Resin composition, hot melt molded product, and molding method

Abstract

The present invention addresses the problem of providing a resin composition containing a cellulose resin, the resin composition being provided with excellent hot-melt moldability and being capable of retaining, in an obtained hot-melt molded article, good physical properties of the cellulose resin. Further, the present invention addresses the problem of providing: a hot-melt molded article in which good physical properties of a cellulose resin are retained; and a method for molding the same. This resin composition is for hot-melt molding, contains a crystalline cellulose resin as a main component, and contains an additive satisfying formula (1).　Formula (1): T2≤T1×0.93, wherein T2 represents the melting point (°C) of a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin; and T1 represents the melting point (°C) of the crystalline cellulose resin.

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a hot-melt molded article, and a molding method. More specifically, the present invention relates to a resin composition containing a cellulose resin, which has excellent hot-melt moldability and is capable of retaining the good physical properties of the cellulose resin in the resulting hot-melt molded article, and to a molding method thereof. [Background technology]

[0002] Cellulose resins have been used for a long time and are expected to be biomass resins because of the abundance of biological resources available as raw materials. However, cellulose resins generally have high crystallinity, which causes their pyrolysis temperature and melting point to be close to each other. Furthermore, their low melt fluidity makes them poor in thermoformability, making them difficult to use for modern mass-produced objects using manufacturing methods such as injection molding.

[0003] For example, triacetyl cellulose (generally with a degree of substitution of about 2.9), a type of cellulose ester that is excellent in optical properties and heat resistance among cellulose resins, is highly crystalline and has a melting point of around 300°C, which is close to the decomposition temperature of the cellulose skeleton. Therefore, when used in thermoforming, discoloration of the resin and a decrease in molecular weight due to partial thermal decomposition were observed, making it essentially unusable as a thermoplastic resin.

[0004] Therefore, a thermoplastic grade has been commercialized by hydrolyzing triacetyl cellulose to a degree of substitution of about 2.5, thereby reducing the crystallinity, and further using a large amount of plasticizer. However, the large number of hydroxyl groups causes problems of hygroscopicity and expansion and contraction due to changes in humidity, and the addition of plasticizers also causes problems such as a decrease in the excellent physical properties of cellulose resins, such as mechanical strength.

[0005] For example, Patent Document 1 describes a method in which a resin composition containing a specific compound having a fluorene skeleton as a plasticizer and a specific amount of a stabilizer is used for cellulose ester, and the melt-kneading temperature is lowered to 240 to 290°C to pelletize the resin composition, followed by injection molding. However, it cannot be said that the method described in Patent Document 1 can sufficiently lower the temperature during molding of the resin composition, and further improvements are required in terms of moldability and the physical properties of the resulting molded product. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2015-86254 Summary of the Invention [Problem to be solved by the invention]

[0007] The present invention has been made in view of the above problems and circumstances, and aims to provide a resin composition containing a cellulose resin that has excellent hot-melt moldability and is capable of retaining the good physical properties of the cellulose resin in the resulting hot-melt molded article. It is also an object of the present invention to provide a hot-melt molded article that retains the good physical properties of the cellulose resin, and a molding method therefor. [Means for solving the problem]

[0008] In the course of investigating the causes of the above problems in order to solve the above problems, the present inventors discovered that by using an additive, in a mixture obtained by adding 10 parts by mass of additive to 90 parts by mass of crystalline cellulose resin, together with crystalline cellulose resin, whose melting point T2 is 0.93 times or less the melting point T1 of the crystalline cellulose resin, a resin composition can be obtained that has excellent hot-melt moldability and is able to retain the good physical properties of the cellulose resin in the resulting hot-melt molded product, and thus arrived at the present invention. That is, the above-mentioned problems of the present invention are solved by the following means.

[0009] 1. A resin composition for hot melt molding containing a crystalline cellulose resin as a main component, Contains an additive that satisfies the following formula (1): The additive is selected from the group consisting of the following compounds RAa-1 and RAa- 9 prongs is either RB-3, The resin composition, wherein the crystalline cellulose resin is a crystalline cellulose ester resin, and the degree of substitution of hydrogen atoms for hydroxy groups in the crystalline cellulose ester resin is 2.7 or more, and the degree of substitution of acetyl groups is 2.7 or more. Formula (1) T2≦T1×0.93 In formula (1), T2 represents the melting point [°C] of a mixture in which 10 parts by mass of the additive is added to 90 parts by mass of the crystalline cellulose resin, and T1 represents the melting point [°C] of the crystalline cellulose resin alone. [ka]

[0013] 2 Item 1, where the difference between T1 and T2 is 25°C or more to The resin composition described above.

[0014] 3 The additive satisfies the following (i), (ii), or (iii) in the following formula (2): or No. 2 The resin composition according to item 1. (i) Vu / V1<1.0 and χ<3 (ii) 1.0≦Vu / V1<1.5 and χ<6 (iii) 1.5≦Vu / V1 and χ<8 Equation (2) 1 / Tm-1 / Tm 0 =(R / △Hu)×(Vu / V1)×(ν1-χν1 2 ) In formula (2), the symbols have the following meanings. Tm: melting point (absolute temperature) of a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin Tm0 : Melting point (absolute temperature) of the crystalline cellulose resin alone R: gas constant △Hu: Heat of fusion per mole of the repeating unit forming the crystalline cellulose resin V1: Molar volume of the additive Vu: Molar volume of the repeating unit forming the crystalline cellulose resin ν1: Volume fraction of the additive in a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin χ: a parameter indicating the interaction between the crystalline cellulose resin and the additive

[0020] 4 .Items 1 to 5 3 A hot melt molded article of the resin composition according to any one of claims 1 to 5.

[0021] 5 .Items 1 to 5 3 A molding method for hot melt molding the resin composition according to any one of claims 1 to 5, The molding method is one in which the hot melt molding is carried out under conditions that satisfy the following formula (3): Formula (3) T3≦T1×0.75+20 In the formula (3), T3 represents the maximum temperature [° C.] of the resin composition during hot melt molding.

[0022] 6 Injection molding, extrusion molding, or fused deposition modeling 5 Item 2. The molding method according to item 1. [Effects of the Invention]

[0023] The above-mentioned means of the present invention can provide a resin composition containing a cellulose resin, which has excellent hot-melt moldability and can maintain the good physical properties of the cellulose resin in the resulting hot-melt molded article. It can also provide a hot-melt molded article that maintains the good physical properties of the cellulose resin, and a molding method therefor. The mechanism of manifestation or action of the effects of the present invention is speculated as follows.

[0024] As described above, in order to improve the hot melt moldability of crystalline cellulose resins, it is necessary to lower the melting point of the crystalline cellulose resin below its decomposition temperature and to increase the difference between the melting points. Decomposition reactions of cellulose derivatives include elimination of side chains due to heating, cleavage of glycosidic bonds, ring-opening of pyranose rings, which are the structural units of cellulose, and elimination reactions. These reactions are largely dependent on the structure of the polymer material, and it is difficult to achieve a high decomposition temperature by improving these factors themselves.

[0025] In addition, a method for lowering the melting point of crystalline cellulose resin is known, in which the melting point is lowered by adjusting the substituents that replace the hydrogen atoms of the three hydroxyl groups present per β-glucose residue, which is a structural unit of cellulose, and the degree of substitution during molecular design of the crystalline cellulose resin. However, it is difficult to find a method for lowering the melting point to a desired range while maintaining productivity, physical properties, etc.

[0026] On the other hand, a method is known in which additives such as plasticizers are added to crystalline cellulose resins to lower the melting point of the mixture of crystalline cellulose resins and the additives, thereby improving the hot melt moldability. As such additives, phthalate esters, trimellitate esters, glycerin, aliphatic esters of dicarboxylic acids, phosphate esters, etc. have been put to practical use, and a compound having a fluorene skeleton, as disclosed in Patent Document 1, is also known.

[0027] As a result of extensive research into additives to be used with crystalline cellulose resin, the inventors have discovered that by using an additive that satisfies the above formula (1), a composition containing crystalline cellulose resin and the additive has a melting point that is sufficiently lower than the decomposition temperature of the crystalline cellulose resin and has excellent hot-melt moldability.

[0028] Conventionally, plasticizers used for cellulose resins consist of a strongly polar moiety, such as an ester group, and a relatively large non-polar moiety consisting of a long-chain alkyl group, as described above. The polar moiety of the plasticizer orients to the polar moiety of the cellulose resin, and the large non-polar moiety widens the spacing between the polymer chains, facilitating molecular motion of the polymer chains and lowering the glass transition temperature (Tg) and melting point.

[0029] In a composition containing a polymer compound and a plasticizer, Tg decreases in accordance with the ratio of the volume fractions of the polymer compound (Tg1) and the plasticizer (Tg2, where Tg1 > Tg2), whereas the decrease in melting point is small, with the melting point decrease limit defined in the present invention (see definition below) being approximately 0.95. It is presumed that additives satisfying formula (1) according to the present invention operate using a mechanism completely different from conventional mechanisms. Furthermore, due to the operation of this previously unknown mechanism, the degree of decrease in the quality of hot-melt molded products, which normally decreases with a decrease in melting point, is reduced, and the resulting hot-melt molded products can maintain the good physical properties of the crystalline cellulose resin. DETAILED DESCRIPTION OF THE INVENTION

[0030] The resin composition of the present invention is a resin composition for hot melt molding containing a crystalline cellulose resin as a main component, and is characterized by containing an additive satisfying the above formula (1). This characteristic is a technical characteristic common to each of the following embodiments.

[0031] In an embodiment of the resin composition of the present invention, the crystalline cellulose resin is preferably a crystalline cellulose ester resin, from the viewpoint of ease of processing and the mechanical properties of the resulting hot melt molded article.

[0032] When the crystalline cellulose resin is a crystalline cellulose ester resin, the degree of substitution of hydrogen atoms of hydroxy groups in the crystalline cellulose ester resin is preferably 2.7 or more, and the degree of substitution of acetyl groups in the crystalline cellulose ester resin is preferably 2.5 or more.More preferably, the degree of substitution of acetyl groups in the crystalline cellulose ester resin is 2.7 or more.

[0033] The "degree of substitution of hydrogen atoms of hydroxy groups" in a crystalline cellulose ester resin refers to the number of esterified hydroxy groups, three of which exist per structural unit of cellulose, in other words, the number of hydroxy groups whose hydrogen atoms have been substituted with acyl groups, averaged over the entire resin, and is expressed as 0 to 3. The "degree of substitution of hydrogen atoms of hydroxy groups" in a crystalline cellulose ester resin is also referred to as the "degree of acyl group substitution." When two or more types of acyl groups substitute for hydrogen atoms in a crystalline cellulose ester resin, the sum of the degrees of substitution for each acyl group is the degree of acyl group substitution.

[0034] In crystalline cellulose ester resin, when the substitution degree of acetyl group among acyl group is high, melting point is closer to the decomposition temperature of cellulose skeleton, and there is a need to improve hot melt moldability.Therefore, when the substitution degree of hydrogen atom of hydroxyl group, that is, acyl group substitution degree is 2.7 or more, and acetyl group substitution degree is 2.5 or more, the effect of the present invention by using the additive that satisfies above-mentioned formula (1) is more significant, and when acetyl group substitution degree is 2.7 or more, the effect of the present invention is particularly significant.

[0035] In an embodiment of the resin composition of the present invention, the difference between T1 and T2 is preferably 25° C. or more, from the viewpoint of exhibiting the effects of the present invention.

[0036] In an embodiment of the resin composition of the present invention, the additive preferably satisfies the following (i), (ii) or (iii) in the above formula (2): (i) Vu / V1<1.0 and χ<3 (ii) 1.0≦Vu / V1<1.5 and χ<6 (iii) 1.5≦Vu / V1 and χ<8

[0037] The above formula (2) is a formula described in a literature (P.J. Flory, PRINCIPALES OF POLYMER CHEMISTRY (1953)) based on a statistical thermodynamic interpretation by Flory, Haggins, et al. In this literature, formula (2) is described as a formula showing the relationship between polymer materials and additives, not limited to the relationship between crystalline cellulose resins and additives.

[0038] In equation (2), χ is a parameter that indicates the interaction between the crystalline polymer and the additive. In principle, the above equation is derived on the assumption that there is no difference between the interactions between the repeating units that form the crystalline polymer, between the additives, and between the repeating units that form the crystalline polymer and the additives. Therefore, the ideal state is χ = 0, but in reality, there are interactions between crystalline polymers, between additives, and between the crystalline polymer and the additives, so it often shows a value other than 0.

[0039] In the crystalline cellulose resin of the present invention, χ>0 indicates a direction in which the interaction between the crystalline cellulose resin and the additive is weaker than the interactions between other crystalline cellulose resins and between the additives, making mixing difficult, compared to the ideal state. χ<0 indicates a direction in which the interaction between the crystalline cellulose resin and the additive is stronger than the interactions between other crystalline cellulose resins and between the additives, making mixing of the additive into the crystalline cellulose resin easier, compared to the ideal state.

[0040] In an embodiment of the resin composition of the present invention, the smaller the value of χ, the greater the effect of the present invention. Specifically, χ is preferably less than 8, more preferably 3 or less, and even more preferably 0 or less.

[0041] Furthermore, the required range of χ varies depending on the value of Vu / V1 in formula (2). In formula (2), Vu / V1 represents the ratio of the molar volume (Vu) of the repeating units forming the crystalline cellulose resin to the molar volume (V1) of the additive. When Vu / V1 is 1.0 or more and less than 1.5, χ is preferably less than 6 (condition (ii) above); when Vu / V1 is less than 1.0, χ is preferably less than 3 (condition (i) above); and when Vu / V1 is 1.5 or more, χ is preferably less than 8 (condition (iii) above). From the opposite perspective, the larger Vu / V1 is, the wider the range of usable χ becomes, which is preferable in terms of broadening the scope of additive selection.

[0042] By satisfying condition (i), condition (ii), or condition (iii), additives tend to be more easily mixed into the crystalline cellulose resin, and it is expected that compositions containing these will have better hot-melt moldability.

[0043] In an embodiment of the resin composition of the present invention, the additive preferably includes a compound having a structure represented by the general formula RAa, RAb, or RB, in terms of the effect of the present invention.

[0044] The hot-melt molded article of the present invention is characterized by being produced by hot-melt molding using the resin composition of the present invention.

[0045] The molding method of the present invention is a molding method for hot melt molding a resin composition, characterized in that the hot melt molding is carried out under conditions that satisfy the above formula (3). The molding method of the present invention is preferably an injection molding method, an extrusion molding method, or a fused deposition modeling method.

[0046] The present invention, its constituent elements, and embodiments and modes for carrying out the present invention will be described in detail below. In this application, the symbol "to" is used to mean that the numerical values ​​before and after it are included as lower and upper limits. In this specification, "contained as a main component" and "mainly composed of" mean that the main component accounts for 50% by mass or more of the whole.

[0047] [Resin composition] The resin composition of the present invention is a resin composition for hot melt molding containing a crystalline cellulose resin as a main component, and is characterized by containing an additive satisfying the following formula (1): Hereinafter, the additive satisfying formula (1) will also be referred to as additive (A). Formula (1) T2≦T1×0.93 In formula (1), T2 represents the melting point [°C] of a mixture in which 10 parts by mass of the additive is added to 90 parts by mass of the crystalline cellulose resin, and T1 represents the melting point [°C] of the crystalline cellulose resin alone.

[0048] In this specification, the term "crystalline cellulose resin" is used as a general term for resins made of cellulose derivatives having a melting point. A resin having a melting point means that it exhibits a clear endothermic peak rather than a stepwise endothermic change in differential scanning calorimetry (DSC). Specifically, a clear endothermic peak means a peak in which the half-width of the endothermic peak upon melting is within 30°C when measured in DSC, for example, at a heating rate of 10°C / min.

[0049] The melting point T1 [°C] of the crystalline cellulose resin alone can be measured using a DSC device. Specifically, T1 is the peak temperature [°C] of the endothermic peak obtained by DSC.

[0050] The melting point T2 [°C] of a mixture (hereinafter also referred to as mixture (S)) in which 10 parts by mass of additive (A) is added to 90 parts by mass of crystalline cellulose resin can be measured using a DSC device in the same manner as above, using mixture (S) instead of crystalline cellulose resin alone.

[0051] Specifically, the mixture (S) is prepared as follows: 90 parts by mass of crystalline cellulose resin is dissolved in 1,900 parts by mass of a mixed solvent of methylene chloride and methanol (mixing ratio (mass ratio): methylene chloride:methanol = 9:1), to which 10 parts by mass of additive (A) is added and mixed, and the solvent is then removed using an evaporator, and the resulting solid is dried at 110°C, giving mixture (S).

[0052] The resin composition of the present invention has excellent hot-melt moldability because the relationship between the melting point T1 of the crystalline cellulose resin alone and the melting point T2 of the mixture (S) satisfies formula (1), and the resulting hot-melt molded product can retain the good physical properties of the cellulose resin.

[0053] The resin composition of the present invention may optionally contain other components in addition to the crystalline cellulose resin and additive (A) as long as the effects of the present invention are not impaired. Examples of other components include resins other than the crystalline cellulose resin, additives other than additive (A), etc. Each component contained in the resin composition of the present invention will be described below.

[0054] (crystalline cellulose resin) The resin composition of the present invention contains a crystalline cellulose resin as a main component. The content of the crystalline cellulose resin in the resin composition of the present invention is 50% by mass or more, preferably 60% by mass or more, and more preferably 70% by mass or more. The components contained in the resin composition of the present invention are broadly classified into resins and additives. The resin may be composed of only crystalline cellulose resin, or may be composed of a combination of crystalline cellulose resin and other resins. The other resins will be described later. The proportion of the crystalline cellulose resin relative to the total amount of resins is, for example, preferably 55 to 100% by mass, more preferably 70 to 100% by mass, and more preferably 100% by mass, while maintaining the content of the crystalline cellulose resin as a main component in the resin composition.

[0055] Specific examples of the crystalline cellulose resin include crystalline cellulose ester resin, crystalline cellulose ether resin, etc. From the viewpoint of ease of processing and the mechanical properties of the resulting hot melt molded product, crystalline cellulose ester resin is preferably used.

[0056] The crystalline cellulose ester resin preferably has an acyl group substitution degree of 2.7 or more from the viewpoint of being less susceptible to the influence of moisture, and more preferably has an acyl group substitution degree in the range of 2.8 to 3.0.

[0057] The acyl group in the crystalline cellulose ester resin is not particularly limited as long as it is an acyl group represented by RC(=O)- (R is a monovalent hydrocarbon group). As the acyl group, for example, an acyl group in which R is an aliphatic hydrocarbon group having 1 to 5 carbon atoms is preferred, and an acetyl group in which R is a methyl group, a propionyl group in which R is an ethyl group, or a butyryl group in which R is a propyl group is more preferred, with an acetyl group being particularly preferred. Furthermore, the acetyl group substitution degree in the crystalline cellulose ester resin is preferably 2.5 or more, more preferably 2.7 or more.

[0058] The acyl group of the crystalline cellulose ester resin may be one type or two or more types. The acyl group of the crystalline cellulose ester resin is preferably one type, and the one type is preferably an acetyl group from the viewpoint of cost and physical properties. The substitution degree of the acyl group of the crystalline cellulose ester resin can be measured in accordance with ASTM-D817-96.

[0059] The weight average molecular weight (Mw) of the crystalline cellulose ester resin is 10 × 10 3 ~1000×10 3 It is preferable that the range is 50×10 3 ~500×10 3 The number average molecular weight (Mn) of the crystalline cellulose ester resin is more preferably within the range of 10 × 10 3 ~1000×10 3 It is preferable that the range is 10 × 10 3 ~500×10 3 It is more preferable that the ratio (Mw / Mn) of the weight average molecular weight (Mw) to the number average molecular weight (Mn) of the crystalline cellulose ester resin is in the range of 1-5.

[0060] If the molecular weight characteristics of the crystalline cellulose ester resin are within the above range, it is preferable in terms of the hot melt moldability of the resin composition and the physical properties of the hot melt molded product obtained.

[0061] The weight average molecular weight (Mw) and number average molecular weight (Mn) of the crystalline cellulose ester resin can be measured, for example, by gel permeation chromatography (GPC) under the following conditions.

[0062] Solvent: methylene chloride Column: Shodex K806, K805, K803G (Showa Denko K.K., three columns connected together) Column temperature: 25℃ Sample concentration: 0.1% by mass Detector: RI Model 504 (GL Sciences) Pump: L6000 (Hitachi, Ltd.) Flow rate: 1.0ml / min Calibration curve: A calibration curve was used using 13 samples of standard polystyrene STK standard polystyrene (manufactured by Tosoh Corporation) with Mw = 1,000,000 to 500. The 13 samples were used at approximately equal intervals.

[0063] Crystalline cellulose ester resins can be produced by known methods. Generally, raw cellulose is mixed with a specific organic acid (acetic acid, propionic acid, butyric acid, etc.), an acid anhydride (acetic anhydride, propionic anhydride, butyric anhydride, etc.), and a catalyst (sulfuric acid, etc.) to esterify the cellulose, and the reaction proceeds until a cellulose triester is produced. In the triester, the three hydroxy groups of the glucose unit are substituted with an acyl acid of the organic acid. Using two types of organic acids simultaneously allows the production of mixed ester cellulose acylates, such as cellulose acetate propionate and cellulose acetate butyrate.

[0064] Next, the cellulose triester is hydrolyzed as necessary to synthesize a crystalline cellulose ester resin having a desired degree of acyl group substitution, which is then subjected to steps such as filtration, precipitation, washing with water, dehydration, and drying to obtain the crystalline cellulose ester resin.

[0065] In the above, the raw material cellulose may be wood pulp or cotton linter, and the wood pulp may be either softwood or hardwood, but softwood is preferred. Cotton linter is preferred from the viewpoint of releasability during molding. Crystalline cellulose ester resins made from these may be used alone or in appropriate mixtures.

[0066] For example, the ratio of cotton linter-derived cellulose acylate:wood pulp (coniferous)-derived cellulose acylate:wood pulp (broadleaf)-derived cellulose acylate can be 100:0:0, 90:10:0, 85:15:0, 50:50:0, 20:80:0, 10:90:0, 0:100:0, 0:0:100, 80:10:10, 85:0:15, or 40:30:30.

[0067] Furthermore, the crystalline cellulose ester resin may be, for example, a cellulose acylate produced by the above-mentioned method, in which the acyl group substitution degree and the acetyl group substitution degree are adjusted by mixing two or more types of cellulose acylates having different acyl group substitution degrees.

[0068] The crystalline cellulose ester resin according to the present invention preferably has a pH in the range of 6 to 7 and an electrical conductivity in the range of 1 to 100 μS / cm when 1 g of the resin is added to 20 ml of pure water (electrical conductivity of 0.1 μS / cm or less, pH 6.8) and stirred at 25°C for 1 hour under a nitrogen atmosphere.

[0069] Specifically, the crystalline cellulose ester resin according to the present invention can be synthesized with reference to the methods described in JP-A-10-45804 and JP-A-2017-170881.

[0070] The crystalline cellulose ester resin of the present invention may be a commercially available product, such as LT-35 (manufactured by Daicel Corporation), L-30 (manufactured by Daicel Corporation), CA3205 (manufactured by Eastman Corporation), or CAP482-20 (manufactured by Eastman Corporation).

[0071] (Other resins) The resin composition of the present invention may contain, as necessary, other resins in addition to the crystalline cellulose resin, as long as the effects of the present invention are not impaired.

[0072] Specific examples of other resins include amorphous cellulose resins, polyolefin resins, polystyrene resins, polyamide resins, polyimide resins, polyester resins, acrylic resins, polyurethane resins, vinyl chloride resins, vinyl acetate resins, epoxy resins, phenolic resins, melamine resins, polycarbonate resins, polyacetal resins, polyphenylene ether resins, polyphenylene sulfide resins, polysulfone resins, styrene-acrylonitrile copolymers (AS resins), styrene-(meth)acrylic acid copolymers, styrene-methyl methacrylate copolymers, acrylonitrile-butadiene-styrene copolymers (ABS resins), and methyl methacrylate-butadiene-styrene copolymers (MBS resins).

[0073] Other resins that may be used include biomass-derived polylactic acid (PLA), polybutyl succinate (PBS), polybutyl succinate adipate (PBSA), and polyhydroxyalkanoic acid (PHA, for example, polyhydroxybutyric acid (PHB)). In particular, from the viewpoint of utilizing biomass resources, these biomass-derived resins are preferably used.

[0074] The content of the other resin in the resin composition is preferably 45% by mass or less, more preferably 30% by mass or less, based on the total amount of the crystalline cellulose resin and the other resin, and particularly preferably zero.

[0075] (Additive (A)) The additive (A) is a compound that satisfies the above formula (1) in relation to the crystalline cellulose resin contained in the resin composition. Specifically, the additive (A) is a compound that can adjust the melting point T2 [°C] of a mixture (hereinafter also referred to as mixture (X)) obtained by mixing the crystalline cellulose resin and the additive (A) in a mass ratio of 9:1 to 0.93 times or less the melting point T1 [°C] of the crystalline cellulose resin alone.

[0076] Equation (1) is expressed as T2≦T1×0.93. Transforming this gives T2 / T1≦0.93. Hereinafter, the value (T2 / T1) obtained by dividing the melting point T2 of the mixture (S) by the melting point T1 of the crystalline cellulose resin alone is referred to as the melting point depression degree of the additive (A) relative to the crystalline cellulose resin. The melting point depression degree of the additive (A) relative to the crystalline cellulose resin is preferably 0.91 or less, more preferably 0.89 or less. Although it depends on the composition of the resin composition, the lower the melting point depression degree of the additive (A) relative to the crystalline cellulose resin, the more excellent the hot-melt moldability of the resulting resin composition.

[0077] The difference between the melting point T1 of the crystalline cellulose resin alone and the melting point T2 of the mixture (S) is preferably 25° C. or more. That is, it is preferable that the following formula (4) is satisfied. Formula (4) T1-T2≧25[℃] In formula (4), T1-T2 refers to the melting point difference between the crystalline cellulose resin and the mixture (S). The melting point difference between the crystalline cellulose resin and the mixture (S) is more preferably 30°C or more. Although it depends on the composition of the resin composition, the greater the melting point difference between the crystalline cellulose resin and the mixture (S) of the additive (A), the better the hot melt moldability of the resin composition obtained.

[0078] The additive (A) preferably satisfies the following (i), (ii) or (iii) in the following formula (2): (i) Vu / V1<1.0 and χ<3 (ii) 1.0≦Vu / V1<1.5 and χ<6 (iii) 1.5≦Vu / V1 and χ<8 Equation (2) 1 / Tm-1 / Tm 0 =(R / △Hu)×(Vu / V1)×(ν1-χν1 2 )

[0079] In formula (2), the symbols have the following meanings. Tm: melting point (absolute temperature [K]) of a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin Tm 0: Melting point of the crystalline cellulose resin alone (absolute temperature [K]) R: gas constant △Hu: Heat of fusion per mole of the repeating unit forming the crystalline cellulose resin [J / mol] V1: Molar volume of the additive Vu: Molar volume of the repeating unit forming the crystalline cellulose resin ν1: Volume fraction of the additive in a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin χ: a parameter indicating the interaction between the crystalline cellulose resin and the additive

[0080] Tm[K] and Tm in formula (2) 0 [K] are the absolute temperatures of T2 [°C] and T1 [°C] in formula (1), respectively. 0 [K] can be calculated from T2 [°C] and T1 [°C] measured using a DSC device as described above. In this specification, although units may not be added to these symbols, Tm and Tm 0 The unit of is [K], and the unit of T2 and T1 is [°C].

[0081] R is the gas constant, and is 8.31 [J / K·mol]. △Hu is the heat of fusion [J / mol] per mole of repeating units that make up the crystalline cellulose resin, and was measured using a DSC device. That is, △Hu is the heat of fusion per mole of crystalline cellulose resin (J / mol), calculated from the area of ​​the endothermic peak during melting of the crystalline cellulose resin alone measured using a DSC device, divided by the number of units that make up the crystalline cellulose resin. V1, Vu, and ν1 can each be calculated from literature values, etc.

[0082] The values ​​other than χ in formula (2) are determined as described above and inserted into formula (2) to determine χ. χ is a parameter indicating the interaction between the crystalline cellulose resin and the additive (A), and as explained above, in the embodiment of the resin composition of the present invention, the smaller the value, the better; specifically, χ is preferably less than 8, more preferably 3 or less, and even more preferably 0 or less.

[0083] Note that χ can be appropriately adjusted according to the value of Vu / V1 in the formula (2), dividing the case into (i), (ii), and (iii).

[0084] When Vu / V1 is less than 1.0, χ is preferably less than 3 due to condition (i). When Vu / V1 is 1.0 or more and less than 1.5, χ is preferably less than 6 due to condition (ii). When Vu / V1 is 1.5 or more, χ is preferably less than 8 due to condition (iii).

[0085] In formula (2), when the left side of the formula is the same, the larger Vu / V1 is, the larger χ tends to be. The left side of formula (2) becomes larger as the degree of melting point depression decreases in relation to formula (1). When additive (A) is used, the left side of formula (2) can be increased, and the value of χ can be reduced even if Vu / V1 is relatively large.

[0086] The structure of additive (A) is not limited as long as it is a compound that satisfies formula (1). However, common structures of additive (A) that can satisfy formula (1) include structures having multiple amino groups, hydroxy groups, and carboxy groups in the molecule, and structures having a nitrogen-containing heterocycle. These structures include ammonium groups in which amino groups are quaternized, onium groups, ester groups in which multiple amino groups, hydroxy groups, and carboxy groups are condensed in the molecule, amide groups, acid anhydrides, imide groups, and the like. In addition, additive (A) preferably has an aromatic ring in the molecule.

[0087] As additive (A), for example, an amino alcohol having a structure represented by the following general formula RAa or RAb, or a nitrogen-containing aromatic heterocyclic five-membered compound having a structure represented by the following general formula RB is preferred. Hereinafter, a compound having a structure represented by general formula RAa may be abbreviated as "compound RAa". Compounds having structures represented by other general formulas may also be abbreviated in the same manner. Compound RAa and compound RAb will be collectively referred to as "compound RA".

[0088] [ka]

[0089] In the formula, R 1 , R 2 R each independently represents a divalent linking group. 3 R each independently represents a hydrogen atom or a substituent. 4 represents a hydrogen atom, a substituted or unsubstituted alkyl group, or an aryl group. - represents an organic or inorganic monovalent anion.

[0090] [ka]

[0091] In the formula, A represents a nitrogen-containing aromatic heterocyclic five-membered ring. 5 is an atom or group bonded to a ring-constituting atom of A, and represents a hydrogen atom or a substituent. n represents the total number of atoms or groups bonded to a ring-constituting atom of A. When n is 2 or more, multiple R 5 may be the same or different, and may be bonded to each other to form an aromatic ring structure. 5 may have an onium salt structure, in which case the counter anion is an organic or inorganic anion.

[0092] Furthermore, a compound that is not included in the compounds RA and RB but has a structure that is preferable as the additive (A) is referred to as "compound RC." Compound RC includes compounds that have a structure that has multiple amino groups, hydroxy groups, and carboxy groups in the molecule and does not have the structure of compounds RA and RB. Specific examples of compound RC include compounds R-1 to R-11 whose structures are represented by the following R-1 to R-11, respectively.

[0093] [ka]

[0094] The additive (A) may be used alone or in combination of two or more. When two or more types are used in combination, the mixture of the two or more types satisfies formula (1). Among these, the compound RA and the compound RB are preferred as the additive (A). The compound RA and the compound RB will be explained in more detail below.

[0095] <Compound RA> Among the compounds RA, the compound RAa is a primary, secondary or tertiary amino alcohol, and the compound RAb is a quaternary amino alcohol.

[0096] In the general formula RAa and the general formula RAb, R 1 , R 2 R each independently represents a divalent linking group. 1 and R 2 Specific examples of the groups include, independently of one another, substituted or unsubstituted divalent hydrocarbon groups having 1 to 10 carbon atoms, which may have a nitrogen atom between carbon atoms, and which are linear or branched and may have a cyclic structure. Examples of the substituent in the divalent hydrocarbon group include a hydroxy group and an amino group, with a hydroxy group being preferred.

[0097] R 1 and R 2may each have a branched chain, and the branched chains may be bonded to each other to form a nitrogen atom-containing heterocycle having 4 to 7 members. In this case, the heterocycle is preferably a 5-membered ring.

[0098] R 1 and R 2 For example, -C n H 2n - (n is an integer of 1 to 10, preferably 2 or 3. n H 2n may be branched.) -C m H 2m -N(-C s H 2s -OH)-C t H 2t -(m, s, and t are each independently an integer of 1 to 10, and m is preferably 2 or 3. s and t are preferably 1 to 3. C m H 2m , C s H 2s , C t H 2t may be branched.

[0099] In the general formula RAa and the general formula RAb, R 3 represents a hydrogen atom or a substituent. 3 Examples of R include substituted or unsubstituted monovalent hydrocarbon groups having 1 to 10 carbon atoms, which are linear or branched and may have a cyclic structure. 3 Examples of the alkyl group include an aryl group having 4 to 10 carbon atoms, which may have a substituent, a heteroaromatic ring group, and an alkyl group having 1 to 10 carbon atoms, which may have a substituent. Examples of the substituent on the aryl group, heteroaromatic ring group, or alkyl group include a halogen atom such as F, Cl, or Br, a hydroxy group, an aryl group bonded via an amide bond, an ester bond, or an ether bond, an aralkyl group, an alkyl group, an alkenyl group, or an alkynyl group. Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group.

[0100] In the general formula RAb, R 4represents a hydrogen atom, a substituted or unsubstituted alkyl group, or an aryl group. 4 A specific example of this is R 3 The specific example can be the same as X. - represents an organic or inorganic monovalent anion. Examples of monovalent anions include F - , Cl - , Br - Halogen ions such as CH3COO - , CF3COO - and other organic anions.

[0101] Specific examples of compound RAa include compounds RAa-1 to RAa-9 whose structures are respectively represented in the following RAa-1 to RAa-9. Specific examples of compound RAb include compounds RAb-10 to RAb-11 whose structures are respectively represented in the following RAb-10 to RAb-11.

[0102] [ka]

[0103] [ka]

[0104] <Compound RB> Compound RB is a nitrogen-containing aromatic heterocyclic five-membered compound having a structure represented by the general formula RB. In the formula, A represents a nitrogen-containing aromatic heterocyclic five-membered ring. Ring A can have 1 to 3 nitrogen atoms, preferably 1 or 2. Ring A may have another heteroatom other than the nitrogen atom. Examples of the other heteroatom include an oxygen atom and a sulfur atom.

[0105] Examples of ring A include a pyrrole ring, an imidazole ring, a pyrazole ring, a triazole ring, a thiazole ring, an oxazole ring, an oxadiazole ring, a thiadiazole ring, a dioxazole ring, a dithiazole ring, and a tetrazole ring.

[0106] R 5is an atom or group bonded to a ring-constituting atom of A, and represents a hydrogen atom or a substituent. n represents the total number of atoms or groups bonded to a ring-constituting atom of A. When n is 2 or more, multiple R 5 may be the same or different, and may be bonded to each other to form an aromatic ring structure.

[0107] R in the case of a substituent 5 Examples of R include substituted or unsubstituted monovalent hydrocarbon groups having 1 to 10 carbon atoms, which are linear or branched and may have a cyclic structure. 5 Examples of the alkyl group include an aryl group having 4 to 10 carbon atoms, which may have a substituent, a heteroaromatic ring group, and an alkyl group having 1 to 10 carbon atoms, which may have a substituent. Examples of the substituent on the aryl group, heteroaromatic ring group, or alkyl group include a halogen atom such as F, Cl, or Br, an aryl group bonded via an amide bond, an ester bond, or an ether bond, an aralkyl group, an alkyl group, an alkenyl group, or an alkynyl group. Examples of the aryl group include a phenyl group, a tolyl group, a xylyl group, and a naphthyl group.

[0108] Multiple R 5 When two adjacent R 5 are bonded to each other. The aromatic ring formed in this manner is referred to as ring B. Ring B preferably has 5 to 7 members and may have 1 to 3 heteroatoms. The heteroatoms in ring B may be in positions shared with ring A or may not be in positions shared by ring B. The heteroatoms in ring B are preferably selected from a nitrogen atom, an oxygen atom, and a sulfur atom.

[0109] Ring B may have a substituent, and examples of the substituent include, as described above, a halogen atom such as F, Cl, or Br, an aryl group, an aralkyl group, an alkyl group, an alkenyl group, or an alkynyl group bonded via an amide bond, an ester bond, or an ether bond, and the like.

[0110] R attached to heteroatom 5may have an onium salt structure, in which case the counter anion is an organic or inorganic anion. When the heteroatom is a nitrogen atom, the counter anion is a monovalent anion. Examples of the monovalent anion include F - , Cl - , Br - Halogen ions such as CH3COO - , CF3COO - and other organic anions.

[0111] Specific examples of the compound RB include compounds RB-1 to RB-9 whose structures are represented by the following RB-1 to RB-9, respectively.

[0112] [ka]

[0113] The additive (A) is appropriately selected depending on the type of crystalline cellulose resin so as to satisfy formula (1), preferably formula (4), or so as to satisfy conditions (i), (ii), or (iii).

[0114] A preferred combination of the crystalline cellulose resin and the additive (A) in the resin composition of the present invention is, for example, a combination in which the crystalline cellulose resin is a crystalline cellulose ester resin having an acetyl substitution degree of 2.7 or more, and the additive (A) is a compound R-1 to R-11, a compound RA, or a compound RB. In this combination, the additive (A) is preferably a compound RA or a compound RB, and is preferably a compound RAa-1, a compound RAa-9, or a compound RAa-1. , conversion Compound RB-3 and compound RB-6 are more preferred.

[0115] The resin composition of the present invention containing additive (A) is a resin composition for hot melt molding, and is used by heating the resin composition to a temperature close to its melting point during molding. Therefore, it is preferable that additive (A) has a property such that it does not substantially evaporate or sublimate when heated during molding. Specifically, the boiling point of additive (A) is preferably 200°C or higher, more preferably 230°C or higher.

[0116] The content of additive (A) in the resin composition of the present invention is preferably 5 to 30 parts by mass, and more preferably 10 to 25 parts by mass, per 100 parts by mass of the total amount of the crystalline cellulose resin and additive (A). When the content of additive (A) is within the above range, the hot melt moldability of the resin composition is improved, and the good physical properties of the cellulose resin can be sufficiently maintained in the obtained hot melt molded product.

[0117] (Other additives) The resin composition of the present invention may contain, as necessary, additives other than the additive (A) as additives to the resin, within the range that does not impair the effects of the present invention.

[0118] Other additives include plasticizers, heat stabilizers, antioxidants, release agents, UV absorbers, dyes and pigments, flame retardants, antistatic agents, anti-fogging agents, lubricants / anti-blocking agents, flow improvers, dispersants, deodorizers, and antibacterial agents.

[0119] As the plasticizer, known plasticizers can be used as long as the effects of the present invention are not impaired. Specific examples of plasticizers include polyester compounds, polyhydric alcohol ester compounds, polycarboxylic acid ester compounds (including phthalic acid ester compounds), glycolate compounds, and ester compounds (including fatty acid ester compounds and phosphate ester compounds). These may be used alone or in combination of two or more.

[0120] The diol constituting the polyester compound is an aromatic diol, an aliphatic diol, or an alicyclic diol, preferably an aliphatic diol, and more preferably a diol having 1 to 4 carbon atoms. The diol may be one type or a mixture of two or more types.

[0121] In particular, the polyester compound preferably contains a repeating unit obtained by reacting at least a dicarboxylic acid containing an aromatic dicarboxylic acid with a diol having 1 to 4 carbon atoms, and more preferably contains a repeating unit obtained by reacting a dicarboxylic acid containing an aromatic dicarboxylic acid and an aliphatic dicarboxylic acid with a diol having 1 to 4 carbon atoms.

[0122] Both ends of the molecule of the polyester compound may or may not be blocked, but from the viewpoint of reducing the moisture permeability of the hot melt molded article, it is preferable that they are blocked.

[0123] The polyester compound is preferably a compound having a structure represented by the following general formula (I) or (II): In the following formula, n is an integer of 1 or more.

[0124] General formula (I) B-(GA) n -GB General formula (II) C-(AG) n -AC A in general formulas (I) and (II) represents a divalent group derived from an alkylene dicarboxylic acid having 3 to 20 carbon atoms (preferably 4 to 12), a divalent group derived from an alkenylene dicarboxylic acid having 4 to 20 carbon atoms (preferably 4 to 12), or a divalent group derived from an aryl dicarboxylic acid having 8 to 20 carbon atoms (preferably 8 to 12).

[0125] Examples of the divalent group for A derived from an alkylene dicarboxylic acid having 3 to 20 carbon atoms include divalent groups derived from 1,2-ethanedicarboxylic acid (succinic acid), 1,3-propanedicarboxylic acid (glutaric acid), 1,4-butanedicarboxylic acid (adipic acid), 1,5-pentanedicarboxylic acid (pimelic acid), 1,8-octanedicarboxylic acid (sebacic acid), etc. Examples of the divalent group for A derived from an alkenylene dicarboxylic acid having 4 to 20 carbon atoms include divalent groups derived from maleic acid, fumaric acid, etc. Examples of the divalent group for A derived from an aryl dicarboxylic acid having 8 to 20 carbon atoms include divalent groups derived from benzene dicarboxylic acids such as 1,2-benzenedicarboxylic acid (phthalic acid), 1,3-benzenedicarboxylic acid, and 1,4-benzenedicarboxylic acid, and naphthalene dicarboxylic acids such as 1,5-naphthalene dicarboxylic acid, etc.

[0126] A may be one type or a combination of two or more types. Among these, A is preferably a combination of an alkylene dicarboxylic acid having 4 to 12 carbon atoms and an aryl dicarboxylic acid having 8 to 12 carbon atoms.

[0127] G in general formulas (I) and (II) represents a divalent group derived from an alkylene glycol having 2 to 20 carbon atoms (preferably 2 to 12), a divalent group derived from an aryl glycol having 6 to 20 carbon atoms (preferably 6 to 12), or a divalent group derived from an oxyalkylene glycol having 4 to 20 carbon atoms (preferably 4 to 12).

[0128] Examples of the divalent group in G derived from an alkylene glycol having 2 to 20 carbon atoms include ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,2-butanediol, 1,3-butanediol, 1,2-propanediol, 2-methyl-1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 2,2-dimethyl-1,3-propanediol (neopentyl glycol), 2,2-diethyl-1,3-propanediol, and the like. divalent groups derived from 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolpentane), 2-n-butyl-2-ethyl-1,3-propanediol (3,3-dimethylolheptane), 3-methyl-1,5-pentanediol, 1,6-hexanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 1,10-decanediol, and 1,12-octadecanediol, etc.

[0129] Examples of the divalent group in G derived from an aryl glycol having 6 to 20 carbon atoms include divalent groups derived from 1,2-dihydroxybenzene (catechol), 1,3-dihydroxybenzene (resorcinol), 1,4-dihydroxybenzene (hydroquinone), etc. Examples of the divalent group in G derived from an oxyalkylene glycol having 4 to 20 carbon atoms include divalent groups derived from diethylene glycol, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, etc.

[0130] G may be one type or a combination of two or more types, and among these, G is preferably an alkylene glycol having 2 to 12 carbon atoms.

[0131] B in general formula (I) is a monovalent group derived from an aromatic ring-containing monocarboxylic acid or an aliphatic monocarboxylic acid.

[0132] The aromatic ring-containing monocarboxylic acid in the monovalent group derived from an aromatic ring-containing monocarboxylic acid is a carboxylic acid containing an aromatic ring in the molecule, and includes not only those in which the aromatic ring is directly bonded to a carboxy group, but also those in which the aromatic ring is bonded to a carboxy group via an alkylene group, etc. Examples of the monovalent group derived from an aromatic ring-containing monocarboxylic acid include monovalent groups derived from benzoic acid, para-tert-butylbenzoic acid, orthotoluic acid, meta-toluic acid, para-toluic acid, dimethylbenzoic acid, ethylbenzoic acid, normal propylbenzoic acid, aminobenzoic acid, acetoxybenzoic acid, phenylacetic acid, 3-phenylpropionic acid, etc.

[0133] Examples of monovalent groups derived from aliphatic monocarboxylic acids include monovalent groups derived from acetic acid, propionic acid, butanoic acid, caprylic acid, caproic acid, decanoic acid, dodecanoic acid, stearic acid, oleic acid, etc. Among these, monovalent groups derived from alkyl monocarboxylic acids having an alkyl moiety with 1 to 3 carbon atoms are preferred, and an acetyl group (a monovalent group derived from acetic acid) is more preferred.

[0134] C in general formula (II) is a monovalent group derived from an aromatic ring-containing monoalcohol or an aliphatic monoalcohol.

[0135] The aromatic ring-containing monoalcohol is an alcohol containing an aromatic ring in the molecule, and includes not only those in which the aromatic ring is directly bonded to an OH group, but also those in which the aromatic ring is bonded to an OH group via an alkylene group, etc. Examples of monovalent groups derived from aromatic ring-containing monoalcohols include monovalent groups derived from benzyl alcohol, 3-phenylpropanol, etc.

[0136] Examples of monovalent groups derived from aliphatic monoalcohols include monovalent groups derived from methanol, ethanol, propanol, isopropanol, butanol, isobutanol, pentanol, isopentanol, hexanol, isohexanol, cyclohexyl alcohol, octanol, isooctanol, 2-ethylhexyl alcohol, nonyl alcohol, isononyl alcohol, tert-nonyl alcohol, decanol, dodecanol, dodecahexanol, dodecaoctanol, allyl alcohol, oleyl alcohol, etc. Among these, monovalent groups derived from alcohols having 1 to 3 carbon atoms such as methanol, ethanol, propanol, and isopropanol are preferred.

[0137] The weight-average molecular weight of the polyester compound is preferably in the range of 500 to 3000, more preferably in the range of 600 to 2000. If the weight-average molecular weight is within the above range, the polyester compound is likely to satisfy the resistance to exudation from the hot-melt molded article according to the present invention. The weight-average molecular weight can be measured by the gel permeation chromatography (GPC) described above.

[0138] The polyhydric alcohol ester compound is an ester compound (alcohol ester) of a dihydric or higher aliphatic polyhydric alcohol with a monocarboxylic acid, and is preferably a di- to 20-hydric aliphatic polyhydric alcohol ester. The polyhydric alcohol ester compound preferably has an aromatic ring or a cycloalkyl ring in the molecule.

[0139] Preferred examples of the aliphatic polyhydric alcohol include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, 1,2-propanediol, 1,3-propanediol, dipropylene glycol, tripropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, dibutylene glycol, 1,2,4-butanetriol, 1,5-pentanediol, 1,6-hexanediol, hexanetriol, trimethylolpropane, pentaerythritol, trimethylolethane, xylitol, etc. Among these, triethylene glycol, tetraethylene glycol, dipropylene glycol, tripropylene glycol, sorbitol, trimethylolpropane, xylitol, etc. are preferred.

[0140] The monocarboxylic acid is not particularly limited and may be an aliphatic monocarboxylic acid, an alicyclic monocarboxylic acid, an aromatic monocarboxylic acid, or the like. To increase the moisture permeability and reduce the volatility of the hot-melt molded product, an alicyclic monocarboxylic acid or an aromatic monocarboxylic acid is preferred. The monocarboxylic acid may be one type or a mixture of two or more types. Furthermore, all of the OH groups contained in the aliphatic polyhydric alcohol may be esterified, or some of the OH groups may remain as they are.

[0141] The aliphatic monocarboxylic acid is preferably a fatty acid having a straight or branched chain and having 1 to 32 carbon atoms. The number of carbon atoms in the aliphatic monocarboxylic acid is more preferably 1 to 20, and even more preferably 1 to 10. Examples of the aliphatic monocarboxylic acid include saturated fatty acids such as acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, 2-ethylhexanoic acid, undecylic acid, lauric acid, tridecylic acid, myristic acid, pentadecylic acid, palmitic acid, heptadecylic acid, stearic acid, nonadecanoic acid, arachidic acid, behenic acid, lignoceric acid, cerotic acid, heptacosanoic acid, montanic acid, melissic acid, and lacteric acid; and unsaturated fatty acids such as undecylenic acid, oleic acid, sorbic acid, linoleic acid, linolenic acid, and arachidonic acid. Among these, acetic acid or a mixture of acetic acid and other monocarboxylic acids is preferred in order to enhance compatibility with cellulose acetate.

[0142] Examples of the alicyclic monocarboxylic acid include cyclopentanecarboxylic acid, cyclohexanecarboxylic acid, cyclooctanecarboxylic acid, and the like.

[0143] Examples of aromatic monocarboxylic acids include benzoic acid; benzoic acid having one to three alkyl or alkoxy groups (e.g., methoxy or ethoxy groups) introduced into the benzene ring (e.g., toluic acid); and aromatic monocarboxylic acids having two or more benzene rings (e.g., biphenylcarboxylic acid, naphthalenecarboxylic acid, tetralincarboxylic acid), with benzoic acid being preferred.

[0144] Specific examples of polyhydric alcohol ester compounds include the compounds described in paragraphs

[0058] to

[0061] of JP-A No. 2006-113239.

[0145] The polycarboxylic acid ester compound is an ester compound of a divalent or higher polycarboxylic acid, preferably a divalent to 20-valent polycarboxylic acid, and an alcohol compound. The polycarboxylic acid is preferably a divalent to 20-valent aliphatic polycarboxylic acid, a trivalent to 20-valent aromatic polycarboxylic acid, or a trivalent to 20-valent alicyclic polycarboxylic acid.

[0146] Examples of polycarboxylic acids include trivalent or higher aromatic polycarboxylic acids or derivatives thereof, such as trimellitic acid, trimesic acid, and pyromellitic acid; aliphatic polycarboxylic acids, such as succinic acid, adipic acid, azelaic acid, sebacic acid, oxalic acid, fumaric acid, maleic acid, and tetrahydrophthalic acid; and oxypolycarboxylic acids, such as tartaric acid, tartronic acid, malic acid, and citric acid. In order to suppress volatilization from hot-melt molded articles, oxypolycarboxylic acids are preferred.

[0147] Examples of alcohol compounds include linear or branched aliphatic saturated alcohol compounds, linear or branched aliphatic unsaturated alcohol compounds, alicyclic alcohol compounds, and aromatic alcohol compounds. The number of carbon atoms in the aliphatic saturated alcohol compounds or aliphatic unsaturated alcohol compounds is preferably 1 to 32, more preferably 1 to 20, and even more preferably 1 to 10. Examples of alicyclic alcohol compounds include cyclopentanol and cyclohexanol. Examples of aromatic alcohol compounds include benzyl alcohol and cinnamyl alcohol.

[0148] The molecular weight of the polycarboxylic acid ester compound is not particularly limited, but is preferably in the range of 300 to 1000, and more preferably in the range of 350 to 750. From the viewpoint of suppressing bleed-out, the molecular weight of the polycarboxylic acid ester plasticizer is preferably larger; from the viewpoint of moisture permeability and compatibility with cellulose acetate, the molecular weight is preferably smaller.

[0149] Examples of the polycarboxylic acid ester compound include triethyl citrate, tributyl citrate, acetyl triethyl citrate (ATEC), acetyl tributyl citrate (ATBC), benzoyl tributyl citrate, acetyl triphenyl citrate, acetyl tribenzyl citrate, dibutyl tartrate, diacetyl dibutyl tartrate, tributyl trimellitate, tetrabutyl pyromellitate, and the like.

[0150] The polycarboxylic acid ester compound may be a phthalic acid ester compound. Examples of the phthalic acid ester compound include diethyl phthalate, dimethoxyethyl phthalate, dimethyl phthalate, dioctyl phthalate, dibutyl phthalate, di-2-ethylhexyl phthalate, dioctyl phthalate, dicyclohexyl phthalate, and dicyclohexyl terephthalate.

[0151] Examples of glycolate compounds include alkylphthalyl alkyl glycolates. Examples of alkylphthalyl alkyl glycolates include methylphthalyl methyl glycolate, ethylphthalyl ethyl glycolate, propylphthalyl propyl glycolate, butylphthalyl butyl glycolate, octylphthalyl octyl glycolate, methylphthalyl ethyl glycolate, ethylphthalyl methyl glycolate, ethylphthalyl propyl glycolate, methylphthalyl butyl glycolate, ethylphthalyl butyl glycolate, butylphthalyl methyl glycolate, butylphthalyl ethyl glycolate, propylphthalyl butyl glycolate, butylphthalyl propyl glycolate, methylphthalyl octyl glycolate, ethylphthalyl octyl glycolate, octylphthalyl methyl glycolate, octylphthalyl ethyl glycolate, etc., and preferably ethylphthalyl ethyl glycolate.

[0152] The ester compounds include fatty acid ester compounds, citrate ester compounds, phosphate ester compounds, and the like.

[0153] Examples of fatty acid ester compounds include butyl oleate, methylacetyl ricinoleate, and dibutyl sebacate. Examples of citrate ester compounds include acetyltrimethyl citrate, acetyltriethyl citrate, and acetyltributyl citrate. Examples of phosphoric acid ester compounds include triphenyl phosphate, tricresyl phosphate, cresyl diphenyl phosphate, octyl diphenyl phosphate, biphenyl diphenyl phosphate, trioctyl phosphate, and tributyl phosphate, with triphenyl phosphate being preferred.

[0154] Of these, polyester compounds, polyhydric alcohol ester compounds and glycolate compounds are preferred, with polyester compounds and polyhydric alcohol ester compounds being particularly preferred.

[0155] The content of the plasticizer is preferably in the range of 1 to 30 parts by mass, more preferably 1.5 to 15 parts by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention. When the content of the plasticizer is within the above range, the effect of imparting plasticity can be exhibited, and the resistance to exudation of the plasticizer from the hot-melt molded product is also excellent.

[0156] Examples of the heat stabilizer include phosphorus-based compounds. Any conventionally known phosphorus-based compound can be used. Specific examples include phosphorus oxoacids such as phosphoric acid, phosphonic acid, phosphorous acid, phosphinic acid, and polyphosphoric acid; metal acid pyrophosphates such as sodium acid pyrophosphate, potassium acid pyrophosphate, and calcium acid pyrophosphate; phosphates of Group 1 or Group 2 metals such as potassium phosphate, sodium phosphate, cesium phosphate, and zinc phosphate; organic phosphate compounds, organic phosphite compounds, and organic phosphonite compounds.

[0157] The content of the above phosphorus-based compound is usually 0.001 to 1 part by mass, preferably 0.01 to 0.7 parts by mass, and more preferably 0.03 to 0.5 parts by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0158] Antioxidants are also called deterioration inhibitors. Hindered phenol compounds are preferably used as antioxidants, such as 2,6-di-t-butyl-p-cresol, pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], triethylene glycol-bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate], 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 2,4-bis-(n-octylthio)-6-(4-hydroxy-3,5-di-t-butylazone), and the like. Examples of suitable hydroxybenzoates include N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxybenzyl)benzene, N,N'-hexamethylenebis(3,5-di-t-butyl-4-hydroxybenzyl)benzene, and tris-(3,5-di-t-butyl-4-hydroxybenzyl)isocyanurate.

[0159] Particularly preferred are 2,6-di-t-butyl-p-cresol, pentaerythrityl tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], and triethylene glycol bis[3-(3-t-butyl-5-methyl-4-hydroxyphenyl)propionate]. Hydrazine-based metal deactivators such as N,N'-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionyl]hydrazine and phosphorus-based processing stabilizers such as tris(2,4-di-t-butylphenyl)phosphite may also be used in combination.

[0160] The release agent may be at least one compound selected from the group consisting of aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds having a number average molecular weight of 200 to 15,000, and polysiloxane-based silicone oils. The content of the release agent is usually 0.001 to 2 parts by mass, and preferably 0.01 to 1 part by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0161] Examples of ultraviolet absorbers include inorganic ones such as cerium oxide and zinc oxide, as well as organic ones such as benzotriazole compounds, benzophenone compounds, and triazine compounds. Among these, organic ones are preferred. In particular, at least one selected from the group consisting of benzotriazole compounds, 2-(4,6-diphenyl-1,3,5-triazin-2-yl)-5-[(hexyl)oxy]phenol, 2-[4,6-bis(2,4-dimethylphenyl)-1,3,5-triazin-2-yl]-5-(octyloxy)phenol, 2,2'-(1,4-phenylene)bis[4H-3,1-benzoxazin-4-one], and [(4-methoxyphenyl)-methylene]-propanediol dimethyl ester is preferred. The content of the ultraviolet absorber is usually 0.01 to 3 parts by mass, and preferably 0.1 to 1 part by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0162] Examples of dyes and pigments include inorganic pigments, organic pigments, and organic dyes. Examples of inorganic pigments include sulfide pigments such as carbon black, cadmium red, and cadmium yellow; silicate pigments such as ultramarine; oxide pigments such as titanium oxide, zinc white, red iron oxide, chromium oxide, iron black, titanium yellow, zinc-iron brown, titanium-cobalt green, cobalt green, cobalt blue, copper-chromium black, and copper-iron black; chromate pigments such as yellow lead and molybdate orange; and ferrocyanide pigments such as iron blue. The content of the dyes and pigments is usually 5 parts by mass or less, preferably 3 parts by mass or less, and more preferably 2 parts by mass or less, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0163] Examples of flame retardants include halogenated flame retardants such as halogenated bisphenol A polycarbonate, brominated bisphenol epoxy resin, brominated bisphenol phenoxy resin, and brominated polystyrene, phosphate flame retardants, organometallic salt flame retardants such as dipotassium diphenylsulfone-3,3'-disulfonate, potassium diphenylsulfone-3-sulfonate, and potassium perfluorobutanesulfonate, and polyorganosiloxane flame retardants, with phosphate flame retardants being preferred. The content of the flame retardant is usually 1 to 30 parts by mass, preferably 3 to 25 parts by mass, and more preferably 5 to 20 parts by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0164] As the various additives, commercially available products such as Adeka Cizer O-130P (manufactured by ADEKA Corporation, epoxy plasticizer) and Irgaphos 168 (manufactured by BASF Japan Ltd., tris(2,4-di-t-butylphenyl)phosphite) may be used.

[0165] Various fillers can also be blended. The fillers to be blended are not particularly limited as long as they are those generally used in resin compositions for hot melt molding, and powdery, fibrous, granular, and plate-like inorganic fillers, as well as resin-based fillers and natural fillers, can be preferably used. Inorganic or organic fine particles are preferably used as fillers.

[0166] Examples of inorganic fine particles include fine particles of silicon dioxide (silica), titanium dioxide, aluminum oxide, zirconium oxide, calcium carbonate, talc, clay, calcined kaolin, calcined calcium silicate, hydrated calcium silicate, aluminum silicate, magnesium silicate, calcium phosphate, etc. Among these, silicon dioxide fine particles and zirconium oxide fine particles are preferred, and silicon dioxide fine particles are more preferred.

[0167] Examples of silicon dioxide fine particles include Aerosil R972, R972V, R974, R812, 200, 200V, 300, R202, OX50, TT600, and NAX50 (all manufactured by Nippon Aerosil Co., Ltd.), and Seahoster KE-P10, KE-P30, KE-P50, and KE-P100 (all manufactured by Nippon Shokubai Co., Ltd.). Of these, Aerosil R972V, NAX50, and Seahoster KE-P30 are particularly preferred because they reduce the coefficient of friction.

[0168] The primary particle diameter of the fine particles is preferably in the range of 5 to 50 nm, and more preferably in the range of 7 to 20 nm. A larger primary particle diameter is more effective in improving the slipperiness of the resulting molded product, but is more likely to reduce transparency. Therefore, the fine particles may be contained as secondary aggregates with a particle diameter in the range of 0.05 to 0.3 μm. The size of the primary particles or secondary aggregates of the fine particles can be determined by observing the primary particles or secondary aggregates with a transmission electron microscope at a magnification of 500,000 to 2,000,000 times and calculating the average particle diameter of 100 primary particles or secondary aggregates.

[0169] The content of the fine particles is preferably in the range of 0.05 to 1.0 part by mass, more preferably in the range of 0.1 to 0.8 part by mass, per 100 parts by mass of the total of the resin and additive (A) in the resin composition of the present invention.

[0170] (Production of Resin Composition) The resin composition of the present invention is obtained by appropriately mixing the essential components, crystalline cellulose resin and additive (A), and the optional components described above. In order to fully exhibit the effects of the present invention when used in hot melt molding, it is preferable that the components are sufficiently mixed at the molecular level.

[0171] Specifically, a method for producing a resin composition includes dissolving the crystalline cellulose resin, additive (A), and optional components in a solvent capable of dissolving at least the crystalline cellulose resin and additive (A) (dispersing any optional components that do not dissolve), thoroughly mixing the components, and then removing the solvent to obtain a mixture (resin composition).

[0172] Alternatively, a solution of additive (A) and other optional additives dissolved or dispersed in a solvent, or additive (A) and other optional additives, when used with a crystalline cellulose resin or other optional resins, may be added to the crystalline cellulose resin and other resins (hereinafter simply referred to as "resin components") and mixed in a mixer. Examples of mixers that can be used include a Banbury mixer, a roll, and a Brabender mixer.

[0173] In the above method, additive (A) and other additives may be added to the resin component in several portions to prevent the concentrations of additive (A) and other additives from becoming locally high. Furthermore, a method in which the temperature of the mixer is kept warm or kinetic energy during mixing is utilized to mix at a temperature of 50°C to 200°C is preferred.

[0174] In order to prevent the decomposition of the crystalline cellulose resin, the temperature during mixing is preferably set to T1×0.75+20°C or less, as in the case of hot melt molding, which will be described later. If the mixing temperature rises due to the kinetic energy of mixing, etc., it is preferable to prevent the temperature of the mixture from exceeding T1×0.75+20°C by cooling with cooling water, air cooling, etc., or by stopping the mixing operation and allowing it to cool naturally.

[0175] Furthermore, during the above mixing, additive (A) and other additives may be thoroughly mixed together and added to the resin component as an additive mixture, or it is also preferable to add additive (A) to the crystalline cellulose resin to mix it as a composition with a lowered melting point (thermal melt processing temperature).

[0176] The resin composition of the present invention may be obtained, for example, by mixing the above-mentioned components using a mixer by the above-mentioned method, followed by further melt-kneading. As the mixer, the same mixers as those described above can be used, and for melt-kneading, a single-screw kneading extruder, a twin-screw kneading extruder, a kneader, etc. can be used. Also, a method can be used in which the components are not mixed in advance, or only some of the components are mixed in advance and fed into an extruder by a feeder to be melt-kneaded.

[0177] The temperature during melt-kneading (melt-kneading temperature) is appropriately set depending on the type and composition of the crystalline cellulose resin and additive (A). The melt-kneading temperature does not need to be higher than the melting temperature of the resin composition, and from the viewpoint of suppressing decomposition of the crystalline cellulose resin, it is preferable to carry out the melt-kneading at a temperature equal to or lower than T1 × 0.75 + 20°C, as described above.

[0178] In the melt-kneading, the kneaded material is extruded in the form of strands, and then the strand-like kneaded material can be processed into pellets, flakes, or other shapes.

[0179] The resin composition of the present invention can be in various forms, such as powder, granules, tablets, pellets, flakes, fibers (filaments), and liquid.

[0180] [Hot melt molding products] The hot melt molded article of the present invention can be obtained by hot melt molding the resin composition of the present invention. As the hot melt molding method, any known hot melt molding method using a general thermoplastic resin composition can be applied without any particular limitation. As a preferred molding method, the molding method of the present invention described below can be mentioned.

[0181] When producing a hot melt molded product, for example, a resin composition can be hot melted in various molding machines and molded into a desired shape. Molding methods commonly used for thermoplastic resins can be used. Examples include general injection molding, ultra-high speed injection molding, injection compression molding, two-color molding, gas-assisted hollow molding, molding using an insulated mold, molding using a rapidly heated mold, foam molding (including supercritical fluid), insert molding, IMC (in-mold coating) molding, extrusion molding, compression molding, blow molding, calendar molding, inflation molding, sheet molding, thermoforming, rotational molding, lamination molding, press molding, fused deposition modeling, and the like.

[0182] Furthermore, a molding method using a hot runner system can also be adopted. Sheet- or film-shaped molded products obtained by extrusion molding, calendar molding, or the like can also be subjected to secondary molding such as vacuum molding or pressure molding.

[0183] Suitable molding methods for the resin composition of the present invention include injection molding, extrusion molding, and fused deposition modeling. Extrusion molding includes melt spinning, in which a molten resin composition is extruded into fibers using a melt extrusion spinning machine. Fused deposition modeling, also known as FDM (Fused Deposition Modeling), is a molding method that uses a 3D printer based on three-dimensional printing (also called "3D printing") technology.

[0184] The hot-melt molded article of the present invention can be obtained by hot-melt molding the resin composition of the present invention at a temperature significantly lower than the decomposition temperature of the crystalline cellulose resin, thereby suppressing the decomposition of the crystalline cellulose resin during hot-melt molding, and maintaining the inherent properties of the crystalline cellulose resin used as a molding raw material, such as transparency, rigidity, and toughness.

[0185] The degree to which the decomposition of the crystalline cellulose resin during hot melt molding is suppressed can be determined, for example, by the weight average molecular weight (Mwafter ) of the weight average molecular weight (Mw before ) to the ratio (Mw after / Mw before The weight average molecular weight (Mw) of the crystalline cellulose resin in the hot melt molded product can be used as an index for evaluation. after ) can be determined by scraping off a part of the sample and subjecting it to GPC in the same manner as above. after / Mw before is preferably about 0.6 or more, more preferably 0.7 or more, and even more preferably 0.8 or more.

[0186] The rigidity of the hot-melt molded article of the present invention can be evaluated using as an index the flexural modulus measured in a bending test carried out in accordance with JIS K 7171. The test specimen used in the bending test is a scaled test specimen prepared in accordance with JIS K 7139. According to the hot-melt molded article of the present invention, the flexural modulus is preferably 3.0 GPa or more, more preferably 3.5 GPa or more, and even more preferably 4.5 GPa or more.

[0187] The toughness of the hot melt molded article of the present invention can be evaluated using as an index the Charpy impact strength measured in a Charpy impact test carried out in accordance with JIS K7110. As a test piece to be used in the Charpy impact test, a strip test piece prepared in accordance with JIS K7139 is notched using a notching machine (for example, a Toyo Seiki notching machine). According to the hot melt molded article of the present invention, the Charpy impact strength is 10 kJ / m or less. 2 It is preferable that the concentration is 12 kJ / m or more. 2 More preferably, it is 14 kJ / m or more. 2 More preferably, it is equal to or greater than this.

[0188] When the hot melt molded article of the present invention is a fiber, its physical properties can be evaluated by the strength and elongation at break measured in a tensile test carried out in accordance with JIS L 1015. The strength at break of the fiber is preferably 0.5 cN / dtex or more, more preferably 0.9 cN / dtex or more, and even more preferably 1.3 cN / dtex or more. The elongation at break of the fiber is preferably 30% or more, more preferably 40% or more, and even more preferably 45% or more.

[0189] The hot melt molded article of the present invention is useful for a variety of applications, such as electrical and electronic equipment and parts thereof, office automation equipment, information terminal equipment, machine parts, home appliances, vehicle parts, medical instruments, building materials, various containers, leisure goods and miscellaneous goods, and lighting equipment, and is particularly expected to be applicable to electrical and electronic equipment, vehicle parts, and medical instruments.

[0190] Examples of housings, covers, keyboards, buttons and switch components for electric / electronic devices, office automation equipment and information terminal devices include display devices such as personal computers, game consoles and televisions, printers, copy machines, scanners, fax machines, electronic organizers and PDAs, electronic desk calculators, electronic dictionaries, cameras, video cameras, mobile phones, drives and readers for recording media, mice, numeric keypads, CD players, MD players, portable radios and portable audio players.

[0191] Examples of vehicle components include headlamps, helmet shields, etc. Examples of interior components include interior door handles, center panels, instrument panels, console boxes, luggage floor boards, display housings for car navigation systems, etc.

[0192] Medical devices include artificial limbs and prosthetic hands.

[0193] [Hot melt molding method] The molding method of the present invention is a molding method for hot melt molding the resin composition of the present invention, characterized in that the hot melt molding is carried out under conditions that satisfy the following formula (3): Formula (3) T3≦T1×0.75+20 In the formula (3), T3 represents the maximum temperature [° C.] of the resin composition during hot melt molding.

[0194] As the molding method of the present invention, the same methods as those for the above-mentioned hot melt molded product of the present invention can be applied, and among them, injection molding, extrusion molding, and fused deposition modeling are preferred.

[0195] When hot melt molding is performed, it is preferable to perform it at a temperature as low as possible below the decomposition temperature of the crystalline cellulose resin. By performing hot melt molding at a temperature of T1 x 0.75 + 20 [°C] or less, decomposition of the crystalline cellulose resin can be sufficiently suppressed. T3 is preferably a temperature of T1 x 0.75 + 10 [°C] or less.

[0196] The resin composition of the present invention has a melting point sufficiently lower than that of the crystalline cellulose resin contained therein, and therefore can be hot-melt molded at a low temperature of not more than T1 × 0.75 + 20° C. Furthermore, when hot-melt molding is performed by a molding method that applies strong shearing forces, such as injection molding, extrusion molding, or fused deposition modeling, T3 can be further reduced due to the influence of shearing forces, etc.

[0197] As described above, the maximum temperature when the resin composition of the present invention is processed into various forms such as pellets can be set to a low temperature of not more than T1 x 0.75 + 20°C. That is, in the present invention, the crystalline cellulose resin as a resin component can be processed into a hot-melt molded product without being exposed to temperatures higher than T1 x 0.75 + 20°C in all steps from the production of the resin composition to hot-melt molding. This suppresses decomposition of the crystalline cellulose resin, allowing for the production of hot-melt molded products with good physical properties.

[0198] T3 is the maximum temperature of the resin composition during hot melt molding, and although it depends on the method and apparatus used for hot melt molding, in most cases it is the temperature of the resin composition immediately after it has come out of a die or nozzle, etc. For example, in the case of injection molding, T3 is the temperature of the resin composition immediately after it has come out of the die through which the resin composition is injected from the kneader into the mold, and in the case of extrusion molding and fused deposition modeling in 3D printing, it indicates the temperature of the resin composition immediately after it has been extruded from the die or nozzle, respectively.

[0199] The molding method of the present invention can be any general melt molding method without any particular limitation, except that the resin composition of the present invention is used to perform melt molding under conditions that satisfy formula (3). Fused deposition modeling and melt spinning will be described below, but the molding method is not limited to these.

[0200] (Fused Deposition Modeling) Fused deposition modeling can be performed using, for example, a 3D printer. In addition to fused deposition modeling, 3D printers can also perform fusion molding using inkjet methods, stereolithography, plaster powder lamination methods, and selective laser sintering (SLS) methods.

[0201] A 3D printer generally has a chamber, which contains a heatable base, an extrusion head installed in a gantry structure, a heat melter, a resin composition (kneaded material) guide, a raw material supply unit such as a resin composition cartridge installation unit, etc. Some 3D printers have an integrated extrusion head and heat melter.

[0202] The extrusion head is mounted on a gantry structure, allowing it to be moved freely on the XY plane of the base. The base is a platform on which the desired 3D object and support material are constructed, and it is preferable that it be designed so that it can be heated and kept warm to ensure adhesion with the laminated material and improve the dimensional stability of the resulting resin object as the desired 3D object. Typically, at least one of the extrusion head and base is movable in the Z-axis direction, which is perpendicular to the XY plane.

[0203] The 3D printer filament is fed from a raw material supply unit, fed to an extrusion head by a pair of opposing rollers or gears, heated and melted in the extrusion head, and extruded from a tip nozzle. The temperature of the resin composition immediately after extrusion from the tip nozzle is T3, and is set to a temperature of T1 × 0.75 + 20 [°C] or less, preferably T1 × 0.75 + 10 [°C] or less.

[0204] Here, for example, signals are sent based on a CAD model, and the extrusion head moves to supply and deposit the resin composition onto the substrate. After this process is complete, the deposited layer is removed from the substrate, and the support material is peeled off or excess portions are cut off as needed to obtain the desired three-dimensional object.

[0205] Examples of means for continuously supplying a resin composition to an extrusion head include a method of feeding the resin composition, a method of feeding a powder or liquid from a tank or the like via a metering feeder, and a method of extruding pellets or granules that have been plasticized using an extruder or the like, and then feeding the extrusion. However, from the viewpoint of process simplicity and supply stability, the method of feeding the resin composition is most preferred.

[0206] (Melt spinning method) The melt spinning method according to the present invention is a method in which the resin composition of the present invention is heated and melted in a known melt extrusion spinning machine, extruded through a nozzle, spun, and optionally stretched and wound up. In this case, the temperature of the resin composition immediately after being extruded through the nozzle is the spinning temperature T3. The spinning temperature is set to a temperature equal to or lower than T1×0.75+20°C, preferably 180 to (T1×0.75+20)°C, and more preferably 190 to (T1×0.75+20)°C. A spinning temperature of 180°C or higher is preferred because it reduces the melt viscosity and improves melt spinnability. Furthermore, by setting the spinning temperature to T1×0.75+20°C or lower, thermal decomposition of the crystalline cellulose resin in the resin composition can be suppressed.

[0207] To obtain fibers with good mechanical properties, the spinning speed is preferably 300 to 3000 m / min, more preferably 300 to 2500 m / min, and even more preferably 300 to 2000 m / min.

[0208] The cross-sectional shape of the fiber as a hot melt molded product obtained by the melt spinning method according to the present invention is not particularly limited, and may be a circular cross section such as a perfect circle, or an irregular cross section such as multi-lobal, flat, elliptical, W-shaped, S-shaped, X-shaped, H-shaped, C-shaped, square-shaped, hollow, etc. Also, it may be a composite fiber such as a core-sheath composite, eccentric core-sheath composite, side-by-side composite, or mixed fiber with different finenesses. [Example]

[0209] The present invention will be specifically described below with reference to examples, but the present invention is not limited to these. In the examples, the terms "parts" and "%" are used, but unless otherwise specified, they represent "parts by mass" or "% by mass."

[0210] [Crystalline cellulose resin] Four types of crystalline cellulose ester resins shown in Table I were prepared, each substituted with an Ac group (acetyl group) or with both an Ac group and a Pr group (propionyl group). The molecular weights are weight-average molecular weights calculated as standard polystyrene standards, determined by GPC using the method described above. The degrees of Ac group substitution and Pr group substitution were determined using NMR in accordance with ASTM-D817-96, based on the integral ratio of the hydroxyl group and each substituent. The degree of acyl group substitution is the sum of the degrees of Ac group substitution and the degree of Pr group substitution.

[0211] The melting point T1 [°C] of the crystalline cellulose resin and the heat of fusion ΔHu [J / mol] per mole of the repeating unit forming the crystalline cellulose resin were determined by DSC (DSC7000X (manufactured by Hitachi High-Tech Science Corporation)).

[0212] [Table 1]

[0213] [Additives] The additives shown in Table II were prepared. The abbreviations for the additives were the same as those of the compounds. Compounds Cf1, Cf2, and Cf3 are additives outside the scope of the present invention and used for comparison, with the structures shown below. Compound R-4, Compound RAa-1, Compound RAa- 9th grade and compound RB-3 are additives corresponding to additive (A) having the above structure.

[0214] [ka]

[0215] For these additives, T2 was measured as follows using the crystalline cellulose resins shown in Table I to confirm whether they satisfied various conditions such as formula (1).

[0216] 90 parts of crystalline cellulose resin was dissolved in 1900 parts of a mixed solvent of methylene chloride and methanol (mixing ratio (mass ratio): methylene chloride:methanol = 9:1), and 10 parts of additive was mixed with the solution. The solvent was then removed using an evaporator, and the solid was then dried at 110°C to obtain a solid. The melting point (T2) of the obtained solid was determined using DSC, and the results shown in Table II were obtained.

[0217] Table II shows the melting point depression (T2 / T1), melting point difference (T1-T2), Vu / V1, and χ. If the melting point depression (T2 / T1) is 0.93 or less, the additive satisfies formula (1) and falls within the category of additive (A) of the present invention. T1-T2 is preferably 25°C or higher. The relationship between Vu / V1 and χ preferably satisfies condition (i), (ii), or (iii).

[0218] [Table 1]

[0219] [Manufacturing of injection molded products 1] The crystalline cellulose resins in Table I and the additives in Table II were combined as shown in Table III and injection molded by the following method to produce hot melt molded products 1 to 12. In Table III, the "weight average molecular weight" in the column below the crystalline cellulose resin number is the weight average molecular weight of the crystalline cellulose resin x 10 3 The same applies to Tables IV to VI.

[0220] (1) Preparation of resin composition The crystalline cellulose resin and additives were dissolved and mixed in a mixed solvent of methylene chloride and methanol (mixing ratio (mass ratio): methylene chloride:methanol = 9:1) in an amount 20 times the total mass of the crystalline cellulose resin and additives. The solvent was then removed using an evaporator, and the resulting solid was scraped off to obtain a powder (resin composition) for hot melt processing.

[0221] (2) Injection molding Each resin composition obtained above was mixed and injection molded at various temperatures using a small mixer, and the lowest temperature at which mixing and injection molding were possible was designated as the molding temperature T3 [°C] (maximum temperature during molding) in Table III. Each resin composition was injection molded at the temperature T3 to prepare JIS K7139 scaled test pieces and JIS K7139 rectangular test pieces.

[0222] (3) Evaluation The flexural modulus, Charpy impact strength, coloring, and weight average molecular weight of the resin constituting the molded article after molding were measured by the following methods. The results are shown in the lower column of Table III.

[0223] 3-1: Flexural modulus A bending test was carried out in accordance with JIS K7171 using a JIS K7139 scale test piece to determine the bending modulus.

[0224] 3-2: Charpy impact strength The JIS K7139 rectangular test pieces were notched using a Toyo Seiki notching machine, and then subjected to a Charpy impact test in accordance with JIS K7110 to determine the Charpy impact strength.

[0225] 3-3; ​​Coloring The coloring was evaluated by placing a JIS K7139 scaled test piece on a white paper, visually observing the coloring, and judging according to the following criteria. (Evaluation criteria) 〇: Almost no coloring is noticeable. △: Slight coloring, but no practical problem. ×: Discoloration is evident and there is a problem in practical use.

[0226] 3-4; Weight average molecular weight after molding A part of the JIS K7139 scale test piece was cut off, and the molecular weight was determined using GPC in the same manner as for the crystalline cellulose resin alone, and expressed as a weight average molecular weight.

[0227] [Table 2]

[0228] [Manufacturing of injection molded products 2] The crystalline cellulose resin in Table I and the additives shown in Table II were combined as shown in Table IV to prepare pellets (resin compositions) for hot melt processing by the following method, and then injection molded to produce hot melt molded products 201 to 206.

[0229] (1)Mixture 8 kg of crystalline cellulose resin 100, 50 g of stabilizer 1 (BASF's "Irgaphos 168"), and 50 g of stabilizer 2 (ADEKA's "Adeka Cizer O-130P") were mixed for 5 minutes using a Nippon Coke Corporation FM40 mixer at a jacket temperature of 40°C and 1000 rpm.

[0230] Then, while stirring at 1000 rpm, 2 kg of additive RAa-9 was added every minute in five 400 g portions. During this time, the internal temperature was maintained at 40-50°C. After the addition of additive RAa-9 was completed, stirring was continued at 1000 rpm, and the jacket temperature was increased at 10°C / min. After reaching 90°C, stirring was continued at 1000 rpm for 30 minutes. After that, while stirring at 100 rpm, the jacket temperature was increased to 20°C, and mixing was stopped when the internal temperature reached 30°C. This resulted in a powder mixture containing the above components.

[0231] (2) Preparation of pellets (resin composition) The powder obtained above was pelletized using a Laboplastomill (manufactured by Toyo Seiki Co., Ltd.) equipped with a twin-screw segment extruder and a cold cutter pelletizer, which was operated under the following conditions. Rotation speed: 100 rpm Discharge amount: 150g / min Kneading temperature: 210℃ Die temperature: 220℃

[0232] (3) Injection molding The pellets (resin composition) prepared above were dried at 80°C for 12 hours and then injection molded under the following conditions to prepare test pieces of hot melt molded product 201 having the same shape as those molded in the above-mentioned Production of Injection Molded Product 1. The injection molding temperature corresponds to the temperature of the resin composition immediately after it emerges from the die through which the resin composition is injected from the kneader into the mold, and is the maximum temperature (T3) during molding. Injection molding temperature 220℃ Mold temperature: 60℃ Injection molding pressure: 80 MPa

[0233] As with the above-mentioned hot melt molded product 201, hot melt molded products 202, 203, 204, and 206 were produced by changing some of the conditions as shown in Table IV. Note that, for the hot melt molded product 205, kneading during injection molding was not possible, and an injection molded product could not be produced.

[0234] In the production of hot melt molded products, the maximum temperature during injection molding is shown as T3 in Table IV. In the case of hot melt molded product 206, the maximum temperature during pellet (resin composition) production was higher than T3, and the maximum temperature during pellet (resin composition) production is shown in the T3 column of Table IV as the maximum temperature during processing.

[0235] (4) Evaluation The flexural modulus, Charpy impact strength, coloration, and weight-average molecular weight of the resin constituting the molded article after molding were measured using the same methods as those used to evaluate the molded article in the above-mentioned injection-molded article production 1. The results are shown in the lower column of Table IV.

[0236] [Table 4]

[0237] [Manufacturing of fused molded products by fused deposition modeling] The crystalline cellulose resin in Table I and the additives shown in Table II were combined as shown in Table V, and hot melt molded articles 301 to 305 were produced by fused deposition modeling using a 3D printer in the following manner.

[0238] (1) Preparation of filament (resin composition) A powder was prepared as a mixture of crystalline cellulose resin 100, stabilizer 1, stabilizer 2, and additive RAa-9 in the same manner as in the case of the thermal melt molded product 201. The obtained powder was kneaded and extruded in a twin-screw kneader in the same manner as in the case of the thermal melt molded product 201, and pulled to a diameter of 1.75 mm in a cold cutter unit, without using a cutter, to prepare a filament (resin composition) for 3D printer molding.

[0239] (2) Thermal melt molding using a 3D printer (fused deposition modeling) The 3D printer filament obtained above was supplied to the raw material supply section of a 3D printer, Raise3D Pro2 (manufactured by RAISE3D). The 3D printer filament was heated and melted in the extrusion head, extruded from the nozzle tip, and fused deposition modeling was performed. The nozzle temperature (corresponding to the temperature of the resin composition immediately after extrusion from the nozzle) was the maximum temperature (T3) during molding. Test pieces of fused deposition modeling 301 with the same shape as those molded in Production of Injection Molded Products 1 and 2 using the 3D printer were produced. In this case, the x-axis direction was the length direction of the test piece, the y-axis direction was the width direction, and the z-axis was the thickness direction.

[0240] (3D printer conditions) Nozzle temperature: 220℃ Bed temperature: 100℃ Layer pitch: 0.3 mm Output speed: 50mm / s

[0241] Similar to the above-mentioned thermal melt molded product 301, thermal melt molded products 302, 303, and 304 were produced by changing some of the conditions as shown in Table V. Note that the thermal melt molded product 305 could not be extruded using a 3D printer, and therefore a thermal melt molded product could not be produced.

[0242] (3) Evaluation The flexural modulus, Charpy impact strength, coloration, and weight-average molecular weight of the resin constituting the molded article after molding were measured using the same methods as those used to evaluate the molded article in the above-mentioned injection-molded article production 1. The results are shown in the lower column of Table V.

[0243] [Table 3]

[0244] [Melt-spun fiber production] The crystalline cellulose resins in Table I and the additives shown in Table II were combined as shown in Table VI, and hot melt molded products 401 to 405 were produced as melt-spun fibers using a single-screw melt spinning machine by the following method.

[0245] (1) Preparation of pellets (resin composition) A powder was prepared as a mixture of crystalline cellulose resin 100, stabilizer 1, stabilizer 2, and additive RAa-9 in the same manner as in the preparation of the thermal melt molded product 201. The obtained powder was kneaded and extruded in a twin-screw kneader, and pelletized in a cold cutter pelletizer, in the same manner as in the thermal melt molded product 201, to prepare pellets.

[0246] (2) Melt spinning The pellets (resin composition) prepared above were melted using a single-screw melt spinning machine at a melter temperature of 210°C and extruded at a discharge rate of 5.9 g / min through a die having six 0.23 mmφ x 0.30 mmL die holes and a pack temperature of 220°C. The pack temperature corresponds to the temperature of the resin composition immediately after being extruded from the die holes and is the maximum temperature (T3) during molding.

[0247] The spun yarn was cooled by chimney air at 25°C, and after being applied with an oil and converged, it was taken up by a first godet roller rotating at 450 m / min, passed through a second godet roller rotating at the same speed as the first godet roller, and wound on a winder rotating at a speed giving a winding tension of 0.1 cN / dtex. The obtained fiber was named hot-melt molded product 401.

[0248] Similar to the above-mentioned hot melt molded product 401, hot melt molded products 402, 403, and 404 were produced by changing some of the conditions as shown in Table VI. In addition, for the hot melt molded product 405, spinning from the spinneret was not possible, and a hot melt molded product (fiber) could not be produced.

[0249] (3) Evaluation The mechanical properties of the hot melt molded articles (fibers) obtained above were evaluated by the strength and elongation at break measured in a tensile test carried out in accordance with JIS L1015 as follows. The results are shown in the lower columns of Table VI.

[0250] (strength and elongation) Tensilon UCT-100 (manufactured by Orientec Co., Ltd.) was used to perform tensile tests at a sample length of 20 cm and a tensile speed of 20 cm / min. The stress at the point of maximum load was taken as the fiber strength (cN / dtex). The elongation at break was taken as the fiber elongation (%).

[0251] The hot-melt molded product 401 had extremely good spinnability, with absolutely no yarn breakage observed. The resulting fiber had a strength of 1.0 cN / dtex and an elongation of 38%. Furthermore, the single yarn fineness evaluated in accordance with JIS L1095 was 21.9 dtex and U% was 0.7%. An attempt was made to produce a knitted fabric from the resulting fiber (hot-melt molded product 401) using a cylindrical knitting machine (MR1 cylindrical knitting machine, 27 gauge, manufactured by Maruzen Sangyo Co., Ltd.), and the knitting was good, resulting in a knitted fabric with a soft texture.

[0252] [Table 4]

[0253] From the above results, it is clear that the resin composition of the present invention has excellent hot melt moldability and also retains the good physical properties of the cellulose resin in the hot melt molded article obtained. [Industrial Applicability]

[0254] According to the present invention, it is possible to provide a resin composition containing a cellulose resin that has excellent hot-melt moldability and is capable of retaining the good physical properties of the cellulose resin in the resulting hot-melt molded article.It is also possible to provide a hot-melt molded article retaining the good physical properties of the cellulose resin and a molding method therefor.

Claims

1. A resin composition for hot melt molding containing a crystalline cellulose resin as a main component, Contains an additive that satisfies the following formula (1): the additive is any one of the following compounds RAa-1, RAa-9, and RB-3, The resin composition is characterized in that the crystalline cellulose resin is a crystalline cellulose ester resin, in which the degree of substitution of hydrogen atoms for hydroxy groups in the crystalline cellulose ester resin is 2.7 or more and the degree of substitution of acetyl groups in the crystalline cellulose ester resin is 2.7 or more. Formula (1) T2≦T1×0.93 In formula (1), T2 represents the melting point [°C] of a mixture in which 10 parts by mass of the additive is added to 90 parts by mass of the crystalline cellulose resin, and T1 represents the melting point [°C] of the crystalline cellulose resin alone. 【Chemistry 1】

2. The resin composition according to claim 1, wherein the difference between T1 and T2 is 25°C or more.

3. The resin composition according to claim 1 or 2, wherein the additive satisfies the following (i), (ii), or (iii) in the following formula (2): (i) Vu / V1<1.0 and χ<3 (ii) 1.0≦Vu / V1<1.5 and χ<6 (iii) 1.5≦Vu / V1 and χ<8 Equation (2) 1 / Tm - 1 / Tm ０ = (R / ΔHu) × (Vu / V1) × (ν １ - χν １ ２ ) In formula (2), the symbols have the following meanings. Tm: melting point (absolute temperature) of a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin Tm ０ : Melting point (absolute temperature) of the crystalline cellulose resin alone R: gas constant ΔHu: Heat of fusion per mole of the repeating unit forming the crystalline cellulose resin V1: molar volume of the additive Vu: the molar volume of the repeating unit forming the crystalline cellulose resin ν １ : Volume fraction of the additive in a mixture obtained by adding 10 parts by mass of the additive to 90 parts by mass of the crystalline cellulose resin χ: a parameter indicating the interaction between the crystalline cellulose resin and the additive

4. A hot melt molded product made from the resin composition according to any one of claims 1 to 3.

5. A molding method for hot melt molding the resin composition according to any one of claims 1 to 3, The molding method comprises carrying out the hot melt molding under conditions that satisfy the following formula (3): Formula (3) T3≦T1×0.75+20 In formula (3), T3 represents the maximum temperature [°C] of the resin composition during hot melt molding.

6. The molding method according to claim 5, which is injection molding, extrusion molding, or fused deposition modeling.

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