JPS60185823A - Method for reclaiming waste carpet - Google Patents

Abstract

PURPOSE:To make it possible to mix a large amount of waste carpet in a felt and reutilize effectively the waste carpet, by mixing a pulverized waste carpet with a urethane prepolymer, pulverizing the resultant mixture, and using the formed powder as a raw material for the felt. CONSTITUTION:A waste carpet, e.g. trimmed waste, of an automotive carpet is pulverized to give 0.3-30mm. size, and 100pts.wt. resultant pulverized material is sprinkled with 3-30pts.wt. urethane prepolymer and stirred. The resultant mixture is then pulverized before complete curing of the prepolymer to given an aggregate of fibers and urethane having 3-10mm. size, which is then used as a raw material for a felt, inserted into an interlayer of miscellaneous fiber webs and bonded with a thermosetting binder, etc. to form the aimed felt.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to recycling treatment of carpet waste. In particular, the present invention relates to the recycling of industrial waste such as trimming waste generated from the manufacturing process of automobile carpets, which are laid on automobile floors, decks, etc.

Plants that manufacture automotive floor carpets generate a large amount of carpet debris such as trimming debris every day.

Carpets for automobiles are generally made of fibers such as polypropylene, polyamide, polyester, etc., and are lined with a thermoplastic synthetic resin such as low-density polyethylene resin or EVA resin to maintain the shape of the carpet. This backing layer usually contains a chlorine-based resin, such as vinyl chloride resin, to make the carpet flame retardant. Since automobile floors and decks generally have complex shapes and contours, a large amount of debris is generated when carpets are trimmed to fit.

Reusing these scraps met the following problems in the past. In other words, ■The fibers that make up car vents are thicker and shorter than normal fibers, so they are less likely to get tangled when made into felt, so even if they are mixed into felt, at most 1
Only about 5% can be mixed in.

■It was considered to mix it with low-density polyethylene when lining the carpet, but this also caused the chlorine-based resin contained in the backing layer of the scraps to decompose and cause processing machines such as extruders and T-dies to There have been problems in that the inner surface is corroded or clogged, or the backing layer foams and its physical properties deteriorate.

The present invention is characterized by providing a carpet recycling method that does not have the above-mentioned problems. In particular, it improves the lack of entanglement when carpet waste is used as a raw material for felt, and makes it possible to mix a large amount of carpet waste into felt. The purpose is to

The gist of the present invention is a carpet waste recycling method comprising the following steps.

(1) Pulverize or open the carpet waste to a size of 0.3 to 30 mm.

(2) Sprinkle 3 to 30 parts by weight of urethane prepolymer on 100 parts by weight of the pulverized or opened product and stir.

(3) Before the prepolymer is completely cured, the mixture is taken out and pulverized to form an aggregate of 3 to 101 fibers and urethane.

(4) The aggregate is used as a raw material for felt.

There are no particular limitations on the carpet waste that can be used in this invention. Examples include the above-mentioned trimming waste generated from automobile carpet manufacturing plants, defective products, and discarded household carpets. The carpet that generates the waste may be made of polypropylene, polyamide, polyester, rayon, etc., or needle-punched, and the backing layer may be made of thermoplastic ell such as low-density polyethylene resin or EVA persimmon fat. Fat coated with T-die or EVA
There are those coated with latex such as SBR.

These carpet wastes are crushed to a size of 0.3 to 30 mm using a crusher or a hair opener. In the case of a hair opening machine, the fiber component and the resin component are roughly separated, but for this purpose it is preferable to use the fiber component.

Next, urethane prepolymer is sprinkled onto the carpet waste. As the urethane prepolymer, a prepolymer obtained by preliminarily reacting a polyether polyol and an isocyanate and containing a portion of unreacted isocyanate is used. This urethane prepolymer is sprayed in an amount of 3 to 30 parts by weight on crushed carpet waste. After being sprayed, the urethane prepolymer is cured by about 30 to 80% and then stirred or pulverized in large stages. At this stage, the urethane prepolymer is not completely cured and is relatively soft, so it can be easily stirred or crushed.

In this way, by stirring or crushing, an aggregate of carpet waste and urethane resin is formed.

After that, the urethane is completely cured by allowing it to stand still.

The assembly has a structure in which a certain number of carpet fibers and pieces of the backing layer are bonded together by a urethane prepolymer. The size of this aggregate is 3 to 10
It is about mm.

The formed aggregate can be used as a raw material for felt. For example, it can be placed in the middle layer of a cotton web and bonded with a thermosetting binder such as phenolic resin to form a resin felt, or it can be mixed with synthetic fiber waste and needle punched to form a needle punch felt. You can do that.

According to the treatment method of the present invention, the crushed carpet waste is bonded by phenolic resin to form an aggregate, so it is easy to get entangled when used as a raw material for felt, compared to the conventional method when used as is. There are no problems such as the extremely low proportion of contamination.

Furthermore, the felt produced using this raw material does not have the drawbacks of conventional car vent debris that separates and creates dust and pollutes the surrounding area, making it suitable for underfelts placed under car carpets. be.

Furthermore, after spraying urethane resin on the carpet waste,
Since the material is stirred or crushed before it is completely cured, only a very small amount of energy is required, which reduces costs.

[Example 1] Approximately 5 m of trimming waste from an automobile floor carpet
A prepolymer obtained by pre-reacting polyether polyol and isocyanate and containing a portion of unreacted isocyanate is crushed to a size of m, and water is added as a curing agent to 30 parts by weight per 100 parts by weight of the main material. 150g of the added material was sprinkled per 1kg of waste. Immediately after spraying, the mixture was stirred and then left for 3 minutes. Thereafter, before the added urethane was completely cured, it was stirred to form an aggregate of urethane and carpet waste about 7 mm in size. The assembly was left for half a day to completely cure the urethane resin. after that,
As lrn' of resin felt, 500 g per lrn' was uniformly dispersed in the middle of the cotton layer to make felt. The felt was suitable as an automobile under-heel without generating dust etc. (Example 2) An aggregate similar to that made in Example 1 was placed in a synthetic fiber bag with 100 synthetic fiber scraps. !Above-mentioned aggregate 80 for Okabe
A weight part was added and needle punched to form felt. This felt was also suitable as felt for automobiles.

[Brief explanation of the drawing]

FIG. 1 shows a flow chart of the carpet waste recycling method of the present invention. Further, FIG. 2 shows a conceptual diagram of an aggregate of carpet waste and urethane resin according to the present invention. 1. Carpet waste, 2. Urethane resin. 1 - ' Fee No. λ Figure 1 Figure 1 λ

Claims (1)

[Claims] A recycling method for recycling carpet waste, which comprises the following steps: (I) Pulverize or open the carpet waste to a size of 0.3 to 30 mm. (2) Sprinkle and stir 3 to 30 parts by weight of urethane prepolymer per 100 parts by weight of the pulverized product or open hair. (3) Before the prepolymer is completely cured, the mixture is taken out and pulverized to form a 3-10 mm fiber and urethane aggregate. (4) The aggregate is used as a raw material for felt.