JPS6357671A - Filler for resin molding - Google Patents

Abstract

PURPOSE:To obtain a filler which has excellent dispersibility in resin and an improved property with respect to wear during the blending thereof with resin, by applying an org. lubricant to the surfaces of specified silica/alumina particles which are amorphous in X-ray diffractometry. CONSTITUTION:A filler is composed of silica/alumina particles (a) which have a chemical composition of Al2O3:SiO2 in a molar ratio of 1:1.8-1:5, whose primary particle has definitely a cubic or spherical shape and a diameter of not large than 5mu as determined by electron microscopy and which have a specific surface area according to the BET method of not smaller than 100m<2>/g and are amorphous in X-ray diffractometry and 0.01-30wt% (based on the amount of the particles) org. lubricant (b) applied to the surfaces of the particles. The amorphous alumina/silica particles can be prepd. by neutralizing crystalline zeolite having a cubic or spherical particle shape under such conditions that its crystalline structure is broken, but its particle shape is retained to remove alkali metal components in the zeolite.

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention is directed to the use of silica to be added to molded products such as resin films.
The present invention relates to improvements in alumina fillers, and more particularly to silica-alumina fillers that have excellent dispersibility in resins and eliminate the problem of abrasion when blended into resins.

(Prior art) Resin molded products such as films tend to block each other when stacked, and in order to prevent this, it has long been a practice to mix various inorganic additives into the resin. It is being done.

It is already known that zeolite is excellent in such properties. For example, in Japanese Patent Publication No. 52-18134, 0.01 to 5% by weight of zeolite powder with an average particle size of 20 microns or less is added to polypropylene. It has been shown that the blocking resistance of biaxially oriented polypropylene films can be improved by doing so. Also, JP-A-5
No. 4-34356 discloses that an aluminosilicate of zeolite crystals having ion-exchange properties is added to a chlorine-containing polymer by 0.00%.
It has been disclosed that the thermal stability can be improved by incorporating amounts of 0.01 to 10% by weight, and that the external slipperiness is significantly improved as an additional advantage here.

As mentioned above, zeolite particles are excellent in providing slip properties (external lubricity) and anti-blocking properties to resin molded products, but zeolite contains sodium content in the form of aluminosilicate. , potassium, calcium, magnesium, and other basic components, and the presence of these basic components poses an economical problem in that resin molded products containing zeolite particles become colored. In addition, zeolite generally contains crystal water called zeolite water, and this crystal water is released under resin processing or molding conditions.

This causes a so-called foaming problem.

As a solution to this problem, Japanese Unexamined Patent Publication No. 58-2130
Publication No. 31 states that the molar ratio of Al2O3:SiO2 is t
: Consisting of cubic-order particles with a side length of 5 microns or less, having a composition in the range of t, S to 1:5, which particles are substantially amorphous in X-ray diffraction and 100 m''
An alumina-silica resin compound is described which is characterized by having a BET specific surface area of 0.25% or less.

(Problems to be Solved by the Invention) This amorphous silica-alumina compound has a constant particle shape and particle size, and provides good slip properties and 7-inch broaching properties to the film molded product in which it is compounded. However, there are still problems to be solved regarding blending and dispersion into resins.

That is, this silica-alumina compound has properties as an abrasive and a polishing agent like many silicate compounds. Thus, when dry mixing this compounding agent and resins using a Henschel mixer, etc., or melt-kneading them using a niegu, roll, extruder, etc., the walls of the mixing device or mixing device, stirring blades, screws, etc. There is a tendency to wear out the agent.

The amorphous silica alumina compound mentioned above.

This is completely different from ordinary fillers, in which fine primary particles aggregate to form secondary particles that are easy to break mechanically.
Since the secondary particles themselves are the final particles (secondary particles) and have a distinct shape such as a cube, it is thought that the abrasion tendency in the mixing or kneading equipment is noticeable.

Furthermore, in general, regarding the relationship between the dispersion state of inorganic compounding agents in resin and the physical properties of molded products, the more even and uniform the dispersion state of compounding agents, the better the mechanical properties such as elongation and impact resistance. It is also known that properties such as slip properties and anti-blocking properties are good, and from this point of view, the compounding agent used is one that is evenly and uniformly dispersed in the resin within a relatively short period of time. This is desirable.

Therefore, the present invention eliminates the above-mentioned drawbacks of conventional amorphous silica-alumina compound, eliminates the tendency to wear when mixed with resin or cross-wires, and moreover, dissolves into the resin uniformly within a relatively short time. Another object of the present invention is to provide an amorphous silica-alumina compound that has the property of uniformly dispersing.

(Means for Solving the Problems) According to the present invention, a chemical composition in which the molar ratio of AAz03:SiO2 is in the range of 1:1.8 to 1:5, a clear cubic to spherical primary particle shape, and , X-ray diffractically substantially amorphous silica-alumina particles (hereinafter simply referred to as regular amorphous particles) having an electron microscopy primary particle diameter of 5 microns or less and a BET specific surface area of less than The above object can be achieved by applying a limited amount of organic lubricant, that is, 0.01 to 30% by weight per particle, on the surface of the silica-alumina particles. can.

(Function) The present invention is characterized in that a limited amount of organic lubricant applied to the surface of regular-amorphous silica-alumina particles maintains good penetration into the resin during kneading, and also maintains good penetration into the resin. This is based on the knowledge that it acts to significantly reduce the tendency of wear during mixing or cross-talk.

In general, lubricants are used to improve fluidity and facilitate processing when thermoplastic resins are heated and molded.
Alternatively, it is defined as an agent added to make it easier to remove the molded product from the mold (release from the mold). However, in the present invention, the lubricant applied to the surface of the regular-amorphous silica-alumina particles acts to significantly reduce the wear of the mixing device or kneading device caused by the particles, and this fact can be avoided. will become immediately clear by reference to the examples below.

In addition, generally when the surface of filler particles is treated with a lubricant,
When kneading the resin and filler, there is a tendency for the resin to eat into the filler poorly. The degree of this penetration can be evaluated by, for example, supplying a composition of vinyl chloride resin and filler to a plastograph tester and measuring the time from the start of crosstalk to the start of torque increase. With a good filler, the time until this rise is short,
This time is long for fillers with poor penetration. This is because while the lubricant on the particle surface effectively prevents wear on mixers and kneaders, when kneading with resin, the particle shape has a greater effect. It is presumed that this is due to the following.

Moreover, the lubricant present on the particle surface acts to promote even and uniform dispersion of the compounding agent particles into the resin.

The fact that the dispersion of the compounding agent is uniformly and evenly carried out on each side of the particles is confirmed by observing the resulting compounded resin film with an electron microscope.

The amount of lubricant applied to the surface is 0.01 to 30% by weight.

In particular, the range of 1.0 to 10% by weight is also critical; if it is less than this range, there is no wear prevention effect, and if it is more than the above range, there is a tendency for poor penetration into the resin. is remarkable.

(Preferred embodiment of the invention) Silica-alumina particles The alumina-silica resin compound used in the present invention is At
The molar ratio of 203:5iOz is 1:1.8 to 1:
5, especially having a composition in the range 1:2 to 1:4.

A12o3:5t (if the molar ratio of h is outside the above range,
It is difficult to make this alumina-silica into cubic or spherical particles with a clear and constant particle size, and furthermore, properties such as slip properties are inferior to those within the scope of the present invention.

In this alumina-silica particle, 3
The moisture content, defined as loss on ignition in 0 minutes, is generally in the range below 30%, especially below 10%. This water content varies depending on the manufacturing conditions of the alumina-silica particles, and the water content is in the range of 1 to 30% for particles as-manufactured by the method detailed later, but when dried or As the firing temperature increases, the water content gradually decreases. For the purpose of the present invention, alumina-silica particles having a low water content are generally suitable.

The alumina-silica compound used in the present invention is as follows.

In addition to the essential components of alumina and silica, it is permissible to contain some basic components, especially alkali metal components. However, the content of this alkali metal is Atz
03:! 50% or less, especially 30% of the alkali metal content of the zeolite in which the molar ratio of 9i02 is within the same range.
It should be noted that the content of basic components is significantly lower than that of zeolite.

A few examples, on a compositional weight basis, of particularly desirable alumina-silica formulations for the purposes of this invention are shown below.

1st type At20327~45% 5iOz 32~55% Na2O0,1~20% H2025% or less Type ■Aj! z0338~54% 5402 32~64% Na2O0,1~20% H2030% or less Type ■Aj! 20347-64% SiO238-78% Na2O0.1-20% [Below 2030% Conventionally, what is called amorphous zeolite is known. This amorphous zeolite is produced by aging and reacting a composition whose alumina content, silica content, alkali metal content, and water content are within the zeolite-forming range, and stopping the reaction before zeolite crystals begin to crystallize. , alumina content,
It contains silica and alkali metal in approximately the same proportions as crystalline zeolite. On the other hand, in the formulation used in the present invention, the alkali metal content is significantly lower than that of amorphous zeolite, and in this respect they can be clearly distinguished.

The alumina-silica resin compound used in the present invention also includes:
Although it is substantially amorphous in terms of X-ray diffraction, it exists as cubic to spherical particles with constant size and shape. In the attached drawings, Figure 1-A shows X of zeolite) A.
Figure 1-B is an X-ray diffraction diagram of the alumina-silica compound used in the present invention. Furthermore, Figure 2-A is an electron micrograph of zeolite) A (
Figure 2-B is an electron micrograph of this alumina-silica compound (magnification: 10.000 times).
times).

Conventionally, most amorphous alumina-silicas have amorphous primary particles, such as alumina-silica gel, whose primary particles have an amorphous shape. Not known to anyone other than the side.

In the formulation of the present invention, the cubic particles have a primary particle size with a side length of 5 microns or less, especially 1 micron or less, as measured by electron micrograph. From the viewpoint of preventing agglomeration of the compounding agent particles, it is desirable that the secondary particle size is 0.1 micron or more.

Furthermore, in conjunction with having the aforementioned particle morphology and particle size characteristics, the amorphous alumina-silica particles used in the present invention have a BET specific surface area of 100 rrI'/g or less, particularly 50 m''/g or less. That is, while ordinary amorphous alumina-silica has a specific surface area considerably larger than 100 m'/g, the alumina-silica cubic or spherical particles of the present invention have an extremely small specific surface area and are not easily bonded to resins. It is easy to mix wires, and there is little tendency to increase the melt viscosity when molding into films, sheets, etc., and it has excellent molding workability.

Furthermore, the formulation particles used in the present invention have a bulk density in a relatively large range of 0.3 to 0.73/cc in relation to the fact that they are cubic to spherical and have a relatively large primary particle size. For example, the bulk density is 1.5 times or more compared to that of known silica-based antiblocking agents, and it is extremely easy to blend into resins.

The amorphous alumina-silica particles used in the present invention are obtained by converting crystalline zeolite having a cubic to spherical particle shape under conditions in which the crystal structure is substantially destroyed but the particle morphology is not substantially damaged. It is produced by neutralizing with acid to remove the alkali metal content in the zeolite.

As the raw material crystalline zeolite, zeolite A, zeolite

The acid to be used may be an inorganic acid or an organic acid without particular limitation, but economically, acids such as hydrochloric acid, sulfuric acid, nitric acid, and phosphoric acid are used. These acids are used in the form of dilute aqueous solutions for the neutralization reaction with the crystalline zeolite.

When an acid is added to an aqueous slurry of crystalline zeolite, the pH naturally shifts to the acidic side as the acid is added, but after the addition is complete, the pH of the liquid tends to shift back to the alkaline side and become saturated at a certain pH value. . This saturation p)! , that is, the stable pH is 7.0 to 3.0. In particular, it is desirable for the purpose of the present invention to carry out the neutralization to a pH in the range of 8.5 to 4.0, i.e. when this pH is higher than the above range,
It becomes difficult to effectively remove the alkali content in the zeolite and make it amorphous. On the other hand, when the pH is lower than the above range, the alumina content in the zeolite also tends to be eluted, making it difficult to leave the cubic particle form. The amount of acid used is at least 50% of the alkaline content in the zeolite.
In particular, it must be sufficient to remove 70% or more. Non-quality alumina silicone cubic particles obtained by eluting and removing alkaline content through acid treatment are
If necessary, it is washed with water, dried, or further calcined as desired to obtain a resin compound. In the present invention, the surface of the particles is treated with a mechanical lubricant. As the organic lubricant, any known lubricant can be used, and suitable examples thereof are as follows. ■ Aliphatic hydrocarbon-based liquid paraffin Industrial white mineral oil synthetic paraffin Petroleum-based wax Petrolatum Odorless light hydrocarbon ■ Silicone organoborisiloxane ■ Fatty acids and their metal salts Higher fatty acids Fatty acids obtained from animal or vegetable oils and their hydrogenated fatty acids Higher fatty acid metal salts having 8 to 22 carbon atoms, alkali metal salts, alkaline earth metal salts, and Z
n salt, At salt ■ Amide, amine Higher fatty acid amide Oleyl palmitamide Stearyl erucamide 2 stearomide Ethyl stearate Ethylene bis fatty acid amide N 012
~C+s) Amide N-N'bis(hydroxyethyl)lauroaiido N alkyl (C+oNC+e)} Distearic acid ester of oleic acid fatty acid diethanolamine di(hydroxyethyl) diethylenetriamine monoacetate reacted with rimethylenediamine ■ of monohydric and polyhydric alcohols Fatty acid ester n-butyl stearate hydrogenated rosin methyl ester sebatin dibutyl n-butyl> dioctyl sebatate 2-ethylhexyl and n-octyl> glycerin fatty acid ester pentaerythritol tetrastearate polyethylene glycol fatty acid ester polyethylene glycol distearate polyethylene Glycol dilaurate polyethylene glycol dioleate polyethylene glycol coconut fatty acid diester polyethylene glycol tall oil fatty acid diester ethanediol montanic acid diester 1●3 butanediol montanic acid diester diethylene glycol stearic acid diester propylene glycol fatty acid diester ■ Triglyceride, wax hydrogenated Edible oils Cottonseed oil and other edible oils Linseed oil Palm oil Glycerin esters of l2-hydroxystearic acid Hydrogenated fish oil Beef tallow Sparm acetiwax Montan wax Carnauba wax Honey Wax Monovalent fatty acid alcohols and fatty acid saturated acid esters Examples: Hydrogenated whale oil Lauryl stearate, stearyl stearate> Lanolin■ Other propylene glycol alginate difurkyl ketone In the present invention, among various lubricants, per gram of lubricant, carboxylic acid, carboxylic acid anhydride, carboxylate,
Contains polar groups such as carboxylic acid esters, carboxylic acid amides, ketones, ethers, hydroxyl groups, etc. at a concentration of 0.5 to 20 mmol, especially 1 to 10 mmol, and has at least 10 carbon atoms, especially at least 1 carbon number from 12 to 18. It is desirable to use a lubricant containing long-chain alkyl groups in the molecule.
Such lubricants are readily available as fatty acids or fatty acid derivatives, fatty alcohols or derivatives thereof. Fatty acid amide-based lubricants are particularly desirable in view of the above-mentioned effects.

Furthermore, it is desirable that this lubricant has a melting point of 30°C or higher, particularly 50°C to 150°C, in terms of ease of handling during surface treatment, that is, fluidity as a powder and caking resistance. Suitable lubricants are ethylene bis fatty acid abids, such as ethylene bis stearamide.

L straight scale 1 regular amorphous silica-alumina particles and 0.01 to 30
The surface of the particles is lubricated by admixing with 1 to 10% by weight of a lubricant, which can be applied alone or in the form of a solution or dispersion. The mixing is preferably carried out using a grinding type mixer such as a Henschel mixer or a super mixer, which allows each particle to be uniformly surface-treated with a lubricant.

In addition, the surface-treated alumina-silica resin compound of the present invention may be one of various resins, such as olefin resins such as polypropylene, polyethylene, crystalline propylene-ethylene copolymers, and ionically crosslinked olefin copolymers; polyethylene terephthalate. , thermoplastic polyester such as polybutylene terephthalate; 6-nylon, 6.6-nylon, 6,
8- Polyamides such as nylon: chlorine-containing resins such as vinyl chloride resin and vinylidene chloride resin; polycarbonate;
Polysulfones: Can be used to impart slip properties or anti-blocking properties to resin molded products such as films by blending with thermoplastic resins such as polyacetal. Of course, instead of being blended into the resin after polymerization, it may be blended in advance into the monomer before one polymerization so that the blending agent is contained in the resin after polymerization.

For such applications, the amorphous alumina-silica cubic particles of the present invention are used in amounts of 0.001 to 10 parts by weight, particularly 0.01 to 3 parts by weight, per 100 parts by weight of resin.

(Operations and Effects of the Invention) According to the present invention, compounding agent particles for imparting slip properties or anti-blocking properties can be efficiently and uniformly mixed with a resin or prevented from being worn in a crosstalk device. The advantage is that the anti-blocking properties can be improved without impairing the mechanical properties, transparency, etc. of the resin molded product by uniformly dispersing it.

(Example) Reference Example 1 Type 4A zeolite powder synthesized according to Reference Example 2 described in JP-A-54-36356 (see Figure 2-B-1) 1
50Kg 2. C1rTN'0) was dispersed in water, and about 40 (l) of dilute sulfuric acid was slowly added under stirring.The amount of sulfuric acid at this time corresponded to about 0.8 mol of the total amount of Na2O in the zeolite.After the addition of sulfuric acid was completed, It was suction filtered and thoroughly washed with water.

The mixture was then dried for 48 hours in a large-shelf electric dryer at 110°C, then fired in a firing furnace for about 1 hour, and then pulverized and classified in a conventional manner to obtain an amorphous spherical aluminosilicate powder.

An electron micrograph of this product is shown in Figure 2-B-2.

Table 1 shows the physical properties of the powder.

The test method in this reference example was as follows.

(1) Packing density Based on JIS-6220.

(2) Specific surface area Measured by BET method.

(3) Oil absorption amount Based on JIS@-5101.

(4) Whiteness Based on JIS-8123.

(5) Particle size sample for electron microscopy Take an appropriate amount of fine powder onto a metal sample plate, disperse it thoroughly, coat it with metal using a metal coating device (Hitachi model E-101 ion sputter), and use it as a photographic sample. Next, scan using a conventional method. Using a microscope (Hitachi model S-570), the field of view was changed to obtain four 10,000x electrophotographic images suitable for primary particle measurement.

Six representative particles were selected from among the cubic particle images in the field of view, and the length of one side of each cubic particle image was measured using a scale, and the length was expressed as the primary particle diameter in the Reference Example herein.

(6) Crystal morphology using X-rays Measured using an X-ray diffraction apparatus manufactured by Denki Co., Ltd. under the following conditions.

(Apparatus) Rigaku Denki X-ray diffractometer goniometer PMG-32 Rate meter ECP-02 (Measurement conditions) Target Cu Filter Ni Voltage 35KV Current 20mA Count full scale 4X103C/S time constant
1 sec Chart speed 1cm/win Scanning speed 1°/! lin radiation angle 1° Slit width 0.15 mm Measurement range 2θ = 20° ~ 32° (7) Particle size distribution Micro Fort Sizer 5KN-ioo manufactured by Seishin Enterprises
A 0.2% sodium birophosphate aqueous solution is used as the dispersion medium for the measurement using the o-type. At the beginning of the measurement, the zero point and swing width of the recorder are adjusted using only the dispersion medium.The amount of light transmitted through the blank is adjusted to Log 1.95 of the recording paper.

The sample dispersion liquid was prepared as follows.

Take a 200mp00m beaker and 10om/j, add a sample of 15mg, and S K D 1sperser.
Disperse for 2 minutes using an ultrasonic disperser. At this time, after the dispersion is completed by stirring for 1452 hours with a stirrer, the liquid is cooled or heated until it reaches a predetermined temperature. This dispersion liquid is poured into the glass cell up to the marked line while maintaining a uniformly dispersed state. When the cell is set in the cell holder and the light source lamp is turned on, if the pen of the recorder is between Logl, 3 and Log1.4, the concentration of the dispersion liquid is appropriate. Logl
, if it is less than 3, it is too dark, and if it is more than 4, it is too thin, so readjust it. Jlll constant is maximum particle size 30
This will be done under the conditions of JL.

Reference Example 2 Amorphous aluminosilicate was obtained by carrying out the same treatment as in Reference Example 1 using Mizusawa Chemical's Mizuriki Sieves 4AP (see Figure 2-B-3).

An electron micrograph of this product is shown in Figure 2-B-4, and the physical properties of the powder are shown in Table 1.

Table 1 Example 1 2 kg of the amorphous aluminosilicate obtained in Reference Example 1 was mixed with calcium stearate (NOF SC) as shown in Table 2.
), ethylene bisstearamide (KAO-WAX
EB-F), polyethylene glycol (NOF P
Add a predetermined amount of EG 4,000) and mix it with a super mixer (
NI)ION 5PINDLE MFGCo:LTD
The surface treatment was carried out for 30 to 40 minutes using a coating material (type VNM 5AL), and the abrasion properties were measured.

Abrasion resistance is measured using lead plates, copper plates, iron plates with different Mohs hardness,
Stainless steel plate with a thickness of 1 to 1.5 m/m and a diameter of 5 to 6 cm.
(20 to 35 g in weight) of the same shape was made, attached to a Homo Mixer, and submerged into 11 fixed ointment bottles filled with the measured powder to 70% of the total volume. Abrasion properties were compared based on the weight reduction rate when rotated at 4.00 Or, p, m for 2 hours.

Example 2 The amorphous aluminosilicate powder obtained in Reference Example 2 was treated in the same manner as in Example 1, and its abrasion properties are shown in Table 3.

Example 3 The samples surface-treated in Examples 1 and 2 were blended with vinyl chloride resin and subjected to a lubricity test using a plastograph.

Compounding conditions: EP-103 (PVG) 100
PHR di-salt dibasic acid lead sulfate 0.5
tt lead stearate 1. Q tp test
Fee 1. Q //Plastograph condition OiL Temp
200℃ Rotor rotation speed 4
Or, p, m resin amount 8
1gr results are shown in Table 4.

Table 4 Note G, T, time to reach maximum torque (win
) M, T, Torque (Kg-i) Application example 1 Samples surface-treated in Examples 1 and 2 on low-density polyethylene with a melt flow index of 2.0 g/10 win and a density of 0.925 g/cc are shown below. The composition shown in No. 5 was melt-kneaded using an extruder at a temperature of 190° C. and then pelletized.

Separately, products without synthetic silica and inorganic additives were prepared in the same manner.

Next, the pellets were fed into an extruder and extruded into a tube at 180° C. to form a film with a thickness of 30 JL, and the film was measured for haze, blocking properties, slipperiness, and scratch resistance.

The results are shown in Table 5.

(1) Haze according to ASTM-D-1003 (2) Layer two blocking films together, apply a load of 20, leave in an oven at 40°C for 24 hours, and then measure the force required to peel off the two films. and has blocking properties.

(3) Slipperiness Based on ASTM-D-1894 (4) Scratchability The degree of scratching when two films are stacked and rubbed with a finger is compared. Evaluation method: ○ No scratches O Slight scratches Δ Slight scratches × Scratches As can be seen from the results in Table 5, the surface of amorphous silica-alumina particles treated with an organic lubricant is It is understood that it has excellent haze, blocking properties, and slip properties.

Furthermore, it can be seen that the scratch resistance is significantly improved.

Patent Applicant: Mizusawa Chemical Co., Ltd. and subsequent procedural amendments (blind motion) November 26, 1985 Commissioner of the Patent Office Kuro 1) Akio Yu 1, Indication of the Case 1986 Patent Application No. 201824 2, Invention Name Filler for resin molded products 3. Person making the amendment Relationship to the case Patent applicant 4. Agent address: 105 5. Date of amendment order October 28, 1985 (shipment date) 6. 10 inventions subject to amendment Detailed explanation column (1) On page 12, line 2 of the specification, "Figure 2-A" is corrected to "Figure 2-B-1 and Figure 2-B-3."

(2) On page 12, line 3, "Figure 2-B" is corrected to "Figure 2-B-2 and Figure 2-B-4 1."

■0 Brief Description of Drawings Column (1) Add the following statement after line 6 on page 37 of the specification.

[Brief explanation of drawings]

Figure 1-A is an X-ray diffraction diagram of zeolite A (α for Cu-), Figure 1-B is an X-ray diffraction diagram of the alumina-silica compound used in the present invention, and Figure 2-B- Figures 1 and 2-B-3 are electron mirror photographs (magnification: 10,000) of the particle structure of zeolite A, respectively.
0x) Figures 2-B-2 and 2-B-4 are electron micrographs (magnification: 1
0,000 times). ” Procedural amendments stamped June 19, 1988

Claims (4)

[Claims] (1) The molar ratio of Al_2O_3:SiO_2 is 1:1.
X having a chemical composition in the range of 8 to 1:5, a well-defined cubic to spherical primary particle shape, an electron microscopy primary particle diameter of 5 microns or less, and a BET specific surface area of 100 m^2/g or less - A resin molding characterized by comprising silica-alumina particles that are substantially amorphous in terms of linear diffraction, and an organic lubricant applied to the surface of the particles in an amount of 0.01 to 30% by weight per particle. Filler for products. (2) Claim 1, wherein the organic lubricant is an organic compound containing 0.5 to 20 mmol per gram of a polar group and at least one long-chain alkyl group having 12 or more carbon atoms in the molecule. Filler as described in section. (3) The filler according to claim 1, wherein the organic lubricant has a melting point of 30° C. or higher. (4) The filler according to claim 1, wherein the organic lubricant is ethylene bis fatty acid amide.