JP2002257810A - Material for detecting resin degradation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a material for detecting degradation of a resin whereby the degradation can be detected before a change in characteristics of the resin becomes apparent. SOLUTION: There is provided the material for detecting the resin degradation, which is constituted of at least (a layer A) as a degradation adjustment layer which degrades interlockingly with the degradation of a resin molding to be detected, and (a layer B) as a color change layer which contains a pigment which changes the color through oxidation and a resin degradation accelerator in a matrix of the same material as a material of the resin molding to be detected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel resin deterioration detecting material, and more particularly to a resin deterioration detecting material capable of detecting deterioration of a resin before a characteristic change becomes remarkable.

[0002]

2. Description of the Related Art Some resin products, such as engineering plastics, have obtained strength comparable to that of metal materials, and are currently formed into various shapes and used in various fields. On the other hand, in recent years, product safety, reliability, product liability (PL), and environmental issues have been widely discussed, and gas pipes, water pipes, and other pipe materials and their coatings have been used during the Great Hanshin Earthquake. In place of damaged steel pipes, resin products that have proven to be non-damaged have grown significantly in demand as structural materials. In addition, due to environmental pollution problems such as dioxins, in the packaging and cosmetics industries, instead of conventional vinyl chloride, a holistic transition to polyolefin-based materials such as polyethylene and polypropylene, which do not generate harmful substances during waste disposal. Is progressing.

[0003] Further, with the innovation of IT technology, higher-speed communication networks are expected, and as one of them, securing of an information communication infrastructure using optical fibers is being realized. The above-mentioned polyolefin-based resin has attracted attention also in such a coated tube material for coating an optical fiber.

However, deterioration of the polymer material is unavoidable due to environmental factors such as air, water, environmental pollution and microorganisms, and energy factors such as heat, light, electricity, and radiation. Specifically, such deterioration causes a change in molecular structure, chemical structure, and higher-order structure, and changes in characteristics such as physical characteristics, chemical characteristics, appearance, mechanical characteristics, and electrical characteristics.

[0005] In general, a polyolefin-based resin is inevitably subjected to thermal deterioration and light deterioration due to exposure to heat or light such as ultraviolet rays. More specifically, taking a polyethylene resin as an example, free radicals are generated in carbon-carbon bonds of polyethylene by heat or ultraviolet rays, and when this reacts with oxygen molecules, peroxy radicals are generated. Peroxy radicals play a leading role in the autoxidation reaction, and further attack polyethylene, generating radicals again with unstable hydroperoxides. This process becomes a chain reaction, in which the molecular weight is reduced due to the main chain cleavage, and gelation due to the crosslinking reaction proceeds. When the progress is stopped, various forms of radicals collide and become stable products. The carbonyl group generated at the end of the resin by the above reaction is detected by the absorbance of the carbonyl group in infrared absorption, and serves as an index of resin deterioration. FIG. 1 illustrates the above mechanism.

As the resin deteriorates, the carbon-carbon bond is broken, and the morphology in the polymer is changed due to a crosslinking reaction between the broken molecules. This change causes a decrease in the mechanical strength of the resin. Macroscopically, this deterioration causes cracks on the surface and inside of resin products such as gas pipes, water pipes, and optical fiber coating pipes, and has a great effect.

[0007] Accordingly, it is important to predict the life of a polymer material in various use environments in response to a large increase in demand for the polymer material.

[0008]

However, at present, it is difficult to accurately predict the life of such a polymer material, and the life is predicted by a deterioration promotion test with the highest possible reliability. , The fact. Many studies have been conducted on the degradation of polyethylene due to light and heat exposure, for which demand is increasing, but none of these studies focus only on the reaction mechanism. Absent. Therefore, in order to detect the deterioration of the resin beforehand and to be able to replace the deteriorated portion, it is necessary to develop a means for accurately knowing the deterioration time. Therefore, an object of the present invention is to provide a resin deterioration detection material capable of predicting a deterioration time.

[0009]

Means for Solving the Problems In view of the above, the present inventor has made intensive studies and as a result, has conceived a resin deterioration detecting material capable of knowing in advance the timing of resin deterioration. That is, the resin deterioration detection material according to the present invention includes at least a layer containing a pigment whose color changes and a resin deterioration adjusting agent in a matrix of the same material as the resin molded product to be detected.

[0010] In another aspect of the resin deterioration detecting material of the present invention, at least (A layer) a deterioration adjustment layer that deteriorates in conjunction with deterioration of the detected resin molded article, and (B layer) a detected resin molding. It is composed of a matrix of the same material as the body and a color change layer containing a pigment that changes color and a resin deterioration accelerator.

Further, the color-changing pigment may be a fading pigment.

[0012] Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjustment layer which deteriorates in conjunction with deterioration of the detected resin molded article, and (C layer) a detected resin molded article. In a matrix of the same material as the above, a color-changing layer containing a pigment and a resin deterioration accelerator whose color fades,
(D layer) a labeling layer containing a labeling pigment.

Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjusting layer which deteriorates in conjunction with deterioration of a detected resin molded article, and (C layer) a detected resin molded article. A color-changing layer containing a fading pigment and a resin deterioration accelerator in a matrix of the same material as that of (E layer)
Labeling Layer Protecting Layer (D Layer) A labeling layer containing a labeling pigment, and the like.

Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjusting layer which deteriorates in conjunction with deterioration of the detected resin molded article, and (C layer) a detected resin molded article. A color-changing layer containing a fading pigment and a resin degradation accelerator in a matrix of the same material as (D layer)
Labeling layer containing labeling pigment, (F layer) color adjusting layer (I)
In order.

Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjusting layer which deteriorates in conjunction with deterioration of a detected resin molded article, and (C layer) a detected resin molded article. A color-changing layer containing a fading pigment and a resin degradation accelerator in a matrix of the same material as (G layer)
A color adjusting layer (II) (D layer) and a labeling layer containing a labeling pigment.

[0016] Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjusting layer which deteriorates in conjunction with deterioration of the detected resin molded article, and (C layer) a detected resin molded article. A color-changing layer containing a fading pigment and a resin degradation accelerator in a matrix of the same material as (G layer)
The color adjusting layer (II), the (D layer) labeling layer containing the labeling pigment, and the (F layer) color adjusting layer (I) can be constituted in this order.

Still another gist of the resin deterioration detecting material of the present invention is that at least (A layer) a deterioration adjusting layer which deteriorates in conjunction with deterioration of the detected resin molded article, and (C layer) a detected resin molded article. A color-changing layer containing a fading pigment and a resin degradation accelerator in a matrix of the same material as (G layer)
The color adjusting layer (II), the (E layer) labeling layer protective layer (D layer), the labeling layer containing the labeling pigment, and the (F layer) color adjusting layer (I) can be constituted in this order.

Further, the deterioration adjusting layer may contain a resin deterioration adjusting agent in a matrix of the same material as the resin molded article to be detected.

Further, the color-changing pigment or the fading pigment may be an organic pigment, and may be an azo pigment or a phthalocyanine pigment. In particular, C.I.
I. Pigment Red.

The label pigment may be a fluorescent pigment or a photochromic material.

Further, the resin deterioration regulator may be a stabilizer.

[0022] The labeling layer protective layer may contain a stabilizer.

Further, the resin deterioration detecting material of the present invention may be a film having a thickness of at least 10 μm or more.

Furthermore, the resin molded article to be detected may be made of a thermoplastic resin, and may be an olefin resin. In particular, the olefin resin may be a polyethylene resin or a polypropylene resin.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the resin deterioration detecting material of the present invention will be described in detail.

The resin deterioration detecting material of the present invention is used attached to a resin molded body for the purpose of detecting deterioration of the resin molded body and notifying an appropriate time for replacement. As the detection target resin which is a material of the resin molded body to which the resin deterioration detection material of the present invention can be applied, any thermoplastic resin can be used, for example, an olefin resin, a polystyrene resin,
Polyamide-based resins and the like can be mentioned. In particular, it can be suitably used for polyolefin-based resins that are increasing in demand as described above, for example, polyethylene, polypropylene, polybutadiene, and the like. Deterioration of the polyolefin resin is caused by generation of radicals by heat and light and oxidation by oxygen. When the polymer material is degraded and a crack is generated on the surface, oxygen penetrates from the surface and the deterioration proceeds.

The resin deterioration detecting material 10 of the present invention is basically a laminated structure composed of a combination of a deterioration adjusting layer (A layer) 12 and a color change layer (B layer) 14 as shown in FIG. Body. The deterioration adjustment layer (A layer) 12 is a layer that deteriorates in conjunction with the deterioration of the detected resin molded body 16, and rapidly deteriorates at the time of detecting the deterioration of the detected resin molded body 16, such as oxygen,
By transmitting the ultraviolet rays, the lower color change layer (B
The layer 14 has the purpose of introducing oxygen or ultraviolet rays. Further, the color change layer (B layer) 14 contains a pigment and a resin deterioration accelerator, and when oxygen and ultraviolet light arrive, the deterioration is promoted and the pigment, the ultraviolet light and oxygen react to rapidly change the color. The purpose is to visually identify the detection time.

The deterioration adjusting layer (A layer) 12 will be described. The deterioration adjusting layer (A layer) 12 covers the color change layer and is on the uppermost layer of the resin deterioration detecting material 10 of the present invention, and is directly affected by the environment in which the detected resin molded body 16 is used, and Degrades in conjunction with the deterioration of the detected resin molded body 16 so as to serve as an index of the deterioration of the detected resin molded body 16 due to the influence of. The deterioration adjusting layer (A layer) 12 allows oxygen and ultraviolet rays to be introduced from the external environment due to deterioration, and the color change layer (B layer)
The purpose is to adjust the timing at which oxygen or ultraviolet rays reach 14 in accordance with the deterioration timing of the resin molding 16 to be detected. The replacement time of the detected resin molded body 16 is determined according to the detected resin molded body 16.
The rate of deterioration depends on the material used, and the same material may differ depending on the purpose of use of the resin molding 16 to be detected. Therefore, the deterioration detection timing can be adjusted by the thickness of the deterioration adjusting layer (A layer) 12, the type of the added substance, and the added amount in conformity with these various requirements.

The resin as the matrix of the deterioration adjusting layer (A layer) 12 is basically the same material as the resin molded article 16 to be detected. Therefore, when the resin molding 16 to be detected has various fillers added to the polymer material, the same material to which the fillers are added becomes a matrix.
Due to the requirement that the resin molded article 16 to be detected be used for as long a life as possible while maintaining the physical properties that can withstand the application, it is adjusted so that it deteriorates slightly earlier than the physical property deterioration due to the deterioration of the resin molded article 16 to be detected. Is done.

From the knowledge of the relationship between the film thickness and the degree of deterioration, the film thickness of the deterioration adjusting layer can be determined. FIG.
3 shows the absorbance of carbonyl groups in the thickness direction of an air-cooled LDPE (low density polyethylene) film aged for a day. In addition, light irradiation uses 300 Sunshine Long Life Weather Meter WEL-300LH (manufactured by Suga Test Instruments Co., Ltd.), and carbon is Toshiba Corporation Sunshine Ultra Long Life Carbon SLEM-V, SLE.
-L, black panel temperature 63 ° C, humidity 60
%, Irradiation time was 12 days. Note that the conditions of this light irradiation are such that 1000 hours of irradiation corresponds to one year of ultraviolet irradiation in Japan. The measurement of the absorbance of the carbonyl group was performed by cutting a 108 μm-thick LDPE film irradiated with light for 12 days into a predetermined width using a microtome, and using a micro FTIR to measure the thickness from the film surface to 25 μm in the thickness direction.
Every time, the measurement was sequentially performed in a range of 50 μm × 21 μm × 108 μm.

As a result, it can be seen that a marked difference appears in the amount of carbonyl groups formed between the surface portion and the inside. In particular, the amount of the carbonyl group rapidly decreases toward the center.
In other words, a large amount of oxygen is consumed in the surface layer, indicating that the diffusion of oxygen into the sample is small. In the central part (about 0.5 mm from the surface), about one third of the surface has an oxygen permeability. It is suggested to be an amount.

Therefore, as described above, the film thickness of the polymer material and the degree of deterioration of the resin used for the resin molded article to be detected are qualitatively determined, and the deterioration rate is determined by the thickness based on the data. Can be adjusted. This layer whose thickness has been adjusted is used as a deterioration adjusting layer (A layer) 12 of the resin deterioration detecting material 10 of the present invention.
As a result, it is possible to adjust the time when oxygen reaches the color change layer (B layer) 14 which is the lower layer, and it is possible to adjust the detection time of resin deterioration.

The deterioration adjustment is performed by the deterioration adjustment layer (A layer) 1.
It can also be carried out by adding a resin deterioration regulator to the matrix of No. 2. As the resin deterioration adjusting agent, a stabilizer is used to suppress deterioration due to heat or light. Stabilizers participate at any stage of the degradation reaction and inhibit its progress.

Deterioration is caused by the generation of radicals under the influence of heat, ultraviolet rays, metal ions, and the like, and progresses rapidly by a chain reaction (auto-oxidation reaction) with oxygen in the air. Stabilizers for removing this radical generation factor include metal deactivators, ultraviolet absorbers, radical chain initiation inhibitors such as quencher, HALS (hindered amine light stabilizer), phenolic antioxidants, and amine based Hydroperoxide decomposers that prevent radical cleavage of hydroperoxides, such as radical scavengers such as antioxidants, sulfur-based antioxidants, and phosphorus-based antioxidants, are effective.

The quencher has a function of quenching the excited energy, and examples thereof include organic nickel compounds. The ultraviolet absorber has a function of absorbing ultraviolet light, and includes, for example, benzotriazole and benzophenone. The phenolic antioxidant has a function of stopping hydrogen radical reaction by donating hydrogen and becoming a stable phenoxy radical by itself, and includes a hindered phenol compound and a semi-hindered phenol compound. HALS is
It has a function of trapping a radical generated by light without absorbing ultraviolet rays, and includes a hindered amine compound. Sulfur-based antioxidants have a function of detoxifying hydroperoxides, and include thioether-based compounds. Phosphorus antioxidants have a trivalent phosphorus atom of ROOH
Has a function of stabilizing by pulling out oxygen atoms from itself, and includes phosphite compounds and phosphonite compounds. These may be used alone or in combination of two or more, and may be selected depending on the degree of their effect.

The deterioration control layer (A layer) 12 of these stabilizers
The amount added to the resin is adjusted in relation to the amount of the stabilizer previously added to the matrix of the resin molded article to be detected and the film thickness. If the amount of the stabilizer added is smaller than the amount of the stabilizer added to the matrix of the detected resin molded product, it deteriorates faster than the detected resin molded product. Further, since the amount of the stabilizer added and the amount of ultraviolet absorption are correlated, the deterioration time can be adjusted by the amount of the stabilizer. FIG. 4 shows that the matrix is HDPE (high-density polyethylene) and H
1.0% by weight of the amount of ALS added to the amount of HDPE,
FIG. 6 is a graph showing a comparison of changes in residual tensile elongation due to exposure to Florida at 0.5% by weight and at 0.5% by weight (Source: CMJ, Inc., supervised by Zenjiro Osawa, "Longer Life of Polymer Materials and Environmental Measures" Page 25, Figure 2.6
Change in tensile elongation after HDPE exposure to Florida). This indicates that the higher the stabilizer content, the more the mechanical strength can be maintained. In addition, the comparative example which does not add a stabilizer is shown. The measurement was based on JIS K7113.

Next, the color change layer (B layer) 14 contains a deterioration accelerator and a pigment whose color changes in a matrix. As the matrix, basically, the same material as that of the resin molded article 16 to be detected is preferable. When a polymer material other than the resin molding 16 to be detected is used, it is a material that does not react with the material of the upper deterioration control layer (A layer). Can be variously selected as long as the material is rapidly deteriorated in synergy with the action of the deterioration accelerator.

Deterioration of the deterioration adjusting layer (layer A) 12 progresses to generate cracks. The fine cracks cause the color change layer (layer B).
When oxygen permeates up to 14, this oxygen permeation
It is necessary that the color change layer rapidly deteriorates, and the contained pigment reacts to ultraviolet rays and oxygen to rapidly change the color. For this reason, a deterioration accelerator is added to the matrix of the color change layer (B layer) 14. In the context of pigments that change color, the selection of a degradation accelerator is important. When the reaction of the pigment that changes color with ultraviolet light or oxygen is not abrupt, adjustment such as adding a large amount of a deterioration accelerator is necessary.

Examples of the deterioration accelerator include a radical generator, a metal compound, a photosensitizer and the like. They have the function of cutting the main chain of the polymer constituting the matrix and rapidly increasing the oxygen permeation rate, thereby causing a dramatic color change and adding a deterioration detection function.

More specifically, some radical generators are used as radical polymerization initiators when polymerizing polymers. For example, AMVN (2,2'-azobis (2,4-dimethylvaleroni
trile)), AAPH (2,2'-azobis (2,4-aminopropane) dihydro
chloride), AIBN (2,2'-azobis (4-methoxy-2,4-dimethy
l valeronitrile), AMBN (2,2'-azobis-2-methylbutyron
itrile), ADVN (2,2'-azobis-2,4-dimethyl valeronitri
le), ACHN (1,1'-azobis-1-cyclohexane carbonitrile),
Examples include azo compounds such as MAIB (dimethyl-2,2'-azobis-4-cyanovaleric acid) and organic peroxides such as BPO (benzoyl peroxide). Further, by introducing a carbonyl group into the polymer constituting the matrix by copolymerization, it functions to promote the autoxidation reaction.

The metal compound has a function of promoting the photodegradation of the polymer by generating a radical by photodecomposition of the metal complex.
In addition, even if light does not continuously flow due to the presence of metal ions, deterioration proceeds. For example, dithiocarbamate complex (Fe), salicylaldehyde complex (Co, Cu, M
n, Fe), an acetylacetone complex (Fe, Co), and the like. Further, when a substituted benzophenone is used in combination with a Ti or Zr complex, deterioration can be accelerated.

The photosensitizer is effective for photodecomposition of a polymer, and examples thereof include aromatic ketone derivatives such as benzophenone, acetophenone and anthraquinone. The photoexcited benzophenones extract hydrogen from the polymer and start photo-oxidation, thereby acting to promote deterioration.

As such a deterioration accelerator, specifically,
Is Iron (III) Acetylacetatonate Class 1 (Fe (CH₃CO
CHCOCH₃)₃FW = 353.17)
Cobalt (III) Acetylacetatonate1
Grade (Co (CH₃COCHCOCH ₃)₃FW = 35
6.26) (Katayama Chemical Industry Co., Ltd.).
The content of the deterioration accelerator is based on the total amount of the matrix of the color change layer.
On the other hand, for example, in the case of Iron (III) Acetylacetatonate,
0.3% to 1% by weight, Cobalt (III) Acetylacetatona
In the case of te, the content is preferably 0.04% by weight to 1% by weight.

Next, as the pigment contained in the color changing layer (B layer) 14, those whose molecular structure is changed by the introduction of ultraviolet rays and oxygen, or whose color is clearly changed by isomerization of steric configuration, or Various types are used within the range of fading. Such a pigment is preferably an organic pigment.
More specifically, a double bond contained in the structure of the pigment is broken by ultraviolet rays to generate a radical, and the radical is bonded to oxygen to cleave the bond to change the molecular structure, such as a phthalocyanine pigment or an azo pigment. Among organic pigments. For example, cyanine blue 4920, which is an organic pigment for plastic manufactured by Dainichi Seika Kogyo Co., Ltd.
(Blue), cyanine green 2G0 (green), A110 red (red), Seika First Yellow 2200 (yellow). An azobenzene-based dye is exemplified as a pigment whose color changes due to isomerization of the configuration. The content of the pigment that changes color is preferably 0.5% by weight to 2% by weight based on the total amount of the matrix of the color change layer.

The pigment contained in the color change layer (B layer) 14 detects the deterioration time of the resin molded body 16 to be detected by a distinct color change and the color after the change. Or
Due to the fading, the color of the resin molded body 16 to be detected itself appears through the faded color change layer (B layer) 14 to detect the deterioration of the resin.

As another embodiment of the resin deterioration detecting material of the present invention, as shown in FIG. 5, an embodiment 18 in which the color change layer and the deterioration adjusting layer are the same layer is also possible. More specifically, it is possible to prevent the matrix from being deteriorated as a one-layer structure containing a pigment that changes color and a resin deterioration adjuster in a matrix of the same material as the resin to be detected. When the radical stabilizer loses its ability to trap radicals, the degradation of the matrix progresses rapidly, causing cracks to permeate oxygen and at the same time permeate ultraviolet light. When ultraviolet light and oxygen are transmitted, the pigment becomes ultraviolet light,
It reacts with oxygen and changes color. Therefore,
The deterioration time of the matrix can be adjusted according to the deterioration time of the resin molded article to be detected by the resin deterioration adjusting agent in the matrix.

Further, as another embodiment 20 of the resin deterioration detecting material of the present invention, as shown in FIG. 6, a color change layer (referred to as a C layer) 22 using a fading pigment is provided below.
There is an embodiment in which a sign layer (D layer) 24 is provided. Example 20 including a color change layer (C layer) 22 using a fading pigment
It is preferable that a color different from the color of the resin molded body 16 to be detected is developed because it is easy to visually detect. Marking layer (D
The layer (D) 24 is a marker layer (D) that appears through the color change layer (C layer) 22 as the pigment of the color change layer (C layer) 22, which is the upper layer, fades due to the reaction with oxygen. The layer 24 has a role of detecting the deterioration time of the resin molded article 16 to be detected by the color of the pigment of the pigment.

The pigment that can be contained in the marker layer (D layer) 24 is not particularly limited as long as it is stable without being discolored by light irradiation until the detection time, and various inorganic pigments and organic pigments can be used. May be selected. Particularly, a fluorescent pigment or a photochromic material is used. As the fluorescent pigment, ZnS: Ag, Al, Zn ₂ SiO ₄ : M
Pigments containing a phosphor powder that emits electroluminescence such as n ²⁺ or Y ₂ O ₂ : Eu ³⁺ are exemplified. Examples of the photochromic material include an azo-based material, a liquid crystal material, a polarizing material, and photo-induced color change. Metal amorphous material. For example, fulgide, diarylethene, norbornadiene, spiropyran, triallylmethane, stilbene, azobenzene, thioindigo,
Salicylideneaniline, dihydroxyanthraquinone and the like. When such a material is used, when it is difficult to observe the color of the marker layer (D layer) 24 in the vicinity during the application process to a product, light (for example, a flashlight or the like) is irradiated from a distance to emit fluorescence. If color development is possible, it is possible to clearly find the deteriorated part.

The matrix of the marker layer (D layer) 24 is basically made of the same material as the resin molded product to be detected, but may be another polymer material which is stable to light irradiation. When the matrix is a polymer material that is unstable to light irradiation including the resin molded product to be detected, a stabilizer is contained in the label layer (D layer) 24, and the label layer (D layer) 24 is deteriorated by light irradiation. It is preferable to prevent this. Alternatively, an embodiment 2 shown in FIG.
As in 6, the marker layer (D layer) 24 and the color change layer (C layer)
Between the layers 22, a layer containing a stabilizer (E layer) may be laminated as a protective layer 28 of the label layer (D layer) 24. As the stabilizer, the substances described above can be used.

As yet another example of the embodiment of the resin deterioration detecting material of the present invention, as shown in FIG. 8, a marker is used to prevent the material from being affected by the color of the resin molded article to be detected. A mode in which the color adjustment layer (I) (F layer) 32 is laminated below the layer (D layer) 24 and adjacent to the surface of the detected resin molded body 16 when used for the detected resin molded body 16. There are 30. The color adjustment layers (I) and (F layer) 32 include
The label layer (D layer) 2 offsets the color of the resin molding 16 to be detected.
And a pigment for preventing the color of No. 4 from mixing with the color of the resin molding 16 to be detected. The pigment is not particularly limited as long as it is a material that is stable without being discolored by light irradiation, and various inorganic pigments and organic pigments can be selected. For that purpose, an opaque layer containing a white pigment is preferable. Also,
The matrix of the color adjustment layers (I) and (F layer) 32 is basically the same material as the resin molding 16 to be detected, but may be another polymer material stable to light irradiation. In the case of a polymer material which is unstable to light irradiation including the resin molded body 16 to be detected, a stabilizer is contained in the marker layer (D layer) 24, and the color change layer (C layer) 22 is deteriorated by light irradiation. Is preferably prevented.

Further, as still another example 34 of the embodiment of the resin deterioration detecting material of the present invention, as shown in FIG. 9, the color of the color change layer (C layer) 22 is clarified. The color of the marker layer (D layer) 24 is changed to the color change layer (C layer) 22.
Between the marker layer (D layer) 24 and the color change layer (C layer) 22 so as not to affect the color adjustment layer (II) (F layer) 3.
6, the color of the marker layer (D layer) 24 may be reduced. It is preferable to add an opaque pigment which is easily faded to the color adjusting layer (II) (G layer) 36. A light organic pigment or a dilute white inorganic pigment is used, and a deterioration accelerator is added to the matrix to form a layer. Constitute. Preferable pigments for this layer include, specifically, Seika First Yellow 2200 (yellow) and Seika First Yellow 2600, which are organic pigments for plastic manufactured by Dainichi Seika Kogyo Co., Ltd.
(Yellow) and titanium dioxide (white) manufactured by DuPont Japan Limited.

As shown in FIG. 10, the resin deterioration detecting material of the present invention comprises a deterioration adjusting layer (A layer) 12 and a color change layer (C
Layer) 22, labeling layer (D layer) 24, labeling layer (D layer) 2
4, a color adjustment layer (I) (F layer) 32 and a marker layer (D
There is also an embodiment 38 in which a color adjustment layer (II) (G layer) 36 is laminated between the layer 24 and the color change layer (C layer) 22.

Further, the resin deterioration preventing material of the present invention comprises:
As shown in FIG. 11, in addition to the deterioration adjustment layer (A layer) 12, the color change layer (C layer) 22, and the marker layer (D layer) 24, a color adjustment layer (I) is formed below the marker layer (D layer) 24. ) (F layer) 32,
A labeling layer protective layer (E layer) 28 on a labeling layer (D layer) 24;
Below the color change layer (C layer), a color adjustment layer (II) (G
There is also an embodiment 40 in which the layers 36 are stacked.

The various aspects of the resin deterioration detecting material of the present invention described above can be selected in relation to the selected pigment and the like.

As described above, the resin deterioration detecting material of the present invention is preferably in the form of a film.
The thickness and required strength of various resin molded articles to be detected, such as pipes, wires, general molded articles such as boxes and cases, to which the resin deterioration detection material of the present invention is applied (for example, in a polyethylene pipe for gas, According to JIS K6774, a tensile strength of 180 kg / cm ² or more, and a polyethylene pipe for water distribution has a tensile yield strength of 2 according to PWA 001.
0.0 MPa (204 kgf / cm ² or more) is required. Can be selected variously depending on the relationship with
m or more.

As a method for using the resin deterioration detecting material of the present invention, the resin deterioration detecting material is used by attaching it to a resin molding to be detected. In this case, the deterioration adjustment layer (layer A) of the resin deterioration detection material of the present invention, which is a laminate of the above layers, is set to the side directly in contact with the environment in which the resin molding to be detected is installed, and the lowermost layer is the resin to be detected. Attached as molded body side. Adhesion methods include adhesion,
It can be carried out by a known technique such as crimping. In the case of bonding, bonding may be performed with an adhesive or as a laminate in which an adhesive layer is further laminated as the lowermost layer on the side of the resin molded product to be detected.

For example, in the molding step of the resin molded article to be detected, it can be added as a part of the surface layer of the resin molded article to be detected. For example, when forming a tubular article for gas or water pipes, the material is melt-kneaded and then extruded into a tubular shape. Separately manufactured, while the resin deterioration detection material of the present invention in the form of a film of a certain width is unwound, along with the extruded and discharged tubular material, it is passed through a thermocompression roll to form a surface of the tubular material. The resin deterioration detection material of the present invention can be installed.

Alternatively, the resin deterioration detecting material of the present invention, which is provided with an adhesive layer as a lower layer, is commercialized as a film having a desired width, and cut out and adhered to a required portion of the resin molded body to be detected in a required length. There is also a mode in which the product is attached to a release paper in the form of a seal having various shapes and is attached to the resin molded article to be detected as necessary.

Furthermore, there is also a method of embedding the resin deterioration detecting material of the present invention in a resin molded article to be detected. For the embedding, the installation position may be formed in the concave portion of the resin molded product to be detected in advance, or an embedding process may be added to the molding process of the molded product. The depth of embedding can be selected according to the required mechanical strength of the resin molding to be detected.

As described above, the resin deterioration detecting material of the present invention makes it possible to detect the deterioration of the resin molding to be detected in advance. As mentioned above, although one example of the embodiment of the resin deterioration detection material according to the present invention has been described, the present invention
The present invention is not limited to only these embodiments. For example, when a film is used in which a plurality of types of films having different detection times are combined, if the film is installed on a resin product which is a detection target, the detection target may be changed depending on the detection timing. It is also possible to know the degree of deterioration in a stepwise manner. Thus, the present invention provides
Various improvements, changes, and modifications can be made based on the knowledge of those skilled in the art without departing from the spirit of the invention.

[0061]

EXAMPLES The following examples using the resin detecting material according to the present invention will be described. The invention is not limited to these examples.

[0062]

[Preliminary Test 1] Four types of organic pigments, cyanine blue 4920, cyanine green 2G0, A110 red, and Seika First Yellow 2200, were used, and the light resistance of these pigments was confirmed.

LDPE pellets (SCIENTIFIC POLYMER P
RODUCTS.INC made Mw = 50,000) 1w for 100g
t% of the above pigment is added, and a mixing mixer R100H
The mixture was kneaded at 170 ° C. for 10 minutes (manufactured by Toyo Seiki Seisaku-sho, Ltd.), cooled naturally, and then pulverized by a pulverizer UGC-280KGS (produced by Horai Co., Ltd.). Under the same conditions as the film forming conditions of the LDPE alone, L
DPE powder was formed into two types of films having a thickness of 0.5 mm and 50 μm. Molding was performed using a hot press (manufactured by Techno Supply Co .; maximum output: 700 kgf / cm ² ), using a 0.485 mm aluminum plate and a 15 μm aluminum foil as a mold, and PET film (the surface of which was sufficiently washed with ethanol). Manufactured by Toray Industries, Inc .; 75 μm
Thickness) with LDPE pellets in between, pressure 100kg
The film was pressed under conditions of f / cm ² , a temperature of 150 ° C., a residual heat of 2 minutes and a press of 3 minutes to form a film. Then, it was quenched in ice water. These films were applied to cyanine blue 4
920 was added to film (B), and cyanine green 2G0 was used to film (G), A110
A film using red is referred to as a film (R), a film using cyanine blue 4920 is referred to as a film (B), and a film using Seika First Yellow 2200 is referred to as a film (Y).

The obtained LDPE film containing a pigment was coated with a xenon long life weather meter SC250.
-W (manufactured by Suga Test Instruments Co., Ltd.) using a 2.5 kW Xe lamp and a black panel temperature of 63 ° C. and a humidity of 50%
Irradiation was performed under the following conditions. The irradiation time and irradiation energy are
It is as shown in the table below.

[0065]

[Table 1]

A preliminary test was conducted by irradiating a Xe lamp for 35 days, and the degree of fading was examined. FIG. 12 shows changes in absorbance of carbonyl groups of various films irradiated with a Xe lamp.

To quantify the degree of fading due to deterioration,
FIG. 13 shows the measurement result of the color difference change rate. Each pigment exhibited a characteristic fading tendency.

In the film (R), a color difference rapidly occurred shortly after the light irradiation, and after 20 days, the value was almost constant in a transparent state. On the other hand, the film (Y) shows a tendency to fade gradually with light irradiation, and the films (B) and (G)
Almost unchanged until the 14th. This period is a fading induction period. The color rapidly changed over the 20th day, after which the color fading tended to stop.

The above preliminary experiment 1 showed that the fading induction period differs depending on the type of the pigment. Therefore, it is suggested that the selection of the pigment can adjust the deterioration time by using the pigment together with the deterioration accelerator.

[0070]

[Preliminary experiment 2] Xe light irradiation was performed on a non-added LDPE film, and the degree of deterioration was measured. As a deterioration index, a change in absorbance of a carbonyl group, a change in breaking stress and a change in breaking strain by a tensile test were measured.

The absorbance of the carbonyl group was measured using a micro Fourier transform infrared spectrometer FTIR-8300 (manufactured by Shimadzu Corporation; measurement wave number range: 350 to 7800 cm).
^-1 ) was measured by a transmission method.
The evaluation was made based on the absorbance of the stretching vibration of the carbonyl group appearing near 0 cm ⁻¹ . The absorbance Ao is obtained by measuring the thickness of the sample by d.
(Mm), Baseline transmittance Io, 1715 cm
The permeability of ^-1 when the _{I 17 15,} was determined by equation (1). The unit is mm ⁻¹ .

[0072]

(Equation 1)

The rate of change in color difference was determined by measuring the rate of change in color of a standard white plate using an optical spectroanalyzer SZ- # 80 colorimeter (manufactured by Nippon Denshoku Industries Co., Ltd.).

The mechanical strength was measured using a universal tensile tester 5
Using a type 569 (manufactured by Inston Japan Co., Ltd.), a stress-strain test (rupture stress) is performed in accordance with JIS K7113 (a tensile test method for plastics) and JIS K 7127 (a tensile test method for plastic films and sheets). , Breaking strain). Humidity 23 ±
Test speed 20 in a constant temperature / humidity room at 2 ° C and relative humidity 50 ± 2%
mm / min. The sample was a micro dumbbell type test piece shown in FIG. FIG. 15 shows the results. Light irradiation was performed for 28 days.

From the results, it can be seen that the Xe light irradiation time up to about 6 days is the deterioration induction period, and after that, the carbonyl group absorbance rapidly increases. As a result, the breaking stress and the breaking strain are greatly reduced. Therefore, it was found that the physical property reduction criterion that required deterioration detection was about 6 to 9 days.

[0076]

[Example] Hot press (manufactured by Techno Supply Corporation;
Maximum output: 700 kgf / cm ² ) and 0.485
PET using aluminum plate of 15 mm and aluminum foil of 15 μm for the mold, the surface of which is sufficiently washed with ethanol.
The LDPE pellets were sandwiched between films (manufactured by Toray Industries, Inc .; 75 μm thick), formed into a film under the conditions of a pressure of 100 kgf / cm ² , a temperature of 150 ° C., a residual heat of 2 minutes and a press of 3 minutes, and were pressed. Thereafter, the film was rapidly cooled in ice water to produce a 50 μm-thick LDPE-only film.

1 wt./100 g of LDPE pellets
% Of A110 Red (trade name; manufactured by Dainichi Seika Kogyo Co., Ltd.), kneaded with a kneading mixer R100H (manufactured by Toyo Seiki Seisaku-sho, Ltd.) at 170 ° C. for 10 minutes, and after natural cooling, a crusher UGC- It was pulverized by 280KGS (manufactured by Horai Co., Ltd.). Under the same conditions as those for forming the LDPE-only film, the pigment-added LDPE powder was formed into a 50 μm-thick film.

A film containing only LDPE was laminated on a film to which a pigment was added to obtain a film-like resin deterioration detecting material of the present invention. Laminating conditions are hot press (Techno Supply Co., Ltd .: Maximum output: 700 kgf)
/ Cm ² ) and a 0.485 mm aluminum plate was used for the mold. PE whose surface has been thoroughly washed with ethanol
A 50 μm film of each layer constituting the T film was overlaid. Pressure 50 kgf / cm ² , temperature 140
The film was formed at a temperature of 1 ° C. for 1 minute with a residual heat and a press for 1 minute, and pressed. Then, quench in ice water, and add
mm.

The obtained film-like resin deterioration detecting material was used as a xenon long life weather meter SC250-
W (manufactured by Suga Test Instruments Co., Ltd.)
Irradiation was performed for 9 days using an e-lamp at a black panel temperature of 63 ° C. and a humidity of 50%, and the color change was observed. The irradiation time and irradiation energy are as shown in the table below.

[0080]

[Table 2]

The red color of the laminated film started to fade from 6 days after Xe light irradiation, and became completely colorless from red after 9 days.

FIG. 15 shows that the deterioration of LDPE, which is the material of the resin molded article to be detected assumed in this embodiment, rapidly progresses after 10 days. As for the film which is a resin deterioration detecting material which completely discolors, the detection indicating the time immediately before the deterioration was proved.

[0083]

According to the resin deterioration detecting material of the present invention, the deterioration time of a resin molded article can be determined, and when used for a structural material, the replacement time due to deterioration can be clarified, thereby preventing a deterioration accident. Can be. Therefore, if there is no functional problem, the material can be used for as long as possible, the life of the material can be extended, and resource saving can be achieved. By using the resin deterioration detection material of the present invention, the reliability of the polyolefin-based plastic having a low environmental load is improved, it is environmentally friendly, can be used safely and has a long life, and the added value can be increased to a general-purpose plastic. . Eventually, the reliability of the information and communication infrastructure can be improved, the information and communication society can be promoted, and a society where people can live with peace of mind can be constructed.

[Brief description of the drawings]

FIG. 1 illustrates the mechanism of resin degradation of polyolefin.

FIG. 2 is a tenth embodiment of the resin deterioration detecting material of the present invention.

FIG. 3 shows an air-cooled LDPE aged for 12 days.
It is a graph which shows the light absorbency of the carbonyl group with respect to the thickness direction of a (low density polyethylene) film.

FIG. 4 is a graph showing a change in residual tensile elongation due to exposure of HDPE to Florida.

FIG. 5 shows another embodiment 18 of the resin deterioration detecting material of the present invention.

FIG. 6 shows still another embodiment 20 of the resin deterioration detecting material of the present invention.

FIG. 7 shows still another embodiment 26 of the resin deterioration detecting material of the present invention.

FIG. 8 shows still another embodiment 30 of the resin deterioration detecting material of the present invention.

FIG. 9 shows still another example 34 of the resin deterioration detecting material of the present invention.

FIG. 10 shows still another embodiment 38 of the resin deterioration detecting material of the present invention.

FIG. 11 shows a further embodiment 40 of the resin deterioration detecting material of the present invention.

FIG. 12 is a graph showing changes in absorbance of carbonyl groups of various films irradiated with a Xe lamp.

FIG. 13 is a graph showing a standard white plate color difference change rate of an LDPE film containing a pigment with respect to a light irradiation time.

FIG. 14 is a schematic view of a microdumbbell-type test piece.

FIG. 15 is a graph showing the results obtained by adding X to an LDPE film without additives.
7e is a graph showing changes in irradiation time and deterioration index.

[Explanation of symbols]

10, 18, 20, 26, 30, 34, 38, 40; Examples of the resin deterioration detection material of the present invention 12; deterioration adjustment layer (A layer) 14; color change layer (B layer) 16; Body 22; Color changing layer using discolored pigment (C layer) 24; Labeling layer (D layer) 28; Protective layer (E layer) of labeling layer (D layer) 32; Color adjusting layer (I) (F layer) 36; color adjustment layer (II) (G layer)

Claims (20)

[The claims] 1. A resin deterioration detecting material comprising at least a layer containing a pigment whose color changes and a resin deterioration adjusting agent in a matrix of the same material as the resin molded product to be detected. 2. A pigment whose color changes in at least a (A layer) deterioration adjustment layer which deteriorates in conjunction with the deterioration of the detected resin molded article, and (B layer) a matrix of the same material as the detected resin molded article. And a color change layer containing a resin deterioration accelerator,
A resin deterioration detection material composed of 3. The resin deterioration detection material according to claim 1, wherein the color-changing pigment is a fading pigment. 4. A pigment whose color fades at least in a matrix of the same material as the (A layer) a resin molded article to be detected, and a deterioration adjusting layer that deteriorates in conjunction with the deterioration of the (A layer) resin molded article to be detected. And a color change layer containing a resin deterioration accelerator,
(D layer) A resin degradation detection material composed of a marker layer containing a marker pigment in this order. 5. A pigment and a resin which discolor in a matrix of the same material as at least a (A layer) deterioration adjustment layer which deteriorates in conjunction with the deterioration of the resin molding to be detected, and (C layer). A color change layer containing a deterioration accelerator, (E
Layer) labeling layer protective layer (D layer) labeling layer containing labeling pigment,
A resin deterioration detection material composed in the following order. 6. A pigment and a resin which are discolored in at least a (A layer) deterioration adjusting layer which deteriorates in conjunction with the deterioration of the resin molding to be detected and (C layer) a matrix of the same material as the resin molding to be detected. A color change layer containing a deterioration accelerator, (D
Layer) A resin deterioration detecting material composed of a label layer containing a label pigment and a (F layer) color adjustment layer (I) in this order. 7. At least (A layer) a deterioration adjusting layer that deteriorates in conjunction with deterioration of a resin molded body to be detected, and (C layer) a pigment and a resin that fade in a matrix of the same material as the resin molded body to be detected. A color change layer containing a deterioration accelerator, (G
A layer) a color adjustment layer (II) and (D layer) a marker layer containing a marker pigment. 8. A pigment and a resin which fade in a matrix of the same material as at least a deterioration adjusting layer which deteriorates in conjunction with the deterioration of the resin molded body (A layer) and a resin molded body (C layer). A color change layer containing a deterioration accelerator, (G
Layer) a color adjusting layer (II), a (D layer) a labeling layer containing a labeling pigment, and (F layer) a color adjusting layer (I).
Resin deterioration detection material. 9. At least (A layer) a deterioration adjusting layer that deteriorates in conjunction with deterioration of a resin molded article to be detected, and (C layer) a pigment and a resin that fade in a matrix of the same material as the resin molded article to be detected. A color change layer containing a deterioration accelerator, (G
Layer) color adjustment layer (II), (E layer) marker layer protective layer (D
Layer) A resin deterioration detecting material comprising a labeling pigment-containing labeling layer and an (F layer) color adjusting layer (I) in this order. 10. The deterioration adjusting layer contains a resin deterioration adjusting agent in a matrix of the same material as the resin molded body to be detected.
The resin deterioration detecting material according to claim 2. 11. The pigment according to claim 1, wherein the color changing pigment or the color fading pigment is an organic pigment.
The resin deterioration detection material according to any one of the above. 12. The resin deterioration detecting material according to claim 11, wherein the organic pigment is an azo pigment or a phthalocyanine pigment. 13. The method according to claim 13, wherein the organic pigment is C.I. I. 13. The resin deterioration detecting material according to claim 12, comprising Pigment Red. 14. The resin deterioration detecting material according to claim 4, wherein the marker pigment is a fluorescent pigment or a photochromic material. 15. The resin deterioration detecting material according to claim 10, wherein the resin deterioration adjusting agent is a stabilizer. 16. The resin deterioration detecting material according to claim 5, wherein the marker layer protective layer contains a stabilizer. 17. The resin deterioration detecting material according to claim 1, which is a film having a thickness of at least 10 μm or more. 18. The resin deterioration detecting material according to claim 1, wherein the resin molded body to be detected is made of a thermoplastic resin. 19. The resin deterioration detecting material according to claim 18, wherein the thermoplastic resin is an olefin resin. 20. The resin deterioration detection material according to claim 19, wherein the olefin resin is a polyethylene resin or a polypropylene resin.