EP2611585B1

EP2611585B1 - A method for manufacturing a door panel

Info

Publication number: EP2611585B1
Application number: EP11774121.5A
Authority: EP
Inventors: I. Hakki Yildiz
Original assignee: Yildiz Entegre Agac Sanayi Ve Ticaret AS
Current assignee: Yildiz Entegre Agac Sanayi Ve Ticaret AS
Priority date: 2010-09-02
Filing date: 2011-08-24
Publication date: 2014-09-24
Anticipated expiration: 2031-08-24
Also published as: TR201007332A1; WO2012030310A1; EP2611585A1

Description

Field of the Invention

The present invention relates to a manufacturing method according to claim 1 developed for the production of wooden door panels which have decorative exterior features and enhanced durability, which are used In the production of wooden interior doors that have a large field of work and manufacturing in the woodworking sector.

Background of the Invention (State of the Art)

There are several methods, with regard to the manufacturing of wooden doors for usage in the Interior of buildings, in the state of the art.
One of the most widespread of these methods is based on cutting and shaping wooden logs which are used as raw material and making them wooden doors. Although the end product obtained hereby is a wooden door which is highly durable and has enhanced insulating properties, it also has some technical problems which should be eliminated.
The most important ones of the aforementioned technical problems are that the door is heavy as a result of the fact that it is obtained directly from wooden log and that serious difficulties are experienced during transportation and assembly. Another problem is that the wood carving works performed in order to give the wooden doors a decorative shape are inconvenient, demanding and time consuming. In cases where this operation is conducted automatically with the assistance of machines, the high costs of these machines cause a significant increase in the prices of the doors. Moreover, since the number of the doors which can be obtained from each log is few and limited, the costs increase automatically and the amount of wastage reaches the point where It harms both the nature and the manufacturing.
GB 2 364 268 can be shown as an example of the prior art of this technical field as the Invention subjected to this document refers to a door obtained by securing a melamine Impregnated crepe paper or phenolic resin crepe paper coated Medium Density Fiber (MDF) board to a door frame. A chip board with a decorative reliefed layer is described in US 3 793 125 .
The wooden door manufacturing method which is developed in order to overcome all of these technical problems and which is used widely in the state of the art, in summary, consists of the steps of compressing and pressing the wood dust and making molded panels by oven baking the dust, and then, cutting these panels in appropriate sizes and obtaining the final product which is the wooden door panel.
The greatest advantages of the panel doors obtained in this way can be mentioned as; manufacturing in really high amounts from a unit of raw material thanks to the less material wastage, decreasing the manufacturing costs significantly and thus reducing the end-user prices to a minimum, eliminating the problems faced in transportation and assembly thanks to the panel doors obtained being light and rapid development of the sector with the increased manufacturing capacity.
However, in addition to the advantages, panel doors have disadvantages arising from some of the technical problems they have. The most important of these disadvantages is that the durability of the doors is reduced depending on the method of production and structural features. Another significant disadvantage is that, it is really hard, and even impossible, to give decorative features to a manufactured panel door with wood carving methods.
At this point, it is required to develop a decorative coating method which can be integrated into the manufacturing process of the panel doors in order to enhance the exterior visual properties of the wooden panel interior doors and to enhance the structural strength of the panel doors.

Brief Description of the Invention

The operational steps of the basic implementation of the door panel manufacturing method according to the present invention are as follows;

Obtaining chips from wood or other cellulosic raw materials,
Sifting the obtained chips,
Turning the sifted chips into fiber,
Adding chemical adhesives, binders and, optionally, chemicals which provide resistance against heat, moisture and fire, to this fiber structure,
Drying the fibers to which chemical adhesives, binders and, optionally, chemicals which provide resistance against heat, moisture and fire were added until they reach a moisture gradient of 8 - 10%,
Spreading the dried fibers and forming a 1810mm wide and 2230 ± 20 mm long shape outline,
Cutting the outline in the required sizes,
Spreading melaminous decor paper or finish foil paper on the cut parts,
Pressing the parts that are covered with melaminous decor paper or finish foil paper at 150 - 200 °C and 150 - 250 Bar pressure in the patterned swage inside the press; obtaining a 950 - 1100 kg/m³ dense, 3.2 ± 0.2 mm thick door panel which is resistant to heat, moisture, cracking and scratching, and covered with a patterned paper on the surface.

It is an objective of the door manufacturing method according to the present invention to produce a wooden door panel which;

is resistant to heat, moisture, cracking, scratching,
has a decorative exterior,
is light,
has low manufacturing costs.

Descriptions of the Drawings

The illustrations and the relevant explanations which are required to explain the door panel manufacturing method according to the present invention better are as follows:

Figure 1 : Flow chart of the paper-covered door panel manufacturing method

Descriptions of the Elements / Sections / Parts Comprising the Invention

In order to better explain the door panel manufacturing method develop according to the present invention, the parts and sections in the figures are enumerated separately and the descriptions of all numbers are mentioned below.

1. Door panel
2. Melaminous decor paper
3. Finish foil paper
4. Outline

Detailed Description of the Invention

In the basic implementation of the door panel manufacturing method developed according to the present invention, the utilized operational steps which make it possible to obtain a door panel which is resistant to heat, moisture, cracking and scratching and which is covered with a patterned paper on the surface, are as follows;

Chipping,
Sifting the chips,
Obtaining fibers from the chips,
Adding chemicals to fibers,
Drying and sifting the fibers,
Forming and outline with the dried fibers,
Spreading paper on the outline,
Hot pressing the paper-covered outline,
Cooling, sizing and packaging the obtained final product.

• Chipping:

At this stage, firstly the woods which will be used as raw materials fort he manufacturing of the wooden door are grouped according to their types (hardwood - softwood). Other cellulosic raw materials can be used instead of using wood as raw material. Then, the woods or other cellulosic raw materials which are grouped according to their types are chipped by being chipped in the chipping machine after being separated from their barks. The chipping is the process where the cutting blades on the revolving drum degrade the wood or the other cellulosic raw materials by cutting them perpendicular to their fibers. The obtained chips are then carried via transporter conveyors to silos or open areas and are stored herein.

• Sifting the chips:

The chips which are stored in the silo or in the open field according to their types are taken by transporter conveyors in wood mixture rates of 70 ± 10% pine and similar softwood, and 30 ± 10% beech and other hardwood; and are subjected to sifting. The sifting process is conducted in the disc sifter. In the sifting process; the chips are sifted by falling down from the discs on the machine and the spaces between these discs according to the sizes of the pieces. Furthermore, the chips are separated from fine dust, bark and large chips during this sifting process. The large chips are cut in the small chipper so that they have the appropriate size to go back to manufacturing and are, thus, included in the manufacturing process.

• Obtaining fibers from chips:

The sifted chips, which have appropriate sizes, are brought to the chips bunker of the fiberizer machine by the transporter conveyors. Here, after the preevaporation is performed, the chips are transformed into a suberose structure by being pressed with a pressure (suberization piston) applied by the auger conveyor on the opposite side. Afterwards, the suberose chips are carried into the scouring boiler of the fiberizer machine. Chips are boiled while being stirred, under a vapour pressure of 7,5 - 8 bar and a temperature of 160 - 170 °C for a time ranging between 2,5 - 6 minutes. As a result of the impact and centrifuge effect created by the blades on a revolving disc and a fixed disc, and the pressure coming from the scouring boiler, together with the vapour, the softened chips are transformed

• Adding chemicals to fibers:

Chemical adhesives, binders, and optionally, other chemical materials which provide resistance against heat, moisture and fire are added into the obtained fibers.

• Drying and sifting the fibers:

The fibers, the structures of which have added chemicals, are dried until they reach a moisture gradient of 8 - 10%. After the drying process, the fibers are subjected to a sifting process with an air-operated system; the caked fibers and fine dust metals are separated. Caked and thick fibers are removed from manufacturing and are collected in the waste silo.

• Forming the outline:

The dried and sifter fibers are collected in the fiber bunker called Spreading Bunker via the pneumatic conveying system. The fibers which are spread on the conveyor belt in 3.20 - 3.80 kg/m² set weights with a 2.5 - 3 m free fall are shaped and balanced (spreading and leveling the fiber). Afterwards the fibers, which go through the revolving cylinders of the front press and which have their air voids removed, are shaped into outlines of desired moisture, width, length and thickness with the help of the side shaping and crosscut saws.

• Spreading paper on the outline:

A chemical substance which has adhesive and coater properties is sprayed on the outline in order to make sure that the paper adheres to the outline and to increase the structural strength of the door panel. Then, melaminous decor paper or finish foil paper is spread on the outline which is prepared with the desired width and length. The papers to be spread can have the desired color, pattern and various weights.

• Hot pressing:

The outline which is covered with melaminous decor paper or finish foil paper is subjected to layered pressing under a temperature of 150 - 200 °C and a pressure of 150 - 250 Bar, in a patterned swage for 20 - 60 seconds; and thus, a door panel which is 950 - 1100 kg/m³ dense, 3.2 ± 0.2 mm thick, which is resistant to heat, moisture, cracking, breaking and scratching, which is easy to clean, ergonomic and which is covered with a patterned paper on the surface is obtained.

• Cooling, sizing and packaging:

The paper-covered panels which are out of the hot layered pres are left to cool for 1- 24 hours in order to prevent twisting and buckling. After the cooling process, the panels are sized by cutting them in desired width and length via circular saws. The panels which have undergone the sizing process are divided into quality classes and the paper-covered panels which have the same model and size are packaged as products that are available to the door manufacturers.
Within the scope of this basic concept, it is possible to have various applications of the door panel manufacturing method according to the present invention; the invention can not be limited by the examples which have been illustrated, and the invention is as it is mentioned in the claims.

Claims

A method for manufacturing door panels by using chipping, sifting, obtaining fibers, adding chemicals to fibers, drying and sifting, whereby these operational steps comprises of;
• Transporting the chips for sifting from silos or open areas via conveyors in wood mixture rates of 70 ± 10% pine and similar softwood, and 30 ± 10% beech and other hardwood,

• Boiling and stirring the chips under a vapour pressure of 7,5 - 8 bar and a temperature of 160 - 170 °C for a time ranging between 2,5 - 6 minutes for obtaining fibers,

• Drying the chemical added fibers until they reach a moisture gradient of 8 - 10%,

• Forming the outline by;
i. Shaping and balancing the fibers with a set weight of 3.20 - 3.80 kg/m² on the conveyor belt trough a 2.5 - 3 m free fall,

ii. Removing the air voids of the fibers through the revolving cylinders of the front press,

iii. Shaping the outline with the desired moisture, width, length and thickness by the help of the side shaping and crosscut saws,
and further comprising the additional steps of;

• Spreading melaminous decor paper or finish foil paper on the outline after spraying a chemical substance which has adhesive and coater properties on the outline,

• Subjecting the outline, which is covered with melaminous decor paper or finish foil paper as a whole, to hot layered pressing under a temperature of 150 - 200 °C and a pressure of 150 - 250 Bar, in a patterned swage for 20 - 60 seconds in order to form a door panel covered with a patterned paper on the surface,

• Cooling the door panel for 1 - 24 hours in order to prevent twisting and buckling,

• Sizing the cooled door panel by cutting them in desired width and length via circular saws to obtain the final product.
The method according to claim 1, characterized in that; melaminous decor paper or finish foil paper can be colored and patterned.
The method according to claim 1, characterized in that; melaminous decor paper or finish foil paper can be at various weights.