JP2001026652A - Preparation of resin mixture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stable preparation process of a uniform resin mixture with little dispersion which gives a uniform resin composition or resin molded product with little dispersion by melt kneading this mixture. SOLUTION: In a preparation process of a resin mixture comprising two or more particulate resins and one or more powdery resin, two or more particulate resins are pre-mixed in a rotary mixer to form a pre-mixture which is subsequently mixed with one or more powdery resin. Here, two or more particulate resins are pre-mixed in the presence of 0.01 to 10 wt.% antistatic agent against the total weight of the pre-mixture. Furthermore, the pre-mixing of two or more particulate resins is conducted by rotating the rotary mixer 250 to 1,000 times at a rotation speed of 15 to 45 rotation/min.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a resin mixture, and more particularly, to a method for producing a resin mixture having a small variation and stably.
The present invention relates to a method for producing a resin mixture, which can make a resin composition or a resin molded product obtained by melt-kneading the mixture uniform with a small variation.

[0002]

2. Description of the Related Art Conventionally, when producing a resin composition or a resin molded product in which two or more kinds of resins are used in combination and additives are added thereto, the two or more kinds of resin granules and one or more kinds of additives are used. And the like, a powdered material, and the like, a mixture is formed into a mixture by a mixer, and then the mixture is charged into a molding machine and melt-kneaded to directly obtain a resin composition or a resin molded product, or the mixture is extruded. After being melted and kneaded, extruded into strands and cut into pellets to form a granular resin composition,
Any of the methods of charging the granules to a molding machine and melt-kneading to obtain a resin molded product has been adopted, and the method of producing the mixture at that time is to change the melt-kneading order of the resin used in combination. Generally, two or more kinds of resin granules to be used in combination and one or more kinds of powders such as additives are simultaneously charged into a mixer and mixed except for changing the mixing order. I have.

However, according to studies by the present inventors, in the conventional mixing method, mixing under high mixing conditions does not always result in obtaining a uniform mixture.
At times, it has been found that variations and uniformity in the resulting mixture are rather reduced, especially when the molded article is subjected to a stretching step such as a stretched film or a monofilament, resulting from the non-uniformity of the mixture. Since the non-uniformity of the molded article can be a fatal problem, the inventors have sought to further homogenize these mixtures.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and therefore, the present invention can stably produce a uniform resin mixture having a small variation. It is another object of the present invention to provide a method for producing a resin mixture, which can make a resin composition or a resin molded product obtained by melt-kneading the mixture less uniform and uniform.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to achieve the above object, and as a result, the resin granules are charged by the accumulation of static electricity generated by friction or the like during the mixing operation, and the resin granules are charged. It has been found that the uniform mixing of the powders is reduced, and that the uniform mixing of the powders such as additives is deteriorated. Therefore, at least the powders should be mixed after the resin granules are mixed. The present invention has been found to be necessary, and the present invention has been completed. That is, the present invention relates to the production of a mixture of two or more kinds of resin granules and one or more kinds of powders. A gist of the present invention is a method for producing a resin mixture in which the resin granules are premixed with a rotary container type mixer to form a premix, and then the premix is mixed with one or more powders.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION In the method for producing a resin mixture of the present invention, the granular resin is not particularly limited, but preferably at least one of two or more resins is more preferable. It is preferable that all of two or more are thermoplastic resins. As the thermoplastic resin,
Specifically, for example, polyolefin resin, styrene resin, polyvinyl chloride resin, polyamide resin, polycarbonate resin, polyester resin, polyphenylene ether resin, acrylic resin, fluorine resin and the like, Among them, a polyamide resin, a polycarbonate resin, or a polyester resin is preferable, and a polyamide resin is particularly preferable.

Here, as the polyamide resin,
A polymer of a lactam having three or more rings, a polymer of an amino acid, a polycondensate of a diamine and a dicarboxylic acid, or a copolymer thereof, specifically, as the lactam, for example, , Butyrolactam, δ-valerolactam, ε-caprolactam, enantholactam, ω-lauryl lactam and the like. Specific examples of the amino acids include, for example, 6-aminocaproic acid, 7-aminoheptanoic acid, 8-amino Octanoic acid, 9-aminononanoic acid, 1
1-aminoundecanoic acid, 12-aminododecanoic acid and the like, and specific examples of the diamines include, for example,
1,4-butanediamine, 1,5-pentanediamine,
Aliphatic diamines such as 1,5-hexanediamine, 1,6-hexanediamine, 1,9-nonanediamine, 1,11-undecadiamine, 1,12-dodecanediamine, α, ω-diaminopolypropylene glycol; 3
-Or 1,4-bis (aminomethyl) cyclohexane,
Examples of the dicarboxylic acids include alicyclic diamines such as bis (p-aminocyclohexylmethane) and aromatic diamines such as m- or p-xylylenediamine. Specific examples of the dicarboxylic acids include glutaric acid, adipic acid, and suberin. Examples include aliphatic dicarboxylic acids such as acid, sebacic acid and dodecane diacid, alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid, and aromatic dicarboxylic acids such as terephthalic acid and isophthalic acid.

[0008] Among them, copolymer nylon or semi-aromatic nylon in which ε-caprolactam or 6-aminocaproic acid is contained in an amount of 60 to 95% by weight of all constituent components is preferable. , Copolymer of ε-caprolactam or 6-aminocaproic acid and ω-lauryl lactam or 12-aminododecanoic acid (6/12 nylon), ε-caprolactam or 6-aminocaproic acid, 1,6-hexanediamine and adipic acid (6/66 nylon), ε-caprolactam or 6-66
Copolymer of aminocaproic acid, 1,6-hexanediamine and sebacic acid (6/610 nylon), ε-caprolactam or copolymer of 6-aminocaproic acid, 1,6-hexanediamine and terephthalic acid (6 / 6T nylon) and the like, and 6/66 nylon is particularly preferred. Also, as the latter semi-aromatic nylon, specifically,
Nylon composed of m-xylylenediamine and adipic acid (MXD6 nylon), copolymerized nylon of 1,6-hexanediamine, isophthalic acid and terephthalic acid (6I /
6T nylon) and the like, and particularly preferred is 6I / 6T nylon.

The polycarbonate resin may be a homopolymer or a homopolymer obtained by a phosgene method of reacting a dihydroxydiaryl compound with phosgene, or a transesterification method of reacting a dihydroxydiaryl compound with a carbonate such as diphenyl carbonate. As the dihydroxydiaryl compound which is a copolymer, specifically, for example, bis (4-hydroxyphenyl) methane, 1,1-bis (4′-hydroxyphenyl) ethane, 2,2-bis ( 4'-hydroxyphenyl) propane, 2,2-bis (4'-hydroxy-
3′-methylphenyl) propane, 2,2-bis (4 ′
-Hydroxy-3'-t-butylphenyl) propane,
2,2-bis (4'-hydroxy-3'-bromophenyl) propane, 2,2-bis (4'-hydroxy-
3 ', 5'-dibromophenyl) propane, 2,2-bis (4'-hydroxy-3', 5'-dichlorophenyl) propane, 2,2-bis (4'-hydroxyphenyl) butane, 2,2- Bis (hydroxyaryl) alkanes such as bis (4'-hydroxyphenyl) octane and bis (4-hydroxyphenyl) phenylmethane;
Bis (hydroxyaryl) cycloalkanes such as 1,1-bis (4′-hydroxyphenyl) cyclopentane and 1,1-bis (4′-hydroxyphenyl) cyclohexane, 4,4′-dihydroxydiphenyl ether,
Dihydroxy diaryl ethers such as 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether;
4,4'-dihydroxydiphenyl ketone, 4,4'-
Dihydroxydiaryl ketones such as dihydroxy-3,3'-dimethyldiphenyl ketone; dihydroxydiaryl sulfides such as 4,4'-dihydroxydiphenyl sulfide and 4,4'-dihydroxy-3,3'-dimethyldiphenyl sulfide; 4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxy-
Dihydroxydiarylsulfoxides such as 3,3'-dimethyldiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfone, 4,4'-dihydroxy-
Dihydroxydiarylsulfones such as 3,3′-dimethyldiphenylsulfone;
Bis (4'-hydroxyphenyl) propane is preferred.

The polyester resin is a polycondensate of a dicarboxylic acid and a diol. Specific examples of the dicarboxylic acid include terephthalic acid, phthalic acid, isophthalic acid and phenylenedioxy acid. Dicarboxylic acid, 2,2′-diphenyldicarboxylic acid, 4,
4'-diphenyl dicarboxylic acid, 4,4'-diphenyl ether dicarboxylic acid, 4,4'-diphenyl ketone dicarboxylic acid, 4,4'-diphenoxyethane dicarboxylic acid, 4,4'-diphenyl sulfone dicarboxylic acid, 2,
Aromatic dicarboxylic acids such as 6-naphthalenedicarboxylic acid,
Aliphatic dicarboxylic acids such as hexahydroterephthalic acid and hexahydroisophthalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, etc. As the diols, specifically, for example, ethylene glycol, propylene glycol, trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, octamethylene glycol, decamethylene glycol, neopentyl glycol, diethylene glycol, polyethylene Glycols, aliphatic diols such as polytetramethylene ether glycol, 1,2-cyclohexanediol, 1,4-
Alicyclic diols such as cyclohexanediol, 1,1-cyclohexanedimethylol, and 1,4-cyclohexanedimethylol, xylylene glycol, 4,4′-dihydroxybiphenyl, 2,2-bis (4′-hydroxyphenyl) propane 2,2-bis (4′-β-hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bis (4-β-hydroxyethoxyphenyl) sulfonic acid, 2,2-bis (4′-hydroxy Aromatic diols such as ethylene oxide adduct or propylene oxide adduct of phenyl) propane; and hydroxycarboxylic acids such as glycolic acid, p-hydroxybenzoic acid, and p-β-hydroxyethoxybenzoic acid; Alkoxycarboxylic acid, and stearyl alcohol, Monofunctional components such as benzyl alcohol, stearic acid, benzoic acid, t-butylbenzoic acid, and benzoylbenzoic acid; tricarballylic acid, butanetricarboxylic acid, hexanetricarboxylic acid, cyclohexanetricarboxylic acid, trimellitic acid, trimesic acid, and naphthalenetricarboxylic acid; Octanetetracarboxylic acid, pyromellitic acid, trimethylolethane, trimethylolpropane, glycerol, pentaerythritol, one or two or more trifunctional or higher polyfunctional components such as gallic acid may be used as a copolymer component. Good.

Specifically, for example, polyethylene terephthalate, polyethylene naphthalate, polypropylene terephthalate, polybutylene terephthalate, polyhexamethylene terephthalate, polycyclohexane dimethylene terephthalate, poly (ethylene terephthalate / ethylene isophthalate), poly (butylene terephthalate) Butyrendecadioate) and the like.

In the present invention, the two or more kinds of resin granules to be mixed may be different types of the above-mentioned various resins, or may be different types or different components of the same type even in the same type. When various physical properties are different even if the components are the same (for example, when the melting points are different by 5 ° C. or more),
Further, they are the same, and all the cases where there are a plurality of granular resin to be mixed, for example, when only the kind of the added additive is different, and the amount of the mixing does not matter.

Here, the granular material of the resin refers to a column having a diameter of about 2 to 4 mm and a length of about 2.5 to 4 mm,
It refers to pellets such as elliptic cylinders, chips, or spheres having a diameter of about 2 to 4 mm.

In the method for producing a resin mixture of the present invention, the powdery material typically includes, for example, a plasticizer such as ethylene bisstearic acid amide, stearic acid, and caprolactam; and a coloring agent such as a pigment and a dye. , Calcium carbonate,
Nucleating agents such as inorganic fine particles such as titania, alumina, silica, talc, kaolin, and clay; antiblocking agents; or fillers; phenolic, phosphorus, sulfur, and amine antioxidants; benzophenones; benzotriazole Compounds, hindered amine-based, salicylate-based ultraviolet absorbers, phosphorus-based, bromine-based flame-retardants, antimony trioxide and other flame-retardant aids, and so-called compounds used as resin additives. Also, powdery substances such as the resins mentioned as the above-mentioned granular resin can be mentioned as an object.

Here, the powdery material preferably has a size of about 10 mesh (about 1600 μm or less) through a Tyler sieve, and 30 mesh (about 500 μm).
m or less), and more preferably about 50 mesh (about 300 μm or less).

According to the method for producing a resin mixture of the present invention, in producing a mixture of two or more kinds of the above-mentioned resin granules and one or more kinds of the above-mentioned powdery bodies, first, two or more kinds of the above-mentioned resin granules are rotated. The mixture is premixed in a container type mixer to form a premix.

Here, as a rotary container type mixer, a container for accommodating a substance to be mixed is rotated and mixed.
The shape of the container is cylindrical and its transverse section is the axis of rotation, and the shape of the container is a double frustum of cones with two truncated cones superimposed on the large diameter side, and the overlapping surface is the axis of rotation. The container shape is a cubic shape, and the line connecting the opposing apex corners is used as the axis of rotation, and the container shape is a V-shaped cylindrical shape in which two cylinders are joined in a V-shape. Rotating about a plane of 45 degrees with respect to the cylindrical axis as a rotation axis.

In the preliminary mixing by the rotary container type mixer, the rotation speed of the rotary container type mixer is preferably 15 to 45 times / minute, more preferably 20 to 40 times / minute, and more preferably 25 to 40 times / minute. It is particularly preferred that the rate be 35 times / minute.
Further, the total amount of rotation is preferably from 250 to 1000 times, more preferably from 300 to 800 times,
It is particularly preferable that the number be 0 to 600 times. Further, the amount of the mixture with respect to the volume of the rotating container is preferably 20 to 60% by volume, more preferably 30 to 50% by volume,
It is particularly preferred to be 30 to 50% by volume. Rotational speed,
If the total rotation amount and the volume occupied by the mixture are out of the above ranges, it tends to be difficult to achieve the object of the present invention.

In the premixing according to the present invention, it is preferable to eliminate static electricity generated by friction between the resins and to prevent electrification due to accumulation of the static electricity. Although there are methods such as attachment and spraying of ionized air or water vapor, it is particularly preferable to add an antistatic agent together with two or more kinds of the resin granules and perform premixing in the presence thereof.

Here, the antistatic agent is -10
Liquid at a temperature in the range of from 0 to 120 ° C, and having a viscosity of about 0.01 to 10 m ² near room temperature (about 10 to 30 ° C).
/ S, more preferably 0.1-8 m ² / s, especially 0.2-5 m
Organic compounds that are ² / sec are preferred.

Specific examples of the antistatic agent include ethylene glycol, polyoxyalkylene monolaurate, polyoxyalkylene sorbitan monolaurate, and N-alkylaryl sulfonamide. N-alkylarylsulfonamides are preferred, and particularly N-alkyl represented by the following general formula:
Alkylaryl sulfonamides are preferred.

[0022]

Embedded image

Wherein R ¹ is an alkyl group having 1 to 10 carbon atoms or a cycloalkyl group having 5 to 8 carbon atoms, and R ² is a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or 5 carbon atoms. ~
8 represents a cycloalkyl group, and the benzene ring may have a substituent. ]

Here, the alkyl group of R ¹ and R ² preferably has 1 to 6 carbon atoms, and has 2 to 2 carbon atoms.
4 is more preferred. Also, R ² is preferably a hydrogen atom.

Specific examples of the N-alkylarylsulfonamide represented by the above general formula include, for example, N-ethylbenzenesulfonamide, Nn-propylbenzenesulfonamide, Nn-butylbenzenesulfonamide, , N-dimethylbenzenesulfonamide, N,
N-methylethylbenzenesulfonamide, N, N-methyl-n-propylbenzenesulfonamide, N, N-
Diethylbenzenesulfonamide, N, N-ethyl-n
-Propylbenzenesulfonamide, N, N-di-n-
Propylbenzenesulfonamide, N, N-di-n-butylbenzenesulfonamide, N-cyclopentylbenzenesulfonamide, N-cyclohexylbenzenesulfonamide, Nn-butyltoluenesulfonamide,
N-cyclohexyltoluenesulfonamide and the like can be mentioned.

The amount of these antistatic agents in the premix is preferably from 0.01 to 10% by weight, more preferably from 0.05 to 1% by weight, based on the total weight of the premix. It is particularly preferred that the content be 1 to 0.5% by weight.
If the amount of the antistatic agent is less than the above range, the obtained resin mixture tends to be uneven or non-uniform, while if the amount is more than the above range, the moldability of the obtained resin mixture tends to decrease.

In the method for producing a resin mixture of the present invention, following the above-mentioned premixing of two or more kinds of resin granules, the obtained premix and one or more kinds of the above-mentioned powdery bodies are mixed.

As the mixer used for the mixing here, in addition to the same rotary container type mixer used for the preliminary mixing, the container itself for accommodating the material to be mixed is fixed, and a screw or a stirring blade provided in the container is used. A fixed container type mixer that mixes by rotation of can be used, but it is preferable to use the same rotary container type mixer used for the premixing, and the rotation speed, the total rotation amount, and the The volume occupied, etc.
It is preferable to set the same range as in the premixing.

In the present invention, the amount of the powdery material is
It is preferably 0.01 to 30% by weight, more preferably 0.05 to 20% by weight of the total weight of the mixture,
It is particularly preferred to be 0.1 to 10% by weight.

When further adding a liquid or granular additive which does not form a powdery form, for example, it is preferable to mix the additive at the time of mixing the premix and the powdery substance.

According to the method for producing a resin mixture of the present invention, a uniform resin mixture having a small variation can be produced stably, so that the obtained resin mixture is directly put into a molding machine, or Then, the mixture is melted and kneaded into an extruder, extruded into a strand, and once formed into a resin composition of a granular material such as a pellet, the granular material is charged into a molding machine, and melt-kneaded and molded. The resin molded product can be made uniform with little variation.

[0032]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited to the following examples unless it exceeds the gist.

Example 1 80% by weight of ε-caprolactam as a granular resin
And 1,6-hexanediamine and adipic acid 20% by weight
85.1 parts by weight of a polyamide resin (6/66 nylon, relative viscosity 4.5) pellets which is a copolymer with
Polyamide-based resin (6I / 6T nylon, a copolymer of 50.0 mol% of 1,6-hexanediamine, 35.7 mol% of isophthalic acid and 14.3 mol% of terephthalic acid)
Relative viscosity 2.1) 6.4 parts by weight of pellets together with 0.25 part by weight of Nn-butylbenzenesulfonamide ("BM-4" manufactured by Daihachi Chemical Co., Ltd.) as an antistatic agent
The mixture was charged into a 0-liter cylindrical rotating container type mixer, and was premixed at a rotation speed of 32 times / minute with a total rotation amount of 480 times (15 minutes) to obtain a premix.

Then, 8.5 parts by weight of caprolactam (20-mesh passing material) as a powder was charged into a rotary container-type mixer with the obtained pre-mixture kept therein, and the rotation speed was 32 times / min. Mixing was performed at a total rotation of 480 times (15 minutes). The volume occupied by the mixture at this time was 40% by volume.
Met.

200 g of each of the resin mixture in the mixer was sampled from the center of the upper layer, the center of the middle layer, the left side of the middle layer, the right side of the middle layer, and the center of the lower layer, 200 g each, and the antistatic agent and caprolactam were washed with chloroform. After dropping and drying, the latter polyamide resin (6I /
6T nylon) pellets are separated and weighed,
The ratio to the total weight of the mixture was calculated and the results are shown in Table 1.

COMPARATIVE EXAMPLE 1 A mixture to be mixed was put into a 150-liter cylindrical rotary container type mixer at a time, and the total rotation amount was 4 at a rotation speed of 32 revolutions / minute.
80 times (15 minutes) (Comparative Example 1a) and 960 times (3
Except for mixing for 0 minutes (Comparative Example 1b), a resin mixture was prepared in the same manner as in Example 1, and the obtained resin mixture was subjected to polyamide resin (6I / 6T) in the same manner as in Example 1. The weight ratio of the nylon) pellets to the total weight of the mixture was calculated, and the results are shown in Table 1.

Example 2 As a mixer for premixing and mixing of the premix and the powdery material, a 1000-liter double-conical rotary container type mixer was used, and the rotation speed at that time was 26 times. /
Except that the total number of rotations was 600 times (23 minutes), a resin mixture was produced in the same manner as in Example 1, and the upper, middle, upper left, and upper right portions of the resin mixture in the mixer were mixed. , The middle part of the middle layer and the center part of the lower layer were sampled, the weight ratio to the total weight of the mixture of the polyamide resin (6I / 6T nylon) pellets was calculated in the same manner as in Example 1, and further, washing was performed. The amount of caprolactam in chloroform thus obtained was quantified by gas chromatography, and its ratio to the total weight of the mixture was calculated. The results are shown in Table 1, respectively.

Comparative Example 2 A mixture to be mixed was put into a 1000-liter double-conical frusto-conical rotary container type mixer at one time, and mixed at a rotation speed of 32 times / minute and a total rotation of 1500 times (60 minutes). Other than that, a resin mixture was produced in the same manner as in Example 2, and the obtained resin mixture was subjected to the same method as in Example 2 to obtain a weight ratio based on the total weight of the polyamide resin (6I / 6T nylon) pellets mixture, And the weight ratio to the total weight of the mixture of caprolactam was calculated, and the results are shown in Table 1.

[0039]

[Table 1]

[0040]

According to the present invention, it is possible to stably produce a uniform resin mixture having a small variation, and to extend a resin composition or a resin molded product obtained by melt-kneading the mixture. It is possible to provide a method for producing a resin mixture, which has a small variation and can be uniform.

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) C08K 5/103 C08K 5/103 5/435 5/435 13/04 13/04 C08L 67/00 C08L 67/00 69 / 00 69/00 77/00 77/00 101/16 101/00 // B29K 67:00 69:00 77:00 F term (reference) 4F070 AA47 AA50 AA54 AC36 AC43 AC50 AE01 AE02 AE03 AE04 AE05 FA01 FA17 FC02 4F201 AA24 AA28 AA29 AB09 AC04 AR09 AR15 BA01 BC01 BC12 BC37 BK12 4J002 AA00W AA00X CF00W CF00X CG00W CG00X CL00W CL00X DE136 DE146 DE236 DJ016 DJ036 DJ046 EC047 EF056 EH037 EP016 EU206 EV236 FA08W FA08X FD016 FD016 FD016FD

Claims (7)

[Claims] 1. A method for producing a mixture of two or more kinds of resin particles and one or more kinds of powders, wherein the two or more kinds of resin particles are preliminarily mixed by a rotary container type mixer and mixed with the premix. None, and then mixing the premix with one or more powders. 2. The method for producing a resin mixture according to claim 1, wherein the premixing of two or more kinds of resin particles is performed in the presence of an antistatic agent. 3. The amount of the antistatic agent in the premix is 0.01 to 10% by weight based on the total weight of the premix.
The method for producing a resin mixture according to the above. 4. The premixing of two or more kinds of resin granules is carried out at a rotation speed of a rotary container type mixer of 15 to 45 times / minute and a total rotation amount of 250 to 1000 times. A method for producing a resin mixture according to any one of the above. 5. The method for producing a resin mixture according to claim 1, wherein the mixing of the preliminary mixture and one or more kinds of powders is performed by a rotary container type mixer. 6. The mixing of the premix and one or more powders at a rotation speed of a rotary container type mixer of 15 to 45 times / min.
The method for producing a resin mixture according to claim 5, wherein the total rotation amount is 250 to 1000 times. 7. The resin according to claim 1, wherein the two or more kinds of granular resin are any resin selected from the group consisting of a polyamide resin, a polycarbonate resin, and a polyester resin. A method for producing a resin mixture.