastic resin having a melting point of 200 ° C. or less at a low solid content of 20 to 50% by weight, such a plastic-containing waste material is one of the raw materials. It is possible to obtain a molding sheet and a molded product that can be effectively utilized as a part, have excellent moldability and strength, and that can be sufficiently put to practical use, and a method for producing them can be easily obtained.

For example, Examples 1, 2 and Comparative Examples 1, 2,
Comparing No. 3 and Examples 3 and 4 with Comparative Examples 4 and 5, respectively, in Examples of the present invention, the content of the thermoplastic resin having a melting point of 200 ° C. or less, which can secure a necessary amount relatively easily, is a solid content. 20 to 50% by weight of the plastic-containing waste material has a median diameter range specified in the present invention and 150
A fine powder having a mesh standard sieve passage rate range is used, and the fine powder, cellulose fiber and a separate thermoplastic resin having a melting point of 200 ° C. or less are made into a slurry having a mixture rate range specified in the present invention. Since the obtained molding sheet is thermoformed, the strength of the molding sheet before thermoforming is 1.3 to 2.1 times and the strength of the molded article after thermoforming is higher than that of the comparative example. 1.2
It can be seen that each is improved to 1.9 times.

That is, according to the present invention, the moldability and strength inherent in a thermoplastic resin having a melting point of 200 ° C. or less in a plastic-containing waste material having a low content of the thermoplastic resin having a melting point of 200 ° C. or less, which has been difficult to put into practical use until now, The present invention provides a very effective and rational use method of maximizing the expression function of the waste material and suppressing the adverse effects caused by other components in the waste material to a minimum. It is possible to put it into practical use as a constituent material for molded products and molded articles. In particular, the strength of the molding sheet before thermoforming
However, due to pulverization, a considerably large amount of
Even if waste material is mixed, it will be treated as such in the wet papermaking process.
The degree of inhibition of the cellulosic fiber-to-fiber bonds caused by the reduction is reduced.
And the bonding between the cellulose fibers in the resulting molding sheet is
To be strengthened. Also, for the strength of the molded product after thermoforming
Is a melting point of 200 ℃ or less contained in the waste material by fine pulverization.
The thermoplastic resin is finer and the heat receiving efficiency during thermoforming is increased.
Larger contact points with other components in the sheet
However, the moldability and strength development by melting and re-solidifying are more effective.
It is done at the end.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI B29K 105: 26 B29K 105: 26 201: 00 201: 00 C08L 1:00 C08L 1:00 (58) Fields investigated (Int.Cl . ⁷ , DB name) C08J 5/04-5 / 10,5 / 24 B29B 11 / 16,15 / 08-15/14

Claims (7)

(57) [Claims] 1. A median diameter of a plastic-containing waste material containing a thermoplastic resin having a melting point of 200 ° C. or less at a solid content of 20 to 50% by weight and a fibrous component and a median diameter of 25 to 250 μm, and a passage rate of 150 mesh standard sieve of 30. Fine powder of 10% to 50% by weight in solid content and a melting point of 200%
10-60% by weight of a thermoplastic resin at a temperature of ℃ or less,
A papermaking sheet obtained from a slurry containing 10 to 30% by weight of cellulose fiber as a solid content, wherein fine powder in the papermaking sheet is cross-linked and adsorbed to the cellulose fiber. Action
Fix with a polymer-based coagulant
Is, and該抄Zoshi - DOO molding sheet characterized in that it contains a melting point 200 ° C. or less of the thermoplastic resin in a solid content of 40 wt% or more - and. 2. A plastic-containing waste material containing a thermoplastic resin having a melting point of 200 ° C. or less at a solid content of 20 to 50% by weight and a fibrous component, a median diameter of 25 to 250 μm, and a 150 mesh standard sieve passage rate of 30. Fine powder obtained by finely pulverizing to have a solid content of 10 to 50% by weight or more.
% By weight, 10 to 60% by weight of thermoplastic resin having a melting point of 200 ° C. or less in solid content, and 10 to 10% by weight of cellulose fiber in solid content.
After obtaining a slurry containing 30% by weight, the slurry
A polymer-type flocculant is added to the above, and the above-mentioned fine powder is fixed to the above-mentioned cellulose fiber by a cross-linking adsorption action.
A sheet for molding which is characterized in that a sheet is obtained by wet papermaking in a state of being fixed with a molecular flocculant and containing a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 40% by weight or more.
Manufacturing method. 3. A plastic-containing waste material containing a thermoplastic resin having a melting point of 200 ° C. or less in a solid content of 20 to 50% by weight and a fibrous component having a median diameter of 25 to 250 μm and a passage rate of 150 mesh standard sieve of 30. Fine powder of 10% to 50% by weight in solid content and a melting point of 200%
10-60% by weight of a thermoplastic resin at a temperature of ℃ or less,
A papermaking sheet comprising a thermoplastic resin having a melting point of 200 ° C. or less, obtained from a slurry containing 10 to 30% by weight of cellulose fiber in a solid content, and containing 40% by weight or more in a solid content of the thermoplastic resin. The fine powder in the papermaking sheet is the cellulose fiber ,
Determined with a polymeric flocculant that fixes by cross-linking adsorption
A molded article which is dressed and is formed by thermoforming the paper sheet. 4. The molding sheet according to claim 1, wherein the thermoplastic resin having a melting point of 200 ° C. or lower is a polyolefin resin. 5. The molded product according to claim 3, wherein the thermoplastic resin having a melting point of 200 ° C. or lower is a polyolefin resin. 6. The molding sheet according to claim 1, wherein the plastic-containing waste material is a waste material of an automobile interior material. 7. The molding according to claim 3, wherein the plastic-containing waste material is a waste material for automobile interior materials.
Thing .