Elastic polyurethane foams for the production of upholstered furniture. Facing synthetic materials

Nikitina Svetlana Yurievna OJSC "VPKTIM".
Director of the Center for Engineering, Technical and Technological Support of Enterprises

Polyurethanes were first obtained in Germany in the late 1830s. In the development of polyurethane elastomers, Bayer chemists have produced end-products with unwanted gas bubbles. Then, already as a result of a targeted study of the interaction of polyhydric alcohols based on complex or simple polyesters with multifunctional isocyanates and water, a foam with a cellular structure was obtained. Over time, it has evolved into a multipurpose engineering plastic for mass-use polyurethane foam (PUF).

In the early 1950s, flexible polyester (PE) foams were the first to emerge, and then polyether foams were developed a few years later. In the 60s, with the discovery of rigid foams, the scope of PU foam expanded significantly, and by the end of the 90s they began to be used in almost all industries, and up to 70% of the total volume of elastic PU foam is used in the production of mattresses and upholstered furniture... At the same time, various polyurethane foam is used: light and heavy, soft and hard, obtained on the basis of various initial products and formulations of compositions, which make it possible to set a certain apparent density and rigidity, elasticity and the necessary shock-absorbing properties during its manufacture.

According to the manufacturing method, elastic polyurethane foam is divided into molded, when the parts are cast individually, and block, when the final product is large rectangular or cylindrical blocks, which are then cut into blanks.

The apparent density and rigidity of the material is of decisive importance for the use of block elastic polyurethane foam in various parts (zones) of upholstered furniture. Apparent density is the volumetric weight of a porous material. The stiffness of a foam can be viewed as the force with which that material resists deformation. The indicators of the apparent density and stiffness of polyurethane foam are interrelated: the higher the apparent density for a given stiffness, the higher the quality of the foam and less fatigue. In practice, this means that a higher load on furniture, the duration and frequency of its deformation must correspond to a higher apparent density. Only under this condition can the desired quality of the soft element be achieved.

It is impossible to give universal recommendations on the selection of the optimal apparent density for various elements of upholstered furniture, since their design and purpose are different, and the layers of the used polyurethane foam have different thicknesses. General recommendations boil down to the following: block elastic polyurethane foam for seats (high and frequent loads) should have the highest apparent density - not less than 28-30 kg / m3; material for armrests and backs (lower loads) - lower, but not less than 23-25 \u200b\u200bkg / m3; for thin floorings, the apparent density should be the highest - not less than 35 kg / m3 for seats and not less than 28 kg / m3 for backrests and armrests, since the thinner the flooring, the higher the degree of deformation at a given pressure (load).

The rigidity of elastic block polyurethane foam can vary widely depending on the initial formulations of the material used: depending on the apparent density, it can be super soft (from 0.5 kPa), soft, standard, hard and very hard (up to 10 kPa). Block elastic polyurethane foam of increased softness is used in furniture in combination with other flooring materials in the form of sheets of small thickness, for example, instead of batting; rigid - like a material that replaces, for example, springs.

The elasticity of the block PPU is determined by the size of the area of \u200b\u200bthe hysteresis loop when applying and removing a load. The smaller this loop, the higher the elasticity, and the faster its recovery after the removal of the deforming force, and vice versa. The wide possibilities of block polyurethane foam for the selection of elasticity during its manufacture allow you to create flooring materials with a wide variety of properties and combine flooring from them that exactly meet all the necessary requirements.

The disadvantage of block PU foam is the loss of some of their original properties after recovery in cases of excessive compression during transportation or storage. This is especially true for block foams with a density below 30 kg / m3. Block polyurethane foam is resistant to aging, and this is, first of all, resistance to prolonged exposure to moisture and temperatures. PU foam based on simple polyesters is more durable in furniture than on the basis of complex ones.

Numerous sanitary and hygienic studies carried out all over the world, including here in Russia, have proved that these materials, made according to a standard recipe, are absolutely safe for human health, and that the light weight, high air permeability, good heat and moisture exchange of the elastic PU foam allows us to accept it as the optimal material for the manufacture of mattresses. But its apparent density should not be lower than 30-35 kg / m3: otherwise, during operation under load, the foam cells are excessively deformed, which significantly reduces air and moisture exchange inside the product.

For complex volumetric soft furniture elements, molded polyurethane foam parts are used, which are manufactured in individual molds with high precision and do not require further refinement. The density of parts made of molded polyurethane foam is significantly higher than that of parts made of block polyurethane with similar physical and mechanical characteristics: for the backs of upholstered furniture not less than 42 kg / m3, and for a more loaded seating area not less than 45-48 kg / m3. And the density of the molded foam for office furniture, due to the small thickness of the soft element and the increased requirements for wear resistance, should be even higher - from 55 to 70 kg / m3.

Due to the high adhesion of polyurethane foam to almost all materials, the molding method makes it possible to simultaneously use embedded parts: metal frames, spring blocks and other structural elements with the formation of a durable connection. Their use simplifies the technological process of making upholstered furniture, since a finished assembly unit is obtained in one operation. But furniture production is characterized by a constant change of assortment and a relatively small serial production. Due to the constant change of molds, the price of which is very high, the cost of parts made of molded polyurethane foam is higher than that of parts made on the basis of block.

Despite the general growth in the production of upholstered furniture, for last years the production of molded foams in Russia is constantly decreasing. This is due to the wide development of enterprises producing cheaper block polyurethane foam and almost completely covering the needs of upholstered furniture manufacturers. Molded polyurethane foam occupies a very small but permanent niche mainly in the production of high-quality and highly artistic upholstered furniture. But small suppliers of molded polyurethane foam can only produce a very limited range of simple-shaped elements. Therefore, as in the rest of the world, the future belongs to the larger manufacturers of such parts. But the organization of mobile production of high-quality molded polyurethane foam with a constant change in the range of products is associated with significant capital investments and requires highly qualified personnel.

One of the largest manufacturers of a wide range of high quality molded polyurethane foam is Europlast LLC (Moscow). There are few manufacturers who are ready to supply products to order in small batches. And the main flooring material for upholstered furniture is still block PPU. But in recent years, the volume of production of upholstered furniture has increased, especially furniture of the middle and high price level. There are even enterprises that supply upholstered furniture for export. And the quality of this furniture, which is not immediately noticeable to the consumer, but which he begins to evaluate only after its long enough use, is precisely determined by the quality and correct selection of the PUF used in it.

JSC "VPKTIM" provides services in the areas of production and application

Institute of Furniture (JSC "VPKTIM") has a check and independent examination of the quality of flooring materials in the field of furniture.

When buying a sofa or armchair, you pay attention to their appearance and are not interested in the inner content - Internal filling sofas and armchairs is not simple - Fillers for upholstered furniture - The inner filling of sofas and armchairs can be varied - PU foam - Spring blocks - Independent springs - Various transformation mechanisms - Mattress

Furniture polyurethane foam - PPU

Polyurethane foam (furniture foam rubber, abbreviated as polyurethane foam) is one of the most common flooring materials for the production of upholstered furniture and mattresses. is a foamed, sponge-like material obtained by mixing several synthetic polymers. The peculiarity of modern polyurethane foams is extremely high physical and mechanical properties, which in some parameters are superior to all types of rubbers and rubbers. Today's market offers a very wide range of different brands foam rubber: standard, increased rigidity and hard, soft and super soft, highly elastic. Each of the types foam rubber differs in its quality characteristics and has its own purpose in the manufacture of upholstered furniture.

Polyurethane foam (PPU) - high-volume material with a porous structure. It is used in a variety of applications - as a seat base for theater chairs and driver's seats. Polyurethane foams are also used as filler for the production of upholstered furnitureas well as in spring mattresses, and on your own in springless mattresses. Seats sofas and armchairs from furniture foam rubber rather elastic, easily restore their original shape. Sitting on such a sofa is comfortable, it adapts to the shape of the body, and it is easy to get up from it. Due to its qualities polyurethane foam is one of the most popular fillers for upholstered furniture.

Foam rubberpurchased for the products of our furniture factory Alina, produced on Norwegian (LAADER BERG AS) and German (FECKEN-KIRFEL and ALBRECHT BAUMER) equipment. Quality of the produced foam rubber achieved through automation of the production process and high-precision dosing of components. Strict adherence to production technology and a quality control system, as well as high qualification of personnel and high-quality raw materials from leading manufacturers, allow achieving the most positive characteristics of foam rubber, which makes it competitive.

Upholstered furniture filler - PPU (furniture foam rubber) - not only has a low cost, but also unique properties, which in turn determine its popularity:
* the possibility of transformation, various rigidity, reliability, durability.

Besides, for furniture foam rubber there are also many other important properties that you need to pay attention to. They are mainly associated with direct effects on humans. PPU (furniture foam rubber):
* does not contain substances that cause allergies, does not accumulate and does not emit dust, does not grow moldy, safe for human and animal health.

All used polyurethane foam meet the world standards of hygiene, processed with antibacterial, antiviral and antifungal composition.

Equipment and industrial lines for the production of polyurethane foam - for familiarization with the customers of furniture products (note !!! the factory "Alina Mebel" is not a manufacturer of polyurethane foam, but only uses it as an internal filler in the manufacture of upholstered furniture)

So, polyurethane foam is a high-tech filler for upholstered furniture, which is characterized by increased strength and durability. By its structure, polyurethane foam consists of microscopic thin-walled cells filled with air. The properties of elasticity and resilience are determined by the fact that the volume of air in the total volume of the material exceeds 98%. For the production of foam rubber of any type, special polyols, melamine, fire retardants are used in the formulation so that the physical and mechanical parameters (density, stiffness, cell size, elasticity, tensile strength, air permeability, permanent deformation, relative elongation) meet the requirements of the Consumer.

Furniture with polyurethane foam filling characterized by increased strength and durability

In the furniture industry, various brands of foam rubber are used with high strength indicators. They are used as filling sofas, armchairs and other types upholstered furniture, which increases the comfort of the models.

Each brand of PPU has its own purpose. Typically, different brands of foam rubber are used in combination with each other. Some are for parts of furniture that do not bear the main load: backs of sofas, armchairs, armrests. Others - for places of moderate loads during the operation of furniture. Still others are for use in conjunction with transformation mechanisms, etc.

Furniture factory Alina uses mainly dense, highly elastic grades. All brands polyurethane foamwe use are safe, non-allergenic and dust-free. These foam rubber has a hygienic certificate from the Ministry of Health, which allows its use in the furniture industry.

Foam rubber the brands used also have a high degree of "air permeability". With the correct use of these brands, this indicator indicates the possibility of a long service life, good ventilation of products and the relative comfort and durability of products. Quality indicators are stably maintained under long cyclic loads, which significantly increases the service life of the furniture. They have good sound-absorbing and insulating properties.

Furniture polyurethane foam is a hygienic material that, with proper care and use, will last a long time, so you don't have to worry about the durability of your upholstered furniture.

Sintepon

Sintepon(in common parlance, sintipon or sentipon, sintepon or cintepon). What it is? What is he? Why is there so much talk about him? Is it good or bad? Is it harmful to health or not? Sintepon - is an environmentally friendly elastic material with a high degree of elasticity. The synthetic winterizer is used as a filler in the production of upholstered furniture - sofas, armchairs, poufs - to give the seats and backs an angular relief while maintaining acceptable softness and comfort. Sintepon for a long time does not lend itself to oxidation by atmospheric oxygen. The synthetic winterizer is moisture resistant and does not absorb moisture into the fiber structure.

Sintepon is volumetric non-woven fabric made of polyester fiber. According to the method of joining fibers, it can be thermally bonded and glued. Sintepon - an elastic-elastic material, used as a filler in the furniture industry in the production of upholstered furniture, serves to give it relief and softness. Sintepon - flooring material made of solid acrylic fibers arranged in parallel strands. Usually a layer of padding polyester is covered with furniture foam rubber - PPU.

Sintepon is one of the most affordable fillers. Its development is not difficult and is a fast and low-cost process. Sintepon is a lightweight, resilient and voluminous nonwoven material that is used for various purposes and is distinguished by great functionality along with good thermal insulation properties. Sintepon also goes as a filler in bedding, blankets, clothes, including baby overalls. Sintepon - one of the few artificial materials that do not cause allergies in anyone. Therefore, it is also used in the children's industry as a filler for pillows and clothing.

Sintepon is environmentally friendly, does not lend itself to light-zone aging for a long time, resists fungal contamination, does not absorb moisture, is absolutely harmless. Recently, technological developments have led to the emergence of a fundamentally new high-quality synthetic products called holofiber, which in fact are no longer a synthetic winterizer.

Recently, technological developments have led to the emergence of a fundamentally new high-quality synthetic products. holofiber, which in fact is no longer a padding polyester.

Fillerfiber - these are siliconized polyester balls, replacing natural fluff. - one of the most modern materialsused by in the production of upholstered furniture... The microstructure of the holofiber is a spatial spiral (as opposed to straight fiber, as in padding polyester), which allows it to perfectly maintain its shape and easily restore it. It is more hygienic than natural and others synthetic fillers, moisture resistant, comfortable and cozy. It is an environmentally friendly, non-allergic and non-toxic product.

Filler fiber is a siliconized fiber that is formed into balls on special equipment. Due to this, unlike synthetic fiber, which is a budget option, it is tightly packed into the pillow and after distribution is a tightly stuffed object, a fiber pillow, which is loosely packed and allows the fiber to move inside the pillow, creates a unique shape suitable only for you.

Holofiber - material for stuffing pillows in the form of balls-cocoons made of synthetic spiral fibers treated with silicone. The balls are twisted fiber treated with silicone emulsion. The fibers, intertwining with each other, form a springy structure. This property allows the fiber to quickly regain its shape after crushing and has a high resistance to retention of its shape over time. The structure of the fiber is soft, breathable, has anti-allergenic properties, does not absorb foreign odors, does not form dust, does not roll into lumps. This filler is non-flammable (melts, but does not support combustion).

Fiber fiber has unique qualities:

Long lasting. Finished products using holofiber quickly recover their shape after compression and are especially soft.

Ecologically pure high-tech fluff substitute fiber does not cause allergies, which is very important for health modern man... Unique filler quality: hypoallergenic. The most important property of fiber filler is its hygiene, the ability not to absorb odors and dust, and as a result, the absence of allergic reactions upon contact.

Orthopedic properties. A particularly valuable quality of fiber filler is manifested in the fact that products from it take the shape of the body. The sophisticated processing technology of the fibers allows them to move independently of each other, so the strong, springy structure does not collapse after prolonged use.

Antistatic properties. The special antistatic treatment of our products is absolutely harmless to health.

Environmental Safety. The environmental friendliness and non-toxicity of fiber fiber has cemented its reputation as the most popular filler.

Cozy microclimate. Fiber is composed of many twisted fibers, leaving an air space between them, which allows the filler to "breathe".

Durability. Fiber fiber will not lose volume during operation like cheaper synthetic fillers. A product with such a filler easily returns to its original shape, even after prolonged deformation.

Fiber combines Important consumer properties, such as:

1.do not cause allergies - hypoallergenic
2.Anti-static
3.special thermal insulation and breathability
4.orthopedicity, firmness, elasticity, lightness and bulk
5.Eco-friendly and durable
6.Is an excellent substitute for natural fillers

Products using holofiber provide maximum convenience and comfort during rest and sleep. Fiber not inferior to down in softness, elasticity and comfort, while absolutely hypoallergenic.

The name of the filler, the cheapest filler in existence that is widely used in furniture production... Today it is the best alternative to natural down. This fiber is treated with a special silicone emulsion, which gives it qualities that make it an artificial fluff substitute. - this is artificial fluff - a hollow highly crimped siliconized fiber, 100% polyester, a single component of which in space looks like a spiral spring. Coil length 57 mm. These single components, intertwining with each other, form a strong springy fiber structure. This property allows the synthetic fluff to quickly recover its shape after crushing, to have a high resistance to maintaining its shape over time. The elastic, compressible structure of padding polyester is soft, breathable, which does not create a "greenhouse effect" with prolonged use.

Lightness, softness, elasticity, volume, warmth, environmental friendliness, hypoallergenicity, resistance to washing and dry cleaning has such qualities synthetic fluff... The hypoallergenic and environmental friendliness of synthetic fluff is explained by the absence of substances harmful to human health in its production. In addition, synthetic fluff does not absorb extraneous odors. not afraid of water, getting wet, it still retains heat.

Synthetic down does not roll or fall off, which cannot be said about natural down... used as filler for backrests, armrests and decorative pillows and other products of upholstered furniture.

A multi-layer, highly elastic, thermo-bonded fabric with vertically directed fibers and aerodynamic layout, which has low permanent deformation. - white, soft, delicate polymer. It has oriented vertical fibers and therefore works like a spring block. This soft and lush filler in the manufacture of upholstered furniture, they are used as a filler for seats, backs and armrests of sofas and armchairs. Upholstered furniture made using durafil filler has the best consumer characteristics: the seats and backs of sofas have the ability to restore their shape after pressing or weight loading, while retaining this feature for a long time.
does not cause allergies, does not absorb moisture and does not support combustion. Colonies of dust mites, butterflies, moths and molds do not grow in the filler. Right choice types of flooring materials and their competent combination largely determine the quality and comfort of upholstered furniture. As auxiliary flooring materials in production, they are used: batting, quilted jacket, felt, spunbond and many others.

(type of non-woven) - non-woven fabric obtained by calendering (rolling through hot rollers) polypropylene fibers. AT spunbond the seat and back cushions are wrapped, used as a technical fabric. This makes it easy to put on the fabric covers as the fabric slides over the spunbond. During operation spunbond protects soft materials from abrasion and pilling, and also allows you to straighten the folds of the cover. Non-woven - non-woven fabric, used to add volume and reinforce the fabric, prevents the fabric from stretching, reduces creasing, does not change the properties of the fabric, maintains the size and shape of the product during use. Of spunbond inner covers for back cushions and decorative pillows are sewn. Properties: hypoallergenic (used in the production of hygiene products), non-toxic, tear-resistant, breathable.

Polystyrene balls

Foamed polystyrene - foam balls, a lightweight cellular material consisting of hydrogen and carbon atoms. They are very mobile and do not form friction with each other, which allows products with this filler to quickly take a given shape. Is an filling of armchairs and poufs "Bin-Beg".
The cover is stuffed with many small polystyrene balls. The advantage of the model is lightness, therefore, if necessary, the chair can be easily transferred from room to room. The weight of Bean-Runs ranges from one to five kilograms, depending on the size. Made from durable beautiful fabrics, Bean run are filled with extremely light expanded polystyrene balls... Balls deform over time under the weight of a person - this is a natural process. There is a zipper at the bottom of each item so that the cover can be washed or added expanded polystyrene filleras it shrinks. The use of a unique technology made it possible to relieve the products from the accumulation of static charge and rustling, so it is a pleasure to be in them! Bean-Run Filler must be treated with antistatic agents and components to reduce friction (15-20 times) - this is a distinctive characteristic of the filler for poufs. The expanded polystyrene filler does not "creak" and does not accumulate static electricity!

Quilted jackets is a cotton wadding covered with fabric on one or both sides and stitched with threads. For the manufacture of quilted jackets, fabrics are used: packing, bag, technical calico, gauze. Quilted jackets quilted with thread on sewing machine parallel rows with a certain distance between the rows.

In this way, padded jacket flooring - natural material , is two layers thick fabric with a 5 cm layer of cotton wool between them. Quilted jacket - one of the fillers for upholstered furniture. Technologically decking quilted jacket the spring block is covered to give more softness and evenness to the sleeping place of sofas. Quilted jacket It is widely used in the furniture industry as a cushioning material between other sofa fillings, as well as to increase the comfort of a sleeping place.

- dense non-woven fabric made of felted wool. It is usually made in the form of panels, which have different thicknesses, depending on the purpose.

AToilok - one of the obligatory fillers of upholstered furniture, natural materialrolled through hot cylinders on both sides. A hard crust forms on the surface of the material, which makes the material very wear-resistant.

Used by at furniture factoriesin production upholstered furniture - sofas and armchairs as a cushioning material that serves to neutralize the feeling of springs and protects polyurethane foam - PUF from contact directly with the spring block, prevents it from being pushed through, and also improves the consumer properties of upholstered furniture.

Rubber belts

Most often, in furniture upholstery, a frame formed furniture tapes - belts... They are located in the inner part of the seat and backrest, and for greater strength they are intertwined perpendicular to each other. The ribbons are usually very tight and should completely cover the space where the springs or filler will be located during the production or upholstery of furniture.

Rubber belts consist of rubber and synthetic fibers, pressed and glued together. Rubber belts stretched in the form of a net on a wooden frame - this is a kind of bases sofas and armchairs, chair backs... They are tensioned by a special machine that ensures uniform belt tension. have varying degrees of stretch. Softer belts are used on the backs of upholstered furniture, harder ones are used on the seats of sofas and armchairs.

Plate for transformation mechanisms

are made on special equipment from beech or birch veneer. In recent years, beech armor has been rare. Perhaps the reason is that they are much more expensive than birch. Lata is a bent-glued product. The layers of wood are glued together using a special technology, due to which a bent product ( latu), which has the ability to bend under the load exerted on it. On a metal frame armor are in special plastic lat-holders, which are fastened with brackets over the frame. So armor hold tight and do not pop out. also installed as a base for the decking of some models of upholstered furniture, as well as for metal frame mechanisms for transforming sofas and armchairs.

Breakage or deformation (loss of bending) are the main defects of bent-glued elements. Lata breaks, as a rule, in the middle part of loads exceeding the norm. Deformation is understood as the process of natural wear and tear during operation. It must be said that the more armor is installed, the less each of them is deformed. The damaged plate bends in the opposite direction or becomes straight. The battens cannot be repaired, therefore, in case of breakage or deformation, they are replaced.

"Snake" (snake spring block) - is a type of springs that are used in the furniture industry. "Snake" works in tension and in most cases they are used in the base of soft elements, such as seating furniture... Springs are attached to the frame of the sofa across.

The number of springs placed in furniture depends on its size, as well as on the purpose. Spring snake can be used in beds, couches, mattresses, as well as sofa beds. Such springs can be attached different ways... The frame of the product, which has a base of these springs, is stable and does not swing. The main advantages of using the "Snake" springs are the smooth base of the sofa, as well as noiselessness.

Springs of sofas and armchairs made of galvanized metal and shaped like " snakes". In the manufacture of seats, wires of a large cross-section are used, so they are more rigid than on the back. In order for the seat" not to sag ", the spring is well hardened. Snake springs give upholstered furniture - sofa and armchair elasticity and orthopedic effect. They are installed on the frame as a base for soft elements, providing comfort and reliability in operation.

Spring blocks

Spring block is a block of interconnected springs. Each spring in the block operates separately to ensure orthopedic effect... Well-known spring block widely used in manufacturing upholstered furniture... It is constantly being modified to improve its qualities. Main function spring block - keep the spine in the correct position. Design features help fulfill this function. Each spring adapts to a specific area of \u200b\u200bthe body, without transmitting movement waves. Uniqueness independent springs in that they unload the spine as much as possible. Spring block provides free air circulation and a healthy sleep climate. Factory Alina Furniture uses spring blocks "Pocket Springs" and "Bonnel".

Bonnell spring sofas

Bonnell continuous springs frame is one of the oldest spring frame designs. Sofas with double cone spring block Bonnell produced by all Russian and many Western firms. They belong to the most common group. It consists of 5 turns bicone springs of high-quality steel wire (diameter 1.6, 1.8, 2.0 or 2.2 mm), interconnected by staples or wire, with special nodes for additional rigidity.

Due to progressive elasticity, the spring at the beginning of the load is soft (amenable to compression), and as the load increases, it becomes harder, which creates a relatively uniform distribution of body weight and its convenient location, and also makes it possible to avoid contact of the coils, friction and squeak.

Materials are used as hard (to neutralize the feeling of springs and increase the rigidity of the mattress) and soft (for comfort, air and moisture exchange) fillers: spunbond, felt, polyurethane, batting, etc.

Advantages:

• Spring block Bonnell withstands heavy loads. For people with a large weight - over 110 kg, mattresses of this series are recommended.
• Long service life (durability) - spring block Bonnell retains its elastic properties for a long time.
• Since the two-cone spring block creates a large volume of air in the mattress, then such a mattress has a good moisture exchange (additional effect of bellows).

All materials used for the production of sofas with Bonnell springs are subjected to a series of tests and are made up of high-tech compounds of natural fibers. All products are certified in accordance with hygiene standards.

In the manufacture of products, the world's most advanced technologies for working with spring blocks are used. Upholstered furniture has unique properties: environmental friendliness, elasticity, durability, ergonomics, aesthetics, and an unsurpassed sense of comfort.

Filling of upholstered furniture products meets the world standards of hygiene, treated with antibacterial, antiviral and antifungal composition, hypoallergenic.

Sofas with independent springs

In our time, sofas with independent springs have become very popular.

The coil springs are sewn into separate textile pockets. For pockets, materials are used that allow air and moisture to pass through. Separate pockets with springs are connected to each other. These connections must be flexible so that each particular spring can exhibit its elastic properties.

It is believed that the more springs, the better the anatomical properties of the mattress - in part this is not the case. The optimal number of springs (up to 350 per sq.m.). If there are more springs, then they become too narrow at the same height. Under load, the deformation of the springs occurs not in one plane (up and down), but in two or more planes (bending at the sides) and entail other springs, which negatively affects the anatomical properties of the mattress and its quality.

The frame with barrel springs in the pockets, in contrast to the Bonnell spring frame, has the properties of point elasticity and, therefore, very easily conforms to the shape of the body, i.e. mattresses with such a frame are orthopedic.
However, despite the good flexibility, mattresses with pocket springs should not be used for automatically adjustable bed slats.

The anatomical properties of a mattress are determined by its ability to distribute the load of the body as evenly as possible during sleep, assuming its shape.

Main materials:

• Spring wound from special grade steel spring wire, hardened with high voltage current. For each spring of the block there is a piece of wire with a length of 110 cm. For the manufacture of 1 m2 of a spring block, 282 m of wire are used.
• Non-woven fabric cover. It is durable, tear-resistant, has excellent flow and filtration capacity. Each spring of the block in a compressed state is in a separate case-pocket, thereby providing the necessary reserve of elasticity, supporting the properties and durability of the spring block.

Purpose:

• Block of independent springs used for production orthopedic mattresses... The functional purpose of the block is to support the spine in the correct position. This task is realized through its design features. Each spring adjusts to a specific area of \u200b\u200bthe body without transmitting displacement waves: that is, if the load is applied to one specific spring, adjacent springs are not compressed. But first of all, independent springs are unique in that they maximally unload the spine.
• Block of independent springs serves as a support for all components of the mattress. Its surface is ideal for adhering fillers (eg latex cloth). In addition, such a unit provides free air circulation and takes care of a healthy sleeping climate.
  The durability of the mattress depends on the quality of the block.
• Independent springs come in various heights and diameters, which provides the spring blocks with different properties. Thanks to their increased comfort and multi-purpose use, the independent spring units are the product of the future.

Equipment and industrial lines for the production of springs - to familiarize customers with furniture products (note !!! "Alina Furniture" factory is not a manufacturer of springs, but only uses it as an internal filler in the manufacture of upholstered furniture)

Block of independent springs has special ergonomic and mechanical properties. It consists of cylindrical, or barrel-shaped springs, each of which is in a closed pouch and does not have a metal bundle with the others. Compression of each individual spring in the block occurs independently of the adjacent springs, so the mattress adapts to the shape of your body. The advantages of a mattress with independent springs are obvious. The springs are not attached to each other, so there is no "wave" effect.

A sofa with comfortable filling will not cure back illnesses, but it will help relieve tension and fatigue in the muscles, relieve the spine. The most pronounced orthopedic effect have sofas with a block of independent springs that follow the contours of the body and allow the muscles to completely relax due to the even distribution of the load. Block of independent springs the standard configuration consists of insulated coil springs that do not have a rigid metal bond. Due to this, the mattress itself "adjusts" to the shape of your body.

The filling of the manufactured products of upholstered furniture meets the world standards of hygiene. It is processed with antibacterial, antiviral and antifungal composition, hypoallergenic

LLC "RIF-Ametist" is engaged in the production of many synthetic materials, including polyurethane foam. We actively accept orders for polyurethane foam for furniture, meeting the highest requirements of domestic manufacturers. Our company produces several types of polyurethane foam, serving the wide demand for PU foam of various physical and chemical characteristics.

Advantages of polyurethane foam for furniture

Polyurethane foam is used in many industries and there are specific requirements for each application. It has received such wide distribution due to its special characteristics, a unique combination of which allows achieving very high results. Flexible polyurethane foam for furniture has the following features:

1. High levels of breathability.
2. Good moisture exchange and heat retention.
3. Light weight polyurethane foam products.
4. Relatively low manufacturing cost.

Thanks to these characteristics, polyurethane foam has become one of the most convenient and profitable materials for any industry, including furniture.

According to its physical and chemical properties, all polyurethane foam for upholstered furniture can be divided into several main types, which, in turn, can also be divided into subspecies with more accurate characteristics.

Types of PPU

The following types of polyurethane foam can be cited as an example:

1. Standard PPU (ST);
2. Polyurethane foam with increased rigidity (EL);
3. Rigid PU foam (HL);
4. Soft polyurethane foam or with increased softness (HS);
5. Highly elastic polyurethane foam (HR *);
6. Highly resilient fireproof polyurethane foam (CMHR).

These types of polyurethane foams are used to make backs, seats, mattresses and other products for the furniture industry. All types of materials listed above differ from each other in their properties. These properties affect the most important indicator - the load that can be exerted on the product. The softer the material, the less stress it is ready to endure. Stiffer or more elastic types of PU foam can withstand loads of more than 120 kilograms. The correct choice of material for the product is the key to its long service life.

Block and molded polyurethane foam

There are two main ways to produce PU foam: in blocks and by molding. Block polyurethane foam is widely used and is mainly used for typical solutions. In contrast, molded polyurethane foam for furniture is produced for both simple and complex parts. It is poured into special forms, and the result is an element made of polyurethane foam and exactly corresponding to the dimensions of the blank of the future furniture element.

Special types of polyurethane foam

Polyurethane foam is a special synthetic material, the invention of which became a real breakthrough for the industry. Of course, a lot of scientific research is carried out annually, which are aimed at the invention of new types of polyurethane foam, which will be able to solve the still unanswered problems. Today, there are already such special types of polyurethane foam as fireproof polyurethane foam resistant to fire, polyurethane foam memory foam, which is distinguished by the characteristics of increased comfort, and others. Do you want to use special materials to manufacture your furniture? Contact us to find out what kind of PUF better fit for a new product.

Order the production of polyurethane foam for furniture

You still have questions about which better materials to use to make a new batch of furniture? Would you like to know more about the possibilities of our production? LLC "RIF-Amethyst" will provide you with all the information about our products and our services, detailing the data in the most convenient form for you.

Are you interested in the opportunity to order the production of polyurethane foam for upholstered furniture? In this case, we are ready to offer you our services. For many years we have been serving domestic furniture factories and will be happy to offer our services to you. To place an order for the production of polyurethane foam for furniture, just call the duty manager of RIF-Ametist LLC. He will take the order and answer all your questions. After discussing the details of your project, we can tell you the exact cost and production time.

(in the mattress) - polymer material with a gas-filled structure, in which more than 85% of the volume is occupied by air. Depending on the parameters of the polymerization reaction, various types of polyurethane foam (PUF) are obtained, from hard plastics to soft foam compounds. In the furniture industry, flexible polyurethane foam of varying degrees of rigidity is used.

Mattresses based on this material differ in different rigidity (depending on density), durability and environmental safety.

The history of foam mattresses and their use in the furniture industry

PPU was originally synthesized in 1937 at IG Farben's laboratory in Leverkusen. There, the German chemist Otto Bayer discovered both forms of this substance: both rigid and elastic. Immediately recognizing the commercial potential of the material, as well as its wide range of applications, Bayer began to actively disseminate information and offer manufacturers this substance as a filler for upholstered furniture. However, the Second World War prevented the spread of a springless polyurethane foam mattress in those years, and it became widespread already in the sixties.

What is a polyurethane foam mattress in a sofa?

PU foam can be used in the manufacture of mattresses in two versions:

	As the main material of which the mattress is made. In this case, the product is a structure of one or more polyurethane foam layers of varying degrees of rigidity. Such a mattress is distinguished by a sufficiently high level of comfort, as well as ideal silence during operation: the springless solution eliminates any creaks and noises. In addition, the product is highly elastic and durable.
	As an element of a complex mattress structure. A common solution is to use a PU foam interlayer as the outer lining of the spring block. In this case, the PU layer provides additional comfort and softness. It also significantly increases the durability of the product.

Modern mattresses made of polyurethane foam (or with polyurethane foam) are completely environmentally friendly, do not have foreign odors and are extremely durable.

Types of polyurethane foam used in mattresses and their features

First of all, it should be noted that PUFs of different density are used.

The most popular are 35 kg / m3. (more expensive and hard and elastic) and 25 kg / m3 (most common in sofas, medium hardness).

The degree of rigidity of the product depends on the density (the higher the density, the heavier and tougher the mattress), as well as its endurance. By increasing the rigidity, we increase the permissible load.

With a density of 25 kg / cubic meter. the maximum load is 100 kg per berth, while 35 kg / m3. already increases the limit to 130 kg.

The following types of PPU are used:

• Standard - no modifications, with a density of 25 to 35 kg / m3.
• Increased rigidity - with the addition of polymers, increasing the density. Used to create hard beds.
• Soft and super soft - made from modified raw materials with the addition of special substances that soften the foam. For those who like a softer bed.
• Latex polyurethane foam or “with memory” is soft, but its main feature is “memorizing” the shape of the body by reducing elasticity. It does not straighten instantly, but keeps its shape, thereby allowing you to achieve maximum comfort.

Polyurethane foam mattress in the sofa: reviews

The owners of these mattresses note that the products do not have any foreign odors, are light enough (therefore it is not difficult to move them, put them, etc.), and are also very comfortable. At the same time, many owners note the durability of the product: it retains its elasticity and original properties for a long period of time.

Polyurethane foams (foamed polyurethanes, polyurethane foam) Are gas-filled, rigid or elastic.

Composition of polyurethane foams

Compositions for the production of polyurethane foams contain isocyanates, hydroxyl-containing oligomers, water, catalysts, emulsifiers, and in some cases fillers, colorants and flame retardants.

Compositions for production flexible polyurethane foams includes simple oligoesters with 750 - 6000 synthesized from oxides alkylene (, propylene), tetrahydrofuran and glycols... Less commonly used complex oligoesters of dicarboxylic acids (adipic, sebacic, amber) and glycols (for example, diethylene glycol). Rigid polyurethane foams are obtained from branched oligoesters based on alkylene and triol oxides (glycerin, trimethylolpropane, etc.) or complex oligoesters based on dicarboxylic acids (adipic, phthalic, etc.) and triols or mixtures thereof with diethylene glycol... The density of the resulting polyurethane foams depends on the ratio and hydroxyl-containing oligomers in the original mixture. With an excess of isocyanates, polyurethane foams contain more urea groups than with a lack of isocyanates, when more urethane groups are formed. Since polyureas have a lower density 1.05-1.23 g / cm 3) than polyurethanes 1.28 g / cm 3), in the first case, polyurethane foams with a lower density are obtained.

Obtaining polyurethane foams

Polyurethane foams are obtained by interaction di- or polyisocyanates from simple or complex hydroxyl-containing polyesters in the presence of water and catalysts. The blowing agent is carbon dioxide (CO 2)released by the reaction isocyanates with water:

In most cases, catalysts are used tertiary amines and about lovoorganic compounds... In addition to these components, auxiliary substances are introduced into the foam formulations - foam stabilizers, additional foaming agents (for example, freons), dyes, etc.

Polyurethane foams can be divided into two groups:

1. flexible foams based on linear or slightly branched polyesters;
2. rigid foams based on highly branched polyesters that form polymers with a higher degree of crosslinking.

The density of the polyurethane foam is adjusted by changing the water content. The more water is introduced, the lower the apparent density of the foam. For example, when obtaining elastic polyurethane foams with an apparent density 32 kg / m 3 about 75% isocyanate groups react with water and only about 25% interacts with the hydroxyl groups of the polyester.

As a result of side reactions during the synthesis of polyurethane foams, along with urethane, other bonds are formed. So, primary amino groupformed during the interaction of isocyanates with water, is capable of reacting with isocyanate group:

The reaction product is a substituted urea, which contains mobile hydrogen at nitrogen and is capable of interacting with isocyanates, as a result of which crosslinking of individual polymer macromolecules can occur at elevated temperatures ("Urea" crosslinking):

Cross-links can also form during the interaction of isocyanate and urethane groups, as well as during the trimerization of isocyanate groups remaining in macromolecules, in:

Interaction isocyanate groups from hydroxyl-containing oligomers and water - competing reactions. The role of the catalyst is to regulate the rate of the above reactions. In this case, the evolution of gas and the growth of polymer molecules should occur at such rates that the gas remains in the polymer, and the resulting foam would be strong enough and would not fall off.

Most often as catalysts apply tin compounds (oleate and octoate, dibutyltin salts, etc.), which regulate the formation of urethane units, and tertiary amines (triethylamine, triethanolamine, dimethylbenzylamine, etc.), catalyzing the reactions of the formation of a three-dimensional structure and the release of carbon dioxide. In practice, a catalytic mixture is used consisting of a tin compound and one or more amines. The polyurethane composition can also be foamed low boiling liquidsusually freons.

The chemistry of the formation of flexible and rigid polyurethane foams is the same. Rigid foams differ from elastic foams in that they consist of polymers with a large number of cross-links. In rigid polyurethane foams, the average "molecular weight" of a structural unit per one network branching point is 400 - 700 , in flexible polyurethane foams - 2500-20 000 ... Therefore, compositions for the production of flexible polyurethane foams do not contain trifunctional hydroxyl-containing oligomers (or contain them in small amounts), and also contain less tertiary amines.

An obligatory component of the composition is emulsifier, which promotes a high degree of dispersion of components in the mass and plays the role of foam stabilizer at the moment of foaming. To do this, use sulfoalcohols, sulfonic acids, organosilicon liquids, etc. Some stabilizers (for example, paraffinic hydrocarbons, organosilicon liquids) determine nature (open or closed) and size of pores formed.

Antimony trioxide, trichloroethyl phosphate, powdered, etc. are used as polyurethane foams. Most organic dyes are suitable for coloring polyurethane foams. Fill polyurethane foams with talc, expanded clay, fibers of various nature.

Polyurethane foams produce by foaming the composition with gasesreleased as a result of reactions between the components of the initial mixture (see above), or using low boiling liquids... Since a significant amount of heat is released during the formation of polyurethane foam according to the first method, the internal elephant of large-sized products can be charred. Therefore, the first method is applicable only for the manufacture of products of small thickness.

In the second method, the released heat is spent on the evaporation of a low-boiling liquid, which prevents local overheating and carbonization of polyurethane foams

In industry, polyurethane foams are obtained in two ways:

1. one-stage;
2. two-stage.

One-step method for the production of polyurethane foams

In a one-stage method, all components - diisocyanate, polyester, water, catalyst, stabilizer, emulsifier - are placed in a mixer at the same time and mixed in a reaction apparatus with a stirrer. Foaming occurs immediately, the rise of foam begins in about 10 seconds and ends in 1-2 minutes. The final curing of the foam lasts from several hours to several days.

Two-stage (prepolymer) method for producing polyurethane foams

In a two-stage (prepolymer) method for the production of polyurethane foams, the diisocyanate is first reacted with an oligoester (polyester), and the resulting prepolymer is then converted into polyurethane foam by mixing with water or an amine. The production of polyurethane foam products is carried out according to a continuous or periodic scheme (by pouring into paper forms), as well as by spraying.

Elastic polyurethane foams

Elastic polyurethane foams produced on the basis of complex and simple polyesters. Their most common representative is foam rubber... The raw material for its production is polyester based on adipic acid, diethylene glycol and small quantities trimethylolpropane, mix toluylene-2,4- and toluene-2,6-diisocyanates (65: 36 ) as well as water.

Technological process obtaining foam rubber in a block way (Fig. 1) consists of the stages of preparing raw materials, foaming polyurethane, manufacturing, aging and processing of foam blocks.

Preparation of raw materials consists in the preparation of an activator mixture. The mixture is prepared in mixers 3 in which from intermediate tanks 1 across measurer 2 feed catalyst (dimethylaniline), emulsifier (sodium salts of sulfonic acids), pore regulating additive (paraffin oil), and water.

Cooked activator mixture, complex polyester and mix toluene diisocyanatescontinuously injected into mixing head of the UBT-65 machine (4 ). The resulting mixture is fed through a drain pipe in a thin stream onto a continuously moving paper form, in which foam is formed.

Foaming takes place without heat supply and ends in about 1 minute. The form with foam is transported by transport through a tunnel with strong ventilation, where gases are released from the foam intensively. When exiting the tunnel, the shape falls on roller conveyor 5 from which it enters drying chamber 6 and then in car 7 for cutting blocks. Blocks stack stacker 8 on shelves 9 and transmitted to chamber 10 aging. In this case, the reactions between the components of the foam end, the foam cures and acquires the required strength. Aging lasts about 12-24 hours with continuous blowing of the blocks with air at room temperature.Finished blocks are processed for cutting machines 11 in sheets and packed.

Some properties of polyurethane foams depending on the composition of the composition (I-IV) are given below:

Composition of the composition, in mass parts	I	II	III	IV
Polyester	100	100	100	100
Toluene diisocyanate	45	39	39	31
Water	6,0	5,0	2,5	1,8
Catalyst	1,0	1,0	0,5	0,5
Emulsifier	4,2	2,0	1,0	1,0

The main physical and mechanical indicators of elastic polyurethane foams of the above compositions:

Physical and mechanical properties of flexible polyurethane foams	I	II	III	IV
Apparent density, kg / m 3	25	34	50	59
Breaking stress, MPa in tension	0,34	0,17	0,20	0,21
Breaking stress, MPa in compression (with a bend of 25%)	0,0055	0,0062	0,011	0,013
Elongation at break, %	398	450	400	350

Elastic polyurethane foams have high heat- and soundproof performance, good dielectric and shock absorption properties. They are capable of adhering to wood, metals, paper, fabrics, etc. Elastic polyurethane foams based on polyester have a higher strength when stretched, tenacity to oxidative aging, exposure to oils and solvents, but less elasticity and frost resistance and less resistance to aging in wet conditions than flexible polyurethane foams.

Properties flexible polyurethane foams domestic brands *

Index	PPU-E	PPU-ET	PPU-EM-1
Apparent density, kg / m 3	25 – 60	30 – 40	30 -50
Tensile strength, Mn / m 2 (kgf cm)	0,12 (1,2)	0,1 (1,0)	0,11-0,13 (1,1 -1,3)
Relative extension, %	150	100	150 – 170
Rebound elasticity, %	15	15	20 – 40
Relative permanent deformation at 50% compression for 72 hours at 20 ° C, %	10	15	10
Compressive stress at 40% deformation (kgf / cm 2)	0,0025 – 0,0075 (0,025 – 0,075)	0,003 – 0,01 (0,03 – 0,1)	0,004 – 0,01 (0,04 – 0,1)
Application temperature, ° С	from -15 to 100	from -20 to 100	from -50 to 100
Weight loss on combustion (fire tube method)	—	22	—
Sound absorption coefficient at 250 Hz	0,35	0,36	—
at 1000 hz	0,80	0,85	—
at 4000 Hz	0,75	0,80	—

*

Elastic closed cell foams are used for the manufacture of float products, mechanical supports, thermal insulation for operation at low (liquid nitrogen) and relatively high (up to 120 ° C) temperatures. Open cell foam is used to make sponges, cushions, seats, soundproofing materials, and more.

More and more applications are found integral polyurethane foamshaving a dense surface film and a foamed core, and the entire product is formed in one pouring cycle.

Rigid polyurethane foams

Rigid polyurethane foams are obtained mainly by pouring and spraying. According to the first method, the process is carried out “as follows.

At elevated temperature and stirring, a mixture of polyester with catalyst, emulsifier and water is prepared. After exposure at 30 ° C during 20-30 minutes add to the mixture toluene diisocyanate and mix the mass for 1-2 minutes.

In this case, the temperature of the mass increases by 5-10 ° C, it increases and partial foaming occurs. Then the mass is poured into restrictive molds corresponding to the configuration of the products. Foaming continues 30-35 minutes.

During this time, the form is filled with foam, which acquires the necessary and cellular structure. For obtaining polyurethane foams by spraying On the surface of various materials, a portable small-sized unit is used, which consists of heated containers for components, gear pumps and a spray gun with a stirrer. The thickness of the sprayed layer is 5-50 mm, apparent density - from 35 before 200 kg / m 3.

Physical and mechanical properties of some brands of rigid polyurethane foams based polyesters (products of interaction of diacids with polyhydric alcohols containing free hydroxyl and carboxyl groups) and diisocyanates (mixtures toluylene-2,4 and toluene-2,6-diisocyanates) are given below:

Apparent density, kg / m 3	60	100	200
Breaking stress in compression, MPa	0,20	0,78	2,45
Impact strength, kJ / m 2	0,48	0,39	0,59
Thermal conductivity coefficient, W / (m K)	0,024	0,031	0,057
Dielectric loss tangent at 10 10 Hz	1,05	1,1	1,23
Shrinkage (linear) in 24 hours,%	0,6	0,3	0,5
Upper limit of operating temperatures, ° С	100	130 – 150	170
Water absorption in 24 hours, kg / m 2	0,2	0,1	0,1

Rigid polyurethanes are characterized by good dimensional stabilityhave high heat- and soundproof performance... They are steady to the action of boiling water, gasoline, kerosene, lubricating oils, aqueous solutions of salts, ethyl alcohol, etc. Styrofoam easy to clean with soapy water; they resist mold and decay. Rigid polyurethane foams have good electrical insulation properties. In addition, they exhibit high (glass fiber, glass mats, etc.).

Properties of rigid polyurethane foams of domestic brands *

Index	PU-101	PU-101T	PPU-3S	PPU-304N
Apparent density,kg / m 3	100 – 200	150 – 250	50	30-50
Strength,Mn / m 2 (kgf / cm 2) not less in compression	1,0 – 1,9 (10 – 19)	2,0 – 4,2 (20 – 42)	0,25 (2,5)	0,15 – 0,5 (1,5 – 5)
bending	0,8 – 1,5 (8 – 15)	1,5 – 3,5 (15 – 35)	0,2 (2)	0,2 – 0,9 (2 – 9)
Impact strengthkJ / m 2 orkgf cm / cm 2 , not less	0,4	0,5 – 0,8	0,6	0,4 – 0,6
Coefficient of thermal conductivity, w / (m K)	0,031 – 0,035	0,033 – 0,047	0,033 – 0,038	0,023 – 0,035
Kcal / (m · h · ° С)	0,027 – 0,030	0,028 – 0,040	0,028 – 0,033	0,02 – 0,03
Water absorption in 24 hours, %, no more	0,3	0,3	0,3	0,3
Application temperature, ° C	from -50 to 150	from -60 to 200	from -60 to 60	from -60 to 100
Dielectric constant at 10 10 Hz	1,1 – 1,2	1,1 – 1,3	—	—
Dielectric loss tangent at 10 10 Hz	0,0015	0,0016 – 0,0020	—	—

* source - Encyclopedia of Polymers, ed. V.V. Kabanova 1974, volume 2, p. 567.

Polyurethane foams are used to fill gaps in concrete structures and cavities in the manufacture of doors and window frames, to finish caps, radars, tropical helmets, bearing planes and aircraft cabins, etc.

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