JP3691384B2 - Method for producing cross-linked polyethylene foam with tourmaline ore - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a cross-linked polyethylene foam, and relates to a cross-linked polyethylene foam obtained by mixing tourmaline ore into a resin and generating a large amount of negative ions, and a method for producing the same.
[0002]
[Prior art]
In recent years, tourmaline has attracted attention as a material for various therapeutic effects of negatively charged ions, environmental improvement or health improvement. Furthermore, negative ions are also known to have antibacterial and deodorizing effects. However, even if negative ions have a therapeutic effect, for example, negative ion generators or devices are expensive, and are only widely used in some hospitals and have not yet been widely spread.
[0003]
[Problems to be solved by the invention]
In general, tourmaline ore called tourmaline is a polar crystal, causing electric polarization without being placed in an electric field, and negative ions that exist in nature are attracted to the tourmaline ore plus electrode, It is known that electrons constantly flow from the negative electrode toward the positive electrode, and negative ion electrons are emitted from the negative electrode. Paying attention to such a phenomenon, attempts have been made to use tourmaline powder as an underwear, a supporter, etc. by coating the fiber with a fiber or by weaving and kneading the fiber. Furthermore, it is also used as a facial cosmetic by kneading it into cosmetic materials. However, the amount of negative ions generated in tourmaline ore is extremely weak, and at present, sufficient effects are not obtained.
[0004]
For example, Japanese Patent Application Laid-Open No. 11-021384 discloses rubber elasticity obtained by blending 1 to 100 parts by weight of 0.1 μm to 1 mm tourmaline ore with 100 parts by weight of styrene butadiene rubber, ethylene propylene diene rubber or silicone rubber alone. A composition is disclosed. However, due to sulfur vulcanization, the sulfur odor remained and the vulcanization was uneven, resulting in large variations in the resulting bubbles.
[0005]
[Means for Solving the Problems]
The method for producing a tourmaline ore-containing crosslinked polyethylene foam of the present invention comprises 5 parts by weight of tourmaline ore having a particle size of 0.1 μm to 1 mm for generating negative ions , 100 parts by weight of polyethylene resin, 2 to 2 azodicarbonamide. 20 parts by weight, a foamable resin composition containing zinc white and zinc stearate as a crosslinking agent foaming aid is filled in a mold, which is sealed under pressure and at 130 to 170 ° C. for 25 to 40 minutes. This is a method of heating, decomposing the foaming agent and the crosslinking agent, and taking out the foam after removing the pressure .
[0006]
The method for producing a tourmaline ore-containing cross-linked polyethylene foam according to the present invention is obtained by blending 100 parts by weight of a polyethylene resin with 5 to 50 parts by weight of a tourmaline ore having a particle size of 0.1 μm to 1 mm, a foaming agent and a cross-linking agent. The resin composition is heated and foamed.
[0007]
As the tourmaline ore used in the present invention, a shoal tourmaline, a lithium tourmaline, a driverite tourmaline, a rubellite tourmaline, a pink tourmaline, an indecolite, a paraba tourmaline, a water melon, etc. can be used, and a shoal tourmaline called a black tourmaline is particularly preferable. .
[0008]
By setting the particle size of the tourmaline ore within the above range, the surface area can be expanded to generate a large amount of negative ions, and the compatibility with the resin is excellent, and holes are hardly generated in the obtained foam. .
[0009]
When the number of added parts of tourmaline ore is less than the above range, the generation of negative ions is small, and when it exceeds the above range, the elongation of the resin is inhibited and adversely affects foaming.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the suitable aspect is demonstrated concretely about the manufacturing method of the crosslinked polyethylene type foam containing a tourmaline ore concerning this invention.
[0011]
(Pressurized one-stage foaming)
Mixing by adding 5 to 50 parts by weight of tourmaline ore powder, 2 to 10 parts by weight of a foaming agent, a crosslinking agent and, if necessary, a foaming aid, a filler and a pigment to 100 parts by weight of a polyethylene resin Mix by roll, pressure kneader, extruder, etc. The mixture is filled in a mold, sealed under pressure, and heated at 120 to 180 ° C., preferably 130 to 170 ° C. for 10 to 50 minutes, preferably 25 to 40 minutes. After decomposing and depressurizing, the foam is taken out.
[0012]
(Two-stage foaming method)
A mixing roll in which 5 to 50 parts by weight of tourmaline ore powder, 5 to 20 parts by weight of a foaming agent, a crosslinking agent and, if necessary, a foaming aid, a filler and a pigment are added to 100 parts by weight of a polyethylene resin and heated. Mix with a pressure kneader or an extruder. The mixture is filled in a mold, sealed under pressure, and heated at 120 to 180 ° C., preferably 130 to 170 ° C. for 10 to 50 minutes, preferably 25 to 40 minutes. Partially disassemble and decompress, take out the intermediate foam from the mold, then place the intermediate product in a non-sealing mold corresponding to the shape and dimensions of the final product, and heat the jacket on the mold By heating through a medium and heating at 140 to 200 ° C., preferably 150 to 170 ° C. for 10 to 60 minutes, preferably 20 to 40 minutes, the remaining foaming agent is decomposed and foamed. A uniform foam is obtained.
[0013]
The polyethylene resin used in the present invention is a high pressure method low density polyethylene, a low pressure method low density polyethylene (including metallocene), medium density polyethylene, high density polyethylene, ethylene-vinyl acetate copolymer, ethylene-butene copolymer, ethylene And copolymers of methyl, ethyl, propyl or butyl alkyl acrylates. Two or more of these may be used in combination.
[0014]
As a foaming agent used in this invention, what has a decomposition temperature more than the flow start temperature of said base resin can be used. For example, azodicarbonamide, dinitrosopentamethylenetetramine and the like can be mentioned. In the present invention, in order to lower the decomposition temperature of the foaming agent, metal oxides such as zinc oxide and lead oxide, compounds mainly composed of urea, lower or higher fatty acids, or metal salts of lower or higher fatty acids, etc. A foaming auxiliary agent can also be added.
[0015]
Examples of the crosslinking agent used in the present invention include dicumyl peroxide, 2,5-dimethyl-2,5-ditertiary butyl peroxyhexane, 2,3,5-dimethyl-2,5-ditertiary butyl peroxyhexane. , Α, α-ditertiary butyl peroxydiisopropylbenzene and the like can be used. Moreover, although a crosslinked state can be adjusted also with the addition amount of a crosslinking agent, since this changes with kinds of resin, it is necessary to adjust an addition amount suitably.
[0016]
In the present invention, for the purpose of improving the physical properties of the composition to be used or reducing the price, there is no significant adverse effect on the cross-linking (filler), such as zinc oxide, titanium oxide, calcium oxide, magnesium oxide, silicon oxide, etc. Metal oxides, carbonates such as magnesium carbonate and calcium carbonate, fiber materials such as pulp, various dyes, pigments, fluorescent materials, and other conventional rubber compounding agents can be added as necessary.
[0017]
【Example】
EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.
[0018]
Example 1
Low-density polyethylene (trade name “NOVATEC LD YF30”, melt flow rate 1.1 g / 10 min, density 0.920 g / cm ³ , manufactured by Nippon Polychem Co., Ltd.) 100 parts by weight, tourmaline powder 10 parts by weight, azodicarbonamide A resin composition comprising 6.0 parts by weight, zinc white 2.0 parts by weight, zinc stearate 0.5 parts by weight and dicumyl peroxide 0.6 parts by weight is kneaded with a 100 ° C. mixing roll. A mold (195 × 380 × 28 mm) in a press heated to 0 ° C. was filled with the kneaded product and heated under pressure for 35 minutes to obtain a foam.
[0019]
The obtained foam had an apparent density of 0.064 g / cm ³ .
[0020]
Example 2
In Example 1, 100 parts by weight of a polyethylene resin polymerized using a metallocene catalyst (trade name: Kernel KS240, density 0.88 g / cm3, MFR: 2.2 g / cm3, manufactured by Nippon Polychem Co., Ltd.) Except having changed, the foam was obtained with the same composition and the same conditions as Example 1.
[0021]
The obtained foam had a density of 0.062 g / cm ³ .
[0022]
Example 3
In Example 1, a foam was obtained with the same composition and the same conditions as in Example 1 except that the tourmaline ore powder was changed to 40 parts by weight.
[0023]
The obtained foam had an apparent density of 0.071 g / cm ³ .
[0024]
Comparative Example 1
In Example 1, a foam was obtained under the same composition and the same conditions as in Example 1 except that the tourmaline ore powder was changed to 2 parts by weight.
[0025]
The obtained foam had an apparent density of 0.058 g / cm ³ and had almost no effect of emitting negative ions.
[0026]
Comparative Example 2
In Example 1, except that the tourmaline ore powder was changed to 60 parts by weight, foaming was carried out under the same composition and the same conditions as in Example 1, but a large amount of tourmaline ore powder hindered the elongation of the resin and was a satisfactory foam. Was not obtained.
[0027]
【The invention's effect】
As described above, the tourmaline ore-containing cross-linked polyethylene foam of the present invention and the production method thereof generate a large amount of negative ions, can maintain the effect for a long time, do not generate a sulfur odor, and Because of its excellent elasticity, it has excellent effects as a health treatment tool and deodorant product. In particular, the use of metallocene polyethylene as a base material is suitable as a mouse pad or the like that is excellent in flexibility and generates a large amount of negative ions.

Claims (1)

100 parts by weight of a polyethylene resin, 5-50 parts by weight of tourmaline ore having a particle size of 0.1 μm to 0.1 mm that generates negative ions, 2-20 parts by weight of azodicarbonamide, a cross-linking agent, zinc white as a foaming aid, and Fill the mold with a foamable resin composition containing zinc stearate , seal it under pressure, heat it at 130-170 ° C. for 25-40 minutes, decompose the foaming agent and crosslinking agent, and release the pressure Then, the manufacturing method of the crosslinked polyethylene type foam containing a tourmaline ore which takes out a foam .