“Soluble Packaging” Has 3 Real-World Boundaries: Soluble Films / Laundry Bags / Water-Dispersible Paper-Based Structures — The First 3 Questions a Printer Should Ask When Receiving a “Dissolves on Contact with Water” Order

In April 2026, a client producing laundry products contacted us.

The client showed us a mesh bag and said: “We want to make something like this—a laundry bag. The customer buys it, puts dirty clothes into it, and throws it into the washing machine. After the wash, the bag dissolves on its own.”

We examined the mesh—a nylon mesh structure with heat-sealed edges.

Then we asked the client one question: “When you say ‘soluble,’ do you mean the entire mesh bag dissolves, or only the thread dissolves while the bag remains?”

The client replied: “Ah? Isn’t the whole thing supposed to dissolve?”

That is the problem. Fundamentally, a laundry bag is not “soluble packaging” but “a soluble seam with a non-soluble bag body.”The bag body is nylon (polyamide), which does not dissolve in a washing machine. What dissolves is the thread sealing the bag—typically water-soluble PVA thread or low-temperature water-soluble PVA thread.

If you quote and make promises based on the client’s understanding that the “entire bag dissolves,” problems are inevitable at delivery.

Therefore, today we will clarify the 3 categories of “soluble packaging.” They are entirely different in terms of materials, wastewater destinations, cost structures, and printability.

The First Boundary: Soluble Films—They Really “Dissolve,” but the Polymer Dissolves, Not the Waste

The first category is true soluble packaging: the entire package dissolves in water or water at a specified temperature.A typical example is the soluble film used for laundry detergent pods, which encases detergent in a water-soluble film.

The core material of these products is PVA (polyvinyl alcohol). It has several demanding characteristics:

• Strong hygroscopicity. PVA readily absorbs moisture, making humidity control in the packaging environment a prerequisite for production.
• Narrow heat-sealing window. PVA has a low melting point and a narrow heat-sealing temperature window, leaving very little room for adjustment in bag-forming process parameters.
• Extreme sensitivity to moisture. It absorbs moisture, becomes soft, and sticks to itself, so storage conditions for printers are far more demanding than those for ordinary paperboard boxes.
• Printability is a major challenge. PVA is hydrophilic. Water-based inks can achieve reasonable ink coverage, but adhesion is inconsistent; solvent-based inks compromise its solubility; and UV inks significantly affect dissolution speed after curing.

In 2019, our factory printed one order of detergent pod films and tested 3 approaches:

The table shows that: Printing soluble films is essentially a balancing exercise between “printing well” and “dissolving quickly,” and these two goals often work against each other.Therefore, when clients ask, “Can you print it?”, we never simply answer “Yes.” Instead, we ask 3 questions.

The Second Boundary: Laundry Bags—It Is the Thread That Dissolves, Not the Bag

Returning to the client mentioned at the beginning.

Clients generally understand laundry bags as products that “dissolve after use.” The actual structure is:

Bag body = non-soluble nylon mesh (polyamide); seal = PVA water-soluble thread or low-temperature water-soluble thread that dissolves on contact with water.

This difference has 3 practical consequences:

First, the wastewater destinations are completely different.The bag body does not dissolve and enters the washing machine’s drainage system as plastic waste—it passes through the filter and ultimately enters the domestic sewage system. Therefore, the genuine environmental benefit of a “soluble laundry bag” is that it eliminates the need to collect dirty clothes, hand-wash them, or carry them to the washing machine. It does not mean “no plastic waste is produced.”There is a risk if clients use this claim in marketing.

Second, the choice of soluble thread is constrained by washing conditions.Ordinary PVA thread generally dissolves above 60℃, which is called high-temperature water-soluble thread. If the client’s washing machine uses cold water at 30℃ or lower, low-temperature water-soluble thread is required. This is significantly more expensive, and the client must also be reminded that the bag will not dissolve in cold water.

Third, only the bag body can be printed, not the dissolvable thread.Moreover, the bag body is woven nylon—its mesh structure prevents detailed graphic printing.Only one or two colors can be used, generally printed in a corner of the bag for brand identification or a barcode. In other words, the printable space of laundry bags is extremely limited, and expectations of “printing an exquisite logo” often differ greatly from reality.

Our recommendation to the client is: Do not pursue visual impact on the bag body. Instead, add a printed label strip at the bag opening that does not come into contact with water—this is where brand information can be carried effectively.

The Third Boundary: Water-Dispersible Paper-Based Structures—Not “Dissolving,” but “Dispersing”

The third category is most easily confused with the first 2: water-dispersible paper-based structures.Typical examples include tea bags, paper versions of some laundry bags, and certain packages designed to be thrown into water and stirred until they disperse.

Its principle is entirely different: the polymer does not dissolve; instead, the paper’s fiber structure is broken down by water.A common method is to bond paper pieces with a specific water-soluble adhesive, or to use a specific process that loosens the paper fibers in water.

These structures have 3 real boundaries:

Boundary 1: They disperse slowly and unevenly.A tissue placed in water breaks apart within a few minutes, but a bonded paper structure takes longer to disperse and often begins at the edges while remaining hard in the center. Thus, “disperses on contact with water” may be valid in advertising, but in actual use it often means “soaked for half an hour and only partially dispersed.”

Boundary 2: They can be detrimental to recyclability.After water-soluble adhesives and special processes are introduced, this paper-based structure becomes difficult to identify and process within recycling systems. It can neither be recycled like ordinary paper nor necessarily be composted like plastic.It is stranded between the two systems. Therefore, “paper-based plus disperses on contact with water” does not necessarily mean environmentally friendly.

Boundary 3: When used in direct contact with food, the adhesive must comply with food-contact regulations.If this structure is intended to hold food—tea bags are the most typical example—the water-soluble adhesive must have corresponding food-contact compliance documentation (GB 4806 series / EU 10/2011 / FDA). The term “plant-based” cannot replace such documentation.

There is also a practical limitation for printers: Water-dispersible paper-based structures generally cannot be laminated or coated.Any barrier layer will negate the “disperses on contact with water” benefit. If clients require both water and oil resistance and dispersion on contact with water, the two requirements are physically contradictory. Our approach is to state this upfront rather than wait until the sample is completed and require rework.

When a Printer Receives a “Dissolves on Contact with Water” Order, Which 3 Numbers Should Be Asked First?

To summarize the 3 categories, when clients say, “We want soluble packaging,” our first question is always “Which category exactly is it?”This is because the pricing logic, testing requirements, and wastewater destinations are completely different.

The first number: Dissolution trigger conditions—what temperature and how long.This determines the material solution: PVA thread for temperatures above 60℃ and low-temperature thread that dissolves at 30℃ differ significantly in price. It also determines whether UV ink can be used, because the UV-cured layer significantly extends dissolution time.

The second number: Where do the dissolution products go—into the sewer, into composting, or into a specific recycling system?This determines whether the material has been selected correctly. Products that dissolve completely, such as soluble films, enter the sewer; the bodies of laundry bags are non-soluble nylon and pass through the filter; water-dispersible paper structures are stranded between recycling and composting systems. The term “soluble” does not automatically mean “eco-friendly.” It describes an action, not a destination.

The third number: How long will the package be used before disposal, and what will it come into contact with?This determines strength requirements and food-contact compliance levels. For food-contact applications, adhesives, inks, and solvent residues must all meet food-contact requirements. For dirty laundry, the standards are considerably lower and the budget is entirely different.

Only after these 3 numbers are clarified can we provide a quote that will not cause problems at delivery.Otherwise, the most common result is that clients expect the “entire bag to disappear,” receive a product with the bag body still intact, and then return it.

One Sentence for Clients

The term “soluble” is used too broadly in the packaging industry. It covers at least 3 things made from entirely different materials: polymer films that truly dissolve, laundry bags whose sealing thread dissolves, and paper-based structures that disperse through fiber breakdown.

Their costs can differ severalfold, their compliance pathways differ, and their environmental stories differ. Only the first category actually “disappears after use”; the other 2 either leave a bag body behind or become stranded within recycling systems.

Our recommendation is: Clearly explain the differences among these 3 categories on the quotation and clarify all 3 numbers.This is not about adding complexity. It is because clients will inevitably raise these differences after receiving samples. If we have already explained them, the result is a professional discussion. If not, the result is a complaint.

Further Reading

• 3 Certification Standards for Biodegradable Packaging Materials—Compostable / Biodegradable / Recyclable—“Soluble” and “compostable” are not the same; this article explains the boundaries among the 3 standards
• 3 Real-World Determinations for Biodegradation Testing—ISO 14855 Soil Burial / OECD 301 Aerobic / 18-Day Composting—Dissolution speed and biodegradability are two different things
• 4 Real-World Boundaries of Plant-Fiber Packaging Cushioning Materials—Wheat Straw / Rice Straw / Corn Starch / Cotton Fiber—A close relative of water-dispersible paper structures; this article covers compression-strength blind spots
• The Real Economics of 3 Types of Packaging Void Fill—Volumetric Weight / Loading Rate / Pallet Layers—The logistics economics for small products such as laundry bags and laundry detergent pods
• 3 Real-World Boundaries of Honeycomb Paperboard—Not a Cheap Alternative to EPE—Also a “paper-based alternative to plastic,” but its implementation path is entirely different